CN101614987A - Developing cartridge - Google Patents

Abstract

A developing cartridge comprising: a housing of a first side wall and a second side wall opposite to the first side wall; a developing roller disposed between the first side wall and the second side wall, the developing roller comprising a developing roller shaft rotating during development and a developing roller member configured to carry developer thereon, the developing roller member being disposed about said developing roller shaft, the developing roller shaft rotating about a first axis (X1) during developing; An electrode adjacent to the developing roller shaft on the first side wall, the electrode is electrically connected to the developing roller member; and a driven coupling portion provided on the second side wall, the driven coupling portion is connected to a drive of the image forming apparatus On the coupling portion and configured to rotate around the second axis (X2) during development, the electrode has a contact portion configured to contact a feeding member of the image forming apparatus; when the coupling portion is driven in a direction parallel to the axis of the developing roller When projected upward, at least a part of the contact portion is provided in the projected portion.

Description

Developing cartridge

This application is a divisional application of the following application,

Filing date of original application: May 31, 2006,

The application number of the original application: 200610092476.8,

The title of the invention of the original application: developing box.

Cross References to Related Applications

[0001] This application claims priority to the following Japanese patent applications: Patent Application 2005-200510 filed on July 8, 2005, patent application 2005-259644 filed on September 7, 2005, filed on December 27, 2005 2005-376522, the entire contents of which are incorporated herein by reference.

technical field

[0002] Aspects of the present invention relate to a developing cartridge for an image forming apparatus such as a laser printer.

Background technique

[0003] Generally, a developing cartridge containing toner is removably installed in a main body of an image forming apparatus such as a laser printer. The developing cartridge is also equipped in its housing with a toner chamber configured to store toner, an agitator rotatably disposed in the toner chamber, a supply roller configured to supply toner, a roller configured to carry toner thereon A developing roller configured as a layer thickness regulating blade that forms a thin layer of toner on the developing roller.

[0004] When the developing cartridge is driven after being installed in the main body, the toner in the toner chamber is supplied to the supply roller by the rotation of the agitator. Thereafter, the toner is supplied onto the developing roller according to the rotation of the supply roller. The toner then passes between the layer thickness regulating blade and the developing roller according to the rotation of the developing roller, thereby being carried on the developing roller as a thick layer. A developing bias is applied to the developing roller. Finally, the toner carried on the developing roller develops the electrostatic latent image formed on the photosensitive drum.

[0005] The developing cartridge includes a gear mechanism configured to drive a developing roller, a supply roller, and an agitator. For example, Japanese Patent Laid-Open Publication No. 2003-295614 discloses a gear mechanism provided on one side wall of the developing cartridge casing. The gear mechanism in the developing cartridge includes an input gear to which driving force is input from the main body of the image forming apparatus.

[0006] A bearing member configured to support the end of the developing roller is provided on the other side wall of the developing cartridge housing. The bearing member is integrally formed with a feed-in member that applies a developing bias to the developing roller.

[0007] In the developer cartridge disclosed in Japanese Patent Laid-Open Publication 2003-295614, a straight line parallel to the axis of the developing roller and passing through the input gear provided on one side wall, and another line parallel to the axis of the developing roller and passing through the The straight lines of the feed-in members on the other side wall are arranged parallel to each other with a certain distance therebetween. When a driving force is input from the main body of the image forming apparatus to the input gear, if such a rotational force or torsional force is applied to the developing cartridge that the developing cartridge rotates or twists around the input gear, the feed-in member provided on the other side wall is Inappropriate position, resulting in insufficient power supply or power feed from the main housing of the image forming apparatus.

Contents of the invention

[0008] Various aspects of the present invention provide a developing cartridge capable of stably moving toward a developing cartridge even when a driving force is directly transmitted from a driving coupling portion of an image forming apparatus to a driven coupling portion of the developing cartridge. The rollers feed or provide power.

In order to achieve above-mentioned various aspects, according to claim 1 of the present invention, developing cartridge comprises a housing, and this housing comprises first side wall and the second side wall opposite with first side wall; a development roller between the sidewall and the second sidewall, the development roller comprising a development roller shaft configured to rotate during development and a development roller member configured to carry developer thereon, the development roller member being disposed about the development roller shaft, a developing roller shaft rotates about a first axis during developing; an electrode disposed on the first side wall adjacent to the developing roller shaft, the electrode being electrically connected to the developing roller member; and a driven coupling portion disposed on the second side wall, The driven coupling is connected to the driving coupling of the image forming apparatus and is configured to rotate about the second axis during development. In an aspect described in claim 2, according to claim 1, the first axis and the second axis may be arranged parallel to each other. At least a portion of the electrode may be arranged to intersect the second axis.

[0010] When the driving force is directly transmitted from the driving coupling portion of the image forming apparatus to the driven coupling portion, and a rotational force or torque is applied to the developing cartridge to cause the developing cartridge to rotate or twist around the driven coupling portion, due to With the above structure, it is possible to prevent rotational force or torsion force from having a significant influence on the electrode, because at least a part of the electrode is arranged to intersect the second axis. In this way, the electrodes can be prevented from being in an improper position. Electric power can thereby be stably supplied to the developing roller.

[0011] According to claim 16 of the present invention, the developing cartridge may comprise a casing, the casing comprising a first side wall and a second side wall opposite thereto; a developing roller arranged between the first side wall and the second side wall, and developing The roller includes a development roller shaft configured to rotate during development and a development roller member configured to carry developer thereon, the development roller member disposed about the development roller shaft, the development roller shaft to rotate about a first axis during development; disposed at An electrode adjacent to the shaft of the developing roller on the first side wall, the electrode being electrically connected to the developing roller member; and a driven coupling portion provided on the second side wall, the driven coupling portion being connected to a drive of the image forming apparatus on the coupling and configured to rotate about the second axis during development. In one aspect, the first line extends perpendicular to the first axis and intersects the second axis, and the second line extends perpendicular to the first axis and intersects at least a portion of the electrode and the second axis. In another aspect of claim 17 according to claim 16, the first distance between the intersection of the first line and the first axis and the intersection of the first line and the second axis may be equal to the The second distance between the intersection point and the intersection point of the second line and the second axis.

[0012] When the driving force is transmitted from the driving coupling portion of the image forming apparatus to the driven coupling portion, and a rotational force or torsion force that causes the developing cartridge to rotate or twist around the driven coupling portion is applied to the developing cartridge, due to the above Because the first distance and the second distance are equal, it is possible to prevent the rotation force or torsion force from having a great influence on the electrodes. In this way, the electrodes can be prevented from being in an improper position. Electric power can thereby be stably supplied to the developing roller.

[0013] According to claim 32 of the present invention, the developing cartridge may comprise a casing comprising a first side wall and a second side wall opposite thereto; the developing device disposed between the first side wall and the second side wall a development roller comprising a development roller shaft configured to rotate during development and a development roller member configured to carry developer thereon, the development roller member disposed about the development roller shaft; disposed on the first side wall adjacent to An electrode of the developing roller shaft electrically connected to the developing roller member; and a driven coupling provided on the second side wall connected to the driving coupling of the image forming apparatus. When the driven coupling portion protrudes in a direction parallel to the developing roller axis, at least a part of the electrode may be disposed within the protruding portion.

[0014] When the driving force is directly transmitted from the driving coupling portion of the image forming apparatus to the driven coupling portion, and a rotational force or torsion force that causes the developing cartridge to rotate or twist around the driven coupling portion is applied to the developing cartridge, due to the above Since at least a part of the electrode is disposed within the projected portion when the driven coupling portion projects in a direction parallel to the developing roller axis, it is possible to prevent rotational force or torsional force from exerting a significant influence on the electrode. In this way, the electrodes can be prevented from being in an improper position. Electric power can thereby be stably supplied to the developing roller.

[0015] According to claim 46, in the developing cartridge according to any one of claims 1, 16 and 32, at least one end of the developing roller may be supported by at least one of the first side wall and the second side wall.

[0016] Due to this structure, at least one end of the developing roller may be supported by at least one of the first side wall and the second side wall. Therefore, when the developing roller is firmly supported, power can be stably supplied to the developing roller member.

[0017] According to claim 47, in the developing cartridge according to any one of claims 1, 16 and 24, each end of the developing roller may be supported by the first side wall and the second side wall.

[0018] Due to this structure, each end of the developing roller can be supported by the first side wall and the second side wall. Therefore, when the developing roller is firmly supported, electric power can be stably supplied to the developing roller member.

[0019] According to claim 48, in the developing cartridge according to any one of claims 1, 16 and 47, at least one end of the developing roller may be formed adjacent to at least one of the first side wall and the second side wall The set of member supports.

[0020] Due to this structure, at least one end of the developing roller can be supported by a member disposed adjacent to at least one of the first side wall and the second side wall. Therefore, the developing roller can be efficiently fitted or fastened to the adjacent member. When the developing roller is firmly supported, electric power can be stably supplied to the developing roller member.

[0021] According to claim 49, in the developing cartridge according to claim 48, each end of the developing roller may be supported by a first member disposed adjacent to the first side wall and a second member disposed adjacent to the second side wall.

[0022] Due to this structure, each end of the developing roller can be supported by a first member disposed adjacent to the first side wall and a second member disposed adjacent to the second side wall. Therefore, the developing roller can be efficiently fitted or fastened to the adjacent member. When the developing roller is firmly supported, electric power can be stably supplied to the developing roller member.

[0023] According to claim 50, in the developing cartridge according to any one of claims 1, 16, 32 and 46-49, the electrode may be made of metal.

[0024] Due to this structure, the electrodes can be made of metal. Electric power can therefore be reliably supplied to the electrodes.

[0025] According to claim 51, in the developing cartridge according to any one of claims 1, 16, 32 and 46-49, the electrode may be made of a conductive resin.

[0026] Due to this structure, the electrodes can be made of conductive resin. Therefore, the electrodes can be formed in any shape, and electric power can be stably supplied to the developing roller member.

[0027] According to claim 52, in the developing cartridge according to any one of claims 1, 16, 32, and 46-51, the developing roller shaft may include a conductive member. The electrodes and the developing roller member may be electrically connected through the developing roller shaft.

[0028] Due to this structure, the electrodes and the developing roller member can be electrically connected through the developing roller shaft. Electric power can therefore be reliably supplied from the electrodes to the developing roller member.

[0029] According to claim 53, in the developing cartridge according to claim 52, the developing roller shaft may be formed of a conductive material.

[0030] Due to this structure, the developing roller shaft can be formed of a conductive material. Electric power can therefore be more reliably supplied from the electrodes to the developing roller member.

[0031] According to claim 54, in the developing cartridge according to claim 53, the developing roller shaft may be formed of metal.

[0032] Due to this structure, the developing roller shaft can be made of metal. Therefore, electric power can be more reliably supplied from the electrodes to the developing roller member.

[0033] According to claim 55, in the developing cartridge according to any one of claims 52 to 54, the electrode may be a part of a member directly contacting the developing roller shaft.

[0034] Due to this structure, the electrode can be a part of the member directly contacting the developing roller shaft. Electric power can therefore be reliably supplied from the electrodes to the developing roller member.

[0035] According to claim 56, in the developing cartridge according to any one of claims 52 to 54, the electrode may indirectly contact the developing roller shaft through at least one conductive member.

[0036] Due to this structure, the electrode can indirectly contact the developing roller shaft through at least one conductive member. Therefore, the relative positions of the electrodes and the developing roller shaft can be freely selected. Thus, while the design is effectively improved, electric power can be reliably supplied from the electrodes to the developing roller member.

[0037] According to claims 3, 19 and 33, in the developing cartridges according to claims 1, 16 and 32, respectively, the electrode may surround a peripheral portion of the developing roller shaft.

[0038] Due to this structure, the developing roller may not be supported by other members. This reduces the number and cost of components that need to be used.

[0039] According to claim 57, in the developing cartridge according to claims 1, 16, 32 and 47-56, the driven coupling portion may include a first cylindrical portion and a second cylindrical portion disposed around the first cylindrical portion .

[0040] Due to this structure, the driven coupling portion may include a first cylindrical portion and a second cylindrical portion disposed around the first cylindrical portion. Therefore, the first cylindrical portion can reliably receive the driving force from the driving coupling. The second cylindrical portion can reliably transmit the driving force to the developing roller.

[0041] According to claim 58, in the developing cartridge according to claim 57, the first cylindrical portion is substantially hollow and provided with an inner peripheral surface from which the driven portion engaged with the drive coupling protrudes.

[0042] Due to this structure, by engaging the driven member with the drive coupling, the driving force can be reliably received from the drive coupling.

[0043] According to claim 59, in the developing cartridge according to claim 57 or 58, the first cylindrical portion may include a gear.

[0044] Due to this configuration, the first cylindrical portion may include a gear. The drive force can thus be reliably received from the drive coupling.

[0045] According to claims 4, 20 and 34, in the developing cartridges according to claims 1, 16 and 32, respectively, the developing roller may include a developing roller gear connected to be rotatable together with the developing roller shaft. The driven coupling may include a driving gear that directly engages with the developing roller gear.

[0046] Due to this structure, the driven coupling portion may include a driving gear that directly meshes with the developing roller gear. Therefore, the driving force received from the driving coupling through the driven coupling can be directly transmitted from the driven coupling to the developing roller gear. Thus, the developing roller can be reliably rotated. In addition, due to such a structure, the driving force from the image forming apparatus may not be directly transmitted to the developing roller gear, so that the developing roller shaft can serve as a guide during installation of the developing cartridge. Therefore, it is not necessary to separately provide guides, and the number and cost of parts used can be reduced.

[0047] According to claims 5, 21 and 35, the developing cartridges according to claims 4, 20 and 35, respectively, may further include a supply roller configured to supply the developer to the developing roller, the supply roller being disposed parallel to the developing roller. The supply roller may include a supply roller shaft configured to rotate during development, a supply roller member configured to supply developer to the developing roller, the supply roller member being disposed around the supply roller shaft, and a shaft connected to rotate with the supply roller shaft. A supply roller gear configured to mesh with the drive gear.

[0048] Due to this structure, the supply roller gear can be meshed with the drive gear. The driving force received by the driven coupling from the driving coupling can thus be transmitted from the driven coupling to the supply roller gear. In this way, the supply roller gear can be reliably rotated. Furthermore, due to this structure, the driving force can be transmitted from the driven coupling to the developing roller gear and the supply roller gear. Thus, the driving force can be effectively transmitted, and the developing roller and the supply roller can be efficiently rotated.

[0049] According to claims 6, 22 and 36, in the developing cartridges according to claims 5, 21 and 35, respectively, the electrode is electrically connectable to the supply roller.

[0050] Due to this structure, the electrodes can be electrically connected to the supply roller. Electric power can therefore also be supplied to the supply roller.

[0051] According to claims 7, 23 and 37, in the developing cartridges according to claims 6, 22 and 36, respectively, the electrode may have a first portion configured to surround a circumferential portion of the developing roller shaft and a first portion configured to surround the supply roller shaft. The second part of the circumference segment.

[0052] Due to this structure, the developing roller shaft and the supply roller shaft can be reliably supported by the first portion and the second portion, respectively.

[0053] According to claims 8, 24 and 38, in the developing cartridges according to claims 7, 23 and 37, respectively, the electrode may have a contact portion configured to contact a feeding member of the image forming apparatus, the contact portion being provided at the second One part and above the second part.

[0054] Due to this structure, the electrode may have a contact portion disposed over the first portion and the second portion. Therefore, the electrode can be brought into reliable contact with the feed-in member at the contact portion. In this way, electric power can be reliably supplied from the image forming apparatus to the electrodes.

[0055] According to claim 60, in the developing cartridge according to claims 1, 16 and 32, the developing cartridge may be installed in a photosensitive cartridge including a photosensitive member on which the electrostatic latent image is formed.

[0056] Due to this structure, the developing cartridge can be detachably installed in the photosensitive cartridge including the photosensitive member. Therefore, only the developing cartridge can be replaced with a new developing cartridge according to the amount of remaining developer, without considering the life of the photosensitive member. The photosensitive cartridge can be replaced according to the life of the photosensitive member without considering the amount of developer remaining in the developing cartridge.

[0057] According to claim 61, the developing cartridge according to claims 1, 16 and 32 may further include a protruding portion which contacts a biasing portion in the photosensitive cartridge when the developing cartridge is installed in the photosensitive cartridge.

[0058] Due to this structure, when the developing cartridge is installed in the photosensitive cartridge, the protruding portion of the developing cartridge can contact the biasing portion of the photosensitive cartridge, so that the developing roller can contact the photosensitive member. The developer carried on the developing roller can thus reliably develop the electrostatic latent image formed on the photosensitive member through reliable contact between the developing roller and the photosensitive member.

[0059] According to claim 62, in the developing cartridge according to claim 61, the protruding portion may extend outward from the first side wall and the second side wall.

[0060] Due to this structure, the protruding portion may extend outward from the first side wall and the second side wall. Therefore, the protruding portion can be reliably brought into contact with the biasing portion. This ensures reliable contact between the developing roller and the photosensitive member.

[0061] According to claim 39, in the developing cartridge according to claim 32, the driven coupling portion may include a first cylindrical portion and a second cylindrical portion disposed around the first cylindrical portion. The protrusion may be formed by protruding the first cylindrical portion. At least a portion of the electrode is disposed within the protrusion.

[0062] Due to this structure, the electrodes can also be prevented from being placed in an inappropriate position. This ensures stable power supply to the developing roller.

[0063] According to claim 63, in the developing cartridge according to claim 39, the first cylindrical portion may be substantially hollow and provided with an inner peripheral surface from which the driven member engaged with the drive coupling protrudes .

[0064] Due to this structure, by engaging the driven member with the drive coupling portion, it is possible to reliably receive the driving force from the drive coupling portion.

[0065] According to claims 9, 25 and 40, in the developing cartridge according to claims 1, 16 and 32, the electrode may include a first portion configured to surround a circumferential portion of the developing roller shaft. The first portion may be movably arranged to contact the developing roller shaft.

[0066] Due to this structure, electric power can be reliably supplied to the developing roller.

[0067] According to claims 10, 26 and 41, in the developing cartridges according to claims 9, 25 and 40, respectively, the electrode may include a second portion attached to the first side wall by a fixing member. The fixing member sidewall includes a portion configured to prevent separation of the electrode from the first sidewall. One end surface of the second portion faces and is spaced apart from one end surface of the portion of the fixing member.

[0068] Due to this structure, the first portion can reliably contact the developing roller.

[0069] According to claims 11, 27 and 42, in the developing cartridges according to claims 10, 26 and 41, respectively, the fixing member may be a screw, and the portion of the fixing member may be a screw head.

[0070] Due to this structure, the electrode can be reliably and easily attached to the first side wall by the screw, so that the electrode moves slightly.

[0071] According to claims 12, 28 and 43, in the developing cartridges according to claims 10, 26 and 40, respectively, the first side wall may be provided with a receiving portion configured such that the second portion surrounds the receiving portion And the fixing member is inserted into the receiving portion. The end surface of the receiving portion may be configured to protrude outward from the end surface of the second portion to contact the end surface of the portion of the fixing member.

[0072] Due to this structure, the fixing member may be provided with a certain distance between the fixing member and the second part. Therefore, the distance between the end surface of the second portion and the end surface of the fixing member can be set precisely and reliably. Therefore, the first portion can reliably contact the developing roller shaft while ensuring smooth rotation of the developing roller shaft relative to the first portion.

[0073] According to claims 13 and 29, in the developing cartridges according to claims 10 and 26, respectively, the first portion and the contact portion may extend from the first side wall along the first axis in a direction relative to the second side wall .

[0074] Due to this structure, the feeding member of the image forming apparatus can be reliably brought into contact with the contact portion. When the smooth rotation of the developing roller shaft relative to the developing roller shaft supporting part is ensured, the developing roller shaft supporting part can reliably contact the developing roller shaft.

[0075] According to claims 15, 31 and 45, the developing cartridges according to claims 1, 16 and 32, respectively, may further include a supply roller configured to supply the developer to the developing roller. The supply roller may be disposed parallel to the developing roller. The supply roller may include a supply roller shaft configured to rotate during development and a supply roller member configured to supply developer to the developing roller. A supply roller member may be provided around the supply roller shaft. The electrode may be provided with a portion configured to surround a circumferential portion of the supply roller shaft.

[0076] Due to this structure, electric power can also be supplied to the supply roller.

[0077] According to claim 64, in the developing cartridge according to any one of claims 10-13, 15, 26-29, 31, 41-43 and 45, the bearing configured to support the developing roller shaft can be separated from the electrode set on the first side wall.

[0078] Due to this structure, the developing roller shaft can be supported by the bearing. Therefore, the developing roller shaft supporting portion can reliably contact the developing roller shaft. At the same time, the smooth rotation of the developing roller shaft is ensured. Electric power can be reliably supplied to the developing roller even when the bearing is not used as the electrode.

[0079] According to claims 14, 30 and 44, in the developing cartridges according to claims 8, 26 and 40, respectively, the electrode may include a second portion attached to the first side wall by a screw. The first side wall may be provided with a screw receptacle configured such that the second portion surrounds the screw receptacle and the screw is screwed into the screw receptacle. The distance between the center of the screw receiving portion and the shaft axis of the developing roller is different from the distance between the center of the area surrounded by the second portion and the center of the area surrounded by the first portion, and the screw receiving portion is configured to be surrounded by the second portion. In the second part, the peripheral portion of the developing roller shaft is enclosed in the first part.

[0080] Due to this structure, the side wall, the first portion can reliably contact the developing roller.

[0081] According to claim 1, it is possible to prevent the electrode from being in an inappropriate position. Thus, electric power can be stably supplied to the developing roller.

[0082] According to claim 16, it is possible to prevent the electrode from being in an inappropriate position. Thus, electric power can be stably supplied to the developing roller.

[0083] According to claim 32, it is possible to prevent the electrode from being in an inappropriate position. Thus, electric power can be stably supplied to the developing roller.

[0084] According to claim 46, when the developing roller is firmly supported, electric power can be stably supplied to the developing roller member.

[0085] According to claim 47, when the developing roller is firmly supported, electric power can be stably supplied to the developing roller member.

[0086] According to claim 48, the developing roller can be efficiently fitted or fixed to the adjacent member. When the developing roller is firmly supported, electric power can be stably supplied to the developing roller member.

[0087] According to claim 49, the developing roller can be efficiently fitted or fixed to the adjacent member. When the developing roller is firmly supported, electric power can be stably supplied to the developing roller member.

[0088] According to claim 50, electric power can be stably supplied to the electrodes.

[0089] According to claim 51, the electrodes can be formed in any shape, and electric power can be stably supplied to the developing roller member.

[0090] According to claim 52, electric power can be stably supplied from the electrode to the developing roller member.

[0091] According to claim 53, electric power can be more stably supplied from the electrode to the developing roller member.

[0092] According to claim 54, electric power can be more reliably supplied from the electrode to the developing roller member.

[0093] According to claim 55, electric power can be stably supplied from the electrode to the developing roller.

[0094] According to claim 56, the relative positions of the electrode and the developing roller shaft can be freely selected. Thus, when the design is effectively improved, electric power can be reliably supplied from the electrodes to the developing roller member.

[0095] According to claims 3, 19 and 33, the developing roller may not be supported by other members. In this way, the number of parts used and the cost can be reduced.

[0096] According to claim 57, the first cylindrical portion can reliably receive the driving force from the drive coupling portion. The second cylindrical portion can reliably transmit the driving force to the developing roller shaft.

[0097] According to claim 58, the driving force can be reliably received from the driving coupling portion.

[0098] According to claim 59, the driving force can be reliably received from the driving coupling portion.

[0099] According to claims 4, 20 and 34, the developing roller can be reliably rotated, and furthermore, the developing roller shaft can play a guiding role during installation of the developing cartridge. In this way, both the number of parts used and the cost can be reduced.

[00100] According to claims 5, 21 and 35, the supply roller can be reliably rotated. In addition, the developing roller and the supply roller can rotate efficiently.

[00101] According to claims 6, 22 and 36, electric power may also be supplied to the supply roller.

[00102] According to claims 7, 23, 37, the developing roller shaft and the supply roller shaft can be reliably supported by the first portion and the second member, respectively.

[00103] According to claims 8, 24 and 38, electric power can be reliably supplied from the image forming apparatus to the electrodes.

[00104] According to claim 60, only the developing cartridge can be replaced with a new developing cartridge in accordance with the amount of remaining developer without considering the life of the photosensitive member. The photosensitive cartridge can be replaced according to the life of the photosensitive member without regard to the amount of residual developer contained in the developing cartridge.

[00105] According to claim 61, with reliable contact between the developing roller and the photosensitive member, the electrostatic latent image formed on the photosensitive member can be reliably developed by the developer carried on the developing roller.

[00106] According to claim 62, reliable contact between the developing roller and the photosensitive member can be ensured.

[00107] According to claim 39, it is further possible to prevent the electrode from being in an inappropriate position. Thus, electric power can be stably supplied to the developing roller.

[00108] According to claim 63, the driving force can be reliably received from the driving coupling portion.

[00109] According to claims 9, 25 and 40, electric power can be reliably supplied from the feeding member to the developing roller shaft through the contact portion and the first portion.

[00110] According to claims 10, 26 and 41, the first portion can be reliably brought into contact with the developing roller.

[00111] According to claims 11, 27 and 42, the electrode can be reliably and easily attached to the first side wall by means of a screw.

[00112] According to claims 12, 28 and 43, the first portion can be reliably brought into contact with the developing roller shaft while ensuring smooth rotation of the developing roller shaft relative to the first portion.

[00113] According to claims 13 and 29, the feeding member of the image forming apparatus can be reliably brought into contact with the contact portion. While ensuring the stable rotation of the developing roller shaft relative to the first part, the first part can be in reliable contact with the developing roller shaft.

[00114] According to claims 15, 31 and 45, electric power may also be supplied to the supply roller.

[00115] According to claim 64, while ensuring smooth rotation of the developing roller shaft, the first portion ( can reliably contact the developing roller shaft. Even when the bearing is not used as an electrode, electric power can be reliably supplied to the developing roller shaft.

[00116] According to claims 14, 30 and 44, the first portion can be reliably brought into contact with the developing roller.

Brief description of the drawings

[00117] Various illustrative aspects will now be described in detail with reference to the following drawings, in which:

[00118] FIG. 1 is a side sectional view of an overall structure of a laser printer as an image forming apparatus according to an illustrative aspect;

[00119] FIG. 2 is a side cross-sectional view of a process cartridge used in the laser printer shown in FIG. 1, according to an illustrative aspect;

[00120] FIG. 3 is a side cross-sectional view of a drum cartridge for use in the laser printer shown in FIG. 1, according to an illustrative aspect;

[00121] FIG. 4 is a side cross-sectional view of a developer cartridge for use in the laser printer shown in FIG. 1, according to an illustrative aspect;

[00122] FIG. 5 is a perspective view of the developing cartridge viewed from the upper rear left side;

[00123] FIG. 6 is a perspective view of the developing cartridge viewed from the upper rear right side;

[00124] FIG. 7 is a perspective view of the developing cartridge viewed from the lower front left side;

[00125] FIG. 8 is a perspective view of the developing cartridge viewed from the lower front right side;

[00126] FIG. 9 is a plan view of the developing cartridge viewed from the rear side;

[00127] Fig. 10 is a plan view of the developing cartridge viewed from the front side;

[00128] FIG. 11 is a plan view of the developing cartridge viewed from the top;

[00129] Fig. 12 is a plan view of the developing cartridge viewed from the bottom;

[00130] FIG. 13 is a left side view of the developing cartridge with the gear cover attached to the developing cartridge;

[00131] FIG. 14 is a left side view of the developing cartridge with the gear cover removed from the developing cartridge;

[00132] Fig. 15 is a right side view of the developing cartridge;

[00133] FIG. 16 is a perspective view of the drum cartridge as seen from the top rear left side;

[00134] FIG. 17 is a perspective view of the process cartridge seen from the upper front right side;

[00135] FIGS. 18A and 18B provide a perspective view and a side view of a development shaft, respectively, showing a portion of a development shaft according to an illustrative aspect;

[00136] FIG. 19 is a left side view of the developing cartridge corresponding to FIG. 13 according to an illustrative aspect, the contact plate protruding in the width direction of the developing cartridge;

[00137] FIG. 20 is a right side view of the developing cartridge corresponding to FIG. 15 according to an illustrative aspect, the driven coupling portion protruding in the width direction of the developing cartridge;

[00138] FIG. 21 is a perspective view from the upper rear right side of the developing cartridge corresponding to FIG. 6, with the electrode member removed from the developing cartridge, according to an illustrative aspect;

[00139] FIG. 22 is a perspective view from the lower front right side of the developing cartridge corresponding to FIG. 8, with the electrode member removed from the developing cartridge, according to an illustrative aspect;

[00140] FIG. 23 is a right side view of the developing cartridge corresponding to FIG. 15;

[00141] Fig. 24 is a sectional view of the developing cartridge along line A-A of Fig. 23;

[00142] Fig. 25 is a sectional view of the developing cartridge taken along line B-B of Fig. 23 .

Detailed ways

[00143] Note that various relationships among the respective components will be set forth in the following description. Note that these relationships may generally be direct or indirect unless otherwise specified, and it is not the intent of this description to limit this relationship in this respect.

[00144] Various illustrative aspects are explained below with reference to the drawings. 1 is a side sectional view of an overall structure of a laser printer in which a developing cartridge is installed according to an illustrative aspect. 2 is a side sectional view of a process cartridge used in the laser printer shown in FIG. 1 according to an illustrative aspect, and FIG. 3 is a side sectional view of a process cartridge used in the laser printer shown in FIG. 1 according to an illustrative aspect. Side sectional view of a drum cartridge, FIG. 4 is a side sectional view of a developing cartridge used in the laser printer shown in FIG. 1, according to an illustrative aspect.

[00145] As shown in FIG. 1, a laser printer 1 includes a main casing 2, a feeding unit 4 that supplies paper 3, and an image forming unit 5 that forms an image on the supplied paper 3. Both the feeding unit 4 and the image forming unit 5 are provided in the main casing 2 .

[00146] (1) main housing

An opening 6 is formed on the front side (right side in FIG. 1 ) of the main casing 2 through which the process cartridge 20 is inserted into or removed from the main casing 2 . A front cover 7 for opening and closing the opening 6 is provided on the front side of the main casing 2 . The front cover 7 is pivotally supported by a cover shaft 8 inserted into a lower end portion of the front cover 7 . The opening 6 is closed by the front cover 7 when the front cover 7 is pivotally closed about the cover shaft 8 . When the front cover 7 is pivotally opened around the cover shaft 8, the opening 6 is opened. Thus, the process cartridge 20 can be inserted into or removed from the main casing 2 through the opening 6 .

[00147] In the following description, when the process cartridge 20 is installed in the main casing 2, the side where the front cover 7 is provided is defined as the front side of the laser printer 1/process cartridge 20 (including the developing cartridge 30), opposite The side on the front side is defined as the rear side.

[00148] (2) feed-in unit

As shown in Fig. 1, the feed-in unit 4 is arranged at the bottom in the main casing 2, the paper supply tray 9 is slidably installed in the main casing 2 along the front-rear direction, and the separation roller 10 and the separation pad 11 are arranged on the paper Providing the upper front end portion of the tray 9, the pickup roller 12 is provided on the rear side of the separation roller 10 (upstream side of the separation pad 11 in the sheet feeding direction). The feeding unit 4 also includes a paper dust removal roller 13 provided on the upper front portion of the separation roller 10 (downstream side of the separation roller 10 in the paper feeding direction) and a pinch roller 14 provided facing the paper dust removal roller 13 .

[00149] The feeding unit 4 includes a pair of registration rollers 15 positioned below the process cartridge 20 when installed downstream of the paper feeding path in a U-shaped portion bent in the vicinity of the paper powder removal roller 13 toward U-shape on the back side. A paper mounting plate 16 configured to stack paper 3 thereon is provided in the paper supply tray 9 . The paper installation plate 16 is substantially parallel to the bottom plate of the paper supply tray 9, and its front end is positioned at a lower installation position at the same time, and the paper installation plate 16 is an angle, and its front end is at a higher position at the same time. Pivot.

[00150] At the front end of the paper supply tray 9, a lever 17 for lifting the front end of the paper mounting plate 16 is provided. The lever 17 is supported under the front end portion of the paper mounting plate 16 so as to pivot about a lever shaft 18 provided at the rear end of the lever 17 . The lever 17 is pivotable between a parallel position in which the front end of the lever 7 is substantially parallel to the bottom plate of the paper supply tray 9 and an angular position in which the front end of the lever 17 is at the lifting paper mounting plate 16 . When a driving force is input to the lever shaft 18 , the lever 17 pivots about the lever shaft 18 . Accordingly, the front end of the lever 17 lifts the front end of the paper mounting plate 16 to move the paper mounting plate to the supply position.

[00151] When the paper mounting plate 16 is in the supply position, the uppermost paper 3 on the paper mounting plate 16 is pressed against the pickup roller 12, and is fed between the separation roller 10 and the separation pad 11 by the rotation of the pickup roller 12 the separation position.

[00152] When the paper supply tray 9 is removed from the main housing 2, the paper mounting plate 16 is placed in the mounting position. When the paper mounting plate 16 is placed in the mounting position, a stack of papers can be mounted on the paper mounting plate 16 .

[00153] The sheets 3 fed toward the separation position by the pickup roller 12 are separated one by one by the rotation of the separation roller 10 while being sandwiched between the separation roller 10 and the separation pad 11. The fed paper 3 passes through a portion between the paper dust removal roller 13 and the pinch roller 14 from which paper dust or fibers are removed. Then, the paper 13 is fed toward the registration roller 15 along the U-shaped paper feeding path.

[00154] The registration roller 15 registers the paper 3 or reduces the skew of the paper 3. The registration roller 15 then feeds the sheet 3 to a transfer position between the photoconductive drum 28 as a photosensitive member and the transfer roller 31, where the toner image on the photoconductive drum 28 is transferred to the sheet 3 on.

[00155] Image forming unit

The image forming unit 5 includes a scanning unit 19 , a process cartridge 20 and a fixing unit 21 .

[00156] (a) scanning unit

The scanning unit is arranged on the upper part of the main casing 2. The scanning unit 19 includes a laser source (not shown), a polygon mirror 22 driven to rotate, an fθ lens 23 , a reflection mirror 24 , a lens 25 and a reflection mirror 26 . As indicated by the dotted line shown in FIG. 1 , the laser beam emitted from the laser source based on the image data is deflected by the polygon mirror 22 and passes through the fθ lens 23 . The laser beam is then reflected by the mirror 22 and passes through the lens 25 to the mirror 26 where it is bent downward toward the surface of the photoconductive drum 28 of the process cartridge 20 . The surface of the photoconductive drum 28 is thus irradiated with the laser beam.

[00157] (b) process cartridge

The process cartridge 20 is detachably mounted in the main casing 2 below the scanning unit 19 through the opening 6 . As shown in FIG. 2, the process cartridge 20 includes a drum cartridge 27 as a photosensitive cartridge and a developing cartridge 30 detachably housed in the drum cartridge according to at least one illustrative aspect of the present invention.

[00158] (b-1) drum case

As shown in FIG. 3 , the drum cartridge 27 includes a drum frame 58 , a photoconductive drum 28 , a scorotron charger 29 , a transfer roller 31 and a cleaning member 32 provided in the drum frame 58 .

[00159] The drum frame 58 includes an upper frame 141 supporting the charger 29 and the cleaning member 32, and a lower frame 142 supporting the photoconductive drum 28 and the transfer roller 31.

[00160] As shown in FIGS. 3 and 16, the lower frame 142 is provided with a bottom wall 143 integrally formed so as to open upward, left and right side walls 144L, 144R, a front wall 15 and a rear wall 146. The bottom wall 143 is substantially in the shape of a rectangular plate. The left and right side walls 144L, 144R are arranged to face each other at the left and right ends of the bottom wall 143 . The front wall 145 is disposed at the front end of the bottom wall 143 . The rear wall 146 is provided at the rear end of the bottom wall 143 .

[00161] A front portion of the lower frame 142 is defined as a developing cartridge installation portion 147 in which the developing cartridge 30 is installed. The rear portion of the lower frame 142 is defined as a drum support portion 148 in which the lower frame 142 and the upper frame 141 face each other in the vertical direction while the photoconductive drum 28 is supported there.

[00162] As shown in FIG. 3, the photosensitive drum 28 includes a cylindrical drum body 33 having a positively chargeable photoconductive layer made of, for example, polycarbonate on its outermost surface, and a metal drum shaft 34, The drum shaft 34 is disposed at the axis of the drum body 33 in the axial direction of the drum body 33 . The drum shaft 34 is supported by left and right side walls 144L, 144R of the lower frame 142 . The drum body 33 is rotatably supported on a drum shaft 34 . During image formation, the photoconductive drum 28 is driven to rotate on a drum shaft 34 by inputting a driving force from a motor (not shown).

[00163] The scorotron charger 29 is supported by the upper frame 141 at the upper rear portion of the photoconductive drum 28. The scorotron charger 29 is arranged to face the photoconductive drum 28 with a certain distance therebetween so as to prevent the scorotron charger 29 from contacting the photoconductive drum 28 . The charger 29 includes a discharge wire 67 facing the photoconductive drum 28 and having a certain distance therefrom, and a grid that is arranged between the discharge wire 67 and the photoconductive drum 28 for controlling the charging amount from the discharge wire 67 to the photoconductive drum 28 68. During image formation, a bias voltage is applied to the gate electrode 68 . Simultaneously, a high voltage is applied to the discharge wire 67 to generate corona discharge from the discharge wire 67 . Thus, the surface of the photoconductive drum 28 is uniformly charged positively by the charger 29 .

[00164] The transfer roller 31 is disposed below the photoconductive drum 28 in the lower frame 142. The transfer roller 31 contacts the photoconductive drum 28 in the vertical direction to form a nip portion between the transfer roller 31 and the photoconductive drum 28 . The transfer roller 31 includes a metal transfer roller shaft 56 covered with a rubber roller body 57 made of a conductive rubber material. The transfer roller shaft 56 is rotatably supported by left and right side walls 144L, 144R of the lower frame 142 . In the process of transferring toner to the paper 3 (image forming process), driving force is input from a motor (not shown) to rotate the transfer roller 31 . A transfer bias is applied to the transfer roller 31 during transfer of the toner to the paper 3 .

[00165] The cleaning member 32 is supported by the upper frame 141 behind the photosensitive drum 28 so as to face the drum 28. The cleaning member 32 includes a cleaning brush 65 for capturing paper powder or fibers on the photoconductive drum 28 , and a support plate 66 that supports the cleaning brush 65 facing the photoconductive drum 28 relative to the cleaning brush 65 (behind the photoconductive drum 28 ).

[00166] The cleaning brush 65 includes a nonwoven fabric having a plurality of conductive fibrous bristles secured thereto. The cleaning brush 65 is attached to the support plate 66 by double-sided tape. The cleaning brush 65 is provided to contact the photoconductive drum 28 . The support plate 66 is supported by the upper frame 141 while supporting the cleaning brush 65 .

[00167] A direction parallel to the drum axis 34 of the photoconductive drum 28 may be referred to as a "first direction." A direction directed to the front side of the main housing 2 perpendicular to the first direction may be referred to as a "second direction". In the developing cartridge installation portion 147 , a handle 149 to be held during installation or removal of the drum cartridge 27 is formed at a substantially central portion of the front wall 145 in the first direction.

[00168] A pressure lever 150 is provided at each end of the front wall 145 with respect to the first direction, which presses the developing cartridge 30 installed in the developing cartridge mounting portion 147 toward the rear side, thereby firmly pressing the developing roller 38 against the on the photoconductive drum 28. Each pressure lever 150 is made of a thick plate and is triangular in side view. The lower end of each pressure lever 150 is pivotally supported by a fixed shaft (not shown) extending inwardly from the left and right side walls.

[00169] A compression spring (not shown) is disposed between each pressure lever 150 and the front wall 145. Therefore, each pressure lever 150 is always pressed backward or tilted backward by the urging force of the compression spring.

[00170] The lock lever 151 is provided on one side wall (the right side wall 144R) and there is a distance between the lock lever 151 and a pressure lever 150 in the front-rear direction. The lock lever 151 has a substantially rectangular shape when viewed from the side. The lock lever 151 is equipped with a flexible portion 152 extending downward from the lock lever 151 . The lock lever 151 is pivotally supported by the right side wall 144R through a flexible portion 152 that engages with a rib (not shown) formed on the bottom wall 143 .

[00171] A guide groove 153 along which the ring member 116 and the developing roller shaft cover 118 (described later) is guided to guide the developing cartridge in the rear developing cartridge mounting portion 147 of the left and right side walls 144L, 144R 30 is installed in the developing cartridge mounting portion 147. As shown in FIGS. 2 and 3, a mounting base 155 on which the mounting portion 133 of the developing cartridge 30 is placed is formed in the developing cartridge mounting portion 147 slightly forward of the central portion of the bottom wall 143 in the second direction.

[00172] (b-2) developer cartridge

As shown in FIGS. 16 and 17 , the developing cartridge 30 is detachably installed in the developing cartridge mounting portion 147 of the lower frame 142 when the process cartridge 20 is separated from or removed from the main casing 2 . As shown in FIG. 4 , the developing cartridge 30 includes a developing frame 36 and a supply roller 37 provided in the developing frame 36 , a developing roller 38 and a layer thickness regulating blade 39 .

[00173] The developing frame 36 is formed in a box shape opened rearward. A partition plate 40 and a toner chamber 41 and a development chamber 42 partitioned by the partition plate 40 are provided in the developing frame 36 . The partition plate 40 is disposed in the middle of the developing frame 36 in the second direction, partitioning the developing frame 36 in the front-rear direction. The opening 43 is formed in the middle of the partition plate 40 in the vertical direction.

[00174] The toner chamber 41 is defined in the inner space of the developing frame 36 on the front side partitioned by the partition plate 40. The toner chamber 41 contains a positively chargeable non-magnetic one-component toner as a developer. The toner is, for example, a polymerized toner obtained by copolymerizing a polymerizable monomer using a polymerization method such as a suspension polymerization method. The polymerizable monomer may be a styrene based monomer such as styrene, or an acrylic based monomer such as acrylic acid, alkacrylic acid, alkyl methacrylic acid. The particles of this polymerized toner have a substantially spherical shape, so that the polymerized toner has excellent fluidity to facilitate high-quality image formation.

[00175] The toner is mixed with paraffin and a colorant such as carbon black and an external additive such as silica for improving the fluidity of the toner. The average particle size of the toner is about 6-10μm.

[00176] Toner filling ports through which toner is supplied into the toner chamber 41 are formed on left and right side walls 69L, 69R (described later) of the developing frame 36 in the toner chamber 41. As shown in FIG. 15, the toner filling opening is covered with a toner cap 35. As shown in FIG.

[00177] Toner detection windows 44 for detecting the amount of remaining toner are provided on the respective left and right side walls 69L, 69R of the developing frame 36 in the toner chamber 41. Toner detection windows 44 are formed near the partition plate 40 on the left and right side walls 69L, 69R of the developing frame 36, facing each other along the width direction of the developing cartridge 30 (perpendicular to the front-rear direction and the vertical direction). As shown in FIGS. 13 , 14 and 15 , the respective toner detection windows 44 are formed by fitting transparent circular plates into openings formed in the left and right side walls 69L, 69R of the developing frame 36 .

[00178] In the toner chamber 41, an agitator 45 for agitating the toner in the toner chamber 41 is provided. The stirrer 45 is equipped with a stirrer shaft 46 and a stirring member 47 . The agitator shaft 46 is rotatably supported at the substantially central portion of the toner chamber 41 by the left and right side walls 69L69R of the developing frame 36 . The stirring member 47 is provided on the stirrer shaft 46 . A driving force of a motor (not shown) is input to the agitator shaft 46 to rotate the agitator 45 during development (image formation).

[00179] The stirrer 45 is equipped with a wiper 48. Each wiper 48 is disposed on each end of the stirrer rotating shaft 46 relative to the axial direction thereof. As the agitator shaft 46 rotates, each wiper 48 pivotally moves around the agitator shaft 46 in the circumferential direction in the toner chamber 41 to clean the toner set on the left and right side walls 69L, 69R of the developing frame 36. Detection window 44 . Thus, the toner detection window 44 is cleaned by the wiper 48 .

[00180] The developing chamber 42 is defined in the inner space of the developing frame 36 at the rear side partitioned by the partition plate 40. The supply roller 37 is disposed behind the upper opening 43 of the middle bottom wall 75 (details will be described later). The supply roller 37 includes a metal supply roller shaft 50 covered by a sponge roller body 51 composed of a conductive foam material as a supply roller member. The supply roller shaft 50 is rotatably supported by the left and right side walls 69L, 69R of the developing frame 36 in the developing chamber 42 . Each end of the supply roller shaft 50 extends outward from the left and right side walls 69L, 69R. Driving force of a motor (not shown) is input to the supply roller shaft 50 to rotate the supply roller 37 during development (image formation). During development (image formation), the same developing bias as that applied to the developing roller 38 is applied to the supply roller 37 .

[00181] As shown in FIG. 4, the developing roller 38 is disposed behind the supply roller 37 in the developing chamber 42, and above the rear bottom wall 76 (described below). The developing roller 38 contacts the supply roller 37 so as to exert a certain pressure on each other. The developing roller 38 includes a metal developing roller shaft 52 covered with a rubber roller body 53 made of a conductive rubber material as a developing roller member. The developing roller shaft 52 extends parallel to the supply roller shaft 50 . The developing roller shaft 52 is rotatably supported by left and right side walls 69L, 69R (described below) of the developing frame 36 in the developing chamber 42 .

[00182] Each end of the developing roller shaft 52 extends outward from left and right side walls 69L, 69R (described in detail below). The rubber roller body 53 is made of conductive polyurethane or silicone rubber containing fine carbon particles. The surface of the rubber roller body 53 is coated with fluorine-containing urethane rubber or silicone rubber. During development (image formation), a driving force of a motor (not shown) is input to the developing roller shaft 52 to rotate the developing roller 38 . A developing bias is applied to the developing roller 38 during development (image forming process).

[00183] The layer thickness regulating sheet 39 includes a blade body 54 made of a metal spring sheet and a pressure portion 55 made of insulating silicone rubber with a semicircular cross-section. A pressure portion 55 is provided at a free end of the blade body 54 . The base end of the blade body 54 of the layer thickness regulating blade 39 opposite to the free end is supported above the developing roller 38 in the blade attachment portion 77 (described below) by the attachment member 134 . The free end of the blade body 54 slopes downward and extends forward toward the supply roller 37 . The elastic force of the blade body 54 presses the pressure portion 55 against the developing roller 38 .

[00184] (b-3) developing and transferring operations

During image formation, the driving force of a motor (not shown) is input to the agitator shaft 46, and the agitator shaft 46 rotates, thereby causing the agitation member 47 to pivot in the circumferential direction inside the toner chamber 41 around the agitator shaft 46. . Accordingly, the toner in the toner chamber 41 is agitated by the agitating member 47 and discharged toward the developing chamber 42 through the opening 43 formed at the center of the partition plate 40 in the vertical direction for fluid communication in the front-rear direction.

[00185] The toner discharged toward the developing chamber 42 through the opening 43 is supplied to the rubber roller body 53 of the developing roller 38 through the sponge roller body 51 of the supply roller 37 according to the rotation of the supply roller shaft 50. At this time, the toner is positively charged by friction between the sponge roller body 51 of the supply roller 37 and the rubber roller body 53 of the developing roller 38 . The toner supplied onto the rubber roller body 53 of the developing roller 38 passes between the pressure portion 55 of the layer thickness regulating blade 39 and the rubber roller body 53 of the developing roller 38 according to the rotation of the developing roller shaft 52 . The toner as a thin layer whose thickness is adjusted is carried on the rubber roller body 53 of the developing roller 38 .

[00186] As shown in FIG. 2, when the photoconductive drum 28 rotates, the surface of the drum body 33 is uniformly charged positively by the grid-controlled corona charger 29. The laser beam from the scanning unit 19 then scans across the surface of the drum 33 at high speed, thereby forming an electrostatic latent image corresponding to the image to be formed on the paper 3 on the surface of the drum 33 .

[00187] Next, when the positively charged toner carried on the rubber roller body 53 of the developing roller 38 comes into contact with the drum body 33 of the photoconductive drum 28 as the developing roller shaft 52 rotates, the toner is supplied As for the electrostatic latent image formed on the surface of the drum body 33, that is, the portion exposed to the laser beam provided to the surface of the drum body 33 has a lower potential energy than the remaining portion which is uniformly positively charged. Thus, the electrostatic latent image on the drum body 33 can be seen. In this way, the electrostatic latent image on the drum body 33 becomes visible. Thus, a toner image is formed on the drum body 33 by reverse development.

[00188] Then, when the paper 3 conveyed by the registration roller 15 passes through the transfer position between the drum body 33 and the rubber roller body 57 of the transfer roller 15, by applying transfer to the rubber roller body 57 of the transfer roller 31, The printing bias voltage is used to transfer the toner image carried on the surface of the drum body 33 to the paper 3 . The paper 3 with the toner image transferred thereon is fed into the fixing unit 21 .

[00189] The toner remaining on the surface of the drum body 33 after the transfer of the toner image is collected by the rubber roller body 53 of the developing roller 38. Paper powder or fibers adhering to the surface of the drum body 33 due to contact with paper after the transfer of the toner image are removed from the surface of the drum body 33 of the photoconductive drum 28 by the cleaning brush 65 of the cleaning member 32 .

[00190] (c) fixing unit

As shown in FIG. 1, the fixing unit 21 is disposed behind the process cartridge 20, and there is a distance between the photoconductive drum 28 of the process cartridge 20 and the fixing unit 21 in a substantially horizontal direction. The fixing unit 21 includes a unit frame 59 , and a heating roller 60 and a pressure roller 61 provided in the unit frame 59 .

[00191] The heating roller 60 includes a metal tube coated with a fluorocarbon resin and a halogen lamp embedded in the metal tube for heat application. The heat roller 60 is rotated by input power from a motor (not shown) during fixing (during image formation).

[00192] The pressure roller 61 is disposed below the heating roller 60 to oppose the heating roller 60 so as to be pressed against the heating roller 60. The heat roller 61 includes a metal roller shaft covered with a rubber roller body made of a rubber material. The pressure roller 61 is driven by the rotation of the heating roller 60 .

[00193] In the fixing unit 21, when the paper 3 passes between the heating roller 60 and the pressure roller 61, the toner image transferred onto the paper 3 at the transfer position is thermally fixed. The paper 3 with the toner image fixed thereto is conveyed toward a paper output tray 62 formed on the top surface of the main casing 2 . A paper output path from the fixing unit 21 to the paper output tray 62 is formed in a substantially U-shape, turning from the fixing unit 21 to the front side. Feed rollers 63 are provided in the paper output path. An output roller 64 is provided at the downstream end of the paper output path.

[00194] The paper 3 subjected to heat-fixing processing at the fixing unit 21 is conveyed onto a paper output path. The paper 3 is fed to the output roller 64 by the feed roller 63 . The paper 3 is then output onto the paper output tray 62 by the output roller 64 .

2. developing cartridge

Fig. 5 is a perspective view of the developing cartridge seen from the upper rear left side; Fig. 6 is a perspective view of the developing cartridge viewed from the upper rear right side; Fig. 7 is a perspective view of the developing cartridge viewed from the lower front left side; Fig. 8 is a perspective view of the developing cartridge viewed from the lower front right side; Fig. 9 is a plan view of the developing cartridge viewed from the rear side; Fig. 10 is a plan view of the developing cartridge viewed from the front side; Fig. 11 is a plan view of the developing cartridge viewed from the top ; FIG. 12 is a plan view of the developing cartridge viewed from the bottom; FIG. 13 is a left side view of the developing cartridge with the gear cover attached to the developing cartridge; FIG. 14 is a left side of the developing cartridge without the gear cover attached to the developing cartridge Views; FIG. 15 is a right side view of the developing cartridge; FIG. 19 is a left side view of the developing cartridge corresponding to FIG. 13 in which the contact plate protrudes in the width direction of the developing cartridge; FIG. 20 is a driven coupling portion corresponding to FIG. 15 A right side view of the developing cartridge protruding in the width direction of the developing cartridge;

[00196] Next, the developing cartridge 30 will be described in detail with reference to FIGS. 4-15, 19 and 29. FIG.

[00197] (1) developing frame

As shown in FIGS. 4 and 5 , the developing frame 36 includes a pair of left and right side walls 69L, 69R, an upper wall 70 , a bottom wall 71 and a front wall 72 integrally formed. The developing frame 36 is formed in a box shape, and the rear opening 73 is formed on the upper surface.

[00198] The left and right side walls 69L, 69R are both flat. As shown in FIG. 11 , the left and right side walls 69L, 69R are disposed to face each other in the first direction to dispose the toner chamber 41 and the developing chamber 42 between the left and right side walls 69L, 69R. 14, 15, the left and right side walls 69L, 69R are adjacent to each end of the toner chamber 41 and the developing chamber 42. As shown in FIG. As shown in Figures 4 and 11, the upper wall 70 is flat. The upper wall 70 is connected to the upper ends of the left and right side walls 69L, 69R so as to extend between the left and right side walls 69L, 69R. The upper wall 70 closes the upper portions of the toner chamber 41 and the developing chamber 42 .

[00199] As shown in FIGS. 4 and 7, the bottom wall 71 has a curved plate shape. The bottom wall 71 is connected to the lower ends of the left and right side walls 69L, 69R so as to extend between the left and right side walls 69L, 69R. The bottom wall 71 closes the lower portions of the toner chamber 41 and the developing chamber 42 . The bottom wall 71 includes an integrally formed front bottom wall 74 , a middle bottom wall 75 and a rear bottom wall 76 .

[00200] The front bottom wall 74 is formed in a substantially semicircular cross-sectional shape in relation to the rotation path of the agitator 45 in the toner chamber 41.

[00201] The middle bottom wall 75 is disposed behind the front bottom wall 74. The middle bottom wall 75 is formed in a substantially semicircular cross-sectional shape in relation to the supply roller 37 in the developing cartridge 42 .

[00202] The rear bottom wall 76 is disposed behind the middle bottom wall 75. The rear bottom wall 76 slopes downward from the front side to the rear side.

[00203] The front wall 72 is flat. The front wall 72 is connected to the front ends of the left and right side walls 69L, 69R so as to extend between the left and right side walls 69L, 69R. The front wall 72 closes the front of the toner chamber 41 .

[00204] As shown in FIG. 4, a blade attaching portion 77 is provided at upper rear portions of the left and right side walls 69L, 69R between the left and right side walls 69L, 69R. The blade attachment portion 77 is formed in a substantially triangular shape in side section so that the width of the blade attachment portion 77 is narrowed toward the lower side. The rear end surface of the blade attaching portion 77 is formed as an inclined surface inclined from the upper end to the lower end of the blade attaching portion 77 toward the front side.

[00205] As shown in FIGS. 4 and 9, the base end of the blade body 54 is fixed to the rear end surface of the blade attachment portion 77 by an attachment member 134, and a sealing member 135 is provided on the rear end surface of the blade attachment portion 77 and the blade Between the base ends of body 54. A sealing member 135 is provided on the rear end surface of the blade attachment portion 77 to prevent toner from leaking from a portion between the rear end surface of the blade attachment portion 77 and the attachment member 134 .

[00206] The attachment member 134 includes a front support member 138 shaped like a plate, a rear support member 136 having a substantially L-shaped cross-section, and a screw 137. The front support member 138 is disposed on the rear side of the sealing member 135 . The base end of the blade body 54 is disposed on the rear side of the front support member 138 . The rear support member 136 is provided on the rear side of the base end of the blade body 54 . The screw passes through the rear support member 136, the base end of the blade body 54 and the front support member 138 in the front-rear direction, thereby integrally fastening the rear support member 136, the base end of the blade body 54 and the front support member 138 together. The base end of the blade body 54 is fixed to the blade attachment portion 77 by the fixing screw 139, while the base end of the blade body 54 and the attachment member 134 clamp the sealing member 135 between the base end of the blade body 54 and the blade attachment portion 77 between.

[00207] (0109) As shown in FIGS. 4 and 5, the rear opening portion 73 is defined by the rear support member 136 of the attachment member 134, the rear ends of the left and right side walls 69L, 69R, and the rear end of the rear bottom wall 76. The rear opening portion 73 has a substantially rectangular shape extending in the first direction. A part of the developing roller 38 is exposed from the rear opening portion 73 . More specifically, as shown in FIG. 13 , a portion of the developing roller 38 protrudes outward from the inside of the developing frame 36 through the rear opening portion 73 as viewed from the side.

[00208] As shown in FIG. 9, the developing roller 38 is arranged such that each end portion of the developing roller shaft 52 is rotatably supported in opposing side walls 69L, 69R. A ring member 116 is mounted on one end of the developing roller shaft 52 extending from the left side wall 69L. As shown in FIGS. 5 and 7 , the end portion of the developing roller shaft 52 is inserted into a developing roller shaft inserting portion 111 of a gear cover 93 (detailed below) provided on the left side wall 69L side together with a ring member 116 . An end portion of the developing roller shaft 52 is rotatably supported in the developing roller shaft insertion portion 111 of the gear cover 93 .

[00209] As shown in FIGS. 6 and 8 and described below, a bearing member 201 provided on one side of the right side wall 69R is mounted on the other end of the developing roller shaft 52 extending from the right side wall 69R. The other end of the developing roller shaft 52 extends through the bearing member 201 . The electrode member 117 is provided on the bearing member 201 side. The developing roller shaft cover 118 formed in the electrode member 117 is mounted on the other end of the developing roller shaft 52 passing through the bearing member 201 . The developing roller shaft 52 is rotatably supported in the developing roller shaft cover portion 118 of the electrode member 117 . Thus, the end portion of the developing roller 38 is supported by the developing roller shaft insertion portion 111 of the gear cover 93 and the developing roller shaft covering portion 118 of the electrode member 117 .

[00210] When the developing cartridge 30 is mounted in the developing cartridge mounting portion 147, the ring member 116 and the developing roller shaft covering portion 118 are guided by the guide grooves 153 formed in the side walls 144L, 144R of the developing cartridge mounting portion 147, as Figure 17 shows. In this way, it is ensured that the developing cartridge 30 is smoothly installed in the developing cartridge installing portion 147 .

[00211] As shown in FIGS. 5 and 9, with respect to the width direction of the developing cartridge 30, rear side end walls 78 are provided below the rear opening portion 73 on the rear end of the rear bottom wall 76 at the left and right sides thereof. Each rear side end wall 78 is formed in a substantially L shape with an inner lower portion cut away. The reinforcing portion 80 is provided between the rear side end walls 78 on the rear end of the rear bottom wall 76 below the rear opening portion 73 .

[00212] The reinforcing portion 80 extends between the rear side end walls 78 along the width direction of the developing cartridge 30. The reinforcing wall 80 fits in the cut-out between the rear side end walls 78 . As shown in FIGS. 4 and 5 , the reinforcing portion 80 is continuously formed from the rear end of the rear bottom wall 76 . The reinforced portion 80 includes a reinforced upper wall 82 , a reinforced front wall 85 , a reinforced bottom wall 83 and a reinforced side wall 84 . These walls 82-85 are integrally formed in a substantially box-like shape open towards the rear. More specifically, the reinforcing portion 80 is formed in a substantially U-shape with the rear open as seen in a side sectional view perpendicular to the width direction of the developing cartridge 30 .

[00213] The upper reinforcing wall 82 is integrally formed with the rear end of the rear bottom wall 76 to extend rearwardly. The reinforced front wall 85 is integrally formed with the rear end of the rear bottom wall 76 to extend downward from the front end of the reinforced upper wall 82 . The reinforced bottom wall 83 is arranged to face the reinforced upper wall 82 in the vertical direction. The reinforced bottom wall 83 is formed integrally with the lower end of the reinforced front wall 85 to extend rearward and downward.

[00214] The reinforced side wall 84 is integrally formed with the ends of the reinforced upper wall 82, the reinforced front wall 85 and the reinforced bottom wall 83 with respect to the width direction of the developing cartridge 30. As shown in FIG. 4 , the lower film 87 is attached to the reinforced upper wall 82 . The lower film 87 is formed of, for example, polyethylene terephthalate. The rear end portion of the lower film 87 is attached to the upper surface of the reinforcing upper wall 82 , and extends forward and upward to contact the lower surface of the rubber roller body 53 of the developing roller 38 . Accordingly, the lower film 87 closes the gap between the reinforced upper wall 82 and the developing roller 38 to prevent toner leakage from the gap.

[00215] As shown in FIGS. The guide plate 81 is formed in the shape of a rib or a flat plate extending in the front-rear direction and downward from the bottom wall 71 . Adjacent guide plates 81 are disposed parallel to each other in the width direction of the developing cartridge 30 and spaced apart from each other by a certain distance.

[00216] More specifically, the rear end of each guide plate 81 is connected to the reinforced front wall 85 and the reinforced bottom wall 83. The front end of each guide plate 81 is connected to the rear end portion of the front bottom wall 74 . Each guide plate 81 extends downward from the rear bottom wall 76 , the middle bottom wall 75 and the front bottom wall 74 . Each guide plate 81 is integrally formed with the reinforced bottom wall 83 , the reinforced front wall 85 , the rear bottom wall 76 , the middle bottom wall 75 and the front bottom wall 74 . The lower end of each guide plate 81 extends from the rear end of the reinforcing bottom wall 83 to the front side in a substantially linear manner, bends upward and forward under the middle bottom wall 75 , and finally reaches the rear end of the front bottom wall 74 .

[00217] As shown in FIGS. 7 and 12, a guide reinforcement plate 86 that reinforces each guide plate 81 is provided on the middle bottom wall 75. As shown in FIG. The guide reinforcing plate 86 has a plate shape extending downward from the middle bottom wall 75 in a direction substantially perpendicular to the front-rear direction at a certain middle portion of the guide plate 81 with respect to the front-rear direction thereof. The guide reinforcing plate 86 connects the guide plates 81 in the width direction of the developing cartridge 30 to reinforce each guide plate 81 .

[00218] The front bottom wall 74 is provided with a mounting portion 133 and a mounting plate 88 for mounting the developing cartridge 30 in the developing cartridge mounting portion 147 of the drum frame 58. Each mounting portion 133 is provided at a position of the front bottom wall 74 at each end thereof in the middle with respect to the front-rear direction with respect to the width direction of the developing cartridge 30 . Each mounting portion 133 is formed at the bottom of the front bottom wall 74 in the shape of a substantially rectangular plate in bottom view.

[00219] A pair of mounting plates 88 facing each other in the width direction of the developing cartridge 30 is formed on the front end of the front bottom wall 74 at each end with respect to the width direction of the developing cartridge 30. Each mounting plate 88 is formed in a substantially triangular shape extending downward from the front bottom wall 74 . The lower end of each mounting plate 88 extends in the front-rear direction slightly above each mounting portion 133 .

[00220] As shown in FIGS. 7 and 10, the front wall 72 of the development frame 36 is provided with a handle 89. The handle 89 is formed in a substantially U-shape in plan view. The handle includes two handle support plates 90 disposed on the front wall 72 with a certain distance therebetween in the width direction of the developing cartridge 30 and a handle 91 disposed between the handle support plates 90 . Each handle support plate 90 has a plate shape extending forward from the upper portion of the front wall 72 . A handle 91 is attached to the front end of the handle support plate 90 .

[00221] Protrusions 132 are provided on the respective left and right side walls 69L, 69R of the developing frame 36 as pressure receiving portions. When the developing cartridge 30 is installed in the developing cartridge mounting portion 147 of the drum frame 58 , the protrusion 132 contacts the associated pressure lever 150 . The respective protrusions 132 are provided at the front lower portions of the respective left and right side walls 69L, 69R, protruding outward from the outer surfaces of the side walls 69L, 69R. As shown in FIGS. 14 and 15 , each protrusion 132 is formed in a substantially U-shape opened rearward when viewed from the side. The respective protrusions 132 are provided at positions symmetrical with respect to the first direction on the left and right side walls 69L, 69R.

[00222] When the developing cartridge 30 is installed in the developing cartridge mounting portion 147 of the drum cartridge frame 58, the mounting portion 133 is placed on the relevant mounting base 155, as shown in FIG. 2, and the mounting plate 88 is placed on On the bottom wall 143 of the developing cartridge mounting portion 147 .

[00223] As shown in FIGS. 8, 16 and 17, the front end of each protrusion 132 contacts the associated pressure lever 150. Each protrusion 132 is pressed backward by the associated pressure lever 150 by the urging force of the compression spring pushing the pressure lever 150 . Accordingly, the developing frame 36 moves backward relative to the developing cartridge mounting portion 147 , so that the rubber roller body 53 of the developing roller 38 is pressed against the photoconductive drum 28 .

[00224] As shown in FIGS. 6 and 8, the engagement portion 181 is provided integrally with the right side wall 69R behind the protrusion 132 to extend outward. The engaging portion 181 is positioned under the lock lever 151 when the developing cartridge 30 is installed in the developing cartridge mounting portion 147 of the drum cartridge 27 . The lock lever 151 is engaged with the engaging portion 181 by the pushing force of the flexible portion 152 . When the developing cartridge 30 is removed from the developing cartridge mounting portion 147 , the lock lever 151 is pressed down to disengage the engagement portion 181 from the lock lever 151 .

(2) gear mechanism portion and gear cover

As shown in FIG. 14 , end portions of the agitator shaft 46 , the supply roller shaft 50 and the developing roller shaft 52 protrude outward in the first direction from the left side wall 69L as the second side wall. As shown in FIGS. 5 and 13 , provided on the left side wall 69L are a gear mechanism portion 92 for driving the rotation of the agitator shaft 46 , the supply roller shaft 50 and the developing roller shaft 52 , and a gear cover covering the gear mechanism portion 92 93.

[00226] As shown in FIG. 14, the gear mechanism portion 92 is provided on the left side wall 69L. The gear mechanism part 92 includes an input gear 94 as a driven coupling part, a supply roller driving gear 95 as a supply roller gear, a developing roller driving gear 115 as a developing roller gear, an intermediate gear 96, an agitator driving gear 97 and a detection gear. 98.

[00227] The input gear 94 is rotatably supported between the developing roller shaft 52 and the agitator shaft 46 by an input gear support shaft 99 extending outward from the left side wall 69L in the first direction.

[00228] The input gear 94 is integrally equipped with the driven coupling part 100 as the first cylindrical part, and the driving gear 101 as the second cylindrical part. The driving gear 101 is arranged concentrically with the driven coupling part 100 and surrounds the driven coupling part. Around 100 Union Department. The driven coupling part 100 is hollow cylindrical. An engagement stopper portion 102 as a driven portion that engages with a driving coupling portion 200 ( FIG. 5 ) as a driving coupling portion extends radially inward from an inner peripheral surface of the driven coupling portion 100 . The mesh stoppers 102 are disposed to face each other with respect to the input gear support shaft 99 . In this way, the driven coupling part 100 is formed as gear teeth meshing with the driving coupling part 200 (see FIG. 5 ).

[00229] The driving gear 101 is disposed adjacent to the driven coupling portion 100 in the first direction between the driven coupling portion 100 and the left side wall 69L.

[00230] A supply roller drive gear 95 is mounted on one end of the supply roller shaft 50 to mesh with the input gear 94 below it. The supply roller gear 95 is provided to rotate together with the supply roller shaft 50 so that the supply roller drive gear 95 does not rotate relative to the supply roller shaft 50 .

[00231] The developing roller drive gear 115 is mounted on one end of the developing roller shaft 52 to mesh with the input gear 94 on the lower rear side thereof. The developing roller driving gear 115 is arranged to rotate together with the developing roller shaft 52 so that the developing roller driving gear 115 does not rotate relative to the developing roller shaft 52 .

[00232] In front of the input gear 94, the intermediate gear 96 is rotatably supported on the intermediate gear support shaft 103 extending outward from the first side wall 69L in the first direction. The intermediate gear 96 is integrally provided with an external gear 104 meshing with the input gear 94 and an internal gear 105 meshing with the agitator drive gear 97 . The internal gear 105 is disposed inside the external gear 104 with respect to the width direction of the developing cartridge 30 .

[00233] The agitator drive gear 97 is mounted on one end of the agitator shaft 46 to rotate with the agitator shaft 46 so that the agitator drive gear 97 does not rotate relative to the agitator shaft 46. The agitator drive gear 97 is positioned on the lower front side of the intermediate gear 96 . The agitator drive gear 97 is integrally equipped with an internal gear 106 meshing with the internal gear 105 of the intermediate gear 96 and an external gear 107 meshing with the detection gear 98 . The external gear 107 is disposed outside the internal gear 106 in the width direction of the developing cartridge 30 .

[00234] The detection gear 98 is rotatably supported on the upper front side of the agitator drive gear 97 by the detection gear support shaft 108 extending outward from the left side wall 69L in the first direction. The detection gear 98 is a partially missing tooth gear. The detection gear 98 is integrally formed with a usage determination protrusion 109 extending radially outward of the detection gear support shaft 108 . The detection gear 98 is urged by a coil spring 110 wound around a detection support shaft 108 to mesh with the external gear 107 of the agitator drive gear 97 .

[00235] As shown in FIG. 13, a gear cover 93 is attached to the left side wall 69L of the developing cartridge 30, covering the gear mechanism portion 92 from the outside with respect to the width direction of the developing cartridge 30. The gear cover 93 has a developing roller shaft insertion hole 111 into which the developing roller shaft 52 and the ring member 116 are inserted, and also has an input hole 112 through which the driven coupling portion 100 is exposed. In addition, the gear cover 93 is provided with a detection gear cover portion 113 that covers the detection gear 98 on the front side of the input hole 112 .

[00236] The detection gear cover portion 113 extends outward in the first direction. The detection gear 98 is fitted in an extension of the detection gear cover 113 . A fan-shaped detection window 114 is formed on the rear side of the detection gear cover 113 . The use determination protrusion 109 that moves in the circumferential direction of the detection gear 98 according to the rotation of the detection gear 98 is exposed from the detection window 114 .

[00237] As shown in FIG. 5, when the process cartridge 20 with the developing cartridge 30 disposed therein is mounted in the main casing 2, the drive coupling 200 is inserted into the driven coupling of the input gear 94 of the developing cartridge 30. In the coupling part 100 , a driving force from a motor (not shown) provided in the main housing 2 is transmitted to the drive coupling part 200 . In this way, the driven coupling part 100 is engaged with the driving coupling part 200 .

[00238] The driving coupling part 200 is removably inserted into the driven coupling part 100 with respect to the opening/closing action of the front cover 7 of the main housing 2. More specifically, when the front cover 7 is opened, the driving coupling part 200 is withdrawn from the driven coupling part 100 so that the process cartridge 20 can be removed from the main casing 2 . When the process cartridge 20 with the developing cartridge 30 disposed therein is installed in the main casing 2 through the opening 6 and then the front cover 7 is closed, the driving coupling 200 is pushed forward and inserted into the driven coupling 100 .

[00239] When the driving force from the motor is input from the driving coupling portion 200 to the driven coupling portion 100, the input gear 94 rotates. Then, the supply roller drive gear 95 that directly meshes with the drive gear 101 of the input gear 94 rotates. Thus, the supply roller shaft 50 causes the supply roller 37 to rotate. Also, the developing roller driving gear 115 directly meshing with the driving gear 101 of the input gear 94 rotates. Thus, the developing roller shaft 52 causes the supply roller 37 to rotate.

[00240] Furthermore, the external gear 104 of the intermediate gear 96 meshing with the drive gear 101 of the input gear 94 is rotated. The internal gear 105 of the intermediate gear 96 integrally formed with the external gear 104 is rotated. When the internal gear 105 of the intermediate gear 96 rotates, the internal gear 106 of the agitator driving gear 97 meshing with the internal gear 105 of the intermediate gear 96 is rotated. Thus, the agitator shaft 46 causes the agitator 45 to rotate.

[00241] When the internal gear 106 of the agitator driving gear 97 is rotated, the external gear 107 of the agitator driving gear 97 integrally formed with the internal gear 106 is rotated. Next, the detection gear 98 meshing with the external gear 107 of the agitator drive gear 97 rotates.

[00242] When the developer cartridge 30 is not in use, the detection gear 98 is placed in a position as shown in FIG. engage. Once the detection gear 98 is rotated, the tooth-missing portion of the detection gear 98 faces the external gear 107 of the agitator driving gear 97 so that the detection gear 98 is not meshed with the external gear 107 . Therefore, the detection gear 98 will not rotate any more. In one direction, the use determining protrusion 109 of an unused developing cartridge 30 goes over the detection window 114 only once. In the laser printer 1 , determination as to whether to use or not to use the mounted developing cartridge 30 is made by detecting whether the use determination protrusion 109 moves using a use detection sensor (not shown) provided in the main casing 2 .

[00243] (3) electrode member

As shown in FIGS. 6, 8 and 15, a bearing member 201 supporting one end of the developing roller shaft 52 is provided on the right side wall 69R as the first side wall. The bearing member 201 is made of a non-conductive resin material in the shape of a flat plate. A ring portion 202 having an inner diameter substantially the same as that of the developing roller shaft 52 is integrally formed on the bearing member 201 at its rear end. The ring portion 202 has a cylindrical shape, and the developing roller shaft 52 is inserted thereinto. An end portion of the developing roller shaft 52 is slidably and rotatably supported on the inner peripheral surface of the ring portion 202 .

[00244] (0138) Two engagement openings 128 are formed on the rear side of the bearing member 201 so that the ring portion 202 is inserted between the engagement openings 128 in the vertical direction. An opening (not shown) for receiving the supply roller shaft 50 is formed on the front side of the bearing member 201 . Two engaging protrusions 129 are formed on the right side wall 69R at positions corresponding to the engaging openings 128 . The bearing member 201 is attached to the right side wall 69R such that the rear end of the bearing member 201 is flush with the rear end of the right side wall 69R. Since the bearing member 201 is attached to the right side wall 69R, the developing roller shaft 52 and the supply roller shaft 50 are respectively inserted into the ring portion 202 and openings (not shown), the engaging protrusions 129 are fitted in the associated engaging openings 128 .

[00245] An electrode member 117 as an electrode for applying a developing bias to the developing roller shaft 52 is formed on the surface of the bearing member 201. The electrode member 117 is made of a conductive resin including carbon powder. The electrode member 117 is integrally equipped with an attachment plate 120 , a developing roller shaft covering portion 118 as a developing roller shaft supporting portion, and a terminal portion 119 .

[00246] The attachment plate 120 is formed of a thin plate into a substantially triangular shape viewed from the side. The developing roller shaft cover 118 is provided on the rear end of the attachment plate 120 . The developing roller shaft cover portion 118 is formed in a cylindrical shape to receive one end of the developing roller shaft 52 and is disposed concentrically with the ring portion 202 . The developing roller shaft cover 118 extends from the rear end of the attachment plate 120 in the first direction.

[00247] The developing roller shaft 52 has a large diameter portion supported by the ring portion 202 and a small diameter portion supported by the developing roller shaft cover portion 118. The diameter of the large-diameter portion is larger than the diameter of the small-diameter portion. The outer diameter of the developing roller shaft covering portion 118 is substantially the same as the inner diameter of the ring portion 202 . A portion of the developer roller shaft shroud 118 fits within the ring portion 202 when the developer roller shaft shroud 118 is inserted onto the developer roller shaft 52 .

[00248] The terminal portion 119 is provided at the front end of the attachment plate 120 with a certain distance between the terminal portion 119 and the developing roller shaft cover portion 118 in the front-rear direction. The terminal portion 119 is provided with a base 121, a contact plate 122 as a contact portion.

[00249] The base 121 is integrally provided with a base plate 123 extending vertically to form an ellipse when viewed from the side, and an annular peripheral plate 124 extending outward from the periphery of the base plate 123 in the width direction of the developing cartridge 30. A portion of the outer edge plate 124 formed on the upper end of the base plate 123 extends outward in the first direction, and this portion is longer than the remaining portion of the outer edge plate 124 .

[00250] The contact plate 122 is substantially U-shaped with its opening facing downward when viewed from the side. The contact plate 122 extends outward in a first direction from an outer edge plate 124 formed at an upper end of the base 121 .

[00251] The attachment plate 120 is formed with an upper reinforcing rib 125, a lower reinforcing rib 126, and a supply roller shaft cover 127 as a supply roller supporting portion. The upper reinforcing rib 125 extends outward from the attachment plate 120 in a first direction. The upper reinforcing rib 125 is formed such that it extends backward and downward from the rear end of the contact plate 122 toward the developing roller shaft cover 118 and is connected to the developing roller shaft cover 118 .

[00252] The lower reinforcing rib 126 extends outward from the attachment plate 120 in a first direction to form a U-shape substantially opening upward when viewed from the side while covering the lower portion of the terminal portion 119. More specifically, the lower reinforcing rib 126 includes a first lower reinforcing rib 126A, a second lower reinforcing rib 126B, and a third lower reinforcing rib 126C formed continuously.

[00253] The first lower reinforcing rib 126A extends rearward and downward from its upper end. The upper end of the first lower reinforcing rib 126A is connected to the upper reinforcing rib 125 provided between the developing roller shaft cover portion 118 and the terminal portion 119 . The lower end of the first lower reinforcing rib 126A is connected to the third lower reinforcing rib 126C.

[00254] The upper end of the second lower reinforcing rib 126B is connected to the front lower end of the base 121. The upper end of the second lower reinforcing rib 126B extends backward and downward parallel to the first lower reinforcing rib 126A. The lower end of the second lower reinforcing rib 126B is connected to the third lower reinforcing rib 126C.

[00255] The third lower reinforcing rib 126C is disposed below the base 121 so as to connect the lower ends of the first lower reinforcing rib 126A and the second reinforcing rib 126B.

[00256] (0145) The supply roller shaft cover 127 is provided between the base 121 and the third lower reinforcing rib 126C. The supply roller shaft cover 127 is formed in a cylindrical shape to receive one end of the supply roller shaft 50 . The supply roller shaft cover 127 extends outward from the contact plate 120 shorter than the outer edge plate 124 in the first direction.

[00257] Screw holes (not shown) are formed on the base plate 123 of the base 121. Screw holes (not shown) are also formed on the bearing member 201 at positions corresponding to the screw holes on the base plate 123 . Screw holes (not shown) are formed on the right side wall 69R at positions corresponding to the screw holes on the base plate 123 .

[00258] While causing the ends of the developing roller shaft 52 and the supply roller shaft 50 to be inserted into the developing roller shaft cover 118 and the supply roller shaft cover 127, respectively, using the screw hole inserted on the base plate 123, the bearing The threaded member holes on member 201 are then threaded into the threaded members 130 of the threaded holes in the right side wall 69R, attaching the electrode member 117 to the right side wall 69R.

[00259] Due to this structure, the end portion of the developing roller shaft 52 slidably contacts the inner peripheral surface of the developing roller shaft cover portion 118. Similarly, the end portion of the supply roller shaft 50 slidably contacts the inner peripheral surface of the supply roller shaft cover 127 .

[00260] When the process cartridge 20 with the developing cartridge 30 provided therein is installed in the main casing 2, the developing bias terminal 131 as a feed-in member provided in the main casing 2 elastically contacts the contact plate 122, as shown by the dotted line in FIG. 15 .

[00261] More specifically, the contact plate 122 is provided in the vicinity of the supply roller shaft 50 inserted into the supply roller shaft cover portion 127 with respect to the vertical direction. The developing bias terminal 131 elastically contacts the contact plate 122 on its surface opposite to the surface facing the supply roller shaft 50 .

[00262] The developing bias terminal 131 is connected to a high-voltage wiring board provided in the main casing 2 to apply a developing bias. When the developing bias terminal 131 elastically contacts the upper surface of the contact plate 122, the developing bias from the high voltage wiring board is applied to the developing roller shaft through the electrode member formed of conductive resin. Then, a developing bias is applied from the developing roller shaft 52 to the conductive rubber roller body 53 .

[00263] The electrode member 117 supports the developing roller shaft 52 and the supply roller shaft 50 so that the same bias voltage as the developing bias voltage is applied to the conductive sponge roller body 51 through the supply roller shaft 50.

(4) relative position of input gear and electrode member

11, 13 and 15, in the developing cartridge 30, when the input gear 94 protrudes in a direction parallel to the developing roller shaft 52, that is, the first direction, the contact plate 122 of the electrode member 117 is disposed in the protruding plane.

[00265] More specifically, as shown in FIGS. 19 and 20, when the driven coupling portion 100 of the input gear 94 protrudes in the first direction, the contact plate 122 of the electrode member 117 is disposed within the protruding plane. In addition, when the driven coupling portion 100 protrudes in the first direction, the contact plate 122 is provided to contact the developing bias terminal 131 within the protruding plane. In particular, the contact plate 122 is provided to contact the developing bias terminal 131 on an extension line (second axis X2 described below) of the input gear support shaft 99 on which the drive coupling 100 is rotated.

[00266] As shown in FIG. 11, the first axis X1 which is the axis of the developing roller shaft 52 and the second axis X2 which is the axis of the input gear 94 are arranged parallel and equidistant in the front-rear direction. The pair of contact plates 122 of the electrode member 117 are disposed on the second axis X2. More specifically, as shown in FIG. 13, the first line L1 connects the axis of the input gear support shaft 99 on which the input gear rotates and the axis of the developing roller 38 on which the developing roller 38 rotates in a direction perpendicular to the axial direction of the developing roller shaft 52. The axis of the developing roller shaft 52 . As shown in FIG. 15, the second line L2 connects the contact point of the contact plate 122 with the developing bias terminal 131 which is a part of the contact plate 122 of the electrode member 117 and the developing roller 38 in a direction perpendicular to the axis of the developing roller shaft 52. The axis of the developing roller shaft 52 that rotates on it. As shown in FIG. 11 , the first line L1 and the second line L2 are parallel to each other. The distance D1 between the first axis X1 and the second axis X2 on the first line L1 shown in FIG. 13 and the distance D1 between the first axis X1 and the second axis X2 on the second line L2 shown in FIG. 15 The distance D2 between them is equal.

The effect of (5) developing box

In the developing cartridge 30 having the above structure, when the input gear 94 protrudes in a direction parallel to the developing roller shaft 52, that is, the first direction, the contact plate 122 of the electrode member 117 is disposed in the protruding plane. More specifically, when the driven coupling part 100 protrudes in the first direction, the contact plate 122 of the electrode member 117 is disposed within a protruding plane. In some aspects, when the driven coupling part 100 protrudes in the first direction, the contact plate 122 contacts the developing bias terminal 131 within a protruding plane. In particular, the contact plate 122 contacts the developing bias terminal 131 on the extension line of the input gear support shaft 99 on which the drive coupling 100 rotates. Furthermore, the first axis X1 and the second axis X2 are parallel to each other. A part of the contact plate 122 of the electrode member 117 is disposed on the second axis X2. More specifically, the first line L1 and the second line L2 are parallel to each other, and the first distance D1 and the second distance D2 are equal.

[00268] Therefore, when the driving force from the motor is input from the driving coupling portion 200 to the driven coupling portion 100, even when such a rotational force or torsional force that generates rotation or twisting of the developing cartridge 30 around the input gear 94 is applied When on the developing cartridge 30 , it is also possible to prevent a significant influence of rotational force and torsion force on the contact plate 122 of the electrode member 117 . As a result, it is possible to prevent the contact plate 122 from being in an inappropriate position. In this way, the contact plate 122 and the developing bias terminal 131 are in stable contact with each other so that electric power is stably supplied from the electrode member 117 to the developing roller shaft 52 .

[00269] If the contact point between the contact plate 122 and the developing bias terminal 131 is placed at any position in the protrusion plane when the driven coupling portion 100 protrudes in the first direction, the influence of the rotational force or the torsion force can be eliminated. reduced to a minimum.

[00270] Furthermore, in the developing cartridge 30, each end of the developing roller 38 is supported on the left and right side walls 69L by rotatably supporting each end of the developing roller shaft 52 in the left and right side walls 69L, 69R, 69R. Accordingly, when the developing roller 38 is firmly supported, the developing bias can be stably applied to the rubber roller body 53 .

[00271] One end of the developing roller shaft 52 is rotatably supported in the developing roller shaft insertion portion 111 of the gear cover 93 through a ring member 116. The other end of the developing roller shaft 52 is rotatably supported in the developing roller shaft cover portion 118 of the electrode member 117 . Each end of the developing roller 38 is also supported by the developing roller shaft insertion portion 111 of the gear cover 93 or the developing roller shaft covering portion 118 of the electrode member 117 . Thus, when the developing roller shaft 52 is effectively inserted into the developing roller shaft inserting portion 111 of the gear cover 93 and the developing roller shaft covering portion 118 of the electrode member 117, the developing roller 38 can be stably supported. Therefore, the developing bias can be stably applied to the rubber roller body 53 .

[00272] In the developing cartridge 30, the electrode member 117 is composed of a conductive resin. Therefore, the electrode member may be formed in any shape to stably apply the developing bias to the rubber roller body 53 .

[00273] The developing bias terminal 131 elastically contacts the upper surface of the contact plate 122 when the process cartridge 20 with the developing cartridge 30 provided therein is mounted in the main casing 2. The high voltage circuit board applies a developing bias voltage from the developing bias terminal 131 to the developing roller shaft 52 through the electrode member 117 . Then, a developing bias is applied from the developing roller shaft 52 to the conductive rubber roller body 53 . Thus, the developing bias can be stably applied from the electrode member 177 to the rubber roller body 53 .

[00274] The developing roller shaft 52 is made of metal so that a developing bias voltage can be more reliably applied from the electrode member 117 to the rubber roller body 53. In addition, in the developing cartridge 30 , the developing roller shaft cover 118 of the electrode member 117 rotatably supports the developing roller shaft 52 . Therefore, it is not necessary to support the developing roller shaft 52 with other members or parts. In this way, a reduction in parts count and cost savings can be achieved.

[00275] In the developing cartridge 30, the input gear 94 is integrally provided with the driven coupling portion 100 and the driving gear 101. Therefore, when the driven coupling 100 can reliably receive the driving force from the driving coupling 200 , the driving gear 101 transmits the driving force to the supply roller driving gear 95 , the developing roller driving gear 115 and the intermediate gear 96 . Thus, the supply roller shaft 50 and the developing roller shaft 52 and the agitator shaft 46 can be reliably rotated.

[00276] The driven coupling 100 has a hollow cylindrical shape. The driven coupling portion 100 is formed as a gear tooth having an engagement stop portion 102 extending radially inward from an inner peripheral surface of the driven coupling portion 100 . Therefore, when the engagement stopper 102 is engaged with the drive coupling 200 , it is possible to reliably receive the driving force from the drive coupling 200 .

[00277] When the driving gear 101 of the input gear 94 directly meshes with the developing roller driving gear 115, the driving force input to the input gear 94 from the driving coupling 200 is directly transmitted from the input gear 94 to the developing roller driving gear 115. Therefore, the developing roller 38 can be reliably rotated. Furthermore, when the driving force is thus transmitted, the driving force from the main casing 2 is not directly transmitted to the developing roller driving gear 115, so the developing roller shaft 52 can serve as a guide. More specifically, when the developing cartridge 30 is mounted in the developing cartridge mounting portion 147 , the ring member 116 provided on the developing roller shaft 52 and the developing roller shaft cover 118 are guided along the guide groove 153 . In this way, the developing roller shaft 52 can serve as a guide. Therefore, there is no need to additionally provide guides, and the number of parts used and the cost can be reduced.

[00278] The drive gear 101 of the input gear 94 also directly meshes with the supply roller drive gear 95 so that the drive force input from the drive coupling 200 to the input gear 94 is directly transmitted to the supply roller drive gear 95. Therefore, the supply roller can be reliably rotated. Furthermore, since the driving force is thus transmitted, the driving force is directly transmitted from the input gear 94 to the developing roller driving gear 115 and the supply roller driving gear 95 . Thus, the driving force can be efficiently transmitted, and the developing roller 38 and the supply roller 37 can be efficiently rotated.

[00279] The electrode member 117 is equipped with a developing roller shaft cover 118 and a supply roller shaft cover 127. Therefore, the developing roller shaft 52 and the supply roller shaft 50 can be reliably supported by the developing roller shaft cover 118 and the supply roller shaft cover 127 , respectively.

[00280] When the developing cartridge 30 is mounted in the main casing 2, the developing bias terminal 131 elastically contacts the upper surface of the contact plate 122 positioned between the developing roller shaft cover 118 and the supply roller shaft cover 127. above and opposite to the surface facing the supply roller shaft 50 . Therefore, reliable contact between the developing bias terminal 131 and the contact plate 122 can be achieved. In this way, the developing bias can be reliably applied to the contact plate 122 by the high-voltage wiring board (not shown) through the developing bias terminal 131 .

[00281] When the developing cartridge 30 is mounted in the developing cartridge mounting portion 147 of the drum frame 58, the front end of the protrusion 132 contacts the associated pressure lever 150. Each protrusion 132 is pressed backward by the associated pressure lever 150 by the urging force of the compression spring pushing the pressure lever 150 . In this way, the developing roller 38 is pressed against the photoconductive drum 28 . Due to the reliable contact between the developing roller 38 and the photoconductive drum 28 , the toner carried on the developing roller 38 can reliably develop the electrostatic latent image formed on the photoconductive drum 28 .

[00282] Each protrusion 132 extends outward in the first direction from the outer surface of each of the left and right side walls 69L, 69R at the front lower sides of the left and right side walls 69L, 69R. Due to this structure, the protrusion 132 can reliably contact the associated pressure lever 150, so that reliable contact between the developing roller 38 and the photoconductive drum 28 can be ensured.

[00283] The developing cartridge 30 is detachably installed in the drum cartridge 27. Regardless of the life of the photoconductive drum 28, the developing cartridge 30 can be replaced with a new developing cartridge according to the remaining toner amount. Regardless of the amount of remaining toner contained in the developing cartridge 30, the drum cartridge 27 can be replaced according to the life of the photoconductive drum 28.

[00284] 3. other aspects

(1) Electrode members according to other aspects

In the above description, the electrode member 117 as an electrode including the attachment plate 120 , the developing roller shaft cover portion 118 and the terminal portion 119 is integrally formed of conductive resin as shown in FIGS. 6 , 8 , and 15 . However, the attachment plate 120 , the developing roller shaft cover portion 118 and the terminal portion 119 may also be formed separately and then assembled together into the electrode member 117 .

[00285] For example, the terminal portion 199 equipped with the base 121 and the contact plate 122 may be integrally formed of metal as an electrode. The attachment plate 120 and the developing roller shaft cover 118 may be integrally formed of a conductive resin as a conductive member. Terminal portion 119 may then be fastened to attachment plate 120 by screws 130 . The electrode member 117 can be thus formed.

[00286] With this electrode member 117, since the terminal portion is made of metal, the developing bias can be reliably applied from the developing bias terminal 131 to the contact plate 122. Electric power can be reliably supplied from the terminal portion 119 that is a part of the electrode member 117 to the developing roller shaft 52 through the attachment plate 120 and the developing roller shaft cover portion 118 .

[00287] The terminal portion 119 indirectly contacts the developing roller shaft 52 through the attachment plate 120 and the developing roller shaft cover portion 118. Therefore, the position of the terminal portion 119 relative to the developing roller shaft 52 or the position of the developing roller shaft 52 relative to the terminal portion 119 can be freely selected. In this way, electric power can be reliably supplied from the contact plate 122 to the developing roller shaft 52 while improving design efficiency.

[00288] (2) The developing roller shaft according to other aspects

In the above description, the developing roller shaft 52 is made of metal. However, the developing roller shaft 52 may also be composed of conductive resin. In addition, the developing roller shaft 52 may also be formed of an insulating material such as an insulating resin material.

[00289] When the developing roller shaft 52 is made of an insulating material, the electrode member 117 and the rubber roller body 53 can be electrically connected, so that a developing bias can be directly applied from the electrode member 117 to the rubber roller body 53. In this way, the electrical resistance of the rubber roller body 53 can be set lower than that of the rubber roller body 53 according to the various aspects described above.

[00290] For example, as shown in FIG. 18, the surface of the insulating developing roller shaft 52A may be covered with a conductive sheet 154 made of metal foil such as aluminum foil to be in contact with the rubber roller body 53. The conductive sheet 154 may contact the inner peripheral surface of the developing roller shaft covering part 118 . Due to this structure, a developing bias can be applied from the electrode member 117 to the rubber roller body 53 through the conductive sheet 154 .

[00291] (3) Input gear according to other aspects

In the above description, the driven coupling portion 100 and the driving gear 101 are integrally formed on the input gear 94 . However, the input gear 94 may be integrally formed with, for example, the drive gear 101 and the engagement stopper 102 .

[00292] FIG. 21 is a perspective view of the developing cartridge corresponding to FIG. 6, in which the electrode member is removed from the developing cartridge; FIG. 22 is a perspective view of the developing cartridge corresponding to FIG. 8, in which the electrode member is removed from the developing cartridge ; FIG. 23 is a right side view of the developing cartridge corresponding to FIG. 15 . Fig. 24 is a cross-sectional view of the developing cartridge taken along line A-A in Fig. 23, and Fig. 25 is a cross-sectional view of the developing cartridge along line B-B in Fig. 23.

[00293] A developing cartridge according to some other aspects will be described in detail below with reference to FIGS. 21 and 25. FIG. It should be noted that like reference numerals designate like components, and thus detailed descriptions thereof are omitted.

(1) developing frame

The developing cartridge 30 according to some aspects has a developing frame 36 similar to the developing cartridge 30 of the above-described aspect except for the following structure.

[00295] As shown in FIGS. 21 and 22, the developing frame 36 of some aspects has a cylindrical screw portion 79 as a screw portion for attaching the electrode member 117 to the right side wall 69R, closing one side of the developing chamber 42. side (right side). The cylindrical screw portion 79 has a cylindrical shape extending outward from the right side wall 69R. A screw groove is formed on the inner peripheral surface of the cylindrical screw portion 79 for screwing the shaft 130 a of the screw 130 into the cylindrical screw portion 79 . The upper and lower ends of the free end 79 a of the cylindrical screw portion 79 are cut off along the front-rear direction. Thus, the free end 79a is substantially elliptical and has flat portions extending in the front-rear direction at its upper and lower ends.

(2) gear mechanism portion and gear cover

The developing cartridge 30 according to some aspects has the gear mechanism portion 92 and the gear cover 93 similar to the developing cartridge 30 according to the above-described aspects.

[00297] (3) electrode member

The developing cartridge 30 according to some aspects has the electrode member 117 similar to the developing cartridge 30 according to the previously described aspect except for the following structure.

[00298] On the front side of the bearing member 201, an opening 161 is formed. When the bearing member 201 is attached to the right side wall 69R, the developing roller shaft 52 is inserted into the ring portion 202 and the supply roller shaft 50 is inserted into the opening 161 . In order to prevent the cylindrical screw portion 79 extending outward from the right side wall 69R in the first direction from interfering with the bearing member 201 , a part of the outer circumference of the bearing member 201 where the cylindrical screw portion 79 extends is cut off. When the bearing member 201 is attached to the right side wall 69R, the cylindrical screw portion 79 is exposed from the outer periphery of the bearing member 201 .

[00299] As an electrode for applying a developing bias to the developing roller shaft 52, an electrode member 117 is provided on the right side wall 69R separately from the bearing member 201 so that a part of the bearing member 201 is inserted between the right side wall 69R and the electrode member 117. between. As shown in FIG. 24 , the substrate 123 as the attachment portion of the electrode member 117 is disposed at a position outside the attachment plate 120 parallel to the attachment plate 120 with respect to the first direction. As shown in FIGS. 21 and 22, a screw hole 140 as an insertion portion is formed at a substantially central portion of the base plate 123. As shown in FIG. In relation to the free end 79a of the cylindrical screw portion 79, the screw hole 140 is substantially elliptical with a flat portion extending in the front-rear direction.

[00300] The peripheral plate 124 extends from the periphery of the base plate 123 in the first direction so as to connect the base plate 123 and the attachment plate 120. In the developing cartridge 30 according to some aspects, the electrode member 117 is attached to the right side wall 69R in the manner described below. First, the end portions of the developing roller shaft 52 and the supply roller shaft 50 are inserted into the developing roller shaft cover 118 and the supply roller shaft cover 127 , respectively. Simultaneously, the cylindrical screw portion 79 provided on the right side wall 69R is inserted into the screw hole 140 on the base plate 123 , fitting the free end 79 a of the cylindrical screw portion 79 into the screw hole 140 . Then, a screw 130 as a fixing member is screwed into the cylindrical screw portion 79 exposed from the base plate 123 .

[00301] The screw 130 is integrally formed with a shaft 130a having threads formed in the axial direction, and a screw head that is disposed on the end of the shaft 130a, extending in the radial direction of the shaft 130a like a mushroom, as a separation prevention part 130b. The diameter of the screw head 130 b is the same as or slightly larger than the diameter of the cylindrical screw portion 79 .

[00302] As shown in FIGS. 24 and 25, the threaded part 130 is screwed into the cylindrical screw part 79 until the inner end surface If of the threaded part head 130b as the second end face in the axial direction of the threaded part 130 contacts the cylindrical screw part The free end surface Ff of the portion 79 as the third end surface.

[00303] When the electrode member 117 is thus attached to the right side wall 69R, the attachment plate 120 provided between the developing roller shaft cover 118 and the base 121 contacts the bearing member 201, so that the electrode member 117 is opposed to the first direction (the width direction of the developing cartridge 30). The free end surface Ff of the cylindrical screw portion 79 is provided to protrude slightly outward (for example, 0.2 mm) in the first direction from the outer surface of the base plate 123 as the first end surface toward the side of the screw head 130b.

[00304] With respect to the axial direction of the screw 130, the inner end surface If of the screw head 130b is set to contact the free end surface Ff of the cylindrical screw part 79 and face the outer surface Of of the base plate 123, with the upper and lower sides of the screw shaft 130a separated by a small distance (eg 0.2mm). At a position opposite to the free end face Ff of the cylindrical screw portion 79 , the screw head 130 b restricts or prevents separation or removal of the base plate 123 from the cylindrical screw portion 79 .

[00305] Due to the distance between the inner end surface If of the screw head 130b and the outer surface Of of the substrate 123, the electrode member 117 does not come into close contact with the outer surface Of of the substrate 123. Therefore, the electrode member 117 can move slightly in association with the slight gap between the electrode member 117 and the cylindrical screw portion 79 . When the developing bias terminal 131 provided in the main casing 2 elastically contacts the upper surface of the contact plate 122 , the developing roller shaft covering portion 118 is slightly in the range where there is a slight gap between the electrode member 117 and the cylindrical screw portion 79 . to move. Therefore, the outer peripheral surface of the end portion of the developing roller shaft 52 is in slidable and close contact with the inner peripheral surface of the developing roller shaft cover portion 118 . Thus, the end portion of the developing roller shaft 52 is rotatably supported by the developing roller shaft cover 118 . The supply roller shaft cover 127 also moves within the range of this small gap. Therefore, the outer peripheral surface of the end portion of the supply roller shaft 50 is also in slidable and close contact with the inner peripheral surface of the supply roller cover 127 . In this way, the end portion of the supply roller shaft 50 is rotatably supported by the supply roller shaft cover 127 .

The effect of (4) developing box

As described above, in the developing cartridge 30, the electrode member 117 can be slightly moved within the range of a minute gap. When the developing bias terminal 131 provided in the main casing 2 elastically contacts the upper surface of the contact plate 122 , the developing roller shaft cover 118 moves within the range of the minute gap. Therefore, when the outer peripheral surface of the end portion of the developing roller shaft 52 is securely in contact with the inner peripheral surface of the developing roller shaft cover portion 118, the developing roller shaft 52 is rotated. In other words, the developing roller shaft covering portion 118 rotatably supports the developing roller shaft 52, and the electrode member 117 is moved so that when the developing bias terminal 131 contacts the contact plate 122, the developing roller shaft covering portion 118 reliably contacts the developing roller shaft. 52 contacts. Therefore, the developing bias is reliably applied from the developing bias terminal 131 to the developing roller shaft 52 through the contact plate 122 and the developing roller shaft covering portion 118 .

[00307] In the developing cartridge 30, the electrode member 117 is easily attached to the right side wall 69R with the screw 130 so that the electrode member can be slightly moved by a minute gap.

[00308] More specifically, when the screw head 130b with respect to the axial inner end face If of the screw 130 contacts the free end face Ff of the cylindrical screw part 79, the screw head 130b and the base plate 123 are arranged to be both There is a certain distance between them. In this way, the distance between the outer surface Of of the base plate 123 and the inner end surface If of the screw head 130b can be set accurately and reliably. Therefore, while ensuring smooth rotation of the developing roller shaft 52 relative to the developing roller shaft covering portion 118 , the developing roller shaft covering portion 118 can be reliably brought into contact with the developing roller shaft 52 .

[00309] In the developing cartridge 30, the developing roller shaft cover portion 118 and the contact plate 122 are provided to extend outward from the right side wall 69R along the developing roller shaft 52 in the first direction. Therefore, when the contact plate 122 is securely in contact with the developing bias terminal 131, the developing roller shaft 52 can be ensured to rotate smoothly relative to the developing roller shaft covering portion 118, and the developing roller shaft covering portion 118 can be reliably connected to the developing roller shaft 52. touch.

[00310] In the developing cartridge 30, the supply roller shaft cover 127 is provided in the electrode member 117. When the supply roller shaft 50 is rotatably supported by the supply roller shaft cover 127 , a developing bias may also be applied to the supply roller shaft 50 .

[00311] In the developing cartridge 30, the bearing member 201 is provided separately from the electrode member 117 on the right side wall 69R. Since the bearing member 201 can carry or support the developing roller shaft 52 , the developing roller shaft cover 118 can reliably contact the developing roller shaft 52 while ensuring the smooth rotation of the developing roller shaft 52 . Even when the bearing cannot be used as the electrode member 117, electric power can be reliably supplied to the developing roller shaft 52.

(5) electrode member according to other aspects

In the above description, since there is a distance between the inner end surface If of the screw head 130b and the outer surface Of of the base plate 123, the developing roller shaft cover 118 is moved so that its inner peripheral surface reliably contacts the end of the developing roller shaft 52. peripheral surface. However, the developing roller shaft cover 118 can be moved in a different manner so that its inner peripheral surface can reliably contact the outer peripheral surface of the end portion of the developing roller shaft 52 .

[00313] For example, before the electrode member 117 is attached to the right side wall 69R, the electrode member 117 may be formed such that the distance between the center of the screw hole 140 of the electrode member 117 and the axis of the developing roller shaft cover 118 is slightly Different from the distance between the axis of the cylindrical screw portion 79 and the axis of the developing roller shaft 52 . When the thus formed electrode member 117 is attached to the right side wall 69R, the center of the screw hole 140 and the axis of the cylindrical screw portion 79 match each other. However, the axes of the developing roller shaft cover 118 and the developing roller shaft 52 are slightly different from each other and do not match. Therefore, the outer peripheral surface of the end portion of the developing roller shaft 52 reliably contacts the inner peripheral surface of the developing roller shaft cover portion 118 .

[00314] While the invention has been described in conjunction with the various exemplary aspects outlined above, various alternatives, modifications, variations, improvements and/or substantial equivalents, whether known or presently unforeseen, would be apparent to those skilled in the art. of ordinary skilled artisan are obvious. Accordingly, the illustrative aspects of the invention described above are by way of illustration only and not limitation. Various changes may be made without departing from the spirit and scope of the invention. The present invention is therefore intended to embrace all known or later developed alternatives, modifications, variations, improvements and/or substantial equivalents.

[Description of reference symbols]

1: laser printer

2: Main housing

27: Drum Box

28: photoconductive drum

30: Developing box

36: Development frame

37: Supply roller

38: Developing roller

50: supply roller shaft

51: Sponge roller body

52: Developing roller shaft

53: Rubber roller body

69: side wall

79: Cylindrical screw parts

93: Gear Cover

94: Input gear

95: Supply roller drive gear

102: Engagement stop

100: driven coupling part

101: Drive gear

115: Developing roller drive gear

117: electrode member

118: Developing roller shaft cover

119: Terminal Department

120: Attachment plate

122: Contact plate

123: Substrate

127: Supply roller shaft cover

130: threaded parts

130b: screw head

132: Protrusion

140: Screw holes

150: pressure lever

201: Bearing components

X1: first axis

X2: second axis

L1: first line

L2: second line

D1: first distance

D2: second distance

If: The inner end surface of the head of the threaded part relative to the axial direction of the threaded part

Ff: Free end face of cylindrical threaded part

Of: Outer surface of the substrate.

Claims (7)

1. A developing cartridge (30), is characterized in that, comprises: a housing (36) comprising a first side wall (69R) and a second side wall (69L) opposite said first side wall (69R); A developing roller (38) disposed between the first side wall (69R) and the second side wall (69L), the developing roller (38) including a developing roller shaft ( 52) and a developing roller member (53) configured to carry developer thereon, said developing roller member (53) being arranged to surround said developing roller shaft (52) around said developing roller shaft (52) during development First axis (X1) rotation; an electrode (117) disposed on said first side wall (69R) adjacent to said developing roller shaft (52), said electrode (117) being electrically connected to said developing roller member (53); and The driven coupling part (94) provided on the second side wall (69L), the driven coupling part (94) is connected to the driving coupling part of the image forming apparatus (1) and is configured to go around the Second axis (X2) rotation, Wherein, the electrode (117) has a contact portion (122) configured as a feed-in member of the contact image forming apparatus (1); When the driven coupling portion (94) is projected in a direction parallel to the developing roller axis (52), at least a part of the contact portion (122) is provided in the projected portion. 2. The developing cartridge (30) according to claim 1, characterized in that an electrode (117) surrounds a circumferential portion of the developing roller shaft (52). 3. The developing cartridge (30) according to claim 1, characterized in that the developing roller (38) includes a developing roller gear (115) connected to rotate together with the developing roller shaft (52), and is driven by the coupling portion (94) includes drive gear (101) meshing with developer roller gear (115). 4. developer cartridge (30) as claimed in claim 3, is characterized in that, this / described developer cartridge (30) also comprises: a supply roller (37) configured to supply developer to a development roller (38), the supply roller (37) being disposed parallel to the development roller (38), Wherein, the supply roller (37) includes a supply roller shaft (50) configured to rotate during the developing process, a supply roller member (51) configured to supply developer to the developing roller (38), and the supply roller member (51) is arranged to Around the supply roller shaft (50), and a supply roller gear (95) connected for rotation with the supply roller shaft (50), the supply roller gear (95) is configured to mesh with the drive gear (101). 5. The developing cartridge (30) of claim 4, wherein the electrode (117) is electrically connected to the supply roller shaft (50). 6. The developing cartridge (30) as claimed in claim 5, wherein the electrode (117) has a first portion (118) configured to surround the circumferential portion of the developing roller shaft (52), and configured to surround the supply roller shaft The second portion (127) of the circumferential portion of (50). 7. The developing cartridge (30) according to claim 6, characterized in that, the contact portion (122) is disposed above the first portion (118) and the second portion (127).

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