JP2010091988A - Process cartridge - Google Patents

Abstract

A process cartridge capable of preventing erroneous mounting of a developing unit is provided.
A process cartridge includes a photosensitive unit having a photosensitive drum, and a developing unit having a developing roller and detachably attached to the photosensitive unit. The photoreceptor unit 51 is provided with an urging member 200 that swings in a direction toward and away from the developing unit 61. The biasing member 200 is attached to the developing unit 61 when it is correctly attached to the photoreceptor unit 51. A protrusion 100 is provided that slides on the biasing member 200 to swing the biasing member 200 away from the developing unit 61. In the process cartridge 50, when the developing unit 63 is mounted on the photosensitive unit 51 at a position where the developing roller 63 is not correct with respect to the photosensitive drum 53, the protruding portion 100 is caught by the biasing member 200.
[Selection] Figure 3

Description

  The present invention relates to a process cartridge used in an image forming apparatus such as a color printer.

  In general, a process cartridge used in an image forming apparatus such as a color printer has a photosensitive unit having a photosensitive drum on which an electrostatic latent image is formed, and a developing roller for supplying toner to the photosensitive drum. A device including a developing unit that is detachably attached to a body unit is known (for example, see Patent Document 1).

  In such a process cartridge, the developing roller shaft is inserted into a positioning groove provided on the side wall of the photosensitive unit, and the developing unit main body is placed in a concave housing portion formed by the side wall, rear wall, and bottom wall of the photosensitive unit. , The developing unit is attached to the photoreceptor unit.

JP 2008-203666 A (FIG. 2)

  By the way, as the photosensitive unit to which the developing unit is detachably mounted, a step in which the latter is lower between a portion of the side wall located on both sides of the photosensitive drum and a portion adjacent to the positioning groove. There is a thing of the shape which has. When the developing unit is attached to or detached from such a photosensitive unit, the developing unit main body is accommodated in the photosensitive unit housing in a state where the shaft of the developing roller is not inserted into the positioning groove and is supported by the step. There was a case.

  At this time, if the user recognizes that the developing unit is correctly attached, the user next tries to attach the process cartridge to the image forming apparatus. However, since the developing unit is not actually mounted correctly, the process cartridge cannot be mounted on the image forming apparatus, and the user has to remove the developing unit from the photosensitive unit and mount it again.

  SUMMARY An advantage of some aspects of the invention is that it provides a process cartridge that can prevent erroneous mounting of a developing unit.

  In order to achieve the above-described object, a process cartridge according to the present invention includes a photosensitive unit having a photosensitive member on which an electrostatic latent image is formed, and a developer carrier for supplying a developer to the photosensitive member. A development cartridge detachably attached to the photosensitive unit, wherein the photosensitive unit has a side opposite to the side where the photosensitive unit is disposed across the developing unit, A swinging member is provided that swings in a direction approaching or separating from the developing unit. When the developing unit protrudes toward the swinging member and is correctly attached to the photosensitive unit, Protruding portions are provided that slidably contact the oscillating member to oscillate the oscillating member in a direction away from the developing unit, and the developer carrier is not correct with respect to the photoconductor. In location, when the developing unit is mounted operation on the photosensitive member unit, characterized in that the protrusion is caught by the swinging member.

  According to the process cartridge configured as described above, when the developing unit is correctly mounted on the photosensitive unit, the protrusion provided on the developing unit causes the swinging member provided on the photosensitive unit to swing. By retracting, the developing unit can be attached to the photoreceptor unit. On the other hand, when the developer carrying member is mounted on the photoconductor unit at a position where the developer carrying member is not correct with respect to the photoconductor, the protruding portion is caught by the swinging member, thereby preventing erroneous mounting of the developing unit. can do.

  According to the process cartridge of the present invention, when the developer carrying member is not correctly positioned with respect to the photosensitive member and the developing unit is mounted on the photosensitive member unit, the protrusion is caught by the swinging member. Incorrect mounting of the unit can be prevented.

<Overall configuration of color printer>
Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. In the drawings to be referred to, FIG. 1 is a cross-sectional view showing an overall configuration of a color printer as an example of an image forming apparatus provided with a process cartridge of the present invention, and FIG. 2 is a cross-sectional view of the process cartridge.

  In the following description, the direction will be described based on the user who uses the color printer. That is, in FIG. 1, the left side toward the paper surface is the “front” side, the right side toward the paper surface is the “rear” side, the back side toward the paper surface is the “left” side, and the front side toward the paper surface is “right”. ”Side. In addition, the vertical direction toward the page is the “vertical” direction.

  As shown in FIG. 1, the color printer 1 includes a paper feeding unit 20 that supplies paper P, an image forming unit 30 that forms an image on the fed paper P, and an image formed in a main body housing 10. And a paper discharge unit 90 for discharging the paper P.

  A top cover 12 that can be opened and closed up and down with the rear side as a fulcrum is provided on the upper portion of the main body housing 10. The top cover 12 has an upper surface serving as a paper discharge tray 13 that accumulates the paper P discharged from the main body housing 10, and a plurality of LED holding portions 14 that hold the LED units 40 are provided on the lower surface. .

  The paper feeding unit 20 is provided in the lower part of the main body housing 10, and a paper feeding tray 21 that is detachably attached to the main body housing 10. The paper P is supplied from the paper feeding tray 21 to the image forming unit 30. The paper supply mechanism 22 is mainly provided. In the paper supply unit 20, the paper P stored in the paper supply tray 21 is separated one by one by the paper supply mechanism 22 and supplied to the image forming unit 30.

  The image forming unit 30 mainly includes four LED units 40, four process cartridges 50, a transfer unit 70, and a fixing unit 80.

  The LED unit 40 is disposed to face an upper side of a photosensitive drum 53 as an example of a photosensitive member, and is configured to expose the surface of the photosensitive drum 53. Since the LED unit 40 is fixed to the top cover 12 via the LED holding portion 14, the LED unit 40 can move together with the top cover 12.

  The process cartridge 50 is arranged side by side in the front-rear direction between the top cover 12 and the paper feed unit 20 and is detachably attached to the main body housing 10 through an opening formed when the top cover 12 is opened. . The process cartridge 50 includes a photoconductor unit 51 and a developing unit 61 that is detachably attached to the photoconductor unit 51. Each process cartridge 50 is different in only the color of toner as an example of the developer stored in the toner storage section 66 (see FIG. 2) of the developing unit 61, and has the same configuration.

  As shown in FIG. 2, the photoreceptor unit 51 mainly includes a photoreceptor case 52, a photoreceptor drum 53, and a charger 54. By attaching the developing unit 61 to the photoconductor case 52, an exposure hole 55 that faces the photoconductor drum 53 from the outside is formed. The LED unit 40 is inserted into the exposure hole 55 so as to face the photosensitive drum 53.

  The developing unit 61 mainly includes a developing case 62, a developing roller 63 as an example of a developer carrier, a supply roller 64, and a layer thickness regulating blade 65, and includes a toner container 66 that stores toner. ing.

  The developing unit 61 attached to the main body housing 10 as the process cartridge 50 is pushed upward substantially by a known mechanism provided in the main body housing 10, so that the developing roller 63 is separated from the photosensitive drum 53. However, the developing roller 63 is configured to approach (or contact) the photosensitive drum 53 when the push-up is released (see FIG. 10). Thereby, a monochrome image can be formed.

  Returning to FIG. 1, the transfer unit 70 is provided between the paper feeding unit 20 and each process cartridge 50, and mainly includes a drive roller 71, a driven roller 72, a conveyance belt 73, and a transfer roller 74. ing. The driving roller 71 and the driven roller 72 are spaced apart in parallel in the front-rear direction, and an endless conveying belt 73 is stretched between them. The outer surface of the conveyance belt 73 is in contact with each photosensitive drum 53, and a transfer roller 74 that holds the conveyance belt 73 between the photosensitive drums 53 faces the photosensitive drum 53. One is arranged. A transfer bias is applied to the transfer roller 74 during transfer.

  The fixing unit 80 is disposed behind each process cartridge 50 and the transfer unit 70, and includes a heating roller 81 and a pressure roller 82 that is disposed to face the heating roller 81 and presses the heating roller 81.

  In the image forming unit 30, the surface of the photosensitive drum 53 is uniformly charged by the charger 54 and then exposed to light emitted from the LED unit 40, whereby image data is converted onto the photosensitive drum 53. A based electrostatic latent image is formed. Further, the toner in the toner container 66 is supplied from the supply roller 64 to the developing roller 63 and enters between the developing roller 63 and the layer thickness regulating blade 65 to form a thin layer with a certain thickness on the developing roller 63. Supported.

  The toner carried on the developing roller 63 is supplied from the developing roller 63 to the electrostatic latent image on the photosensitive drum 53. As a result, the electrostatic latent image is visualized and a toner image is formed on the photosensitive drum 53. Thereafter, the paper P supplied onto the conveyance belt 73 passes between the photosensitive drum 53 and the transfer roller 74 disposed inside the conveyance belt 73, so that the toner formed on each photosensitive drum 53. The image is sequentially superimposed on the paper P and transferred. Then, as the paper P passes between the heating roller 81 and the pressure roller 82, the toner image transferred onto the paper P is thermally fixed.

  The paper discharge unit 90 mainly includes a paper discharge side transport path 91 formed so as to extend upward from the exit of the fixing unit 80 and change its direction forward, and a plurality of transport rollers 92 that transport the paper P. I have. The sheet P on which the toner image has been thermally fixed is transported along a paper discharge side transport path 91 by a transport roller 92, discharged to the outside of the main body housing 10, and accumulated in the paper discharge tray 13.

<Detailed configuration of process cartridge>
Next, a detailed configuration of the process cartridge 50 (the photoconductor unit 51 and the developing unit 61) will be described focusing on the features of the present invention. FIG. 3 is a partial cross-sectional view for explaining the configuration of the photosensitive unit and the developing unit, FIG. 4A is a perspective view of the developing unit viewed from the rear, and FIG. 3B is an enlarged view of the protruding portion. FIG. 5 is a perspective view showing the configuration of the extending portion, FIG. 6 is a perspective view of the urging member, and FIG. 7 is a perspective view of the lock member.

  In the following description, the direction will be described with reference to a state in which the process cartridge 50 is turned sideways as shown in FIG. That is, in FIG. 3, the vertical direction toward the paper surface is the “vertical” direction, the side on which the photosensitive drum 53 and the developing roller 63 are disposed is the “front” side, and the opposite side is the “rear” side. Further, the left-right direction determined based on the above-defined up-down and front-back directions is defined as a “left-right” direction.

[Development unit configuration]
As shown in FIGS. 3 and 4A, the developing unit 61 includes a pair of projecting portions 100 projecting rearward (biasing member 200) from the developing case 62 and an engaging portion 67. The rollers 63 are provided side by side in the direction (axial direction) in which the roller shaft 63A extends.

  As shown in FIGS. 3 and 4B, the protrusion 100 is formed in a mountain shape when viewed from the side, and has a contact surface 110 located on the upper side and a pressing surface 120 located on the lower side. Specifically, the protrusion 100 has an upper contact surface 110 and a lower pressing surface 120 that form a mountain shape in a side view, and a side view that constitutes the top portion 130 from both sides of the upper surface of the pressing surface 120. The shape is such that a triangular protrusion is provided.

  The abutting surface 110 is a surface with which a biasing member 200 described later abuts when the developing unit 61 is attached to the photosensitive unit 51.

  The pressing surface 120 is a surface that slidably contacts the urging member 200 and swings the urging member 200 when the developing unit 61 is correctly attached to the photoconductor unit 51. The pressing surface 120 is in a position where the upper surface is recessed from the top 130 of the protruding portion 100, and extends in a planar shape so as to incline downward toward the developing case 62 from this portion.

  The engaging portion 67 is provided between the pair of protruding portions 100 in the axial direction of the developing roller 63, and has an upper flat surface portion 67A and a lower curved surface portion 67B (see FIG. 9A). ). The engaging portion 67 engages with a lock member 400 described later when the developing unit 61 is mounted on the photosensitive unit 51.

[Configuration of photoconductor unit]
As shown in FIG. 3, the photoconductor unit 51 includes a photoconductor case 52, a photoconductor drum 53, a biasing member 200 as an example of a swing member, and a lock member 400 (see FIG. 9). Yes.

  The photoconductor case 52 constitutes a housing of the photoconductor unit 51, and rotatably supports the photoconductor drum 53, and a pair of side walls 310 (only one is shown in FIG. 3) opposed in the left-right direction; It mainly comprises a bottom wall 320 that connects the lower ends of the pair of side walls 310 and a rear wall 330 that connects the rear ends of the pair of side walls 310 and the bottom wall 320. The photosensitive case 52 includes a pair of side walls 310, a bottom wall 320, and a rear wall 330 that form a concave accommodating portion 340. The lower part of the developing unit 61 is mainly accommodated in the accommodating portion 340, so that the developing unit 61 is attached to the photosensitive unit 51.

  The side wall 310 is provided with a positioning groove 311 for guiding the roller shaft 63A of the developing roller 63 when the developing unit 61 is attached to the photosensitive unit 51 and positioning the developing roller 63 with respect to the photosensitive drum 53. . The positioning groove 311 extends obliquely downward from the opening end 312 located near the center of the side wall 310 and further extends forward.

  Further, the side wall 310 is provided with an extending portion 313 extending from the photosensitive drum 53 side toward the opening end 312 so as to be adjacent to the upper side of the positioning groove 311 and along the positioning groove 311. In the present embodiment, the extending portion 313 constitutes the upper wall of the positioning groove 311. The extending portion 313 extends on the surface (upper surface) opposite to the positioning groove 311 from the opening end 312 side (front end side) along the positioning groove 311, and then extends away from the positioning groove 311. It has a shape having a bent portion 314 bent upward.

  As shown in FIG. 5, an electrode portion 54A for supplying power to the charger 54 is provided on the distal end side of the extending portion 313 so as to protrude outward in the left-right direction. Further, an inclined surface 315 is formed on the back (left side) of the electrode portion 54A so as to incline downward in a planar shape from the bent portion 314 toward the opening end 312. Thus, when the developing unit 61 is mounted on the photosensitive unit 51, the roller shaft 63A of the developing roller 63 placed on the upper surface of the inclined surface 315 slides on the inclined surface 315 without being caught by the electrode portion 54A. Guided to the open end 312 of the groove 311 (see arrow in FIG. 5).

  The biasing member 200 is swingably supported with respect to the photosensitive member case 52, and biases the contact surface 110 of the developing unit 61 attached to the photosensitive member unit 51 forward, thereby developing roller 63. Is a member that urges the photosensitive drum 53 toward the photosensitive drum 53. The biasing member 200 corresponds to each protrusion 100 of the developing unit 61 on the side opposite to the side where the photosensitive drum 53 is disposed with the developing unit 61 interposed therebetween, that is, on the rear side of the photosensitive unit 51. One by one.

  The distance from the right biasing member 200 to the right end of the developing roller 63 (roller portion) and the distance from the left biasing member 200 to the left end of the developing roller 63 (roller portion) are approximately. Are equal. Further, the projecting portion 100 provided in the developing unit 61 is also arranged corresponding to each urging member 200. Thereby, the developing roller 63 can be urged toward the photosensitive drum 53 with a uniform force.

  As shown in FIGS. 3 and 6, the urging member 200 is mainly composed of a shaft engaging portion 210, an arm portion 220, and a convex portion 230, and is moved forward (close to the developing unit 61) by a spring member (not shown). Is biased toward the direction of

  The shaft engaging portion 210 is a portion that is rotatably engaged with a cylindrical shaft portion 331 that is provided on the rear wall 330 of the photoconductor case 52 and extends in the left-right direction. When the shaft engaging portion 210 is engaged with the shaft portion 331, the urging member 200 can swing in the direction approaching / separating from the developing unit 61 (front-rear direction).

  The arm portion 220 extends upward from the shaft engaging portion 210, and on both the left and right sides on the shaft portion 331 side (lower portion), when the developing roller 63 is separated from the photosensitive drum 53, the protruding portion of the developing unit 61. A second recess 222 is provided to receive 100 tops 130 (see FIG. 10).

  The convex portion 230 is formed in a triangular shape in a side view projecting forward from the distal end side (upper portion) of the arm portion 220, and is a sliding contact portion 231 whose front surface is inclined obliquely downward from the upper portion. The sliding contact portion 231 is a portion that is in sliding contact with the pressing surface 120 of the protruding portion 100 provided in the developing unit 61 when the developing unit 61 is correctly attached to the photoreceptor unit 51.

  The convex portion 230 is formed narrower in the left-right direction than the arm portion 220, and the left and right sides of the protruding portion 100 of the developing unit 61 when the developing unit 61 is correctly attached to the photosensitive unit 51 are formed. A first recess 221 that is recessed from the sliding contact portion 231 that avoids the top portion 130 is provided. Further, on both the left and right sides of the upper end of the arm part 220, planar hooking parts 223 are provided. The function of the hooking unit 223 will be described later.

  As shown in FIG. 7, the lock member 400 is supported so as to be swingable with respect to the photoreceptor case 52, and engages with an engaging portion 67 of the developing unit 61 attached to the photoreceptor unit 51, thereby developing the lock member 400. This is a member that locks the unit 61 so as not to be detached from the photosensitive unit 51. The lock member 400 mainly includes a shaft engaging portion 410, an arm portion 420, and an operation portion 430, and is biased forward by a spring member (not shown).

  The shaft engaging portion 410 is a portion that rotatably engages with a cylindrical shaft portion 332 (see FIG. 9) that is provided on the rear wall 330 of the photoconductor case 52 and extends in the left-right direction. When the shaft engaging portion 410 is engaged with the shaft portion 332, the lock member 400 can swing in the front-rear direction.

  The arm portion 420 is a portion extending upward from the shaft engaging portion 410, and a notch portion 421 is provided on the left side so as to be sandwiched between the shaft engaging portion 410 and the operation portion 430. The developing unit 61 attached to the photoconductor unit 51 is locked so as not to be detached from the photoconductor unit 51 when the engaging portion 67 (the flat surface portion 67A) engages with the upper surface portion 422 of the notch portion 421 (see FIG. (See FIG. 9B).

  The operation portion 430 extends rearward and obliquely upward with respect to the arm portion 420, and the upper surface 431 is pushed by the curved surface portion 67B of the engaging portion 67 provided in the developing unit 61 when the developing unit 61 is correctly mounted. It is a part and a part which a user operates at the time of lock release. When the lock is released, the user pushes down the upper surface 431 of the operation unit 430 downward, so that the lock member 400 (arm unit 420) swings backward. As a result, the engagement (lock) between the engaging portion 67 and the upper surface portion 422 is released, so that the developing unit 61 can be detached from the photoreceptor unit 51.

<Effect>
The operational effects of the process cartridge 50 configured as described above will be described.
[Operation when developing unit is installed]
First, the operation when the developing unit 61 is correctly attached to the photosensitive unit 51 will be described. FIG. 8 is a view for explaining the operation of the urging member when the developing unit is correctly attached to the photosensitive unit. FIG. 8A is a view showing a state before the urging member swings. It is a figure (b) which shows a mode that a urging member rocks back.

  As shown in FIG. 8A, when the roller shaft 63A of the developing roller 63 of the developing unit 61 is inserted into the positioning groove 311 provided in the side wall 310 of the photosensitive unit 51, first, the developing unit 61 The pressing surface 120 of the protrusion 100 provided and the sliding contact portion 231 of the urging member 200 provided in the photoconductor unit 51 come into contact with each other.

  When the roller shaft 63A is further inserted into the positioning groove 311, the developing unit 61 moves (rotates) about the roller shaft 63A in the counterclockwise direction as shown in the figure, and as shown in FIG. The surface 120 and the sliding contact portion 231 (the front end portion thereof) are in sliding contact, the sliding contact portion 231 is pushed rearward by the pressing surface 120, and the urging member 200 swings backward (in a direction away from the developing unit 61). As a result, the urging member 200 is retracted rearward, so that the developing unit 61 is accommodated in the accommodating portion 340 formed in the photoreceptor case 52 of the photoreceptor unit 51 and attached to the photoreceptor unit 51.

  In addition, while the pressing surface 120 and the sliding contact portion 231 are in sliding contact, the top portion 130 of the projecting portion 100 is in a state where it does not contact the first concave portions 221 provided on the left and right sides of the convex portion 230 of the urging member 200. pass. In this way, the pressing surface 120 that is recessed from the top portion 130 and the sliding contact portion 231 are in sliding contact, and the first recess portion 221 that avoids the top portion 130 is provided, so that the top portion 130 and the biasing member 200 are directly slid. Compared with the configuration in which the urging member 200 is swung in contact with the urging member 200, the amount of rocking of the urging member 200 to the rear can be reduced. Thus, the reaction force from the spring member that urges the urging member 200 toward the front can be reduced, so that the force for swinging the urging member 200 can be reduced, and development with respect to the photoconductor unit 51 can be performed. The unit 61 can be mounted with a relatively small force.

  As shown in FIG. 3, when the developing unit 61 is mounted on the photosensitive unit 51, the front end portion of the convex portion 230 (sliding contact portion 231) of the urging member 200 is caused to protrude by the action of a spring member (not shown). The developing unit 61 is urged forward by abutting against the abutting surface 110 of the 100, and the developing roller 63 is urged toward the photosensitive drum 53. As a result, the toner carried on the developing roller 63 can be uniformly and satisfactorily supplied to the photosensitive drum 53.

  Next, the operation of the lock member 400 and the effect of the second recess 222 will be briefly described. FIG. 9 is a view for explaining the operation of the lock member when the developing unit is correctly attached to the photosensitive unit. FIG. 9A is a diagram illustrating the state in which the lock member is swung by the engaging portion. It is a figure (b) which shows a mode that the joint part and the locking member engaged. FIG. 10 is a diagram showing the positional relationship between the swing member and the protrusion when the developing roller is separated from the photosensitive drum.

  As shown in FIG. 9A, when the developing unit 61 is attached to the photosensitive unit 51, the curved surface portion 67 </ b> B of the engaging portion 67 provided in the developing unit 61 is in the operating portion 430 of the lock member 400. The upper surface 431 is pushed down to swing the lock member 400 backward. When the developing unit 61 is attached to the photoconductor unit 51, as shown in FIG. 9B, the lock member 400 swings forward by the action of a spring member (not shown), and the upper surface of the notch 421. The portion 422 and the flat portion 67A of the engaging portion 67 are engaged. As a result, the developing unit 61 is locked with respect to the photosensitive unit 51.

  As shown in FIG. 10, the developing unit 61 is configured such that the developing roller 63 is separated from the photosensitive drum 53 by a known mechanism. At this time, the top portion 130 of the protruding portion 100 of the developing unit 61 pushed upward is received in the second recess 222 provided in the biasing member 200. Thereby, compared with the configuration in which the top portion 130 directly contacts the biasing member 200 when the developing roller 63 is separated from the photosensitive drum 53, the force for separating the developing roller 63 can be reduced. As a result, it is not necessary to make a mechanism for pushing the developing unit 61 upward, so that the color printer 1 in which the process cartridge 50 is used can be downsized.

[Operation when developing unit is incorrectly installed]
Next, when the developing unit 61 is mounted on the photosensitive unit 51 at a position where the developing roller 63 is not correct with respect to the photosensitive drum 53, that is, the developing unit 61 is erroneously mounted on the photosensitive unit 51. The operation when this is done will be described. FIG. 11 is a diagram illustrating a state where the developing unit is mounted on the photosensitive unit at a position where the developing roller is not correct with respect to the photosensitive drum.

  In the present embodiment, since the extending portion 313 provided on the side wall 310 of the photoreceptor unit 51 has the bent portion 314 on the upper surface, the roller shaft 63A of the developing roller 63 is not inserted into the positioning groove 311. Even when it has been placed above the extended portion 313, it may be supported in a state of being caught by the bent portion 314 (the inclined surface 315). At this time, the developing roller 63 is in an incorrect position with respect to the photosensitive drum 53. As described above, when the developing unit 61 is mounted so that the roller shaft 63A is guided to the opening end 312 of the positioning groove 311, this does not occur.

  As shown in FIG. 11, even if the position of the developing roller 63 is different, the roller shaft 63 </ b> A is supported by the photosensitive unit 51, so the user can place the developing roller 63 in the correct position with respect to the photosensitive drum 53. There is a possibility that the developing unit 61 is mounted as it is. At this time, since the position of the developing roller 63 with respect to the photosensitive drum 53 is higher than the case where the developing roller 63 is correctly mounted, the user starts the mounting operation and moves the developing unit 61 in the counterclockwise direction shown in the drawing centering on the roller shaft 63A. When moved (turned) to the top, the top portion 130 approaches the urging member 200 obliquely from the upper rear side as compared with the case where the top portion 130 is correctly attached. Then, before the pressing surface 120 of the protruding portion 100 and the sliding contact portion 231 of the urging member 200 come into contact with each other, the protruding portion 100 (the protruding portion constituting the top portion 130) and the hooking portion 223 come into contact with each other.

  As a result, the projecting portion 100 is caught by the biasing member 200, so that the developing unit 61 cannot be accommodated in the accommodating portion 340 of the photosensitive unit 51, and the developing unit 61 can be attached to the photosensitive unit 51. Can not. As described above, according to the process cartridge 50 of the present embodiment, when the developing unit 63 is mounted on the photoconductor unit 51 at the position where the developing roller 63 is not correct with respect to the photoconductor drum 53, the protruding portion 100. Is caught by the urging member 200, it is possible to prevent erroneous mounting of the developing unit 61.

  Further, according to the present invention, in particular, the developing roller is supported separately from the photosensitive unit 51 having a shape in which the upper surface of the extending portion 313 provided on the side wall 310 is bent, that is, the positioning groove. It is possible to effectively prevent the developing unit from being erroneously attached to the photosensitive unit having a shape that can be formed.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment. About a concrete structure, it can change suitably in the range which does not deviate from the meaning of this invention.

  In the embodiment, the example in which the urging member 200 that urges the developing roller 63 toward the photosensitive drum 53 is employed as an example of the swinging member is shown, but the present invention is not limited to this. . For example, the lock member 400 described above may be employed as the swing member, or a swing member may be provided separately from the urging member 200 and the lock member 400. Note that by using the urging member 200 and the lock member 400 as the swinging member, the swinging member provided on the rear wall 330 of the photoconductor unit 51 can be reduced, so the configuration of the photoconductor unit 51 is simplified. And cost can be reduced.

  In the said embodiment, although the planar hooking part 223 was illustrated as a part which the protrusion part 100 of the urging | biasing member 200 (oscillating member) hooks, this invention is not limited to this. That is, when the developing unit is erroneously mounted, the shape is not particularly limited as long as the protruding portion is caught and the swinging member is not swung. For example, the upper end corner of the inclined sliding contact portion 231 may be used. May be.

  In the embodiment, the configuration in which the urging member 200 is provided with the first concave portion 221 and the second concave portion 222 is shown, but the first concave portion 221 and the second concave portion 222 are not indispensable configurations for the present invention. Therefore, for example, a configuration in which only one is provided or a configuration in which both are not provided as shown in FIG.

  12 mainly includes a shaft engaging portion 510, an arm portion 520, and a convex portion 530 having a triangular shape in a side view, and the front surface of the convex portion 530 is in contact with the sliding contact portion 531. The tip (upper end) of the arm part 520 is a hooking part 523. In such a configuration, the biasing member 500 is swung by the top portion 130 of the projecting portion 100 provided in the developing unit 61 being in direct sliding contact with the sliding contact portion 531.

  In the above embodiment, the process cartridge 50 according to the present invention is used in the color printer 1, but the present invention is not limited to this. For example, it may be used in a copying machine, a multifunction machine, a monochrome printer, or the like.

  In the embodiment, the image forming apparatus (color printer 1) using the process cartridge 50 exposes the photosensitive drum 53 (photosensitive body) by the LED unit 40 (LED light). It is not limited to this. For example, an image forming apparatus that exposes a photosensitive member with light emitted from an EL (electroluminescence) element or a phosphor or laser light may be used.

1 is a cross-sectional view illustrating an overall configuration of a color printer as an example of an image forming apparatus including a process cartridge according to the present invention. It is sectional drawing of the process cartridge which concerns on embodiment of this invention. FIG. 4 is a partial cross-sectional view for explaining a configuration of a photoconductor unit and a developing unit. (A) is a perspective view of the developing unit as seen from the back, and (b) is an enlarged view of the protruding portion. It is a perspective view which shows the structure of an extension part. It is a perspective view of a biasing member. It is a perspective view of a locking member. It is a figure for demonstrating operation | movement of the biasing member when mounting | wearing a developing unit correctly with respect to a photoreceptor unit, the figure (a) which shows a mode before a biasing member rock | fluctuates, It is a figure (b) which shows a mode that it rocks | fluctuates back. It is a figure for demonstrating operation | movement of a lock member when mounting | wearing a developing unit correctly with respect to a photoreceptor unit, (a) which shows a mode that a lock member rock | fluctuates by an engaging part, It is a figure (b) which shows a mode that the lock member engaged. It is a figure which shows the positional relationship of a rocking | swiveling member and protrusion part when a developing roller leaves | separates from the photoconductive drum. FIG. 10 is a diagram illustrating a state where the developing unit is mounted on the photosensitive unit at a position where the developing roller is not correct with respect to the photosensitive drum. It is a perspective view of the energizing member concerning a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 50 Process cartridge 51 Photoconductor unit 52 Photoconductor case 53 Photoconductor drum 61 Developing unit 63 Developing roller 100 Protruding part 110 Contact surface 120 Pressing surface 130 Top part 200 Energizing member 210 Shaft engaging part 221 1st recessed part 222 2nd recessed part 223 Hooking portion 231 Sliding portion 310 Side wall 311 Positioning groove 312 Open end 313 Extension portion 314 Bending portion 331 Shaft portion

Claims (5)

A photoconductor unit having a photoconductor on which an electrostatic latent image is formed; a developing unit having a developer carrier for supplying a developer to the photoconductor, and detachably attached to the photoconductor unit; A process cartridge comprising:
The photosensitive member unit is provided with a swinging member that swings in a direction approaching or separating from the developing unit on a side opposite to the side where the photosensitive member is disposed across the developing unit.
The developing unit protrudes toward the swinging member, and slides against the swinging member when the mounting unit is correctly attached to the photosensitive unit, thereby moving the swinging member away from the developing unit. Protruding part to swing is provided,
The protrusion is caught by the swinging member when the developing unit is mounted on the photoconductor unit at a position where the developer carrying body is not correct with respect to the photoconductor. Process cartridge. The protrusion is provided with a pressing surface that is recessed from the top,
The swinging member includes a sliding contact portion that is in sliding contact with the pressing surface when the developing unit is correctly mounted, and a sliding contact portion that avoids the top of the protruding portion when the developing unit is correctly mounted. The process cartridge according to claim 1, further comprising a first recessed portion that is also recessed.   2. The member according to claim 1, wherein the swinging member is a member that urges the developer carrying member toward the photosensitive member by being urged toward a direction close to the developing unit. The process cartridge according to claim 2.   The swing member is provided with a second recess for receiving the top of the protrusion of the developing unit attached to the photosensitive unit on the swing center side. 4. The process cartridge according to any one of 3 above. A positioning groove for positioning the developer carrier and an extending portion extending toward the opening end of the positioning groove so as to be along the positioning groove adjacent to the positioning groove are formed on the side wall of the photosensitive unit. Provided,
2. The extension portion is formed such that a surface opposite to the positioning groove is bent so as to extend from the distal end side along the positioning groove and then away from the positioning groove. The process cartridge according to claim 4.

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