JP2006178506A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus miniaturization of which is realized while achieving stable belt behavior and improved cleaning performance. <P>SOLUTION: The image forming apparatus includes: an image carrier belt; a frame supporting the image carrier belt; a belt support means movably supported by the frame and supporting the image carrier belt; a cleaning member cleaning the surface of the image carrier belt; an auger member conveying toner recovered by the cleaning member; a casing holding the cleaning member and the auger member; a casing holding the cleaning member and the auger member; and a linking mechanism disposed between the belt support member and the casing and retaining a relative positional relation between the belt support means and the cleaning member. The casing is attached to/detached from the frame together the cleaning member and the auger member. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine or a printer using an electrophotographic method, and in particular, an image carrier belt, a belt support member that supports the image carrier belt, and an image carrier by moving the belt support member. The present invention relates to an image forming apparatus including a belt movement control device that controls movement of a body belt in the belt width direction and a belt cleaning device that cleans the surface of an image carrier belt.

Japanese Examined Patent Publication No. 63-064792 Japanese Patent Laid-Open No. 03-288167 Japanese Patent Laid-Open No. 06-056296 Japanese Patent Laid-Open No. 06-064772 Japanese Patent Laid-Open No. 08-123120 Japanese Patent Application Laid-Open No. 09-222827 JP 57-017973 A JP 07-271142 A

  In an image forming apparatus, an endless intermediate transfer belt that carries a toner image in the transfer process or an endless sheet conveyance belt that carries and conveys a recording sheet is used, and the intermediate transfer belt or sheet conveyance belt used in the transfer process is used. A so-called tandem type color image forming apparatus in which four image forming units that form cyan, magenta, yellow, and black toner images are arranged to face each other to form a multicolor image. In addition, an endless photoconductor belt is used as a photoconductor in the image forming process, and four developing units of cyan, magenta, yellow, and black are arranged facing each other on the photoconductor belt. There is a color image forming apparatus that forms a toner image by supplying toner from each developing unit to a latent image formed on a body belt.

  An endless intermediate transfer belt, a sheet conveying belt, and a photosensitive belt (hereinafter collectively referred to as “image carrier belt”) used in such an image forming apparatus drive at least the image carrier belt. The drive roll is supported by a plurality of rolls including a drive roll having a drive function and a tension roll having a tension applying function for applying tension to the image carrier belt, and the drive roll while applying tension to the image carrier belt with the tension roll. The rotational drive is given to the image carrier belt.

  However, such an image carrier belt has a phenomenon that it moves in the belt width direction (direction perpendicular to the belt rotation direction) during traveling due to the mounting error of a plurality of rolls that support the belt, that is, the belt meanders. The phenomenon (belt walk) inevitably occurs.

  For example, in a tandem color image forming apparatus in which the image forming apparatus uses an intermediate transfer belt in the transfer process, each single color toner image is transferred from each image forming unit onto the intermediate transfer belt. These monochromatic toner images are superposed. However, when a meandering phenomenon occurs in the intermediate transfer belt in such a tandem type color image forming apparatus, the relative positional relationship of the monochromatic toner images is shifted. And image defects such as color misregistration and color unevenness occur, and a high-quality color image cannot be obtained.

  Therefore, conventionally, in order to solve such a problem, a roll capable of tilting operation (hereinafter referred to as “belt support roll”) is adopted as one of a plurality of rolls that support the image carrier belt, When a meandering phenomenon occurs in the image carrier belt, the sensor detects the meandering of the image carrier belt, and controls the inclination of the belt support roll based on the detection result to move the belt to properly correct the meandering phenomenon. Control devices have been proposed (see, for example, Patent Literature 1, Patent Literature 2, Patent Literature 3, Patent Literature 4, Patent Literature 5, and Patent Literature 6).

  Further, it is extremely difficult to achieve 100% transfer efficiency of the toner image in the image carrier belt of such an image forming apparatus, and a part of the toner remains on the image carrier belt in the transfer process. Alternatively, in the case of the sheet conveying belt, the residual toner on the photosensitive member side is transferred, and this residual toner causes various image defects, so that it is indispensable to use a belt cleaning device. However, in this belt cleaning device, since the object to be cleaned is a flexible belt, there are problems with cleaning performance, chattering of the cleaning blade, etc., and various measures have been taken to solve these problems in the past. (See, for example, Patent Document 7 and Patent Document 8). For example, Patent Document 8 includes a lubricant application brush and a cleaning blade. The lubricant is applied to the surface of the intermediate transfer belt with the lubricant application brush while detecting environmental temperature, humidity, and rotational torque, and then cleaned. It has been proposed to clean the surface of the intermediate transfer belt with a blade.

Therefore, in an image forming apparatus using an image carrier belt, it is essential to improve the cleaning performance while stabilizing the behavior of the image carrier belt, and it is necessary to apply a device for that purpose. However, for example, when a belt cleaning device including a lubricant application brush and a cleaning blade is laid on the image carrier belt, a backup roll is disposed on the image carrier belt so as to face the lubricant application brush and the cleaning blade. The configuration of the image carrier belt tends to increase in size such as necessity, which is a problem from the viewpoint of reducing the size of the apparatus itself.

  The present invention has been invented based on such a viewpoint. The object of the present invention is to provide a belt movement control device for controlling the movement of the belt in the belt width direction, a belt cleaning device for cleaning the surface of the image carrier belt, and the like. In the image forming apparatus having the above, an image forming apparatus capable of achieving downsizing of the apparatus while stabilizing the belt behavior and improving the cleaning performance is provided.

  That is, the present invention provides an image carrier belt, a belt support member that supports the image carrier belt, and a belt movement that controls movement of the image carrier belt in the belt width direction by moving the belt support member. An image forming apparatus including a control device and a belt cleaning device that cleans the surface of the image carrier belt, and is provided on the belt support member and the belt cleaning device to clean the belt surface of the image carrier belt. An interlocking mechanism that changes the posture of the cleaning member in accordance with the change of the posture of the belt support member is provided between the cleaning member and the belt support when the belt movement control operation of the belt support member is performed by the interlocking mechanism. A relative positional relationship between a member and the cleaning member is maintained; A dynamic control device having a movable frame that supports the belt support member and performs a belt movement control operation of the belt support member, the belt cleaning device has a casing that holds the cleaning member as a unit, and the interlocking An image forming apparatus characterized in that a mechanism is achieved by detachably attaching the casing to the movable frame.

  The present invention relates to a photosensitive belt used in an image forming process when the image carrier belt is an intermediate transfer belt that supports a toner image in a transfer process, or a sheet transport belt that supports and conveys a recording sheet in a transfer process. In particular, the image carrier belt is an intermediate transfer belt that carries a toner image in a transfer process, and includes four primary transfer rolls for yellow, magenta, cyan, and black. The present invention can be preferably applied to an intermediate transfer belt used in a tandem type color image forming apparatus provided.

  In the present invention, the belt support member constituting the belt movement control device applies tension to the image carrier belt even if it is a steering drive roll having a drive function for driving the image carrier belt. The tension applying function may be provided, and can be determined by the layout of the entire apparatus and the positional relationship with the image forming unit, the developing unit, the belt cleaning device, and other members disposed on the image carrier belt. In the present invention, both the belt support member having a drive function and the belt support member having a steering function are advantageous in that the overlap region where the belt and the support member overlap is large in order to effectively exhibit the respective functions. In addition, since the overlap region is limited to a total of 360 ° when viewed from the angle at which the belt and the support member overlap, from the viewpoint of achieving downsizing of the apparatus while stabilizing the belt behavior and improving the cleaning performance. In this case, the belt support member is preferably a steering drive roll having a drive function.

  Furthermore, in the present invention, a brush-type cleaning brush or a blade-type cleaning blade can be suitably applied to the cleaning member constituting the belt cleaning device. In particular, the cleaning member does not need to have a retracting mechanism and can be easily downsized. Therefore, it is preferable that the cleaning member is a constant contact cleaning member that always contacts the surface of the image carrier belt.

  In particular, the cleaning member is an always-contact type cleaning blade that always contacts the surface of the image carrier belt, and a part of the collected toner scraped off from the surface of the image carrier belt stays at the tip of the cleaning blade. A type that performs a lubrication function, a constant contact type cleaning blade in which the belt cleaning device is always in contact with the surface of the image carrier belt, and collected toner scraped from the surface of the image carrier belt in the toner collection box And a paddle that feeds the collected toner scraped off on the belt surface to the auger, and a type in which a predetermined amount of the collected toner is supplied to the tip of the cleaning blade by rotation of this paddle. Used for.

  In the present invention, in order to ensure excellent cleaning performance in the belt cleaning device, an interlocking mechanism that changes the posture of the cleaning member according to the change in the posture of the belt support member between the belt support member and the cleaning member. It is necessary to maintain the relative positional relationship between the belt support member and the cleaning member during the belt movement control operation of the belt support member.

  The interlocking mechanism provided between the belt support member and the cleaning member is not particularly limited as long as it is a means capable of maintaining the relative positional relationship between them. For example, the movable frame that performs the belt movement control operation of the belt support member is cleaned. Directly attaching members, attaching a belt cleaning device unitized using a housing to the movable frame of the belt support member, detachably connecting the movable frame of the belt support member and the movable frame of the cleaning member, etc. Can be mentioned.

  Here, with respect to the relative positional relationship between the belt support member and the cleaning member, the contact position between the image carrier belt and the cleaning member in the cleaning mode of the belt cleaning device is determined by the relationship between the image carrier belt and the belt support member. It should be in the overlap region from the contact start position upstream of the overlapping belt rotation direction to the contact end position downstream of the belt rotation direction, so that even if the belt support member performs the belt movement control operation, the cleaning is performed. The member can reliably clean the image carrier belt. More preferably, the contact position is within the overlap region, and the belt slip occurs from the contact end position from the downstream side position in the belt rotation direction where the shaking due to the mounting error does not occur from the contact start position. It should be in the stable region up to the upstream position in the belt rotation direction, which makes it possible to provide excellent belt movement control performance, belt drive performance, and cleaning performance even when a steering drive roll is used as the belt support member. It can be demonstrated. Here, the stable region is experimentally considered in consideration of the size of the overlap region of the belt support member, the surface roughness of the belt support member, the friction resistance between the surface of the image carrier belt and the cleaning member, and the like. It can be easily obtained.

  In the present invention, in order to achieve downsizing of the apparatus while stabilizing the belt behavior and improving the cleaning performance, the following can be mentioned as preferable configurations. (1) The image carrier belt is an intermediate transfer belt that carries a toner image in the transfer process, the belt support member is a steering drive roll having a drive function for driving the intermediate transfer belt, and the cleaning member is (2) An image carrier belt is an intermediate transfer belt that carries a toner image in a transfer process, and a belt support member holds the intermediate transfer belt on the surface of the intermediate transfer belt. This is a steering drive roll having a drive function to drive, and a cleaning blade whose contact is constantly contacted with the surface of the image carrier belt, and the collected toner scraped from the surface of the image carrier belt. A structure in which a part stays at the tip of the cleaning blade and performs the lubrication function. (3) Bell The cleaning device is always in contact with the surface of the image carrier belt, the cleaning blade is always contacted, the auger that transports the collected toner scraped from the surface of the image carrier belt into the toner collection box, and the belt surface. There is a configuration including a paddle that feeds the collected toner to the auger, and a predetermined amount of the collected toner is supplied to the tip portion of the cleaning blade by the rotation of the paddle.

  The present invention also provides an image carrier belt, a frame for supporting the image carrier belt, a belt support means supported to be movable with respect to the frame, and supporting the image carrier belt, and the image A cleaning member for cleaning the surface of the carrier belt, an auger member for conveying toner collected by the cleaning member, a casing for holding the cleaning member and the auger member, and between the belt support means and the casing An interlocking mechanism for maintaining a relative positional relationship between the belt support means and the cleaning member, and the casing has the cleaning member and the auger member, The image forming apparatus is detachable from the frame.

  In the present invention, the belt support member may have a tension applying function for applying tension to the image carrier belt.

  An image carrier belt, a belt support member that supports the image carrier belt, a belt movement control device that controls movement of the image carrier belt in the belt width direction by moving the belt support member, and a surface of the image carrier belt In the image forming apparatus including the belt cleaning device for cleaning the belt, the relative positional relationship between the belt support member responsible for the belt movement control operation and the cleaning member for cleaning the belt surface of the image carrier belt can be maintained. A plurality of rolls that have at least a drive roll and a tension roll to support the image carrier belt, and the belt cleaning is performed while maintaining the cleaning performance regardless of which of these rolls functions as a belt support member. A device that can support the image carrier belt The device size can be reduced by reducing the number of devices and the device size can be easily reduced.In addition, the scope of application of this device size reduction is expanded, and the device is improved while stabilizing the belt behavior and improving the cleaning performance. Can be miniaturized.

Hereinafter, preferred embodiments of the present invention will be specifically described based on examples.
[Example 1]
1 and 2 show a tandem type color image forming apparatus using an intermediate transfer belt according to an embodiment of the present invention. This color image forming apparatus includes an intermediate transfer belt (image carrier belt) 1, a steering drive roll (belt support member) 2 that supports the intermediate transfer belt 1, a tension roll 3, and a secondary transfer backup roll 4. A yellow image forming unit 5, a magenta image forming unit 6, a cyan image forming unit 7 disposed between the steering drive roll 2 and the tension roll 3 so as to face the intermediate transfer belt 1, and A second image forming unit 8 for black, a belt cleaning unit 9 disposed in the vicinity of the steering drive roll 2, and a secondary transfer roll 10 a disposed opposite to the secondary transfer backup roll 4. An electrostatic latent image is formed on the next transfer device 10 and the photosensitive drums 5a to 8a of the image forming units 5 to 8. A ROS (Raser Output Scanner) unit 11 for writing, a paper (recording sheet) tray unit 12, and a fixing unit 13 are provided.

  Here, the image forming units 5 to 8 have developing devices 5b to 8b corresponding to the respective colors adjacent to the photosensitive drums 5a to 8a, and the developing devices 5b to 8b are not shown. The toner of each color is supplied from the toner cartridges 14 to 17 corresponding to each color by the toner supply means. In the figure, reference numerals 18 to 21 denote primary transfer backup rolls arranged to face the photosensitive drums 5a to 8a of the image forming units 5 to 8, respectively.

  In the color image forming apparatus of the first embodiment, the single color toner images formed by the image forming units 5 to 8 are superimposed on the intermediate transfer belt 1 to form a multicolor toner image. The secondary transfer device 10 is transferred to the secondary transfer device 10 where it is secondarily transferred onto the paper supplied from the paper tray unit 12 as indicated by the paper route P, and then passed through the fixing unit 13 to the outside of the device. To be discharged.

  The belt cleaning unit 9 used in the first embodiment is a blade type belt cleaning device as shown in FIGS. 3 and 4, and a cleaning blade (cleaning member) is provided in the casing 9a. 9b, a paddle 9c, and an auger 9d. The casing 9a is sealed with an upper seal 9e.

  In the first embodiment, as shown in FIGS. 3 to 5, the steering drive roll 2 is rotatably supported by the block main 1b forming the transfer body frame 1a of the intermediate transfer belt 1. A movable frame 22 is disposed, and a casing 9a of the belt cleaning unit 9 is detachably attached to the movable frame 22.

  The movable frame 22 includes a block main 22a positioned opposite to the block main 1b on the transfer body frame 1a side, an inner frame 22b and an outer frame 22c attached to both ends of the block main 22a, and a steering. The drive roll 2 is rotatably supported between the inner frame 22b and the outer frame 22c of the movable frame 22.

  Between the block main 1b forming the transfer body frame 1a of the intermediate transfer belt 1 and the block main 22a of the movable frame 22, a pivot 23 is located on the inner side in the belt width direction of the intermediate transfer belt 1 (upper side in FIG. 3). Is fixed to the block main 22a of the movable frame 22, and the distal end side of the pivot 23 is rotatably fitted in a through hole 24 formed on the block main 1b side of the transfer body frame 1a. 3 can be displaced in the vertical direction with the pivot 23 as a rotation axis, and is shown in FIGS. 3, 5, and 6 on the outer side in the belt width direction of the intermediate transfer belt 1 (lower side in FIG. 3). As shown in the figure, a roller 25 is mounted on the block main 1b side of the transfer body frame 1a, and the pivot 23 and the roller 25 enable the block main 1b of the transfer body frame 1a. The block main 22a of the frame 22 is accurately maintain a predetermined distance d are parallel to each other.

  A steering cam 26 is disposed below the outer frame 22c constituting the movable frame 22, and the outer frame 22c of the movable frame 22 is placed on the steering cam 26, and The steering cam 26 is driven by a steering motor 27 controlled by a signal from a sensor (not shown) that detects the meandering phenomenon of the intermediate transfer belt 1.

  Therefore, in this embodiment, when a meandering phenomenon occurs in the intermediate transfer belt 1, the steering motor 27 rotates by a predetermined amount in a predetermined direction by a signal from a sensor that detects the meandering of the intermediate transfer belt 1, The movable frame 22 is displaced up and down on the outer frame 22c with the pivot 23 as a rotation axis, and the steering drive roll 2 attached to the movable frame 22 changes its posture for the belt movement control operation. However, the cleaning blade 9b of the belt cleaning unit 9 attached to the movable frame 22 also changes its posture in accordance with the posture change caused by the belt movement control operation of the steering drive roll 2, and the steering drive roll 2 and the cleaning blade 9b. The relative positional relationship between is maintained.

  In the first embodiment, as shown in FIG. 5, a block main 1b of the transfer body frame 1a and a block main 22a of the movable frame 22 are provided between the outer side of the transfer body frame 1a and the outer frame 22c of the movable frame 22. A tension spring 28 is provided to urge the outer frame 22c of the movable frame 22 toward each other, and to urge the outer frame 22c of the movable frame 22 to approach the steering cam 26, thereby blocking the transfer body frame 1a. The parallelism between the main 1b and the block main 22a of the movable frame 22 is not impaired, and the movement of the steering cam 26 is accurately transmitted to the movable frame 22 side without play.

  In the first embodiment, as shown in FIGS. 3 and 5, a pin 9 f provided on the belt cleaning unit 9 side and the movable frame 22 are provided between the belt cleaning unit 9 and the movable frame 22. It is positioned by a pin hole 22e provided in the inner frame 22b of the inner frame 22b, and between the block main 22a of the movable frame 22 and the inner frame 22b and the outer frame 22c, and between the inner frame 22b and the outer frame 22c and the rear frame 22d. And between the casing 9a of the belt cleaning unit 9 and the outer frame 22c of the movable frame 22 are fixed by mounting screws 29.

  Therefore, as shown in FIG. 5, the belt cleaning unit 9 can be easily removed from the movable frame 22 by removing the mounting screws 29 that connect the casing 9a and the rear frame 22d and the outer frame 22c of the movable frame 22. The recovered toner collected from the surface of the intermediate transfer belt 1 by the cleaning blade 9b and fed into the toner collection box (not shown) through the pawl 9c and the auger 9d reaches a predetermined amount. When it reaches, the belt cleaning unit 9 can be replaced. In the belt cleaning unit 9, a toner collection box may be detachably attached, and only the toner collection box may be detached so that the collected toner can be discarded.

  Furthermore, in the first embodiment, as shown in FIGS. 9 and 10, the steering drive roll 2 has a diameter of 30 mm, and the vertical movement width w by the belt movement control operation is set to a maximum of 5 mm. The contact position p where the cleaning blade 9b contacts the intermediate transfer belt 1 is downstream from the contact start position 30 upstream of the belt rotation direction where the steering drive roll 2 and the intermediate transfer belt 1 overlap. In the overlap region up to the contact end position 31 on the side, the distance is set to 7.9 mm downstream from the contact start position 30 in the belt rotation direction.

The cleaning blade 9b is made of a urethane rubber material, and is set to a blade set angle (Blade Set Angle; BSA) of 22 ° and a blade biting amount of 1.1 mm. Further, the steering drive roll 2 is formed of an alumite-treated aluminum bar, and its surface roughness is formed to _Ra 1.6. Further, the intermediate transfer belt 1 has a Young's modulus of 370 kgf / mm ² and a surface roughness of _Ra 6.0.

  When the test operation of the color image forming apparatus of Example 1 was performed with such a set value, the intermediate transfer belt 1 did not slip in the belt rotation direction even during the belt movement control operation by the steering drive roll 2. Also, no cleaning failure was observed. During this time, the collected toner T scraped off by the cleaning blade 9b is always supplied to the tip of the cleaning blade 9b by the paddle 9c, and between the tip of the cleaning blade 9b and the intermediate transfer belt 1 Presents good lubrication performance.

  Note that the contact position p where the cleaning blade 9b contacts the intermediate transfer belt 1 is within the overlap region, and the mounting error of the cleaning blade 9b, the steering drive roll 2, etc. can be absorbed from the contact start position 30. In other words, even if such an attachment error occurs and the overlap region fluctuates, the position shifted from the downstream side in the belt rotation direction as much as possible within the overlap region, as shown in FIG. From the contact end position 31, until the belt slip is not caused, in other words, until the grip force of the cleaning blade 9b and the intermediate transfer belt 1 becomes larger than the grip force of the intermediate transfer belt 1 and the steering drive roll 2, the belt rotation direction It is desirable to be in the stable region up to the position that has moved upstream. In the first embodiment, the stable region extends from a position shifted by 3 mm downstream of the belt rotation direction from the contact start position 30 to a position shifted by 5 mm upstream of the belt rotation direction from the contact end position 31. It is a range.

  Furthermore, in the first embodiment, the distance d between the block main 1b of the transfer body frame 1a and the block main 22a of the movable frame 22 is accurately maintained by using the pivot 23 and the roller 25, and the parallelism between the two is maintained. However, instead of the roller 25, as shown in FIG. 12, the movable frame 22 is made of a resin having excellent slipperiness on the side of the block main 22a (or the block main 1b of the transfer body frame 1a). The spacer 32 may be provided.

[Example 2]
FIG. 13 shows a tandem color image forming apparatus according to Embodiment 2 of the present invention. Unlike the case of Embodiment 1, the sheet transport belt is used in the transfer process.

  In the second embodiment, unlike the first embodiment, a sheet conveying belt (image carrier belt) 100 that sucks and conveys a sheet (recording sheet), a drive roll 101 that supports the sheet conveying belt 100, a steering, An image forming unit for yellow arranged to be opposed to the sheet conveying belt 100 between the tension roll (belt support member) 102, the backup roll 104 of the sheet suction roll 103, and the drive roll 102 and the backup roll 104; 105, a magenta image forming unit 106, a cyan image forming unit 107, a black image forming unit 108, a belt cleaning unit 109 disposed in the vicinity of the steering / tension roll 102, and the image forming units 105. ROS (Raser Outpu) for writing an electrostatic latent image on each of the 108 photosensitive drums 105a to 108a t Scanner) unit 111, a paper (recording sheet) tray unit 112, and a fixing unit 113.

  Here, each of the image forming units 105 to 108 has the same configuration as that of the first embodiment, and toner of each color is supplied from toner cartridges 114 to 117 corresponding to each color by a toner supply unit (not shown). In addition, backup rollers 118 to 121 for primary transfer are disposed so as to face the photosensitive drums 5a to 8a.

  In the color image forming apparatus of the second embodiment, the single color toner images formed by the image forming units 105 to 108 are supplied from the paper tray unit 112 as indicated by the paper route P, and the sheet conveying belt 101 is used. Are sequentially transferred onto a sheet conveyed by being attracted by electrostatic force to form a multicolor toner image, and then discharged through the fixing unit 13 to the outside of the apparatus.

  Also in the second embodiment, the steering / tension roll 102 between the steering / tension roll (belt support member) 102 constituting the belt movement control device and the cleaning blade 109b of the belt cleaning unit 109 is the same as in the first embodiment. An interlocking mechanism is provided for changing the posture of the cleaning blade 109b in accordance with the change in posture of the steering wheel. When the steering movement of the steering / tension roll 102 is controlled, the cleaning blade of the steering / tension roll 102 and the belt cleaning unit 109 is provided. The relative positional relationship with 109b is maintained. In the case of Example 2, as in Example 1, stabilization of belt behavior and improvement of cleaning performance could be achieved at the same time.

Example 3
FIG. 14 shows a color image forming apparatus according to Embodiment 3 of the present invention. Unlike the cases of Embodiments 1 and 2, a photoreceptor belt is used as the photoreceptor used in the image forming process. .

  This color image forming apparatus includes a photoreceptor belt (image carrier belt) 201, a steering drive roll (belt support member) 202 that supports the photoreceptor belt 201, a backup roll 203 for a charging roll 205, and a primary transfer. A yellow developing unit 205 disposed between the backup roll 204 of the transfer roll 206, the backup roll 203 of the charging roll 205, and the backup roll 204 of the transfer roll 206 so as to face the photosensitive belt 201, and magenta A developing unit 206, a cyan developing unit 207, a black developing unit 208, and a belt cleaning unit 209 disposed in the vicinity of the steering drive roll 202 are provided.

  In the color image forming apparatus of the third embodiment, a predetermined charge is applied to the photosensitive belt 201 by the charging roll 205, and then a predetermined electrostatic latent image is written by the exposure device 210, and developed by the developing units 205 to 208. As a result, the multi-color toner image is transferred from a paper cassette (not shown) to a paper sheet P transferred by a transfer roller 206 and transferred to a paper route P. It is discharged outside.

  Also in the third embodiment, the steering / drive roll 202 between the steering / drive roll (belt support member) 202 constituting the belt movement control device and the cleaning blade 209b of the belt cleaning unit 209 is the same as in the first embodiment. An interlocking mechanism for changing the posture of the cleaning blade 209b in accordance with the change of the posture of the steering drive roller 202 and the cleaning blade of the belt cleaning unit 209 during the belt movement control operation of the steering drive roller 202 is provided. The relative positional relationship with 209b is maintained. In the case of Example 3, as in Example 1, stabilization of the belt behavior and improvement of the cleaning performance could be achieved at the same time.

FIG. 1 is a schematic explanatory diagram of a tandem color image forming apparatus according to Embodiment 1 of the present invention. FIG. 2 is a partial explanatory view showing the periphery of the intermediate transfer belt in FIG. 1 in an enlarged manner. 3 is a partially enlarged explanatory view showing the belt cleaning unit 9 disposed in the vicinity of the steering / drive roll 2 in FIG. FIG. 4 is a sectional view taken along line IV-IV in FIG. FIG. 5 is an exploded view of the part shown in FIG. FIG. 6 is an explanatory cross-sectional view showing the roller attached to the block main of the transfer body frame in FIG. FIG. 7 is a cross-sectional explanatory view showing the pivot attached between the block main of the movable frame and the block main of the transfer body frame in FIG. FIG. 8 is a sectional view taken along line VIII-VIII in FIG. FIG. 9 is an explanatory view showing a contact position of the cleaning blade with respect to the intermediate transfer belt. FIG. 10 is an explanatory diagram showing a state where the recovered toner is supplied to the tip portion of the cleaning blade in the belt cleaning device. FIG. 11 is an explanatory view similar to FIG. FIG. 12 is a cross-sectional explanatory view showing a spacer attached in place of the roller of FIG. FIG. 13 is a schematic explanatory diagram of a tandem color image forming apparatus according to Embodiment 2 of the present invention. FIG. 14 is a schematic explanatory diagram of a color image forming apparatus according to Embodiment 3 of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Intermediate transfer belt (image carrier belt), 2 ... Steering drive roll (belt support member), 3 ... Tension roll, 4 ... Backup roll for secondary transfer, 5 ... Image forming unit for yellow, 6 ... For magenta Image forming unit, 7 ... Image forming unit for cyan, 8 ... Image forming unit for black, 9 ... Belt cleaning unit, 9a ... Case, 9b ... Cleaning blade (cleaning member), 9c ... Paddle, 9d ... Auger, 22 ... Movable Frame, p ... contact position, 30 ... contact start position, 31 ... contact end position, T ... collected toner, 100 ... sheet conveying belt (image carrier belt), 101 ... drive roll, 102 ... steering tension roll (belt support) Members), 105 ... yellow image forming unit, 106 ... magenta image forming unit, 107 ... cyan image forming unit 108: Image forming unit for black 109: Belt cleaning unit 109b Cleaning blade 201 Photoconductor belt (image carrier belt) 202 Steering drive roll (belt support member) 205 Development unit for yellow 206, magenta development unit, 207, cyan development unit, 208, black development unit, 209, belt cleaning unit, 209b, cleaning blade (cleaning member).

Claims (2)

An image carrier belt;
A frame for supporting the image carrier belt;
Belt support means supported movably with respect to the frame and supporting the image carrier belt;
A cleaning member for cleaning the surface of the image carrier belt;
An auger member for conveying the toner collected by the cleaning member;
A casing for holding the cleaning member and the auger member;
An interlocking mechanism disposed between the belt support means and the casing for maintaining a relative positional relationship between the belt support means and the cleaning member;
The image forming apparatus, wherein the casing is detachable from the frame while having the cleaning member and the auger member. The image forming apparatus according to claim 1, wherein the belt supporting member has a tension applying function for applying tension to the image carrier belt.

Images