JP2017223803A - Process cartridge and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus having a configuration that can suppress fall of a process cartridge attached to an apparatus body without preventing a reduction in weight of the apparatus.SOLUTION: An image forming apparatus forms an image on a recording material, and comprises: an apparatus body that includes a pair of lateral plate parts facing each other; and a process cartridge that is removably attached to the apparatus body and that has both end parts engaged with support parts provided respectively in the pair of lateral plate parts, and is thereby supported by the pair of lateral plate parts. One lateral plate part of the pair of lateral plate parts includes a fall prevention part that can support an end part coming off from the support part in one of the lateral plate parts due to a change in relative position in an opposite direction between the pair of lateral plate parts and process cartridge.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an image forming apparatus using an electrophotographic system.

  2. Description of the Related Art An electrophotographic image forming apparatus (hereinafter referred to as an image forming apparatus) such as a copying machine or a printer has a so-called process cartridge system. That is, in the apparatus configuration of the image forming apparatus, the members related to the image forming process are integrated as a process cartridge and configured to be detachable from the apparatus main body, thereby improving the maintainability. In such an image forming apparatus, when packing and shipping as a product, the image forming apparatus may be packed with a process cartridge mounted in the apparatus main body in order to reduce the packing form. Further, in order to reduce the weight of the apparatus main body and reduce the cost, constituent parts of the apparatus main body are made of a plastic material, or the parts are thinned.

JP, 2015-14632, A

  However, when the apparatus main body is made plastic and thin, the rigidity of the apparatus main body may be lowered. In this case, if the product is packaged and shipped with the process cartridge mounted in the apparatus main body, the apparatus main body may be deformed due to vibration, impact, or the like when the product is transported, and the process cartridge may drop from a predetermined position.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus having a configuration capable of suppressing a process cartridge attached to an apparatus main body from dropping without impeding weight reduction of the apparatus.

In order to achieve the above object, an image forming apparatus of the present invention includes:
An image forming apparatus for forming an image on a recording material,
An apparatus main body having a pair of side plate portions facing each other;
A process cartridge that is attachable to and detachable from the apparatus main body, and is supported by the pair of side plate portions by engaging both ends with support portions respectively provided on the pair of side plate portions;
In an image forming apparatus comprising:
One side plate portion of the pair of side plate portions is disengaged from the support portion of the one side plate portion due to a change in relative position in the facing direction between the pair of side plate portions and the process cartridge. It is characterized by comprising a drop-off prevention part capable of supporting the end part.
In order to achieve the above object, the process cartridge of the present invention comprises:
A process cartridge that is detachable from an apparatus main body of an image forming apparatus that forms an image on a recording material,
In the process cartridge supported by the pair of side plates by engaging both ends with support portions respectively provided on a pair of side plates facing each other in the apparatus main body,
Due to a change in the relative position in the facing direction between the pair of side plate portions and the process cartridge, the end portion that is detached from the support portion of the one side plate portion becomes the support portion in the one side plate portion. It is configured to be supported by a protrusion protruding in the opposing direction provided,
In order to restrict relative movement between the protrusion and the protrusion in a direction orthogonal to the facing direction, the protrusion has a concave portion corresponding to the shape of the protrusion.

  According to the present invention, it is possible to prevent the process cartridge attached to the apparatus main body from dropping without impeding weight reduction of the apparatus.

1 is a schematic cross-sectional view of an image forming apparatus according to an embodiment of the present invention. Typical sectional drawing of the process cartridge of Example 1 The perspective view of the process cartridge of Example 1 The perspective view of the process cartridge of Example 1 The perspective view explaining the recessed part of the process cartridge of Example 1. FIG. Explanatory drawing of mounting the process cartridge of Example 1 on the apparatus main body Explanatory drawing of mounting the process cartridge of Example 1 on the apparatus main body Explanatory drawing of mounting the process cartridge of Example 1 on the apparatus main body Explanatory drawing of mounting the process cartridge of Example 1 on the apparatus main body Explanatory drawing of mounting the process cartridge of Example 1 on the apparatus main body Explanatory drawing of the deformation | transformation state of the apparatus main body of the image forming apparatus which concerns on Example 1. FIG. Explanatory drawing of engagement with the apparatus main body of the process cartridge of Example 1 1 is a schematic cross-sectional view of an image forming apparatus according to a first embodiment. Schematic view of the periphery of the non-driving side support portion viewed from the inside of the apparatus main body in the first embodiment. 1 is a schematic cross-sectional view of an image forming apparatus according to an embodiment of the present invention. Schematic of the non-driving side plate of the image forming apparatus main body according to the second embodiment. Explanatory drawing of engagement with the apparatus main body of the process cartridge of Example 2

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be exemplarily described in detail with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in this embodiment should be appropriately changed according to the configuration of the apparatus to which the invention is applied and various conditions. That is, it is not intended to limit the scope of the present invention to the following embodiments.

Example 1
An image forming apparatus according to a first embodiment of the present invention will be described with reference to FIGS. Examples of the image forming apparatus to which the present invention can be applied include an electrophotographic copying machine, an electrophotographic printer (such as an LED printer and a laser beam printer), a facsimile machine, and a word processor. In the following description, the rotational axis direction of the electrophotographic photosensitive drum is the longitudinal direction. In the longitudinal direction, the side to which the electrophotographic photosensitive drum transmits the driving force from the image forming apparatus main body is defined as the driving side, and the opposite side is defined as the non-driving side.

  The overall configuration of the image forming apparatus and the image forming process will be described with reference to FIGS. FIG. 1 is a schematic cross-sectional view of an image forming apparatus main body (hereinafter referred to as apparatus main body A) and a process cartridge (hereinafter referred to as cartridge B) of an image forming apparatus according to Embodiment 1 of the present invention. FIG. 2 is a schematic cross-sectional view of the cartridge B. Here, the apparatus main body A is a portion excluding the cartridge B in the apparatus configuration of the image forming apparatus.

<Entire configuration of electrophotographic image forming apparatus>
The image forming apparatus shown in FIG. 1 is a laser beam printer using an electrophotographic technique in which a cartridge B is detachable from an apparatus main body A. When the cartridge B is mounted on the apparatus main body A, an exposure device 3 (laser scanner unit) for forming a latent image on the electrophotographic photosensitive drum 62 as an image carrier of the cartridge B is disposed. In addition, a sheet tray 4 that stores a recording material (hereinafter referred to as a sheet material P) that is an image forming target is disposed below the cartridge B. Further, the apparatus main body A includes a pickup roller 5a, a feeding roller pair 5b, a conveyance roller pair 5c, a transfer guide 6, a transfer roller 7, a conveyance guide 8, a fixing device 9, along the conveyance direction D of the sheet material P. A pair of discharge rollers 10, a discharge tray 11, and the like are sequentially arranged. The fixing device 9 includes a heating roller 9a and a pressure roller 9b. When the image forming apparatus described above is packaged and shipped as a product, the image forming apparatus may be packed with a process cartridge mounted in the apparatus main body in order to reduce the packing form.

<Image formation process>
Next, an outline of the image forming process will be described. Based on the print start signal, the electrophotographic photosensitive drum (hereinafter referred to as drum 62) is rotationally driven in the direction of arrow R with a predetermined peripheral speed (process speed). The charging roller 66 to which the bias voltage is applied contacts the outer peripheral surface of the drum 62 and uniformly charges the outer peripheral surface of the drum 62. The exposure device 3 outputs a laser beam L corresponding to the image information. The laser light L passes through a laser opening 71 h provided in the cartridge B, and scans and exposes the outer peripheral surface of the drum 62. As a result, an electrostatic latent image corresponding to the image information is formed on the outer peripheral surface of the drum 62.

  On the other hand, as shown in FIG. 2, in the developing unit 20 as a developing device, the toner T in the toner chamber 29 is agitated and conveyed by the rotation of the conveying member 43 and sent out to the toner supply chamber 28. The toner T is carried on the surface of the developing roller 32 by the magnetic force of the magnet roller 34 (fixed magnet). While the toner T is frictionally charged by the developing blade 42, the layer thickness on the circumferential surface of the developing roller 32 as a developer carrying member is regulated. The toner T is developed on the drum 62 in accordance with the electrostatic latent image, and is visualized as a toner image.

  Further, as shown in FIG. 1, the sheet material P stored in the lower part of the apparatus main body A is moved to the sheet tray by the pickup roller 5a, the feeding roller pair 5b, and the conveying roller pair 5c in accordance with the output timing of the laser beam L. 4 is sent out. Then, the sheet material P is conveyed to the transfer position between the drum 62 and the transfer roller 7 via the transfer guide 6. At this transfer position, the toner images are sequentially transferred from the drum 62 to the sheet material P. The sheet material P to which the toner image has been transferred is separated from the drum 62 and conveyed to the fixing device 9 along the conveyance guide 8. The sheet material P passes through the nip portion between the heating roller 9a and the pressure roller 9b constituting the fixing device 9. A pressure / heat fixing process is performed in the nip portion, and the toner image is fixed on the sheet material P. The sheet material P that has undergone the toner image fixing process is conveyed to the discharge roller pair 10 and discharged to the discharge tray 11.

  On the other hand, as shown in FIG. 2, the drum 62 after transfer is used again in the image forming process after the residual toner on the outer peripheral surface is removed by the cleaning blade 77. The toner removed from the drum 62 is stored in a waste toner chamber 71b of a cleaning unit 60 as a frame having a photosensitive drum.

<Configuration of the entire cartridge>
The overall configuration of the cartridge B will be described with reference to FIGS. 2, 3, and 4. 3 and 4 are perspective views for explaining the configuration of the cartridge B. FIG. In the present embodiment, the screws for connecting the parts will be omitted.

The cartridge B has a cleaning unit 60 and a developing unit 20. In general, the process cartridge is an electrophotographic photosensitive member and at least one of a charging unit, a developing unit, and a cleaning unit as a process unit that acts on the electrophotographic photosensitive member. The main body A is detachable. The process cartridge in this embodiment has at least the following cleaning unit 60.

  As shown in FIG. 2, the cleaning unit 60 includes a drum 62, a charging roller 66, a cleaning member 77, and a cleaning frame body 71 as a frame body that supports them. In the cleaning unit 60, the charging roller 66 and the cleaning member 77 are disposed in contact with the outer peripheral surface of the drum 62. The cleaning member 77 includes a rubber blade 77a that is a blade-like elastic member formed of rubber as an elastic material, and a support member 77b that supports the rubber blade. The rubber blade 77 a is in contact with the drum 62 in the counter direction with respect to the rotation direction of the drum 62. That is, the rubber blade 77 a is in contact with the drum 62 so that the tip end portion thereof faces the upstream side in the rotation direction of the drum 62.

  As shown in FIG. 2, the waste toner removed from the surface of the drum 62 by the cleaning member 77 is stored in a waste toner chamber 71 b formed by the cleaning frame 71 and the cleaning member 77. In addition, a squeeze sheet 65 for preventing waste toner from leaking from the cleaning frame 71 is provided at the edge of the cleaning frame 71 so as to contact the drum 62. The drum 62 is rotationally driven in the direction of arrow R in the drawing according to an image forming operation by receiving a driving force from a main body driving motor (not shown) as a driving source. The charging roller 66 is rotatably attached to the cleaning unit 60 via charging roller bearings (not shown) at both ends in the longitudinal direction of the cleaning frame 71. The charging roller 66 is provided with a charging roller bearing. The pressure roller 68 is pressed against the drum 62 by being pressed toward the drum 62. The charging roller 66 rotates following the rotation of the drum 62.

As shown in FIG. 2, the developing unit 20 includes a developing roller 32, a developing container 23 that supports the developing roller 32, a developing blade 42, and the like. A magnet roller 34 is provided in the developing roller 32. In the developing unit 20, a developing blade 42 for restricting the toner layer on the developing roller 32 is disposed.
As shown in FIGS. 3 and 4, a spacing member 38 is attached to the developing roller 32 at both ends of the developing roller 32, and the spacing roller 38 and the drum 62 abut so that the developing roller 32 is a drum. 62 and a slight gap.
Further, as shown in FIG. 2, a blowout prevention sheet 33 for preventing toner from leaking from the developing unit 20 is provided at the edge of the bottom member 22 so as to contact the developing roller 32. Further, a transport member 43 is provided in the toner chamber 29 formed by the developing container 23 and the bottom member 22. The conveying member 43 agitates the toner stored in the toner chamber 29 and conveys the toner to the toner supply chamber 28.

As shown in FIGS. 3 and 4, the cartridge B is configured by combining a cleaning unit 60 and a developing unit 20. The cleaning unit 60 is provided with a cleaning frame 71, a drum 62, and a drum bearing 73 and a drum shaft 78 for rotatably supporting the drum 62.
As shown in FIG. 3, on the drive side, the drum 62 is rotatably supported by a drive-side drum flange 63 provided on the drive side by a hole 73 a of a drum bearing 73. The drum bearing 73 is provided with a positioning projection 74 which is a positioning portion for determining the position of the cartridge B in the longitudinal direction with respect to the apparatus main body A.
As shown in FIG. 4, on the non-driving side, a drum shaft 78 press-fitted into a hole 71c provided in the cleaning frame 71 rotatably supports a hole (not shown) of a non-driving side drum flange. It is the composition to do. Further, a recess 75 that prevents the cartridge B from falling off from the apparatus main body A is provided on the side surface of the cleaning frame 71.
FIG. 5 is a perspective view for explaining the details of the recess 75. As shown in the figure, the recess 75 includes a first surface 75a that is a circumferential surface coaxial with the rotation axis direction of the drum 62, and a second surface 75b that extends substantially at right angles (substantially horizontal) to the rotation axis direction. Yes. In addition, an opening 75c is provided in the mounting direction (described later) of the cartridge B with respect to the apparatus main body A. Further, the concave portion 75 is a pair of third counters that are opposed to each other around the rotation axis as a restriction portion that restricts relative movement of the drum 62 between the process cartridge B and a protrusion 16e described later in a direction orthogonal to the rotation axis direction. A surface 75d is provided as a restriction surface for the relative movement. That is, the concave portion 75 has a concave shape corresponding to the shape of the protrusion 16e described later.

As shown in FIGS. 2, 3, and 4, the developing unit 20 includes a bottom member 22, a developing container 23, a driving side developing side member 26, a developing blade 42, a developing roller 32, and the like. The developing roller 32 is rotatably attached to the developing container 23 by bearing members 27 and 37 provided at both ends. The developing unit 20 and the cleaning unit 60 are assembled as indicated by an arrow G shown in FIGS. The development first support boss 23a and the development second support boss 23b of the developer container 23 are fitted in the first suspension hole 71i and the second suspension hole 71j of the cleaning frame 71, respectively. Thereby, the developing unit 20 is rotatably connected to the cleaning unit 60.
Between the cleaning unit 60 and the developing unit 20, a driving side biasing member 46L (FIG. 3) and a non-driving side biasing member 46R (FIG. 4) are provided. By this urging force, the developing unit 20 is urged toward the cleaning unit 60, and the developing roller 32 is pressed toward the drum 62. The developing roller 32 is held at a predetermined interval from the drum 62 by a spacing holding member 38 attached to both ends of the developing roller 32.

<Installation and support of cartridge>
The mounting of the cartridge B to the apparatus main body A will be described with reference to FIGS. The state of mounting on the drive side will be described with reference to FIGS. FIG. 6 is a perspective view of the apparatus main body A and the cartridge B when the opening / closing door 13 is opened and the cartridge B is mounted. The cartridge B can be attached to and detached from the apparatus main body A in the direction of arrow C in the figure. The apparatus main body A includes a driving side plate 15 and a non-driving side plate 16 as a pair of side plate portions that support the cartridge B and that face each other as a part of the frame. Both ends of the cartridge B are engaged with the driving side plate 15 and the non-driving side plate 16 provided in the driving side plate 15 and the non-driving side plate 16, respectively, and are engaged with the support portions that are recessed in the opposing direction of the driving side plate 15 and the non-driving side plate 16. Supported by the side plate 16.

  As shown in FIG. 6, on the drive side of the apparatus main body A, a drive side plate 15, which is a support member that supports the cartridge B, is provided as one side plate portion. The driving side plate 15 is provided with a driving side first rail 15a, a driving side support portion 15b, a driving side second rail 15c, and a rotation stop portion 15d. Further, an engagement hole 15e is provided as a main body positioning portion that determines the position of the cartridge B in the longitudinal direction. Further, a drive member 14 for transmitting drive from the apparatus main body A to the cartridge B is provided.

As shown in FIG. 3, as a supported portion of the cartridge B, the drum bearing 73 is provided with a supported portion 73 b and a driving side boss 73 c. When the cartridge B is mounted on the apparatus main body A, the supported portion 73b and the driving boss 73c of the cartridge B are guided by the driving side first rail 15a and the driving side second rail 15c of the apparatus main body A, respectively. Installed.
FIG. 7 is a schematic diagram illustrating a state where the cartridge B is mounted on the apparatus main body A. In the figure, some parts are omitted for explanation. As shown in the figure, on the drive side of the cartridge B, the supported portion 73b is engaged with and supported by the drive side support portion 15b, and the drive side boss 73c abuts against the rotation stop portion 15d to determine the position in the rotation direction. . Further, the positioning protrusion 74 of the cartridge B is inserted into the engagement hole 15 e of the apparatus main body A. Thereby, the longitudinal position of the cartridge B with respect to the apparatus main body A is determined.

The driving member 14 of the apparatus main body A is engaged with the engaging portion 70 (see FIG. 3) of the cartridge B,
Drive is transmitted from the apparatus main body A to the cartridge B.

  The state of mounting on the non-driving side will be described with reference to FIGS. FIG. 8 is a perspective view seen from the opposite side of FIG. As shown in FIG. 8, a non-driving side plate 16 that is a support member that supports the cartridge B is provided on the non-driving side of the apparatus main body A as the other side plate portion. The non-driving side plate 16 is provided with a non-driving side first rail 16a, a non-driving side support portion 16b, and a non-driving side second rail 16c. Further, as a drop-off preventing portion, a protrusion 16e is provided that protrudes toward the inside of the apparatus main body A in the rotation axis direction of the drum 62 (opposite direction of the driving side plate 15 and the non-driving side plate 16).

As shown in FIG. 4, the cleaning frame 71 is provided with a non-driving side positioning projection 71d and a non-driving side boss 71g. When the cartridge B is mounted on the apparatus main body A, the non-driving side positioning protrusion 71d and the non-driving side boss 71g of the cartridge B guide the non-driving side first rail 16a and the driving side second rail 16c of the apparatus main body A, respectively. Is done.
FIG. 9 is a schematic diagram illustrating a state where the cartridge B is mounted on the apparatus main body A. In the figure, some parts are omitted for explanation. As shown in the drawing, the non-driving side positioning projection 71d of the cartridge B engages with the non-driving side support portion 16b of the apparatus main body A and is positioned and supported.

  Further, the protrusion 16e of the apparatus main body A is arranged so as to be positioned in the recess 75 of the cartridge B.

  The configuration of the recess 75 of the cartridge B and the protrusion 16e of the apparatus main body A will be described in detail with reference to FIG. FIG. 10 is a schematic cross-sectional view showing a schematic configuration around the recess 75 of the cartridge B. As shown in FIG. As shown in the figure, in the rotation axis direction U of the drum 62, the second protrusion surface 16e2 constituting the protrusion 16e of the apparatus main body A faces the second surface 75b constituting the recess 75 of the cartridge B. Further, in the direction orthogonal to the rotation axis direction U of the drum 62, the first projection surface 16e1 constituting the projection 16e of the apparatus main body A faces the first surface 75a constituting the recess 75 of the cartridge B.

  Finally, the opening / closing door 13 is closed, and the mounting of the cartridge B to the apparatus main body A is completed. As described above, when an image forming apparatus is packaged and shipped as a product, the image forming apparatus may be packaged with the process cartridge B mounted in the apparatus main body A in order to reduce the packing form. When the product is transported in this state, the apparatus main body A may be temporarily deformed by vibration or impact.

  A state when the apparatus main body A is deformed by an impact or the like will be described with reference to FIGS. 11 and 12. FIG. 11 is a schematic diagram showing one form of deformation when the apparatus main body A receives an impact or the like. In the figure, some parts are omitted for explanation. As shown in FIG. 11, the driving side plate 15 and the non-driving side plate 16 may be in a state where their substantially central portions are deformed outward (in the direction of arrow H in the figure) due to the impact received by the apparatus main body A, respectively. . As a result, the facing distance between the driving side plate 15 and the non-driving side plate 16 changes, and the rotation axis direction of the drum 62 between the driving side plate 15 and the non-driving side plate 16 and the cartridge B (the facing of the driving side plate 15 and the non-driving side plate 16). The relative position in (direction) will change.

12A and 12B are schematic diagrams of the driving side and the non-driving side in a state where the driving side plate 15 and the non-driving side plate 16 of the apparatus main body A are deformed, respectively. In the figure, some parts are omitted for explanation.
As shown in FIG. 12A, on the driving side, the positioning projection 74 of the cartridge B enters the engaging hole 15e provided in the driving side plate 15 of the apparatus main body A. Follow the deformation. Therefore, the supported portion 73b is continuously supported by the drive side support portion 15b of the drive side plate 15. That is, the drive side plate 15 and the cartridge B are configured such that relative movement of the drum 62 in the rotation axis direction is restricted.
As shown in FIG. 12B, on the non-driving side, the movement following the deformation of the non-driving side plate 16 of the apparatus main body A and the deformation of the driving side plate 15 of the cartridge B described with reference to FIG. The space between the non-drive side plate 16 and the cartridge B is widened. In the figure, the non-driving side positioning projection 71d, which is one end of the cartridge B, is pulled out from the non-driving side support portion 16b of the non-driving side plate 16 due to deformation, that is, the projection 71d is detached from the non-driving side support portion 16b. It is in the state.

  However, according to the configuration of the present embodiment, the first surface 75a constituting the concave portion 75 of the cartridge B and the first projection surface 16e1 constituting the projection portion 16e of the apparatus main body A abut. In other words, the protrusion 71d that is disengaged from the non-driving side support portion 16b is supported by the protrusion portion 16e provided below the non-driving side support portion 16b. As shown in FIG. 12B, the protrusion 16e (first protrusion surface 16e1) includes an inclined surface that inclines downward from a support surface that supports the lower portion of the protrusion 71d in the non-driving side support portion 16b, And a surface extending in the drum rotation axis direction as a drop-off preventing surface first from the inclined surface. When the impact on the apparatus main body A is settled, the deformation of the driving side plate 15 and the non-driving side plate 16 returns, and the distance between the non-driving side plate 16 and the cartridge B returns to the original state. At this time, the first surface 75a of the cartridge B is relatively moved so as to be guided along the first projection surface 16e1 of the non-driving side plate 16, and the non-driving side positioning projection 71d of the cartridge B is moved to the non-driving side plate 16. Re-engage with the non-driving side support 16b. That is, it returns to the state shown in FIG.

  According to the above configuration, the cartridge B can be prevented from dropping from a predetermined position of the apparatus main body A even if the apparatus main body A is deformed by an impact or the like. Further, there may be a thin plate-like member or the like in the space S between the first surface 75a of the cartridge B and the first projecting surface 16e1 of the non-driving side plate 16 (see FIG. 10). The non-driving side positioning projection 71d of the cartridge B is guided with these members sandwiched therebetween, and is reengaged with the non-driving side support portion 16b of the non-driving side plate 16.

  FIG. 13 is a schematic cross-sectional view of the image forming apparatus when the open / close door 13 is closed. As shown in the figure, the cartridge B is urged in the direction of arrow F by the urging member 12 provided in the apparatus main body A via the cartridge pressing member 1 provided in the opening / closing door 13. The cartridge pressing member 1 is assembled to the opening / closing door 13 so as to be rotatable about a rotation shaft 1a (see FIG. 1). The urging force received by the cartridge B acts in a direction in which the cartridge B is pressed against the driving side support portion 15b, the rotation stop portion 15d, and the non-driving side support portion 16b of the apparatus main body A. (See FIGS. 7 and 9) By doing so, the cartridge B is stably positioned and held in the apparatus main body A.

  The force and protrusion 16e that act on the non-driving side support portion 16b of the apparatus main body A from the cartridge B by the cartridge pressing member 1 (not shown) will be described with reference to FIG. FIG. 14 is a schematic view of the periphery of the non-driving side support portion 16b as viewed from the inside of the apparatus main body A, and some components are omitted for the sake of explanation. In FIG. 14, the force that the urging force from the apparatus main body A acts on the non-driving side support portion 16b of the non-driving drive plate 16 from the non-driving side positioning projection 71d of the cartridge B is indicated by an arrow F2. As shown in FIG. 14, in the present embodiment, the first projection surface 16e1 of the projection 16e is provided in the direction of F2 action. By doing so, the first surface 75a of the cartridge B is reliably pressed against the first projecting surface 16e1 of the non-driving side plate 16 when the apparatus main body A receives an impact or the like and the side plate is deformed. . Therefore, when the deformation of the apparatus main body A returns, the relative movement of the first surface 75a of the cartridge B along the first projecting surface 16e1 of the non-driving side plate 16 is performed reliably, and the cartridge B is more reliably prevented from falling off. it can.

As shown in FIG. 15, the fixing device 9 of the apparatus main body A is provided above the rotation axis V of the drum 62 of the cartridge B, and the protrusion 16 e of the apparatus main body A is below the rotation axis V of the drum 62. That is, it is provided far away. The fixing device 9 is fixed to the driving side member and the non-driving side member of the apparatus main body A with screws or the like. In this configuration, the fixing device 9 also functions as a reinforcing structural member of the apparatus main body A. When the apparatus main body A receives an impact or the like, the deformation of the non-drive side plate 16 and the drive side plate 15 causes the drum 62 of the cartridge B to be deformed. The upper side of the rotation axis V is smaller and increases as it goes downward. In this embodiment, since the protrusions 16e are provided over the lower part of the rotation axis V of the drum 62, the deformation of both side plates is increased, which is more effective in preventing the dropout.

  As described above, in the image forming apparatus according to the present embodiment, the process cartridge B is dropped even when the apparatus main body A is deformed when the process main body B is transported in the apparatus main body A. Can be prevented.

(Example 2)
A second embodiment of the present invention will be described with reference to FIGS. In the present embodiment, parts different from the above-described embodiment will be described in detail. Unless otherwise noted, the material, shape, etc. are the same as in the previous embodiment. Such parts are given the same numbers and will not be described in detail.

  FIG. 16 is a perspective view of the non-drive side plate 116 of the apparatus main body A according to the second embodiment of the present invention. As shown in FIG. 16, in the present embodiment, the first protrusion surface 116e1 constituting the protrusion 116e provided on the non-driving side plate 116 and the non-driving side support portion 116b are formed on the same surface. That is, the drop-off prevention surface of the protrusion 116e of the present embodiment is configured to extend in the drum rotation axis direction continuously with the support surface that supports the lower portion of the protrusion 71d in the non-driving side support portion 116b.

  FIGS. 17A and 17B are schematic diagrams for explaining details of the protrusion 116e. In the figure, some parts are omitted for explanation. FIG. 17A shows a state in which the cartridge B is attached to the apparatus main body A, and a state in which the non-driving side positioning projection 71d is engaged with the non-driving side support portion 116b. FIG. 17B shows the engaged state of the non-driving side plate 116 and the cartridge B when the both side plates are deformed as shown in FIG. As shown in FIG. 17B, the non-driving side plate 116 and the non-driving side plate 116 are deformed by the deformation of the non-driving side plate 116 of the apparatus main body A and the movement following the deformation of the driving side plate 15 of the cartridge B described in FIG. The space between the cartridge B is widened. In the figure, the non-driving side positioning projection 71d of the cartridge B is pulled out from the non-driving side support portion 116b of the non-driving side plate 116 due to deformation.

  However, according to the configuration of the present embodiment, the first surface 75a constituting the concave portion 75 of the cartridge B and the first projection surface 116e1 constituting the projection 16e of the apparatus main body A abut. When the deformation of the apparatus main body A returns, the first surface 75a of the cartridge B moves so as to slide relatively along the first projection surface 116e1 of the non-drive side plate 116, and the non-drive side positioning projection 71d of the cartridge B moves. The non-driving side plate 116 is engaged again with the non-driving side support 116b.

  According to the present embodiment, since the first projection surface 116e1 and the non-driving side support portion 116b are configured as the same surface, the first surface 75a of the cartridge B slides along the first projection surface 116e1. There is no step in the process of returning to the non-driving side support portion 116b. Therefore, the non-driving side positioning protrusion 71d of the cartridge B is smoothly engaged with the non-driving side support portion 116b without being caught.

According to the above configuration, even if the apparatus main body A is deformed by an impact or the like, the cartridge B is not attached to the apparatus main body A.
Can be prevented from falling off from a predetermined position. Therefore, in the image forming apparatus according to the present embodiment, when the apparatus main body A is transported with the process cartridge B mounted, the process cartridge B can be prevented from dropping even if the apparatus main body A is deformed. it can.

  DESCRIPTION OF SYMBOLS 15 ... Drive side plate, 15b ... Drive side support part, 16 ... Non drive side plate, 16b ... Non drive side support part, 16e ... Projection, 71 ... Cleaning frame, 71d ... Non drive side positioning protrusion, 73b ... Supported part, A: Image forming apparatus main body (apparatus main body), B: Process cartridge (cartridge)

Claims (13)

An image forming apparatus for forming an image on a recording material,
An apparatus main body having a pair of side plate portions facing each other;
A process cartridge that is attachable to and detachable from the apparatus main body, and is supported by the pair of side plate portions by engaging both ends with support portions respectively provided on the pair of side plate portions;
In an image forming apparatus comprising:
One side plate portion of the pair of side plate portions is disengaged from the support portion of the one side plate portion due to a change in relative position in the facing direction between the pair of side plate portions and the process cartridge. An image forming apparatus comprising a drop-off prevention unit capable of supporting an end portion.   2. The image forming apparatus according to claim 1, wherein the drop-off prevention unit is a projection that protrudes in the facing direction and is provided so as to be continuous with the support in the one side plate.   3. The projecting portion includes an inclined surface that is inclined from a support surface that supports the end portion in the support portion, and a drop-off preventing surface that extends in the opposite direction first from the inclined surface. The image forming apparatus described in 1.   The inclined surface has a relative position between the process cartridge and the one side plate portion from a first relative position where the end portion does not engage with the support portion of the one side plate portion, and the end portion is the one of the one side plate portion. The image forming apparatus according to claim 3, wherein the end portion is guided to the support portion when the side plate portion is changed to a second relative position that engages with the support portion.   3. The image forming apparatus according to claim 2, wherein the protrusion has a drop-off preventing surface that extends in the facing direction and is connected to a support surface that supports the end portion in the support portion.   The apparatus main body further includes a biasing member that imparts a biasing force to the process cartridge in a direction in which the end portion removed from the support portion is engaged with the protrusion. The image forming apparatus according to claim 5. The apparatus main body includes a fixing device that fixes a toner image formed on the recording material to the recording material,
The image forming apparatus according to claim 2, wherein the process cartridge is mounted such that the protruding portion is further from the fixing device than a rotation shaft of the photosensitive drum. .   The image forming apparatus according to claim 1, wherein the process cartridge includes a restricting portion that restricts relative movement between the protrusion and the protrusion in a direction orthogonal to the facing direction. .   The image forming apparatus according to claim 8, wherein the process cartridge includes a recessed portion having a recessed shape corresponding to the shape of the protruding portion as the restricting portion.   The other side plate portion of the pair of side plate portions and the process cartridge are configured such that relative movement in the facing direction is restricted. The image forming apparatus described. The process cartridge includes a photosensitive drum, and a driving force for rotating the photosensitive drum is on the side of an end portion engaged with the support portion of the other side plate portion of the pair of side plate portions.
The image forming apparatus according to claim 1, wherein the image forming apparatus transmits the image from the apparatus main body.   The change in the relative position in the facing direction between the pair of side plate portions and the process cartridge is caused by deformation of the pair of side plate portions in which an interval at which the pair of side plate portions face each other is changed. Item 12. The image forming apparatus according to any one of Items 1 to 11. A process cartridge that is detachable from an apparatus main body of an image forming apparatus that forms an image on a recording material,
In the process cartridge supported by the pair of side plates by engaging both ends with support portions respectively provided on a pair of side plates facing each other in the apparatus main body,
Due to a change in the relative position in the facing direction between the pair of side plate portions and the process cartridge, the end portion that is detached from the support portion of the one side plate portion becomes the support portion in the one side plate portion. It is configured to be supported by a protrusion protruding in the opposing direction provided,
A process cartridge having a recessed portion having a recessed shape corresponding to the shape of the protruding portion so as to restrict relative movement between the protruding portion and a direction orthogonal to the facing direction.