JP5691416B2 - Charging device, cleaning device, and image forming apparatus - Google Patents

Description

  The present invention relates to a charging device, a cleaning device, and an image forming apparatus.

2. Description of the Related Art In recent years, a charging device that performs corona discharge and includes a cleaning device that cleans components constituting the charging device such as a discharging wire has been proposed.
For example, an apparatus described in Patent Document 1 includes a cleaning member that is in sliding contact with a discharge wire of a corona discharger, a holder that holds the cleaning member, a feed screw that is screwed into a screw portion of the holder and is rotated by a driving unit. And a stopper member for defining both ends of the moving range of the holder.

JP 2005-258018 A

  Even in a charging device including a cleaning device, it is desirable that the relative position of the charging device with respect to the object to be charged does not change before and after cleaning.

According to the first aspect of the present invention, there is provided a charging unit that is disposed along a rotation axis direction of a rotating member to be charged and charges the surface of the member to be charged, and the rotation while contacting a component constituting the charging unit. A cleaning member for cleaning the part by moving in the axial direction and returning to a standby position provided on one end side in the rotational axis direction of the charged body after cleaning, and along the rotational axis direction An applying member for applying a rotational force to the cleaning member by rotating in response to the rotational driving force, a motor for applying the rotational driving force to the applying member, detecting means for detecting a cleaning member, and a control means for controlling driving of the motor, is disposed between the cleaning member and the rotary bearing of the applying member, the cleaning member restrainer hand to restrict the movement of the cleaning member When, and a applying member restricting means for restricting the movement of the applying member, wherein, when returning the cleaning member to the standby position, after the detecting means detects the cleaning member, a predetermined time period A force acting on the applying member when the driving of the motor is stopped after the elapse of time and the movement of the cleaning member is restricted by the cleaning member restricting means even though the applying member gives a moving force; The charging device is characterized in that when the applying member restricting means restricts the movement of the applying member, a force acting on the applying member is attracted.

According to a second aspect of the present invention, when the movement of the cleaning member is restricted by the cleaning member restricting means, a portion where a force acts on the applying member, and the applying member restricting means restricts the movement of the applying member. 2. The charging device according to claim 1, wherein the portion on which the force is applied to the application member is an opposite side across a support member that rotatably supports the application member.
The invention according to claim 3 is characterized in that a recess recessed from an outer peripheral surface is formed in the application member, and the application member restricting means includes a retaining ring fitted into the recess of the application member. The charging device according to claim 1 or 2.

According to a fourth aspect of the present invention, the moving force received by the cleaning member from the applying member and the force received by the cleaning member when the cleaning member restricting means restricts the movement of the cleaning member act on the same axis. The charging device according to claim 1, wherein the charging device is a charging device.
The invention according to claim 5 is characterized in that the cleaning member restricting means is a support member that rotatably supports the applying member, or a member interposed between the support member and the cleaning member. The charging device according to claim 1.

The invention according to claim 6 is arranged along the rotation axis direction of the rotating member to be rotated and moves in the direction of the rotating shaft while being in contact with the parts constituting the charging means for charging the surface of the member to be charged. Then, after cleaning the component, and after cleaning, the cleaning member that returns to the standby position provided on the one end side in the rotation axis direction of the charged body and the rotation member is disposed along the rotation axis direction. Detecting the cleaning member by applying a rotational driving force and applying a rotational force to the cleaning member so as to move in the direction of the rotational axis , a motor for applying a rotational driving force to the provision member, and the cleaning member a detection means, and control means for controlling the driving of the motor, is disposed between the cleaning member and the rotary bearing of the applying member, a cleaning member restricting means for restricting the movement of the cleaning member, wherein the applying unit And a applying member restricting means for restricting the movement of said control means, when returning the cleaning member to the standby position, after the detecting means detects the cleaning member, of the motor after a predetermined period of time When the drive is stopped and the movement of the cleaning member is restricted by the cleaning member restricting means even though the applying member gives the moving force, the force acting on the applying member and the applying member restriction The cleaning device is characterized in that when the means restricts the movement of the applying member, the force acting on the applying member is attracted.

According to a seventh aspect of the present invention, when the movement of the cleaning member is restricted by the cleaning member restricting means, the portion where a force acts on the applying member, and the applying member restricting means restricts the movement of the applying member. The cleaning device according to claim 6, wherein the portion on which the force is applied to the application member is an opposite side across a support member that rotatably supports the application member.
The invention described in claim 8 is characterized in that a recess recessed from an outer peripheral surface is formed in the application member, and the application member restricting means has a retaining ring fitted into the recess of the application member. The cleaning device according to claim 6 or 7.

According to a ninth aspect of the present invention, the moving force received by the cleaning member from the applying member and the force received by the cleaning member when the cleaning member restricting means restricts the movement of the cleaning member act on the same axis. The cleaning device according to claim 6, wherein the cleaning device is a cleaning device.
The invention according to claim 10 is characterized in that the cleaning member restricting means is a support member that rotatably supports the applying member, or a member interposed between the support member and the cleaning member. It is a cleaning apparatus of any one of Claim 6 to 9.

According to an eleventh aspect of the present invention, an image holding body that holds an image, a charging unit that is arranged along a rotation axis direction of the image holding body and charges the surface of the image holding body, and the charging unit are configured. A cleaning member that moves in the direction of the rotation axis while contacting the part to be cleaned and returns to a standby position provided on one end side of the image holding body in the direction of the rotation axis after cleaning. If, rotating the applying member and said applying member for applying a moving force to move the rotation axis direction relative to the cleaning member by rotating by receiving a rotational driving force while being arranged along the rotation axis direction A motor for applying a driving force; a detecting means for detecting the cleaning member; a control means for controlling the driving of the motor; and a rotary bearing of the applying member; and the cleaning member. Move A cleaning member regulating means for regulating, and an applying member restricting means for restricting the movement of the applying member, wherein, when returning the cleaning member to the standby position, the detection means the cleaning member After the detection, the driving of the motor is stopped after the elapse of a predetermined period, and the application is performed when the movement of the cleaning member is restricted by the cleaning member restricting means even though the applying member gives a moving force. The image forming apparatus is characterized in that a force acting on a member and a force acting on the application member when the application member restricting unit restricts the movement of the application member are attracted to each other.

According to the first aspect of the present invention, it is possible to suppress the relative position of the parts constituting the charging means with respect to the member to be charged from changing before and after the cleaning as compared with the case where the present invention is not adopted.
According to the second aspect of the present invention, it is possible to make it difficult for the applying member to bend after cleaning as compared with the case where the present invention is not adopted.
According to the invention of claim 3, the movement of the applying member can be restricted with a simple configuration as compared with the case where the present invention is not adopted.
According to the invention of claim 4, it is possible to make the cleaning member less inclined after cleaning as compared with the case where the present invention is not adopted.
According to the fifth aspect of the present invention, it is possible to realize with a simple configuration that the cleaning member does not easily tilt after cleaning, as compared with the case where the present invention is not adopted.

According to the sixth aspect of the present invention, it is possible to suppress the relative position of the parts constituting the charging means with respect to the member to be charged from changing before and after the cleaning as compared with the case where the present invention is not adopted.
According to the seventh aspect of the present invention, it is possible to make it difficult for the applying member to bend after cleaning as compared with the case where the present invention is not adopted.
According to invention of Claim 8, compared with the case where this invention is not employ | adopted, a movement of a provision member can be controlled with a simple structure.
According to invention of Claim 9, compared with the case where this invention is not employ | adopted, a cleaning member becomes difficult to incline after cleaning.
According to the tenth aspect of the present invention, it can be realized with a simple configuration that the cleaning member is less likely to be tilted after cleaning as compared with the case where the present invention is not adopted.
According to the eleventh aspect of the present invention, it is possible to suppress the relative positions of the parts constituting the charging unit with respect to the image carrier from being changed before and after the cleaning as compared with the case where the present invention is not adopted.

1 is a schematic configuration diagram of an image forming apparatus according to the present embodiment. It is a block diagram which shows schematic structure of a control part. It is sectional drawing of a charging device. It is a figure which shows schematic structure of the cleaning apparatus. It is a perspective view of a cleaning device. It is a schematic block diagram of a movable member. It is a perspective view of a movable member, (a) shows the state when the movable member is moving, and (b) shows the state when the movable member exists in the standby position. It is a figure which shows the cross section of the rotating shaft direction of the photosensitive drum in a cleaning apparatus. A load acting on the movable member when the movable member returns to the standby position is shown. In the comparative configuration, the load acting on the movable member when the movable member returns to the standby position is shown. A load acting on the spiral shaft when the movable member returns to the standby position is shown. In the comparative configuration, the load acting on the spiral shaft when the movable member returns to the standby position is shown.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic configuration diagram of an image forming apparatus according to the present embodiment.
An image forming apparatus 100 according to the present embodiment is provided with a photosensitive drum 11 as an image holding member that is rotatably arranged in an arrow A direction, and a photosensitive drum 11 that is rotatably arranged in an arrow B direction. And an intermediate transfer belt 20 as a transfer material for sequentially transferring (primary transfer) and holding the respective color component toner images formed thereon. In addition, the image forming apparatus 100 includes a secondary transfer unit 30 that collectively transfers (secondary transfer) the superimposed toner image transferred onto the intermediate transfer belt 20 onto a sheet that is a recording material, and the image on which the second transfer has been performed. The image forming apparatus includes a fixing device 50 that fixes the image forming apparatus 100 and a control unit 60 that controls each mechanism unit of the image forming apparatus 100.

  In addition, the image forming apparatus 100 includes a charging device 12 that charges the photosensitive drum 11 around the photosensitive drum 11, and a laser exposure device 13 in which an electrostatic latent image is written on the photosensitive drum 11 (exposure in the drawing). And a rotary developing device 14 that visualizes the electrostatic latent image on the photosensitive drum 11 with toner. The rotary developing device 14 is rotatably mounted with developing units 14Y, 14M, 14C, and 14K that store toner components of yellow (Y), magenta (M), cyan (C), and black (K). Yes. The image forming apparatus 100 also includes a primary transfer roll 15 that transfers each color component toner image formed on the photosensitive drum 11 to the intermediate transfer belt 20 around the photosensitive drum 11, and a residual on the photosensitive drum 11. And a drum cleaner 16 for collecting the toner. The electrophotographic devices such as the charging device 12, the laser exposure device 13, the rotary developing device 14, the primary transfer roll 15, and the drum cleaner 16 are sequentially arranged around the photosensitive drum 11.

The photoconductive drum 11 has a thin cylindrical cylindrical drum made of metal and an organic photosensitive layer formed on the surface of the cylindrical drum. This organic photosensitive layer is made of a material that is negatively charged. The development by the developing units 14Y, 14M, 14C, and 14K is performed by a reversal development method. Accordingly, the toner used in the developing units 14Y, 14M, 14C, and 14K is of the negative charge type.
A charging bias power source 12a for applying a predetermined charging bias is applied to the charging device 12, and a predetermined developing bias is applied to the developing devices 14Y, 14M, 14C, and 14K to the rotary developing device 14. A development bias power supply 14a for performing the above operation is connected to the primary transfer roll 15 and a primary transfer bias power supply 15a for applying a predetermined primary transfer bias is connected to the primary transfer roll 15. The rotary developing device 14 is provided with a developing device drive motor 14b for causing developing devices 14Y, 14M, 14C, and 14K, which are predetermined by rotation, to face the photosensitive drum 11. The photosensitive drum 11 is grounded.

The intermediate transfer belt 20 is stretched over a plurality of (six in this embodiment) rolls 21 to 26. Among these, the rolls 21 and 25 are driven rolls, the roll 22 is a metal idle roll used for positioning the intermediate transfer belt 20 and forming a flat primary transfer surface, and the roll 23 has a constant tension of the intermediate transfer belt 20. The tension roll used for this purpose, the roll 24 is a drive roll for the intermediate transfer belt 20, and the roll 26 is a backup roll for secondary transfer described later. The intermediate transfer belt 20 is made of a resin such as polyimide, polycarbonate, polyester, polypropylene, polycarbonate, polyester, polyethylene terephthalate, acrylic, vinyl chloride, or various rubbers containing carbon black as a conductive agent. The surface resistivity is 10 ¹¹ Ω / □, the volume resistivity is 10 ¹¹ Ω · cm, and the thickness is 150 μm.

  The secondary transfer unit 30 includes a secondary transfer roll 31 disposed on the toner image holding surface side of the intermediate transfer belt 20, a backup roll 26, and the like. The backup roll 26 is a tube of EPDM and NBR blend rubber in which carbon is dispersed on the surface, the inside is made of EPDM rubber, and the surface resistivity is 7 to 10 logΩ / □, and the hardness is, for example, 70 ° ( Asuka C). A secondary transfer bias power source 31a for applying a predetermined secondary transfer bias is connected to the backup roll 26, while the secondary transfer roll 31 is grounded. Further, on the upstream side of the secondary transfer unit 30, a sheet conveyance guide 32 that guides the conveyed sheet (not shown) to the secondary transfer unit 30 is attached.

  Further, the image forming apparatus 100 includes a belt cleaner 27 as a cleaner that removes residual toner adhering to the intermediate transfer belt 20 after the secondary transfer on the downstream side of the secondary transfer unit 30. Further, the image forming apparatus 100 includes a sheet metal member 28 disposed along the inner surface of the intermediate transfer belt 20 at a position facing the belt cleaner 27 with the intermediate transfer belt 20 interposed therebetween.

  The belt cleaner 27 includes a scraper 41 that is formed of a stainless steel plate or the like and is disposed on the image holding surface side of the intermediate transfer belt 20, and a cleaner housing 42 that accommodates the scraper 41. Further, one end side of the scraper 41 is fixed by being sandwiched between blocks 43, and this block 43 is attached to a holder 44 that swings about a shaft 44a. Further, a spring 45 that biases the scraper 41 toward the intermediate transfer belt 20 is attached between a recess 44 b provided on the lower end side of the holder 44 and a bulging portion 42 a provided at the lower portion of the cleaner housing 42. A film seal 46 is attached on the upstream side in the moving direction of the intermediate transfer belt 20 as viewed from the scraper 41 to prevent the removed foreign matter from scattering to the outside.

The holder 44 can be urged or released in a direction opposite to the urging direction of the spring 45 by a cam (not shown) connected to the cleaner drive motor 27a, whereby the scraper 41 is attached to the intermediate transfer belt 20. It is designed to be able to contact and separate. In this embodiment, when a color image composed of a plurality of colors is formed, the secondary transfer roll 31 and the toner image before the final color pass through the secondary transfer roll 31 and the belt cleaner 27. A belt cleaner 27 is separated from the intermediate transfer belt 20.
The fixing device 50 includes a heating roll 51 having a built-in heating source such as a halogen lamp, and a pressure roll 52 arranged in pressure contact with the heating roll 51, and between the heating roll 51 and the pressure roll 52. Fixing is performed by passing a sheet on which a toner image has been transferred to a fixing nip area formed on the sheet.

Next, the control unit 60 will be described.
FIG. 2 is a block diagram illustrating a schematic configuration of the control unit 60.
The control unit 60 includes a CPU 61 that performs arithmetic processing when controlling various motors, a ROM 62 that stores programs executed by the CPU 61, various data, and the like, and a RAM 63 that is used as a work memory for the CPU 61 and the like. It is equipped with. The CPU 61 executes processing while exchanging data with the RAM 63 according to the program stored in the ROM 62. Further, information related to paper output from a user interface (not shown), information related to elapsed time output from the counter 65, and the like are input to the control unit 60 via the input / output interface 64. The control unit 60 also connects the charging bias power source 12a, the developing bias power source 14a, the developing device driving motor 14b, the primary transfer bias power source 15a, the secondary transfer bias power source 31a, the cleaner driving motor 27a, and the like, via an input / output interface 64. The cleaning device drive motor 91 is controlled.

Next, the charging device 12 will be described in detail.
FIG. 3 is a cross-sectional view of the charging device 12.
The charging device 12 has a shield case 71 having a substantially E-shaped cross section that is disposed along the rotation axis direction (longitudinal direction) of the photosensitive drum 11 and has a front opening provided at a portion facing the photosensitive drum 11. doing. The charging device 12 is supported by support members 71 a and 71 b (see FIG. 5) provided at both ends in the longitudinal direction of the shield case 71, that is, the rotation axis direction of the photosensitive drum 11, and is placed inside the shield case 71. Two discharge wires 72 and 73 are stretched. Further, the charging device 12 includes a grid 74 disposed on the front opening side of the shield case 71 so as to face the photosensitive drum 11. The grid 74 is composed of a metal mesh in which a large number of ventilation holes are formed. As the grid 74, in addition to a mesh-like one, for example, a plate material in which many slits are formed can be used.

The discharge wires 72 and 73 are connected to a charging bias power source 12a for applying a DC voltage or a high voltage obtained by superimposing DC and AC. The shield case 71 and the grid 74 are connected to the shield case 71 and the grid 74, respectively. A constant voltage element 76 such as a varistor is connected for the purpose of holding 74 at a predetermined potential.
In the charging device 12 configured as described above, when dirt such as nitrogen oxides generated by discharge adheres to the discharge wires 72 and 73 and the grid 74, the discharge capability is reduced, and the charging potential of the photosensitive drum 11 is reduced. Decreases, leading to image defects. Therefore, the charging device 12 according to the present embodiment includes a cleaning device 80 (see FIG. 4) that removes dirt and the like attached to the discharge wires 72 and 73 and the grid 74 as an example of a charging unit.

FIG. 4 is a diagram illustrating a schematic configuration of the cleaning device 80. FIG. 5 is a perspective view of the cleaning device 80.
The cleaning device 80 includes a brush 81 disposed so as to be in contact with the grid 74, and pads 82 and 83 configured to sandwich the discharge wires 72 and 73. The cleaning device 80 includes a movable member 84 as an example of a cleaning member that holds the brush 81 and the pads 82 and 83 and is movable along the rotation axis direction of the photosensitive drum 11. . A through hole 85 in which a spiral groove 85a is formed is formed in the upper portion of the movable member 84. The specific structure of the movable member 84 will be described in detail later.

Further, the cleaning device 80 has a spiral protrusion 86 a formed around the spiral shaft 86, a spiral shaft 86 that rotates about a rotation axis parallel to the rotation axis direction of the photosensitive drum 11, and the spiral shaft 86. And a rotation drive mechanism 90 for applying a rotation drive force.
The spiral shaft 86 is a bearing (hereinafter, one end portion of the photosensitive drum 11 in the rotation axis direction) formed on the support members 71a and 71b provided at both ends of the shield case 71 in the rotation axis direction. The bearing provided on the side (the back side of the image forming apparatus 100 in the present embodiment) is the “back side bearing 711”, and the bearing provided on the other end side in the rotation axis direction is the “front side”. The bearing is referred to as a bearing 712 ”. A spiral protrusion 86 a formed on the spiral shaft 86 and a spiral groove 85 a formed in the through hole 85 of the movable member 84 are fitted together. In addition, a coupling member 87 for connecting to the rotation drive mechanism 90 is attached to one end of the spiral shaft 86 in the rotation axis direction of the photosensitive drum 11.

  As shown in FIG. 5, the movable member 84 of the cleaning device 80 is normally located at one end side of the charging device 12 in the rotation axis direction of the photosensitive drum 11 and does not hinder the image forming operation. In other words, the image forming apparatus 100 stops at a position on the back side of the image forming apparatus 100 that faces the non-image forming area of the photosensitive drum 11 (hereinafter, this position is referred to as a “standby position”). When the spiral shaft 86 rotates, the movable member 84 receives a driving force from the spiral shaft 86 and moves in the direction of the rotation axis of the photosensitive drum 11. As described above, the spiral shaft 86 functions as an application member that applies power to the movable member 84 to move in the rotation axis direction.

  The rotation drive mechanism 90 includes a cleaning device drive motor 91 that is attached to the main body frame of the image forming apparatus 100 and applies a rotation drive force to the spiral shaft 86. The rotation drive mechanism 90 includes a gear 92 attached to the rotation shaft of the cleaning device drive motor 91, an intermediate gear 93 that meshes with the gear 92, an intermediate gear 94 that is provided coaxially with the intermediate gear 93, A gear 95 that meshes with the gear 94 is provided. A coupling receiving member 96 into which a coupling member 87 attached to the spiral shaft 86 is fitted is attached to the rotation shaft of the gear 95. With this configuration, the rotation driving mechanism 90 transmits the rotation driving force of the cleaning device driving motor 91 to the spiral shaft 86 and applies the rotation driving force to the spiral shaft 86.

FIG. 6 is a schematic configuration diagram of the movable member 84.
As shown in FIG. 6, the movable member 84 includes a base body 841 in which a spiral groove 85 a fitted to the spiral shaft 86 is formed in the upper through hole 85, and the discharge wires 72 among the pads 82 and 83. , 73 from above, an upper pad holding member 842 for holding the upper pads 82a, 83a, and a spring 843 for biasing the upper pad holding member 842. Further, as shown in FIG. 6, the movable member 84 holds the lower pads 82b and 83b sandwiching the discharge wires 72 and 73 from the lower side of the pads 82 and 83 on the upper surface, and holds the grid 74 on the lower surface. The lower pad holding member 844 is provided.

  The base 841 is formed at both ends of a direction orthogonal to the moving direction (the horizontal direction in FIG. 3, in other words, the tangential direction of this circle when a circle on the outer peripheral surface of the photosensitive drum 11 is shown in FIG. 3). A bearing 841a that rotatably supports a rotating shaft 842a provided on the upper pad holding member 842 is provided. Further, the base 841 has a fitting groove 841b into which a convex portion 844a provided in the lower pad holding member 844 is fitted, and a locking hole 841c into which a locking portion 844b provided in the lower pad holding member 844 is fitted. , Is formed. The base body 841 includes a light shielding portion 841d that blocks light emitted from a light emitting element of an optical sensor (not shown) attached to the main body frame of the image forming apparatus 100 (hereinafter simply referred to as “sensor”). Yes. The optical sensor is a well-known photointerrupter sensor, and has two protrusions formed on the sensor body, and a light emitting element (not shown) and a light receiving element (not shown) provided on each of the protrusions. Depending on whether or not the light receiving element receives the light emitted from the light emitting element, the presence of the light shielding portion 841d at the portion where the light emitting element and the light receiving element face each other is read. Then, when the light shielding portion 841d moves with the rotation of the spiral shaft 86 and the light shielding portion 841d blocks the light emitted from the light emitting element of the optical sensor, a pulse signal is sent to the control portion 60.

The spring 843 includes two coil portions 843a formed at both ends in a direction orthogonal to the moving direction, and further includes a coil connecting portion 843b that connects one end portions of the two coil portions 843a, and a coil Two arms 843c connected to the other end of the portion 843a. In the spring 843, the two coil portions 843a are disposed coaxially with the rotation shaft 842a of the upper pad holding member 842, the coil connecting portion 843b is supported by the base body 841, and the two arms 843c are supported by the upper pad holding member. It is attached to the base body 841 while being supported by 842.
As shown in FIG. 6, the lower pad holding member 844 is provided with a convex portion 844a and a locking portion 844b at both ends in a direction orthogonal to the moving direction. Then, the lower pad holding member 844 is fitted into the base body 841 and movable together with the base body 841 by fitting the engaging portion 844b into the engaging hole 841c in the fitting groove 841b formed with the convex portion 844a in the base body 841. The member 84 is configured.

FIG. 7 is a perspective view of the movable member 84, where (a) shows the state when the movable member 84 is moving, and (b) shows the state when the movable member 84 is in the standby position. Show.
As shown in FIG. 7A, when the movable member 84 is moving, the upper pad holding member 842 is moved by the spring force of the spring 843 into the upper pad 82a, 83a and the lower pad holding member 844. It is urged so that 83b may contact. Thus, when the movable member 84 is moving, the discharge wires 72 and 73 are sandwiched between the upper pads 82a and 83a and the lower pads 82b and 83b, respectively. On the other hand, when the movable member 84 is in the standby position, the upper pad holding member 842 is pushed by a protrusion (not shown) provided on the support member 71a, and the rotating shaft 842a is moved against the urging force of the spring 843. Rotates around the center of rotation. Thereby, when the movable member 84 exists in a standby position, the discharge wires 72 and 73 are released.

FIG. 8 is a view showing a cross section in the rotation axis direction of the photosensitive drum 11 in the cleaning device 80.
As shown in FIG. 8, a through-hole 711 a is formed in the back bearing 711, and one end portion of the spiral shaft 86 is passed through the through-hole 711 a, and the tip is deeper than the back bearing 711. Popping out to the side. A coupling member 87 is passed from the tip of one end of the spiral shaft 86, and a first groove 86 b that is recessed from the outer periphery is located on the tip of the coupling member 87. It is formed all around. A first restricting member 861 is fitted in the first groove 86b. Examples of the first restricting member 861 include a retaining ring (ring) having an outer diameter larger than the inner diameter of the coupling member 87, such as a C shape, an E shape, and a U shape.

  On the other hand, an insertion hole 712a is formed in the front side bearing 712 over a predetermined range from the back end surface, and the other end of the spiral shaft 86 is inserted into the insertion hole 712a. . Once the cleaning device 80 is assembled to the charging device 12, the tip of the other end portion of the spiral shaft 86 and the end portion 712b of the insertion hole 712a are formed so as not to contact each other. More specifically, when the spiral shaft 86 moves from the back side of the apparatus to the near side, the tip of the other end portion of the spiral shaft 86 comes into contact with the end portion 712b of the insertion hole 712a before the end of the spiral shaft 86. The movement is restricted when the first restricting member 861 fitted on one end side abuts against the coupling member 87.

  Further, the cleaning device 80 includes a positioning member 88 that is disposed between the movable member 84 and the back bearing 711 and determines the position of the movable member 84. As shown in FIG. 8, the positioning member 88 is formed in a stepped shape in which cylinders having different inner and outer diameters are arranged in the rotation axis direction of the photosensitive drum 11. Then, as shown in FIG. 8, the first cylindrical portion 88a having a relatively small inner diameter and outer diameter is disposed on one end side in the rotation axis direction, and the second inner diameter and the outer diameter are relatively large. The cylindrical portion 88b is disposed on the other end side in the rotation axis direction.

  The spiral shaft 86 has a portion closer to the other end in the direction of the rotation axis than the portion where the first groove 86 b is formed, more specifically, the rotation shaft than the first cylindrical portion 88 a of the positioning member 88. On the other end side in the direction, a second groove 86c that is recessed from the outer periphery is formed on the entire periphery. A second restricting member 862 is fitted into the second groove 86c. The second restricting member 862 can be exemplified by a C-shaped, E-shaped, U-shaped or other retaining ring (ring) whose outer diameter is larger than the outer diameter of the spiral shaft 86. Then, the second restriction member 862 fitted in the second groove 86c restricts the movement of the positioning member 88 in the rotation axis direction. The inner diameter of the second cylindrical portion 88b of the positioning member 88 is larger than the outer shape of the second restricting member 862, and the diameter of the valley of the spiral groove 85a formed in the through hole 85 of the movable member 84 is It is molded to be approximately equivalent. Further, the thickness of the second cylindrical portion 88 b is formed to be thicker than the thickness of the valley of the spiral groove 85 a formed in the through hole 85 of the movable member 84 and the outer shape of the movable member 84. When 84 is abutted against the second cylindrical portion 88b of the positioning member 88, movement to one end portion in the rotation axis direction is restricted. As described above, the positioning member 88 functions as an example of a cleaning member cleaning member regulating unit that regulates the movement of the movable member 84 as an example of the cleaning member. The movement of the movable member 84 toward the one end side in the rotation axis direction (toward the standby position) is regulated by the movable member 84 and the second cylindrical portion 88b of the positioning member 88 abutting each other. The shape of the lower part of the movable member 84 and the shape of the support member 71a of the shield case 71 are determined.

The cleaning device 80 configured as described above operates as follows. That is, when the control unit 60 rotates the cleaning device drive motor 91 in one direction, the spiral shaft 86 rotates in one direction, and the movable member 84 moves from the standby position to the other end side in the rotation axis direction. . At that time, the discharge wires 72 and 73 of the charging device 12 are sandwiched between the pads 82 and 83 of the movable member 84, respectively, and dirt such as nitrogen oxides attached to the discharge wires 72 and 73 is removed. Further, the movable member 84 moves while holding the grid 74 close to the brush 81 so that the brush 81 and the grid 74 of the charging device 12 are in contact with each other, and the nitrogen oxidation attached to the grid 74 by the brush 81 is performed. Dirt such as objects is removed.
Then, after the control unit 60 starts to rotate the cleaning device drive motor 91 in one direction, a predetermined first period (the movable member 84 is determined so as to reach the other end in the rotation axis direction). When the cleaning device drive motor 91 is rotated in the other direction when the time elapses, the spiral shaft 86 rotates in the other direction, and the movable member 84 moves to the standby position from the other end side in the rotation axis direction. Move towards. Then, after the optical sensor detects the light shielding portion 841d of the movable member 84, the control unit 60 stops the cleaning device drive motor 91 after a predetermined second period has elapsed, thereby placing the movable member 84 in the standby position. Exist again. When the movable member 84 is in the standby position, the upper pad holding member 842 is pushed and rotated by a protrusion (not shown) provided on the support member 71a to release the discharge wires 72 and 73, and Release the grid 74 that was hugged.

  Further, in the cleaning device 80 according to the present embodiment, after the control unit 60 detects the light shielding portion 841d of the movable member 84 after the optical sensor detects the cleaning device drive motor 91 after a predetermined second period has elapsed. When the operation is stopped, the movable member 84 and the positioning member 88 come into contact with each other, and the discharge wires 72 and 73 and the grid 74 are released.

  FIG. 9 shows a load acting on the movable member 84 when the movable member 84 returns to the standby position. FIG. 10 shows a load acting on the movable member 84 when the movable member 84 returns to the standby position in the comparative configuration. FIG. 11 shows the load acting on the spiral shaft 86 when the movable member 84 returns to the standby position. FIG. 12 shows the load acting on the spiral shaft 86 when the movable member 84 returns to the standby position in the comparative configuration.

  After the optical sensor detects the light shielding portion 841d of the movable member 84, if the movable member 84 and the positioning member 88 abut before the second period elapses, both members abut until the second period elapses. In this state, a current for rotating the cleaning device drive motor 91 in the other direction is further supplied to the cleaning device drive motor 91. Then, a frictional force is generated between the spiral groove 85a formed on the movable member 84 and the spiral protrusion 86a provided on the spiral shaft 86, and one end portion in the rotation axis direction is generated on the movable member 84. A force toward the side acts on the spiral shaft 86 while a force toward the other end in the rotation axis direction acts.

On the other hand, a force directed to the other end side in the rotation axis direction acts on the movable member 84 at the contact portion with the positioning member 88. The force that the movable member 84 receives from the positioning member 88 and the force that the movable member 84 receives from the spiral shaft 86 are balanced, and the posture of the movable member 84 is determined. Since it occurs on the same axis, the movable member 84 does not tilt. That is, the center line of the through hole 85 of the movable member 84 and the rotational axis direction of the spiral shaft 86 are kept horizontal so as to be parallel.
Here, the movement of the movable member 84 toward one end in the rotation axis direction, for example, the lower portion of the movable member 84 abuts against a portion below the back bearing 711 in the support member 71 a of the shield case 71. Let us consider the comparative structure to be regulated. In this comparative configuration, as shown in FIG. 10, the lower part of the movable member 84 receives a force received from a portion below the back bearing 711 in the support member 71 a of the shield case 71, and the movable member 84 receives from the spiral shaft 86. Due to the force, a moment in the clockwise direction as viewed in FIG. 10 acts on the movable member 84, and the movable member 84 may be inclined. Therefore, in the cleaning device 80 according to the present embodiment, the posture of the movable member 84 is kept more horizontal compared to this comparative configuration. Therefore, bending of the spiral shaft 86, the back side bearing 711, and the front side bearing 712 due to the inclination of the movable member 84 is suppressed. As a result, since the postures of the discharge wires 72 and 73 and the grid 74 do not fluctuate, the surface of the photosensitive drum 11 can be uniformly charged.

Further, the spiral shaft 86 is directed toward the other end side in the rotation axis direction by the force received from the movable member 84, but the first regulating member 861 hits the coupling member 87 and the coupling member 87 is in the back side bearing 711. The movement is restricted by striking on. Thus, the 1st control member 861 functions as an example of the provision member regulation means which regulates the movement of the spiral shaft 86 as an example of the provision member. As shown in FIG. 11, the first restricting member 861 receives from the coupling member 87, and the force exerted on the spiral shaft 86 and the force received by the spiral shaft 86 from the movable member 84 are balanced, and the attitude of the spiral shaft 86 is However, since these forces are in the direction of attracting each other, the spiral shaft 86 does not bend.
Here, the movement of the spiral shaft 86 toward the other end in the rotation axis direction is restricted by the tip of the other end of the spiral shaft 86 abutting against the end 712b of the insertion hole 712a of the near side bearing 712. Consider a comparison configuration. In this comparative configuration, as shown in FIG. 12, the force received by the spiral shaft 86 from the movable member 84 and the tip of the other end side of the spiral shaft 86 are from the end 712b of the insertion hole 712a of the front side bearing 712. Since the received force is a force in a direction facing each other, the spiral shaft 86 may be bent. As a result, the shield case 71 provided with the back bearing 711 and the front bearing 712 supporting the spiral shaft 86 is displaced, and the distance between the photosensitive drum 11 and the grid 74, or the photosensitive drum. 11 and the discharge wires 72 and 73 are varied, and there is a possibility that uniform charging of the surface of the photosensitive drum 11 cannot be performed. Therefore, in the cleaning device 80 according to the present embodiment, the deflection of the spiral shaft 86 is suppressed and the postures of the discharge wires 72 and 73 and the grid 74 do not fluctuate as compared with the comparative configuration. Can be uniformly charged.

  In the above-described embodiment, the positioning member 88 is interposed between the movable member 84 and the back bearing 711, but the configuration is not particularly limited to this. That is, without providing the positioning member 88, the end surface on the other end side in the rotation axis direction of the back bearing 711 is set as the position of the end surface of the second cylindrical portion 88b of the positioning member 88, and the movable member 84 is in the standby position. When returning to the end, the movable member 84 and the end face of the back bearing 711 may abut against each other.

DESCRIPTION OF SYMBOLS 100 ... Image forming apparatus, 11 ... Photosensitive drum, 12 ... Charging device, 20 ... Intermediate transfer belt, 30 ... Secondary transfer part, 50 ... Fixing device, 60 ... Control part, 72, 73 ... Discharge wire, 74 ... Grid , 80 ... cleaning device, 81 ... brush, 82, 83 ... pad, 84 ... movable member, 86 ... spiral shaft, 88 ... positioning member, 90 ... rotational drive mechanism, 861 ... first regulating member, 862 ... second. Regulatory member

Claims (11)

A charging means arranged along the rotation axis direction of the rotating body to be charged to charge the surface of the body to be charged;
The component is cleaned by moving in the direction of the rotation axis while being in contact with the component constituting the charging means, and after being cleaned, the standby is provided on one end side of the charged body in the direction of the rotation axis. A cleaning member returning to the position;
An imparting member that is disposed along the rotational axis direction and that imparts a moving force that moves in the rotational axis direction to the cleaning member by rotating upon receiving a rotational driving force;
A motor for applying a rotational driving force to the application member;
Detecting means for detecting the cleaning member;
Control means for controlling the drive of the motor;
A cleaning member restricting means disposed between the rotating bearing of the applying member and the cleaning member to restrict movement of the cleaning member;
An applying member restricting means for restricting movement of the applying member;
With
The control means, when returning the cleaning member to the standby position, stops the driving of the motor after a predetermined period after the detection means detects the cleaning member,
The force acting on the application member when the movement of the cleaning member is regulated by the cleaning member regulating means even though the application member gives the moving force, and the application member regulating means is the application member. The charging device is characterized in that a force acting on the applying member is attracted when the movement of the charging member is restricted.   When the movement of the cleaning member is restricted by the cleaning member restricting means, the force acts on the applying member, and when the applying member restricting means restricts the movement of the applying member, the force is applied to the applying member. 2. The charging device according to claim 1, wherein the acting part is an opposite side across a supporting member that rotatably supports the applying member. The application member has a recess recessed from the outer peripheral surface,
The charging device according to claim 1, wherein the applying member restricting unit includes a retaining ring that is fitted into the concave portion of the applying member.   The moving force received by the cleaning member from the applying member and the force received by the cleaning member when the cleaning member restricting means restricts the movement of the cleaning member act on the same axis. 4. The charging device according to any one of items 1 to 3.   The said cleaning member control means is a support member which supports the said provision member rotatably, or a member interposed between the said support member and the said cleaning member, The any one of Claim 1 to 4 characterized by the above-mentioned. The charging device according to Item. Cleaning and cleaning the part by moving in the direction of the rotation axis while being in contact with the part constituting the charging means that is arranged along the rotation axis direction of the body to be rotated and charges the surface of the body to be charged A cleaning member that returns to a standby position provided on one end side in the direction of the rotation axis of the member to be charged;
An imparting member that is disposed along the rotational axis direction and that imparts a moving force that moves in the rotational axis direction to the cleaning member by rotating upon receiving a rotational driving force;
A motor for applying a rotational driving force to the application member;
Detecting means for detecting the cleaning member;
Control means for controlling the drive of the motor;
A cleaning member restricting means disposed between the rotating bearing of the applying member and the cleaning member to restrict movement of the cleaning member;
An applying member restricting means for restricting movement of the applying member;
With
The control means, when returning the cleaning member to the standby position, stops the driving of the motor after a predetermined period after the detection means detects the cleaning member,
The force acting on the application member when the movement of the cleaning member is regulated by the cleaning member regulating means even though the application member gives the moving force, and the application member regulating means is the application member. The cleaning device is characterized in that the force acting on the applying member is attracted when the movement of the member is restricted.   When the movement of the cleaning member is restricted by the cleaning member restricting means, the force acts on the applying member, and when the applying member restricting means restricts the movement of the applying member, the force is applied to the applying member. The cleaning device according to claim 6, wherein the acting part is an opposite side across a support member that rotatably supports the application member. The application member has a recess recessed from the outer peripheral surface,
The cleaning device according to claim 6, wherein the applying member restricting unit includes a retaining ring that is fitted into the concave portion of the applying member.   The moving force received by the cleaning member from the applying member and the force received by the cleaning member when the cleaning member restricting means restricts the movement of the cleaning member act on the same axis. The cleaning apparatus of any one of 1-8.   The cleaning member regulating means is a support member that rotatably supports the application member, or a member that is interposed between the support member and the cleaning member. The cleaning device according to item. An image carrier for holding an image;
A charging means arranged along the rotational axis direction of the image carrier to charge the surface of the image carrier;
The component is cleaned by moving in the direction of the rotation axis while being in contact with the component constituting the charging means, and after being cleaned, the standby provided on one end side of the image holding body in the direction of the rotation axis A cleaning member returning to the position;
An imparting member that is disposed along the rotational axis direction and that imparts a moving force that moves in the rotational axis direction to the cleaning member by rotating upon receiving a rotational driving force;
A motor for applying a rotational driving force to the application member;
Detecting means for detecting the cleaning member;
Control means for controlling the drive of the motor;
A cleaning member restricting means disposed between the rotating bearing of the applying member and the cleaning member to restrict movement of the cleaning member;
An applying member restricting means for restricting movement of the applying member;
With
The control means, when returning the cleaning member to the standby position, stops the driving of the motor after a predetermined period after the detection means detects the cleaning member,
The force acting on the application member when the movement of the cleaning member is regulated by the cleaning member regulating means even though the application member gives the moving force, and the application member regulating means is the application member. An image forming apparatus, wherein a force acting on the applying member is attracted when restricting movement of the image forming apparatus.

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