JP2007279235A - Charging device, cartridge, image forming apparatus, and image forming system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To properly transmit drive force from a third gear to a first gear, by receiving the drive force from the first gear for rotating a charging roller and a second gear provided on an image carrier in order to rotate the image carrier, and stabilizing an interval with the third gear for transmitting the drive force to the first gear. <P>SOLUTION: The charging device comprises the charging roller for charging the image carrier for carrying latent images; the first gear for rotating the charging roller; the third gear for transmitting the drive force to the first gear; by receiving the drive force from the second gear provided on the image carrier, in order to rotate the image carrier; a pushing lever, capable of being rotated about a center shaft of the third gear, in order to push the electrifying roller to an image carrier side, by supporting the charging roller and the shaft of the first gear; and a biasing member for biasing the push lever. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a charging device, a cartridge, an image forming apparatus, and an image forming system.

  Image forming apparatuses such as laser beam printers are already well known. When the image forming apparatus receives an image signal or the like from an external device such as a host computer, the image forming apparatus forms a latent image on the image carrier and develops the latent image with the developer in the developing device to develop the developer image. Then, the developer image is transferred to a medium, the developer image is fixed to the medium, and finally an image is formed on the medium.

In addition, the image forming apparatus includes, as an apparatus for charging the image carrier, for example, a charging roller for charging an image carrier for carrying a latent image, and a first roller for rotating the charging roller. A third gear for receiving a driving force from a gear and a second gear provided on the image carrier for rotating the image carrier, and transmitting the driving force to the first gear; A pressing lever that supports the charging roller and the shaft of the first gear and is rotatable to press the charging roller toward the image bearing member; and an urging member for urging the pressing lever. It is conceivable to have a charging device provided.
JP 2000-361916 A

  By the way, in order to appropriately charge the image carrier, the interval between the image carrier and the charging roller must be stabilized. That is, when the image carrier rotates, the image carrier is shaken. Therefore, it is necessary to adjust the position of the charging roller according to the shake. Here, when the charging device is used, the pressing lever that supports the charging roller can be rotated according to the shake of the image carrier while being urged by the urging member. As a result, the charging roller is pressed toward the image carrier so that the distance between the charging roller and the image carrier is maintained, and the position of the charging roller is adjusted.

  However, for example, when the distance between the first gear and the third gear changes as the pressing lever rotates, the driving force is appropriately transmitted from the third gear to the first gear. There is a risk of disappearing.

  The present invention has been made in view of such a problem, and an object thereof is to stabilize the distance between the first gear and the third gear and to appropriately drive the third gear to the first gear. It is in transmitting power.

  In order to solve the above-mentioned problems, the main present invention is to provide a charging roller for charging an image carrier for carrying a latent image, a first gear for rotating the charging roller, and the image carrier. A third gear for receiving a driving force from a second gear provided on the image carrier for rotating the image carrier and transmitting the driving force to the first gear; the charging roller; and the first gear. A pressing lever that is rotatable about a central axis of the third gear to press the charging roller toward the image carrier, and a biasing member for biasing the pressing lever A charging device comprising:

  Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

  At least the following will be made clear by the description of the present specification and the accompanying drawings.

A charging roller for charging an image carrier for carrying a latent image, a first gear for rotating the charging roller, and an image carrier provided for rotating the image carrier. A third gear for receiving a driving force from the second gear and transmitting the driving force to the first gear, the charging roller and the shaft of the first gear are supported, and the charging roller is A charging device comprising: a pressing lever that is rotatable around a central axis of the third gear for pressing toward the carrier; and a biasing member for biasing the pressing lever.
According to such a charging device, it is possible to stably transmit the driving force from the third gear to the first gear by stabilizing the interval between the first gear and the third gear.

The pressing lever may support a cleaning roller that contacts the peripheral surface of the charging roller to remove dirt on the peripheral surface.
In this case, since the cleaning roller and the charging roller are supported by the same member, the distance between the shafts of the charging roller and the cleaning roller is stabilized. Furthermore, even when the charging roller is bent due to the contact of the cleaning roller, the contact force exerted on the charging roller by the cleaning roller is difficult to change, and thus the fluctuation in the amount of bending of the charging roller due to the contact force is suppressed. Is done. Thereby, the interval between the charging roller and the image carrier can be stabilized.

The shaft of the first gear is a rotating shaft of the cleaning roller, and the first gear rotates the cleaning roller while the cleaning roller is in contact with the charging roller, and the charging roller The charging roller may be rotated by friction between the cleaning roller and the cleaning roller.
In such a case, it is not necessary to separately provide a gear for rotating the charging roller in addition to the gear for rotating the cleaning roller.

The first gear may be provided on the charging roller.
In such a case, the driving force can be appropriately transmitted to the charging roller.

Further, the charging roller has a large-diameter portion having a diameter larger than the rotation shaft of the charging roller, a diameter larger than the large-diameter portion, and abuts on a peripheral surface of the image carrier, and the image carrier and the A gap forming portion for forming a gap with the large diameter portion, and charging the image carrier in a state where the large diameter portion and the image carrier are not in contact with each other. Good.
In such a case, since the large diameter portion of the charging roller charges the image carrier without contacting the image carrier, for example, deposits such as developer adhering to the surface of the image carrier are applied to the charging roller. The image carrier can be appropriately charged due to the effect of suppressing the transfer of light.

A charging roller for charging an image carrier for carrying a latent image; a first gear for rotating the charging roller; and an image carrier for rotating the image carrier. A second gear for receiving a driving force from the second gear and transmitting the driving force to the first gear; supporting the charging roller and the shaft of the first gear; A pressing lever capable of rotating around a central axis of the third gear for pressing toward the image carrier, and a biasing member for biasing the pressing lever, wherein the shaft of the first gear is The rotating shaft of the cleaning roller, and the first gear rotates the cleaning roller in a state where the cleaning roller is in contact with the charging roller, and friction between the charging roller and the cleaning roller. The charging battery The charging roller has a large-diameter portion having a diameter larger than the rotation shaft of the charging roller and a diameter larger than the large-diameter portion, and is in contact with the peripheral surface of the image carrier to support the image carrier. A gap forming portion for forming a gap between the body and the large diameter portion, and charging the image carrier in a state where the large diameter portion and the image carrier are not in contact with each other A charging device.
According to such a charging device, the effects of the present invention can be achieved more effectively because most of the effects described above can be achieved.

An image carrier for carrying a latent image; a second gear provided on the image carrier for rotating the image carrier; a charging roller for charging the image carrier; A first gear for rotating the charging roller; a third gear for receiving the driving force from the second gear and transmitting the driving force to the first gear; the charging roller and the first gear; A pressing lever that is rotatable about a central axis of the third gear to press the charging roller toward the image carrier, and a biasing member for biasing the pressing lever It is also possible to realize a cartridge characterized by having a charging device including
According to such a cartridge, it becomes possible to stabilize the distance between the first gear and the third gear and to appropriately transmit the driving force from the third gear to the first gear.

Further, in the cartridge, a housing for housing the image carrier and the charging device is provided, and the housing includes a rotation shaft of the image carrier on which the second gear is provided. The shaft of the third gear may be supported.
In such a case, since the rotation shaft of the image carrier and the shaft of the third gear are positioned by the same member, a tolerance can be reduced with respect to the distance between both shafts. The tolerance of the distance with the third gear can be reduced. As a result, since the distance between the first gear and the third gear and the distance between the second gear and the third gear are stabilized, a driving force is appropriately applied from the second gear to the first gear. It is possible to communicate.

An image carrier for carrying a latent image; a second gear provided on the image carrier for rotating the image carrier; a charging roller for charging the image carrier; A first gear for rotating the charging roller; a third gear for receiving the driving force from the second gear and transmitting the driving force to the first gear; the charging roller and the first gear; A pressing lever that is rotatable about a central axis of the third gear to press the charging roller toward the image carrier, and a biasing member for biasing the pressing lever In addition, an image forming apparatus characterized in that a charging device including a charging device and a cartridge having the charging device is provided.
According to such an image forming apparatus, it is possible to stably transmit the driving force from the third gear to the first gear by stabilizing the distance between the first gear and the third gear.

Also, a computer and an image forming apparatus connectable to the computer, an image carrier for carrying a latent image, a second gear provided for rotating the image carrier, and the image A charging roller for charging the carrier, a first gear for rotating the charging roller, and a second gear for receiving the driving force from the second gear and transmitting the driving force to the first gear. A pressing lever that supports the three gears, the charging roller and the shaft of the first gear, and is rotatable around the central axis of the third gear to press the charging roller toward the image carrier; An image forming system including an image forming apparatus provided with a cartridge including a charging device including a biasing member for biasing the pressing lever can be realized.
According to such an image forming system, it is possible to stably transmit the driving force from the third gear to the first gear by stabilizing the distance between the first gear and the third gear.

=== Overview of Image Forming Apparatus ===
Next, a configuration example and an operation example will be described using a laser beam printer (hereinafter also referred to as a printer) 10 as an example of the “image forming apparatus” with reference to FIGS. 1 and 2. FIG. 1 is a diagram illustrating main components constituting the printer 10. FIG. 2 is a block diagram illustrating the configuration of the control unit 100 of the printer 10. In FIG. 1, the vertical direction is indicated by arrows. For example, the paper feed tray 92 is disposed at the lower part of the printer 10, and the fixing unit 90 is disposed at the upper part of the printer 10.

  The printer 10 according to the present embodiment primarily transfers a toner image as an example of a developer image to an intermediate transfer belt 70 that is an intermediate transfer medium, and then transfers the toner image to a medium (paper, film, cloth, etc.). This is an apparatus for forming an image on the medium by performing secondary transfer and fixing the toner image. As shown in FIG. 1, the printer 10 includes a process cartridge 15Y as an example of a “cartridge” for forming a toner image along the rotation direction of the intermediate transfer belt 70 (the arrow direction shown in FIG. 1). 15M, 15C, 15K, exposure units 40Y, 40M, 40C, 40K, intermediate transfer belt 70, primary transfer units 60Y, 60M, 60C, 60K, secondary transfer unit 80, intermediate transfer belt cleaning unit 85, and The image forming apparatus includes a fixing unit 90, a display unit 95 that serves as a notification unit for a user and is a liquid crystal panel, and a control unit 100 that controls these units and operates as a printer.

  The process cartridges 15Y, 15M, 15C, and 15K have a function of containing toner T as an example of a developer and forming the toner image using the toner T. The process cartridges 15Y, 15M, 15C, and 15K are provided corresponding to each color of yellow (Y), magenta (M), cyan (C), and black (K). That is, the process cartridge 15Y contains yellow (Y) toner, the process cartridge 15M contains magenta (M) toner, the process cartridge 15C contains cyan (C) toner, and the process cartridge 15K contains black (K) toner. Thus, a single color toner image of each color is formed. The four process cartridges 15Y, 15M, 15C, and 15K are each a photoreceptor unit provided with photoreceptors 210Y, 210M, 210C, and 210K as an example of an “image carrier” for carrying a latent image. 200Y, 200M, 200C, and 200K, and developing units 50Y, 50M, 50C, and 50K that contain toner T and develop the latent image as a toner image using the toner T. The four process cartridges 15Y, 15M, 15C, and 15K are arranged in a row in the horizontal direction along the rotational direction of the intermediate transfer belt 70, as shown in FIG. The holding unit is detachably attached to the main body of the printer 10.

  In the photoreceptor units 200Y, 200M, 200C, and 200K, the photoreceptors 210Y, 210M, 210C, and 210K are rotatably supported. The photoconductors 210Y, 210M, 210C, and 210K are charged in the photoconductor units 200K, 200M, 200C, and 200K while rotating. The photoconductors 210Y, 210M, 40C, and 40K are charged by the exposure units 40Y, 40M, 40C, and 40K, which will be described later. The latent images formed on 210M, 210C, and 210K are carried. The details of the photoconductor units 200Y, 200M, 200C, and 200K will be described in the section “Configuration Example of Photoconductor Unit” described later.

  On the other hand, the developing units 50Y, 50M, 50C, and 50K respectively include toner storage portions 51Y, 51M, 51C, and 51K for storing the toner T, and developing rollers 52Y, 52M, 52C, and the like. 52K and supply rollers 53Y, 53M, 53C, 53K for supplying the toner T stored in the toner storage portions 51Y, 51M, 51C, 51K to the developing rollers 52Y, 52M, 52C, 52K. is doing. The developing rollers 52Y, 52M, 52C, and 52K are opposed to the photoreceptors 210Y, 210M, 210C, and 210K at a predetermined interval, respectively, and using the toner T, the photoreceptors 210Y, 210M, It has a function of developing latent images carried on 210C and 210K.

  The exposure units 40Y, 40M, 40C, and 40K are devices that form a latent image by irradiating the photoconductors 210Y, 210M, 210C, and 210K with a laser. As shown in FIG. 1, the exposure units 40Y, 40M, 40C, and 40K are provided for the photoreceptors 210Y, 210M, 210C, and 210K, respectively. For example, the exposure unit 40Y irradiates the photoconductor 210Y of the process cartridge 15Y with a laser. The exposure units 40Y, 40M, 40C, and 40K include a semiconductor laser, a polygon mirror, an F-θ lens, and the like, and a laser that is modulated based on an image signal input from a host computer (not shown). Irradiate the charged photoreceptors 210Y, 210M, 210C, and 210K.

  The intermediate transfer belt 70 is a device for rotating and moving the toner images while carrying the toner images on the photoreceptors 210Y, 210M, 210C, and 210K. The intermediate transfer belt 70 is an endless belt, and is driven to rotate at substantially the same peripheral speed as the photoconductors 210Y, 210M, 210C, and 210K.

  The primary transfer units 60Y, 60M, 60C, and 60K are devices for transferring the toner images formed on the photoreceptors 210Y, 210M, 210C, and 210K to the intermediate transfer belt 70. The primary transfer units 60Y, 60M, 60C, and 60K are provided for each of the photoreceptors 210Y, 210M, 210C, and 210K, similarly to the exposure units 40Y, 40M, 40C, and 40K. The primary transfer units 60Y, 60M, 60C, and 60K are in contact with the intermediate transfer belt 70 at the first contact portion T1, respectively. The toner images formed on the photoconductors 210Y, 210M, 210C, and 210K at the first contact portions T1 are transferred to the intermediate transfer belt 70. As a result, the four color toner images are sequentially superimposed on the intermediate transfer belt 70 to form a full color toner image.

  The secondary transfer unit 80 is a device for transferring a single color toner image or a full color toner image formed on the intermediate transfer belt 70 to the medium. The secondary transfer unit 80 transfers the toner image on the intermediate transfer belt 70 to the medium at the second contact portion T2 where the secondary transfer unit 80 contacts the intermediate transfer belt 70.

The fixing unit 90 is a device for heating and pressurizing a single-color toner image or a full-color toner image transferred onto a medium and fusing it to the medium to form a permanent image.

  The intermediate transfer belt cleaning unit 85 includes a rubber intermediate transfer belt cleaning blade 87 that is in contact with the surface of the intermediate transfer belt 70. For example, the toner image is secondarily transferred onto the medium by the secondary transfer unit 80. After that, the toner T remaining on the intermediate transfer belt 70 is scraped off by the intermediate transfer belt cleaning blade 87.

  As shown in FIG. 2, the control unit 100 includes a main controller 101 and a unit controller 102. An image signal and a control signal are input to the main controller 101, and in response to a command based on the image signal and the control signal. A unit controller 102 controls each of the units and forms an image.

  Next, a color image forming operation of the printer 10 configured as described above will be described.

  First, when an image signal and a control signal from a host computer (not shown) are input to the main controller 101 of the printer 10 via the interface (I / F) 112, the unit controller 102 based on a command from the main controller 101. By the control, the photoreceptors 210Y, 210M, 210C, 210K, the intermediate transfer belt 70, and the like rotate. The photoconductors 210Y, 210M, 210C, and 210K are sequentially charged by charging devices 300Y, 300M, 300C, and 300K described later at the charging position while rotating inside the photoconductor units 200Y, 200M, 200C, and 200K.

  The charged areas of the photoconductors 210Y, 210M, 210C, and 210K reach the exposure position as the photoconductors 210Y, 210M, 210C, and 210K rotate, and the exposure units 40Y, 40M, 40C, and 40K perform yellow ( A latent image corresponding to image information of Y), magenta (M), cyan (C), and black (K) is formed in the region. Then, the latent image is moved with the rotation of the photoconductors 210Y, 210M, 210C, and 210K while being held on the photoconductors 210Y, 210M, 210C, and 210K.

  The latent images carried on the photoreceptors 210Y, 210M, 210C, and 210K are carried on the developing rollers 52Y, 52M, 52C, and 52K when they reach the development position by the rotation of the photoreceptors 210Y, 210M, 210C, and 210K, respectively. The toner T is developed. As a result, monochromatic toner images are formed on the photoreceptors 210Y, 210M, 210C, and 210K. In developing, a developing bias is applied to the developing rollers 52Y, 52M, 52C, and 52K.

  Each single-color toner image formed on the photoreceptors 210Y, 210M, 210C, and 210K reaches the first contact portion T1 as the photoreceptors 210Y, 210M, 210C, and 210K rotate, and the primary transfer unit 60Y. , 60M, 60C, and 60K, primary transfer is performed on the intermediate transfer belt 70. That is, each time a region to which the toner image on the intermediate transfer belt 70 is transferred by driving the intermediate transfer belt 70 passes through each first contact portion T1, it is formed on the photoreceptors 210Y, 210M, 210C, and 210K. The four-color single-color toner images are sequentially primary-transferred to the area where the toner images are transferred. Thereby, the four color toner images are overlapped to form a full color toner image. Further, when each toner image is primarily transferred, a primary transfer bias having a polarity opposite to the charging characteristics of the toner T is applied to the primary transfer units 60Y, 60M, 60C, and 60K. During this time, the photoreceptors 210 </ b> Y, 210 </ b> M, 210 </ b> C, and 210 </ b> K are in contact with the intermediate transfer belt 70, while the secondary transfer unit 80 is separated from the intermediate transfer belt 70.

  The full-color toner image formed on the intermediate transfer belt 70 reaches the second contact portion T2 as the intermediate transfer belt 70 rotates, and is secondarily transferred to the medium by the secondary transfer unit 80. The medium is conveyed from the paper feed tray 92 to the second contact portion T2 via the paper feed roller 94 and the registration roller 96. Further, when performing the secondary transfer operation, the secondary transfer unit 80 is pressed against the intermediate transfer belt 70, and a secondary transfer bias is applied to the secondary transfer unit 80.

  When the medium on which the full-color toner image is secondarily transferred is conveyed to the fixing unit 90, the full-color toner image is heated and pressurized and fused to the medium. Thereafter, the medium on which the image is formed is conveyed to the paper discharge tray 98 via the paper discharge roller 97.

  After the full-color toner image is secondarily transferred, the toner T remaining on the intermediate transfer belt 70 is transferred to the intermediate transfer belt 70 and the intermediate transfer belt cleaning blade 87 as the intermediate transfer belt 70 rotates. And is scraped off by the intermediate transfer belt cleaning blade 87.

=== Overview of Control Unit ===
Next, the configuration of the control unit 100 will be described with reference to FIG. The main controller 101 of the control unit 100 is connected to a host computer via an interface 112 and includes an image memory 113 for storing image signals input from the host computer.

  The unit controller 102 is electrically connected to each unit of the printer 10 main body, receives signals from sensors included in the unit controller 102, detects the state of each unit, and based on signals input from the main controller 101. To control each unit.

=== Configuration Example of Photosensitive Member Unit ===
Next, configuration examples of the photoconductor units 200Y, 200M, 200C, and 200K will be described with reference to FIGS. FIG. 3 is a perspective view of the photoreceptor unit 200Y. FIG. 4 is a schematic diagram showing the appearance of the photoreceptor 210Y, the charging roller 310Y, the cleaning roller 320Y, and the photoreceptor cleaning unit 220Y attached to the photoreceptor unit 200Y. FIG. 5 is a configuration diagram of the photoreceptor unit 200Y, and is a view of the arrangement of the photoreceptor 210Y, the charging device 300Y, and the like as viewed from above. FIG. 6 is a schematic cross-sectional view of the photoconductor unit 200Y, and is a view showing main components in the II cross section of FIG. 3, 4, and 6, the vertical direction of the photoconductor unit 200 </ b> Y is indicated by arrows. In FIGS. 3 to 5, the longitudinal direction of the photoconductor unit 200Y is indicated by an arrow.

  As described above, the photosensitive units 200Y, 200M, 200C, and 200K are elements that constitute the process cartridges 15Y, 15M, 15C, and 15K together with the developing units 50Y, 50M, 50C, and 50K. The photoconductor units 200Y, 200M, 200C, and 200K include photoconductors 210Y, 210M, 210C, and 210K, charging devices 300Y, 300M, 300C, and 300K, photoconductor cleaning units 220Y, 220M, and 220C as main components. 220K, and photoreceptor unit frames 230Y, 230M, 230C, and 230K as examples of a “housing” that accommodates these devices.

  In the present embodiment, the four process cartridges 15Y, 15M, 15C, and 15K have the same configuration. Therefore, the photosensitive units 200Y, 200M, 200C, and 200K and the constituent elements of the photosensitive units 200Y, 200M, 200C, and 200K are the same as each other, and a yellow toner image is formed in the following description. The photosensitive unit 200Y included in the process cartridge 15Y will be described as an example.

  The photoreceptor 210Y is a drum-like device that forms a latent image on its outer peripheral surface and carries the latent image. This photoreceptor 210Y has an aluminum cylindrical base material and a photosensitive layer formed on the outer peripheral surface thereof for forming the latent image. Further, flanges 211Y are provided at both ends in the axial direction. Have. As shown in FIG. 3, the photoreceptor 210Y is attached to the photoreceptor unit 200Y with a part of the peripheral surface of the photoreceptor 210Y exposed. Further, the photoreceptor 210Y is rotatably supported by the rotation shaft 212Y, and in the present embodiment, rotates around the rotation shaft 212Y in the direction of the arrow shown in FIG. As shown in FIG. 5, the rotation shaft 212Y is supported by a shaft support portion 231Y of a photoreceptor unit frame 230Y described later. The rotating shaft 321Y passes through the shaft support portion 231Y of the photoconductor unit frame 230Y on one end side in the axial direction of the photoconductor 210Y (that is, the longitudinal direction of the photoconductor unit 200Y).

  The charging device 300Y is a device for charging the photoreceptor 210Y, and includes a charging roller 310Y, a cleaning roller 320Y, a pressing lever 330Y, a biasing member 340Y, and the like.

  The charging roller 310Y is a metal cylindrical member that charges the photosensitive layer of the photoreceptor 210Y to a negative voltage. The charging roller 310Y is provided at both ends thereof, and is provided at a shaft portion 311Y as an example of the “rotating shaft” of the charging roller 310Y, and at a central portion in the axial direction of the charging roller 310Y, and more than the shaft portion 311Y. And a large diameter portion 312Y having a large diameter. Of the peripheral surface of the charging roller 310Y, the peripheral surface of the large-diameter portion 312Y is an area for charging the photoreceptor 210Y. A conductive paint is applied to the surface of the large diameter portion 312Y so that the coating thickness is about 30 μm. Further, the charging roller 310Y is provided outside the large-diameter portion 312Y in the axial direction, and has a diameter larger than that of the large-diameter portion 312Y. The charging roller 310Y contacts the peripheral surface of the photoconductor 210Y and the photoconductor 210Y A gap forming portion 313Y for forming a gap with the large diameter portion 312Y is provided. The gap forming portion 313Y according to the present embodiment is formed by winding a film material around both ends of the large diameter portion 312Y. The charging roller 310Y forms the gap between the large diameter portion 312Y and the photoreceptor 210Y, and performs charging (so-called non-contact charging) in a state where the large diameter portion 312Y does not contact the photoreceptor 210Y. Do. In the case of non-contact charging, the gap needs to be maintained at 50 μm or less (preferably about 20 μm).

  In the present embodiment, as shown in FIG. 4, the charging roller 310Y is positioned below the central axis of the photoreceptor 210Y in a state where the central axis is along the central axis of the photoreceptor 210Y. The photoconductor unit 200Y is disposed. As shown in FIG. 5, the shaft portion 311Y of the charging roller 310Y is rotatably supported by a press lever 330Y described later, and the charging roller 310Y according to the present embodiment has an arrow direction ( That is, the photoconductor 210Y rotates in the opposite direction.

  The cleaning roller 320Y is a device that rotates in contact with the peripheral surface of the charging roller 310Y and removes dirt on the peripheral surface. The cleaning roller 320Y has a metal rotating shaft 321Y and a foamed portion 322Y formed by winding an elastic foam material around the central portion in the axial direction of the rotating shaft 321Y. The foaming portion 322Y of the cleaning roller 320Y includes a large diameter portion 312Y of the charging roller 310Y and a peripheral surface of the gap forming portion 313Y along the axial direction of the charging roller 310Y, as shown in FIG. It is in contact. That is, the cleaning roller 320Y can be in contact with the entire peripheral surface of the large diameter portion 312Y and the gap forming portion 313Y.

  Further, as shown in FIG. 4, the cleaning roller 320Y according to the present embodiment is below the central axis of the charging roller 310Y in a state where the central axis of the cleaning roller 320Y is along the central axis of the charging roller 310Y. It is arranged in the photoconductor unit 200Y so as to be positioned at the position. As shown in FIG. 5, the rotation shaft 321Y of the cleaning roller 320Y is rotatably supported by a press lever 330Y described later. The rotating shaft 321Y passes through the pressing lever 330Y on one end side in the axial direction of the cleaning roller 320Y (that is, the longitudinal direction of the photoconductor unit 200Y). In the present embodiment, the cleaning roller 320Y rotates in the direction of the arrow shown in FIG. 4 (that is, the same direction as the rotation direction of the photoreceptor 210Y). In this embodiment, the rotational speed (circumferential speed) of the cleaning roller 320Y is about 0.95 to 1.00 times the rotational speed (peripheral speed) of the photoreceptor 210Y. The cleaning roller 320Y does not rotate at a faster peripheral speed than the photoreceptor 210Y. However, the peripheral speed of the cleaning roller 320Y is not limited to this embodiment, and may be arbitrarily set, for example.

  The pressing lever 330Y is a member that supports the charging roller 310Y and the cleaning roller 320Y and presses the charging roller 310Y toward the photoreceptor 210Y. Further, as shown in FIG. 5, the pressing lever 330Y is provided on each of one end side and the other end side in the longitudinal direction of the photosensitive unit 200Y, and supports the charging roller 310Y and the cleaning roller. ing. Further, among the pressing levers 330Y, the pressing lever 330Y on one end side in the longitudinal direction is supported by a relay gear support shaft 505Y which will be described later, and the relays in the rotation direction indicated by arrows in FIG. It rotates around the gear support shaft 505Y.

  The biasing member 340Y is a member made of a spring, and one end of the biasing member 340Y is fixed to the pressing lever 330Y to bias the pressing lever 330Y. As described above, since the pressing lever 330Y is rotatable, the pressing lever 330Y receives the urging force from the urging member 340Y, thereby causing the charging roller 310Y supported by the pressing lever 330Y to move. The photoconductor 210Y rotates so as to be pressed. As a result, the gap forming portion 313Y of the charging roller 310Y can come into contact with the peripheral surface of the photoreceptor 210Y with a constant contact pressure, so that the charging roller 310Y is in contact with the large-diameter portion 312Y of the charging roller 310Y. The photoreceptor 210Y can be charged in a state where the gap formed between the photoreceptor 210Y is kept constant.

  The photoconductor unit frame 230Y is a member for housing the photoconductor 210Y, the charging device 300Y, a photoconductor cleaning unit 220Y described later, and the like. This photoconductor unit frame 230Y has shaft support portions 231Y that support the rotation shaft 212Y of the photoconductor 210Y and have a relay gear support shaft 505Y at both ends in the direction along the longitudinal direction of the photoconductor unit 200Y. is doing. Further, as shown in FIG. 3, the photosensitive unit frame 230Y is provided with a developing unit support portion 233Y for supporting the developing unit 50Y. Then, in a state where the developing unit 50Y is supported by the developing unit support portion 233Y, the developing unit 50Y and the photosensitive unit 200Y are connected by a connecting spring (not shown), so that the developing unit 50Y and the photosensitive unit 200Y are connected. Are integrated to form the process cartridge 15Y. Further, as shown in FIG. 3, the shaft support portion 231Y on one end side in the longitudinal direction of the photoconductor unit frame 230Y has a frame support shaft 235Y. On the other hand, the shaft support portion 231Y on the other end side in the longitudinal direction is provided with positioning holes 236Y in the upper and lower portions of the shaft support portion 231Y, respectively. The photosensitive unit 200Y (that is, the process cartridge 15Y) combined with the developing unit 50Y includes a rotation shaft 212Y of the photosensitive member 210Y that passes through the shaft support portion 231Y on one end side in the longitudinal direction, and the frame support shaft. It is positioned in the main body of the printer 10 through 235Y and the positioning hole 236Y and installed in the printer 10.

  The photoreceptor cleaning unit 220Y is an apparatus for scraping off the toner T remaining on the photoreceptor 210Y without being primarily transferred to the intermediate transfer belt 70. As shown in FIG. 4, a blade part 221Y and a blade support part are provided. 223Y and urging spring 229Y.

  The blade portion 221Y is a member made of rubber or the like, and scrapes off the toner T remaining on the photosensitive member 210Y when the edge of the tip portion contacts the photosensitive member 210Y. The contact position between the blade portion 221Y and the photoreceptor 210Y is above the contact position between the charging roller 310Y (more precisely, the gap forming portion 313Y of the charging roller 310Y) and the photoreceptor 210Y. .

  The blade support portion 223Y is a member having an L shape, and is for supporting the blade portion 221Y. Further, as shown in FIG. 4, fitting holes 226 </ b> Y for fitting into the photosensitive unit frame 230 </ b> Y are provided at the ends in the longitudinal direction of the blade support portion 223 </ b> Y (that is, the longitudinal direction of the photosensitive unit 200 </ b> Y). The fitting part 225Y provided with is provided. The blade support portion 223Y is rotatably supported by the photoconductor unit frame 230Y through the fitting hole 226Y. That is, the blade support portion 223Y can rotate around the center of the fitting hole 226Y.

  The urging spring 229Y is attached to the blade support portion 223Y and urges the blade support portion 223Y. And the said fitting part 225Y receives the urging | biasing force from the said urging | biasing spring 229Y, and rotates to the direction shown by the arrow in FIG. As a result, the blade support portion 223Y rotates as the fitting portion 225Y rotates, so that the tip of the blade portion 221Y comes into contact with the photoreceptor 210Y with a constant contact pressure. The part 221Y can be pressed.

  In the photoreceptor unit 200Y configured as described above, when the photoreceptor 210Y and the charging roller 310Y rotate, a DC voltage and an AC voltage are superimposed on the charging roller 310Y from the charging bias application unit 121 (see FIG. 2). The charged charging bias is applied. When the charging bias becomes a certain value (this value is referred to as a discharge start voltage) or more, a discharge occurs between the large diameter portion 312Y of the charging roller 310Y and the photosensitive member 210Y in a rotating state, The photoconductor 210Y is charged by the ions generated by the discharge. Then, the latent image is formed in a charged area on the outer peripheral surface of the photoreceptor 210Y, and the latent image is carried on the photoreceptor 210Y and moves. Thereafter, the latent image is developed as a single color toner image, and the single color toner image is primarily transferred to the intermediate transfer belt 70 as described above. Thereafter, the region of the outer peripheral surface of the photoreceptor 210Y where the primary transfer has been completed (that is, the region that has passed through the first contact portion T1) is the photoreceptor 210Y and the photoreceptor as the photoreceptor 210Y rotates. The cleaning unit 220Y reaches a contact portion with the blade portion 221Y. At the contact portion, the toner T remaining on the photoreceptor 210Y without being primarily transferred is scraped off by the blade portion 221Y. On the other hand, the region of the peripheral surface of the charging roller 310Y where the charging of the photoreceptor 210Y is completed reaches the contact portion between the charging roller 310Y and the cleaning roller 320Y as the charging roller 310Y rotates. In the contact portion, the adhering matter (for example, toner T transferred from the photoreceptor 210Y) adhering to the peripheral surface of the large diameter portion 312Y and the gap forming portion 313Y of the charging roller 310Y is removed from the cleaning roller 320Y. The area of the peripheral surface of the charging roller 310Y that has been charged is prepared for the next charging.

<<< Example of Configuration of Photoconductor Unit Driving Force Transmission Mechanism >>>
Next, referring to FIG. 5 and FIG. 6 described above, in the photoreceptor unit 200Y, the photoreceptor unit driving force for transmitting the driving force to the photoreceptor 210Y, the charging roller 310Y, and the cleaning roller 320Y. A transmission mechanism (hereinafter simply referred to as a driving force transmission mechanism) will be described.

  The driving force transmission mechanism includes a charging device gear 501Y as an example of a “first gear” for rotating the charging roller 310Y and a photosensitive device as an example of a “second gear” for rotating the photoreceptor 210Y. A body gear 502Y and a relay gear 503Y as an example of a “third gear” for receiving the driving force from the photosensitive member gear 502Y and transmitting the driving force to the charging device gear 501Y. I have. Each gear rotates in the direction indicated by the arrow in FIG.

  As shown in FIG. 5, the photoreceptor gear 502Y is provided on a flange 211Y on one end side in the longitudinal direction of the photoreceptor 210Y, out of the two flanges 211Y provided at both ends of the photoreceptor 210Y. Yes. The photoconductor gear 502Y meshes with a printer main body gear (not shown), and a driving force is transmitted from the printer main body gear. The photoconductor gear 502Y is supported on the rotary shaft 212Y of the photoconductor 210Y, like the photoconductor 210Y, and the central axis of the rotary shaft 212Y is driven by the driving force transmitted from the printer body gear. Around it, it rotates integrally with the photoreceptor 210Y.

  The relay gear 503Y is provided in the charging device 300Y. As shown in FIG. 6, the relay gear 503Y meshes with the photoconductor gear 502Y, and a driving force is transmitted from the photoconductor gear 502Y. Further, as shown in FIG. 5, the relay gear 503Y is supported by the relay gear support shaft 505Y, and the central axis of the relay gear support shaft 505Y is driven by the driving force transmitted from the photoconductor gear 502Y. Rotate around. Further, as described above, the relay gear support shaft 505Y is provided on the shaft support portion 231Y of the photoreceptor unit frame 230Y. Further, as described above, the relay gear support shaft 505Y supports the pressing lever 330Y and serves as a rotation shaft of the pressing lever 330Y. As shown in FIG. 5, the relay gear 503Y is located at a position outside the pressing lever 330Y in the axial direction of the relay gear support shaft 505Y (that is, the longitudinal direction of the photoreceptor unit 200Y). It is supported by the gear support shaft 505Y.

  The charging device gear 501Y is provided in the charging device 300Y. As shown in FIG. 6, the charging device gear 501Y meshes with the relay gear 503Y, and a driving force is transmitted from the relay gear 503Y. Further, as shown in FIG. 5, the charging device gear 501Y is supported by one end portion in the longitudinal direction of the rotation shaft 321Y of the cleaning roller 320Y that penetrates the pressing lever 330Y. The charging device gear 501Y rotates integrally with the cleaning roller 320Y around the central axis of the rotating shaft 321Y by the driving force transmitted from the relay gear 503Y.

  Incidentally, since the cleaning roller 320Y rotates in contact with the charging roller 310Y, the charging roller 310Y has a rotational direction of the cleaning roller 320Y due to friction between the charging roller 310Y and the cleaning roller 320Y. Rotate in the opposite direction. In other words, the cleaning roller 320Y rotates with the charging roller 310Y. That is, the charging device gear 501Y is a gear for rotating the cleaning roller 320Y, and also a gear for transmitting a driving force to the charging roller 310Y via the cleaning roller 320Y to rotate the charging roller 310Y. .

  In the driving force transmission mechanism configured as described above, the driving force is transmitted from the printer main body gear in the order of the photosensitive member gear 502Y, the relay gear 503Y, and the charging device gear 501Y, thereby the photosensitive member 210Y. The cleaning roller 320Y and the charging roller 310Y start to rotate sequentially.

  In the present embodiment, the respective gears of the photoconductor gear 502Y, the relay gear 503Y, and the charging device gear 501Y and the rotation shafts of the gears (for example, the relay gear 503Y and the relay gear). The support shaft 505Y) is a separate member. And although the said rotating shaft is supporting the said each gear in the state which passed through the shaft hole provided in each gear, it is not limited to this. For example, it is good also as using the member shape | molded so that it may have both a gear and a rotating shaft, and the said member being rotatably supported.

=== Effectiveness of Charging Device According to this Embodiment ===
As described above, the charging roller 310Y for charging the photoreceptor 210Y for carrying the latent image, the charging device gear 501Y for rotating the charging roller 310Y, and the photoreceptor 210Y are rotated. The relay gear 503Y for receiving the driving force from the photoconductor gear 502Y provided on the photoconductor 210Y and transmitting the driving force to the charging device gear 501Y, the charging roller 310Y, and the charging device A pressing lever 330Y that can rotate about the central axis of the relay gear 503Y to support the shaft of the gear 501Y and press the charging roller 310Y toward the photosensitive member 210Y, and the pressing lever 330Y. And a biasing member 340Y for biasing. As a result, the distance between the relay gear 503Y and the charging device gear 501Y can be stabilized, and the driving force can be appropriately transmitted from the relay gear 503Y to the charging device gear 501Y.

  That is, as described in the section of the problem to be solved by the invention, in order to appropriately charge the photoconductor 210Y, an interval between the photoconductor 210Y and the charging roller 310Y (that is, the photoconductor 210Y and the photoconductor 210Y). The gap formed between the charging roller 310Y and the large-diameter portion 312Y must be stabilized. That is, when the photoconductor 210Y rotates, the photoconductor 210Y is shaken. Therefore, it is necessary to adjust the position of the charging roller 310Y according to the shake. Therefore, when the pressing lever 330Y that supports the charging roller 310Y rotates in response to the shake of the photosensitive member 210Y in a state where the pressing lever 330Y is biased by the biasing member 340Y, the charging roller 310Y is connected to the charging roller 310Y. The position of the charging roller 310Y is adjusted by being pressed toward the photoconductor 210Y so that the distance from the photoconductor 210Y is maintained.

  However, for example, when the distance between the charging device gear 501Y and the relay gear 503Y changes as the pressing lever 330Y rotates, the third gear is appropriately driven to the first gear. There is a risk that power will not be transmitted. This problem will be described with reference to FIG. FIG. 7 is a diagram corresponding to FIG. 6 and shows the configuration of the driving force transmission mechanism of the photoreceptor unit 200Y in which the driving force may not be properly transmitted. In FIG. 7, the vertical direction is indicated by arrows as in FIG.

  In FIG. 7, the pressing lever 330Y is not supported by the relay gear support shaft 505Y, and is supported by another rotating shaft 550Y whose central axis does not coincide with the central axis of the relay gear 503Y. It rotates around the rotation axis 550Y. In this case, when the pressing lever 330Y rotates in the direction indicated by the symbol P, the charging device gear 501Y moves away from the relay gear 503Y. As a result, a meshing failure occurs between the charging device gear 501Y and the relay gear 503Y, and the driving force cannot be properly transmitted from the relay gear 503Y to the charging device gear 501Y.

  On the other hand, in the charging device 300Y according to the present embodiment, the pressing lever 330Y rotates around the center axis of the relay gear support shaft 505Y that supports the relay gear 503Y. As a result, the inter-shaft distance between the relay gear support shaft 505Y and the rotation shaft 321Y of the cleaning roller 320Y that supports the charging device gear 501Y is not changed by the rotation of the pressing lever 330Y. Therefore, since the distance between the relay gear 503Y and the charging device gear 501Y is stabilized, the driving force can be appropriately transmitted from the relay gear 503Y to the charging device gear 501Y.

  In the driving force transmission mechanism according to the present embodiment, the pressing lever 330Y is supported by the relay gear support shaft 505Y. However, the present invention is not limited to this. In order to stabilize the distance between the relay gear 503Y and the charging device gear 501Y, the center of rotation of the pressing lever 330Y and the center axis of the relay gear support shaft 505Y only have to coincide with each other. Therefore, for example, the pressing lever 330Y has a central axis that coincides with the central axis of the relay gear support shaft 505Y, and is supported by another support shaft different from the relay gear support shaft 505Y. It is good also as turning around the axis center of a support shaft.

=== Regarding Configuration Examples of Other Driving Force Transmission Mechanisms ===
In the above description, the driving force transmission mechanism when the charging roller 310Y rotates due to friction between the charging roller 310Y and the cleaning roller 320Y (hereinafter, this example) has been described. That is, although the charging roller 310Y is rotated by being indirectly transmitted with the driving force from the charging device gear 501Y, the present invention is not limited to this. Other examples of measures for appropriately transmitting the driving force to the charging roller 310Y with the distance between the relay gear 503Y and the charging device gear 501Y stabilized are also conceivable. Hereinafter, a driving force transmission mechanism according to another example (hereinafter, a modified example) will be described with reference to FIG. FIG. 8 is a diagram corresponding to FIG. 6 and is a schematic diagram showing a configuration of a driving force transmission mechanism according to a modification. In FIG. 8, similarly to FIG. 6, the vertical direction of the photoconductor unit 200Y is indicated by arrows.

  As shown in FIG. 8, the driving force transmission mechanism according to the modification has a photoconductor gear 502 </ b> Y similarly to the driving force transmission mechanism according to the present example. On the other hand, the driving force transmission mechanism according to the modification receives the driving force from the charging roller gear 511Y as an example of the “first gear” for rotating the charging roller 310Y and the photosensitive member gear 502Y, and A second relay gear 514Y as an example of a “third gear” for transmitting the driving force to the charging roller gear 511Y, and interposed between the photoconductor gear 502Y and the second relay gear 514Y. The first relay gear 512Y transmits the driving force transmitted from the photoconductor gear 502Y to the second relay gear 514Y. Each gear rotates in the rotation direction indicated by the arrow in FIG.

  The charging roller gear 511Y is supported by the shaft portion 311Y of the charging roller 310Y, and meshes with a second relay gear 514Y, which will be described later, as shown in FIG. 9, and receives driving force from the second relay gear 514Y. receive. The charging roller gear 511Y rotates integrally with the charging roller 310Y around the central axis of the shaft portion 311Y by the driving force transmitted from the second relay gear 514Y. That is, the charging roller 310Y according to this modification is rotated by receiving a driving force directly from the charging roller gear 511Y, unlike the case of this example. Note that the rotation direction of the charging roller 310Y according to this modification is opposite to the rotation direction of the photoconductor 210Y, similarly to the charging roller 310Y according to this example.

  The first relay gear 512Y is provided between the photoconductor gear 502Y and a second relay gear 514Y, which will be described later, and meshes with the photoconductor gear 502Y as shown in FIG. A driving force is received from the photoconductor gear 502Y. The first relay gear support shaft 513Y that supports the first relay gear 512Y is fixed to the shaft support portion 231Y of the photoreceptor unit frame 230Y.

  The second relay gear 514Y is provided between the first relay gear 512Y and the charging roller gear 511Y, and meshes with the first relay gear 512Y as shown in FIG. A driving force is received from the first relay gear 512Y. The second relay gear support shaft 515Y that supports the second relay gear 514Y is fixed and supported by the shaft support portion 231Y of the photoconductor unit frame 230Y, like the first relay gear support shaft 513Y. ing. Further, the second relay gear support shaft 515Y rotatably supports the pressing lever 330Y, and the pressing lever 330Y can rotate about the center of the second relay gear support shaft 515Y. Accordingly, since the interval between the second relay gear 514Y and the charging roller gear 511Y is stable, the driving force is appropriately transmitted from the second relay gear 514Y to the charging roller gear 511Y.

  Further, unlike the embodiment of the present example, the cleaning roller 320Y is not provided with a gear for transmitting a driving force to the cleaning roller 320Y. Therefore, the cleaning roller 320Y according to the present modification has a direction opposite to the rotation direction of the charging roller 310Y due to friction between the cleaning roller 320Y and the charging roller 310Y (that is, the rotation direction of the cleaning roller 320Y according to the present example). In the same direction). In other words, in this modification, the charging roller 310Y rotates with the cleaning roller 320Y.

  In the driving force transmission mechanism according to the modified example configured as described above, from the printer body gear, the photosensitive member gear 502Y, the first relay gear 512Y, the second relay gear 514Y, and the charging roller gear 511Y are arranged. The driving force is transmitted in order, and the photoreceptor 210Y, the charging roller 310Y, and the cleaning roller 320Y also start to rotate sequentially. At this time, since the charging roller 310Y receives the driving force directly from the charging roller gear 511Y, the driving force can be more appropriately transmitted to the charging roller 310Y.

  In the driving force transmission mechanism according to this modification, two relay gears are provided between the photoconductor gear 502Y and the charging roller gear 511Y. However, the present invention is not limited to this. . For example, only the second relay gear 514Y exists between the photoconductor gear 502Y and the charging roller gear 511Y, and the second relay gear 514Y directly meshes with the photoconductor gear 502Y, A driving force may be received from the photoconductor gear 502Y. Here, when two relay gears are provided between the photoconductor gear 502Y and the charging roller gear 511Y, the charging roller 310Y is opposite to the rotation direction of the photoconductor 210Y. Will rotate in the direction.

=== Other Embodiments ===
The image forming apparatus and the like according to the present invention have been described above based on the above embodiment. However, the above embodiment of the present invention is for facilitating understanding of the present invention and limits the present invention. is not. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes the equivalents thereof.

  In the above embodiment, the intermediate transfer type full color laser beam printer has been described as an example of the image forming apparatus. However, the present invention is not limited to the intermediate transfer type, but a full color laser beam printer, a monochrome laser laser beam printer, a copying machine, and a facsimile. The present invention can be applied to various image forming apparatuses.

  Further, in the above-described embodiment, the image forming apparatus including the tandem developing mechanism has been described. However, the present invention can be applied to an image forming apparatus including a rotary developing mechanism. it can.

  Further, the photosensitive member is not limited to a so-called photosensitive roller formed by providing a photosensitive layer on the peripheral surface of a cylindrical conductive substrate, and is configured by providing a photosensitive layer on the surface of the conductive substrate on the belt. A so-called photosensitive belt may also be used.

  In the above embodiment, the cleaning roller 320Y is supported by the pressing lever 330Y. However, the present invention is not limited to this. For example, the cleaning roller 320Y may be supported by a member different from the pressing lever 330Y. However, when the charging roller 310Y and the cleaning roller 320Y are both supported by the pressing lever 330Y, the distance between the axes of the charging roller 310Y and the cleaning roller 320Y is stabilized. Further, even when the charging roller 310Y bends due to the contact of the cleaning roller 320Y, the cleaning roller 320Y is supported by the same member as the charging roller 310Y. The abutting force exerted on is difficult to change. As a result, fluctuations in the amount of deflection of the charging roller 310Y due to the contact force are suppressed, so that the interval between the charging roller 310Y and the photoreceptor 210Y is stabilized. In view of the above, the above embodiment is more desirable. In particular, when the photosensitive member 210Y is charged by non-contact charging, the stability of the gap formed between the large diameter portion 312Y of the charging roller 310Y and the photosensitive member 210Y is particularly important. Is more advantageous.

  In the above embodiment, the charging roller 310Y has a large diameter portion 312Y having a diameter larger than that of the shaft portion 311Y of the charging roller 310Y and a diameter larger than that of the large diameter portion 312Y. There is a gap forming portion 313Y that is in contact with the peripheral surface to form a gap between the photoreceptor 210Y and the large diameter portion 312Y, and the large diameter portion 312Y and the photoreceptor 210Y are in contact with each other. The photosensitive member 210Y is charged in a state where there is not, but the present invention is not limited to this. For example, the large-diameter portion 312Y of the charging roller 310Y may be in contact with the peripheral surface of the photoreceptor 210Y and charge the photoreceptor 210Y by so-called contact charging. However, when the photosensitive member 210Y is charged without bringing the large-diameter portion 312Y of the charging roller 310Y into contact with the photosensitive member 210Y, adhered matter such as toner T adhering to the surface of the photosensitive member 210Y is transferred to the charging roller 310Y. Therefore, the photoreceptor 210Y can be appropriately charged. In this respect, the above embodiment is more desirable.

  In the above embodiment, the photoconductor unit frame 230Y for housing the photoconductor 210Y and the charging device 300Y is provided. The photoconductor unit frame 230Y (more precisely, the photoconductor) The shaft support portion 231Y) of the unit frame 230Y is supported by the rotation shaft 212Y of the photoreceptor 210Y that supports the photoreceptor gear 502Y and the relay gear support shaft 505Y. is not. For example, the rotation shaft 212Y of the photoreceptor 210Y and the relay gear support shaft 505Y may be supported by different members. However, when the rotation shaft 212Y of the photoreceptor 210Y and the relay gear support shaft 505Y are positioned by the same member, the tolerance for the distance between the two axes can be reduced, and further, the photoreceptor gear 502Y The tolerance of the interval with the relay gear 503Y can be reduced. As a result, the interval between the charging device gear 501Y and the relay gear 503Y and the interval between the photoconductor gear 502Y and the relay gear 503Y are stabilized. It is possible to appropriately transmit the driving force to the device gear 501Y. In this respect, the above embodiment is preferable.

=== Configuration of Image Forming System etc. ===
Next, an embodiment of an “image forming system” which is an example of an embodiment according to the present invention will be described with reference to the drawings.

  FIG. 9 is an explanatory diagram showing an external configuration of the image forming system. The image forming system 700 includes a computer 702, a display device 704, a printer 10, an input device 708, and a reading device 710.

  In this embodiment, the computer 702 is housed in a mini-tower type housing, but is not limited thereto. The display device 704 is generally a CRT (Cathode Ray Tube), a plasma display, a liquid crystal display device, or the like, but is not limited thereto. As the printer 10, the printer described above is used. In this embodiment, the input device 708 uses a keyboard 708A and a mouse 708B, but is not limited thereto. In this embodiment, the reading device 710 uses a flexible disk drive device 710A and a CD-ROM drive device 710B, but is not limited to this. For example, an MO (Magneto Optical) disk drive device or a DVD (Digital Versatile) is used. Disk) etc. may be used.

  FIG. 10 is a block diagram showing the configuration of the image forming system shown in FIG. An internal memory 802 such as a RAM and an external memory such as a hard disk drive unit 804 are further provided in a housing in which the computer 702 is housed.

  In the above description, an example in which the printer 10 is connected to the computer 702, the display device 704, the input device 708, and the reading device 710 to configure the image forming system has been described. However, the present invention is not limited to this. Absent. For example, the image forming system may include the computer 702 and the printer 10, and the image forming system may not include any of the display device 704, the input device 708, and the reading device 710.

  For example, the printer 10 may have a part of each function or mechanism of the computer 702, the display device 704, the input device 708, and the reading device 710. As an example, the printer 10 includes an image processing unit that performs image processing, a display unit that performs various displays, a recording medium attachment / detachment unit for attaching / detaching a recording medium that records image data captured by a digital camera or the like. It is good also as a structure to have.

  The image forming system realized in this way is a system superior to the conventional system as a whole system.

FIG. 2 is a diagram illustrating main components constituting the printer. 2 is a block diagram illustrating a configuration of a control unit 100 of the printer 10. FIG. It is a perspective view of the photoreceptor unit 200Y. FIG. 3 is a schematic diagram showing the appearance of a photoreceptor 210Y, a charging roller 310Y, a cleaning roller 320Y, and a photoreceptor cleaning unit 220Y in a state attached to the photoreceptor unit 200Y. It is a block diagram of the photoconductor unit 200Y, and is a view of the arrangement of the photoconductor 210Y, the charging device 300Y and the like as viewed from above. FIG. 6 is a schematic cross-sectional view of the photosensitive unit 200Y, and is a diagram illustrating main components in the II cross section of FIG. FIG. 7 is a diagram corresponding to FIG. 6 and shows a configuration of a driving force transmission mechanism of the photoconductor unit 200Y in which the driving force may not be properly transmitted. FIG. 8 is a schematic diagram illustrating a configuration of a driving force transmission mechanism according to a modification. 1 is an explanatory diagram showing an external configuration of an image forming system. It is a block diagram which shows the structure of the image forming system shown in FIG.

Explanation of symbols

10 Printer 15Y, 15M, 15C, 15K Process cartridge 40Y, 40M, 40C, 40K Exposure unit 50Y, 50M, 50C, 50K Developing unit 51Y, 51M, 51C, 51K Toner container 52Y, 52M, 52C, 52K Developing roller 53Y, 53M, 53C, 53K Supply roller 60Y, 60M, 60C, 60K Primary transfer unit 70 Intermediate transfer belt 80 Secondary transfer unit 85 Intermediate transfer belt cleaning unit 87 Intermediate transfer belt cleaning blade 90 Fixing unit 92 Paper feed tray 94 Paper feed roller 95 Display unit 96 Registration roller 97 Paper discharge roller 98 Paper discharge tray 100 Control unit 101 Main controller 102 Unit controller 112 Interface 113 Image memo 200Y, 200M, 200C, 200K Photoconductor unit 210Y, 210M, 210C, 210K Photoconductor 211Y Flange 212Y Rotating shaft 220Y, 220M, 220C, 220K Photoconductor cleaning unit 221Y Blade portion 223Y Blade support portion 225Y Fitting portion 226Y Fitting hole 229Y Energizing spring 230Y, 230M, 230C, 230K Photosensitive unit unit frame 231Y Shaft support portion 233Y Development unit support portion 235Y Frame support shaft 236Y Positioning hole 300Y, 300M, 300C, 300K Charging device 310Y Charging roller 311Y Shaft portion 312Y Large diameter portion 313Y Gap forming part 320Y Cleaning roller 321Y Rotating shaft 322Y Foaming part 330Y Pressing lever 340Y Energizing member 121 Charging by 501Y Charging device gear 502Y Photoconductor gear 503Y Relay gear 505Y Relay gear support shaft 511Y Charging roller gear 512Y First relay gear 513Y First relay gear support shaft 514Y Second relay gear 515Y First Dual relay gear support shaft 550Y Other rotating shaft 700 Image forming system 702 Computer 704 Display device 708 Input device 708A Keyboard 708B Mouse 710 Reading device 710A Flexible disk drive device 710B CD-ROM drive device 802 Internal memory T1 First contact Part T2 Second contact part T Toner

Claims (10)

A charging roller for charging an image carrier for carrying a latent image;
A first gear for rotating the charging roller;
A third gear for receiving a driving force from a second gear provided on the image carrier for rotating the image carrier and transmitting the driving force to the first gear;
A pressing lever that supports the charging roller and the shaft of the first gear and is rotatable about a central axis of the third gear to press the charging roller toward the image carrier;
A biasing member for biasing the pressing lever;
A charging device comprising: The charging device according to claim 1,
A charging device, wherein the pressing lever is supported by a cleaning roller that contacts the peripheral surface of the charging roller to remove dirt on the peripheral surface. The charging device according to claim 2,
The axis of the first gear is a rotation axis of the cleaning roller;
The first gear rotates the cleaning roller while the cleaning roller is in contact with the charging roller, and rotates the charging roller by friction between the charging roller and the cleaning roller. Charging device. The charging device according to claim 2,
The charging device, wherein the first gear is provided on the charging roller. The charging device according to any one of claims 2 to 4,
The charging roller is
A large diameter portion having a diameter larger than the rotating shaft of the charging roller;
A gap forming portion having a diameter larger than that of the large-diameter portion and abutting on a peripheral surface of the image carrier to form a gap between the image carrier and the large-diameter portion;
And charging the image carrier in a state where the large diameter portion and the image carrier are not in contact with each other. A charging roller for charging an image carrier for carrying a latent image;
A first gear for rotating the charging roller;
A third gear for receiving a driving force from a second gear provided on the image carrier for rotating the image carrier and transmitting the driving force to the first gear;
A pressing lever that supports the charging roller and the shaft of the first gear and is rotatable around a central axis of the third gear to press the charging roller toward the image carrier;
A biasing member for biasing the pressing lever;
With
The axis of the first gear is a rotation axis of the cleaning roller;
The first gear rotates the cleaning roller while the cleaning roller is in contact with the charging roller, and rotates the charging roller by friction between the charging roller and the cleaning roller.
The charging roller is
A large diameter portion having a diameter larger than the rotating shaft of the charging roller;
A gap forming portion having a diameter larger than that of the large-diameter portion and abutting on a peripheral surface of the image carrier to form a gap between the image carrier and the large-diameter portion;
And charging the image carrier in a state where the large diameter portion and the image carrier are not in contact with each other. An image carrier for carrying a latent image;
A second gear provided on the image carrier for rotating the image carrier;
To receive a driving force from a charging roller for charging the image carrier, a first gear for rotating the charging roller, and the second gear, and to transmit the driving force to the first gear. A third gear, a pressure lever that supports the charging roller and the shaft of the first gear, and is rotatable about a central axis of the third gear to press the charging roller toward the image carrier. An urging member for urging the pressing lever; and a charging device comprising:
A cartridge characterized by comprising: The cartridge according to claim 7, wherein
A housing for accommodating the image carrier and the charging device;
The cartridge is characterized in that a rotation shaft of an image carrier provided with the second gear and a shaft of a third gear are supported on the housing. An image carrier for carrying a latent image;
A second gear provided on the image carrier for rotating the image carrier;
To receive a driving force from a charging roller for charging the image carrier, a first gear for rotating the charging roller, and the second gear, and to transmit the driving force to the first gear. A third gear, a pressure lever that supports the charging roller and the shaft of the first gear, and is rotatable about a central axis of the third gear to press the charging roller toward the image carrier. An urging member for urging the pressing lever; and a charging device comprising:
An image forming apparatus comprising: a cartridge having a cartridge. Computer and
An image forming apparatus connectable to the computer,
An image carrier for carrying a latent image;
A second gear provided for rotating the image carrier;
To receive a driving force from a charging roller for charging the image carrier, a first gear for rotating the charging roller, and the second gear, and to transmit the driving force to the first gear. A third gear, a pressure lever that supports the charging roller and the shaft of the first gear, and is rotatable about a central axis of the third gear to press the charging roller toward the image carrier. An urging member for urging the pressing lever; and a charging device comprising:
An image forming system comprising an image forming apparatus provided with a cartridge having

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