JP2020140095A - Drum cartridge - Google Patents

Abstract

To excellently position a photoreceptor drum in an axial direction.SOLUTION: A drum cartridge 50 comprises a drum flange 110 provided at one end of a photoreceptor drum 51 and rotating integrally with the photoreceptor drum 51, a move member 120 rotating integrally with the drum flange 110 to move in an axial direction with respect to the drum flange 110, and having a movable wall 122, a regulation wall 132 for regulating movement of the movable wall 122, a shaft 150 supported by the regulation wall 132, a first stopper (first snap ring SR1) fixed to one end of the shaft 150, a second stopper (second snap ring SR2) fixed to the other end of the shaft 150, and a biasing member (coil spring CS) provided between the second stopper and the movable wall 122, for biasing the movable wall 122 to the regulation wall 132. A part of the drum flange 110 (wall 111C) is sandwiched between the second stopper and the biasing member.SELECTED DRAWING: Figure 2

Description

The present invention relates to a drum cartridge including a photoconductor drum.

Conventionally, a structure for applying a frictional force to a photoconductor drum has been known in order to suppress a change in the rotation speed of the photoconductor drum due to the influence of a force applied from a developing roller to the photoconductor drum (Patent Documents). 1). Specifically, this structure includes a photoconductor drum, drum flanges fixed to both ends of the photoconductor drum, a pressure disc adjacent to one drum flange in the axial direction of the photoconductor drum, and a pressure disc. Is provided with a spring that presses the drum axially toward one of the drum flanges.

Further, this structure includes two side walls arranged so as to sandwich the photoconductor drum in the axial direction, a shaft connecting the side walls, and a positioning member fixed to the shaft and in contact with the other drum flange. ing. The spring is located between one side wall and the pressure disc.

In this structure, a spring arranged on one end side of the photoconductor drum urges the photoconductor drum in the axial direction, so that the drum flange on the other end side of the photoconductor drum comes into contact with the positioning member, thereby photosensitizing. The body drum is axially positioned.

JP-A-2007-316631

However, in the prior art, since a plurality of members are interposed between the spring for urging the photoconductor drum and the positioning member for determining the position of the photoconductor drum, the urging force for pressing the photoconductor drum against the positioning member is applied. There is a risk that the position of the photoconductor drum may not be well positioned due to variations.

Therefore, an object of the present invention is to provide a drum cartridge capable of satisfactorily positioning the axial position of the photoconductor drum.

In order to solve the above problems, the drum cartridge according to the present invention includes a photoconductor drum, a drum flange provided at one end of the photoconductor drum and rotatable integrally with the photoconductor drum, and the drum flange. A moving member that is rotatable and movable in the axial direction of the photoconductor drum with respect to the drum flange, and includes a movable wall having a surface orthogonal to the axial direction, and the axial direction. A regulation wall that overlaps with the movable wall projected on the above and restricts the movement of the moving member, a shaft that is arranged so as to penetrate the movable wall in the axial direction and is supported by the regulation wall, and fixed to the shaft. A first stopper that regulates the movement of the shaft from at least the restricting wall toward the movable wall, a second stopper fixed to the shaft, and the second stopper and the movable wall. It is provided with an urging member arranged between the movable walls and urging the movable wall toward the regulation wall.
A part of the drum flange is sandwiched between the second stopper and the urging member.

According to this configuration, the urging member arranged on one end side of the photoconductor drum presses a part of the drum flange against the second stopper arranged on one end side of the photoconductor drum, so that the photoconductor drum You can decide the position. That is, since both a contact surface (second stopper) for positioning the photoconductor drum and an urging member for pressing the drum flange against the contact surface are provided on one end side of the photoconductor drum, the photosensitivity is as in the conventional case. Compared to the structure in which the other end of the photoconductor drum is pressed against the frame by the spring placed on one end side of the body drum, the variation in the urging force of the urging member can be suppressed, and the axial position of the photoconductor drum is improved. Can be positioned.

Further, the drum cartridge may further include a friction pad located between the movable wall and the regulation wall.

According to this, an appropriate frictional force can be applied to the photoconductor drum by the friction pad.

Further, the drum cartridge may include a bearing that rotatably supports the photoconductor drum, and the bearing may have the regulation wall.

Further, the drum cartridge includes a bearing that rotatably supports the photoconductor drum and a frame that supports the bearing, and the frame may have the regulation wall.

Further, the urging member may be a coil spring.

Further, the shaft may have conductivity and may be electrically connected to the photoconductor drum.

According to this, the photoconductor drum can be grounded via the shaft.

Further, the shaft may be made of metal.

According to this, it is possible to prevent the shaft from thermally expanding in the axial direction and changing the urging force of the urging member.

Further, one member of the drum flange and the moving member has a protrusion protruding toward the other member, and the other member engages with the protrusion in the rotation direction of the photoconductor drum. Moreover, it may have a guide portion for guiding the protrusion in the axial direction.

Further, the moving member may have a hook for restricting the movement member from coming off the drum flange.

According to this, it is possible to prevent the moving member from coming off the drum flange.

Further, the drum cartridge may further include a coupling into which a driving force for driving the photoconductor drum is input, and the coupling may be provided at the other end of the photoconductor drum.

According to this, since the coupling is provided at the other end of the photoconductor drum that is well positioned in the axial direction, the axial position of the coupling can also be satisfactorily determined. Further, when a driving force is input to the coupling and the photoconductor drum is pressed to one end side, the impact at the time of connection can be absorbed by the urging member arranged on the one end side.

Further, the first stopper is a first snap ring that fits into a first groove formed on the outer peripheral surface of the shaft along the circumferential direction, and the regulation wall is a combination of the first snap ring and the movable wall. It may be located in between.

According to this, the first snap ring, which is the first stopper, can be fixed to the shaft simply by fitting the first snap ring into the first groove of the shaft, so that the work of fixing the first stopper to the shaft is easy. Can be done.

Further, the second stopper may be a second snap ring that fits into a second groove formed on the outer peripheral surface of the shaft along the circumferential direction.

According to this, the second snap ring, which is the second stopper, can be fixed to the shaft simply by fitting the second snap ring into the second groove of the shaft, so that the work of fixing the second stopper to the shaft is easy. Can be done.

Further, the second stopper may be located inside the photoconductor drum.

According to the present invention, the axial position of the photoconductor drum can be satisfactorily positioned.

It is a figure which shows the schematic structure of the color printer provided with the drum cartridge which concerns on one Embodiment of this invention. It is sectional drawing which shows the structure around the photoconductor drum. It is a perspective view which shows the structure of one end side of a photoconductor drum by disassembling. It is a perspective view (a) which shows a drum flange, and is a perspective view (b) which shows a moving member. It is sectional drawing (a) which shows the form which the drum frame has a regulation wall, and the perspective view (b) which shows the bearing in this form. It is a perspective view which shows the modification of the 2nd stopper. It is a perspective view (a), (b) which shows the deformation example of a drum flange and a moving member.

Next, one embodiment of the present invention will be described in detail with reference to the drawings as appropriate.
As shown in FIG. 1, the color printer 1 includes an apparatus main body 10, a top cover 11, a paper feeding unit 20, and an image forming unit 30.

The top cover 11 is a cover that opens and closes the opening 10A formed in the upper part of the apparatus main body 10. The top cover 11 is arranged on the upper part of the apparatus main body 10. The top cover 11 is rotatably provided on the apparatus main body 10 about the rotation shaft 11A. The upper surface of the top cover 11 is a paper ejection tray 11B on which the ejected paper P is placed.

The paper feed unit 20 is provided in the lower part of the apparatus main body 10, and includes a paper feed tray 21 for accommodating the paper P and a paper supply mechanism 22 for supplying the paper P from the paper feed tray 21 to the image forming unit 30. There is. The paper P in the paper feed tray 21 is separated one by one by the paper supply mechanism 22 and supplied to the image forming unit 30.

The image forming unit 30 includes four exposure heads 40, four process cartridge PCs, a transfer unit 70, and a fixing unit 80.

The exposure head 40 has a plurality of LEDs. The exposure head 40 is held by the top cover 11 so as to be suspended from the top cover 11. The exposure head 40 exposes the surface of the photoconductor drum 51 by blinking a plurality of LEDs based on the image data.

Each process cartridge PC is arranged between the top cover 11 and the paper feed tray 21. Each process cartridge PC can be attached and detached through the opening 10A of the apparatus main body 10 with the top cover 11 open. The process cartridge PC includes a drum cartridge 50 and a developing cartridge 60 that can be attached to and detached from the drum cartridge 50.

The drum cartridge 50 includes a cylindrical photoconductor drum 51, a charger 52 for charging the photoconductor drum 51, a pressing spring 53 for urging the developing cartridge 60 toward the photoconductor drum 51, and a cleaning roller 54. It includes a drum frame 55 that supports the photoconductor drum 51 and the like.

The cleaning roller 54 is a roller that removes foreign matter such as toner remaining on the photoconductor drum 51. The cleaning roller 54 is in contact with the photoconductor drum 51 and can rotate.

The developing cartridge 60 includes a developing housing 61 for accommodating toner and a developing roller 62 for supplying the toner in the developing housing 61 to the photoconductor drum 51. The developing roller 62 can rotate while being urged by the photoconductor drum 51 by the pressing spring 53.

The transfer unit 70 is provided between the paper feed tray 21 and the process cartridge PC. The transfer unit 70 includes a drive roller 71, a driven roller 72, an endless transfer belt 73, and four transfer rollers 74. The drive roller 71 and the driven roller 72 support the transport belt 73.

The transport belt 73 is a belt that transports the paper P. The outer surface of the transport belt 73 is in contact with each photoconductor drum 51. Each transfer roller 74 sandwiches a transport belt 73 with each photoconductor drum 51.

The fixing unit 80 includes a heating roller 81 and a pressure roller 82. The pressure roller 82 is pressed by the heating roller 81.

In such an image forming unit 30, first, the charger 52 charges the surface of the photoconductor drum 51. After that, the exposure head 40 exposes the surface of the photoconductor drum 51. As a result, an electrostatic latent image is formed on the photoconductor drum 51.

The developing roller 62 then supplies toner to the electrostatic latent image on the photoconductor drum 51. As a result, a toner image is formed on the photoconductor drum 51.

When the paper P passes between the transport belt 73 and the photoconductor drum 51, the toner image on the photoconductor drum 51 is transferred onto the paper P. After that, the toner image on the paper P is fixed by the fixing unit 80. Next, the paper P is discharged to the paper discharge tray 11B by the discharge roller 91.

As shown in FIGS. 2 and 3, the drum cartridge 50 includes a drum flange 110, a moving member 120, a bearing 130, a friction pad 140, a shaft 150, and a first snap ring SR1 as an example of the first stopper. A second snap ring SR2 as an example of the second stopper, a coil spring CS as an example of the urging member, a drum ground DE, a coupling 160, and a bearing 170 are further provided. In the following description, the axial direction of the photoconductor drum 51 is simply referred to as "axial direction".

The drum flange 110 is provided at one end of the photoconductor drum 51. The drum flange 110 has a fitting portion 111, a flange portion 112, and a small diameter portion 113. Further, the drum flange 110 includes a first hole H1 that opens toward the regulation wall 132 of the bearing 130, which will be described later, a second hole H2 that opens toward the drum ground DE, and a first hole H1 and a second hole H2. It has a wall 111C arranged between them.

The first hole H1 is a hole that supports the moving member 120 so as to be movable in the axial direction. The first hole H1 is formed over a small diameter portion 113, a flange portion 112, and one end portion of the fitting portion 111. The second hole H2 is formed at the other end of the fitting portion 111. The diameter of the second hole H2 is larger than the diameter of the first hole H1.

The wall 111C constitutes the bottom wall of the first hole H1 and the bottom wall of the second hole H2. The wall 111C has a first through hole C1 and a second through hole C2. The first through hole C1 is a hole through which the shaft 150 passes. The second through hole C2 is a hole through which the leg portion 123 of the moving member 120, which will be described later, passes through.

The fitting portion 111 is a substantially cylindrical portion that fits to one end of the photoconductor drum 51. The outer diameter of the fitting portion 111 is substantially the same as the inner diameter of the photoconductor drum 51. The drum flange 110 can rotate integrally with the photoconductor drum 51 by fitting the fitting portion 111 to one end of the photoconductor drum 51.

The flange portion 112 is a portion having a larger diameter than the fitting portion 111. The flange portion 112 protrudes radially outward from the fitting portion 111. The flange portion 112 is in contact with one end of the photoconductor drum 51.

The small diameter portion 113 is a cylindrical portion having a smaller diameter than the flange portion 112. In the present embodiment, the small diameter portion 113 has a smaller diameter than the fitting portion 111. The small diameter portion 113 projects from the flange portion 112 on the side opposite to the fitting portion 111.

The moving member 120 is a member that can rotate integrally with the drum flange 110 and can move in the axial direction with respect to the drum flange 110. The moving member 120 has a cylindrical base portion 121, a movable wall 122 provided at one end of the base portion 121, and a leg portion 123 provided at the other end of the base portion 121.

The movable wall 122 has a surface 122A orthogonal to the axial direction and a through hole 122B penetrating in the axial direction. The through hole 122B is a hole through which the shaft 150 passes.

The base portion 121 has a guide groove 121A as an example of the guide portion. The guide groove 121A is formed on the outer peripheral surface of the base portion 121. The guide groove 121A extends along the axial direction. A plurality of guide grooves 121A are provided at intervals in the circumferential direction of the base portion 121.

As shown in FIGS. 4A and 4B, the drum flange 110 has a protrusion 114 that enters the guide groove 121A of the moving member 120. A number of protrusions 114 are provided corresponding to the plurality of guide grooves 121A. The protrusion 114 protrudes from the inner peripheral surface of the first hole H1 of the drum flange 110. In other words, when the moving member 120 is in the first hole H1 of the drum flange 110, the protrusion 114 projects toward the moving member 120.

With the moving member 120 in the first hole H1 of the drum flange 110, the guide groove 121A engages with the protrusion 114 in the rotational direction of the photoconductor drum 51. Further, when the drum flange 110 moves with respect to the moving member 120, the guide groove 121A guides the protrusion 114 in the axial direction.

The leg portion 123 extends axially from the other end of the base portion 121. A plurality of leg portions 123 are provided at intervals in the circumferential direction of the base portion 121. The leg portion 123 has a hook 123A at its tip. The hook 123A is a portion that restricts the moving member 120 from coming off the drum flange 110.

The above-mentioned second through holes C2 of the drum flange 110 are provided in a number corresponding to a plurality of leg portions 123. The hook 123A can be engaged with the wall 111C in a state where the leg portion 123 is passed through the second through hole C2 (see FIG. 2).

As shown in FIGS. 2 and 3, the bearing 130 has a cylindrical support portion 131, a regulation wall 132 located at one end of the support portion 131, and a base portion 133 located at the other end of the support portion 131. are doing. The support portion 131 rotatably supports the small diameter portion 113 of the drum flange 110. As a result, the bearing 130 rotatably supports the photoconductor drum 51 via the drum flange 110.

The regulation wall 132 is a portion that restricts the movement of the moving member 120. The regulation wall 132 is arranged at a position overlapping the movable wall 122 projected in the axial direction.

The regulation wall 132 has a through hole 132A. The through hole 132A is a hole through which the shaft 150 passes.

The base portion 133 is a plate-shaped portion. The base portion 133 extends from the outer peripheral surface of the support portion 131. The base portion 133 is supported by the holding groove 55A of the drum frame 55.

The photoconductor drum 51 is movable in the axial direction with respect to the bearing 130. Therefore, the photoconductor drum 51 is movable with respect to the drum frame 55 and the bearing 130. In the axial direction, there is a slight gap between the bearing 130 and the flange portion 112 of the drum flange 110, and between the bearing 170 and the flange portion 162 of the coupling 160, which will be described later. In this way, when the axial ends of the flange portions 112 and 162 do not come into contact with the bearings 130 and 170, for example, when the shape of the end portions of the flange portions 112 and 162 is uneven, the photoconductor It is possible to suppress runout (for example, eccentricity) associated with the rotation of the drum 51.

The rotation of the photoconductor drum 51 in the rotation direction of the bearing 130 is regulated by the drum frame 55 or the apparatus main body 10.

The friction pad 140 is a member that applies a frictional force to the moving member 120 when the moving member 120 rotates together with the photoconductor drum 51. The friction pad 140 is located between the movable wall 122 of the moving member 120 and the regulating wall 132 of the bearing 130.

The friction pad 140 has a through hole 141. The through hole 141 is a hole through which the shaft 150 passes.

The friction pad 140 is made of a material that gives a larger frictional force to the moving member 120 than when the movable wall 122 of the moving member 120 is in direct contact with the regulation wall 132 of the bearing 130. The friction pad 140 may be fixed to the regulation wall 132 or the movable wall 122 with an adhesive or the like.

The shaft 150 is made of a conductive material, specifically metal. The shaft 150 is arranged so as to axially penetrate the regulation wall 132 of the bearing 130, the friction pad 140, the movable wall 122 of the moving member 120, and the wall 111C of the drum flange 110.

One end of the shaft 150 is supported by the regulation wall 132. The shaft 150 supports the moving member 120 and the drum flange 110 so as to be movable in the axial direction. The other end of the shaft 150 is in contact with the drum ground DE.

The drum earth DE is a disk-shaped member made of a conductive member such as metal. The drum ground DE has a spring-shaped portion DE1 that is deformable in the axial direction. The shaft 150 is in contact with the spring-shaped portion DE1.

The drum ground DE electrically connects the shaft 150 and the photoconductor drum 51. As a result, the shaft 150 is electrically connected to the photoconductor drum 51 via the drum ground DE. The shaft 150 is grounded via a conductive member (not shown).

The drum ground DE has a plurality of locking pieces DE2 on the outer circumference. The fitting portion 111 of the drum flange 110 has a plurality of engaging grooves 111A corresponding to the plurality of locking pieces DE2. Then, the drum ground DE is held by the drum flange 110 by engaging each locking piece DE2 with each engaging groove 111A.

The shaft 150 has a first groove 151 and a second groove 152. The first groove 151 is formed on the outer peripheral surface of one end of the shaft 150 along the circumferential direction. The second groove 152 is formed on the outer peripheral surface of the other end of the shaft 150 along the circumferential direction.

The first snap ring SR1 is a member that restricts the shaft 150 from moving in the direction from the regulation wall 132 toward the movable wall 122. The first snap ring SR1 is fixed to one end of the shaft 150 by fitting into the first groove 151 of the shaft 150.

The first snap ring SR1 is arranged on the side opposite to the movable wall 122 with respect to the regulation wall 132. That is, the regulation wall 132 is located between the first snap ring SR1 and the movable wall 122 in the axial direction.

The second snap ring SR2 is a member that supports the coil spring CS described later. The second snap ring SR2 is fixed to the other end of the shaft 150 by fitting into the second groove 152 of the shaft 150.

The second snap ring SR2 is located inside the photoconductor drum 51. Specifically, the second snap ring SR2 is located in the second hole H2 of the drum flange 110.

The coil spring CS is a spring that urges the movable wall 122 of the moving member 120 toward the regulation wall 132. The coil spring CS is arranged between the second snap ring SR2 and the movable wall 122 in a state of being contracted by a predetermined amount from the natural length. Specifically, the coil spring CS is arranged between the movable wall 122 and the wall 111C of the drum flange 110.

One end of the coil spring CS is in contact with the movable wall 122. The other end of the coil spring CS is in contact with the wall 111C of the drum flange 110.

The first snap ring SR1 and the second snap ring SR2 sandwich the regulation wall 132, the friction pad 140, the movable wall 122, the coil spring CS, and the wall 111C in the axial direction. That is, the wall 111C, which is a part of the drum flange 110, is sandwiched between the coil spring CS and the second snap ring SR2.

The coupling 160 is a member to which a driving force is input from a driving force output member 210 provided in the apparatus main body 10. The coupling 160 is provided at the other end of the photoconductor drum 51.

Here, the apparatus main body 10 further includes a driving force output member 210 and a driving force transmitting member 220. The driving force transmission member 220 is rotatably supported by the device main body 10. The driving force transmitting member 220 has a gear portion 221 to which a driving force from a motor (not shown) provided in the apparatus main body 10 is input, and a protruding portion 222 protruding from the gear portion 221 in the axial direction.

The driving force output member 210 is supported by a protruding portion 222 of the driving force transmitting member 220 so as to be able to advance and retreat in the axial direction. The driving force output member 210 is engaged with the protruding portion 222 in the rotation direction of the photoconductor drum 51. Since the structure of the engaging portion between the driving force output member 210 and the protruding portion 222 is substantially the same as that of the engaging portion between the moving member 120 and the drum flange 110, the description thereof will be omitted.

A plurality of protrusions 211 for transmitting the driving force to the coupling 160 are provided at the end of the driving force output member 210 on the drum cartridge 50 side. A spring SP is provided between the driving force output member 210 and the driving force transmission member 220.

The driving force output member 210 is movable between a connection position connected to the coupling 160 and a retracted position retracted from the coupling 160. The driving force output member 210 is pressed from the connection position toward the retracted position by a cam (not shown), so that the driving force output member 210 moves from the connection position to the retracted position against the urging force of the spring SP. Further, the driving force output member 210 moves from the retracted position to the contact position by the urging force of the spring SP when the cam is released while the driving force output member 210 is located at the retracted position.

The coupling 160 has a fitting portion 161, a flange portion 162, and a small diameter portion 163.

The fitting portion 161 is a substantially cylindrical portion that fits into the other end of the photoconductor drum 51. The outer diameter of the fitting portion 161 is substantially the same as the inner diameter of the photoconductor drum 51. The coupling 160 can rotate integrally with the photoconductor drum 51 by fitting the fitting portion 161 to one end of the photoconductor drum 51.

The flange portion 162 is a portion having a diameter larger than that of the fitting portion 161. The flange portion 162 projects radially outward from the fitting portion 161. The flange portion 162 is in contact with the other end of the photoconductor drum 51.

The small diameter portion 163 is a columnar portion having a smaller diameter than the flange portion 162. In the present embodiment, the small diameter portion 163 has a smaller diameter than the fitting portion 161. The small diameter portion 163 projects from the flange portion 162 to the side opposite to the fitting portion 161.

The small diameter portion 163 has a groove 163A that engages with the protrusion 211 of the driving force output member 210 in the rotation direction of the photoconductor drum 51.

The bearing 170 has a cylindrical support portion 171 and a base portion 172 extending from the outer peripheral surface of the support portion 171. The support portion 171 rotatably supports the small diameter portion 163 of the coupling 160. As a result, the bearing 170 rotatably supports the photoconductor drum 51 via the coupling 160.

The base portion 172 is a plate-shaped portion. The base portion 172 is supported by the holding groove 55B of the drum frame 55.

The rotation of the photoconductor drum 51 in the rotation direction of the bearing 170 is regulated by the drum frame 55 or the apparatus main body 10.

Next, the action and effect of the drum cartridge 50 according to the present embodiment will be described.
As shown in FIG. 2, when the drum cartridge 50 is mounted on the apparatus main body 10, the drum frame 55 is first positioned in the axial direction with respect to the apparatus main body 10. As a result, the bearing 130 supported by the drum frame 55 is also positioned in the axial direction with respect to the apparatus main body 10. That is, the bearing 130 does not move in the axial direction with respect to the device main body 10, and is held at a predetermined position in the axial direction.

On the other hand, the shaft 150 is restricted from moving in the axial direction toward the coupling 160 side by the first snap ring SR1. Therefore, the second snap ring SR2 located at the other end of the shaft 150 is also restricted from moving in the axial direction toward the coupling 160 side.

Then, the coil spring CS urges the wall 111C of the drum flange 110 against the second snap ring SR2 whose movement to the coupling 160 side is restricted in this way. As a result, the wall 111C of the drum flange 110 is pressed against the second snap ring SR2, so that the drum flange 110 and thus the photoconductor drum 51 are positioned in the axial direction with respect to the apparatus main body 10.

Based on the above, the following effects can be obtained in the present embodiment.
The coil spring CS arranged on one end side of the photoconductor drum 51 presses the wall 111C of the drum flange 110 against the second snap ring SR2 arranged on one end side of the photoconductor drum 51, so that the position of the photoconductor drum 51 is located. Can be decided. That is, both a contact surface (second snap ring SR2) for positioning the photoconductor drum 51 and a coil spring CS for pressing the drum flange 110 against the contact surface are provided on one end side of the photoconductor drum 51. Compared to the structure in which the other end of the photoconductor drum is pressed against the frame by the spring arranged on one end side of the photoconductor drum as described above, the variation in the urging force of the coil spring CS can be suppressed, and the axial direction of the photoconductor drum 51 can be suppressed. The position can be satisfactorily positioned.

Since the friction pad 140 is provided between the movable wall 122 and the regulation wall 132, an appropriate frictional force can be applied to the photoconductor drum 51 by the friction pad 140.

Since the shaft 150 is electrically connected to the photoconductor drum 51, the photoconductor drum 51 can be grounded via the shaft 150.

Since the shaft 150 is made of metal, it is possible to prevent the shaft 150 from thermally expanding in the axial direction and changing the urging force of the coil spring CS.

Since the moving member 120 has the hook 123A, it is possible to prevent the moving member 120 from coming off the drum flange 110.

Since the coupling 160 is provided at the other end of the photoconductor drum 51 that is well positioned in the axial direction, the axial position of the coupling 160 can also be determined satisfactorily. Further, when the driving force output member 210 moves in the axial direction and is connected to the coupling 160 and the photoconductor drum 51 is pressed to one end side, the coil spring CS arranged on one end side exerts an impact at the time of connection. Can be absorbed.

Since the first snap ring SR1 is used as the first stopper, the first snap ring SR1 which is the first stopper can be fixed to the shaft 150 simply by fitting the first snap ring SR1 into the first groove 151 of the shaft 150. it can. Therefore, the work of fixing the first stopper to the shaft 150 can be easily performed.

Since the second snap ring SR2 is used as the second stopper, the second snap ring SR2, which is the second stopper, can be fixed to the shaft 150 simply by fitting the second snap ring SR2 into the second groove 152 of the shaft 150. it can. Therefore, the work of fixing the second stopper to the shaft 150 can be easily performed.

The present invention is not limited to the above embodiment, and can be used in various forms as illustrated below. In the following description, members having substantially the same structure as that of the above embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In the above embodiment, the regulation wall 132 is provided on the bearing 130, but the present invention is not limited to this, and for example, as shown in FIG. 5A, the regulation wall 55C may be provided on the drum frame 55. Specifically, in this embodiment, the bearing 330 has the support portion 131 and the base portion 133 described above, but does not have the regulation wall 132 described above.

And in this form, the drum frame 55 has a regulation wall 55C. The regulation wall 55C is arranged between the first snap ring SR1 and the friction pad 140 in the axial direction.

Even in such a form, the coil spring CS arranged on one end side of the photoconductor drum 51 presses the wall 111C of the drum flange 110 against the second snap ring SR2 arranged on one end side of the photoconductor drum 51. The position of the photoconductor drum 51 can be determined.

In the above embodiment, snap rings SR1 and SR2 have been exemplified as the first stopper and the second stopper, but the present invention is not limited thereto. For example, as shown in FIG. 6, the flange portion 153 integrally formed with the other end of the shaft 150 may be used as the second stopper. Similarly, the first stopper may be a flange portion integrally formed with the shaft.

Further, the stopper may be composed of, for example, two or more parts. Specifically, for example, when a member such as a washer is arranged between the second snap ring SR2 and the wall 111C of the drum flange 110, the member such as the washer and the second snap ring SR2 are second. Configure a stopper.

In the above embodiment, the drum flange 110 is provided with the protrusion 114, and the moving member 120 is provided with the guide groove 121A, but the present invention is not limited thereto. For example, as shown in FIGS. 7A and 7B, the drum flange 110 may be provided with the guide groove 115, and the moving member 120 may be provided with the protrusion 124.

The guide portion is not limited to the guide groove, and for example, a rib extending in the axial direction may be used as the guide portion.

The shaft may be fixed to the regulation wall. In other words, the member for fixing the shaft to the regulation wall may be the first stopper.

In the above embodiment, the coil spring CS is exemplified as the urging member, but the present invention is not limited to this, and the urging member may be, for example, a leaf spring or a torsion spring.

Each element described in the above-described embodiment and modification may be arbitrarily combined and implemented.

50 Drum Cartridge 51 Photoreceptor Drum 110 Drum Flange 111C Wall 120 Moving Member 122 Movable Wall 122A Surface 132 Restriction Wall 150 Shaft CS Coil Spring SR1 1st Snap Ring SR2 2nd Snap Ring

Claims (13)

Photoreceptor drum and
A drum flange provided at one end of the photoconductor drum and rotatable integrally with the photoconductor drum,
A moving member that is rotatable integrally with the drum flange and is movable in the axial direction of the photoconductor drum with respect to the drum flange, and includes a movable wall having a surface orthogonal to the axial direction. When,
A regulation wall that overlaps with the movable wall projected in the axial direction and restricts the movement of the moving member,
A shaft that is arranged so as to penetrate the movable wall in the axial direction and is supported by the regulation wall,
A first stopper fixed to the shaft and restricting the shaft from moving at least in the direction from the restricting wall toward the movable wall.
A second stopper fixed to the shaft and
A part of the drum flange is provided with an urging member arranged between the second stopper and the movable wall and urging the movable wall toward the regulation wall, and a part of the drum flange is attached to the second stopper. A drum cartridge characterized by being sandwiched between a force member. The drum cartridge according to claim 1, further comprising a friction pad located between the movable wall and the regulation wall. A bearing that rotatably supports the photoconductor drum is provided.
The drum cartridge according to claim 1 or 2, wherein the bearing has the regulation wall. A bearing that rotatably supports the photoconductor drum and a frame that supports the bearing are provided.
The drum cartridge according to claim 1 or 2, wherein the frame has the regulation wall. The drum cartridge according to any one of claims 1 to 4, wherein the urging member is a coil spring. The drum cartridge according to any one of claims 1 to 5, wherein the shaft has conductivity and is electrically connected to the photoconductor drum. The drum cartridge according to any one of claims 1 to 6, wherein the shaft is made of metal. One member of the drum flange and the moving member has a protrusion protruding toward the other member.
Any of claims 1 to 7, wherein the other member has a guide portion that engages with the protrusion in the rotation direction of the photoconductor drum and guides the protrusion in the axial direction. The drum cartridge according to item 1. The drum cartridge according to any one of claims 1 to 8, wherein the moving member has a hook for restricting the movement member from coming off the drum flange. Further equipped with a coupling to which the driving force for driving the photoconductor drum is input,
The drum cartridge according to any one of claims 1 to 9, wherein the coupling is provided at the other end of the photoconductor drum. The first stopper is a first snap ring that fits into a first groove formed on the outer peripheral surface of the shaft along the circumferential direction.
The drum cartridge according to any one of claims 1 to 10, wherein the regulation wall is located between the first snap ring and the movable wall. The second stopper according to any one of claims 1 to 11, wherein the second stopper is a second snap ring that fits into a second groove formed on the outer peripheral surface of the shaft along the circumferential direction. Drum cartridge. The drum cartridge according to any one of claims 1 to 12, wherein the second stopper is located inside the photoconductor drum.

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