JP2017045014A - Belt unit and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a belt unit capable of suppressing the enlargement and complication of a configuration for providing a grip part for holding the belt unit, when handling the belt unit and to provide an image forming apparatus.SOLUTION: A belt unit 70 includes a plurality of stretching rollers 71 to 75, an endless belt 7 which is an endless belt 7 stretched on the plurality of stretching rollers 71 to 75 and conveyed and to which a toner image is transferred from a plurality of image carriers 1Y to 1K, a switching mechanism 20 which is a switching mechanism 20 switching a first state where at least one of the plurality of image carriers 1Y to 1K is in contact with the belt 7 and a second state where all of the plurality of image carriers 1Y to 1K are separated from the belt 7 and includes a rotatable rotating shaft 21 and a moving member moved in synchronization with the rotation of the rotating shaft 21, and a grip part 78 for holding the belt unit 70, when handling the belt unit 70. A grip part 79 is configured so as to be connected to the rotating shaft 21.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a belt unit used in an image forming apparatus such as a copying machine, a printer, or a fax machine using an electrophotographic system or an electrostatic recording system, and an image forming apparatus including the belt unit.

  2. Description of the Related Art Conventionally, in an image forming apparatus using an electrophotographic method or an electrostatic recording method, an appropriate image is formed on a drum-shaped or belt-shaped electrophotographic photosensitive member (photosensitive member) or an image carrier that is an electrostatic recording dielectric. A toner image is formed in the process. The toner image is directly transferred to a recording material conveyed by a recording material carrier (direct transfer method), or is first transferred to an intermediate transfer member and then secondarily transferred to a recording material (intermediate transfer method). . An endless belt (hereinafter, also simply referred to as “belt”) is often used as a recording material carrier or an intermediate transfer member.

  As such an image forming apparatus, for example, there is a tandem type image forming apparatus that independently has an image forming section that forms an image with toner of each color of yellow, magenta, cyan, and black. As an example, a tandem-type electrophotographic image forming apparatus adopting an intermediate transfer system has an intermediate transfer belt that is an endless belt stretched around a plurality of stretching rollers as an intermediate transfer body, and this intermediate transfer belt A plurality of photoconductors are arranged side by side.

  In this type of image forming apparatus, an intermediate transfer unit including the intermediate transfer belt may be detachable from the apparatus main body in order to replace the intermediate transfer belt. The intermediate transfer unit may be provided with a handle for holding the intermediate transfer unit when the intermediate transfer unit is taken out from the apparatus main body.

  Patent Document 1 discloses a configuration in which a handle (handle) is provided on a frame at an end portion in the width direction of the intermediate transfer belt.

JP 2007-304482 A

  However, particularly in the configuration in which the intermediate transfer unit is moved in the width direction of the intermediate transfer belt and is attached to and detached from the apparatus main body, in order to hold the intermediate transfer unit in a balanced manner with both hands, It is desirable to provide a handle.

  In order to provide the grip portion near the center in the width direction of the intermediate transfer belt, it is conceivable to extend the attachment position of the handle portion to the frame at the end portion in the width direction of the intermediate transfer belt. Alternatively, a special stay member may be added between the frames at both ends in the width direction of the intermediate transfer belt in order to attach the grip portion. However, such a configuration leads to an increase in size and complexity of the configuration for providing the handle portion, which leads to an increase in cost.

  Accordingly, an object of the present invention is to provide a belt unit and an image forming apparatus capable of suppressing an increase in size and complexity of a configuration for providing a handle portion for holding the belt unit when the belt unit is handled. It is.

  The above object is achieved by the belt unit and the image forming apparatus according to the present invention. In summary, the present invention relates to a belt unit that can be attached to and detached from an apparatus main body of an image forming apparatus including a plurality of image carriers that carry toner images, and a plurality of tension rollers and a plurality of tension rollers. An endless belt that is conveyed in a stretched manner, and is endless to carry a recording material on which a toner image is transferred from the plurality of image carriers or to which a toner image is transferred from the plurality of image carriers. A first state in which at least one of the plurality of image carriers and the belt are in contact with each other, and a second state in which all of the plurality of image carriers and the belt are separated from each other. A switching mechanism comprising a pivotable pivot shaft and a moving member that moves in synchronism with the pivot of the pivot shaft; and the belt unit when the belt unit is handled. Handle for holding Has, the handle portion is a belt unit which is characterized in that it is connected to the pivot shaft.

  According to another aspect of the present invention, there is provided an image forming apparatus having an image carrier that carries a toner image and the belt unit of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the enlargement and complication of the structure for providing the handle part for hold | maintaining a belt unit when handling a belt unit can be suppressed.

It is a schematic sectional drawing of an image forming apparatus (all contact state). It is a schematic sectional drawing of an image forming apparatus (black contact state). It is a schematic sectional drawing of an image forming apparatus (all the separation state). It is a schematic diagram of the separation mechanism and the switching mechanism. FIG. 3 is a perspective view of an apparatus main body to which an intermediate transfer unit is attached. FIG. 6 is a side view and a cross-sectional view of an intermediate transfer unit (black contact state). FIG. 4 is a side view and a cross-sectional view of an intermediate transfer unit (fully spaced state). FIG. 3 is a perspective view of a state where an intermediate transfer unit is pulled out from the apparatus main body. FIG. 6 is a perspective view of the vicinity of a handle portion of an intermediate transfer unit. It is a schematic sectional drawing of the other example of an image forming apparatus.

  Hereinafter, a belt unit and an image forming apparatus according to the present invention will be described in more detail with reference to the drawings.

[Example 1]
1. 1 is a schematic cross-sectional view of an image forming apparatus 100 according to an embodiment of the present invention. The image forming apparatus 100 according to the present exemplary embodiment is a tandem type laser beam printer that employs an intermediate transfer method that can form a full-color image using an electrophotographic method. The image forming apparatus 100 forms an image on a recording material (recording medium, transfer material) P in accordance with an image signal sent from a computer or the like.

  The image forming apparatus 100 includes first, second, third, and fourth image forming units SY, SM, SC, and SK as a plurality of image forming units (stations). The first, second, third, and fourth image forming units SY, SM, SC, and SK form yellow (Y), magenta (M), cyan (C), and black (K) images, respectively.

  In this embodiment, the basic configuration and operation of the first, second, third, and fourth image forming units SY, SM, SC, and SK are different in the color of toner used in the developing process described later. Except for this, it is substantially the same. Therefore, hereinafter, unless there is a particular need for distinction, Y, M, C, and K at the end of a symbol representing an element for any color will be omitted, and the element will be described generally.

  The image forming unit S includes a photosensitive drum 1 that is a rotatable drum type electrophotographic photosensitive member (photosensitive member) as an image carrier. The photosensitive drum 1 is rotationally driven in the direction of arrow R1 in the figure. In the image forming unit S, the following process devices are sequentially arranged around the photosensitive drum 1 in the rotation direction. First, a charging roller 2 that is a roller-type charging member as a charging unit is disposed. Next, an exposure device (laser scanner) 3 as an exposure unit is arranged. Next, a developing device 4 as a developing unit is arranged. Next, a primary transfer roller 5 that is a roller-type primary transfer member as a primary transfer means is disposed. Next, a drum cleaner 6 as a photosensitive member cleaning means is disposed. The exposure apparatus 3 is configured as a single unit that can expose the photosensitive drums 1Y, 1M, 1C, and 1K of the image forming units SY, SM, SC, and SK.

  The surface of the rotating photosensitive drum 1 is charged almost uniformly by a charging roller 2 to a predetermined potential having a predetermined polarity (negative polarity in this embodiment). The surface of the charged photosensitive drum 1 is exposed by the exposure device 3 based on the input image information signal, and an electrostatic latent image (electrostatic image) is formed on the photosensitive drum 1. The electrostatic latent image formed on the photosensitive drum 1 is developed by the developing device 4 using toner as a developer, and a toner image is formed on the photosensitive drum 1. In this embodiment, a toner image is formed by image part exposure and reversal development. That is, the exposed portion on the photosensitive drum 1 where the absolute value of the potential is lowered by being exposed after being uniformly charged is charged to the same polarity (negative polarity in this embodiment) as the charging polarity of the photosensitive drum 1. Adhered toner adheres.

  The image forming apparatus 100 includes an intermediate transfer unit 70 disposed to face the image forming units SY, SM, SC, and SK. The intermediate transfer unit 70 includes an intermediate transfer belt 7 constituted by a rotatable endless belt as an intermediate transfer member. The intermediate transfer belt 7 is stretched around a driving roller 71, a tension roller 72, an upstream auxiliary roller 73, a downstream auxiliary roller 74, and a secondary transfer counter roller 75 as a plurality of stretching rollers (support rollers). The intermediate transfer belt 7 rotates (circulates) in the direction of arrow R2 in the drawing when the driving roller 71 is driven to rotate. On the inner peripheral surface (back surface) side of the intermediate transfer belt 7, the primary transfer rollers 5Y, 5M, 5C, and 5K described above are disposed to face the photosensitive drums 1Y, 1M, 1C, and 1K. The primary transfer roller 5 is urged (pressed) toward the photosensitive drum 1 via the intermediate transfer belt 7 to form a primary transfer portion (primary transfer nip) N1 where the photosensitive drum 1 and the intermediate transfer belt 7 are in contact with each other. . On the outer peripheral surface (front surface) side of the intermediate transfer belt 7, a secondary transfer roller which is a roller-type secondary transfer member serving as a secondary transfer unit is opposed to the secondary transfer counter roller (secondary transfer inner roller) 75. (Secondary transfer outer roller) 8 is arranged. The secondary transfer roller 8 is urged (pressed) toward the secondary transfer counter roller 75 via the intermediate transfer belt 7, and a secondary transfer portion (secondary transfer portion) where the intermediate transfer belt 7 and the secondary transfer roller 8 come into contact with each other. (Next transfer nip) N2 is formed. Further, on the outer peripheral surface side of the intermediate transfer belt 7, a belt cleaner 77 is disposed as an intermediate transfer member cleaning unit so as to face the driving roller 71. The intermediate transfer unit 70 will be described in detail later.

  The toner image formed on the photosensitive drum 1 as described above is rotated at the primary transfer portion N1 by the predetermined pressure and electrostatic load bias applied by the primary transfer roller 5 at the intermediate transfer belt 7 that is rotating. Transferred (primary transfer) on top. For example, when forming a full-color image, toner images of each color of yellow, magenta, cyan, and black formed on the photosensitive drums 1Y, 1M, 1C, and 1K are transferred so as to be sequentially superimposed on the intermediate transfer belt 7. . In this case, the image forming process of each color processed in parallel by each image forming unit S is performed at a timing of superimposing on the toner image transferred onto the intermediate transfer belt 7 by the upstream primary transfer unit N1. As a result, a multiple toner image for a full color image is formed on the intermediate transfer belt 7. The toner remaining on the photosensitive drum 1 after the primary transfer process (primary transfer residual toner) is removed from the photosensitive drum 1 by the drum cleaner 6 and collected.

  The toner image on the intermediate transfer belt 7 is transferred between the intermediate transfer belt 7 and the secondary transfer roller 8 by the predetermined pressure and electrostatic load bias applied by the secondary transfer roller 8 in the secondary transfer portion N2. Is transferred (secondary transfer) onto the recording material P that is nipped and conveyed. The recording material P is supplied to the secondary transfer portion N2 by the feeding device 9 in accordance with the timing at which the toner image on the intermediate transfer belt 7 is conveyed to the secondary transfer portion N2. The toner remaining on the intermediate transfer belt 7 after the secondary transfer process (secondary transfer residual toner) is removed from the intermediate transfer belt 7 by the belt cleaner 77 and collected.

  The recording material P onto which the toner image has been transferred is conveyed to a fixing device 10 as a fixing unit. The fixing device 10 melts and fixes the toner image on the recording material P by applying a predetermined pressure and heat to the recording material P in a fixing nip formed by the opposing fixing roller 10a and pressure roller 10b. The recording material P on which the toner image is fixed is then discharged (output) to the outside of the apparatus main body 110 of the image forming apparatus 100.

  In this embodiment, in each image forming unit S, the photosensitive drum 1 and the charging roller 2, the developing device 4, and the drum cleaner 6 as process means acting on the photosensitive drum 1 can be integrally attached to and detached from the apparatus main body 110. A simple process cartridge 11 is configured.

2. Intermediate Transfer Unit Next, the basic configuration and operation of the intermediate transfer unit 70 in this embodiment will be described in more detail. In this embodiment, the intermediate transfer unit 70 includes an intermediate transfer belt 7, stretching rollers 71 to 75 of the intermediate transfer belt 7, primary transfer rollers 5Y, 5M, 5C, and 5K, a belt cleaner 77, and the like. ing. The intermediate transfer unit 70 can be attached to and detached from the apparatus main body 110.

  Here, the direction (width direction) substantially orthogonal to the moving direction of the intermediate transfer belt 7 is also referred to as “thrust direction”. This thrust direction is substantially parallel to the rotational axis direction of the photosensitive drum 1 and the stretching rollers 71 to 75. Further, regarding the image forming apparatus 100, the front side in FIG. 1 in the thrust direction is referred to as “front side”, and the back side in FIG. 1 is referred to as “back side”. Further, with respect to the image forming apparatus 100, the vertical direction refers to the vertical direction in the vertical direction, but does not mean just above or directly below, but above the horizontal with respect to a reference position or element, It also includes being below. Note that the positional relationship of the positions or elements in the image forming apparatus 100 refers to the positional relationship when the image forming apparatus 100 is disposed in a normally used posture.

  The four photosensitive drums 1Y, 1M, 1C, and 1K are arranged substantially linearly along the moving direction of the intermediate transfer belt 7. In this embodiment, the arrangement direction of the four photosensitive drums 1Y, 1M, 1C, and 1K is a substantially horizontal direction. More specifically, in the present embodiment, the four photosensitive drums 1Y, 1M, 1C, and 1K are arranged in a substantially straight line so that the common tangent line on all the intermediate transfer units 70 side is substantially horizontal. ing. Here, the arrangement direction of the four photosensitive drums 1Y, 1M, 1C, and 1K is also referred to as “drum arrangement direction”.

  The intermediate transfer unit 70 includes an intermediate transfer belt 7. The intermediate transfer belt 7 is stretched around a driving roller 71, a tension roller 72, an upstream auxiliary roller 73, a downstream auxiliary roller 74, and a driving roller 75 as a plurality of stretching rollers (support rollers). The intermediate transfer belt 7 is arranged along the drum arrangement direction, and is long in one direction along the drum arrangement direction in a state of being stretched by a plurality of stretching rollers 71 to 75 (the outer dimension in the horizontal direction is vertical). Rotate on the transport trajectory (longer than the outer dimension in the direction). The driving roller 71 transmits a rotational driving force from a driving motor 80 (such as FIG. 5) serving as a driving means to the intermediate transfer belt 7 to rotate (move and convey) the intermediate transfer belt 7 in the direction of arrow R2. The tension roller 72 is urged from the inner peripheral surface side to the outer peripheral surface side of the intermediate transfer belt 7 by a tension spring 76 as an urging unit (tension applying unit), and applies tension to the intermediate transfer belt 7. The upstream auxiliary roller 73 and the downstream auxiliary roller 74 support the intermediate transfer belt 7 on the upstream side and the downstream side of the four photosensitive drums 1Y to 1K in the rotation direction of the intermediate transfer belt 7, respectively. A surface (image transfer surface) stretched opposite to 1K is formed. The secondary transfer counter roller 75 sandwiches the intermediate transfer belt 7 with the secondary transfer roller 8 to form a secondary transfer portion N2.

The material of the intermediate transfer belt 7 uses a resin having relatively high rigidity such as PVDF (polyvinylidene fluoride), polyamide, polyimide, PET (polyethylene terephthalate), and polycarbonate in order to suppress the generation of wrinkles during rotational driving. It is desirable. Further, if the thickness of the intermediate transfer belt 7 is too thin, there is a concern that sufficient durability due to wear may not be obtained. There is a concern that dents and folds may occur without bending. Therefore, the thickness of the intermediate transfer belt 7 is desirably in the range of 0.02 mm to 0.50 mm. In this embodiment, a resin belt having a polyimide base layer is used as the intermediate transfer belt 7. This intermediate transfer belt 7 has a tensile elastic modulus E = 18000 N / cm ² and a film thickness of 0.08 mm.

  In the present embodiment, the belt cleaner 77 has a cleaning blade 77 a made of urethane rubber and disposed so as to contact the intermediate transfer belt 7 at a position facing the driving roller 71. The cleaning blade 77 a is arranged in the counter direction with respect to the moving direction of the intermediate transfer belt 7. The cleaning blade 77a is set at a set angle (angle formed by a tangent to the intermediate transfer belt 7 at the contact portion) of 25 °, a contact pressure of 30 gf / cm, and a urethane rubber hardness of 75 ° in JIS-A hardness. The thickness of the urethane rubber is 2 mm.

3. Next, the contact / separation state (separation state) between the photosensitive drum 1 and the intermediate transfer belt 7 will be described.

  The image forming apparatus 100 according to the present exemplary embodiment can execute an image forming operation in a full color mode in which all the image forming units SY, SM, SC, and SK can form images and form full color images. In addition, the image forming apparatus 100 according to the present exemplary embodiment can execute an image forming operation in a monochrome mode in which an image is formed only in the black image forming unit SK to form a black monochrome image. When the full color mode is executed, the photosensitive drum 1 and the intermediate transfer belt 7 are brought into contact with each other in all the image forming units SY, SM, SC, and SK. When the monochrome mode is executed, the intermediate transfer belt 7 is separated from the photosensitive drum 1 in the image forming portions SY, SM, and SC for yellow, magenta, and cyan that are not used for image formation. This is because the wear of the photosensitive drums 1Y, 1M, and 1C for the respective colors of yellow, magenta, and cyan and the intermediate transfer belt 7 is reduced, thereby extending their life. In this embodiment, the intermediate transfer belt 7 can be separated from the photosensitive drum 1 in all the image forming units SY, SM, SC, and SK. This is because when the intermediate transfer unit 70 and the photosensitive drum 1 (process cartridge 11) are attached to and detached from the apparatus main body 110, the intermediate transfer belt 7 and the photosensitive drum 1 are rubbed and scratched on their surfaces. This is to suppress this.

  As described above, the image forming apparatus 100 according to the present exemplary embodiment can switch the contact / separation state between the photosensitive drum 1 and the intermediate transfer belt 7 to the following states. First, the intermediate transfer belt 7 is in contact with all the photosensitive drums 1Y, 1M, 1C, and 1K (hereinafter referred to as “all contact state”). Second, the intermediate transfer belt 7 is in contact with only the black photosensitive drum 1K (hereinafter also referred to as “black contact state”). Third, the intermediate transfer belt 7 is separated from all the photosensitive drums 1Y, 1M, 1C, and 1K (hereinafter, also referred to as “totally separated state”). In the present embodiment, as described below, the above-described separation / contact states are switched by changing the arrangement of the primary transfer rollers 5Y, 5M, 5C, and 5K, the upstream auxiliary roller 73, and the downstream auxiliary roller 74. .

  1, 2, and 3 are schematic cross-sectional views of the image forming apparatus 100 in the full contact state, the black contact state, and the full separation state, respectively. FIG. 4 is a schematic diagram showing elements relating to an operation for switching the contact state between the photosensitive drum 1 and the intermediate transfer belt 7.

  In the full contact state shown in FIG. 1, all the primary transfer rollers 5Y, 5M, 5C, and 5K are in positions (contact positions) that contact the corresponding photosensitive drums 1Y, 1M, 1C, and 1K via the intermediate transfer belt 7. Be placed. In the full contact state, the upstream auxiliary roller 73 and the downstream auxiliary roller 74 are arranged on a common tangent line of all the photosensitive drums 1Y, 1M, 1C, and 1K. As a result, the intermediate transfer belt 7 is brought into contact with all the photosensitive drums 1Y, 1M, 1C, and 1K. In the full contact state, the secondary transfer counter roller 75 is brought into contact with the secondary transfer roller 8 via the intermediate transfer belt 7.

  In the black contact state shown in FIG. 2, the primary transfer rollers 5Y, 5M, and 5C for yellow, magenta, and cyan colors are moved upward and are separated from the corresponding photosensitive drums 1Y, 1M, and 1C ( (Spaced position). At this time, in this embodiment, the primary transfer rollers 5Y, 5M, and 5C for yellow, magenta, and cyan are separated from the intermediate transfer belt 7. Further, in the black contact state, the upstream auxiliary roller 73 is moved upward and disposed at a position away from the common tangent line of all the photosensitive drums 1Y, 1M, 1C, and 1K. At this time, in this embodiment, the upstream auxiliary roller 73 is separated from the intermediate transfer belt 7. On the other hand, in the black contact state, the primary transfer roller 5K for black is disposed at a position (contact position) that contacts the corresponding photosensitive drum 1K via the intermediate transfer belt 7. Further, the downstream auxiliary roller 74 is disposed on a common tangent line of all the photosensitive drums 1Y, 1M, 1C, and 1K. Accordingly, the intermediate transfer belt 7 is separated from the photosensitive drums 1Y, 1M, and 1C for yellow, magenta, and cyan. In the black contact state, the secondary transfer counter roller 75 is brought into contact with the secondary transfer roller 8 via the intermediate transfer belt 7. The extra length of the intermediate transfer belt 7 generated by the movement of the roller is absorbed by the tension roller 72 moving in the arrow W direction (tension direction) in FIG.

  In the fully separated state shown in FIG. 3, all the primary transfer rollers 5Y, 5M, 5C, and 5K are moved upward and separated from the corresponding photosensitive drums 1Y, 1M, 1C, and 1K (separated positions). Placed in. At this time, in this embodiment, the primary transfer rollers 5Y, 5M, and 5C for the respective colors of yellow, magenta, and cyan are separated from the intermediate transfer belt 7, but the primary transfer roller 5K for black contacts the intermediate transfer belt 7. doing. Further, in the fully separated state, the upstream auxiliary roller 73 and the downstream auxiliary roller 74 are moved upward and are disposed at positions away from the common tangent line of all the photosensitive drums 1Y, 1M, 1C, and 1K. At this time, in this embodiment, the upstream auxiliary roller 73 is separated from the intermediate transfer belt 7, but the downstream auxiliary roller 74 is in contact with the intermediate transfer belt 7. As a result, the intermediate transfer belt 7 is separated from all the photosensitive drums 1Y, 1M, 1C, and 1K. In this embodiment, the secondary transfer counter roller 75 is separated from the secondary transfer roller 8 in the fully separated state.

  In this embodiment, the primary transfer roller 5 that is separated from the photosensitive drums 1 for yellow, magenta, and cyan colors is also separated from the intermediate transfer belt 7 in the black contact state or the completely separated state. As a result, it is easy to ensure the amount of separation of the intermediate transfer belt 7 from the photosensitive drum 1. However, the present invention is not limited to this, and these primary transfer rollers 5 may be in contact with the intermediate transfer belt 7 when separated from the photosensitive drum 1.

  In this embodiment, as shown in FIG. 4, the primary transfer rollers 5Y, 5M, and 5C of yellow, magenta, and cyan are moved by a separation / contact mechanism 30 as a separation / contact means. In this embodiment, the upstream auxiliary roller 73 is moved by the upstream auxiliary roller moving mechanism 40 as the upstream auxiliary roller moving means. The operations of the separation / contact mechanism 30 and the upstream auxiliary roller moving mechanism 40 are controlled by a CPU 50 as a control unit provided in the apparatus main body 110. As the separation / contact mechanism 30, an available one can be arbitrarily used. For example, a moving member that moves the bearing member of the primary transfer roller 5 in a direction toward or away from the photosensitive drum 1 can be provided, and the moving member can be operated by a driving force from a driving motor controlled by the CPU 50. Similarly, the upstream auxiliary roller moving mechanism 40 can be arbitrarily used. For example, a moving member for moving the bearing member of the upstream auxiliary roller 73 in a direction approaching or moving away from the common tangent of the photosensitive drum 1 is provided, and the moving member is operated by a driving force from a driving motor controlled by the CPU 50. Can be made. A part of the configuration of the separation / contact mechanism 30 and the upstream auxiliary roller moving mechanism 40 may be shared.

  On the other hand, in this embodiment, the primary transfer roller 5K for black is moved by a switching mechanism 20 as a switching unit. In this embodiment, the switching mechanism 20 moves the black primary transfer roller 5K and also moves the downstream auxiliary roller 74 and the secondary transfer counter roller 75. The switching mechanism 20 operates when operated by an operator as will be described in detail later. The configuration and operation of the switching mechanism 20 will be described in detail later.

  As described above, in this embodiment, the intermediate transfer unit 70 includes the separation / contact mechanism 30, the upstream auxiliary roller moving mechanism 40, and the switching mechanism 20 in order to change the separation / contact state between the photosensitive drum 1 and the intermediate transfer belt 7. Have. The separation / contact mechanism 30 moves a transfer member corresponding to an image carrier other than the image carrier most downstream in the belt conveyance direction among the plurality of image carriers, to the next first position, to the second position, It is an example of the mechanism made to move between. The first position is a position in contact with the corresponding image carrier via the belt. The second position is a position farther from the corresponding image carrier than the first position where the belt is separated from the corresponding image carrier. The switching mechanism 20 includes a first state in which at least one of the plurality of image carriers is in contact with the belt, and a second state in which all of the image carriers are separated from the belt. It is an example of a mechanism for switching between. In particular, in this embodiment, the switching mechanism 20 moves the transfer member corresponding to the most downstream image carrier between the next third position and the fourth position. The third position is a position in contact with the most downstream image carrier via the belt. The fourth position is a position away from the most downstream image carrier than the third position, where the belt is separated from the most downstream image carrier.

4). Next, a procedure for taking out the intermediate transfer unit 70 from the switching mechanism 20 and the apparatus main body 110 will be described with reference to FIGS. FIG. 5 is a perspective view of the state in which the intermediate transfer unit 70 is set (mounted) on the apparatus main body 110 as viewed from the front side. In FIG. 5, many other elements provided in the apparatus main body 110 are omitted so that the intermediate transfer unit 70 can be seen. FIG. 6A is a front view of the intermediate transfer unit 70 in a black contact state, and FIG. 6B is a cross-sectional view thereof. FIG. 7A is a front view of the intermediate transfer unit 70 in the fully separated state, and FIG. 7B is a cross-sectional view thereof. 6 and 7 also show the photosensitive drum 1 together with the intermediate transfer unit 70. FIG. 8 is a perspective view of the state where the intermediate transfer unit 70 is pulled out from the apparatus main body 110 as viewed from the front side (the illustration of many elements is omitted as in FIG. 5).

  First, the switching mechanism 20 will be described. In this embodiment, the switching mechanism 20 is configured so that only the black photosensitive drum 1 and the intermediate transfer belt 7 are in contact with each other and the black contact state (first state) and all the photosensitive drums 1 and the intermediate transfer belt 7 are separated from each other. The completely separated state (second state) is switched. In other words, the switching mechanism 20 changes the posture of the intermediate transfer belt 7 when viewed in the width direction of the intermediate transfer belt 7.

  As shown in FIGS. 5 and 6A and 6B, in this embodiment, the intermediate transfer unit 70 supports the first frame (inner frame) 78a and the first frame 78a in a rotatable manner. A second frame (outer frame) 78b and a belt cleaner frame 78c. The outer frame 78 b has front and back side portions 78 b 1 and 78 b 2 provided at both ends in the width direction of the intermediate transfer belt 7. The belt cleaner frame 78c is disposed to face the drive roller 71 so as to connect the front and back side portions 78b1 and 78b2 of the outer frame 78b. An inner frame 78a is disposed inside a region defined by the outer frame 78b and the belt cleaner frame 78c. The inner frame 78a supports a plurality of stretching rollers 71 to 75 that stretch the intermediate transfer belt 7, the primary transfer roller 5, and the like. The inner frame 78a is located with respect to the outer frame 78b around a frame rotation shaft (not shown) disposed upstream of the plurality of photosensitive drums 1 in the moving direction of the image transfer surface of the intermediate transfer belt 7. It can be turned.

  In this embodiment, the switching mechanism 20 rotates the inner frame 78a upward when switching from the black contact state (FIGS. 2 and 6) to the fully separated state (FIGS. 3 and 7). As a result, the switching mechanism 20 moves (rotates) the black primary transfer roller 5K, the downstream auxiliary roller 74, and the secondary transfer counter roller 75 together with the inner frame 78a, so that the fully separated state as described above is achieved. To do.

  More specifically, the switching mechanism 20 includes a rotation shaft 21 rotatably supported on the outer frame 78b, a moving member 22 attached to the rotation shaft 21, and a guide pin 23 provided on the inner frame 78a. And a handle 24 attached to the rotating shaft 21.

  The rotating shaft 21 is passed between the front side portion 78b1 and the back side portion 78b2 of the outer frame 78b and extends in the thrust direction. The rotation shaft 21 is disposed above the intermediate transfer belt 7 at a position closest to the black primary transfer roller 5K among the plurality of primary transfer rollers 5 in the moving direction of the image transfer surface of the intermediate transfer belt 7. Has been. The moving member 22 is a substantially plate-like link member, and is disposed along the inner side surfaces of the front and back side portions 78b1 and 78b2 of the outer frame 78b (only the front side is shown in FIGS. 6 and 7). ). The moving member 22 is fixed to the rotation shaft 21 at one corner, and rotates in the same direction in synchronization with the rotation of the rotation shaft 21. The moving member 22 is provided with a guide portion (guide long hole) 22 a in which the distance from the rotation shaft 21 gradually changes in the rotation direction around the rotation shaft 21. The guide pin 23 as the engaging portion is a substantially cylindrical protrusion, and is provided so as to protrude from the outer surface of the inner frame 78a facing the front side and the rear side portions 78b1 and 78b2 of the outer frame 78b. (Only the front side is shown in FIGS. 6 and 7). The guide pin 23 is engaged with the guide portion 22a of the moving member 22 so as to be capable of relative movement (sliding movement). The handle 24 as an operation portion is fixed to the rotating shaft 21 outside the side portion 78b1 on the front side of the outer frame 78b. In this embodiment, the intermediate transfer unit 70 is disposed above the plurality of photosensitive drums 1Y, 1M, 1C, and 1K when mounted on the apparatus main body 110, and the rotating shaft 21 is located above the intermediate transfer belt 7. Is arranged.

  Next, a procedure for taking out the intermediate transfer unit 70 from the apparatus main body 110 will be described. As shown in FIG. 5, with the intermediate transfer unit 70 set in the apparatus main body 110, the intermediate transfer belt 7 moves in the direction of the arrow R2 in the drawing, and image formation is performed. Further, when the intermediate transfer unit 70 is taken out from the apparatus main body 110, the intermediate transfer unit 70 is moved in the arrow X direction in the drawing, which is substantially orthogonal to the moving direction (conveying direction) indicated by the arrow R2 in the drawing of the intermediate transfer belt 7. Remove to the front. When the intermediate transfer unit 70 is taken out from the apparatus main body 110, the front side portion of the intermediate transfer unit 70 is exposed by opening a door (not shown) provided on the exterior cover of the apparatus main body 110.

  In this embodiment, as shown in FIG. 6, when the operator accesses the intermediate transfer unit 70 in order to remove the intermediate transfer unit 70 from the apparatus main body 110, the photosensitive drum 1 and the intermediate transfer belt 7 are separated. The contact state is a black contact state. Then, before pulling out the intermediate transfer unit 70 from the apparatus main body 110, the operator operates the switching mechanism 20 to change the contact state between the photosensitive drum 1 and the intermediate transfer belt 7 to the black contact state as shown in FIG. To the fully separated state.

  In order to switch from the black contact state to the fully separated state, the operator rotates the handle 24 from the state of FIG. 6 by about 90 degrees counterclockwise in the drawing to the state of FIG. When the handle 24 is rotated, the rotation shaft 21 fixed to the handle 24 and the moving member 22 fixed to the rotation shaft 21 rotate in the same direction as the handle 24 in synchronization. When the moving member 22 rotates, the guide pin 23 moves along the guide portion 22a of the moving member 22 while reducing the distance from the rotating shaft 21. That is, the moving member 22 pulls up the inner frame 78a via the guide pin 23 engaged with the guide portion 22a. As a result, the inner frame 78 a rotates upward with respect to the outer frame 78 b and moves in a direction away from the photosensitive drum 1. Thus, the primary transfer roller 5K for black supported by the inner frame 78a is separated from the photosensitive drum 1 for black and is in a fully separated state. At this time, the downstream auxiliary roller 74 and the secondary transfer counter roller 75 supported by the inner frame 78a move together with the black primary transfer roller 5K, so that the secondary transfer counter roller 75 is separated from the secondary transfer roller 8. (FIG. 3).

  As shown in FIG. 8, when the intermediate transfer unit 70 is pulled out from the apparatus main body 110, the two fixing screws 60 for fixing the intermediate transfer unit 70 to the apparatus main body 110 are removed. Then, after rotating the handle 24 as described above, the intermediate transfer unit 70 is pulled out in the direction of the arrow X in the figure. At this time, the operator can start pulling out the intermediate transfer unit 70 by first grasping the outer frame 78b. As shown in FIG. 8, with the intermediate transfer unit 70 pulled out approximately halfway to the outside of the apparatus main body 110, the operator is provided on the handle 79 described later in detail and on the outer surface of the belt cleaner frame 78c. Change to the holding portion 78c1. Thereafter, the operator can completely pull out the intermediate transfer unit 70 from the apparatus main body 110 and hold it as it is.

  When the intermediate transfer unit 70 is set in the apparatus main body 110, the work may be performed in the reverse order of the above-described take-out procedure.

  The handle portion 79 is used in a state in which the intermediate transfer unit 70 is detached from the apparatus main body 110, and a part or all of the intermediate transfer unit 70 is inside the apparatus main body 110 and performs an operation of taking out or mounting. It may be used at times. That is, the gripping portion 79 is used for holding the intermediate transfer belt 70 when the intermediate transfer unit 70 is handled.

5). Next, the handle 79 for holding the intermediate transfer unit 70 will be described in more detail.

  As described above, in this embodiment, the four photosensitive drums 1 for each of the colors yellow, magenta, cyan, and black are arranged from the upstream side to the downstream side in the moving direction of the image transfer surface of the intermediate transfer belt 7 that faces the photosensitive drums 1. Arranged in this order. As shown in FIG. 6, in the black contact state, the black photosensitive drum 1 </ b> K disposed on the most downstream side in the moving direction of the image transfer surface of the intermediate transfer belt 7 and the intermediate transfer belt 7 are in contact with each other. . In switching between the black contact state and the fully separated state, it is necessary to move the black primary transfer roller 5K facing the black photosensitive drum 1K. Therefore, the rotation shaft 21 and the moving member 22 of the switching mechanism 20 are disposed at a position close to the primary transfer roller 5K for black in the moving direction of the image transfer surface of the intermediate transfer belt 7.

  FIG. 9 is an enlarged perspective view of the periphery of the handle portion 79. The handle portion 79 is connected to the rotation shaft 21 of the switching mechanism 20 and is supported by the rotation shaft 21 so as to be rotatable around the rotation shaft 21. More specifically, the handle portion 79 includes a main portion 79a that is separated from the rotation shaft 21 and extends substantially parallel to the rotation shaft 21, and an axial line of the main portion 79a from both ends in the axial direction of the main portion 79a. And connecting portions 79b and 79b extending toward the rotation shaft 21 in a substantially orthogonal direction. And the edge part on the opposite side to the main part 79a of each connection part 79b and 79b is connected with the rotating shaft 21 rotatably. The front connection portion 79b is provided with a rotation stop portion 79c that can engage with the outer frame 78b. The operator can hold the intermediate transfer unit 70 by gripping the main portion 79 a of the handle portion 79. Note that the shape of the handle 79 is not limited to that of the present embodiment, and it is sufficient that the intermediate transfer unit 70 can be held.

  FIG. 9A shows a state of the handle 79 when the intermediate transfer unit 70 is set on the apparatus main body 110. In this state, the handle 79 is tilted to the side along the surface of the intermediate transfer belt 7, and is stationary at a position where the rotation stopper 79 c provided on the handle 79 contacts the outer frame 78. As a result, in the apparatus main body 110, the handle portion 79 is accommodated almost inside the outer shape of the intermediate transfer unit 70 without taking a space. FIG. 9B shows a state of the handle 79 when the intermediate transfer unit 70 is taken out from the apparatus main body 110. In this state, the handle 79 protrudes outward from the intermediate transfer unit 70 in order to hold the intermediate transfer unit 70. That is, the handle 79 is turned about 90 ° from the state shown in FIG. 9A around the turning shaft 21 to the state shown in FIG. 9B and is held.

  In this embodiment, the rotation shaft 21 is a round bar. However, the shape of the rotation shaft 21 is not limited as long as it can rotate. In addition to a round bar (solid or hollow), a square axis (may be solid or hollow), a sheet metal is bent and a desired cross-sectional shape (circular, polygonal (for example, square), some of which are missing. Any shape can be used, such as a solid shape (for example, a U-shape).

  Thus, in the present embodiment, the handle portion 79 is connected to the rotating shaft 21 of the switching mechanism 20. Accordingly, the attachment position of the handle portion 79 is not extended to the frame at the end in the width direction of the intermediate transfer belt 7 or a stay member is not added between the frames in order to provide the handle portion 79. The transfer unit 70 can be held with good balance. Therefore, an increase in size and complexity of the configuration for providing the handle 79 can be suppressed, and an increase in cost can be suppressed.

  In this embodiment, as described above, the black photosensitive drum 1K is arranged on the most downstream side in the moving direction of the image transfer surface of the intermediate transfer belt 7, and the rotation shaft 21 of the switching mechanism 20 is also arranged in the vicinity thereof. ing. Therefore, the rotating shaft 21 and the handle 79 attached thereto are located away from the center of gravity of the intermediate transfer unit 70 (G in FIG. 8) on the side where the black photosensitive drum 1K is located. . In other words, in this embodiment, the rotating shaft 21 and the handle 79 attached thereto are provided downstream of the center of gravity of the intermediate transfer unit 70 in the moving direction of the image transfer surface of the intermediate transfer belt 7. Yes. In this embodiment, the center of gravity of the intermediate transfer unit 70 is located slightly closer to the center than the photosensitive drum 1Y for yellow in the moving direction of the image transfer surface of the intermediate transfer belt 7. On the other hand, the holding portion 78c1 is provided on the belt cleaner frame 78c, and is located away from the center of gravity of the intermediate transfer unit 70 on the side where the most upstream yellow photosensitive drum 1Y is located. That is, in the present embodiment, the holding portion 78 c 1 is provided on the upstream side, which is the opposite side of the rotational shaft 21 with respect to the center of gravity position of the intermediate transfer unit 70 in the moving direction of the image transfer surface of the intermediate transfer belt 7. Yes. As a result, when the holding portion 78c1 provided on the yellow photosensitive drum 1Y side is held by one hand, the grip portion 79 provided on the black photosensitive drum 1K side by the other hand is more balanced. Can be held.

  In this embodiment, the handle 79 is provided at a position overlapping the intermediate transfer belt 7 in a direction (width direction) substantially orthogonal to the moving direction of the image transfer surface of the intermediate transfer belt 7. In particular, in this embodiment, the grip portion 79 is in the direction (width direction) substantially orthogonal to the moving direction of the image transfer surface of the intermediate transfer belt 7 with respect to the center of the intermediate transfer belt 7 (L in FIG. 8). The center of gravity of the intermediate transfer unit 70 (G in FIG. 8) is provided at a position shifted to a certain side. In this embodiment, a drive motor 80 for driving the drive roller 71 is attached to the inner frame 78 a, and the center of gravity of the intermediate transfer unit 70 is in front of the center in the width direction of the intermediate transfer belt 7. For this reason, in this embodiment, the handle portion 79 is provided at a position shifted forward from the center of the intermediate transfer belt 7 in the width direction of the intermediate transfer belt 7. Similarly, the holding portion 78 c 1 is also provided at a position shifted forward from the center of the intermediate transfer belt 7 in the width direction of the intermediate transfer belt 7. As a result, the intermediate transfer unit 70 can be held by the grip portion 79 and the holding portion 78c1 with good balance.

  As described above, according to the present embodiment, the handle 79 is connected to the rotating shaft 21 so that the handle 79 for holding the intermediate transfer unit 70 when the intermediate transfer unit 70 is handled has a large size. And complications can be suppressed.

[Others]
As mentioned above, although this invention was demonstrated according to the specific Example, this invention is not limited to the above-mentioned Example.

  In the above-described embodiment, the number of image forming units is four. However, the number of image forming units is not limited to this, and may be more or less. Further, the arrangement order of the image forming units for each color is not limited to that in the above-described embodiment.

  In the above-described embodiment, the intermediate transfer belt is stretched by the five stretch rollers, but the number of stretch rollers for stretching the intermediate transfer belt is not limited to this, and more Or less.

  In the above-described embodiment, the switching mechanism is configured to switch between the black contact state and the fully separated state by rotating the inner frame that supports the stretching roller, the primary transfer roller, and the like with respect to the outer frame. However, the present invention is not limited to such a configuration. A specific configuration of the switching mechanism is arbitrary as long as the handle portion can be connected to the rotation shaft provided in the switching mechanism. For example, the moving member that rotates in synchronization with the rotation shaft of the switching mechanism may directly move the bearing member of the primary transfer roller.

  In the above-described embodiment, the moving member is directly fixed to the rotating member and is configured to rotate in synchronization with the rotating shaft. However, the present invention is not limited to this. The moving member may be rotated in synchronization with the rotating shaft by transmitting the rotational force of the rotating shaft through a transmission member such as a gear. Further, the moving member is not limited to rotating in synchronization with the rotating member, but is moved in synchronization with the rotating shaft so that the photosensitive drum and the intermediate transfer belt are separated from each other (intermediate transfer belt). Any device can be used as long as the posture of the belt can be switched. For example, the moving member may be a link member that linearly moves (reciprocates) when the rotational force of the rotation shaft is transmitted directly or via a transmission member such as a gear. The link member may move the frame or the bearing member of the primary transfer roller so that the contact state (intermediate transfer belt posture) between the photosensitive drum and the intermediate transfer belt may be switched.

  In the above-described embodiment, the switching mechanism is configured to rotate the rotation shaft by manually rotating the handle, but is not limited thereto. For example, the switching mechanism may have a drive source such as a motor, and may automatically switch the contact state (intermediate transfer belt posture) between the photosensitive drum and the intermediate transfer belt.

  Further, in the above-described embodiment, the black photosensitive drum is disposed on the most downstream side in the moving direction of the image transfer surface of the intermediate transfer belt, and the rotation shaft and the grip portion are on the downstream side of the center of gravity position of the intermediate transfer unit. However, the present invention is not limited to this. For example, when the black photosensitive drum is arranged at the uppermost position in the moving direction of the image transfer surface of the intermediate transfer belt, the rotation shaft and the handle are arranged upstream of the center of gravity of the intermediate transfer unit. May be. In this case, a holding unit similar to that in the above-described embodiment can be arranged downstream of the center of gravity position of the intermediate transfer unit. Furthermore, the present invention is not limited to a configuration in which the grip portion is disposed on the upstream side or the downstream side of the center of gravity position of the intermediate transfer unit in the moving direction of the image transfer surface of the intermediate transfer belt. For example, a configuration in which the grip portion is arranged at substantially the same position as the center of gravity in the moving direction of the image transfer surface of the intermediate transfer belt can be contemplated. Further, depending on the position of the handle portion or the like, the holding portion in the above-described embodiment may not be provided.

  In the above-described embodiments, the grip portion is provided so as to be shifted to the near side from the center in the width direction of the intermediate transfer belt. It does not have to be misaligned.

  In the above-described embodiment, the switching mechanism is configured to switch between the black contact state as the first state and the fully separated state as the second state. However, the present invention has such a configuration. It is not limited to. For example, the switching mechanism may be configured to switch between the all contact state as the first state and the all separation state as the second state. In addition, the switching mechanism includes a second total distance in which the distance between at least one photosensitive drum and the belt is longer than that in the first total separated state as the first state and the first total separated state as the second state. You may be comprised so that a separation state may be switched.

  In the above-described embodiments, the intermediate transfer type image forming apparatus has been described as an example, but the present invention can also be applied to a direct transfer type image forming apparatus. FIG. 10 is a schematic cross-sectional view of a main part of a direct transfer type image forming apparatus. In FIG. 10, elements having the same or corresponding functions and configurations as those of the image forming apparatus of FIG. An image forming apparatus 100 in FIG. 10 has a recording material carrying belt 107 constituted by an endless belt as a recording material carrying body, instead of the intermediate transfer belt 7 in the image forming apparatus 100 in FIG. In the image forming apparatus 100 of FIG. 10, the toner image formed on the photosensitive drum 1 in each image forming unit S is transferred to the recording material P carried and conveyed on the recording material carrying belt 107 in each transfer unit N. Is done. Also in such a direct transfer type image forming apparatus 100, when the belt unit 70 including the recording material carrying belt 107 is attached / detached particularly along the width direction of the recording material carrying belt 107, the above-described intermediate transfer type image forming apparatus 100 is used. Problems similar to those of the image forming apparatus 100 may occur. Therefore, the present invention can be applied to a direct transfer type image forming apparatus, and the same effects as those of the above-described embodiments can be obtained.

DESCRIPTION OF SYMBOLS 1 Photosensitive drum 5 Primary transfer roller 7 Intermediate transfer belt 20 Switching mechanism 21 Rotating shaft 22 Moving member 22a Guide part 23 Guide pin 24 Handle 70 Intermediate transfer unit (belt unit)
79 Handle part

Claims (14)

In a belt unit that can be attached to and detached from an apparatus main body of an image forming apparatus including a plurality of image carriers that carry toner images,
A plurality of tension rollers,
An endless belt that is stretched and conveyed by the plurality of stretching rollers, and a toner image is transferred from the plurality of image carriers or a toner image is transferred from the plurality of image carriers. An endless belt carrying a recording material;
A switching mechanism that switches between a first state in which at least one of the plurality of image carriers and the belt are in contact with each other and a second state in which all of the plurality of image carriers and the belt are separated from each other. A switching mechanism comprising a rotatable pivot shaft and a moving member that moves in synchronization with the pivot of the pivot shaft;
A handle for holding the belt unit when handling the belt unit;
Have
The grip unit is connected to the rotating shaft, and is a belt unit.   The grip portion is rotatable between a first position housed in the belt unit and a second position protruding outward from the belt unit with the rotation shaft as a rotation center. The belt unit according to claim 1, wherein the belt unit is provided.   3. The belt unit according to claim 1, wherein the belt unit is attached to and detached from the apparatus main body by being moved in a direction substantially perpendicular to a conveyance direction of the belt.   The belt unit according to any one of claims 1 to 3, wherein the rotation shaft extends in a direction substantially orthogonal to a conveyance direction of the belt.   The operation unit for rotating the rotation shaft is provided on a side portion of the belt unit on the upstream side in a direction in which the belt unit is attached to the apparatus main body. The belt unit according to one item.   2. The rotating shaft is provided on a downstream side or an upstream side of a center of gravity position of the belt unit in a moving direction of a surface of the belt facing the plurality of image carriers. The belt unit as described in any one of -5.   In order to hold the belt unit when handling the belt unit on the opposite side of the rotation shaft with respect to the center of gravity of the belt unit in the moving direction of the belt surface facing the plurality of image carriers. The belt unit according to claim 6, wherein a holding portion is provided.   The belt unit according to any one of claims 1 to 7, wherein the grip portion is provided at a position overlapping the belt in a direction substantially orthogonal to a conveyance direction of the belt.   9. The grip portion according to claim 8, wherein the grip portion is provided at a position shifted in a direction substantially perpendicular to a conveying direction of the belt to a side where a center of gravity of the belt unit is located with respect to a center of the belt. The belt unit described.   The belt unit is disposed above the plurality of image carriers when mounted on the apparatus main body, and the rotation shaft is disposed above the belt. The belt unit according to claim 9. The belt unit is
A plurality of transfer members provided on the inner peripheral surface side of the belt corresponding to each of the plurality of image carriers, and transferring a toner image from the corresponding image carrier to the belt or a recording material carried on the belt. When,
A first position where a transfer member corresponding to an image carrier other than the most downstream image carrier in the conveying direction of the belt among the plurality of image carriers is in contact with the corresponding image carrier via the belt; A separation mechanism for separating the belt from a corresponding image carrier and moving the belt between a second position farther from the corresponding image carrier than the first position;
Have
The switching mechanism includes a third position where the transfer member corresponding to the most downstream image carrier is brought into contact with the most downstream image carrier via the belt, and the belt from the most downstream image carrier. Is switched between the first state and the second state by moving between the fourth position and the fourth position farther from the most downstream image carrier than the third position,
The rotation shaft is disposed closest to a transfer member corresponding to the most downstream image carrier among the plurality of transfer members in a moving direction of a surface of the belt facing the plurality of image carriers. The belt unit according to any one of claims 1 to 10, wherein:   The belt unit according to claim 1, wherein the moving member rotates in synchronization with the rotation shaft. In the belt unit that can be attached to and detached from the main body of the image forming apparatus,
An endless belt,
A plurality of stretching rollers that stretch the endless belt;
A switching mechanism that changes the posture of the belt when viewed in the width direction of the belt, the switching mechanism having a rotatable rotation shaft and a moving member that moves in synchronization with the rotation shaft. When,
A handle for holding the belt unit when handling the belt unit;
Have
The grip unit is connected to the rotating shaft, and is a belt unit.   An image forming apparatus comprising: an image carrier that carries a toner image; and the belt unit according to claim 1.

Images