JP2023091023A - cartridge unit - Google Patents

Abstract

To solve the problem in which: when a holding member that holds a developing unit at a separate position is moved due to vibration or mechanical shock at the time a process cartridge is conveyed, the photoreceptor and a developer carrier are brought into contact with each other.SOLUTION: A cartridge unit comprises a process cartridge and a cover member to which the process cartridge is removably mounted. The process cartridge includes: (i) a first unit provided with a photoreceptor; (ii) a second unit provided with a developer carrier and constructed to be movable to a contact position and a separate position; and (iii) a holding member which is constructed so as to be movable to a hold position where the second unit is held at the separate position and a release position where the second unit is permitted to move from the separate position to the contact position. The movement of the holding member from the hold position to the release position is restricted by the cover member.SELECTED DRAWING: Figure 1

Description

The present invention relates to a cartridge unit having a process cartridge used in an image forming apparatus employing an electrophotographic image forming method (hereinafter referred to as electrophotographic method) and a cover member detachably attached to the process cartridge.

Image forming apparatuses employing the electrophotographic method include electrophotographic copiers, electrophotographic printers (eg, laser beam printers, LED printers, etc.), facsimile machines, word processors, and the like.

Further, a process cartridge is an electrophotographic photosensitive member, which is an image carrier, and process means acting on the electrophotographic photosensitive member are integrated into a cartridge, and this cartridge is detachable from the main body of the image forming apparatus. It is.

2. Description of the Related Art In an image forming apparatus using an electrophotographic method, a contact development method may be adopted in which an image is formed while a developer carrier is in contact with a photosensitive member serving as an image carrier. On the other hand, if the developer carrier remains in contact with the photoreceptor for a long period of time, the developer carrier may be deformed. Further, when the process cartridge is transported, the photoreceptor may come into contact with the developer carrying member or the packing material due to vibration or impact, and the photoreceptor may be damaged.

Japanese Unexamined Patent Application Publication No. 2002-100000 discloses a configuration in which a developing sleeve is separated from a photosensitive drum by a spacer arranged between a photoreceptor (photosensitive drum) and a developer carrier (developing sleeve). Furthermore, Patent Document 1 discloses a configuration in which a drum cover that covers a photosensitive drum includes the spacer described above.

Further, Patent Document 2 discloses a process cartridge having a holding member for holding a developing unit having a developer carrier (developing roller) at a separated position where the developing roller is separated from the photosensitive drum.

JP-A-2002-6722 JP 2020-154312 A

When the holding member for holding the developing unit at the separated position is moved due to vibrations and impacts during transportation of the process cartridge, the photoreceptor and the developer carrying member come into contact with each other. SUMMARY OF THE INVENTION An object of the present invention is to provide a cartridge unit capable of suppressing contact between a photoreceptor and a developer carrying member.

One of the inventions according to the present application is
A process cartridge configured to be detachable from an apparatus main body of an image forming apparatus,
a first unit comprising a photoreceptor and a first frame supporting the photoreceptor;
a developer carrier configured to supply developer to the photoreceptor; and a second frame supporting the developer carrier, wherein the developer carrier abuts against the image carrier. a second unit configured to be movable between a contact position and a separation position where the developer carrier is separated from the image carrier;
A holding member supported by the second unit, the holding position holding the second unit at the spaced position with respect to the second frame, and the abutting position of the second unit from the spaced position. a release position to which movement to the position is allowed; a retaining member configured to be movable to;
A moving member configured to be movable between a standby position and an operating position with respect to the second frame, wherein the holding member moves from the operating position to the releasing position in an operating direction. a moving member configured to be movable to
a process cartridge having
a cover member detachably attached to the process cartridge and covering an exposed portion of the photoreceptor exposed to the outside of the process cartridge, the cover member having a movement restricting portion;
has
In the cartridge unit, the movement restricting portion restricts movement of the moving member from the standby position to the operating position when the cover member is attached to the process cartridge.

One of the inventions according to the present application is
A process cartridge configured to be detachable from an apparatus main body of an image forming apparatus,
a first unit comprising a photoreceptor and a first frame supporting the photoreceptor;
a developer carrier configured to supply developer to the photoreceptor; and a second frame supporting the developer carrier, wherein the developer carrier abuts against the image carrier. a second unit configured to be movable between a contact position and a separation position where the developer carrier is separated from the image carrier;
A holding member supported by the second unit, the holding position holding the second unit at the spaced position with respect to the second frame, and the abutting position of the second unit from the spaced position. a release position to which movement to the position is allowed; a retaining member configured to be movable to;
a biasing member that biases the holding member toward the holding position;
a process cartridge having
a cover member detachably attached to the process cartridge and covering an exposed portion of the photoreceptor exposed to the outside of the process cartridge, the cover member having a release restricting portion;
has
In the cartridge unit, the release restricting portion restricts the holding member from moving from the holding position to the releasing position when the cover member is attached to the process cartridge.

According to the present invention, it is possible to provide a cartridge unit that can suppress contact between the photoreceptor and the developer carrier.

1 is a cross-sectional view of a process cartridge according to Embodiment 1; FIG. 1 is a schematic cross-sectional view of an image forming apparatus according to Embodiment 1; FIG. 1 is a cross-sectional view of a process cartridge according to Embodiment 1; FIG. 1 is a cross-sectional view of an image forming apparatus according to Embodiment 1; FIG. 1 is a cross-sectional view of an image forming apparatus according to Embodiment 1; FIG. 1 is a cross-sectional view of an image forming apparatus according to Embodiment 1; FIG. 4 is an exploded perspective view of the drum unit according to Embodiment 1. FIG. 3 is an exploded perspective view of a developing unit according to Embodiment 1. FIG. 1 is an assembled perspective view of a process cartridge according to Embodiment 1. FIG. 1 is a perspective view of a process cartridge according to Embodiment 1. FIG. 1 is an assembled perspective view of a process cartridge according to Embodiment 1. FIG. 1 is a side view of a process cartridge according to Embodiment 1; FIG. 1 is an assembled perspective view of a process cartridge according to Embodiment 1. FIG. 8A and 8B are side views showing the separating operation and the contacting operation of the process cartridge according to the first embodiment; FIG. FIG. 2 is a side view of the process cartridge with some members omitted according to the first embodiment; 2 is an exploded perspective view of a process cartridge and a cover member viewed from the drive side according to Embodiment 1. FIG. 2 is an exploded perspective view of a process cartridge and a cover member viewed from a non-drive side according to Embodiment 1. FIG. FIG. 2 is a perspective view of a state in which a cover member is attached to the process cartridge according to the first embodiment; FIG. 2 is a cross-sectional view of the drive side viewed from the drum unit side according to the first embodiment; 8A and 8B are cross-sectional views showing the separating operation and the contacting operation of the process cartridge according to the second embodiment; FIG. 10 is a cross-sectional view showing a state in which a cover member is attached to the process cartridge according to the second embodiment;

Preferred embodiments of the present invention will be exemplarily described in detail below with reference to the drawings and examples. However, the functions, materials, shapes, relative arrangements, etc. of the components described in this embodiment are not intended to limit the scope of the present invention only to them, unless otherwise specified.

A first embodiment of the present invention will be described below with reference to the drawings. In this embodiment, as an example of an image forming apparatus, an image forming apparatus in which four process cartridges (cartridges) can be attached and detached will be described. However, the number of process cartridges to be mounted in the image forming apparatus is not limited to this, and may be appropriately set as required.

(Schematic configuration of image forming apparatus)
A schematic configuration of the image forming apparatus M will be described with reference to FIGS. 2 and 3. FIG. FIG. 2 is a schematic cross-sectional view of the image forming apparatus M. As shown in FIG. 3 is a sectional view of the process cartridge 100. FIG.

The image forming apparatus M is a four-color full-color laser printer using an electrophotographic method (electrophotographic process), and forms a color image on the recording medium S. FIG. The image forming apparatus M employs a process cartridge system. That is, the process cartridge 100 is detachably attached to the apparatus main body 170 of the image forming apparatus M. As shown in FIG.

Here, regarding the image forming apparatus M, the side on which the front door 11 is provided is the front side (front side), and the side opposite to the front side is the back side (rear side). The right side of the image forming apparatus M is called the drive side, and the left side thereof is called the non-drive side.

Also, when the image forming apparatus M is viewed from the front, the upper side is the upper surface, and the lower side is the lower surface. FIG. 2 is a cross-sectional view of the image forming apparatus M viewed from the non-driving side. side.

Further, the driving side of the process cartridge 100 is the side to which the rotational driving force is transmitted from the apparatus main body 170 to the photosensitive drum 104 as the photosensitive drum in the axial direction (rotational axis direction) of the photosensitive drum 104 as the photosensitive member. The driving side of the process cartridge 100 is the side to which the rotational driving force is transmitted from the apparatus main body 170 to the developing roller 106 in the axial direction (rotation axis direction) of the developing roller 106 as the developer carrying member.

First to fourth process cartridges 100 (100Y, 100M, 100C, 100K) are arranged substantially horizontally in the apparatus main body 170 .

Each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) has the same configuration, and uses different toner colors as developers. A rotational driving force is transmitted from the driving output section of the apparatus main body 170 to the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K).

A bias voltage (charging bias, developing bias, etc.) is supplied from the apparatus main body 170 to each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K).

As shown in FIG. 3, each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) of this embodiment includes a photosensitive drum 104 and charging means acting on the photosensitive drum 104 as process means. has a drum unit 108 with Here, the drum unit 108 may have cleaning means for removing toner from the surface of the photosensitive drum 104 .

Each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) is a developing unit having a developing roller (developing means, developing member) 106 for developing the electrostatic latent image on the photosensitive drum 104. 109. The developing unit 109 has a developing frame 125 and is movably supported with respect to the drum unit 108 .

The first process cartridge 100</b>Y accommodates yellow (Y) toner in the developing frame 125 and forms a yellow toner image on the surface of the photosensitive drum 104 .

The second process cartridge 100</b>M contains magenta (M) toner in the developing frame 125 and forms a magenta toner image on the surface of the photosensitive drum 104 .

The third process cartridge 100</b>C accommodates cyan (C) toner in the developing frame 125 and forms a cyan toner image on the surface of the photosensitive drum 104 .

The fourth process cartridge 100K accommodates black (K) toner in the developing frame 125 and forms a black toner image on the surface of the photosensitive drum 104 .

A laser scanner unit 14 as exposure means is provided above the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K). This laser scanner unit 14 outputs a laser beam U corresponding to image information. Then, the laser light U passes through the exposure window 110 of the process cartridge 100 and scans and exposes the surface of the photosensitive drum 104 .

An intermediate transfer unit 12 as a transfer member is arranged below the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K). The intermediate transfer unit 12 has a flexible transfer belt 12a, a drive roller 12e, a turn roller 12c, and a tension roller 12b. The transfer belt 12a is stretched between a drive roller 12e, a turn roller 12c, and a tension roller 12b.

The photosensitive drums 104 of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) are in contact with the upper surface of the transfer belt 12a. The contact portion is the primary transfer portion. A primary transfer roller 12d is arranged inside the transfer belt 12a. A toner image is transferred from the photosensitive drum 104 to the transfer belt 12a by applying a predetermined voltage to the primary transfer roller 12d.

The secondary transfer roller 6 contacts the transfer belt 12a. A secondary transfer portion is formed between the transfer belt 12 a and the secondary transfer roller 6 . The transfer belt 12a is sandwiched between the secondary transfer roller 6 and the drive roller 12e. A toner image is transferred onto the recording medium S from the transfer belt 12a by applying a predetermined voltage to the secondary transfer roller 6 while the recording medium S is in the secondary transfer portion.

A feeding unit 4 is arranged below the intermediate transfer unit 12 . The feeding unit 4 has a paper feeding tray 4a on which the recording medium S is stacked and a paper feeding roller 4b.

The fixing device 7 and the paper discharge device 8 are arranged in the upper left part of the apparatus main body 170 in FIG. A discharge tray 13 is arranged on the upper surface of the device main body 170 .

After the toner image is fixed on the recording medium S by the fixing device 7 , the recording medium S is discharged to the paper discharge tray 13 .

(Image forming operation)
An image forming operation for forming a color image on the recording medium S will be described.

The photosensitive drums 104 of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) are rotationally driven at a predetermined speed (in the direction of arrow A in FIG. 3). The transfer belt 12a is also rotationally driven at a speed corresponding to the speed of the photosensitive drum 104 (in the direction of arrow C in FIG. 2).

Meanwhile, the laser scanner unit 14 is also driven. In synchronization with the driving of the laser scanner unit 14, the charging roller 105 uniformly charges the surface of the photosensitive drum 104 to a predetermined polarity and potential. The laser scanner unit 14 scans and exposes the surface of the photosensitive drum 104 of each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) with laser light U according to the image signal of each color.

As a result, an electrostatic latent image corresponding to the image signal is formed on the surface of the photosensitive drum 104 . In other words, the photosensitive drum 104 functions as an image carrier that carries an electrostatic latent image. The developing roller 106 is configured to supply developer to the photosensitive drum 104 . The electrostatic latent image is developed by a developing roller 106 that is rotationally driven at a predetermined speed.

Yellow, magenta, cyan, and black toner images are transferred from the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) to the transfer belt 12a.

On the other hand, the recording medium S is separated and fed one by one at a predetermined control timing. The recording medium S is introduced to the secondary transfer portion, which is the contact portion between the secondary transfer roller 6 and the transfer belt 12a, at a predetermined control timing. A four-color toner image on the transfer belt 12a is transferred onto the recording medium S. As shown in FIG.

(Outline of Process Cartridge Attachment/Removal Configuration)
A cartridge tray (hereinafter referred to as tray) 171 that supports the process cartridges will be described with reference to FIGS. 4 to 6. FIG. FIG. 4 is a sectional view of the image forming apparatus M in which the tray 171 is positioned inside the apparatus main body 170 with the front door 11 open. FIG. 5 is a cross-sectional view of the image forming apparatus M with the front door 11 open, the tray 171 positioned outside the apparatus main body 170, and the process cartridge 100 housed inside the tray. FIG. 6 is a cross-sectional view of the image forming apparatus M in which the front door 11 is open, the tray 171 is positioned outside the apparatus main body 170, and the process cartridge 100 is removed from the tray.

As shown in FIGS. 4 and 5, the tray 171 is movable relative to the device main body 170 in the direction of arrow X1 (pushing direction) and the direction of arrow X2 (pulling direction). That is, the tray 171 is provided so as to be able to be pulled out and pushed into the device main body 170, and is configured to be movable in a substantially horizontal direction when the device main body 170 is placed on a horizontal plane. Here, the state in which the tray 171 is positioned outside the apparatus main body 170 (the state in FIG. 5) is called the outer position. A state in which the tray 171 is positioned inside the apparatus main body 170 with the front door 11 open and the photosensitive drum 104 and the transfer belt 12a are separated from each other (state shown in FIG. 4) is referred to as an inner position.

Further, the tray 171 has a mounting portion 171a at an outer position to which the process cartridge 100 can be detachably mounted as shown in FIG. Then, the process cartridge 100 is moved inside the apparatus main body 170 as the tray 171 is moved while being arranged in the mounting portion 171a. At this time, the transfer belt 12a and the photosensitive drum 104 are moved with a gap therebetween. In this embodiment, when the front door 11 is closed, the intermediate transfer unit 12 is lifted in the direction of the arrow Z1 (upward) by a link mechanism (not shown), and is positioned at the image forming position (the photosensitive drum 104 and the intermediate transfer belt 12a). contact). Further, by opening the front door 11, the intermediate transfer unit 12 descends in the direction of the arrow Z2 (downward), separating the photosensitive drum 104 and the intermediate transfer belt 12a. Therefore, the tray 171 can move the process cartridge 100 inside the apparatus main body 170 without the photosensitive drum 104 coming into contact with the transfer belt 12a.

As described above, the plurality of process cartridges 100 can be collectively moved to a position where image formation is possible inside the apparatus main body 170 by using the tray 171 , and can be pulled out collectively to the outside of the apparatus main body 170 . .

(Overall configuration of process cartridge)
The structure of the process cartridge will be described with reference to FIGS. 7 to 10. FIG.

In this embodiment, the first to fourth process cartridges (100Y, 100M, 100C, 100K) have substantially the same configuration except for the color of toner and the amount of toner filled. Therefore, in the following description, one process cartridge 100 out of the first to fourth process cartridges (100Y, 100M, 100C, 100K) will be described.

7 is an exploded perspective view of the drum unit (first unit) 108. FIG. FIG. 8 is an exploded perspective view of the developing unit (second unit) 109. As shown in FIG. FIG. 9 is an assembly perspective view of the process cartridge 100 viewed from the drive side, which is one axial end side of the photosensitive drum 104 . FIG. 10 is a perspective view of the process cartridge 100 viewed from the driving side.

The process cartridge 100 comprises a photosensitive drum 104 and process means acting on the photosensitive drum 104 . Here, the process means includes a charging roller 105 as charging means for charging the photosensitive drum 104, a developing roller 106 as developing means for developing a latent image formed on the photosensitive drum 104, and the like. The process cartridge 100 is divided into a drum unit 108 and a developing unit 109 .

In the following description, the longitudinal direction Y of the drum unit 108 and developing unit 109 is the direction parallel to the rotation axis a of the photosensitive drum 104 (FIG. 9). The longitudinal direction Y is also a direction parallel to the axis of rotation of the developing roller 106 . The longitudinal direction Y is also the longitudinal direction of the process cartridge 100 . The longitudinal direction Y is also the longitudinal direction of cover members 220 and 320, which will be described later.

(Construction of drum unit)
As shown in FIGS. 7 and 9, the drum unit 108 has a photosensitive drum 104, a charging roller 105, and a drum frame 115. As shown in FIG.

The charging roller 105 is rotatably supported by a driving side charging roller bearing 120a and a non-driving side charging roller bearing 121a, and is biased against the photosensitive drum 104 by pressure springs 120b and 121b. The charging roller 105 is supported by the drum frame 115 so as to be rotated by the photosensitive drum 104 .

The photosensitive drum 104 is rotatably supported by a drive-side cartridge cover member 116 and a non-drive-side cartridge cover member 117 provided at both longitudinal ends of the process cartridge 100 . The drive-side cartridge cover member 116 , the non-drive-side cartridge cover member 117 , and the drum frame 115 can be said to be a first frame that supports the photosensitive drum 104 and charging roller 105 . Furthermore, in this embodiment, the first frame of the drum unit 108 is configured to support the developing unit 109 .

As shown in FIG. 9, a coupling member 143 for transmitting driving force to the photosensitive drum 104 is provided at one end of the photosensitive drum 104 in the longitudinal direction (same as the direction of the rotation axis a). The coupling member 143 is engaged with a main body side drum drive coupling 180 (FIGS. 5 and 6) as a drum drive output section of the apparatus main body 170, and the driving force of the drive motor (not shown) of the apparatus main body 170 is applied to the photosensitive drum. It is transmitted to the drum 104 and rotated in the direction of arrow A (FIG. 3). Further, the photosensitive drum 104 has a drum flange 142 on the other longitudinal end side.

(Structure of developing unit)
The developing unit 109 has a developing roller 106, a toner conveying roller 107, a developing blade 130, and a developing frame 125, as shown in FIGS.

The development frame 125 is formed by a lower frame 125a and a lid member 125b. The lower frame 125a and the lid member 125b are joined by ultrasonic welding or the like. The development frame 125 has a toner storage section 129 that stores toner to be supplied to the development roller 106 . Further, the developing frame 125 supports the developing roller 106 and the toner conveying roller 107 via a driving side bearing 126 and a non-driving side bearing 127 . A developing blade 130 for regulating the thickness of the toner layer on the peripheral surface of the developing roller 106 is held. The developing frame 125 , the driving side bearing 126 and the non-driving side bearing 127 can be called a second frame that supports the developing roller 106 , the toner conveying roller 107 and the developing blade 130 .

The developing blade 130 is formed by attaching an elastic member 130b made of sheet metal having a thickness of about 0.1 mm to a support member 130a made of a metal material having an L-shaped cross section by welding or the like. The developing blade 130 is attached to the developing frame 125 with fixing screws 130c at two locations, one end and the other end in the longitudinal direction.

The developing roller 106 includes a metal core 106c and a rubber portion 106d. The developing roller 106 is rotatably supported by a drive-side bearing 126 and a non-drive-side bearing 127 attached to both longitudinal ends of a developing frame 125 .

A development drive input gear 132 for transmitting driving force to the development unit 109 is provided at one end (driving side) of the development unit 109 in the longitudinal direction. The development drive input gear 132 is provided with a development input coupling portion 132a that receives drive from a main body side development drive coupling 185 (FIGS. 5 and 6) of the apparatus main body 170, and drives a drive motor (not shown) of the apparatus main body 170. is input to the developing unit 109 .

The driving force input to the developing unit 109 is transmitted to the developing roller gear 131, thereby rotating the developing roller 106 in the direction of arrow D in FIG. A development cover member 128 that supports and covers the development drive input gear 132 is provided at one longitudinal end (driving side) of the development unit 109 .

Incidentally, the outer diameter of the developing roller 106 is set smaller than the outer diameter of the photosensitive drum 104 . The outer diameter of the photosensitive drum 104 of this embodiment is set within the range of Φ18 to Φ22, and the outer diameter of the developing roller 106 is set within the range of Φ8 to Φ14. Efficient arrangement is possible by setting this outer diameter.

(Assembling the drum unit and developing unit)
Assembly of the drum unit 108 and the developing unit 109 will be described with reference to FIG. The drum unit 108 and the developing unit 109 are connected by a drive-side cartridge cover member 116 and a non-drive-side cartridge cover member 117 provided at both longitudinal ends of the process cartridge 100 .

A drive-side cartridge cover member 116 provided at one longitudinal end of the process cartridge 100 is provided with a developing unit support hole 116 a for supporting the developing unit 109 . Similarly, a non-driving side cartridge cover member 117 provided at the other longitudinal end of the process cartridge 100 is provided with a developing unit support hole 117 a for supporting the developing unit 109 . The developing unit 109 is swingably (movably) supported by the developing unit supporting hole 116a and the developing unit supporting hole 116a.

Further, the drive side cartridge cover member 116 and the non-drive side cartridge cover member 117 are provided with drum support holes 116b and 117b for supporting the photosensitive drum 104, respectively. The photosensitive drum 104 is rotatably supported by the drum support holes 116b and 117b.

The outer diameter portion of the cylindrical portion 128b of the developer cover member 128 is fitted into the developer unit support hole 116a of the drive side cartridge cover member 116 at one end in the longitudinal direction. At the other end in the longitudinal direction, the outer diameter portion of the cylindrical portion (not shown) of the non-driving side bearing 127 is fitted into the developing unit support hole 117a of the non-driving side cartridge cover member 117 . Furthermore, at one end in the longitudinal direction of the photosensitive drum 104 , the end of the photosensitive drum 104 is fitted into the drum support hole 116 b of the driving side cartridge cover member 116 . At the other end of the photosensitive drum 104 in the longitudinal direction, the drum support portion 117b is fitted to the drum flange 142 .

The drive-side cartridge cover member 116 and the non-drive-side cartridge cover member 117 are fixed to the drum frame 115 of the drum unit 108 with screws, adhesive, or the like (not shown). Thereby, the developing unit 109 is rotatably supported by the driving side cartridge cover member 116 and the non-moving side cartridge cover member 117 with respect to the drum unit 108 (photosensitive drum 104).

FIG. 10 shows a state in which the drum unit 108 and the developing unit 109 are assembled by the above steps and integrally formed as the process cartridge 100 .

An axis connecting the center of the developing unit support hole 116a of the driving side cartridge cover member 116 and the center of the developing unit support hole 117a of the non-moving side cartridge cover member 117 is called a swing axis K. Here, the cylindrical portion 128b of the development cover member 128 on the one end side is coaxial with the development input coupling 132a. That is, the developing unit 109 is configured such that the driving force is transmitted from the apparatus main body 170 at this swing axis K. As shown in FIG.

The developing unit 109 is configured to be movable between a contact position where the developing roller 106 contacts the photosensitive drum 104 and a separated position where the developing roller 106 separates from the photosensitive drum 104 . In this embodiment, the developing unit 109 is rotatably connected to the drum unit 108 about the swing axis K. As shown in FIG.

(Description of the separation contact mechanism)
A configuration in which the developing roller 106 of the developing unit 109 separates from and contacts the photosensitive drum 104 of the drum unit 108 will be described with reference to FIGS. 11, 12, and 13. FIG.

FIG. 11 is an assembled perspective view of the process cartridge 100 showing the separation and contact mechanism on the drive side. FIG. 12 is a side view of the process cartridge 100 as seen from the driving side after the regulating member 151R, which will be described later, is assembled. FIG. 13 is an assembly perspective view of the process cartridge 100 showing the non-driving side separation and abutment mechanism.

The process cartridge 100 has a separation contact mechanism on the driving side and the non-driving side. As for the separation contact mechanism, the driving side and the non-driving side have substantially the same function. In the following description, the reference numerals of the members on the driven side and the driving side are the same, and the reference numerals of the members on the driving side are denoted by R, and the reference numerals on the non-driving side are denoted by L. do. When common parts are used for the driven side and the driving side, the letters L and R may be omitted.

The drive-side separation and contact mechanism has a regulating member (holding member) 151R, a moving member 152R, and a tension spring (biasing member) 153. As shown in FIG. The development cover member 128 is provided with a support portion (shaft portion) 128c that supports the regulating member 151R and a support portion (shaft portion) 128k that supports the moving member 151R. The development cover member 128 can be said to be part of the second frame of the development unit 109 .

The supported portion 151Ra, which is a hole, and the supporting portion 128c are fitted to each other, and the restricting member 151R is rotatable around the supporting portion 128c. The moving member 152R is fitted with the supported portion 152Ra, which is an oblong hole, and the support portion 128k, and is rotatable around the support portion 128k and movable in the longitudinal direction of the oblong hole.

The regulation member 151R is supported by the developing unit 109 so as to be movable with respect to the second frame of the developing unit 109. As shown in FIG. Therefore, the regulating member 151R moves together with the developing unit 109 when the developing unit 109 moves between the contact position and the separated position. In particular, when the developing unit 109 moves toward the separated position, the regulating member 151R is configured to move away from the photosensitive drum 104 together with the developing unit 109 .

The separation contact mechanism includes a tension spring 153 that urges the restricting member 151R to rotate in the arrow B1 direction in FIG. 12 about the support portion 128c and urges the moving member 152R in the arrow Z1 direction. The tension spring 153 is a coil spring and an elastic member. The tension spring 153 is assembled by engaging with a spring hooking portion 151Rg provided on the regulating member 151R and a spring hooking portion 152Rs provided on the moving member 152R.

The tension spring 153 applies force in the direction of arrow F2 in FIG. 12 to the spring hooking portion 151Rg of the regulation member 151R, thereby applying a biasing force to rotate the regulation member 151R in the direction of arrow B1.
A tension spring 153 biases the regulating member 151R from the release position toward the holding position.

The tension spring 153 applies a force in the arrow F1 direction to the spring hooking portion 152Rs of the moving member 152R, thereby providing a biasing force to move the moving member 152R in the arrow Z1 direction. A tension spring 153 urges the moving member 152R from the operating position toward the standby position.

Next, the separation contact mechanism on the non-drive side will be described. As shown in FIG. 13, the non-drive-side separation and contact mechanism has a regulating member (holding member) 151L, a moving member 152L, and a tension spring 153. As shown in FIG. The non-drive side bearing 127 is provided with a support portion (shaft portion) 127b that supports the restricting member 151L and a support portion (shaft portion) 127e that supports the moving member 151L. The supported portion 151La and the supporting portion 127b are fitted in the restricting member 151L, and the restricting member 151L can rotate around the supporting portion 127b.
The moving member 152L is rotatable around the supporting portion 127e and movable in the direction of the elongated hole by fitting the supported portion 152La, which is an oblong hole, with the supporting portion 127e.

The regulation member 151L is supported by the developing unit 109 so as to be movable with respect to the second frame of the developing unit 109. As shown in FIG. Therefore, the regulating member 151L moves together with the developing unit 109 when the developing unit 109 moves between the contact position and the separated position. In particular, when the developing unit 109 moves toward the separated position, the regulating member 151L is configured to move away from the photosensitive drum 104 together with the developing unit 109 .

The tension spring 153 is assembled by engaging with a spring hooking portion 151Lg provided on the regulating member 151L and a spring hooking portion 152Ls provided on the moving member 152L. The function of the extension spring 153 on the non-driving side is the same as that on the driving side, so the description is omitted.

(Explanation of separation state and contact state of the process cartridge)
The separated state and contact state of the process cartridge 100 will be described with reference to FIGS. 12, 14 and 15. FIG. FIG. 14 shows only the photosensitive drum 104, the drum frame 115, the driving side cartridge cover member 116, the developing cover member 128, the regulating member 151R, and the moving member 152R.

14A shows a state in which the developing unit 109 is separated from the photosensitive drum 104. FIG.
FIG. 14(b) shows the state when the moving member moves in the Z2 direction. FIG. 14C shows a state in which the developing unit 109 is in contact with the photosensitive drum 104. FIG. FIG. 15 is a side view of the process cartridge 100 with some members omitted. FIG. 15 omits the driving side cartridge cover member 116, the developing device cover member 128, the regulating member 151R, the tension spring 153, and the like.

The regulating member 151R and the regulating member 151L are movable between a holding position where the developing unit 109 is held at the separated position and a release position where movement of the developing unit 109 from the separated position to the contact position is permitted. The moving member 152R and the moving member 152L are configured to be movable with respect to the second frame of the developing unit 109 between a standby position and an operating position.

The operation of the separation contact mechanism will be described below, but since the separation contact mechanism on the drive side and the non-drive side have the same configuration, the explanation will be made using the drive side.

First, the state in which the developing unit 109 is positioned at the separated position will be described. As shown in FIG. 14A, the development unit 109 is held at the separated position by the regulation member 151R being at the holding position. In this state, the abutting portion 151Rc of the regulating member 151R contacts the abutted portion 116c of the drive-side cartridge cover member 116. As shown in FIG. Further, the developing unit 109 is pressed toward the photosensitive drum 104 by the action of a developing pressure spring (not shown) provided on the non-driving side. At this time, the abutting portion 151Rc of the regulating member 151R is pressed toward the abutted portion 116c of the drive-side cartridge cover member 116. As shown in FIG. For this reason, the drive-side cartridge cover member 116 positions the developer cover member 128 via (sandwiching) the regulating member 151R.

In other words, the state in which the regulating member 151R is at the holding position is a state in which the drum unit 108 positions and holds the developing unit 109 via the regulating member 151R. At this time, the developing unit 109 is positioned at the separated position (first position), and the photosensitive drum 104 and the developing roller 106 are separated by a gap P1 (states shown in FIGS. 12 and 14A). On the other hand, the moving member 152R is positioned at the standby position.

From this state, the pushed portion 152Re of the moving member 152R is pushed in the Z2 direction. As a result, the moving member 152R moves from the standby position to the operating position. The protruding portion 152Rh of the moving member 152R moves to the protruding position where it protrudes from the developing frame 125 (state shown in FIG. 14(b)).

When the second force receiving portion 152Rn of the moving member 152R is pressed in the direction of the arrow X2 while the moving member 152R is in the operating position, the moving member 152R rotates in the direction of the arrow BB around the support portion 128k. The regulating member pressing surface 152Rr of the moving member 152R presses the regulated portion 151Re of the regulating member 151R, thereby rotating the regulating member 151R in the arrow B2 direction in FIG. be. That is, the moving member 152R at the operating position moves in the operating direction, thereby moving the restricting member 152R from the holding position to the releasing position. The operating direction is a direction intersecting with the moving direction when the moving member 152R moves from the standby position to the operating position.

When the regulating member 151R rotates in the direction of the arrow B2 and moves to the release position, the contact surface 151Rc separates from the contacted portion 116c of the drive-side cartridge cover member 116, and the developing unit 109 moves from the separation position to the swing axis K. becomes rotatable in the direction of arrow V2. That is, the developing unit 109 rotates in the V2 direction from the separated position, and the developing unit 109 moves to the contact position (second position). At this time, the developing roller 106 contacts the photosensitive drum 104 (state shown in FIG. 14C).

Next, the operation of moving the developing unit 109 from the contact position to the separation position will be described. When the first force receiving portion 152Rk of the moving member 152R is pressed in the direction of the arrow X1 while the developing unit 109 is in the abutting position, the moving member 152R rotates in the direction of the arrow BA, and the bearing pressing surface 152Rq contacts the driving side bearing 126. It abuts against the pressed surface 126c. As a result, the developing unit 109 rotates about the swing axis K in the direction of the arrow V1 and moves to the separated position (state shown in FIG. 15). That is, the moving member 152R at the operating position moves in the direction opposite to the operating direction, thereby moving the restricting member 152R to the release position or the holding position.

When the process cartridge 100 is attached to the apparatus main body 170, the apparatus main body 170 moves the moving member 152R to the operating position. Further, the device body 170 moves the moving member 152R in the operating direction and the direction opposite to the operating direction.

Note that the moving member 152R cannot move in the direction of the arrow X2 unless the moving member 152R is pushed in the direction of the arrow Z2 in the separation contact mechanism of this embodiment. As shown in FIG. 14(a), the developing device cover member 128 has a rib (frame regulating portion) 128g, and the moving member 152R has a surface 152Rg. The rib 128g restricts the moving member 152R from moving in the movement direction. Specifically, before the moving member 152R is pushed in the direction of the arrow Z2 (the moving member 152R is at the standby position), the rib 128g faces the surface 152Rg. Therefore, even if the moving member 152R tries to move in the direction of the arrow X2 in this state, the surface 152Rg interferes with the rib 128g and the moving member 152R cannot move in the direction of the arrow X2. Therefore, the moving member 152R cannot move the restricting member 151R from the holding position to the releasing position.

On the other hand, the moving member 152R is pushed in the arrow Z2 direction to a position where the rib 128g and the surface 152Rg do not face each other, and when it reaches the operating position, the moving member 152R can move in the arrow X2 direction. Therefore, the moving member 152R can move the restricting member 151R from the holding position to the releasing position.

(Description of cover member)
In this embodiment, a cover member (drum cover) 220 is detachably attached to the process cartridge 100 . The process cartridge 100 to which the cover member 220 is attached is called a cartridge unit. The process cartridge 100 is attached to and detached from the apparatus main body 170 with the cover member 220 removed from the process cartridge 100 . Note that mounting of the process cartridge 100 to the apparatus main body 170 may be restricted while the cover member 220 is attached to the process cartridge 100 .

The cover member 220 will be described with reference to FIGS. 1, 3, 10, 16, 17, 18 and 19. FIG. FIG. 1 is a sectional view of the process cartridge 100 taken along NN in FIG. FIG. 16 is an exploded perspective view of the process cartridge 100 and cover member 220 viewed from the drive side. FIG. 17 is an exploded perspective view of the process cartridge 100 and cover member 220 viewed from the non-drive side. FIG. 18 is a perspective view of the process cartridge 100 assembled with the cover member 220 . FIG. 19 is a cross-sectional view of the drive side viewed from the drum unit side perpendicular to the longitudinal direction.

As shown in FIGS. 1, 3, and 10, a portion of the photosensitive drum 104 is exposed outside the process cartridge 100. As shown in FIG. The cover member 220 is attached to the process cartridge 100 so as to cover the exposed portion of the photosensitive drum 104 exposed to the outside of the process cartridge 100 .

As shown in FIGS. 16 and 17, the cover member 220 has driving side engaging portions 220a and 220b at its driving side end and non-driving side engaging portions 220c and 220d at its non-driving side end. there is The driving-side engaging portions 220 a and 220 b are engaged with the engaged portion 116 d of the driving-side cartridge cover member 116 . The non-driving side engaging portion 220c is engaged with the engaged portion 117c of the non-driving side cartridge cover member 117, and the non-driving side engaging portion 220d is engaged with the engaged portion 117d of the driving side cartridge cover member 117. engage with each other. As a result, the cover member 220 is attached to the process cartridge 100 (state shown in FIG. 18).

The cover member 220 has a drum protection portion 220e that protects the exposed portion of the photosensitive drum 104, and separation protection portions 220f and 220g that protect the separation contact mechanisms (regulation members 151R and 151L and moving members 152R and 152L) on both longitudinal ends. have. Specifically, the cover 220 has a separation protection portion 220f arranged on the drive side and a separation protection portion 220g arranged on the non-drive side. Since the separation protection portions 220f and 220g have the same configuration, the separation protection portion 220f arranged on the drive side will be described, and the detailed explanation of the separation protection portion 220R will be omitted.

As shown in FIGS. 1, 16, and 19, the separation protection portion 220f has a first surface (movement restricting portion) 220fa, a second surface 220fb, a third surface 220fc, a fourth surface 220fd, and a fifth surface 220fe. . The cover member 220 has a recess formed by a first surface 220fa, a second surface 220fb, a third surface 220fc, a fourth surface 220fd, and a fifth surface 220fe. are housed.

In this embodiment, when the cover member 220 is attached to the process cartridge 100, the first surface 220fa restricts the movement of the moving member 152R from the standby position to the operating position. As described above, the moving member 152R moves from the operating position in the operating direction, thereby moving the restricting member 151R from the holding position to the releasing position. Therefore, by restricting the movement of the moving member 152R to the operating position, it is possible to prevent the restricting member 151R from being moved to the release position due to vibrations and impacts during transportation.

The first surface 220fa faces the moving member 152R and extends in a direction crossing (preferably orthogonal to) the moving direction Z2 of the moving member 152R.

When the cover member 220 is attached to the process cartridge 100, the first surface 220fa is separated from the moving member 152R in the standby position, and a gap Q is formed between the moving member 152R and the first surface 220fa. is formed. As a result, when the cover member 220 receives an impact or vibration, it is possible to prevent the impact or vibration from being directly transmitted from the cover member 220 to the moving member 152R. When the moving member 152R moves from the standby position toward the operating position, the moving member 152R and the first surface 220fa abut against each other before the moving member reaches the operating position, thereby restricting the movement of the moving member 152R.

As shown in FIG. 14A, the surface 152Rg of the moving member 152R at the standby position and the rib 128g of the developing device cover member 128 face each other across the width H. As shown in FIG. The position of the first surface 220fa in the Z2 direction is set so that the gap Q is smaller than the width H. Movement of the moving member 152R beyond the size of the gap Q is restricted. Therefore, when the cover member 220 is attached to the process cartridge 100 and the moving member 152R is in contact with the first surface 220fa, the surface 152Rg and the rib 128g face each other in the moving direction of the moving member 152R. In this state, the moving member 152R is restricted from moving in the movement direction by the rib 128g, and the moving member 152R is restricted from moving the restricting member 151R from the holding position to the releasing position.

With the cover member 220 attached to the process cartridge 100 as described above, the surface 152Rg of the moving member 152R is maintained at a position facing the rib 128g of the developer cover member 128. FIG.

When the moving member 152R moves in the Z2 direction while the cover member 220 is attached to the process cartridge 100, the moving member 152R interferes with the first surface 220fa and the movement of the moving member 152R is restricted. Specifically, the moving member 152R cannot move beyond the gap Q between the projecting portion 152Rh of the moving member 152R and the first surface 220fa of the cover member 220 .
Therefore, the protruding portion 152Rh of the moving member 152R cannot move to the protruding position protruding from the developing frame 125 either. Therefore, even if the moving member 152R is pressed in the X2 direction, the developing unit 109 will not move to the contact position.

On the other hand, when the cover member 220 is removed from the process cartridge 100, the moving member 152R can move to the operating position. As described above, when the moving member 152R moves in the Z2 direction and the surface 152Rg of the moving member 152R and the rib 128g of the developing device cover member 128 no longer face each other, the restricting member 151R can be moved to the release position.

The third surface 220fc faces the second surface 220fb. The third surface 220fc and the second surface 220fb are arranged at one end and the other end of the first surface 220fa in a direction crossing (preferably orthogonal to) the longitudinal direction.

The third surface (separation regulation portion) 220fc contacts the developing unit 109 when the developing unit 109 positioned at the separated position moves in the direction away from the photosensitive drum 103, thereby preventing the movement of the developing unit 109. is configured to regulate

As shown in FIG. 1, when the developing unit 109 positioned at the separated position by the regulating member 151R moves in the V1 direction (the direction in which the developing roller 106 separates from the photosensitive drum 104) about the swing axis K, the developing cover member A lower end 128h of 128 moves on the trajectory L. FIG. The third surface 220fc is arranged so as to overlap the trajectory L. As shown in FIG. The third surface 220fc interferes with the lower end 128h of the developer cover member 128 when the developer unit 109 tries to rotate further in the V1 direction than the separated position due to impact or vibration applied during transportation. As a result, it is possible to prevent the development unit 109 from being separated excessively and the components of the development unit 109 and the drum unit 108 from colliding with each other.

The cover member 220 has a fourth surface (one end wall) 220fd arranged on one end side of the moving member 152R and a fifth surface (other wall) 220fd arranged on the other end side of the moving member 152R with respect to the rotation axis direction of the photosensitive drum 104 . end wall) 220fe.

The fifth surface 220fe faces the fourth surface 220fd. Longitudinally, the fourth surface 220fd is located inside the spaced abutment mechanism and the first surface 220fa, and the fifth surface 220fe is located outside the spaced abutment mechanism and the first surface 220fa (FIG. 19). The heights of the fourth surface 220fd and the fifth surface 220fe are higher in the Z1 direction than the first force receiving portion 152Rk, the second force receiving portion 152Rn of the moving member 152R, and the regulated portion 151Re of the regulating member 151R. set. Therefore, when viewed in the rotational axis direction of the photosensitive drum 104, the fourth surface 220fd and the fifth surface 220fe overlap at least a portion of the moving member 152R. The fourth surface 220fd and the fifth surface 220fe prevent the developing unit 109 from moving to the contact position due to the user's mistaken operation of the moving member 152R or the regulating member 151R.

As described above, the cover member 220 is provided with the separation protection portion 220f, and the first surface 220fa is arranged on a part of the separation protection portion 220f. As a result, the moving member 152R does not protrude beyond the developing frame 125 due to impact or vibration during transportation or user's operation. Therefore, since the developing unit 109 cannot be moved from the separated position to the contact position by the moving member 152R, contact between the photosensitive drum 104 and the developing roller 106 can be suppressed when the cover member 220 is attached. Therefore, it is possible to prevent image defects due to unintentional contact between the photosensitive drum 104 and the developing roller 106 .

Although the direction in which the first surface 220fa extends is a direction perpendicular to the moving direction Z2 of the moving member 152R, if the movement of the moving member 152R can be restricted, the direction in which the first surface 220fa extends can be It does not have to be orthogonal to the Z2 direction.

The regulating members 151R and 151L are configured to be maintained at the holding position by the tension spring 153 when the cover member 220 is removed from the process cartridge 100. FIG. The moving members 152R and 152L are configured to be maintained at the standby position by the tension spring 153 when the cover member 220 is removed from the process cartridge 100. FIG. In this state, the process cartridge 100 is attached to the apparatus main body 170 . When the process cartridge 100 is attached to the apparatus main body 170, the apparatus main body 170 moves the regulating members 151R and 151L to the holding position and the releasing position.

A process cartridge 200 and a cover member 320 according to a second embodiment of the invention will be described with reference to FIGS. 20 and 21. FIG.

In this embodiment, a cover member (drum cover) 320 is detachably attached to the process cartridge 200 . The process cartridge 200 to which the cover member 320 is attached is called a cartridge unit. The process cartridge 200 is attached to and detached from the apparatus main body 170 with the cover member 320 removed from the process cartridge 200 . Note that mounting of the process cartridge 200 to the apparatus main body 170 may be restricted while the cover member 320 is attached to the process cartridge 200 .

The process cartridge 200 of this embodiment has the same structure as the process cartridge 100 of the first embodiment, but differs in the structure of the separation and contact mechanism. Accordingly, members having the same functions and configurations as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

FIG. 20(a) is a sectional view showing the separated state of the process cartridge 200 according to the second embodiment. FIG. 20(b) is a sectional view showing the contact state of the process cartridge 200 according to the second embodiment. FIG. 21 is a sectional view showing a state where the cover member 320 is attached to the process cartridge 200 according to the second embodiment.

A separation position and a contact position of the developing unit 109 in the second embodiment will be described. A major difference between the separation and contact mechanism of the process cartridge 100 of the first embodiment and the separation and contact mechanism of the process cartridge 200 of the second embodiment is that there is no component corresponding to the moving member 152 .

A state in which the developing unit 109 is at the separated position will be described. As with the regulating member 151R of the first embodiment, the regulating member 251R positions the developing unit 109 at the separated position in this embodiment. That is, the drum unit 108 positions and holds the developing unit 109 via the regulating member 251R (FIG. 20(a)).

The regulating member (holding member) 251R is supported by the developing unit 109 so as to be movable with respect to the second frame of the developing unit 109. As shown in FIG. Therefore, the regulating member 251R moves together with the developing unit 109 when the developing unit 109 moves between the contact position and the separated position. In particular, when the developing unit 109 moves toward the separated position, the regulating member 251R is configured to move away from the photosensitive drum 104 together with the developing unit 109 . In addition to the regulating member 251R, a regulating member similar to the regulating member 251 may be arranged on the non-driven side of the developing unit 109. FIG.

The regulating member 251R is supported by a support portion (shaft portion) 228k of a development cover member 228 (corresponding to the development cover member 128 in the first embodiment). The regulating member 251R can move between a holding position that holds the developing unit 109 at the separated position and a releasing position that allows the developing unit 109 to move from the separated position to the contact position. Specifically, the restricting member 251R is configured to be rotatable in directions B1 and B2 around the support portion 228k. The development cover member 228 can be said to be part of the second frame of the development unit 109 .

In order to hold the developing unit 109 at the separated position, the contact surface 251Rc of the regulating member 251R contacts the contacted portion 116c of the driving side cartridge cover member 116. As shown in FIG. This restricts the rotation of the developing unit 109 about the swing axis K in the direction V2. The developing roller 106 is positioned away from the photosensitive drum 104 .

The operation of moving the developing unit 109 from the separated position to the contact position will be described. When the force receiving portion 252Re of the regulating member 251R is pressed in the arrow X2 direction, the regulating member 251R rotates in the arrow B2 direction. This operation is performed by the apparatus main body 170 when the process cartridge 200 is attached to the apparatus main body 170 . When the regulating member 251R rotates in the direction of arrow B2 and moves from the holding position to the releasing position, the contact surface 251Rc separates from the contacted portion 116c of the drive-side cartridge cover member 116, and the developing unit 109 swings from the separated position. It becomes rotatable about K in the direction of arrow V2. The developing unit 109 at the separated position rotates in the V2 direction, and the developing roller 106 comes into contact with the photosensitive drum 104 .

The regulating member 251R is urged by a tension spring (biasing member) 253 in the arrow B1 direction in FIG. However, when the regulating surface 251Rh of the regulating member 251R abuts against the abutted portion 116c of the drive-side cartridge cover 116, the regulating member 251R is regulated from moving toward the holding position, and the developing unit 109 is maintained at the abutting position. be.

Next, the operation of moving the developing unit 109 from the contact position to the separation position will be described. When the force receiving portion 228k of the development cover member 228 is pressed in the direction of arrow X1 while the development unit 109 is in the contact position, the development unit 109 rotates in the direction of arrow V1. This operation is performed by the apparatus main body 170 when the process cartridge 200 is attached to the apparatus main body 170 . The regulating surface 251Rh of the regulating member 251R is separated from the abutted portion 116c of the driving side cartridge cover 116, and the urging force of the tension spring 253 rotates in the direction of the arrow B1. Then, the contact surface 251Rc moves to a position facing the contacted portion 116c. That is, the regulating member 251R moves from the release position to the holding position. In this state, when the force acting on the force receiving portion 228k disappears, the developing unit 109 rotates in the direction of the arrow V2, and the contact surface 251Rc contacts the contacted portion 116c of the driving side cartridge cover member 116. FIG. As a result, the developing unit 109 is positioned at the separated position.

In such a process cartridge 200, the cover member 320 can prevent the photosensitive drum 104 and the developing roller 106 from unintentionally coming into contact with each other.

The cover member 320 is provided with a second surface (release restricting portion) 320fb that restricts the movement of the restricting member 251R from the holding position to the releasing position when the cover member 320 is attached to the process cartridge 200. .

When the cover member 320 is attached to the process cartridge 200 and the regulating member 251R is in the holding position, the second surface 320fb is separated from the regulating member 251R, and a gap is formed between the regulating members 251R on the second surface 320fb. It is As a result, when the cover member 320 receives an impact or vibration, it is possible to prevent the impact or vibration from being directly transmitted from the cover member 320 to the regulation member 251R.

When the regulating member 251R moves from the holding position toward the releasing position, the second surface 320fb contacts the regulating member 251R before the regulating member 251R reaches the releasing position, thereby releasing the regulating member 251R from the holding position. Restricted from moving to position. A regulated portion 251Re, which is a part of the regulating member 251R, moves along the rotation locus J when the regulating member 251R moves from the holding position to the releasing position. The second surface 320fb is provided so as to be on the locus J of rotation. As a result, the second surface 320fb interferes with the regulated portion 251Re when the regulating member 251R tries to rotate in the direction of the arrow B2 by itself due to impact during transportation, etc., and prevents the regulating member 251R from moving to the release position. prevent.

As described above, the second surface 320fb, which is a part of the separation protection portion 320f of the cover member 320, is provided so as to be on the rotational locus J of the regulated portion 251Re of the regulating member 251R. This prevents the abutting surface 251Rc of the regulating member 251R from separating from the abutted portion 116c of the drive-side cartridge cover member 116 due to an impact during distribution or a user's operation, and the developing unit 109 moving from the separated position to the abutting position. prevent. That is, with the cover member 320 attached to the process cartridge 200, contact between the photosensitive drum 104 and the developing roller 106 can be suppressed. Therefore, it is possible to prevent image defects due to unintentional contact between the photosensitive drum 104 and the developing roller 106 .

Also, the first surface 320a of the cover member 320 extends in a direction intersecting with the second surface 320fb, and covers the regulating member 251R to prevent the regulating member 251R from being operated.

Furthermore, the third surface 220fc to the fifth surface 220fe of the cover member 220 described in the first embodiment can also be applied to the cover member 320 in the second embodiment.

The cover member 320 has a recess formed by a first surface 320fa, a second surface 320fb, a third surface 320fc, a fourth surface 320fd, and a fifth surface 320fe, and a part of the regulating member 251R is accommodated in the recess. .

The third surface (separation regulation portion) 220fc contacts the developing unit 109 when the developing unit 109 positioned at the separated position moves in the direction away from the photosensitive drum 103, thereby preventing the movement of the developing unit 109. is configured to regulate

As shown in FIG. 21, when the developing unit 109 positioned at the separated position by the regulating member 251R moves in the V1 direction (the direction in which the developing roller 106 separates from the photosensitive drum 104) about the swing axis K, the developing cover member A lower end 228h of 228 moves on the trajectory L'. A third surface 320fc (corresponding to the third surface 220fc of the first embodiment) is arranged so as to overlap the trajectory L. As shown in FIG. The third surface 320fc interferes with the lower end 228h of the developer cover member 228 when the developer unit 109 tries to rotate further in the V1 direction than the separated position due to an impact applied during transportation. As a result, it is possible to prevent the development unit 109 from being separated excessively and the components of the development unit 109 and the drum unit 108 from colliding with each other.

The cover member 320 has a fourth surface (one end wall) 320fd arranged on one end side of the regulating member 251R and a fifth surface (other wall) 320fd arranged on the other end side of the regulating member 251R with respect to the rotation axis direction of the photosensitive drum 104 . end wall) 320fe. In FIG. 21, the upper end of the fifth surface 320fe is drawn with a dotted line. In FIG. 21, the positions of the upper end of the fourth surface 320fd and the upper end of the fifth surface 320fe are shifted in order to distinguish between them. However, the upper end of the fourth surface 320fd and the upper end of the fifth surface 320fe may have the same height, or one of them may be higher than the other.

The fifth surface 320fe faces the fourth surface 320fd. With respect to the longitudinal direction, the fourth surface 320fd is positioned inside the spaced abutment mechanism and the first surface 320fa, and the fifth surface 320fe is the spaced abutment mechanism and the first surface 320fa, like the fifth surface 220fe in the first embodiment. located outside the The heights of the fourth surface 320fd and the fifth surface 320fe are set to be higher in the Z1 direction than the regulated portion 251Re of the regulating member 251R. Therefore, when viewed in the rotational axis direction of the photosensitive drum 104, the fourth surface 320fd and the fifth surface 320fe overlap at least a portion of the regulating member 251R. The fourth surface 320fd and the fifth surface 320fe prevent the developing unit 109 from moving to the contact position due to the user's mistaken operation of the moving member 152R or the regulating member 151R.

The regulating member 251</b>R is configured to be maintained at the holding position by the tension spring 253 when the cover member 320 is removed from the process cartridge 200 . In this state, the process cartridge 200 is attached to the apparatus main body 170 . When the process cartridge 200 is attached to the apparatus main body 170, the apparatus main body 170 moves the regulating member 251R to the holding position and the release position.

As described above, according to the present invention, contact of the developing roller 106 with the photosensitive drum 104 can be suppressed.

Reference Signs List 100, 200 process cartridge 104 photosensitive drum 106 developing roller 108 drum unit 109 developing unit 151R, 251R regulating member (driving side)
151L Regulating member (non-drive side)
152R moving member 220, 320 cover member

Claims (12)

A process cartridge configured to be detachable from an apparatus main body of an image forming apparatus,
a first unit comprising a photoreceptor and a first frame supporting the photoreceptor;
a developer carrier configured to supply developer to the photoreceptor; and a second frame supporting the developer carrier, wherein the developer carrier abuts against the image carrier. a contact position;
a second unit configured to be movable to a separation position where the developer carrier is separated from the image carrier;
A holding member supported by the second unit, the holding position holding the second unit at the spaced position with respect to the second frame, and the abutting position of the second unit from the spaced position. a release position to which movement to the position is allowed; a retaining member configured to be movable to;
A moving member configured to be movable between a standby position and an operating position with respect to the second frame, wherein the holding member moves from the operating position to the releasing position in an operating direction. a moving member configured to be movable to
a process cartridge having
a cover member detachably attached to the process cartridge and covering an exposed portion of the photoreceptor exposed to the outside of the process cartridge, the cover member having a movement restricting portion;
has
In a state in which the cover member is attached to the process cartridge, the movement restricting portion is configured to:
A cartridge unit, wherein the moving member is restricted from moving from the standby position to the operating position. In a state in which the cover member is attached to the process cartridge and the moving member is at the standby position, the movement restricting portion is separated from the moving member, and the moving member moves from the standby position to the operating position. a cartridge unit, wherein the movement restricting portion and the moving member come into contact with each other when the cartridge unit is moved by the movement of the cartridge unit. The cover member includes one end wall arranged on one end side of the moving member and the other end wall arranged on the other end side of the moving member with respect to the rotation axis direction of the photoreceptor. 3. A cartridge unit according to claim 1, wherein said one end wall and said other end wall overlap at least a part of said moving member when viewed from above. the second frame has a frame restricting portion that restricts movement of the moving member in the operating direction;
In a state in which the cover member is attached to the process cartridge and the moving member and the movement restricting portion are in contact with each other, the frame restricting portion faces the moving member in the operating direction. A cartridge unit regulated by any one of items 1 to 3. A process cartridge configured to be detachable from an apparatus main body of an image forming apparatus,
a first unit comprising a photoreceptor and a first frame supporting the photoreceptor;
a developer carrier configured to supply developer to the photoreceptor; and a second frame supporting the developer carrier, wherein the developer carrier abuts against the image carrier. a contact position;
a second unit configured to be movable to a separation position where the developer carrier is separated from the image carrier;
A holding member supported by the second unit, the holding position holding the second unit at the spaced position with respect to the second frame, and the abutting position of the second unit from the spaced position. a release position to which movement to the position is allowed; a retaining member configured to be movable to;
a biasing member that biases the holding member toward the holding position;
a process cartridge having
a cover member detachably attached to the process cartridge and covering an exposed portion of the photoreceptor exposed to the outside of the process cartridge, the cover member having a release restricting portion;
has
In a state in which the cover member is attached to the process cartridge, the release restricting portion is configured to:
A cartridge unit, wherein the holding member is restricted from moving from the holding position to the releasing position. In a state in which the cover member is attached to the process cartridge and the holding member is at the holding position, the release restricting portion is separated from the holding member, and the holding member is directed from the holding position to the release position. 6. The cartridge unit according to claim 5, wherein the release restricting portion and the holding member are in contact with each other when the cartridge unit is moved by pressing. The cover member includes one end wall arranged on one end side of the regulating member and the other end wall arranged on the other end side of the regulating member with respect to the rotational axis direction of the photoreceptor. 7. A cartridge unit according to claim 5, wherein said one end wall and said other end wall overlap at least a part of said restricting member when viewed from above. the cover member has a separation regulating portion,
When the second unit positioned at the separated position moves in a direction in which the developer carrying member is separated from the photoreceptor, the separation regulation portion abuts against the second unit to prevent the separation of the second unit. 8. A cartridge unit according to any one of claims 1 to 7, wherein movement is restricted. 9. The cartridge unit according to claim 1, wherein the holding member is configured to be movable together with the second unit in a direction away from the photoreceptor. 10. A cartridge unit according to any one of claims 1 to 9, wherein said second unit is rotatably connected to said first unit. 11. The holding member according to any one of claims 1 to 10, wherein the holding member can be maintained at the holding position with the cover member removed from the process cartridge. Cartridge unit described in section. 12. A cartridge unit according to claim 1, wherein said holding member is rotatably supported by a shaft provided in said second unit.

Images