JP2009216989A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which supplies developers of different colors to a developing member while switching them. <P>SOLUTION: When a developing device 34 visualizes an electrostatic latent image with the developers, a developing roll 68 rotates while bearing developer supplied from a developer supply section 80 located in a developer supply position. When the visualization with the developers finishes, the developing device 34 opens an opening/closing member 90 by the rotation (less than 90°) of a rotor 66 under the control exerted by a control section 62. The developer supply section 80 also moves outside the range where the magnetic force of a developer supply magnetic pole of the developing roll 68 acts, thereby stopping the supply of magenta developer from the developer supply section 80 to the developing roll 68. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus.

  Patent Document 1 discloses a liquid developing apparatus that allows a developer and a cleaning liquid to be alternately circulated in a developing device by using a single developing device and a single vacuum pump, thereby enabling development of a plurality of colors. .

JP-A-5-158321

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus capable of switching and supplying different color developers to a developing member.

  In order to achieve the above object, the present invention according to claim 1 is different in color from a developing member that includes an image carrier and a magnet and supplies the developer held by the magnetic force of the magnet to the image carrier. A plurality of developer supply units that individually supply the developer to the developing member according to the magnetic force of the magnet, a rotating body that is provided with the plurality of developer supply units and rotates about a rotation axis; Peeling means for peeling off the developer remaining after the developing member has supplied to the image carrier from the developing member; recovery means for collecting the developer peeled off by the peeling means; and the plurality of developer supplying sections. Control means for switching between a state in which the developer is supplied to the developing member and a state in which the supply of the developer from the plurality of developer supply units to the developing member is blocked by controlling the rotation angle of the rotating body. An image forming apparatus having That.

  The present invention according to claim 2 is the image forming apparatus according to claim 1, wherein the peeling unit peels the developer from the developing member by the control unit controlling a rotation angle of the rotating body. .

  According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect, the collecting unit collects the developer peeled off by the peeling unit by the control unit controlling a rotation angle of the rotating body. Device.

  According to the first aspect of the present invention, developers of different colors can be switched and supplied to the developing member. A system in which a plurality of developer supplies are provided on the rotating body and the developer is supplied to the image holding member is effective from the viewpoint of space and switching time, and the positional relationship between the developer supplying unit and the image holding member is determined. It is advantageous also in reproducing accurately. In the method of fixing the position of the developing member and moving only the developer supply unit as in the present invention, it is necessary to repeat the steps of supplying, blocking, and peeling the developer for each different color, which is particularly effective.

  According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, it is possible to easily prevent color mixing of the developer as compared with the case where the present configuration is not provided. According to the second aspect of the present invention, it is possible to ensure the positional accuracy and reproducibility of the developing member and the developer supplying unit for preventing the developer from reattaching when the developer is peeled off.

  According to the third aspect of the present invention, in addition to the effect of the present invention according to the first or second aspect, the developer can be easily recovered as compared with the case where the present configuration is not provided. According to the third aspect of the present invention, it is possible to ensure the positional accuracy and reproducibility of the developing member and the developer supplying unit for preventing the developer from spilling during the recovery of the developer. If this method is not provided, for example, when a plurality of developer supply units are arranged linearly, the movement distance of each position (development position, separation position, collection position) is set for each of the plurality of developer supply units. However, when a rotating body is used, it can be dealt with only by setting each position angle of one case. In addition, regarding accuracy, when a plurality of developer supply units are linearly arranged, a member for giving accuracy to each of the plurality of developer supply units is necessary. This can be easily realized by arranging the parts with accuracy only for the rotating shaft.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an outline of an image forming apparatus 10 according to an embodiment of the present invention. The image forming apparatus 10 includes an image forming apparatus main body 12, for example, a one-stage sheet feeding unit 14 is disposed on the back side (right side in FIG. 1) of the image forming apparatus main body 12.

  The paper feed unit 14 has a paper feed cassette 16 in which paper is stored. A take-out roll 18 for taking out paper from the paper feed cassette 16 is disposed above the paper feed cassette 16, and a supply roll 20 and a separating roll 22 are disposed in front of the take-out roll 18.

  The supply roll 20 is driven by a drive unit (not shown) and rotates so as to supply a sheet toward a conveyance path 24 described later. The roll 22 is pressed against the supply roll 20 and is rotatable in accordance with the rotation of the supply roll 20, so that the paper is supplied together with the supply roll 20 to a conveyance path 24 described later. Rotate.

  The conveyance path 24 is a sheet path from the supply roll 20 to the discharge port 26, and the conveyance path 24 is located at the upper part of the image forming apparatus main body 12 and is formed substantially horizontally from the paper supply unit 14 to the discharge port 26. ing. A secondary transfer roll 60 and a secondary transfer backup roll 54, which will be described later, are arranged on the upstream side of the fixing device 28 in the conveyance path 24, and the registration roll 30 is located upstream of the secondary transfer roll 60 and the secondary transfer backup roll 54. Is arranged. A discharge roll 32 is disposed in the vicinity of the discharge port 26 of the transport path 24.

  Accordingly, the paper taken out from the paper feeding cassette 16 of the paper feeding unit 14 by the take-out roll 18 is rolled by the supply roll 20 and the separating roll 22, and only the uppermost paper is guided to the transport path 24 and temporarily sent by the registration roll 30. The developer image is transferred between a secondary transfer roll 60 and a secondary transfer backup roll 54, which will be described later, at a timing, and the transferred developer image is fixed by the fixing device 28 and discharged. The paper is discharged from the discharge port 26 by the roll 32.

  In the image forming apparatus main body 12, for example, a developing device 34 is disposed at a substantially central portion. The developing device 34 visualizes an electrostatic latent image held by an image holding body 36 (to be described later) with developers of four colors of yellow, yellow, magenta, cyan, and black.

  In the developing device 34, for example, an image holding member 36 made of a photosensitive member is disposed so as to come into contact with the image forming apparatus 10 from the upper front side. On the back side of the image carrier 36, a charging device 38 made of, for example, a charging roll for uniformly charging the image carrier 36 is provided. That is, a developing bias is applied to the image carrier 36. Further, the image carrier 36 is in contact with an image carrier cleaner 40 on the upstream side of the charging device 38 in the rotation direction of the image carrier 36. For example, the image carrier cleaner 40 scrapes off the developer remaining on the image carrier 36 after the primary transfer.

  Above the developing device 34, an exposure device 42 for writing a latent image on the image carrier 36 charged by the charging device 38 by a light beam such as a laser beam is disposed. Further, an intermediate transfer device 44 is provided on the front side of the image holding member 36 to primarily transfer the developer image visualized by the developing device 34 at the primary transfer position and convey it to a secondary transfer position described later.

  The intermediate transfer device 44 includes, for example, an intermediate transfer member 46 such as an intermediate transfer belt, a primary transfer roll 48, support rolls 50 and 52, a secondary transfer backup roll 54, and tension rolls 56 and 58. The intermediate transfer body 46 is a primary transfer that comes into contact with the image carrier 36 in a lap between a support roll 50 disposed upstream of the primary transfer roll 48 and a support roll 52 disposed downstream of the primary transfer roll 48. The image holding member 36 is wound around the image holding member 36 within a predetermined range, and rotates according to the rotation of the image holding member 36. The tension rolls 56 and 58 apply a predetermined tension to the intermediate transfer member 46. Then, the intermediate transfer member 46 is primarily transferred by the primary transfer roll 48 so that the developer image on the image holding member 36 is superposed in the order of, for example, yellow, magenta, cyan, and black, and the developer image that has been primarily transferred will be described later. It is conveyed toward the secondary transfer roll 60.

  A secondary transfer roll 60 is disposed on the secondary transfer backup roll 54 of the intermediate transfer device 44 with the conveyance path 24 interposed therebetween. That is, the secondary transfer position is between the secondary transfer roll 60 and the secondary transfer backup roll 54, and the secondary transfer roll 60 is primary to the intermediate transfer body 46 with the assistance of the secondary transfer backup roll 54. The transferred developer image is secondarily transferred onto a sheet at the secondary transfer position. Here, the secondary transfer roll 60 is separated from the intermediate transfer body 46 while the intermediate transfer body 46 rotates three times, that is, while the developer images of three colors of yellow, magenta, and cyan are conveyed. When the developer image is transferred, it contacts the intermediate transfer member 46. In addition, a predetermined potential difference is generated between the secondary transfer roll 60 and the secondary transfer backup roll 54. For example, when the secondary transfer roll 60 is set to a high voltage, the secondary transfer backup is performed. The roll 54 is connected to a ground (GND) or the like.

  A fixing device 28 is disposed downstream of the secondary transfer position of the conveyance path 24. The fixing device 28 includes a heating roll and a pressure roll. The fixing device 28 fixes the developer image secondarily transferred to the sheet by the secondary transfer roll 60 and the secondary transfer backup roll 54, and is directed to the discharge roll 32. Transport.

  Further, inside the image forming apparatus 10, a control unit 62 that controls each unit constituting the image forming apparatus 10 is provided.

Next, the developing device 34 will be described in detail.
2 to 4, details of the developing device 34 are shown. The developing device 34 includes a rotating body (conveying unit) 66, a developing roll 68, a layer thickness regulating member 70, a developing roll storage wall 74, a peeling member 76, toner cartridges (supply developer storage units) 78a to 78d, and a developer supply unit. 80a-80d.
Hereinafter, in the case where any one of a plurality of components such as the developer supply units 80a to 80d is not specified, it may be simply abbreviated as “developer supply unit 80” or the like.

The rotator 66 includes toner cartridges 78a to 78d for sequentially supplying yellow, yellow, magenta, cyan, and black developers to the developing roller 68, and developer supplying units 80a to 80a. 80d is detachably provided, and can be rotated counterclockwise (counterclockwise in FIG. 2) around the rotation shaft 82, and the developer supply portions 80a to 80d face the developing roll 68 (development). (Agent supply position). Here, the rotation angle of the rotating body 66 is controlled by, for example, a pulse motor (not shown) controlled by the control unit 62. Further, the rotating body 66 may be positioned by a ratchet or the like.
The developer accommodated in the developer supply units 80a to 80d is, for example, a two-component developer having a nonmagnetic toner and a magnetic carrier.

  As shown in FIG. 3, the toner cartridge 78 includes an unused toner storage portion 84 that stores unused toner, and a developer recovery that recovers the developer from which the release member 76 has been separated (collected) from the developing roll 68. Part 86. The unused toner storage unit 84 is provided with a supply port 87 for supplying unused toner to the developer supply unit 80. The developer collecting unit 86 includes an opening 88 for collecting the developer peeled off by the peeling member 76, an opening / closing member 90 for opening and closing the opening 88, and discharging the collected developer to the developer supplying unit 80. A (supply) discharge port 92 is provided.

As shown in FIG. 4, the developer supply unit 80 includes a feeder main body 94, a first agitation transport member 96, and a second agitation transport member 98. The supply body 94 includes a first receiving port 100 that receives toner from the toner cartridge 78, a second receiving port 102 that receives the developer collected by the developer collecting unit 86, and an opening that supplies the developer to the developing roll 68. A section 104 is provided. The first agitation and conveyance member 96 conveys the toner supplied from the toner cartridge 78 and the developer received from the developer recovery unit 86 toward the second agitation and conveyance member 98 while agitating. The second agitating and conveying member 98 agitates the developer and conveys the developer toward the developing roll 68 when the opening 104 moves to a position facing the developing roll 68 by the rotation of the rotating body 66. And supply. That is, the developer collected by the developer collecting unit 86 is reused as the developer supplied to the developing roll 68.
The developer is conveyed so as to circulate in the feeder main body 94 while being agitated by the first agitating / conveying member 96 and the second agitating / conveying member 98 so that the nonmagnetic toner adheres around the magnetic carrier. Has been.

  The developing roll 68 (FIG. 2) includes a magnet 110 that is fixed with a plurality of north and south poles extending in the axial direction, and rotates while accommodating the magnet 110 in accordance with the magnetic force of the magnet 110. And a sleeve 112 that conveys the developer in the circumferential direction. The magnet 110 is disposed opposite to the image carrier 36 and supplies a magnetic pole (development pole) that supplies the developer on the developing roll 68 to the image carrier 36, and a magnetic pole (at which the developer is supplied from the developer supply unit 80) Pickup poles) are arranged on the upper side of the developer supply unit 80 and the like, and magnetic poles (pickoff poles) for repelling the developer are arranged on the lower side of the developer supply unit 80 and the like. The developing roll 68 is accommodated in a developing roll accommodating wall 74 that is opened so that a portion facing the image holding body 36 is exposed, and a predetermined gap is formed between the developing roll 68 and the image holding body 36. The developer of each color held by the magnetic force is supplied to the image carrier 36.

  The layer thickness regulating member 70 regulates the layer thickness of the developer attached to the surface of the developing roll 68 (held by the developing roll 68). The developing roll housing wall 74 is formed with a guide portion 118 that guides the developer to the developer supply portion 80.

  The peeling member 76 includes a rotating shaft 114 provided substantially parallel to the developing roll 68, and a rare earth such as a rare earth that rotates clockwise (clockwise in FIG. 2) around the rotating shaft 114 under the control of the control unit 62. The developer remaining after the developing roll 68 is supplied to the image carrier 36 is peeled off from the developing roll 68 by a magnetic force, and the developer is supplied to the developer supplying section 80 via the guide section 118 described above. Lead to.

  FIG. 5 is an enlarged view showing a state where the magnet 116 peels off the developer remaining on the developing roll 68 (including the developer around the peeling position). As shown in FIG. 5A, when the peeling member 76 disposed below the developing roll 68 via the developing roll accommodating wall 74 rotates and the magnet 116 approaches the developing roll 68, the magnet 116 becomes the developer. Is attracted to the guide 118 side. Further, as shown in FIG. 5B, when the peeling member 76 rotates and the magnet 116 starts to be separated from the developing roll 68, the developer is peeled from the developing roll 68 by the magnetic force of the magnet 116. Further, as shown in FIG. 5C, when the peeling member 76 further rotates and the magnet 116 further moves away from the developing roll 68, the developer is attracted by the magnetic force of the magnet 116 and is lowered along the guide portion 118. And fall further downward in the region where the magnetic force does not reach. Here, the guide portion 118 is a partition wall that separates the peeling member 76 and the developer, and the distance to the developing roll 68 and the magnet 116 increases as the magnet 116 moves away from the position approaching the developing roll 68. It is formed to have.

As described above, when the peeling member 76 peels off the developer, the magnet 116 moves toward the developing roll 68 so that the magnetic force of the magnet 116 acts on the developer held by the developing roll 68. After the member 76 peels off the developer, the magnet 116 rotates and moves away from the developing roll 68 (clockwise in FIG. 5) so as to isolate the peeled developer from the developing roll 68.
When the developing device 34 visualizes the electrostatic latent image, the control unit 62 determines the position where the magnetic force of the magnet 116 decreases with respect to the developer held by the developing roll 68 (the opposite side of the developing roll 68). ) To stop the magnet 116. Then, the control unit 62 rotates and rotates the magnet 116 so that the magnetic force of the magnet 116 acts on the developer held by the developing roll 68 after blocking the supply of the developer by rotating the rotating body 66.

Next, an operation example of the developing device 34 will be described.
FIG. 6 shows an outline of an operation example of the developing device 34. As shown in FIG. 6A, when the developing device 34 visualizes the electrostatic latent image with, for example, a magenta developer, the developing roll 68 is supplied from a developer supply unit 80b located at the developer supply position. Holds magenta developer and rotates.

  When the visualization with the magenta developer is completed, the developing device 34 rotates the rotating member 66 (less than 90 °) by the control of the control unit 62 as shown in FIG. 3) and the developer supply unit 80b moves out of the range in which the magnetic force of the developer supply magnetic pole of the developing roll 68 acts to supply the magenta developer from the developer supply unit 80b to the developing roll 68. And is stopped in a state where the opening 88 is positioned so as to cover the space between the developing roll 68 and the guide 118. That is, a collection path for collecting the developer peeled from the developing roll 68 is formed.

  When the opening 88 stops between the developing roll 68 and the guide 118, the developing device 34 rotates the peeling member 76 under the control of the control section 62 as shown in FIG. The magenta developer held by is peeled off.

  As shown in FIG. 6D, the magenta developer peeled from the developing roll 68 is guided to the developer collecting portion 86 by the guide portion 118 as the magnet 116 moves away from the guide portion 118.

  As shown in FIG. 6E, when the magnet 116 further rotates, the magenta developer peeled from the developing roll 68 is collected (temporarily) in the developer collecting unit 86.

When the magenta developer peeled from the developing roll 68 is collected, as shown in FIG. 6F, the developing device 34 supplies the developer to visualize the electrostatic latent image with the cyan developer. The rotating body 66 rotates so that the portion 80c faces the developing roll 68. Here, the developing roller 68 rotates while holding the cyan developer supplied from the developer supply unit 80c.
On the other hand, in the toner cartridge 78b, the opening / closing member 90 (see FIG. 3) is closed, and the recovered magenta developer is still stored in the developer recovery portion 86.

During color printing, the developing device 34 visualizes the electrostatic latent image with a yellow developer, then visualizes the electrostatic latent image with a magenta and cyan developer as described above, and then statically develops with a black developer. The electric latent image is visualized.
In the developing device 34, when the electrostatic latent image is visualized again with the magenta developer, the rotating body 66 rotates so that the developer supply unit 80b faces the developing roll 68 under the control of the control unit 62. Here, the inclination of the developer recovery unit 86 with respect to the direction of gravity changes as the rotating body 66 rotates. As shown in FIG. 6G, when the rotation of the rotating body 66 changes the inclination of the developer recovery section 86 with respect to the direction of gravity so that the discharge port 92 (see FIG. 3) is positioned below, the developer recovery section. The magenta developer collected in 86 is supplied to the developer supply unit 80b (the magenta developer is returned to the developer supply unit 80b by its own weight).

Next, the operation of the embodiment of the present invention will be described.
When the image forming signal is sent, the image carrier 36 is uniformly charged by the charging device 38, and light is emitted from the exposure device 42 to the charged image carrier 36 based on the image signal. The light beam from the exposure device 42 exposes the surface of the image carrier 36 to form an electrostatic latent image.

The electrostatic latent image held on the image holding body 36 is developed by the developing device 34 for each color of the developer, and is primarily transferred to the intermediate transfer body 46. Then, the developer images of the respective colors are superimposed on the intermediate transfer body 46 to form a color image.
Here, yellow, magenta, cyan, and black developers are respectively supplied to the developing roll 68 from the developer supply units 80a to 80d. The developer supplied excessively to the developing roll 68 is collected in the developer supplying section 80 of the same color before the next color developer is supplied to the developing roll 68. In the primary transfer, the waste developer remaining on the image carrier 36 is scraped off and collected by the image carrier cleaner 40.

  On the other hand, the paper stored in the paper feed cassette 16 is taken out by the take-out roll 18 by a paper feed signal or the like, and is fed by the supply roll 20 and the separating roll 22, and only the uppermost paper is guided to the transport path 24, and the registration The roller 30 is temporarily stopped by the roll 30 and is guided between the secondary transfer roll 60 and the secondary transfer backup roll 54 with timing. When the sheet is guided between the secondary transfer roll 60 and the secondary transfer backup roll 54, the developer image primarily transferred to the intermediate transfer body 46 is transferred by the secondary transfer roll 60 and the secondary transfer backup roll 54. Secondary transferred onto paper.

  The sheet onto which the developer image has been transferred is guided to the fixing device 28, and the developer image is fixed by a heating roll and a pressure roll. The sheet on which the developer image is fixed is discharged from the discharge port 26 by the discharge roll 32.

Next, a first modification of the developing device 34 will be described.
FIG. 7 is a side view showing a first modification of the developing device 34. Note that, in the first modification of the developing device 34, the same reference numerals are given to substantially the same parts as those constituting the developing device 34 shown in FIG.
As shown in FIG. 7, the developer supply unit 80 is provided with an opening / closing member 300 for preventing the developer from flowing out, and a scraping member 302 for scraping off the developer remaining on the developing roll 68. .

FIG. 8 is a schematic diagram illustrating an operation example of the first modification of the developing device 34. As shown in FIG. 8A, when the developing device 34 visualizes the electrostatic latent image with, for example, a magenta developer, the developing roll 68 is supplied from the developer supply unit 80b located at the developer supply position. Holds magenta developer and rotates.
Here, the distance between the surface of the developing roll 68 and the shaft surface of the second stirring / conveying member 98 is, for example, about 6.5 mm.

When the visualization with the magenta developer is completed, the developing device 34 opens and closes the developer supply unit 80b by rotating the rotating body 66 by 20 degrees under the control of the control unit 62 as shown in FIG. 8B. As the member 300 moves, the scraping member 302 comes into contact with the surface of the developing roll 68 and scrapes off the developer remaining on the developing roll 68. The developer scraped off by the scraping member 302 is collected in the feeder main body 94 at a position different from the developer supply position.
Here, the distance between the surface of the developing roll 68 and the shaft surface of the second agitating / conveying member 98 is increased to, for example, about 11 mm, and the developer is supplied from the developer supplying unit 80 to the developing roll 68. Blocked.

  When the magenta developer peeled from the developing roll 68 is collected, as shown in FIG. 8C, the developing device 34 supplies the developer so as to visualize the electrostatic latent image with the cyan developer. The rotating body 66 rotates 70 degrees so that the portion 80 c faces the developing roll 68. Here, the developing roller 68 rotates while holding the cyan developer supplied from the developer supply unit 80c.

Next, a second modification of the developing device 34 will be described.
FIG. 9 is a side view showing a second modification of the developing device 34. Note that in the second modification of the developing device 34, the same reference numerals are given to substantially the same parts as the developing device 34 shown in FIG.
As shown in FIG. 9, the developer supply unit 80 is provided with an opening / closing member 300 for preventing the developer from flowing out. Further, for example, the rotating body 66 is provided with a scraping member 304 that scrapes (peels) the developer remaining on the developing roll 68.

FIG. 10 is a schematic diagram illustrating an operation example of the second modification of the developing device 34. As shown in FIG. 10A, when the developing device 34 visualizes the electrostatic latent image with, for example, a magenta developer, the developing roll 68 is supplied from a developer supply unit 80b located at the developer supply position. Holds magenta developer and rotates.
Here, the distance between the surface of the developing roll 68 and the shaft surface of the second stirring / conveying member 98 is, for example, about 6.5 mm.

When the visualization with the magenta developer is completed, the developing device 34, as shown in FIG. 10B, is controlled by the control unit 62 so that the rotating body 66 rotates, for example, 53 degrees, so that the developer supply unit 80b While the opening / closing member 300 is closed, the scraping member 304 comes into contact with the surface of the developing roll 68 and scrapes off the developer remaining on the developing roll 68. The developer scraped off by the scraping member 304 is collected by the toner cartridge 78 at a position different from the developer supply position.
Here, the distance between the surface of the developing roll 68 and the shaft surface of the second stirring / conveying member 98 is increased to, for example, about 20 mm, and the developer is supplied from the developer supplying unit 80 to the developing roll 68. Blocked.

  When the magenta developer peeled from the developing roll 68 is collected, as shown in FIG. 10C, the developing device 34 supplies the developer so as to visualize the electrostatic latent image with the cyan developer. The rotating body 66 rotates 37 degrees so that the portion 80 c faces the developing roll 68. Here, the developing roller 68 rotates while holding the cyan developer supplied from the developer supply unit 80c.

1 is a side view illustrating an outline of an image forming apparatus according to an embodiment of the present invention. It is a side view which shows the Example of a developing device. FIG. 3 is a side view showing details of the toner cartridge. FIG. 4 is a side view showing details of a developer supply unit. FIG. 6 is an enlarged view showing a state where a magnet peels off developer (including developer around a peeling position) remaining on a developing roll. It is the schematic which shows the operation example of a developing device. It is a side view which shows the 1st modification of a developing device. It is a schematic diagram showing an example of operation of the 1st modification of a development device. It is a side view which shows the 2nd modification of a developing device. It is the schematic which shows the operation example of the 2nd modification of a developing device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 14 Paper supply unit 24 Conveying path 28 Fixing apparatus 34 Developing apparatus 36 Image holding body 38 Charging apparatus 42 Exposure apparatus 44 Intermediate transfer apparatus 54 Secondary transfer backup roll 60 Secondary transfer roll 62 Control part 66 Rotating body 68 Development Roll 70 Layer thickness regulating member 72 Block member 74 Developing roll housing wall 76 Separating members 78a to 78d Toner cartridges 80a to 80d Developer supply unit 82 Rotating shaft 84 Container body 86 Developer collecting unit 88 Opening 90 Opening and closing member 92 Discharge port 94 Container body 96 First stirring / conveying member 98 Second stirring / conveying member 100 First receiving port 102 Second receiving port 104 Opening portion 110 Magnet 112 Sleeve 114 Rotating shaft 116 Magnet 118 Guide portion 300 Opening / closing member 302 Scraping Scraping member 304 scraping member

Claims (3)

An image carrier,
A developing member that includes a magnet and supplies a developer held by the magnetic force of the magnet to the image carrier;
A plurality of developer supply units that individually supply different color developers to the developing member according to the magnetic force of the magnet;
A rotating body that is provided with the plurality of developer supply sections and rotates about a rotation axis;
Peeling means for peeling off the developer remaining after the developing member supplied to the image carrier from the developing member;
A collecting means for collecting the developer peeled off by the peeling means;
The rotation angle of the rotating body is defined by a state in which the plurality of developer supply units supply developer to the developing member and a state in which supply of the developer from the plurality of developer supply units to the developing member is blocked. An image forming apparatus comprising: a control unit that switches each by controlling. The peeling means includes
The image forming apparatus according to claim 1, wherein the control unit controls the rotation angle of the rotating body to separate the developer from the developing member. The recovery means includes
The image forming apparatus according to claim 1, wherein the control unit controls a rotation angle of the rotating body to collect the developer separated by the peeling unit.

Images