JP2010271353A - Charger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an charger for properly removing foreign matters adhered on a counter electrode which faces a discharge wire. <P>SOLUTION: The charger includes the discharge wire, extending along a prescribed direction; the counter electrode facing the discharge wire; a frame for supporting the discharge wire and the counter electrode; and a cleaning member 200 for cleaning the counter electrode, by being moved in an extended direction of the discharge wire while being slid on the counter electrode. The cleaning member 200 includes a plate-like member (film 220) brought into contact with the counter electrode and a support member 210 for supporting the plate-like member. The plate-like member includes a tip 221 brought into contact with the counter electrode and a base end 222 positioned on a reverse side to the tip 221. The support member 210 obliquely supports the plate-like member, with respect to the counter electrode so that the tip 221 and the base end 222 of the plate-like member are shifted in the extending direction. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a charger having a cleaning member for cleaning a discharge wire and a counter electrode.

  Conventionally, as a charger, a discharge wire extending in the axial direction of the photosensitive drum, a grid electrode (counter electrode) disposed between the discharge wire and the photosensitive drum, and both the discharge wire and the grid electrode are slidably contacted and cleaned. A thing provided with a cleaning member is known (refer to patent documents 1 and 2).

JP-A-4-369663 Japanese Patent Laid-Open No. 7-301978

  By the way, in the above-described technique, a sponge-like material is usually used for the portion of the cleaning member that is in sliding contact with the grid electrode. However, in such a sponge-like material, a toner or the like fixed on the grid electrode is used. It was difficult to sufficiently remove foreign matter.

  Therefore, an object of the present invention is to provide a charger that can satisfactorily remove foreign matters fixed to a counter electrode (for example, a grid electrode) facing a discharge wire.

  The present invention that solves the above-described problems includes a discharge wire that extends along a predetermined direction, a counter electrode that extends along a direction in which the discharge wire extends and faces the discharge wire, and the discharge wire and the counter And a frame that supports the electrode, and includes a cleaning member that cleans the counter electrode by moving in the extending direction while being in sliding contact with the counter electrode. A plate-shaped member that contacts the counter electrode; and a support member that supports the plate-shaped member, the plate-shaped member having a tip that contacts the counter electrode and a side opposite to the tip A base end located at a position where the plate member is inclined with respect to the counter electrode so that the tip end and the base end are arranged at different positions in the extending direction. It is characterized by supporting.

  Here, “supporting at an angle” means supporting the plate member so that the plate member is inclined with respect to the counter electrode (non-parallel and non-vertical).

  According to the present invention, the foreign matter fixed on the counter electrode can be rubbed and scraped off strongly at the tip of the plate-like member supported diagonally by the support member, so that the foreign matter fixed on the counter electrode can be removed well. be able to.

  According to the present invention, since the tip of the plate-like member that is supported obliquely by the support member is in strong sliding contact with the counter electrode, it is possible to satisfactorily remove the foreign matter adhered to the counter electrode.

1 is a cross-sectional view illustrating an overall configuration of a color printer. It is an expanded sectional view which shows the structure of a process cartridge. It is a perspective view which shows the upper side frame with which the cleaning member was mounted | worn. It is a perspective view which shows the cleaning member. It is a disassembled perspective view which decomposes | disassembles and shows a cleaning member. It is explanatory drawing shown as sectional drawing which looked at the cleaning member from the lower side, and cut the film in the 1st protrusion vicinity. They are the front view (a) which looked at the supporting member from the front end side of the 1st protrusion, and the top view (b) which shows a film. It is a disassembled perspective view which shows the state which attaches the cleaning member to an upper frame. A bottom view (a) of the upper frame with the discharge wire, the counter electrode and the cleaning member removed from the lower side, and an upper frame with the discharge wire, the counter electrode and the cleaning member attached are shown in FIG. 9 (a). It is XX sectional drawing (b) cut | disconnected by the XX line. It is sectional drawing which shows the state which the cleaning member and the upper side frame contact | abutted. It is explanatory drawing (a), (b) which shows the modification which affixed the sliding contact member for counter electrodes on the front-end | tip of a plate-shaped member.

  Next, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the following description, first, the overall configuration of the color printer will be briefly described, and then the characteristic part of the present invention will be described.

  In the following description, the direction will be described with reference to the user when using the color printer. That is, in FIG. 1, the left side toward the paper surface is “front side (front side)”, the right side toward the paper surface is “rear side (back side)”, the back side toward the paper surface is “left side”, and it faces the paper surface. Let the near side be the “right side”. In addition, the vertical direction toward the page is defined as the “vertical direction”.

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

  An upper cover 12 that can be opened and closed is provided on the upper portion of the main body housing 10 so as to be rotatable up and down with a hinge (not shown) provided on the rear side as a fulcrum. The upper surface of the upper cover 12 serves as a paper discharge tray 13 that accumulates the paper P discharged from the main body housing 10, and a plurality of holding members 14 that hold a plurality of LED units 40 described later are provided on the lower surface. ing.

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

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

  The process cartridge 50 is arranged side by side in the front-rear direction between the upper cover 12 and the paper feed unit 20, and as shown in FIG. 2, the photosensitive cartridge 51 and a developing cartridge that can be attached to and detached from the photosensitive cartridge 51. 61. Each process cartridge 50 has the same configuration except that the color of the toner stored in the toner storage chamber 66 of the developing cartridge 61 is different.

  The photoconductor cartridge 51 mainly includes a drum case 52 and a photoconductive drum 53 and a charger 54 as an example of a photoconductor accommodated in the drum case 52.

  The developing cartridge 61 includes a developing case 62, a developing roller 63 accommodated in the developing case 62, a supply roller 64 and a blade assembly 65, and a toner accommodating chamber 66 formed in the developing case 62. .

  As shown in FIG. 1, the transfer unit 70 is provided between the paper feeding unit 20 and each process cartridge 50, and mainly includes a drive roller 71, a driven roller 72, a conveyance belt 73, and a transfer roller 74.

  The driving roller 71 and the driven roller 72 are arranged in parallel with a distance in the front-rear direction, and a conveying belt 73 formed of an endless belt is stretched between them. The outer surface of the conveyance belt 73 is in contact with each photosensitive drum 53. In addition, four transfer rollers 74 that sandwich the conveyor belt 73 between the photosensitive drums 53 are arranged inside the conveyor belt 73 so as to face the photosensitive drums 53. A transfer bias is applied to the transfer roller 74 by constant current control during transfer.

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

  In the image forming unit 30 configured as described above, first, the surface of each photosensitive drum 53 is uniformly charged by the charger 54 and then exposed to light emitted from each LED unit 40. As a result, the potential of the exposed portion is lowered, and an electrostatic latent image based on the image data is formed on each photosensitive drum 53.

  Further, the toner in the toner storage chamber 66 is supplied to the developing roller 63 by the rotation of the supply roller 64, and enters the space between the developing roller 63 and the blade assembly 65 by the rotation of the developing roller 63 and is thin with a certain thickness. It is carried on the developing roller 63 as a layer.

  The toner carried on the developing roller 63 is supplied to the electrostatic latent image formed on the photosensitive drum 53 when the developing roller 63 comes into contact with the photosensitive drum 53. As a result, the toner is selectively carried on the photosensitive drum 53 to visualize the electrostatic latent image, and a toner image is formed by reversal development.

  Then, the paper P supplied onto the conveyor belt 73 passes between each photosensitive drum 53 and each transfer roller 74 disposed inside the conveyor belt 73, whereby the toner formed on each photosensitive drum 53 is obtained. The image is transferred onto the paper P. When the paper P passes between the heating roller 81 and the pressure roller 82, the toner image transferred onto the paper P is thermally fixed.

  The paper discharge unit 90 includes a paper discharge side conveyance path 91 that extends upward from the exit of the fixing unit 80 and is reversed to the front side, and a plurality of pairs of conveyance rollers 92 that convey the paper P. Yes. The paper P on which the toner image has been transferred and heat-fixed is transported through a paper discharge-side transport path 91 by a transport roller 92, discharged outside the main body housing 10, and accumulated in the paper discharge tray 13.

<Charger structure>
Next, the structure of the charger 54 will be described in detail.
As shown in FIG. 2, the charger 54 includes an upper frame 100 as an example of a frame constituting the upper portion of the drum case 52, a discharge wire 110 and a counter electrode 120 supported by the upper frame 100, The cleaning member 200 shown in FIG.

  The discharge wire 110 is a wire that extends along the axial direction (predetermined direction) of the photosensitive drum 53, and is disposed in a long groove 101 (see FIG. 3) formed in the upper frame 100, and both ends thereof are arranged on the upper frame. 100.

  The counter electrode 120 is a plate-like electrode that extends along the axial direction of the photosensitive drum 53 and is bent in a U-shape in cross section so as to face the discharge wire 110, and mainly includes the grid electrode 121 and a pair of And a shield electrode 122.

  The grid electrode 121 is an electrode disposed between the discharge wire 110 and the photosensitive drum 53, and is formed into a plurality of wires by forming a plurality of slits at the bottom of the U-shaped counter electrode 120. .

  Each shield electrode 122 is arranged to face (position) so as to sandwich the discharge wire 110 in the moving direction of the photosensitive drum 53. Here, the “moving direction of the photosensitive drum 53” refers to the moving direction of the portion of the photosensitive drum 53 that faces the grid electrode 121 (in FIG. 2, diagonally upward).

  As shown in FIG. 3, the cleaning member 200 is movably mounted in the long groove 101 of the upper frame 100, and moves while sliding on the discharge wire 110 and the counter electrode 120 (see FIG. 2). The wire 110 and the counter electrode 120 are cleaned. Specifically, as illustrated in FIG. 4, the cleaning member 200 includes a support member 210, a film 220 as an example of a plate-like member, and a plate-like sponge 230 as an example of a sliding contact member.

  As shown in FIG. 5, the support member 210 mainly includes an operation portion 211 formed in a substantially rectangular flat plate shape and two arm portions 212 that can be bent and deformed downward from the lower surface of the operation portion 211. Yes. Each arm portion 212 is formed with a first protrusion 213, a second protrusion 214, and a recess 215 for supporting the film 220 and the plate-like sponge 230.

  Each first protrusion 213 is formed in a substantially triangular prism shape, and supports the film 220 in a state of penetrating through an engagement hole 227 formed in the film 220. More specifically, each first protrusion 213 supports one side and the other side of the film 220 separated by the slit 226. In addition, the first protrusion 213 contributes to suppressing both ends of the plate-like sponge 230 bent in a substantially U shape from spreading in a direction away from each other.

  Each of the second protrusions 214 is formed in a quadrangular prism shape, and supports the bent portion of the substantially U-shaped plate-like sponge 230 so as to sandwich it.

  The concave portion 215 is formed so as to surround the first protrusion 213 and is formed so as to gradually become deeper from the distal end of the arm portion 212 toward the proximal end. That is, the recess 215 has an inclined surface that gradually inclines toward one side in the longitudinal direction of the operation unit 211 from the distal end of the arm portion 212 toward the proximal end. As a result, the film 220 pressed against the recess 215 is inclined with respect to the grid electrode 121 so that the distal end 221 and the proximal end 222 are displaced in the extending direction of the discharge wire 110 (disposed at different positions). In this state, it is supported by the support member 210 (see FIG. 10).

  Of the opening ends 215A and 215B (see FIG. 6) of the recess 215 disposed so as to sandwich the first protrusion 213, the opening end 215A located outside the first protrusion 213 is more than the opening end 215B located inside. Is formed so as to be arranged at a higher position (position on the film 220 side than the arm part 212 in the extending direction). As a result, as shown in FIG. 6, the film 220 pressed against the recess 215 is curved when viewed from the direction connecting the distal end 221 and the proximal end 222. In other words, the film 220 is curved in a cylindrical shape so that the central portion where the slit 226 is formed is recessed toward the recess 215 rather than the both side ends 223 of the film 220.

  In FIG. 6, only the film 220 is shown as a cross-sectional view cut in the vicinity of the first protrusion 213 so that the curved state of the film 220 can be easily understood.

  As shown in FIG. 5, the film 220 is a PET film that can be flexibly deformed, and includes a distal end 221 that contacts the grid electrode 121 (see FIG. 2) and a proximal end 222 that is located on the opposite side of the distal end 221. And a pair of side ends 223 facing (positioning) in a direction orthogonal to the direction connecting the distal end 221 and the base end 222. The pair of side ends 223 are brought into pressure contact with the pair of shield electrodes 122 (see FIG. 2) when the cleaning member 200 is attached to the upper frame 100. Thereby, the film 220 curved by the above-mentioned recessed part 215 is further curved.

  A notch 224 is formed between the front end 221 and both side ends 223 of the film 220. As a result, the leading end 221 and both side ends 223 of the film 220 are not affected by each other's bending, so that the leading end 221 and both side ends 223 of the film 220 are brought into contact with the grid electrode 121 and each shield electrode 122 with high accuracy. Can be done.

The film 220 has a hole 225 through which the discharge wire 110 (see FIG. 2) passes, and a slit 226 along the extending direction of the discharge wire 110 so as to pass through the hole 225 to the tip 221. Is formed. The hole 225 is formed in a shape that is not line symmetric with respect to the slit 226. Thereby, for example, it is possible to prevent erroneous assembly such that the front and back of the film 220 are mistaken by visual observation, and to prevent a good assembly due to burrs formed at the edges of the holes 225 and the like.
In order to prevent erroneous assembly, instead of devising the shape of the hole 225, the left first protrusion 213 and the right first protrusion 213 are formed to have different shapes and matched to these shapes. You may form so that the shape of each engagement hole 227 mentioned later may differ. In addition, a configuration for preventing misassembly (for example, in the support member 210, a protrusion is provided only on one of the left and right sides of the slit 226, and a hole into which the protrusion enters is formed in the film 220). Also good.

  Furthermore, the film 220 is formed with an engagement hole 227 formed symmetrically with respect to the slit 226 so as to sandwich the slit 226. As shown in FIGS. 7A and 7B, the engagement hole 227 has three corners 227A, 227B, which engage with the three corners 213A, 213B, 213C of the first protrusion 213 of the support member 210. 227C.

  The three corners 227A, 227B, and 227C are formed at positions rotated by a slight angle from the positions of the three corners 213A, 213B, and 213C. Specifically, the direction of this rotation is the direction in which the slit 226 opens (the direction in which one side separated by the slit 226 and the other separated from each other around the base end 222 of the film 220 move in an arc shape). Is the opposite direction.

  More specifically, the three corners 227A, 227B, 227C on the left side of the figure are formed at positions rotated counterclockwise in the figure from the positions of the three corner parts 213A, 213B, 213C on the left side of the figure. Further, the three corners 227A, 227B, 227C on the right side of the figure are formed at positions rotated clockwise from the position of the three corner parts 213A, 213B, 213C on the right side of the figure. Thereby, when each engagement hole 227 of the film 220 is attached to the first protrusion 213 of the support member 210, each corner 227A, 227B, 227C moves to the position of each corner 213A, 213B, 213C. By matching, the slit 226 is slightly opened (see FIG. 4). That is, the slit 226 is configured to open depending on the difference in the shape of the attachment portion (each first protrusion 213 and each engagement hole 227) between the arm portion 212 and the film 220.

  As shown in FIG. 5, the plate-like sponge 230 is a member that is slidably contacted with the discharge wire 110 (see FIG. 2) in the extending direction, and each of the support members 210 is bent in a substantially U shape. It is clamped by the second protrusion 214. Then, the film 220 is sandwiched between the plate-like sponge 230 and the support member 210 by being sandwiched between the second protrusions 214 in this way.

  As shown in FIG. 8, a pair of engagement walls 102 (only one is shown) formed so as to protrude from a pair of side walls forming the long groove 101 is formed on one end side of the long groove 101 of the upper frame 100. ing. The engaging wall 102 comes into contact with each notch 224 of the film 220 when the cleaning member 200 is attached to the long groove 101, whereby the slit 226 of the film 220 is further opened and the hole 225 is opened. It is possible to allow the discharge wire 110 to enter smoothly.

  Further, as shown in FIGS. 9A and 9B, a pair of tapers that push the arm portions 212 (second projections 214) of the support member 210 toward each other in the long groove 101 of the upper frame 100. A surface 103 is formed. Accordingly, after inserting the cleaning member 200 from one end side (engagement wall 102 side) of the long groove 101, the arm member of the support member 210 is slid to the other end side as shown in FIG. 9B. 212 approaches and the slit 226 of the film 220 closes. Specifically, the pair of tapered surfaces 103 push each arm portion 212 (each second protrusion 214) in the approaching direction, and the two corner portions 213A and 213D (each of the first protrusions 213 provided integrally with each arm portion 212). 7) presses the two corners 227A and 227D of each engagement hole of the film 220 inward, so that the slit 226 of the film 220 is closed. As a result, when the cleaning member 200 is positioned at the cleaning position for cleaning the grid electrode 121, the slit 226 is closed and slidably contacts the entire grid electrode 121, so that the grid electrode 121 can be cleaned well. It has become. Further, the plate-like sponge 230 (see FIG. 4) is pressed and contracted by approaching the arm portions 212 of the support member 210 in this way, so that the discharge wire 110 is strongly rubbed with the plate-like sponge 230 to improve cleaning. It is possible to do it.

  Further, as shown in FIG. 10, the leading end 221 of the film 220 reaches a part of the upper frame 100 (specifically, the regulating portion 104 that regulates the discharge of the grid electrode 121) on the other end side of the upper frame 100. At the same time, a locking portion 105 that contacts the support member 210 is provided. More specifically, a minute gap is formed between the leading end 221 of the film 220 and the restricting portion 104 when the support member 210 is in contact with the locking portion 105.

  Accordingly, when the cleaning member 200 is moved with the front end 221 of the film 220 facing forward in the traveling direction, the front end 221 of the film 220 is prevented from being bent by being in contact with the restricting portion 104, and contributes to the discharge. It is possible to satisfactorily clean the part of the electrode 121 (part that is not in contact with the restricting portion 104).

According to the above, the following effects can be obtained in the present embodiment.
Since the film 220 is in contact with the grid electrode 121 at an angle, when the cleaning member 200 is moved, when the front end 221 of the film 220 faces forward in the movement direction (for example, the outward path during cleaning), the grid electrode 121 is used. The foreign matter fixed on the top can be scraped off with the tip 221. Further, when the cleaning member 200 is moved, when the leading end 221 of the film 220 faces rearward in the moving direction (for example, the return path during cleaning), the curved portion of the bent leading end 221 is on the grid electrode 121. Since cleaning is performed so that foreign matter (foreign matter that is not fixed) is stroked, resistance when the cleaning member 200 is moved can be reduced, and operability can be improved.

  Since the film 220 is supported by the support member 210 so as to bend when viewed from the direction connecting the front end 221 and the base end 222, the rigidity of the film 220 is improved with a simple configuration in which a reinforcing frame or the like is not provided. be able to. More specifically, in the configuration in which the film 220 is disposed obliquely with respect to the grid electrode 121 as in the present embodiment, the foreign matter fixed on the grid electrode 121 can be scraped off by being strongly rubbed with the tip 221. However, the film 220 may be bent due to the frictional resistance generated at that time. By being configured so that the film 220 is curved, it is possible to increase the rigidity of the film 220 during cleaning.

  By forming the notch 224 between the leading end 221 and both side ends 223 of the film 220, the leading end 221 and both side ends 223 of the film 220 are not affected by each other's bending, so the leading end 221 of the film 220 and both sides The end 223 can be brought into contact with the grid electrode 121 and each shield electrode 122 with high accuracy.

  Since the cleaning member 200 includes the plate-like sponge 230 that cleans the discharge wire 110 and the film 220 that cleans the counter electrode 120, the discharge wire 110 and the counter electrode 120 can be cleaned at the same time simply by moving the cleaning member 200. can do. Further, since the film 220 is sandwiched between the support member 210 and the plate-like sponge 230, the plate-like sponge 230 for cleaning the discharge wire 110 also serves as a member for preventing the film 220 from being detached from the support member 210. The number of parts can be reduced.

  When the cleaning member 200 is attached to the upper frame 100, the notch 224 of the film 220 abuts on the upper frame 100 and the slit 226 is opened, so that the discharge wire 110 is smoothly set in the hole 225 through the opened slit 226. Therefore, the cleaning member 200 can be easily attached.

  The open slit 226 can be closed by pushing the arm portions 212 of the support member 210 toward each other with the pair of tapered surfaces 103 of the upper frame 100, so that the leading end 221 of the film 220 can be satisfactorily used as the grid electrode 121. Can be in sliding contact.

In addition, this invention is not limited to the said embodiment, It can utilize with various forms so that it may illustrate below.
In the above-described embodiment, the notch 224 of the film 220 is configured to contact the engaging wall 102 of the upper frame 100. However, the present invention is not limited to this, and may be configured not to contact. Even in this case, when the engagement hole 227 of the film 220 is attached to the first protrusion 213 of the support member 210, the slit 226 can be opened. Therefore, the discharge wire 110 is inserted into the hole 225 through the opened slit 226. Can enter.

In the above-described embodiment, the film 220 is slidably contacted with the grid electrode 121 and each shield electrode 122. However, the present invention is not limited to this. For example, the film may be slidably contacted with only the grid electrode or only the shield electrode. Good.
In the said embodiment, although the film 220 made from PET was employ | adopted as a plate-shaped member, this invention is not limited to this, Other resin-made films may be sufficient and paper etc. may be sufficient.

In the embodiment, the notch 224 is formed as a V-shaped recess, but the present invention is not limited to this, and may be formed in a slit shape, for example.
In the above embodiment, the plate-like sponge 230 is used as the sliding contact member, but the present invention is not limited to this, and for example, a plate-like felt may be adopted.

In the above embodiment, the present invention is applied to the color printer 1. However, the present invention is not limited to this, and the present invention may be applied to other image forming apparatuses such as a copying machine and a multifunction machine.
In the above-described embodiment, the photosensitive drum 53 is employed as the photosensitive member. However, the present invention is not limited to this, and for example, a belt-shaped photosensitive member may be employed.

  As shown in FIGS. 11A and 11B, counter electrode sliding contact members 310 and 320 that are in sliding contact with the counter electrode may be provided at the tip of the plate-like member 300. As shown in FIG. 11A, the counter electrode sliding contact members 310 and 320 are attached to the plate member 300 in a U-shape so as to be turned from the upper surface of the plate member 300 through the tip to the lower surface. Alternatively, it may be attached to only one surface (surface on the counter electrode side) of the plate-like member 300 as shown in FIG.

  Here, as the plate-like member 300, for example, a PET film or the like can be adopted, and as the counter electrode sliding contact members 310 and 320, for example, urethane sponge (elastic member) or sandpaper (polishing member) can be adopted. . In addition, when urethane sponge is employ | adopted as the sliding contact members 310 and 320 for counter electrodes, since the sliding contact members 310 and 320 for counter electrodes closely_contact | adhere to a counter electrode, the wiping ability of a foreign material can further be improved. In addition, when sandpaper is employed as the slidable contact members 310 and 320 for the counter electrode, the ability to scrape the adhered foreign matter can be further increased, so that the firmly adhered foreign matter can be removed.

53 Photosensitive drum 54 Charger 100 Upper frame 102 Engaging rib 103 Tapered surface 110 Discharge wire 120 Counter electrode 121 Grid electrode 122 Shield electrode 200 Cleaning member 210 Support member 212 Arm portion 213 First projection 214 Second projection 215 Concavity 220 Film 221 Front end 222 Base end 223 Side end 224 Notch 225 Hole 226 Slit 227 Engagement hole 230 Plate-like sponge

Claims (9)

A discharge wire extending along a predetermined direction;
A counter electrode extending along the extending direction of the discharge wire and facing the discharge wire;
A frame that supports the discharge wire and the counter electrode;
A charger having
A cleaning member that cleans the counter electrode by moving in the extending direction while being in sliding contact with the counter electrode;
The cleaning member is
A plate-like member in contact with the counter electrode;
A support member for supporting the plate-like member,
The plate-like member has a distal end in contact with the counter electrode, and a proximal end located on the opposite side to the distal end,
The charger is characterized in that the plate member is supported obliquely with respect to the counter electrode so that the distal end and the proximal end are arranged at different positions in the extending direction. The plate-like member is configured to be deformable by bending,
The charger according to claim 1, wherein the plate-like member is curved as viewed from a direction connecting the distal end and the proximal end.   The charger according to claim 2, wherein the support member includes a concave portion that supports the plate-like member in a curved state. The counter electrode is
A grid electrode disposed between the discharge wire and a photosensitive member provided movably and capable of forming an electrostatic latent image on the surface;
It is composed of a pair of shield electrodes positioned so as to sandwich the discharge wire in the moving direction of the photoconductor,
The plate-like member has a pair of side ends positioned in a direction orthogonal to the direction connecting the distal end and the base end,
The said plate-shaped member is comprised so that it may curve, when the said front-end | tip contacts the said grid electrode and a pair of side end press-contacts to the said shield electrode. Item 4. The charger according to Item 3.   The charger according to claim 4, wherein a notch portion is formed between a front end and both side ends of the plate-like member. The cleaning member is
A sliding contact member supported by the support member and in sliding contact with the discharge wire in the extending direction;
The charger according to claim 5, wherein the plate-like member is disposed between the sliding contact member and the support member, and is sandwiched between the sliding contact member and the support member. In the plate member, a hole for passing the discharge wire is formed, and a slit is formed along the extending direction so as to come out from the hole to the tip of the plate member,
The support member is provided with two flexibly deformable arm portions that respectively support one and the other of the plate-like members separated by the slit,
The said slit member is comprised so that the said slit may open by the difference in the shape of the attachment part of the said arm part and the said plate member, when attaching the said plate member to the said supporting member. Charger.   8. The structure according to claim 7, wherein when the cleaning member is attached to the frame, the slits are further opened by a notch portion of the plate-like member coming into contact with the frame. Charger.   9. The charger according to claim 7, wherein the frame is formed with a tapered surface that pushes the arm portions toward each other.

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