JPH09197783A - Toner bottle - Google Patents

Abstract

(57) Abstract: To enable stable toner supply regardless of the amount of toner in a toner bottle. A toner bottle has a toner discharge port.
A is formed, and a spiral protrusion 38d is formed on the inner wall surface. The protrusions 38d are formed so that the pitch interval gradually narrows as they move away from the toner ejection ports 38a. This reduces the amount of conveyance on the bottom side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile, etc.
The present invention relates to a toner bottle as a toner container in a toner replenishing device.

[0002]

2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus, a developing device for visualizing an electrostatic latent image formed on an image carrier has a toner replenishing device for supplying toner to the developing portion. It is provided. The toner replenishing device of the most general developing device has a structure as shown in FIG. In the figure, reference numeral 100 is a photosensitive drum, 10
Reference numeral 2 denotes a developing device, 104 denotes a developing roller, and 106 denotes a paddle roller. The developing device 102 is provided with a toner cartridge 108 for containing toner and a toner hopper unit 110 for replenishing toner. The toner in 108 is supplied to the toner hopper unit 110 by the agitator 112. The toner is once replenished to the toner hopper unit 110 in order to keep the toner replenishment amount of the toner replenishing roller 114 to the developing unit 102a as constant as possible and to keep the toner density in the developing unit 102a constant.

In recent years, a small-sized, small-space structure has been developed in which a screw type toner bottle is horizontally mounted on a toner hopper portion formed in a developing device to supply toner. This screw type toner bottle has a spiral protrusion on the inner wall surface, and is rotated by mounting the toner discharge port side on the toner hopper. Due to the screw action of the protrusion, the toner inside is conveyed and discharged in one direction from the bottom side toward the toner discharge port side.

[0004]

However, it has been pointed out that in the above-mentioned screw type toner bottle, the replenishment amount varies depending on the amount of toner in the bottle, and stable replenishment to the developing unit cannot be achieved.

According to the consideration of the inventor of the present invention, this is a structure in which the toner is conveyed in one direction in the bottle. Therefore, when the amount of toner is large, the screw of the protrusion on the bottom side is located on the toner discharge port side. The action is also transmitted through the toner itself, that is, the toner itself exhibits a partial function of the screw,
As a result, it is predicted that the screw action is amplified and a large amount of toner is ejected. In other words, the instability of the replenishment amount is related to the shape of the spiral protrusion, and when the toner amount is small, the toner itself has a small chance of becoming a transmission member of the screw action, and therefore its influence is small. Although it is extremely small, it is predicted that it becomes remarkable when the amount of toner is large.

An object of the present invention is to provide a toner bottle capable of exhibiting a constant toner replenishing function regardless of the amount of toner in the bottle.

[0007]

According to the present invention, if the screw action on the bottom side is reduced, the screw action is not amplified on the toner discharge port side even if the amount of toner is large, and a stable replenishment function is provided. It is based on the idea that it can be obtained. Specifically, the invention according to claim 1 adopts a configuration in which the pitch interval of the protrusions on the bottom side is narrowed to reduce the transport amount. According to the second aspect of the invention, the height of the protrusion on the bottom side is reduced to reduce the carrying force. According to the first aspect of the invention, a configuration is adopted in which the rising angle of the mountain shape of the protrusion on the bottom side is made gentle to reduce the transport amount.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As shown in FIGS. 2 and 3, in the image forming apparatus 2, a process cartridge 4 which is detachably arranged in a main body of the image forming apparatus (not shown), and toner replenishment which is detachably arranged in the process cartridge 4. Device 6
The process cartridge 4 integrally houses a photoconductor 8 as an image carrier and a developing device 10. Around the photoconductor 8, a charging roller 12,
The developing device 10 includes a transfer roller 14, a cleaning blade 16 and the like.
0, a developing sleeve 22, a doctor blade 24, and the like. In FIG. 3, reference numeral 26 indicates a toner recycling belt, reference numeral 28 indicates a toner concentration sensor, and the toner recycling belt 26 is connected to the toner conveying coil 30.

Next, the image forming operation in the image forming apparatus 2 will be described with reference to FIG. The photoconductor 8 is neutralized by the neutralizing light 32, and its surface potential is averaged to a reference potential of 0 to -150V. Next, it is charged by the charging roller 12, and the surface potential becomes around -1100V. Next, the portion (image portion) exposed by the exposure light 34 and irradiated with the light has a surface potential of 0 to −−.
It becomes 290V. Since a bias voltage of about -800 V is applied to the developing sleeve 22, the developing sleeve 2
The toner on 2 adheres to the image portion. The photoreceptor 8 on which the toner image is formed is rotated, and the transfer paper is fed from a paper supply unit (not shown) at a timing such that the leading end of the paper and the leading end of the image coincide with each other at the transfer roller 14.
The toner image on the surface of the photoconductor 8 is transferred to the transfer paper at a portion.
After that, the transfer paper is sent to a fixing unit (not shown), and the toner is fused to the transfer paper by heat and pressure and discharged as a copy. Residual toner remaining on the photoconductor 8 is scraped off by the cleaning blade 16, and then the photoconductor 8 is neutralized with residual charge by the neutralization light 32 to be in a toner-free state, and the process proceeds to the next image forming step again. .

The above-described photoconductor 8, charging roller 12, developing device 10, cleaning blade 16 and the like are housed in an integral photoconductor case 36, as shown in FIG. The residual toner collected by the cleaning device having the cleaning blade 16 is conveyed by the toner conveying coil 30 and is sent by the toner recycle belt 26 to the developer stirring section having the stirring screws 18 and 20, whereby the toner is recycled. ing.

Next, the developing device 10 will be described. The developing sleeve 22 has a fixed shaft in which five-pole magnets are arranged, and the outer peripheral surface is covered with a non-magnetic pipe material.
As the pipe material rotates, the developer is transferred to the developing sleeve 2.
Move up 2. The developer is a two-component type composed of small iron balls called carrier and toner. The developer circulates while being stirred by the stirring screws 18 and 20, whereby the toner has a charge, adheres to the carrier and is carried to the surface of the photoconductor 8, and can be adhered to the photoconductor 8 by the action of electrostatic force. Of the developer, the carrier circulates, but the toner is consumed because it adheres to the image portion on the photoconductor 8. Therefore, it is necessary to replenish it appropriately. If the amount of the developer supplied to the photoconductor 8 is not constant, the image density becomes defective and the density becomes uneven. Therefore, the doctor blade 24 is arranged to regulate the inflow amount of the developer.

As shown in FIG. 2, the toner replenishing device 6 generally includes a toner bottle 38 as a toner container.
And the toner bottle 3
8 is provided with a pedestal 42 that accommodates 8 and a bottle holding member 44 that is attached to the toner hopper 40 and rotates integrally with the toner bottle 38. The bottle holding member 44 has a plurality of pushing members 46. . An opening portion 48 is formed in the toner hopper portion 40, and a replenishment amount regulating member 50 having elasticity for adjusting the toner replenishment amount is provided on the outer surface of the opening portion 48. A toner introduction cover 52 is attached to the outside of the opening 48, and a toner supply port 54 that opens horizontally is formed at the lower end of the toner introduction cover 52. The toner supply port 54 corresponds to the toner introduction unit 55 of the developing device 10.

The toner flowing out from the toner discharge port of the toner bottle 38 to the toner hopper portion 40 (arrow A) is pushed up by the pushing member 46 of the bottle holding member 44 (arrow B), passes through the opening 48, and the toner introducing cover 52 is provided. It enters (arrow C), and is replenished into the developing device 10 through the toner supply port 54 and the toner introduction portion 55 which are in communication with each other (arrow D).

Next, the toner supply device 6 will be described in detail with reference to FIGS. FIG. 5 is an external view of a main part of the toner replenishing device 6 mounted on the process cartridge 4, and FIG. 6 is a component configuration diagram of the toner replenishing device 6. As shown in FIG. 5, the toner replenishing device 6 includes a front plate 5 of the device body.
7 and a guide plate (not shown) attached to the rear plate 58 of the apparatus main body. A stopper 59 for preventing the toner replenishing device 6 from coming off is attached to the front part of the guide plate. The toner bottle 38 is rotationally driven by a driving unit 60 fixed to the rear plate 58 of the apparatus main body. The drive unit 60 includes a joint 62 and a spring 6
4, a case portion 66 having a motor and a shaft built therein, and a concave portion 62a and a convex portion 6 at the tip of the joint 62.
2b and 62b are formed. Correspondingly, at the bottom portion (rear end) of the toner bottle 38, a columnar convex portion 38b that enters the concave portion 62a of the joint 62 and a prismatic convex portion 38c that engages with the side surface of the convex portion 62b are formed. The bottom of the toner bottle 38 is held by fitting the cylindrical convex portion 38b into the concave portion 62a, and the prismatic convex portion 3 with respect to the convex portion 62b is held.
The rotation of the toner bottle 38 is obtained by the engagement of 8c. When the joint 62 of the drive unit 60 rotates in the direction of arrow E, the toner bottle 38 also rotates in the same direction (FIG. 5).

A spiral protrusion 38d is formed on the inner wall surface of the toner bottle 38. When the toner bottle 38 is rotated, the screw action of the protrusion 38d conveys the toner in the bottle from the bottom side toward the toner discharge port side. Then, the toner is discharged from the toner discharge port 38a. A cap 68 for preventing toner from being ejected when not in use is provided on the toner ejection port 38a.
Is embedded. A plurality of ribs 44a are integrally formed on the tip end side of the bottle holding member 44, and the pushing member 46 is attached to these ribs 44a with a double-sided tape or the like. The pushing member 46 is made of an elastic material such as mylar or rubber. A rib 44b is formed on the inner wall surface of the bottle holding member 44, and the rib 44b is hooked on a flat surface portion 38e provided on the head of the toner bottle 38 so that the both rotate integrally.

In FIG. 6, reference numeral 70 is a collet chuck for picking up and separating the cap 68, which is built in the cylindrical case 72 and is integrated with the shaft member 76 by the screw 74. Reference numeral 78 is a seal material, 80 is a seal member, and 82 is a coil spring that constantly presses a series of components such as the collet chuck 70, the cylindrical case 72, and the shaft member 76 toward the toner bottle 38 side. These assembled parts are held in the toner hopper section 40. Reference numeral 84 is a cap 68
Is a handle for opening and closing, and an integrally formed shaft portion 84a is formed in a shaft hole 42a formed at the tip of the pedestal 42.
It is supported by and can be rotated. Reference numerals 42b and 42
Reference numeral c indicates a hole that engages with a positioning pin provided on the guide plate. Further, reference numeral 86 is a slide shaft that enters a hole 76a formed in the shaft member 76, and is in contact with a cam portion 84b formed in the handle 84,
5 is rotated in the F direction shown in FIG. 5 and a series of parts such as the collet chuck 70 is slid in a direction away from the toner bottle 38, the cap 68 causes the toner discharge port 38 to move.
The toner in the toner bottle 38 escapes from the a and flows into the toner hopper 40 (FIGS. 7 and 8). Details of this will be described later. As shown in FIG. 6, the toner hopper unit 40
The supply amount regulating member 50 provided in the opening 48 of the slit hole 5 is made of an elastic material such as mylar or rubber.
It has 0a (long and narrow square hole with vertical width w). By setting the width of the slit hole 50a, the toner supply amount is made appropriate. The replenishment amount regulating member 50 is attached to the opening 48 with double-sided tape or the like.

As shown in FIG. 1, the protrusions 38d formed on the inner wall surface of the toner bottle 38 are, in other words, as the pitch distances from the toner discharge ports 38a, in other words, as shown in FIG.
It is formed so that it gradually narrows toward the bottom side. In this embodiment, P ₁ = 20 mm and P ₂ = 1
7 mm, P ₃ = 14 mm, P ₄ = 11 mm, P ₅ = 9 m
It is set to m. When the toner bottle 38 rotates, the toner inside is sent in one direction from the bottom side toward the toner discharge port 38a side by the screw action of the protrusion 38d, but the pitch of the protrusions 38d becomes narrower on the bottom side. Therefore, the conveyance speed is slower and the conveyance amount is smaller than that on the toner ejection port 38a side. Therefore, even when the amount of toner is large, the toner discharge port 38 due to the large amount of conveyance from the bottom side.
Excessive ejection on the a side is suppressed. When the amount of toner is small, the toner itself has little chance of becoming a transmission member of the screw action, and therefore there is almost no effect of narrowing the pitch interval. Therefore, regardless of the amount of toner in the bottle, it is possible to always stably supply toner.

Next, the toner replenishment from the toner replenishing device 6 to the process cartridge 4 will be described. FIG. 7 shows a state in which the toner replenishing device 6 and the process cartridge 4 are attached to the main body of the image forming apparatus. Toner bottle 3
The head of No. 8 is positioned by the engagement of the spherical protrusion 38f with the bottle holding member 44 and the contact with the rib 44c of the bottle holding member 44. From this state, when the handle 84 is rotated downward as shown by the arrow F in FIG. 5,
The cam portion 84b pulls the slide shaft 86 in the J direction shown in FIG. As a result, the shaft member 76 also starts to move in the J direction, and the collet chuck 70
As a result, the collet chuck 70 starts closing and the cap 68 is picked. When the movement in the J direction further proceeds in this state, as shown in FIG.
The cap 68 of the toner bottle 38 is removed by the collet chuck 70, and the toner in the toner bottle 38 flows out into the toner hopper portion 40 of the receiving table 42 (if the toner in the toner bottle 38 is small, it does not flow out). This state is a state where the setting of the toner supply device 6 is completed.

Toner replenishment is performed by detecting the toner concentration in the developing device 10 by the toner concentration sensor 28. When the detected value falls below the reference concentration, the drive unit 6
0 operates to rotate the joint 62 in the direction of arrow E. As a result, the joint 62 engages with the bottom of the toner bottle 38, and the toner bottle 38 also rotates in the same direction. When the toner bottle 38 rotates, the toner discharge port 38
The toner is ejected from a and accumulated in the toner hopper section 40. On the other hand, rotation of the toner bottle 38 is caused by rotation of the bottle holding member 4.
4 and the pushing member 46 is slidably rotated on the inner wall surface of the toner hopper portion 40 by being transmitted through the ribs 44b integral with the toner 4 and scrapes up the toner accumulated in the toner hopper portion 40. When the push-out member 46 passes through the slit hole 50a of the replenishment amount regulation member 50, the toner is discharged from the slit hole 5a.
It is pushed out from 0a. The pushed toner drops inside the toner introducing cover 52, and is replenished into the developing device 10 through the toner supply port 54 and the toner introducing portion 55 located below.

FIG. 9 shows an embodiment corresponding to claim 2. The toner bottle 39 shown in this example has a toner discharge port 39a, and the spiral protrusion 3 is formed on the inner wall surface.
9b is formed. The protrusions 39b are formed at equal intervals, but the protrusions 39b are formed so that the height of the protrusions 39b gradually decreases as the distance from the toner discharge port 39a increases. Specifically, h ₁ = 5 mm, h ₂ =
4.7 mm, h ₃ = 4.4 mm, h ₄ = 4.1 mm, h
₅ = 3.8 mm is set. In the case of this example as well, as in the above-described embodiment, the carrying amount on the bottom side is small, so even if the amount of toner in the bottle is large, the toner discharge port 39a is
Excessive discharge on the side is suppressed.

FIG. 10 shows an embodiment corresponding to claim 3. The toner bottle 41 shown in this example has a toner discharge port 41a, and a spiral protrusion 41b is formed on the inner wall surface. The protrusions 41b are formed at evenly spaced pitches, but the protrusions 41b are formed so that the rising angle of the mountain shape gently inclines as the protrusions 41b move away from the toner ejection port 41a. Specifically, θ ₁ =
40 °, θ ₂ = 45 °, θ ₃ = 50 °, θ ₄ = 55 °,
θ ₅ = 60 ° is set. In the case of this example as well, the carrying amount on the bottom side is small as in each of the above-described embodiments, so that even if the amount of toner in the bottle is large, the toner discharge port 41a
Excessive discharge on the side is suppressed.

[0022]

According to the first aspect of the present invention, the pitch interval of the spiral projections formed on the inner wall surface of the toner bottle is gradually narrowed as the distance from the toner discharge port side increases. The amount of conveyance on the bottom side is reduced, so that even if the amount of toner in the bottle is large, excessive ejection from the toner ejection port can be prevented, and stable toner supply can be performed. According to the invention described in claim 2, the height of the spiral protrusion formed on the inner wall surface of the toner bottle is
Since it is configured to gradually lower as it moves away from the toner discharge port side, the amount of conveyance on the bottom side is reduced, and even when the amount of toner in the bottle is large, excessive discharge from the toner discharge port can be prevented, and stable toner can be obtained. Can be replenished. According to the third aspect of the present invention, since the rising angle of the mountain shape of the spiral protrusion formed on the inner wall surface of the toner bottle is gradually inclined as it goes away from the toner discharge port side, Transport amount is reduced,
As a result, even when the amount of toner in the bottle is large, it is possible to prevent excessive ejection from the toner ejection port, and it is possible to perform stable toner supply.

[Brief description of drawings]

FIG. 1 is a side view of a toner bottle showing an embodiment of the present invention.

FIG. 2 is a schematic sectional view of an image forming apparatus.

FIG. 3 is a partially omitted perspective view of a process cartridge.

FIG. 4 is a perspective view of a process cartridge.

FIG. 5 is a perspective view of a toner replenishing device.

FIG. 6 is an exploded perspective view of the toner supply device.

FIG. 7 is a diagram showing a toner replenishing operation in the toner replenishing device, and is a cross-sectional view of a state in which the toner bottle is attached to the toner hopper portion.

FIG. 8 is a cross-sectional view showing a toner replenishing operation in the toner replenishing device in a state where the cap of the toner bottle is pulled out by the collet chuck and the toner flows out into the toner hopper portion.

FIG. 9 is a side view of a toner bottle showing an embodiment corresponding to claim 2.

FIG. 10 is a side view of a toner bottle showing an embodiment corresponding to claim 3;

FIG. 11 is a schematic sectional view of a conventional toner supply device.

[Explanation of symbols]

 38d, 39b, 41b Projection parts 38a, 39a, 41a Toner discharge port 40 Toner hopper part

Claims (3)

[Claims] 1. A toner is conveyed from the bottom side toward the toner ejection port side by being rotationally driven in a state where the inner wall surface has a spiral protrusion and the toner ejection port side is attached to a toner hopper section of an image forming apparatus. In the toner bottle described above, the pitch interval of the protrusions is formed so as to become gradually narrower as the distance from the toner discharge port side increases. 2. An inner wall surface is provided with a spiral projection, and the toner is discharged from the bottom side in the direction of the toner discharge port by being driven to rotate while the toner discharge port side is attached to the toner hopper of the image forming apparatus. In the toner bottle described above, the peak height of the protrusion is gradually lowered as the distance from the toner discharge port side increases. 3. A spiral projection is provided on the inner wall surface, and the toner is discharged from the bottom side toward the toner discharge port side by being driven to rotate while the toner discharge port side is attached to the toner hopper part of the image forming apparatus. In the toner bottle, the rising angle of the chevron of the protrusion is formed so as to gently incline as it goes away from the toner discharge port side.