Cartridge, and image forming apparatus

Abstract

To further develop a conventional configuration.SOLUTION: A cartridge comprises: a first unit that has a photoreceptor; a second unit that has a developing member, and is swingable relative to the first unit between a contact position and a separation position; a rotating member 170 that is rotatable to a first position for holding the second unit at the separation position against urging force for urging the second unit at the separation position toward the contact position, a second position for holding the second unit at the contact position, the second position to which the rotating member rotates in a first rotation direction R1 from the first position, and a third position to which the rotating member further moves in the first rotation direction R1 from the second position; and a pressing member 171 that can press the rotating member 170 in the first rotation direction R1, and is formed with a first surface 171d in contact with the rotating member 170 at the first position, and a second surface 171e recessed in a direction opposite to a direction in which the first surface 171d faces relative to the first surface 171d and can be in contact with the rotating member 170 when the rotating member 170 is at the third position.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a cartridge and an image forming apparatus equipped with the cartridge. [Background technology]

[0002] There is known an image forming apparatus in which a developing process is performed with a developing member in contact with a photosensitive drum. In such an image forming apparatus, the photosensitive drum and the developing member may be configured to be separable from each other. Patent Document 1 discloses a configuration including a holding member for holding the photosensitive drum and the developing member in a state of contact with each other or in a state of separation, and a contact force receiving member for receiving force from the apparatus main body and moving the holding member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-154312 Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention aims to further develop the conventional configuration. [Means for solving the problem]

[0005] In order to achieve the above object, the cartridge of the present invention comprises: A cartridge configured to be detachably attached to an image forming apparatus, a first unit having a photosensitive member; a second unit having a developing member for developing an electrostatic latent image formed on the photosensitive member, the second unit being configured to be swingable relative to the first unit between a contact position where the developing member contacts the photosensitive member and a separation position where the developing member is separated from the photosensitive member; a rotating member configured to be rotatable to a first position for holding the second unit at the separated position against a biasing force that biases the second unit at the separated position toward the abutting position, a second position for holding the second unit at the abutting position, the second position being rotated from the first position in a first rotation direction, and a third position further rotated from the second position in the first rotation direction; a pressing member configured to be able to press the rotating member in the first rotation direction, the pressing member having a first surface that contacts the rotating member when the rotating member is at the first position, and a second surface that is recessed with respect to the first surface in a direction opposite to the direction in which the first surface faces, the second surface being able to contact the rotating member when the rotating member is at the third position; The present invention is characterized by comprising: [Effects of the Invention]

[0006] According to the present invention, the conventional configuration can be further improved. [Brief explanation of the drawings]

[0007] [Figure 1] 10A and 10B are explanatory diagrams illustrating a configuration for switching the engagement position between the holding member and the force receiving member. [Figure 2] FIG. 1 is a schematic cross-sectional view of an image forming apparatus. [Figure 3] FIG. 2 is a cross-sectional view of the process cartridge. [Figure 4] FIG. 2 is a cross-sectional view of the image forming apparatus with the front door open. [Figure 5] FIG. 2 is a cross-sectional view of the image forming apparatus in a state where the tray is positioned outside the apparatus main body. [Figure 6] FIG. 2 is a cross-sectional view of the image forming apparatus with the process cartridge removed. [Figure 7] FIG. 2 is an exploded perspective view of the drum unit. [Figure 8] FIG. [Figure 9] FIG. 2 is an assembled perspective view of the process cartridge. [Figure 10]FIG. 2 is a perspective view of the process cartridge. [Figure 11] FIG. 2 is a perspective view showing the configuration of a development contact / separation mechanism. [Figure 12] 5A and 5B are explanatory diagrams of the contact and separation operation between the photosensitive drum and the developing roller. [Figure 13] FIG. [Figure 14] FIG. 10 is an explanatory diagram of a development contact suppression configuration. [Figure 15] 10A and 10B are explanatory diagrams illustrating the positional relationship between the protrusions and the force receiving member. [Figure 16] FIG. 10 is an explanatory diagram of the arrangement position of the protrusions. DETAILED DESCRIPTION OF THE INVENTION

[0008] The following describes in detail exemplary embodiments of the present invention with reference to the drawings. The dimensions, materials, shapes, and relative positions of the components described in the embodiments may be changed as appropriate depending on the configuration and various conditions of the device to which the invention is applied. In other words, the scope of the present invention is not limited to the following embodiments.

[0009] First, an image forming apparatus according to the present invention will be described. Here, the image forming apparatus is an apparatus that forms an image on a recording medium using various known image formation principles and methods, such as an electrophotographic process, an electrostatic recording process, or a magnetic recording process. Examples of such an apparatus include copiers, printers (e.g., laser printers, LED printers, etc.), facsimile machines, word processors, and image display devices (electronic blackboards and electronic whiteboards). The recording medium is the medium on which an image is formed by the image forming apparatus, and includes, for example, paper, overhead projectors, and image display bodies.

[0010] [Example 1] <General configuration of image forming apparatus> An electrophotographic image forming apparatus 1 (hereinafter referred to as image forming apparatus 1) according to Example 1 will be described with reference to Fig. 2. Fig. 2 is a schematic cross-sectional view showing the overall configuration of the image forming apparatus 1. The image forming apparatus 1 is an electrophotographic color laser beam printer that forms an image on a sheet-like recording medium S.

[0011] The image forming apparatus 1 is a four-color full-color laser beam printer that uses an electrophotographic process and forms a color image on a recording medium 3. The image forming apparatus 1 is of a process cartridge type that is configured so that the cartridge is detachably attached. A process cartridge 100 is detachably attached to the device main body 2 of the image forming apparatus 1, and the image forming apparatus 1 forms a color image on the recording medium 3. Figure 3 is a cross-sectional view of the process cartridge 100. The device main body 2 is formed with an opening for inserting and removing the process cartridge 100 into and from the device main body 2. The device main body 2 also has a front door 10 as an opening / closing member that opens and closes the opening.

[0012] In the following description, with respect to the image forming apparatus 1, the front side (front face side) refers to the side where the front door 10 is located. The rear side (rear face side) refers to the side opposite the front side (front face side). The front-rear direction refers to the direction from the rear side of the image forming apparatus 1 toward the front side (front direction) and the opposite direction (rear direction). The left and right refer to the left and right sides when the image forming apparatus 1 is viewed from the front side. The left-right direction refers to the direction from right to left (left direction) and the opposite direction (right direction). The up and down refer to the up and down sides in the direction of gravity (vertical direction). The up direction refers to the direction from bottom to top, and the down direction refers to the direction from top to bottom. FIG. 2 is a view of the image forming apparatus 1 viewed from the right side, with the up direction indicated as the Z1 direction, the down direction indicated as the Z2 direction, the rear direction indicated as the X1 direction, and the front direction indicated as the X2 direction. Also, FIG. 3 shows the process cartridge 100 installed in the apparatus main body 2.

[0013] When the image forming apparatus 1 is viewed from the front, the right side is the drive side of the image forming apparatus 1 (process cartridge 100), and the left side is the non-drive side. That is, Figure 2 is a cross-sectional view of the image forming apparatus 1 viewed from the non-drive side, with the front side of the page being the non-drive side of the image forming apparatus 1 and the back side being the drive side of the image forming apparatus 1. The drive side of the process cartridge 100 is the side on which a drum coupling member (photosensitive member coupling member) described later is arranged when viewed in the axial direction of the photosensitive drum, and is the side on which a developer coupling member described later is arranged when viewed in the axial direction of the developing roller (developing member).

[0014] First to fourth process cartridges 100 (100Y, 100M, 100C, 100K) are arranged in a substantially horizontal direction in the apparatus main body 2 of the image forming apparatus 1. Each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) has a similar electrophotographic process mechanism, but differs in the color and amount of developer (hereinafter referred to as toner). Therefore, in the following, unless a particular distinction is required, the suffixes Y to K will be omitted and the cartridges will be described collectively.

[0015] A rotational driving force is transmitted to the process cartridge 100 from a driving output unit (details of which will be described later) provided in the main body 2 of the apparatus, and a bias voltage (charge bias, developing bias, electrostatic residual detection bias, etc.) are supplied.

[0016] 3, the process cartridge 100 of the first embodiment has a drum unit 120 (first unit) that includes a photosensitive drum 101 and a charging means as a process means that acts on the photosensitive drum 101. Here, the drum unit 120 may have not only the charging means but also a cleaning means as a process means.

[0017] The process cartridge 100 also has a developing unit 150 (second unit) equipped with developing means for developing the electrostatic latent image on the photosensitive drum 101. The developing means includes, for example, a developing roller 103, which is a developing member that supplies toner to the photosensitive drum 101. The drum unit 120 and the developing unit 150 are coupled to each other. The photosensitive drum 101 and the developing roller 103 are configured to be able to come into contact with and separate from each other. When the process cartridge 100 is not installed in the apparatus main body 2 or when the development process is not being performed, the photosensitive drum 101 and the developing roller 103 are separated from each other, which makes it possible to suppress deformation of the elastic layer of the developing roller 103 and unnecessary adhesion of toner to the photosensitive drum 101. A more specific configuration of the process cartridge 100 will be described later.

[0018] The first process cartridge 100Y accommodates yellow (Y) toner in the developing frame and forms a yellow toner image on the surface of the photosensitive drum 101. The second process cartridge 100M accommodates magenta (M) toner in the developing frame and forms a magenta toner image on the surface of the photosensitive drum 101. The third process cartridge 100C accommodates cyan (C) toner in the developing frame and forms a cyan toner image on the surface of the photosensitive drum 101. The fourth process cartridge 100K accommodates black (K) toner in the developing frame and forms a black toner image on the surface of the photosensitive drum 101.

[0019] A laser scanner unit 11 serving as an exposure means is provided above the first to fourth process cartridges 100. The laser scanner unit 11 outputs a laser beam 12 corresponding to image information. The laser beam 12 passes through an exposure window 128 of the process cartridge 100 and scans and exposes the surface of the photosensitive drum 101.

[0020] An intermediate transfer unit 5 as a transfer member is provided below the first to fourth process cartridges 100. The intermediate transfer unit 5 includes a drive roller 5e, a tension roller 5f, and a The transfer belt 5a is flexible and is stretched over a drive roller 5e and a tension roller 5b.

[0021] The lower surface of the photosensitive drum 101 of each process cartridge 100 contacts the upper surface of the transfer belt 5a. A primary transfer roller 5d is provided inside the transfer belt 5a facing the photosensitive drum 101. The contact area between the photosensitive drum 101 and the transfer belt 5a is a primary transfer portion where a toner image is transferred from the photosensitive drum 101 to the transfer belt 5a. The primary transfer portion can also be said to be the portion where the photosensitive drum 101 and the transfer belt 5a contact each other via the transfer belt 5a.

[0022] A secondary transfer roller 6 is in contact with the drive roller 5e via the transfer belt 5a. The contact area between the transfer belt 5a and the secondary transfer roller 6 is a secondary transfer portion where a toner image is transferred from the transfer belt 5a to the recording medium 3. The secondary transfer portion can also be said to be the portion where the drive roller 5e and the secondary transfer roller 6 are in contact via the transfer belt 5a.

[0023] A feeding unit 4 is provided below the intermediate transfer unit 5. The feeding unit 4 has a paper feed tray 4a that stores a stack of recording media 3, and a paper feed roller 4b that transports the recording media 3 from the paper feed tray 4a.

[0024] A fixing device 7 and a paper discharge device 8 are provided on the front and upper side (upper right in FIG. 2) inside the device main body 2. A paper discharge tray 9 is also formed on the top surface of the device main body 2. After the toner image is fixed on the recording medium 3 by a fixing means provided in the fixing device 7, the recording medium 3 is discharged to the paper discharge tray 9.

[0025] <Image formation operation> Next, we will explain the image forming operation for forming a full-color image by the image forming apparatus 1. The control unit of the image forming apparatus 1 starts the image forming operation on the recording medium 3 based on an image signal received from an external host device. The external host device is, for example, a personal computer, an image reader, or a facsimile machine.

[0026] During image formation, the photosensitive drums 101 of the first to fourth process cartridges 100 are rotated at a predetermined speed in the direction of arrow A in Fig. 3. The transfer belt 5a is also rotated in the forward direction (the direction of arrow B in Fig. 2) relative to the rotation of the photosensitive drums 101 at a speed corresponding to the speed of the photosensitive drums 101.

[0027] The laser scanner unit 11 scans and exposes the surface of each photosensitive drum 101 with a laser beam 12 in accordance with an image signal for each color. Then, in synchronization with the driving of the laser scanner unit 11, the charging roller 102 in each process cartridge 100 uniformly charges the surface of the photosensitive drum 101 to a predetermined polarity and potential. As a result, an electrostatic latent image in accordance with the image signal for the corresponding color is formed on the surface of each photosensitive drum 101. The formed electrostatic latent image is developed by the developing roller 103, which is rotated at a predetermined speed in the forward direction (the direction of arrow C in FIG. 3 ) relative to the rotation of the photosensitive drum 101.

[0028] Through the above electrophotographic image forming process, a yellow toner image corresponding to the yellow component of the full-color image is formed on the photosensitive drum 101 of the first process cartridge 100Y. Then, the toner image is primarily transferred onto the transfer belt 5a.

[0029] Similarly, a magenta toner image corresponding to the magenta component of the full-color image is formed on the photosensitive drum 101 of the second process cartridge 100M. Then, the toner image is primarily transferred onto the transfer belt 5a, superimposed on the yellow toner image already transferred onto the transfer belt 5a. can be.

[0030] Similarly, a cyan toner image corresponding to the cyan component of the full-color image is formed on the photosensitive drum 101 of the third process cartridge 100C. Then, this toner image is primarily transferred onto the transfer belt 5a, superimposed on the yellow and magenta toner images already transferred onto the transfer belt 5a.

[0031] Similarly, a black toner image corresponding to the black component of the full-color image is formed on the photosensitive drum 101 of the fourth process cartridge 100K. Then, this toner image is primarily transferred onto the transfer belt 5a, superimposed on the yellow, magenta, and cyan toner images already transferred onto the transfer belt 5a.

[0032] In this way, an unfixed full-color toner image of four colors, yellow, magenta, cyan, and black, is formed on the transfer belt 5a.

[0033] Meanwhile, at a predetermined control timing, the recording media 3 are separated and fed one by one from the feeding unit 4. The recording media 3 are introduced at a predetermined control timing into the secondary transfer section, which is the contact point between the secondary transfer roller 6 and the transfer belt 5a. Then, as the recording media 3 is transported to the secondary transfer section, the four-color superimposed toner image on the transfer belt 5a is sequentially transferred onto the surface of the recording media 3 all at once.

[0034] <Process cartridge installation / removal configuration overview> The cartridge tray 20 (hereinafter referred to as the tray 20) that supports the process cartridge 100 will be described in further detail with reference to Figures 4 to 6. Figure 4 is a cross-sectional view of the image forming apparatus 1 in a state where the front door 10 is open and the tray 20 is located inside the apparatus main body 2. Figure 5 is a cross-sectional view of the image forming apparatus 1 in a state where the front door 10 is open and the tray 20 is located outside the apparatus main body 2, and the process cartridge 100 is housed inside the tray 20. Figure 6 is a cross-sectional view of the image forming apparatus 1 in a state where the front door 10 is open and the tray 20 is located outside the apparatus main body 2, and the first process cartridge 100Y has been removed from the tray 20.

[0035] As shown in FIGS. 4 and 5, the tray 20 is configured to be movable in the direction of arrow X1 (pushing direction) and the direction of arrow X2 (pulling direction), which are substantially horizontal, relative to the apparatus main body 2. That is, the tray 20 is configured to be capable of being pulled out and pushed into the apparatus main body 2, and is configured to be movable in a substantially horizontal direction when the image forming apparatus 1 is installed on a horizontal surface. Hereinafter, the position of the tray 20 located inside the apparatus main body 2 with the front door 10 open will be referred to as the "inside position," and the state of the tray 20 will be referred to as the "inside state." Furthermore, the position of the tray 20 located outside the apparatus main body 2 with the front door 10 open will be referred to as the "outside position," and the state of the tray 20 will be referred to as the "outside state." FIG. 4 shows the tray 20 in the inside position and in the inside state, and FIG. 5 shows the tray 20 in the outside position and in the outside state. When the tray 20 is in the inside state or the outside state, the photosensitive drum 101 and the transfer belt 5a are spaced apart from each other.

[0036] The tray 20 has a mounting portion 20a into which the first process cartridge 100Y is removably mounted. Similarly, the tray 20 has mounting portions 20a into which the second process cartridge 100M, the third process cartridge 100C, and the fourth process cartridge 100K are removably mounted. As shown in FIG. 6, the process cartridge 100 can be attached to and detached from the mounting portion 20a of the tray 20 in the outer position. When the process cartridge 100 is placed in the mounting portion 20a, it moves together with the tray 20 between the inside and outside of the apparatus main body 2.

[0037] In the first embodiment, when the front door 10 is closed, the intermediate transfer unit 5 is raised in the direction of the arrow Z1 by a link mechanism (not shown) and moves to a position for image formation (a position where the photosensitive drum 101 and the transfer belt 5a come into contact with each other). When the front door 10 is opened, the intermediate transfer unit 5 is lowered in the direction of the arrow Z2, and the photosensitive drum 101 and the transfer belt 5a are separated from each other.

[0038] As described above, the tray 20 allows a plurality of process cartridges 100 to be moved together to a position inside the apparatus main body 2 where image formation is possible, and can be pulled out to the outside of the apparatus main body 2 together.

[0039] <Overall structure of the process cartridge> Next, the configuration of the process cartridge 100 will be described in more detail with reference to Figures 7 to 10. Figure 7 is an exploded perspective view of the drum unit 120. Figure 8 is an exploded perspective view of the development unit 150. Figure 9 is an assembled perspective view of the process cartridge 100 as seen from the drive side, which is one end side in the axial direction of the photosensitive drum 101. Figure 10 is a perspective view of the process cartridge 100 as seen from the drive side.

[0040] The process cartridge 100 includes a photosensitive drum 101 and process means acting on the photosensitive drum 101. Here, the process means includes a charging roller 102 as charging means for charging the photosensitive drum 101, a developing roller 103 as developing means for developing the latent image formed on the photosensitive drum 101, etc. The process cartridge 100 is made up of a drum unit 120 as a first unit and a developing unit 150 as a second unit.

[0041] In the following description, the longitudinal direction Y of the drum unit 120 and the developing unit 150 is a direction substantially parallel to the rotation axis a of the photosensitive drum 101 shown in Fig. 9. Furthermore, when the process cartridge 100 is attached to the apparatus main body 2, the longitudinal direction Y is substantially parallel to the left-right direction of the image forming apparatus 1.

[0042] <Drum unit configuration> Next, we will explain the detailed configuration of the drum unit 120. As shown in Figures 7 and 9, the drum unit 120 is made up of a photosensitive drum 101, a charging roller 102, a drum frame 121, and the like.

[0043] The drum unit 120 includes a bearing unit 126 for the charge roller 102, which is disposed at the drive-side end of the charge roller 102, and a bearing unit 127 for the charge roller, which is disposed at the non-drive-side end. The bearing unit 126 has a bearing 126a that rotatably supports the charge roller 102, and a pressure spring 126b that urges the charge roller 102 toward the photosensitive drum 101. Similarly, the bearing unit 127 has a bearing 127a that rotatably supports the charge roller 102, and a pressure spring 127b that urges the charge roller 102 toward the photosensitive drum 101. Therefore, the charge roller 102 is rotatably supported by the bearings 126a and 127a, and is urged toward the photosensitive drum 101 by the pressure springs 126b and 127b in the direction of arrow F in FIG. 3.

[0044] Furthermore, a charge roller spacing member 129 is attached to the drive side end of the charge roller 102, and a charge roller spacing member 130 is attached to the non-drive side end. These members keep the charge roller 102 spaced apart from the photosensitive drum 101 in the initial shipping state. During use, the photosensitive drum 101 rotates, releasing the spaced state.

[0045] In addition, a cartridge cover is attached to the end of the process cartridge 100 on the driving side in the longitudinal direction. A member 122 is provided at the end on the non-drive side, and a cartridge cover member 123 is provided at the end on the non-drive side. The photosensitive drum 101 is rotatably supported by the cartridge cover members 122 and 123.

[0046] As shown in FIG. 9, a coupling member 125 for transmitting a driving force to the photosensitive drum 101 is provided at one end (drive side) in the longitudinal direction of the photosensitive drum 101. The coupling member 125 engages with a drum drive coupling 30 serving as a drum drive output unit provided in the apparatus main body 2. The driving force of a drive motor (not shown) of the apparatus main body 2 is transmitted to the photosensitive drum 101 via the drum drive coupling 30 and the coupling member 125, causing the photosensitive drum 101 to rotate in the direction of arrow A in FIG. 3. A drum flange 124 is provided at the other end (non-drive side) in the longitudinal direction of the photosensitive drum 101. Bearings 126a and 127a that support the charging roller 102 are supported by the drum frame 121 so that the charging roller 102 can contact the photosensitive drum 101 and rotate following the photosensitive drum 101 (in the direction of arrow E in FIG. 3).

[0047] <Configuration of the development unit> Next, the detailed configuration of the developing unit 150 will be described. As shown in Figures 3 and 8, the developing unit 150 is made up of a developing roller 103, a toner transport roller 104, a developing blade 156, a developing frame, etc. The developing frame includes a first developing frame 151 and a second developing frame 152. The first developing frame 151 and the second developing frame 152 are joined to each other by ultrasonic welding or the like.

[0048] The developing frame of the developing unit 150 is formed with a toner storage section 162 as a space for storing toner to be supplied to the developing roller 103. The developing frame also includes a bearing 153 provided on the drive side of the developing roller 103 and the toner transport roller 104, and a bearing 154 provided on the non-drive side. The developing frame rotatably supports the developing roller 103 and the toner transport roller 104 via the drive side bearing 153 and the non-drive side bearing 154, and holds a developing blade 156 that regulates the thickness of the toner layer on the circumferential surface of the developing roller 103.

[0049] The developing blade 156 is formed by attaching an elastic member 156b, which is a sheet metal with a thickness of about 0.1 mm, to a support member 156a, which is a metal material with an L-shaped cross section, by welding or the like. The developing blade 156 is attached to the developing frame at two locations, one end and the other end in the longitudinal direction, with fixing screws 156c.

[0050] A development drive input gear 159 for transmitting a driving force to the development unit 150 is provided on one end side (drive side) in the longitudinal direction of the development unit 150. The development drive input gear 159 is provided with a development input coupling portion 159a that receives driving force from a development drive coupling 40 provided in the apparatus main body 2. With this configuration, the driving force of a drive motor (not shown) of the apparatus main body 2 is input to the development unit 150.

[0051] The driving force input to the developing unit 150 is transmitted to the developing roller gear 157, causing the developing roller 103 to rotate in the direction of arrow C in Figure 3, and is transmitted to the toner transport roller gear 158, causing the toner transport roller 104 to rotate in the direction of arrow D in Figure 3.

[0052] The developing unit 150 also includes an agitating member 161 disposed inside the toner storage section 162, and an agitating gear 160 for driving the agitating member 161. When the driving force input to the developing unit 150 is transmitted to the agitating gear 160, the agitating member 161 is rotated in the direction of arrow G in FIG. 3, and the toner in the toner storage section 162 is agitated.

[0053] The agitating member 161 has a rotation axis 161a parallel to the rotation axis of the developing roller 103 and a conveying The toner storage unit 162 includes a first agitation sheet 161b and a second agitation sheet 161c as components. The first agitation sheet 161b and the second agitation sheet 161c are flexible sheets. One end of the first agitation sheet 161b and the second agitation sheet 161c is attached to the rotating shaft 161a, and the other end of the first agitation sheet 161b and the second agitation sheet 161c is free. As the rotating shaft 161a rotates, the first agitation sheet 161b and the second agitation sheet 161c also rotate, and the toner in the toner storage unit 162 is agitated by the first agitation sheet 161b and the second agitation sheet 161c.

[0054] Furthermore, at one end side (drive side) of the developing unit 150 in the longitudinal direction, a developing device cover member 155 that supports and covers a developing device drive input gear 159 is provided.

[0055] <Engagement structure of drum unit and developing unit> 9, the engagement structure (assembly structure) of the drum unit 120 and the developing unit 150 will be described. The drum unit 120 and the developing unit 150 are connected by a cartridge cover member 122 provided at the end of the process cartridge 100 on the driving side in the longitudinal direction, and a cartridge cover member 123 provided at the end of the process cartridge 100 on the non-driving side.

[0056] The cartridge cover member 122 on the drive side is provided with a developing unit support hole 122b for swingably (movably) supporting the developing unit 150, and a drum support hole 122a for rotatably supporting the photosensitive drum 101. Similarly, the cartridge cover member 123 on the non-drive side is provided with a developing unit support hole 123b for swingably supporting the developing unit 150, and a drum support hole 123a for rotatably supporting the photosensitive drum 101. In other words, the cartridge cover members 122 and 123 are support members that swingably support the developing unit 150 and rotatably support the photosensitive drum 101. That is, the cartridge cover members 122 and 123 support the developing unit 150 so that it can swing (move) between a developing position where the developing roller 103 abuts against the photosensitive drum 101 and a position where the developing roller 103 is separated from the photosensitive drum 101.

[0057] When the drum unit 120 and the developing unit 150 are engaged with each other, the outer diameter portion of the cylindrical portion 155a of the developing cover member 155 is fitted into the developing unit support hole 122b of the cartridge cover member 122 at one end (drive side). Also, the outer diameter portion of the cylindrical portion (not shown) of the bearing 154 is fitted into the developing unit support hole 123b of the cartridge cover member 123 at the other end (non-drive side).

[0058] Furthermore, one longitudinal end of the photosensitive drum 101 is fitted into a drum support hole 122a of the cartridge cover member 122, and the other end is fitted into a drum support hole 123a of the cartridge cover member 123. The cartridge cover members 122 and 123 are fixed to the drum unit 120 with screws, adhesive, or the like (not shown). As a result, the developing unit 150 is supported by the cartridge cover members 122 and 123 so as to be able to swing relative to the drum unit 120 (photosensitive drum 101), and the developing roller 103 can be positioned to act on the photosensitive drum 101 during image formation.

[0059] Through the above steps, the drum unit 120 and the developing unit 150 are assembled and integrally formed as the process cartridge 100. The assembled state of the drum unit 120 and the developing unit 150 is shown in Figure 10. Figure 10 is a perspective view of the process cartridge 100.

[0060] Hereinafter, the axis connecting the center of the developing unit support hole 122b of the cartridge cover member 122 on the driving side and the center of the developing unit support hole 123b of the cartridge cover member 123 on the non-moving side will be referred to as the swing axis b. The cylindrical portion 155a of the attached developing unit covering member 155 is coaxial with the developing input coupling portion 159a. That is, the developing unit 150 is configured so that a driving force is transmitted from the apparatus main body 2 to the swing shaft b. The developing unit 150 is also supported so as to be swingable about the swing shaft b.

[0061] The developing unit 150 is configured to be able to swing (move) between a contact position where the developing roller 103 contacts the photosensitive drum 101 and a separation position where the developing roller 103 is separated from the photosensitive drum 101. The apparatus main body 2 is also provided with a biasing mechanism that biases the developing unit 150 in a direction from the separation position toward the contact position. The biasing mechanism includes, for example, a tension spring (not shown) that biases the developing unit 150 and a development drive input gear 159 that applies rotational torque to the developing unit 150.

[0062] <Configuration of the contact / separation mechanism> Next, the contact / separation mechanism that brings the photosensitive drum 101 of the process cartridge 100 and the developing roller 103 of the developing unit 150 into contact with and separates them will be described. The contact / separation mechanism that is assembled to the non-drive side bearing 154 that constitutes the developing frame is shown in Figures 11(a) and 11(b). Figures 11(a) and 11(b) are perspective views showing the configuration of the contact / separation mechanism. Figure 11(a) shows the contact / separation mechanism in a state before assembly, and Figure 11(b) shows the state after assembly is complete. The contact / separation mechanism is made up of a holding member 170, a force receiving member 171, and a tension spring 172.

[0063] The holding member 170 has a supported portion 170a which is a hole having a substantially circular cross section. The supported portion 170a engages with a first support portion 154b provided on the bearing 154 on the non-drive side. The first support portion 154b is a protrusion that protrudes in the longitudinal direction of the developing unit 150. The holding member 170 is a rotating member (first rotating member) that is rotatably supported on the bearing 154 as a result of the supported portion 170a engaging with the first support portion 154b.

[0064] The holding member 170 also has a separation holding portion 170b that protrudes radially from the supported portion 170a. As shown in Figure 12(a), the separation holding portion 170b comes into contact with the abutment portion 123c of the non-driven side cartridge cover member 123, so that the holding member 170 maintains the development separation state of the process cartridge 100.

[0065] The force receiving member 171 has a supported portion 171a which is a slit having an oval cross section. The supported portion 171a engages with a second support portion 154c provided on the bearing 154. The second support portion 154c is a protrusion that protrudes in the longitudinal direction of the developing unit 150. The force receiving member 171 is a rotating member (second rotating member) that is supported on the bearing 154 so as to be movable parallel to the bearing 154 and rotatable, as a result of the supported portion 171a engaging with the second support portion 154c. In an orientation in which the process cartridge 100 is mounted in the apparatus main body 2, the supported portion 171a extends in the vertical direction, and the force receiving member 171 can move up and down while maintaining its orientation. Furthermore, when the force receiving member 171 is located in the lower portion of its movable range, i.e., when the second support portion 154c is located at the upper end of the supported portion 171a, the force receiving member 171 is configured to be rotatable.

[0066] Furthermore, the force receiving member 171 has a force receiving portion 171b that receives a force from a contact / separation control portion provided in the device main body 2. The force receiving member 171 rotates upon receiving force from the contact / separation control portion, thereby pressing the holding member 170 to rotate. In other words, the force receiving member 171 can also be said to be a pressing member configured to be able to press the holding member 170.

[0067] As shown in FIG. 11(b), when the process cartridge 100 is attached to the apparatus main body 2, the rotation center H (rotation axis) of the force receiving member 171 is located above the rotation center K (rotation axis) of the holding member 170. Also, the contact portion between the force receiving member 171 and the holding member 170 is located below the rotation center K and above the force receiving portion 171b. The distance from the contact portion to the rotation center H is greater than the distance from the contact portion to the rotation center K. In addition, the distance from the force receiving portion 171b to the rotation center H is greater than the distance from the contact portion to the rotation center H. With this configuration, the force applied to the force receiving member 171 to rotate the holding member 170 can be reduced.

[0068] Tension spring 172 is an urging member having one end fixed to holding member 170 and the other end fixed to force receiving member 171. Tension spring 172 applies an urging force in a direction that rotates force receiving member 171 relative to holding member 170.

[0069] <Contact / separation operation> The contact / separation operation between the photosensitive drum 101 and the developing roller 103 by the contact / separation mechanism will be described in detail with reference to Figures 12(a) to 12(d). Figures 12(a) to 12(d) are explanatory diagrams of the contact / separation operation between the photosensitive drum 101 and the developing roller 103. Figures 12(a) to 12(d) are partial cross-sectional views of the process cartridge 100 showing the contact state between the contacted portion 123c of the non-drive side cartridge cover member 123 and the separation maintaining portion 170b. Figures 12(a) to 12(d) show the process cartridge 100 in the posture in which it is installed in the image forming apparatus 1.

[0070] 12(a) shows a state in which the process cartridge 100 is mounted in the apparatus main body 2 of the image forming apparatus 1 with the front door 10 open. In this state, the separation holding portion 170b of the holding member 170 abuts against the abutted portion 123c of the cartridge cover member 123. The process cartridge 100 is in a development separation state in which the photosensitive drum 101 and the developing roller 103 are separated from each other. The abutment of the holding member 170 against the cartridge cover member 123 restricts the developing roller 103 from approaching the photosensitive drum 101, and the developing unit 150 (developing roller 103) is held in the separation position.

[0071] FIG. 12(b) shows a state in which the front door 10 of the image forming apparatus 1 has been closed from the state shown in FIG. 12(a). When the front door 10 is closed, the force receiving member 171 is pressed from above by a link mechanism that operates in conjunction with the closing operation of the front door 10, and moves downward. The force receiving member 171 is urged upward by a biasing member (not shown), and the link mechanism moves the force receiving member 171 downward against the biasing force of the biasing member. At this time, the force receiving member 171 moves so that the force receiving portion 171b, which is the lower end of the force receiving member 171, protrudes downward from the non-driven side bearing 154. In this state, the separation holding portion 170b of the holding member 170 abuts against the abutment portion 123c of the cartridge cover member 123. The process cartridge 100 is in a development separation state in which the photosensitive drum 101 and the developing roller 103 are spaced apart from each other.

[0072] 12(b), the holding member 170 abuts against the cartridge cover member 123, thereby restricting the movement of the developing unit 150, which is biased by the biasing structure, from the separated position to the abutting position. The position of the holding member 170 shown in FIG. 12(b), which is for holding the developing unit 150 so that the process cartridge 100 is in the development separated state, is referred to as the first position.

[0073] 12(c) shows how the force receiving portion 171b of the force receiving member 171 starts to move as it is pressed in the first direction W1 by a separation control unit provided in the apparatus main body 2. The first direction W1 is a direction in which the force receiving portion 171b approaches the cartridge cover member 123 and is a direction that intersects with the rotation axes of the photosensitive drum 101 and the developing roller 103. When the force receiving portion 171b starts to be pressed, the separation holding portion 170b of the holding member 170 abuts against the abutted portion 123c of the cartridge cover member 123.

[0074] When the force receiving portion 171b receives a force in the first direction W1, the force receiving member 171 rotates. When the force receiving portion 171b rotates, the holding member 170 is pressed by the force receiving member 171 and rotates. Hereinafter, the direction in which the holding member 170 rotates when the force receiving portion 171b receives a force in the first direction W1 and moves will be referred to as a first rotation direction R1. Furthermore, the direction in which the force receiving member 171 rotates when the force receiving portion 171b receives a force in the first direction W1 will be referred to as a second rotation direction R2.

[0075] 12(d) shows a state in which the force receiving member 171 has further rotated in the second rotation direction R2 from the state in FIG. 12(c), and the holding member 170 has further rotated in the first rotation direction R1. When the holding member 170 rotates in the first rotation direction R1, the separation holding portion 170b of the holding member 170 moves upward. Then, the separation holding portion 170b moves away from the abutment portion 123c of the cartridge cover member 123.

[0076] When the holding member 170 separates from the cartridge cover member 123, the developing unit 150 is swung from the separated position to the abutting position so that the developing roller 103 approaches and abuts against the photosensitive drum 101. That is, the abutment state between the separation holding portion 170b and the abutted portion 123c is released, so that the photosensitive drum 101 and the developing roller 103 abut against each other, and the process cartridge 100 is in a developing abutment state. In other words, when the holding member 170 moves to a position separated from the cartridge cover member 123, the developing unit 150 is held in the abutment position. The position shown in FIG. 12(d), which is for holding the developing unit 150 so that the process cartridge 100 is in a developing abutment state, is referred to as the second position.

[0077] As described above, the holding member 170 is configured to be rotatable between a first position and a second position. The holding member 170 is also configured to be rotatable from the second position in the first rotation direction R1 to a third position. Details of the third position will be described later. In the following description, the position of the force receiving member 171 shown in FIG. 12(b) will be referred to as the fourth position, and the position of the force receiving member 171 shown in FIG. 12(a) will be referred to as the fifth position. That is, the force receiving member 171 is configured to be translatable between the fourth position, where it is rotatable in the second rotation direction R2, and the fifth position, which is higher than the fourth position.

[0078] By the above operation, the developing unit 150 moves from the separated position to the abutting position, and the process cartridge 100 transitions from the developer separated state to the developer abutting state. When the process cartridge 100 is in the developer abutting state, the image forming apparatus 1 is able to perform image formation operations.

[0079] Next, the force application member 111 of the contact / separation control unit that applies force to the force receiving member 171 will be described. FIGS. 13(a) to 13(d) are explanatory diagrams of the force application member 111. The force application member 111 has a force application portion 111a that applies force to the force receiving member 171, and is provided on the device body 2 so as to be movable in the first direction W1 and the second direction W2. The force application portion 111a includes a surface facing the first direction W1 and a surface facing the second direction W2, and has a U-shaped cross section perpendicular to the rotation axis of the holding member 170. When the force receiving member 171 is in the fourth position, the tip of the force receiving member 171 is located between the surface facing the first direction W1 and the surface facing the second direction W2 of the force application member 111.

[0080] Figure 13(a) shows a state in which the holding member 170, which is in the first position, abuts against the cartridge cover member 123, and the developing unit 150 is held at the separated position. At this time, a gap is provided between the force application member 111 and the force receiving member 171. When the force application member 111 moves in the first direction W1 from the state shown in Figure 13(a), the force application portion 111a presses the force receiving portion 171b, and the force receiving member 171 rotates in the second rotation direction R2. Figure 13(b) shows a state in which the force receiving member 171 is pressed by the force application member 111 and rotates in the second rotation direction R2, and the holding member 170 is pressed by the force receiving member 171 and moves to the second position.

[0081] FIG. 13(c) shows a state in which the force application member 111 has moved in the second direction W2 from the state in FIG. 13(b) and is separated from the force receiving member 171. The holding member 170 has moved to the second position and the car After the force application member 111 moves away from the cartridge cover member 123 and the developing roller 103 comes into contact with the photosensitive drum 101, the force application member 111 moves in the second direction W2 and moves away from the force receiving member 171. After the force application member 111 moves, a gap is formed between the force application member 111 and the force receiving member 171. Furthermore, when the force application member 111 moves in the second direction W2 and moves away from the force receiving member 171, the force receiving member 171 rotates slightly in the direction opposite to the second rotation direction R2 due to the biasing force of the biasing member that biases the force receiving member 171 upward, etc. Then, the holding member 170 also attempts to rotate in the direction opposite to the first rotation direction R1 due to the biasing force of the tension spring 172, etc., but as shown in FIG. 13C, the rotation of the holding member 170 is restricted by the cartridge cover member 123. With this configuration, even if the force application member 111 is separated from the force receiving member 171, the holding member 170 is prevented from unintentionally rotating from the second position to the first position. During an image formation operation by the image forming apparatus 1, the holding member 170, the force receiving member 171, and the force application member 111 are in the positions shown in Figure 13(c). At this time, the holding member 170 and the force receiving member 171 are separated from each other.

[0082] On the other hand, when the developing unit 150 moves from the contact position to the separated position and the process cartridge 100 transitions from the developer-contact state to the developer-separated state, the force applying member 111 moves in the second direction W2 to press the force receiving member 171. A force receiving portion 171g formed on the opposite side of the force receiving portion 171b of the force receiving member 171 is pressed in the second direction W2 by the force applying portion 111a, causing the force receiving member 171 to move in the direction opposite to the second rotation direction R2. As a result, the developing unit 150, together with the developing frame supporting the force receiving member 171, swings in a direction away from the drum unit 120, and the developing roller 103 separates from the photosensitive drum 101. Furthermore, as the force receiving member 171 moves, the biasing force of the tension spring 172 causes the holding member 170 to rotate from the second position to the first position in the direction opposite to the first rotation direction R1. Thereafter, when the force application member 111 moves in the first direction W1 and separates from the force receiving member 171, the developing unit 150 swings toward the drum unit 120 due to the biasing force of the biasing structure, and the separation maintaining portion 170b comes into contact with the contacted portion 123c. Then, when the front door 10 is opened and the force receiving member 171 is released from the state in which it was pressed by the link mechanism linked to the opening and closing operation of the front door 10, the force receiving member 171 moves upward from the fourth position toward the fifth position.

[0083] <Configuration for preventing contact of developing device when cartridge is individually installed> As described above, in the process cartridge 100, the developer contact state and the developer separation state are switched by the movement (rotation) of the force receiving member 171. Therefore, for example, when a user performs an operation of attaching or detaching the process cartridge 100, the force receiving member 171 may be unintentionally pressed or moved, and the process cartridge 100 may erroneously switch from the developer separation state to the developer contact state. Therefore, the process cartridge 100 is provided with a function to switch the developer contact state when the process cartridge 100 is not attached to the image forming apparatus 1 (individually mounted state). The developer contact suppression function prevents the user from unintentionally releasing the developer separation state in the developer contact state. The developer contact suppression structure will be described with reference to Figures 14(a) and 14(b). Figures 14(a) and 14(b) are explanatory diagrams of the developer contact suppression structure.

[0084] The developing unit 150 has a protrusion 154a as a regulating portion that regulates rotation of the force receiving member 171 in the second rotation direction R2 so as to move the holding member 170 from the first position to the second position. In Example 1, the protrusion 154a is provided on the bearing 154 on the non-drive side, and protrudes toward the force receiving member 171 in the direction of the rotation axis of the developing roller 103. In other words, the bearing 154 has the protrusion 154a, and can also be said to be a regulating member that regulates rotation of the force receiving member 171. In addition, the force receiving member 171 is provided with a regulated portion 171c that engages with the protrusion 154a.

[0085] FIG. 14(a) shows the process cartridge 100 when it is not mounted in the apparatus main body 2. At this time, the force receiving member 171 is in the fifth position. When the force receiving member 171 is in the fifth position, When the force receiving member 171 is in the fifth position, the regulated portion 171c is located downstream of the protrusion 154a in the second rotation direction R2 (first direction W1) and is located so as to overlap with the protrusion 154a when viewed in the first direction W1. In other words, since the protrusion 154a is located on the rotation trajectory of the regulated portion 171c, when the force receiving member 171 attempts to move in the second rotation direction R2, the regulated portion 171c abuts against the protrusion 154a, and the protrusion 154a regulates the rotation of the force receiving member 171 in the second rotation direction R2. In this way, when the force receiving member 171 is in the fifth position, the rotation in the second rotation direction R2 is regulated by the protrusion 154a.

[0086] FIG. 14B shows the process cartridge 100 when it is attached to the apparatus main body 2 and the front door 10 is closed. At this time, the force receiving member 171 is pressed from above and moves from the fifth position to the fourth position, which is lower than the fifth position. When the force receiving member 171 is in the fourth position, the regulated portion 171c is positioned below the protrusion 154a and does not overlap with the protrusion 154a when viewed in the first direction W1. In other words, since the protrusion 154a is positioned outside the rotation locus of the regulated portion 171c, even if the force receiving member 171 moves in the second rotation direction R2, the regulated portion 171c does not come into contact with the protrusion 154a, and the protrusion 154a does not restrict the rotation of the force receiving member 171 in the second rotation direction R2. As described above, the force receiving member 171 moves from the fifth position to the fourth position in conjunction with the closing of the front door 10.

[0087] 15 is an explanatory diagram of the positional relationship between the protrusion 154a and the force receiving member 171. When the force receiving member 171 is located in the fourth position and the holding member 170 is located in the first position, the first engagement surface 171d of the force receiving member 171 abuts against the pressed surface 170c of the holding member 170. The first engagement surface 171d is a surface facing downstream in the second rotation direction R2, and the pressed surface 170c is a surface facing upstream in the first rotation direction R1. As shown in FIG. 15, the protrusion 154a is located upstream in the second rotation direction R2 of the first engagement surface 171d and the pressed surface 170c, i.e., the contact portion between the force receiving member 171 and the holding member 170. Due to this arrangement, when the process cartridge 100 is attached to the image forming apparatus 1, the rotation of the holding member 170 in the first rotation direction R1 and the rotation of the force receiving member 171 in the second rotation direction R2 are not hindered by the protrusion 154a.

[0088] As described above, the force receiving member 171 is configured to be movable in parallel between the fourth position and the fifth position and to be rotatable at the fourth position. When the force receiving member 171 is at the fourth position, it rotates in the second rotation direction R2, thereby pressing the holding member 170 in the first rotation direction R1. When the force receiving member 171 is at the fifth position, the regulated portion 171c abuts against the protrusion 154a when the force receiving member 171 rotates in the second rotation direction R2. With this configuration, when the process cartridge 100 is removed from the main body 2 of the apparatus, the force receiving member 171 is at the fifth position, so that the developer separation state of the process cartridge 100 is maintained. On the other hand, when the process cartridge 100 is attached to the main body 2 of the apparatus and the force receiving member 171 moves from the fifth position to the fourth position, the force receiving member 171 becomes rotatable. When the force receiving member 171 rotates, the holding member 170 is rotated, and the contact and separation operation between the photosensitive drum 101 and the developing roller 103 in the process cartridge 100 is performed.

[0089] 16 is an explanatory diagram of the arrangement position of the protrusion 154a. When the force receiving member 171 is in the fifth position, the protrusion 154a is provided at a position closer to the force receiving portion 171b than the rotation center K of the holding member 170 in the direction connecting the rotation center H of the force receiving member 171 and the force receiving portion 171b. In other words, when the force receiving member 171 is in the fifth position, as viewed in the longitudinal direction of the developing unit 150, the distance D1 from the protrusion 154a to the force receiving portion 171b is smaller than the distance D2 from the rotation center K of the holding member 170 to the force receiving portion 171b. If the distance from the force receiving portion 171b to the protrusion 154a or the regulated portion 171c is large, the force receiving portion 171b will not receive force from the force applying member 111 when the regulated portion 171c is in contact with the protrusion 154a. When the force is received, the amount of deformation of the force receiving member 171 increases. On the other hand, by making the distance from the protrusion 154a (regulated portion 171c) to the force receiving portion 171b small, it is possible to suppress deformation of the force receiving member 171 when the force receiving portion 171b receives a force, compared to when this distance is large. Therefore, it is possible to reduce the amount of rotation (distance) of the holding member 170 in the first rotation direction R1 due to deformation of the force receiving member 171, and therefore it is possible to more reliably suppress release of the developer separation state of the process cartridge 100.

[0090] With the above-described configuration, in the first embodiment, the position of the force receiving member 171 differs between when the process cartridge 100 is individually packaged and when the process cartridge 100 is attached to the main body 2 of the apparatus. When the process cartridge 100 is individually packaged, rotation of the force receiving member 171 in the second rotation direction R2 is restricted, whereas when the process cartridge 100 is attached to the main body 2 of the apparatus, rotation of the force receiving member 171 in the second rotation direction R2 is not restricted. This configuration prevents the force receiving member 171 from accidentally moving when the process cartridge 100 is individually packaged, causing the process cartridge 100 to transition from the developer-separated state to the developer-contacted state. Furthermore, when the process cartridge 100 is attached to the main body 2 of the apparatus, the force receiving member 171 can be moved as intended to switch the process cartridge 100 between the developer-separated state and the developer-contacted state.

[0091] <Configuration for switching the engagement position of the holding member and the force receiving member> As described above, in the first embodiment, the holding member 170 moves from the first position to the second position, causing the developing unit 150 to swing from the separation position to the contact position. However, if the rotation range of the holding member 170 is designed to be from the first position to the second position, dimensional variations or deformation of components may prevent the holding member 170 from rotating to the second position as designed, resulting in a risk of the developing device contact-separation operation not being performed properly. On the other hand, if the rotation range of the holding member 170 is excessively widened, the movement range of the force application member 111 is widened, which may cause the force application member 111 to interfere with other components. Furthermore, if the movement range of the force application member 111 is widened, the force application member 111 needs to be positioned away from the drum unit 120, etc., which may result in an increase in the size of the image forming apparatus 1. Therefore, in the first embodiment, the holding member 170 and the force receiving member 171 are configured to more reliably perform the developing device contact-separation operation while suppressing an increase in the size of the image forming apparatus 1. The configurations of the holding member 170 and the force receiving member 171 for solving the above problems will be described below.

[0092] 1(a) and 1(b) will be used to explain the configuration for switching the engagement position EP between the holding member 170 and the force receiving member 171. Figures 1(a) and 1(b) are explanatory diagrams of the configuration for switching the engagement position EP between the holding member 170 and the force receiving member 171. The engagement position EP is the position where the holding member 170 and the force receiving member 171 are engaged, and is the point where the two members come into contact.

[0093] 1(b), the force receiving member 171 has, as surfaces that engage with the holding member 170, a first engagement surface 171d as a first surface, a second engagement surface 171e as a second surface, and an inclined surface 171f as a connecting surface. At least when the developing unit 150 is in the separated position, the first engagement surface 171d, the second engagement surface 171e, and the inclined surface 171f all face toward the first direction W1. More specifically, when the holding member 170 is in the first position, the first engagement surface 171d and the second engagement surface 171e are approximately perpendicular to the first direction W1.

[0094] The first engagement surface 171d is formed at the tip end portion of the force receiving member 171 (the end portion on the force receiving portion 171b side). The second engagement surface 171e is formed on the supported portion 171a side (the rotation center side of the force receiving member 171) of the first engagement surface 171d, and on the second direction W2 side of the first engagement surface 171d. In other words, the second engagement surface 171e is formed so as to be recessed in the direction opposite to the direction in which the first engagement surface 171d faces, with respect to the first engagement surface 171d. Furthermore, the second engagement surface 171e is approximately parallel to the first engagement surface 171d. The inclined surface 171f is formed on the first engagement surface 171d. This surface connects the mating surface 171d and the second engagement surface 171e, and is formed to be inclined with respect to the first engagement surface 171d and the second engagement surface 171e.

[0095] 1(a) shows the state in which the holding member 170 is in the middle of moving from the first position to the second position. When the holding member 170 is in the first position, the pressed surface 170c of the holding member 170 contacts the first engagement surface 171d of the force receiving member 171. At this time, the engagement position EP between the holding member 170 and the force receiving member 171 is on the first engagement surface 171d.

[0096] As the force receiving member 171 rotates in the second rotation direction R2, the holding member 170 rotates in the first rotation direction R1, and the pressed surface 170c gradually moves upward. When the holding member 170 reaches the second position, the pressed surface 170c comes into contact with the inclined surface 171f. At this time, the engagement position EP between the holding member 170 and the force receiving member 171 is on the inclined surface 171f. Note that when the holding member 170 is located in the second position, the engagement position EP may also be configured to be on the first engagement surface 171d or the second engagement surface 171e.

[0097] Furthermore, in the first embodiment, the holding member 170 is configured to be further rotatable from the second position in the first rotation direction R1. The third position is the position where the holding member 170 contacts the drum unit 120 (photosensitive unit) when it is pushed by the force receiving member 171 and moves further from the second position in the first rotation direction R1. That is, the holding member 170 is configured to be rotatable to the first position, the second position, and the third position. When the holding member 170 is in the third position, the developing roller 103 contacts the photosensitive drum 101, and the process cartridge 100 is in a developing contact state.

[0098] By configuring the holding member 170 to be rotatable in the first rotation direction R1 from the second position to the third position, the process cartridge 100 can be reliably switched from the developer-separated state to the developer-contact state even if there is variation in the dimensions of the parts or if the parts are deformed. In this way, the process cartridge 100 is configured to be able to more reliably switch from the developer-separated state to the developer-contact state, taking into account variation in the dimensions of the parts and deformation.

[0099] FIG. 1B shows a state in which the holding member 170 has moved to the third position. When the holding member 170, which is at the second position, further rotates in the first rotation direction R1, the pressed surface 170c moves from the inclined surface 171f onto the second engagement surface 171e. When the holding member 170 is at the third position, the pressed surface 170c of the holding member 170 comes into contact with the second engagement surface 171e of the force receiving member 171. At this time, the engagement position EP between the holding member 170 and the force receiving member 171 is on the second engagement surface 171e. When the holding member 170 is at the third position, the holding member 170 comes into contact with the cartridge cover member 123 of the drum unit 120. Therefore, the drum unit 120 prevents the holding member 170 from rotating excessively in the second rotation direction R2 beyond the third position.

[0100] As described above, in the first embodiment, as the holding member 170 moves from the first position to the second position, the engagement position EP moves upward on the first engagement surface 171d and reaches the inclined surface 171f. Then, as the holding member 170 moves from the second position to the third position, the engagement position EP moves from the inclined surface 171f to the second engagement surface 171e. Therefore, as the holding member 170 rotates from the first position to the third position, the contact target of the pressed surface 170c switches from the first engagement surface 171d to the second engagement surface 171e, which is recessed from the first engagement surface 171d.

[0101] The engagement position EP between the force receiving member 171 and the holding member 170 is switched from on the first engagement surface 171d to on the second engagement surface 171e, so that the movement amount (rotation amount) of the holding member 170 can be reduced relative to the movement amount of the force receiving member 171. To rotate the holding member 170 to the second position, it is necessary to move the force application member 111 in the first direction W1 and rotate the force receiving member 171 in the second rotation direction R2. However, with the above-described configuration, the rotation amount of the holding member 170 is reduced, so the distance that the force application member 111 moves in the first direction W1, i.e., in the direction toward the drum unit 120, can be reduced. Therefore, the force application member 111 can be disposed in a position closer to the drum unit 120, and the size of the image forming apparatus 1 can be reduced. In other words, even in a configuration in which the holding member 170 can rotate from the second position to the third position, it is possible to reduce the arrangement space (movement range) of the force application member 111 while preventing unintended contact between the holding member 170 and the drum unit 120. Furthermore, the reduction in the arrangement space for the force application member 111 allows the size of the image forming apparatus 1 to be reduced accordingly.

[0102] As described above, first engagement surface 171d and second engagement surface 171e are connected by inclined surface 171f. Inclined surface 171f is formed so that the angle formed with second engagement surface 171e is an obtuse angle. With this configuration, when holding member 170 returns from the third position to the first position, holding member 170 is guided by inclined surface 171f, and returns without getting caught from the position where it contacts second engagement surface 171e to the position where it contacts first engagement surface 171d.

[0103] In the above description, the contact / separation mechanism and the developing device contact suppression configuration on the non-driven side of the process cartridge 100 have been described, but similar mechanisms and configurations are also provided on the driven side.

[0104] The disclosure of this embodiment includes the following configuration. (Configuration 1) A cartridge configured to be detachably attached to an image forming apparatus, a first unit having a photosensitive member; a second unit having a developing member for developing an electrostatic latent image formed on the photosensitive member, the second unit being configured to be swingable relative to the first unit between a contact position where the developing member contacts the photosensitive member and a separation position where the developing member is separated from the photosensitive member; a rotating member configured to be rotatable to a first position for holding the second unit at the separated position against a biasing force that biases the second unit at the separated position toward the abutting position, a second position for holding the second unit at the abutting position, the second position being rotated from the first position in a first rotation direction, and a third position further rotated from the second position in the first rotation direction; a pressing member configured to be able to press the rotating member in the first rotation direction, the pressing member having a first surface that contacts the rotating member when the rotating member is at the first position, and a second surface that is recessed with respect to the first surface in a direction opposite to the direction in which the first surface faces, the second surface being able to contact the rotating member when the rotating member is at the third position; A cartridge comprising: (Configuration 2) The cartridge described in configuration 1 is characterized in that the pressing member is formed with a connection surface that connects the first surface and the second surface, and the angle that the connection surface forms with the second surface is an obtuse angle. (Configuration 3) The cartridge according to configuration 2, wherein the pressing member contacts the rotating member at the connecting surface when the rotating member is in the second position. (Configuration 4) 4. The cartridge according to any one of configurations 1 to 3, wherein the second surface is formed closer to the rotation center of the pressing member than the first surface. (Configuration 5) The second unit includes a developing frame that supports the developing member, the rotating member, and the pressing member. 5. The cartridge according to any one of configurations 1 to 4, having a body. (Configuration 6) the pressing member is configured to be rotatable in a second rotation direction around a rotation axis parallel to the rotation axis of the rotating member, The cartridge according to any one of configurations 1 to 5, wherein when the rotating member is in the first position, the distance from the contact portion between the rotating member and the pressing member to the rotation center of the pressing member is greater than the distance from the contact portion to the rotation center of the rotating member. (Configuration 7) the pressing member has a force receiving portion that receives a force for rotating in the second rotation direction, The cartridge according to configuration 6, wherein when the rotating member is in the first position, the distance from the force receiving portion to the rotation center of the pressing member is greater than the distance from the contact portion between the rotating member and the pressing member to the rotation center of the pressing member. (Configuration 8) A device body, a cartridge according to any one of configurations 1 to 7 that is detachably attached to the device main body; An image forming apparatus comprising: (Configuration 9) A device body, The cartridge according to configuration 7, which is detachable from the device main body; An image forming apparatus comprising: a force applying member that applies a force to the force receiving portion. [Explanation of symbols]

[0105] 1...image forming apparatus, 100...process cartridge (cartridge), 101...photosensitive drum (photosensitive member), 120...drum unit (first unit), 150...developing unit (second unit), 170...holding member (rotating member), 171...force receiving member (pressing member), 171d...first engagement surface (first surface), 171e...second engagement surface (second surface)

Claims

1. A cartridge configured to be detachably attached to an image forming apparatus, a first unit having a photosensitive member; a second unit having a developing member for developing an electrostatic latent image formed on the photosensitive member, the second unit being configured to be swingable relative to the first unit between a contact position where the developing member contacts the photosensitive member and a separation position where the developing member is separated from the photosensitive member; a rotating member configured to be rotatable to a first position for holding the second unit at the separated position against a biasing force that biases the second unit from the separated position toward the abutting position, a second position for holding the second unit at the abutting position, the second position being rotated from the first position in a first rotation direction, and a third position further rotated from the second position in the first rotation direction; a pressing member configured to be able to press the rotating member in the first rotation direction, the pressing member having a first surface that contacts the rotating member when the rotating member is at the first position, and a second surface that is recessed with respect to the first surface in a direction opposite to the direction in which the first surface faces, the second surface being able to contact the rotating member when the rotating member is at the third position; A cartridge comprising:

2. 2. The cartridge according to claim 1, wherein the pressing member is formed with a connection surface that connects the first surface and the second surface, the connection surface forming an obtuse angle with the second surface.

3. 3. A cartridge according to claim 2, wherein the pressing member contacts the rotating member at the connecting surface when the rotating member is in the second position.

4. 2. A cartridge according to claim 1, wherein the second surface is formed closer to the center of rotation of the pressing member than the first surface.

5. 2. A cartridge according to claim 1, wherein said second unit has a developing device frame supporting said developing member, said rotating member and said pressing member.

6. the pressing member is configured to be rotatable in a second rotation direction around a rotation axis parallel to the rotation axis of the rotating member, 2. A cartridge according to claim 1, wherein when the rotating member is in the first position, the distance from the contact point between the rotating member and the pressing member to the rotation center of the pressing member is greater than the distance from the contact point to the rotation center of the rotating member.

7. the pressing member has a force receiving portion that receives a force for rotating in the second rotation direction, 7. A cartridge according to claim 6, wherein when the rotating member is in the first position, the distance from the force receiving portion to the rotation center of the pressing member is greater than the distance from the contact portion between the rotating member and the pressing member to the rotation center of the pressing member.

8. A device body, a cartridge according to any one of claims 1 to 7 that is detachably attached to the main body of the device; An image forming apparatus comprising:

9. A device body, The cartridge according to claim 7, which is detachable from the main body of the apparatus; An image forming apparatus comprising: a force applying member that applies a force to the force receiving portion.

Images