Image forming apparatus

Abstract

To provide an image forming apparatus that, with a simple configuration, can stably release the engagement between an apparatus body and an intermediate transfer unit.SOLUTION: An image forming apparatus comprises: an apparatus body; an intermediate transfer unit that is mounted removably in a first direction in the apparatus body; and a body-side coupling that transmits power to the intermediate transfer unit. The intermediate transfer unit includes: a unit-side coupling that engages with the body-side coupling in a second direction perpendicular to the first direction, and when moving in one direction of the second direction, releases the engagement; and a release lever having an operating part that is provided at one end and can be operated in a third direction perpendicular to the first direction and the second direction, and a pushing part that is provided at the other end, and when the operating part is operated in one direction of the third direction, pushes the unit-side coupling in one direction of the second direction.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to an image forming apparatus.

Background Art

[0002] Generally, in an electrophotographic image forming apparatus, after charging the surface of a drum-shaped or belt-shaped photoreceptor, an electrostatic latent image based on an image signal is written on the surface of the photoreceptor, and the electrostatic latent image is developed with toner. Then, the toner image on the surface of the photoreceptor is first transferred to an intermediate transfer member, and then secondarily transferred to a transfer material such as paper. As the intermediate transfer member, an intermediate transfer belt formed of an endless belt is often used.

[0003] The intermediate transfer belt generally needs to be replaced regularly in order to avoid troubles due to deterioration. In order to facilitate the replacement of the intermediate transfer belt, the intermediate transfer belt, a driving roller for rotationally driving the intermediate transfer belt, etc. are integrally unitized into an intermediate transfer unit, and the intermediate transfer unit is detachable from the apparatus main body of the image forming apparatus.

[0004] Normally, a power source for rotationally driving a driving roller etc. of the intermediate transfer unit is provided in the apparatus main body. Therefore, in a state where the intermediate transfer unit is attached to the apparatus main body, a configuration such as a coupling that engages with each other in a direction along the rotation axis of the power source and the rotation axis of the driving roller is required so that the driving force is transmitted from the power source of the apparatus main body to the intermediate transfer unit. Further, for example, when the attaching / detaching direction of the intermediate transfer unit with respect to the apparatus main body is orthogonal to the direction along the rotation axis of the power source and the rotation axis of the driving roller, a configuration for releasing the engagement of the coupling is also required when removing the intermediate transfer unit from the apparatus main body.

[0005] For example, Patent Document 1 discloses a configuration for releasing the engagement between the main body side coupling of the apparatus main body and the unit side coupling of the intermediate transfer belt unit, in which a release member provided on the gripping portion of the intermediate transfer belt unit is disclosed. The release member is held in a position where it is biased by a gripping spring and does not contact the main body side coupling and the unit side coupling in a state where the intermediate transfer unit is attached to the apparatus main body. Further, when removing the intermediate transfer belt unit from the apparatus main body, the release member is slid in a direction to remove the intermediate transfer belt unit from the apparatus main body, and the main body side coupling is pushed and moved by the release member to release the engagement with the unit side coupling, so that the intermediate transfer belt unit can be removed from the apparatus main body.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, the release member of Patent Document 1 has a complicated structure including a gripping spring as the above-described biasing member, a hole for passing the main body side coupling, etc., which leads to an increase in cost. Further, the direction in which the release member pushes the main body side coupling is orthogonal to the moving direction of the main body side coupling, and since the release member pushes so as to rub the circumferential surface of the coupling, the operation of releasing the engagement of the coupling may become unstable.

[0008] An object of the present disclosure is to provide an image forming apparatus capable of stably releasing the engagement between the apparatus main body and the intermediate transfer unit with a simple structure in a configuration in which the attachment and detachment of the intermediate transfer unit to and from the apparatus main body is performed in a direction orthogonal to the engagement direction of the coupling.

Means for Solving the Problems

[0009] An image forming apparatus according to an aspect of the present disclosure includes an apparatus main body, an intermediate transfer unit detachably attached to the apparatus main body in a first direction, and a main body side coupling that transmits power to the intermediate transfer unit. The intermediate transfer unit includes a unit side coupling that engages with the main body side coupling in a second direction perpendicular to the first direction and is disengaged when moved in one direction of the second direction, an operation unit provided at one end and operable in a third direction perpendicular to the first and second directions, and a pushing unit provided at the other end that pushes and moves the unit side coupling in one direction of the second direction when the operation unit is operated in one direction of the third direction. The intermediate transfer unit further includes a release lever having the pushing unit.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

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Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Mode for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Regarding the drawings, the same or equivalent elements are denoted by the same reference numerals, and duplicate explanations are omitted. In addition, the embodiments described below do not unduly limit the content of the present disclosure described in the claims, and not all of the configurations described in the embodiments are essential as the solution means of the present disclosure.

[0012] <Image forming apparatus> FIG. 1 is a schematic sectional view showing the internal structure of an image forming apparatus 100 according to the present disclosure. In the following description, the left-right direction in FIG. 1 is defined as the first direction, and the up-down direction is defined as the third direction. The image forming apparatus 100 is, for example, a multifunction machine having functions such as a copying function, a printer function, a scanner function, and a facsimile function, and forms a multi-color or single-color image on printing paper by an electrophotographic method. Note that the image forming apparatus 100 of the present disclosure is not limited to a multifunction machine, and may be, for example, a printer having only a printer function.

[0013]

[0014] ​The apparatus main body 101 includes a control device 103, a photoreceptor 104, an exposure device 105, a developing device 106, an intermediate transfer unit 200, a secondary transfer roller 107, a fixing unit 108, an automatic paper feed tray 109, a manual paper feed tray 110, a paper discharge tray 111, etc.

[0015] The control device 103 is a device that controls the image forming apparatus 100. The control device 103 is composed of a microcontroller and peripheral circuits. The microcontroller includes a processor and a memory. The processor executes a control program stored in the memory to operate the microcontroller and peripheral circuits as the control device 103. All or part of the processing performed by the microcontroller may be performed by a dedicated electronic circuit. The control device 103 includes a communication unit that receives external data, signals, etc. The control device 103 transmits various data such as image data and control signals to each device included in the image forming apparatus 100 in response to an input operation by the user, reception of external data, etc., and causes the image forming apparatus 100 to execute various operations.

[0016] The photoreceptor 104 includes a cylindrical substrate having conductivity and a photosensitive layer provided on the outside of the substrate. The photosensitive layer exhibits insulating properties when not irradiated with light, and exhibits conductive properties in the irradiated region. The circumferential surface of the photosensitive layer is charged to a predetermined potential. The photoreceptor 104 has a rotation axis (not shown) along the axis and rotates about the rotation axis by a motor (not shown).

[0017] The exposure device 105 irradiates light for exposing the circumferential surface of the photosensitive layer of the photoreceptor 104. The exposure device 105 irradiates the circumferential surface of the photosensitive layer of the photoreceptor 104 with light for forming an image based on the image data transmitted from the control device 103. The circumferential surface of the photoreceptor 104 charged by the light irradiated by the exposure device 105 is exposed, and an electrostatic latent image corresponding to the image data is formed on the circumferential surface of the photosensitive layer of the photoreceptor 104.

[0018] The developing device 106 supplies toner onto the circumferential surface of the photosensitive layer of the photosensitive member 104, develops the electrostatic latent image on the circumferential surface of the photosensitive member 104, and forms a toner image. The present disclosure exemplifies an image forming apparatus 100 capable of printing a full-color image, and realizes full-color image printing by superimposing monochromatic images corresponding to each of the four colors of cyan, magenta, yellow, and black. Therefore, the image forming apparatus 100 includes four photosensitive members 104, four exposure devices 105, and four developing devices 106 corresponding to each of the above four colors. For example, each of the four photosensitive members 104 and the four developing devices 106 has the same structure, and only the color of the toner supplied by the developing device 106 to the photosensitive member 104 is different. Although not shown in the present disclosure, an image forming apparatus capable of printing a monochrome image is composed of only a photosensitive member, an exposure device, and a developing device corresponding to black, unlike a full-color one.

[0019] The intermediate transfer unit 200 is disposed above the four photosensitive members 104. The intermediate transfer unit 200 is an integrated unit including four intermediate transfer rollers 201 corresponding to the four photosensitive members 104, an intermediate transfer belt 202 onto which the toner image of the photosensitive member 104 is transferred by the intermediate transfer roller, a driving roller 203 that stretches and rotationally drives the intermediate transfer belt 202, a tension roller 204, and the like. The intermediate transfer rollers 201 are pivotally supported by the intermediate transfer unit 200 so that the intermediate transfer belt 202 rotates therewith. Although details will be described later, power for rotating the driving roller 203 is transmitted from an electric motor, which is a driving source provided in the apparatus main body 101, to the driving roller 203 by a coupling structure, and the intermediate transfer belt 202 rotates when the driving roller 203 rotates.

[0020] The intermediate transfer unit 200 is detachably fixed to the apparatus main body 101 in a first direction. The first direction is the left-right direction in FIG. 1, and the intermediate transfer unit 200 can be removed from the apparatus main body 101 in the direction of the dotted line in FIG. 1. As can be seen from FIG. 1, the detachment direction of the intermediate transfer unit 200 with respect to the apparatus main body 101 is orthogonal to the direction along the rotation axis of the driving roller 203.

[0021] When current is supplied from a power source (not shown) to the intermediate transfer roller 201, a transfer electric field is formed between the photoreceptor 104 and the intermediate transfer belt 202 at the position of the intermediate transfer roller 201. Due to the action of the transfer electric field, the toner image developed on the circumferential surface of the photoreceptor 104 is transferred onto the intermediate transfer belt 202. By each of the four intermediate transfer rollers 201, toner images corresponding to each of the four colors of cyan, magenta, yellow, and black are sequentially transferred and superimposed onto the intermediate transfer belt 202, and a full-color toner image is formed on the intermediate transfer belt 202.

[0022] The secondary transfer roller 107 is a member that transfers the toner image onto the printing paper. For example, it is arranged to contact the intermediate transfer belt 202 on the driving roller 203. The printing paper supplied from the automatic paper feed tray 109 or the manual paper feed tray 110 is conveyed by a plurality of conveying rollers 112 and passes between the secondary transfer roller 107 and the intermediate transfer belt 202. When the printing paper passes between the secondary transfer roller 107 and the intermediate transfer belt 202, the toner image formed on the intermediate transfer belt 202 is transferred onto the printing paper. The toner image transferred onto the printing paper is heated and pressure-bonded by a fixing unit 108 including a heating roller, a pressure roller, etc., and is fixed to the printing paper. As described above, the image forming apparatus 100 completes the printing of the image onto the printing paper based on the received image data. The printed paper after printing is discharged to the paper discharge tray 111.

[0023] <Intermediate Transfer Unit> Figure 2 is a perspective view showing the intermediate transfer unit 200 according to the present disclosure. As shown in Figure 2, the front-rear direction of the intermediate transfer unit 200 is defined as the first direction, the left-right direction is defined as the second direction, and the up-down direction is defined as the third direction. When the intermediate transfer unit 200 is mounted on the apparatus main body 101, the front side of the intermediate transfer unit 200 in Figure 2 is the right side of the intermediate transfer unit 200 in Figure 1, and the rear side of the intermediate transfer unit 200 in Figure 2 is the left side of the intermediate transfer unit 200 in Figure 1. Therefore, when replacing the intermediate transfer unit 200, the operator holds the intermediate transfer unit 200 from the front side and performs the attachment / detachment operation between the apparatus main body 101 and the intermediate transfer unit 200. Thus, the first direction in which the intermediate transfer unit 200 is attached / detached to / from the apparatus main body 101 is the front-rear direction in Figure 2.

[0024] The intermediate transfer unit 200 includes an intermediate transfer belt 202, a drive roller 203 that rotates the intermediate transfer belt 202, a unit-side coupling 400 for transmitting the power of the electric motor of the apparatus main body 101 to the drive roller 203, and a frame 300 that fixes them as an integral unit. Although details will be described later, the unit-side coupling 400 can engage with a main body-side coupling 150 driven by the power of the electric motor of the apparatus main body 101. Also, although details will be described later, the frame 300 includes a release lever 500 that can release the engagement between the main body-side coupling 150 and the unit-side coupling 400.

[0025] <State before operation of the release lever> Figure 3 is an enlarged perspective view of the periphery of the release lever 500 and the unit-side coupling 400 in Figure 2, showing the state before operating the release lever 500 of the present disclosure. Therefore, Figures 2 and 3 show the intermediate transfer unit 200 in a state attached to an apparatus main body 101 not shown. Although details will be described later, the unit-side coupling 400 is engaged with a main body-side coupling 150 not shown.

[0026] <Engagement between the unit-side coupling and the main body-side coupling> FIG. 4 is a schematic diagram showing components related to the unit-side coupling 400 of the present disclosure, and is a perspective view of the intermediate transfer unit in FIG. 3 from above. More specifically, FIG. 4 is a schematic diagram showing a state in which the unit-side coupling 400 and the main body-side coupling 150 are engaged. In FIG. 4, the configurations of the intermediate transfer unit 200 and the apparatus main body 101 are appropriately omitted so that the structures of the respective components are easily understandable. The vertical direction in FIG. 4 is defined as the first direction, and the horizontal direction is defined as the second direction. Therefore, the first direction in which the intermediate transfer unit 200 is attached to and detached from the apparatus main body 101 is the vertical direction in FIG. 4.

[0027] As can be seen from FIGS. 3 and 4, in the intermediate transfer unit 200 attached to the apparatus main body 101, before the release lever 500 is operated, the unit-side coupling 400 and the main body-side coupling 150 are engaged in the second direction perpendicular to the first direction. In FIG. 4, since the first direction is the vertical direction, the second direction is the horizontal direction.

[0028] The unit-side coupling 400 is fixed to one end of a unit-side rotation drive shaft 401 having a rotation axis in the second direction so as to be slidable along the second direction as indicated by the dotted arrow in FIG. 4. The unit-side coupling 400 and the unit-side rotation drive shaft 401 are integrated so as to be rotatable around the rotation axis in the second direction and are fixed to the frame 300. As shown in FIG. 4, the biasing spring 420 applies an elastic force to the unit-side coupling 400 in a direction protruding from the frame 300 along the second direction. The unit-side coupling 400 protruding due to the elastic force of the biasing spring 420 is engaged with the main body-side coupling 150.

[0029] The main body side coupling 150 is fixed to the apparatus main body 101 so as to be rotationally driven around the rotation axis in the second direction by the power of an electric motor (not shown). As shown in FIG. 4, in a state where the main body side coupling 150 and the unit side coupling 400 are engaged, the power of the electric motor is transmitted to the unit side coupling 400 via the main body side coupling 150, and the drive roller 203 is rotationally driven via the unit side rotation drive shaft 401 that rotates integrally with the unit side coupling 400.

[0030] FIG. 5 is a block diagram showing a part of the image forming apparatus 100 according to the present disclosure. The apparatus main body 101 includes a control device 103, an electric motor 140, and a main body side coupling 150, and the intermediate transfer unit 200 includes a unit side coupling 400. The control device 103 controls the rotation of the electric motor 140, and the power of the electric motor 140 is transmitted and the main body side coupling 150 rotates. In a state where the intermediate transfer unit 200 is attached to the apparatus main body 101, since the main body side coupling 150 and the unit side coupling 400 are engaged as described above, the power of the electric motor 140 is transmitted to the unit side coupling 400 via the main body side coupling 150. In this way, the power of the electric motor 140 of the apparatus main body 101 is transmitted to the intermediate transfer unit 200.

[0031] FIGS. 6 and 7 are exploded views of the intermediate transfer unit 200 of the present disclosure shown in FIG. 3 with the release lever 500 removed from the frame 300. FIG. 6 is an exploded perspective view seen from the front side in the first direction of the intermediate transfer unit 200 in FIG. 3, and FIG. 7 is an exploded perspective view seen from the rear side in the first direction of the intermediate transfer unit 200 in FIG. 3.

[0032] The release lever 500 includes an operation part 510 provided at one end and a pushing part 520 provided at the other end. Although details will be described later, the operation part 510 can be operated in a third direction perpendicular to the first direction and the second direction, and the pushing part 520 can push and move the unit side coupling 400 in one direction in the second direction. In FIGS. 3, 6, and 7, the third direction is the vertical direction of the intermediate transfer unit 200.

[0033] <Support part> The release lever 500 includes a support part 540 provided between the operation part 510 and the pressing part 520. As can be seen from FIGS. 6 and 7, the support part 540 is rotatable in the second direction and rotatable in the third direction and is attached to the frame 300. In the present disclosure, the support part 540 has a cylindrical structure with its circumferential surface facing up, down, front, and back, and an example of a structure in which a cylinder is attached to the frame 300 through a long hole is illustrated.

[0034] <Structure of the support part and the frame> The frame 300 has a first wall part 310 and a second wall part 320 that sandwich the support part 540 in the third direction. The support part 540 has a first curved surface 541 convex toward the first wall part 310 and a second curved surface 542 convex toward the second wall part 320. One of the first curved surface 541 and the first wall part 310 has a first long hole 610 extending in the first direction, and the other has a first cylindrical part 611 passing through the first long hole 610. Also, one of the second curved surface 542 and the second wall part 320 has a second long hole 620 extending in the first direction, and the other has a second cylindrical part 621 passing through the second long hole 620. Thereby, with respect to the frame 300, the support part 540 can rotate around the rotation axis in the third direction, and the first cylindrical part 611 and the second cylindrical part 621 can move along the first curved surface 541 and the second curved surface 542 while sliding inside the first long hole 610 and the second long hole 620, so that it can also rotate around the rotation axis in the second direction. That is, the support part 540 can rotate around two rotation axes, namely, the rotation axis in the third direction and the rotation axis in the second direction. Note that slits may be provided in the vicinity of the roots of the first cylindrical part 611 and the second cylindrical part 621 to make elastic deformation easier and make it easier to attach the support part 540 to the frame 300.

[0035] In the structures shown in FIGS. 6 and 7, an example is illustrated in which the first wall portion 310 has the first long hole 610, the first curved surface 541 has the first cylindrical portion 611, the second curved surface 542 has the second long hole 620, and the second wall portion 320 has the second cylindrical portion 621. This configuration is preferable in that the first long hole 610 and the first cylindrical portion 611 can be fitted together with the second curved surface 542, which is the lower surface of the support portion 540, being stabilized on the second wall portion 320, and the support portion 540 can be easily attached by the frame 300.

[0036] FIG. 8 is a side view of the intermediate transfer unit 200 of FIG. 3. FIG. 9 is a cross-sectional view taken along line IX-IX of FIG. 8. FIG. 10 is a cross-sectional view taken along line X-X of FIG. 8. FIG. 11 is a cross-sectional view taken along line XI-XI of FIG. 8. The vertical direction in FIG. 8 is defined as the third direction, and the horizontal direction is defined as the first direction. The vertical direction in FIGS. 9 and 11 is defined as the third direction, and the horizontal direction is defined as the second direction. The vertical direction in FIG. 10 is defined as the first direction, and the horizontal direction is defined as the second direction. Note that in FIGS. 8, 9, and 11, the illustration of the main body side coupling 150 is omitted.

[0037] As can be seen from FIGS. 8 and 10, in the state before the operation portion 510 is operated, the pushing portion 520 is separated from the unit side coupling 400 and retracted downward so as not to interfere with the rotational drive of the unit side coupling 400.

[0038] <Locking portion> In the present disclosure, the frame 300 has a locking portion 350 on the lower side, which is one direction of the third direction, with respect to the pushing portion 520. When the operation portion 510 is not being operated, the pushing portion 520 is placed on the upper surface of the locking portion 350 and is locked by the weight of the pushing portion 520 and the frictional force between the pushing portion 520 and the locking portion 350. Thereby, it is possible to suppress the pushing portion 520 from moving and shifting in position due to the vibration generated by the rotational drive of the unit side coupling 400.

[0039] In the present disclosure, although a case where one direction of the third direction is downward is exemplified, one direction of the third direction may be upward. In that case, an urging member such as a spring may be provided between the release lever 500 and the frame 300 so as to retract the pushing portion 520 upward with respect to the unit-side coupling 400. For example, a spring that pulls up the pushing portion 520 may be provided between the frame 300 and the pushing portion 520.

[0040] <Explanation of the movement when operating the release lever> When removing the intermediate transfer unit 200 from the apparatus main body 101, it is necessary to move the unit-side coupling 400 in one direction of the second direction to release the engagement between the main body-side coupling 150 and the unit-side coupling 400. One direction of the second direction is the direction in which the unit-side coupling 400 moves away from the main body-side coupling 150, which is the left direction in FIGS. 9 and 10 and the right direction in FIG. 11.

[0041] In the present disclosure, when releasing the engagement between the main body-side coupling 150 and the unit-side coupling 400, the operation portion 510 is operated to move in one direction of the third direction. In the present disclosure, a case where one direction of the third direction is downward with respect to the intermediate transfer unit 200 is exemplified. FIGS. 8, 9, 10, and 11 show, by dotted arrows, how the support portion 540 and the pushing portion 520 move when the operation portion 510 is moved downward.

[0042] As shown in FIG. 8, when the operation portion 510 is moved downward, the support portion 540 rotates clockwise around the rotation axis in the second direction in FIG. 8. Thereby, the pushing portion 520 moves upward in the direction opposite to the movement of the operation portion 510 with the support portion 540 as a fulcrum.

[0043] <Inclined portion> The frame 300 is provided on one side in one direction of the third direction with respect to the operation unit 510, and has an inclined portion 330 that inclines in one direction of the third direction as it goes in the direction opposite to one direction of the second direction. As shown in FIG. 9, in the present disclosure, one side in one direction of the third direction is the lower side, and the direction opposite to one direction of the second direction is the right direction in which the unit-side coupling 400 approaches the body-side coupling 150. Therefore, the inclined portion 330 in FIG. 9 is provided below the operation unit 510 and inclines downward as it goes to the right. As shown by the dotted arrow in FIG. 9, when the operation unit 510 is moved downward, the lower surface, which is the surface on one side in one direction of the third direction of the operation unit 510, abuts against the inclined portion 330 and is guided to move obliquely downward along the inclination of the inclined portion 330. Therefore, the movement of the operation unit 510 is changed by the inclined portion 330 into a movement including a component in the second direction in addition to the third direction.

[0044] As shown in FIG. 10, when the operation unit 510 moves in the right direction, which is the direction opposite to one direction of the second direction, the support unit 540 rotates clockwise around the rotation axis in the third direction. Thereby, the pushing unit 520 moves leftward, contrary to the movement of the operation unit 510, with the support unit 540 as a fulcrum.

[0045] When the movements in FIGS. 8, 9, and 10 are combined, as shown in FIG. 11, the pushing unit 520 moves in the direction opposite to the diagonal direction of the operation unit 510 shown in FIG. 9. By this movement, the pushing unit 520 that has been retracted downward moves upward and abuts against the unit-side coupling 400, and can further push and move the unit-side coupling 400 in the direction away from the body-side coupling 150. Thus, in the present disclosure, since the movement of the pushing unit 520 includes a component in the same direction as the direction in which the unit-side coupling 400 moves away from the body-side coupling 150, the unit-side coupling 400 can be stably pushed and moved.

[0046] <Inclined surface of the operation unit> Note that the surface 511 on one side in the third direction of the operation unit 510 may be inclined parallel to the inclined portion 330. For example, in FIG. 9, the lower surface 511, which is the surface 511 on one side in the third direction of the operation unit 510, is inclined parallel to the opposing inclined portion 330. Thereby, since the surface 511 on one side in the third direction of the operation unit 510 and the inclined portion 330 can slide while being in surface contact with each other, the movement of the operation unit 510 can be stably guided.

[0047] <State after operating the release lever> FIG. 12 is a perspective view showing the state after operating the release lever 500 of the present disclosure. FIG. 13 is a side view of the intermediate transfer unit 200 in FIG. 12. FIG. 14 is a cross-sectional view taken along the line XIV-XIV in FIG. 13. FIG. 15 is a cross-sectional view taken along the line XV-XV in FIG. 13. As shown in FIG. 12, the front-rear direction of the intermediate transfer unit 200 is defined as the first direction, the left-right direction is defined as the second direction, and the up-down direction is defined as the third direction. The up-down direction in FIG. 13 is defined as the third direction, and the left-right direction is defined as the first direction. The up-down direction in FIG. 14 is defined as the third direction, and the left-right direction is defined as the second direction. The up-down direction in FIG. 15 is defined as the first direction, and the left-right direction is defined as the second direction. Note that in FIGS. 12, 13, and 14, the main body side coupling 150 is omitted.

[0048] As shown in FIGS. 12 and 13, after moving the operation unit 510 downward, with the support portion 540 as a fulcrum, the pushing portion 520 moves upward, and its tip contacts the unit side coupling 400.

[0049] As shown in FIG. 14, the operation unit 510 is guided by the inclined portion 330 and moves diagonally downward to the right. As a result, as described above, the pushing unit 520 moves diagonally upward to the left in the direction opposite to the operation unit 510. Due to this movement, as shown in FIG. 15, the pushing unit 520 that is in contact with the unit-side coupling 400 pushes the unit-side coupling 400 in a direction away from the main body-side coupling 150, and the engagement of the unit-side coupling 400 with the main body-side coupling 150 is released. More specifically, before operating the operation unit 510, as shown in FIG. 10, the unit-side coupling 400 protrudes outside the frame 300, and after operating the operation unit 510, as shown in FIG. 15, the unit-side coupling 400 moves to a position where it is pushed inside the frame 300. In this state, the unit-side coupling 400 does not hit the apparatus main body 101, and the intermediate transfer unit 200 can be attached to and detached from the apparatus main body 101 in the first direction.

[0050] <Grip portion> The frame 300 may have a grip portion 340 provided on one side in the third direction with respect to the inclined portion 330. In the present disclosure, as shown in FIGS. 13 and 14, the frame 300 has a lower surface as the grip portion 340 on the lower side, which is one side in the third direction with respect to the inclined portion 330. A user who attaches and detaches the intermediate transfer unit 200 can attach and detach the intermediate transfer unit 200 by gripping the operation unit 510 and the grip portion 340 while operating the operation unit 510 in one direction in the third direction. In other words, the user can surely move the intermediate transfer unit 200 along the first direction while gripping the upper surface of the operation unit 510 and the grip portion 340 with the hand.

[0051] <Detailed description of the release lever and the unit-side coupling> FIG. 16 is a schematic view showing the unit-side coupling 400 after operating the release lever 500. FIG. 17 is a plan view of FIG. 16 seen from above. In FIG. 16, the front-rear direction of the release lever 500 is defined as the first direction, the left-right direction is defined as the second direction, and the up-down direction is defined as the third direction. In FIG. 17, the up-down direction is defined as the first direction, and the left-right direction is defined as the second direction. In FIGS. 16 and 17, only the release lever 500 and the unit-side coupling 400 are illustrated for easy understanding of the description.

[0052] In the present disclosure, the unit-side coupling 400 is a cylinder having a groove portion 410 that extends around the outer peripheral surface. As shown in FIG. 16, when the operation portion 510 is operated downward, which is one direction in the third direction, the tip of the pushing portion 520 that has moved upward enters into the groove portion 410.

[0053] As shown in FIG. 17, the left side surface of the tip of the pushing portion 520 abuts against the side surface 411 of the groove. Further, when the operation portion 510 is operated downward, the pushing portion 520 pushes the side surface 411 of the groove in the left direction, which is one direction in the second direction, to move the unit-side coupling 400 to the left. Therefore, the movement of the pushing portion 520 includes a component in the same direction as the direction in which the unit-side coupling 400 moves away from the main body-side coupling 150, and since the pushing portion 520 and the side surface 411 of the groove are in surface contact with each other, the unit-side coupling 400 can be pushed and moved more stably.

[0054] Note that in the present disclosure, an example is illustrated in which the unit-side coupling 400 has the groove portion 410 and the pushing portion 520 pushes the side surface 411 of the groove, but the present disclosure is not limited to this configuration. For example, the unit-side coupling 400 may have a flange provided along the circumferential surface of the cylinder instead of the groove portion 410, and the pushing portion 520 may move the unit-side coupling 400 by pushing the flange.

[0055] <Shape of the tip of the pushing portion> Note that the pushing portion 520 may be reduced in width in the second direction as it extends toward the tip of the pushing portion 520. For example, in the present disclosure, as shown in FIGS. 10 and 15, the pushing portion 520 has a tapered shape in which the width in the left-right direction, which is the second direction, decreases from the base on the support portion 540 side toward the tip on the opposite side. As a result, as shown in FIG. 10, the pushing portion 520 can be made less likely to protrude outside the frame 300 when the release lever 500 is not being operated, and as shown in FIG. 15, it is possible to prevent the pushing portion 520 from interfering with the internal structure of the frame 300 when the unit-side coupling 400 is moved.

[0056] <Bending portion> Further, the pushing portion 520 may have a bending portion 530 that bends in one direction in the third direction. For example, in the present disclosure, as shown in FIG. 8 and the like, an example is illustrated in which the pushing portion 520 has a bending portion 530 that bends downward, which is one direction in the third direction. The greater the length from the tip of the operating portion 510 to the support portion 540 compared to the length from the support portion 540 to the tip of the pushing portion 520, the greater the unit-side coupling 400 can be moved with a smaller operating amount. However, when the release lever 500 is a straight bar-shaped member, as the release lever 500 becomes longer, in order to retract the pushing portion 520 from the unit-side coupling 400, the distance between the unit-side coupling 400 and the support portion 540 may need to be made longer, or the operating amount may increase due to an increase in the space required for retraction. By having the bending portion 530 on the pushing portion 520, it becomes easier to retract the pushing portion 520 from the unit-side coupling 400, and an increase in the operating amount can be suppressed.

[0057] Note that the present disclosure is not limited to the configurations of the above-described embodiments and modifications, and may be replaced with a configuration that is substantially the same as the configurations shown in the above-described embodiments and modifications, a configuration that exhibits the same operational effects, or a configuration that can achieve the same purpose.

Description of Reference Numerals

[0058] 100: Image forming apparatus 101: Apparatus main body 102: Image reading device 103: Control device 104: Photoconductor 105: Exposure device 106: Developing device 107: Secondary transfer roller 108: Fixing unit 109: Automatic paper feed tray 110: Manual paper feed tray 111: Paper discharge tray 112: Conveyor roller 140: Electric motor 150: Main body side coupling 151: Main body side rotation drive shaft 200: Intermediate transfer unit 201: Intermediate transfer roller 202: Intermediate transfer belt 203: Driving roller 204: Tension roller 300: Frame 310: First wall portion 320: Second wall portion 330: Inclined portion 340: Gripping portion 350: Locking portion 400: Unit side coupling 401: Unit side rotation drive shaft 410: Groove portion 411: Side surface of the groove portion 420: Biasing spring 500: Release lever 510: Operation portion 511: Surface on one side in the third direction 520: Pushing portion 530: Bent portion 540: Support portion 541: First curved surface 542: Second curved surface 610: First long hole 611: First cylindrical portion 620: Second long hole 621: Second cylindrical portion

Claims

1. An apparatus main body, an intermediate transfer unit detachably attached to the apparatus main body in a first direction, and a main body side coupling for transmitting power to the intermediate transfer unit, wherein the intermediate transfer unit includes a unit side coupling that engages with the main body side coupling in a second direction perpendicular to the first direction and is disengaged when moved in one direction of the second direction, and a release lever having an operation portion provided at one end and operable in a third direction perpendicular to the first direction and the second direction, and a pushing portion provided at the other end that pushes and moves the unit side coupling in one direction of the second direction when the operation portion is operated in one direction of the third direction. The image forming apparatus is provided.

2. The intermediate transfer unit further has a frame, wherein the release lever is provided between the operation portion and the pushing portion, and has a support portion that is rotatable around a rotation axis in the third direction and rotatable around a rotation axis in the second direction and is attached to the frame. The image forming apparatus according to claim 1.

3. The frame has a first wall portion and a second wall portion that sandwich the support portion in the third direction, the support portion has a first curved surface convex toward the first wall portion and a second curved surface convex toward the second wall portion, one of the first curved surface and the first wall portion has a first long hole extending in the first direction, and the other has a first cylindrical portion passing through the first long hole, one of the second curved surface and the second wall portion has a second long hole extending in the first direction, and the other has a second cylindrical portion passing through the second long hole. The image forming apparatus according to claim 2.

4. The frame is provided on one side in the third direction with respect to the operation portion, and has an inclined portion that inclines in one direction of the third direction as going in a direction opposite to one direction of the second direction, when the operation portion is operated in one direction of the third direction, the operation portion moves in an oblique direction along the inclined portion, and the pushing portion moves in a direction opposite to the oblique direction. The image forming apparatus according to claim 2.

5. A surface on one side in the third direction of the operation portion is inclined parallel to the inclined portion. The image forming apparatus according to claim 4.

6. The frame has a gripping portion provided on one side in the third direction with respect to the inclined portion, The image forming apparatus according to claim 4, wherein the intermediate transfer unit can be attached and detached by a user gripping the operation unit and the gripping unit in a state where the operation unit is operated in one direction of the third direction.

7. The image forming apparatus according to claim 2, wherein the frame is provided on one side in one direction of the third direction with respect to the pushing portion, and has a locking portion for locking the pushing portion when the operation unit is not being operated.

8. The image forming apparatus according to claim 2, wherein the width of the pushing portion in the second direction decreases as it goes toward the tip of the pushing portion.

9. The image forming apparatus according to claim 2, wherein the pushing portion has a bent portion that bends in one direction of the third direction.

10. The unit-side coupling is a cylinder having a groove portion that extends around the outer peripheral surface, The image forming apparatus according to claim 2, wherein when the operation unit is operated in one direction of the third direction, the pushing portion pushes the side surface of the groove portion in one direction of the second direction.

Images