JP5424110B2 - Rotating body grounding structure, image carrier unit, process unit, image forming apparatus, and rotating body grounding method - Google Patents

Description

  The present invention relates to an earth structure of a rotating body used in an image forming apparatus, an image carrier unit, a process unit, an image forming apparatus, and an earthing method of the rotating body using the earth structure of the rotating body.

  Conventionally, in an image forming apparatus such as a copying machine, a printer, a facsimile machine, or a complex machine of these, a rotating body such as a photosensitive drum and a shaft that rotatably supports the rotating body are electrically connected through a metal conductive member. There has been proposed a grounding structure for grounding a rotating body (see Patent Document 1).

A schematic configuration of the ground structure of the rotating body is shown in FIG.
In FIG. 31, reference numeral 100 denotes a photosensitive drum, and reference numeral 200 denotes a conductive shaft that supports the photosensitive drum. A flange 300 as a support member made of a non-conductive resin or the like is fitted to one end portion of the photosensitive drum 100, and the photosensitive drum 100 is rotatably supported with respect to the shaft 200 by the flange 300. Yes. Further, a metal leaf spring 400 as a conductive member is attached to the flange 300, and the leaf spring 400 is located at the inner peripheral surface of the photosensitive drum 100 and the outer periphery of the shaft 200 at locations indicated by reference numerals 400a and 400b in the drawing. Each surface is in contact. As described above, the photosensitive drum 100 and the shaft 200 are electrically connected by the plate spring 400, and the photosensitive drum 100 is grounded.

Further, although not a ground structure for connecting the rotating body and the shaft, an earth structure for grounding the rotating body using a conductive cloth or the like is disclosed (for example, see Patent Documents 2 and 3).
In the ground structure described in Patent Document 2, a conductive cloth is wound around a core made of foamed elastic resin to produce a gasket as a grounding means, and a roller shaft is pressed against the surface (conductive cloth) of the gasket. Grounded.
The ground structure disclosed in Patent Document 3 is grounded by attaching a conductive cloth to a grounding conductive plate and bringing the conductive cloth into contact with the rotation shaft of the transport roller.

  In the photosensitive unit shown in FIG. 31, when the photosensitive drum 100 is rotated, the leaf spring 400 slides with respect to the shaft 200. However, in this case, since the leaf spring 400 is made of metal, the contact portion 400b between the leaf spring 400 and the shaft 200 is worn on each other or any one of the members, and this causes abnormal noise. There's a problem. In addition, since the leaf spring 400 is made of metal, there is a possibility that poor conduction due to oxidation may occur. As a measure to prevent wear due to the sliding of the leaf spring, there is a method of applying a conductive lubricant to the contact portion between the leaf spring and the shaft, but the lubricant is gradually scraped off as the leaf spring slides. As a result, the lubrication effect decreases with time, and thus a fundamental solution cannot be achieved.

  In addition, as an example in which a metal conductive member is not used, there are techniques disclosed in Patent Documents 2 and 3 described above. However, since these are not grounded structures that connect the rotating body and the shaft, they can be rotated with respect to the shaft. It is difficult to apply to a grounding structure of a rotating body attached to.

  In view of such circumstances, the present invention prevents the wear and noise generated in the sliding portion of the conductive member, and can maintain a good continuity over a long period of time, and an image bearing It is intended to provide a body unit, a process unit, an image forming apparatus, and a rotating body grounding method.

According to the first aspect of the present invention, a cylindrical rotating body, a shaft inserted into the rotating body, and the rotating body supported between the rotating body and the shaft so as to be rotatable with respect to the shaft. And a flexible conductive member that is attached to the support member and is brought into contact with the inner peripheral surface of the rotating body and the outer peripheral surface of the shaft to conduct therethrough, and the support member is inserted into the rotating body. In a state where it is aligned with a possible position, the pressing member has a portion protruding to the outer peripheral side from the inner peripheral surface of the rotating body as viewed from the axial direction of the rotating body and elastically deformable in the radial direction of the rotating body. A member is provided on the support member, and the conductive member is pressed against the inner peripheral surface of the rotating body by the pressing member .

When the rotating body is rotated, the conductive member rotates while sliding with respect to the inner peripheral surface of the rotating body or the outer peripheral surface of the shaft. However, since the conductive member has flexibility, the conductive member with the rotating body or the shaft. There is almost no wear at the sliding part. Thereby, generation | occurrence | production of the noise in a sliding part can be suppressed or prevented highly. Further, since the conductive member can be pressed against the inner peripheral surface of the rotating body by the pressing member, a sufficient contact pressure of the conductive member with respect to the rotating body can be ensured, and stable conduction can be obtained.

According to a second aspect of the present invention, in the ground structure of the rotating body according to the first aspect, the portion of the pressing member that protrudes to the outer peripheral side from the inner peripheral surface of the rotating body is forward in the insertion direction to the rotating body. An inclined surface inclined in the inner diameter direction is provided.

When the support member is inserted into the rotating body, the inclined surface comes into contact with the opening end of the rotating body, so that the pressing member is not easily caught by the opening end of the rotating body, and the support member can be easily inserted into the rotating body.

According to a third aspect of the present invention, in the ground structure of the rotating body according to the first or second aspect , the conductive member is attached to the supporting member, and the supporting member is aligned with a position where the supporting member can be inserted into the rotating body. When viewed from the axial direction of the rotating body, the conductive member is located at a position where the first contact portion disposed on the outer peripheral side of the inner peripheral surface of the rotating body and the shaft in the rotating body are inserted. And a second contact portion disposed.

  Thus, by assembling the rotating body, the shaft, and the support member to which the conductive member is attached, the first contact portion of the conductive member is brought into contact with the inner peripheral surface of the rotary member, and the second contact portion of the conductive member is The rotating body and the shaft can be brought into conduction by being brought into contact with the outer peripheral surface of the shaft.

According to a fourth aspect of the present invention, in the ground structure of the rotating body according to the third aspect , the conductive member is attached to the front end of the supporting member in the inserting direction into the rotating body, and the front end of the supporting member on the outer peripheral surface is inserted in the inserting direction. On the side, at least a portion corresponding to the first contact portion of the conductive member is provided with a gap forming portion for forming a gap with the inner peripheral surface of the rotating member.

  In this case, when the support member is inserted into the rotating body with the conductive member attached to the support member, the first contact portion of the conductive member is formed between the gap forming portion and the inner peripheral surface of the rotating body. It is stored in the gap. For this reason, when the support member is inserted into the rotating body, the conductive member is not caught between the opening end of the rotating body and the support member. As a result, it is possible to prevent the conductive member from being damaged by being bitten and to easily insert the support member into the rotation. Moreover, by accommodating the first contact portion in the gap, a wide contact range between the first contact portion and the rotating body can be ensured, and conductivity can be improved.

According to a fifth aspect of the present invention, in the ground structure of the rotating body according to the third or fourth aspect , a plurality of the first contact portions are arranged in the circumferential direction of the rotating body.

  By arranging a plurality of first contact portions in the circumferential direction of the rotating body, the number of contact portions of the conductive member with respect to the rotating body can be increased, and more stable conduction can be ensured.

According to a sixth aspect of the present invention, in the ground structure of the rotating body according to the fifth aspect , the plurality of first contact portions are arranged at equal intervals in the circumferential direction of the rotating body.

  By arranging the plurality of first contact portions at equal intervals in the circumferential direction of the rotating body, the tensile force caused by the sliding contact between the inner peripheral surface of the rotating body and the first contact portion generated during assembly is reduced in the circumferential direction of the conductive member. Can be applied equally. As a result, the conductive member can contact the rotating body and the shaft at a predetermined position without being displaced.

The invention of claim 7, in which the grounding structure of the rotary body according to any one of claims 3 to 6, and the width of the inner diameter side of the first contact portion formed larger than the width of the outer diameter side is there.

  In this case, since the width on the inner diameter side of the first contact portion is formed to be large, the first contact portion is not easily tilted even if it contacts the rotating body, and the first contact portion rotates at the tip end portion (outer diameter side). Stable conduction can be ensured in a state where the contact pressure with the body is low.

The invention according to claim 8 is the ground structure of the rotating body according to any one of claims 3 to 7 , wherein the conductive member is formed of a rectangular sheet material, and a corner portion of the sheet material is the first contact. Part.

  When the corner portion of the sheet material is the first contact portion, since the width on the inner diameter side of the first contact portion is formed large, the first contact portion is unlikely to fall down even when contacting the rotating body. Stable conduction can be ensured in a state where the contact pressure with the rotating body is low at the tip end portion (outer diameter side) of the contact portion. In the case where the conductive member is formed of a rectangular sheet material, it is difficult to waste the material when the conductive member is cut out from the material, and the manufacturing cost can be reduced.

According to a ninth aspect of the present invention, in the ground structure of the rotating body according to any one of the third to eighth aspects, the second contact portion is formed by a notch through which the shaft can be inserted into the conductive member. It is composed.

  Thereby, the 2nd contact part can be constituted by simple processing which only forms a cut in a conductive member.

A tenth aspect of the present invention is the rotating body grounding structure according to any one of the third to eighth aspects, wherein the second contact portion includes a plurality of notches extending radially from a portion through which the shaft is inserted. It is what.

  In this case, the contact part of the electrically-conductive member with respect to a shaft can be increased, and more stable conduction | electrical_connection can be ensured.

An eleventh aspect of the present invention is the ground structure for a rotating body according to any one of the first to tenth aspects, wherein the support member is provided with a convex portion and the conductive member is inserted into the convex portion. , Slits or holes are provided.

  The conductive member can be positioned and held on the support member by inserting the convex portion provided on the support member into the slit, the slit, or the hole provided on the conductive member. Thereby, when inserting the support member to which the conductive member is attached into the rotating body, it is possible to prevent the conductive member from being displaced.

A twelfth aspect of the present invention is the ground structure of the rotating body according to any one of the first to eleventh aspects, wherein the support member is provided with a regulating portion that abuts against an outer edge of the conductive member to regulate radial movement. Is.

  When the support member with the conductive member attached is inserted into the rotating body, the restricting portion can abut against the outer edge of the conductive member to restrict radial movement, thereby preventing the conductive member from being displaced. it can.

According to a thirteenth aspect of the present invention, there is provided an image carrier constituted by a rotating body capable of carrying an image on a surface thereof, a shaft inserted into the image carrier, and disposed between the image carrier and the shaft. The rotating body according to any one of claims 1 to 12 , wherein an earth structure of the image carrier is provided in an image carrier unit including a support member that rotatably supports the image carrier with respect to the shaft. The earth structure is used.

When the ground structure of the rotating body according to any one of claims 1 to 12 is used for the ground structure of the image carrier, the above-described effect by these ground structures can be obtained.

According to a fourteenth aspect of the present invention, there is provided a process unit that integrally includes at least one of a charging unit, a developing unit, and a cleaning unit and an image carrier, and is configured to be detachable from the image forming apparatus main body. A process unit comprising the image carrier unit according to claim 13 .

Since the process unit includes the image carrier unit according to the thirteenth aspect , the above-described effect can be obtained by the ground structure provided in the image carrier unit.

A fifteenth aspect of the invention is an image forming apparatus including the process unit according to the fourteenth aspect .

Since the image forming apparatus includes the process unit according to the fourteenth aspect , the above-described effect can be obtained by the ground structure included in the process unit.

A sixteenth aspect of the invention is an image forming apparatus provided with the grounding structure of the rotating body according to any one of the first to twelfth aspects.

Since the image forming apparatus includes the rotating body grounding structure according to any one of the first to twelfth aspects, the above-described effects of these grounding structures can be obtained.

According to a seventeenth aspect of the present invention, in the method for grounding a rotating body, wherein the rotating member is rotatably supported with respect to the shaft by a supporting member disposed between the cylindrical rotating body and the shaft, the supporting member includes: The rotating member has a portion protruding to the outer peripheral side from the inner peripheral surface of the rotating body when viewed from the axial direction of the rotating body in a state where the support member is aligned at a position where the supporting member can be inserted into the rotating body. A pressing member that can be elastically deformed in a radial direction, and a flexible conductive member is attached to the support member, and the conductive member is assembled by assembling the support member, the rotating body, and the shaft. the inner peripheral surface of the rotary body and causes contact with the outer peripheral surface of the shaft, is held in a pressed state on the inner peripheral surface of the rotary member wherein the conductive member by the pressing member, wherein said rotating body Sha A method for conducting the door.

When the rotating body is rotated, the conductive member rotates while sliding with respect to the inner peripheral surface of the rotating body or the outer peripheral surface of the shaft. However, since the conductive member has flexibility, the conductive member with the rotating body or the shaft. There is almost no wear at the sliding part. Thereby, generation | occurrence | production of the noise in a sliding part can be suppressed or prevented highly. Further, since the conductive member can be pressed against the inner peripheral surface of the rotating body by the pressing member, a sufficient contact pressure of the conductive member with respect to the rotating body can be ensured, and stable conduction can be obtained.

  According to the present invention, since wear hardly occurs in the sliding portion of the conductive member with the rotating body or the shaft, generation of abnormal noise in the sliding portion can be highly suppressed or prevented. In addition, according to the configuration of the present invention, it is not necessary to apply a conductive lubricant for the purpose of reducing sliding resistance to the contact portion between the conductive member and the shaft or the rotating body. Can be reduced. In addition, since the conductive member does not oxidize, stable conduction can be ensured over a long period of time.

1 is a schematic configuration diagram illustrating an embodiment of an image forming apparatus according to the present invention. It is a schematic block diagram of the process unit of this invention. 1 is an external perspective view of an image carrier unit according to the present embodiment. FIG. 3 is a cross-sectional view of peripheral parts of the image carrier unit cut in the longitudinal direction of the image carrier unit. It is sectional drawing of the structure which concerns on a 1st reference example . It is an exploded sectional view of the composition concerning the 1st reference example . It is a disassembled perspective view of the structure which concerns on a said 1st reference example . It is a top view of the electrically-conductive member which concerns on a said 1st reference example . It is a disassembled perspective view of the structure which concerns on a 2nd reference example . It is a top view of the electrically-conductive member which concerns on a 2nd reference example . It is a figure which shows how to cut out the electrically-conductive member which concerns on a 2nd reference example . It is sectional drawing of the structure which concerns on 1st Embodiment of this invention. FIG. 3 is an exploded cross-sectional view of the configuration according to the first embodiment. It is a disassembled perspective view of the structure which concerns on the said 1st Embodiment. It is a principal part enlarged view of the supporting member which concerns on the said 1st Embodiment. It is a figure which shows the modification of the supporting member which concerns on the said 1st Embodiment. It is a figure which shows the modification of the electrically-conductive member which concerns on this invention. It is a figure which shows the other modification of the electrically-conductive member which concerns on this invention. It is sectional drawing of the structure which concerns on 2nd Embodiment of this invention. It is an exploded sectional view of the composition concerning the 2nd embodiment. It is a disassembled perspective view of the structure which concerns on the said 2nd Embodiment. It is sectional drawing of the structure which concerns on 3rd Embodiment of this invention. It is an exploded sectional view of the composition concerning the 3rd embodiment. It is a perspective view of the support member which attached the cyclic | annular elastic body which concerns on the said 3rd Embodiment. It is a figure which shows the modification of the said annular elastic body. It is a figure which shows the modification of the said supporting member. It is a figure which shows the other modification of the electrically-conductive member which concerns on this invention. It is a figure which shows the modification of the notch | incision formed in the electrically-conductive member which concerns on this invention. It is a figure which shows the state which penetrated the shaft in the notch | incision shown in FIG.28 (e). It is sectional drawing which shows embodiment which applied the structure of this invention to the earth structure of the drive roller. It is a schematic sectional drawing of the earth structure of the conventional rotary body.

  Hereinafter, the present invention will be described with reference to the accompanying drawings. In the drawings for explaining the present invention, components such as members and components having the same function or shape are denoted by the same reference numerals as much as possible, and once described, the description will be given. Omitted.

  FIG. 1 is a schematic configuration diagram of a color image forming apparatus according to the present invention. The image forming apparatus illustrated in FIG. 1 includes four process units 1Bk, 1Y, 1M, and 1C configured to be detachable from the image forming apparatus main body 25. Each process unit 1Bk, 1Y, 1M, 1C has the same configuration except that it contains toners of different colors of black, yellow, magenta, and cyan corresponding to the color separation components of the color image.

FIG. 2 is a schematic configuration diagram of each process unit.
As shown in FIG. 2, the process unit 1 includes a photosensitive drum 2 as an image carrier, a charging roller 3 as a charging unit that charges the surface of the photosensitive drum 2, and toner on the surface of the photosensitive drum 2. A developing device 4 as a developing means to be supplied and a cleaning blade 5 as a cleaning means for cleaning the surface of the photosensitive drum 2 are integrally provided. In FIG. 2, alphabets (Bk, Y, M, C,) of symbols representing color identification are omitted.

  In FIG. 1, an exposure device 6 as an exposure means for exposing the surface of the photosensitive drum 2 is disposed above each process unit 1Bk, 1Y, 1M, 1C. A transfer device 7 is disposed below each process unit 1Bk, 1Y, 1M, 1C. The transfer device 7 has an intermediate transfer belt 8 constituted by an endless belt as a transfer body. The intermediate transfer belt 8 is stretched around the driving roller 9 and the driven roller 10 and is configured to be rotatable (circular running) in the direction of the arrow in the figure.

  Four primary transfer rollers 11 as primary transfer means are disposed at positions facing the four photosensitive drums 2. Each primary transfer roller 11 presses the inner peripheral surface of the intermediate transfer belt 8 at each position, and a primary transfer nip is formed at a location where the pressed portion of the intermediate transfer belt 8 and each photosensitive drum 2 come into contact with each other. Has been. A secondary transfer roller 12 as a secondary transfer unit is disposed at a position facing the drive roller 9. The secondary transfer roller 12 presses the outer peripheral surface of the intermediate transfer belt 8, and a secondary transfer nip is formed at a location where the secondary transfer roller 12 and the intermediate transfer belt 8 are in contact with each other.

  A belt cleaning device 13 for cleaning the surface of the intermediate transfer belt 8 is disposed on the outer peripheral surface on the right end side of the intermediate transfer belt 8 in the drawing. A waste toner transfer hose (not shown) extending from the belt cleaning device 13 is connected to an entrance of a waste toner container 14 disposed below the transfer device 7.

  A lower part of the image forming apparatus main body 25 is provided with a paper feed tray 15 that stores recording paper P as a recording medium, a paper feed roller 16 that carries the recording paper P out of the paper feed tray 15, and the like. On the other hand, a pair of paper discharge rollers 17 for discharging recording paper to the outside and a paper discharge tray 18 for stocking the discharged recording medium are disposed on the upper portion of the image forming apparatus main body 25. .

  Further, a conveyance path R for guiding recording paper from the lower paper feed tray 15 to the upper paper discharge tray 18 is formed in the image forming apparatus main body 60. A pair of registration rollers 19 is disposed on the conveyance path R in the middle from the paper feed roller 16 to the secondary transfer roller 12. In addition, a fixing device 20 for fixing an image on the recording paper is provided on the way from the secondary transfer roller 12 to the paper discharge roller 17. The fixing device 20 includes a fixing roller 21 as a fixing member that is heated by a heating source, a pressure roller 22 as a pressure member that pressurizes the fixing roller 21, and the like. A fixing nip is formed at a location where the fixing roller 21 and the pressure roller 22 are in pressure contact with each other.

The basic operation of the image forming apparatus will be described below with reference to FIG.
When the image forming operation is started, the photosensitive drums 2 of the process units 1Bk, 1Y, 1M, and 1C are rotationally driven clockwise by a driving device (not shown), and the surface of each photosensitive drum 2 is charged with the charging roller 3. Are uniformly charged to a predetermined polarity. The surface of each charged photosensitive drum 2 is irradiated with laser light L (see FIG. 2) from the exposure device 6, and an electrostatic latent image is formed on the surface of each photosensitive drum 2. At this time, the image information to be exposed to each photosensitive drum 2 is single-color image information obtained by separating a desired full-color image into color information of yellow, cyan, magenta, and black. Thus, the electrostatic latent image is visualized as a toner image (developer image) by supplying toner to the electrostatic latent image formed on the photosensitive drum 2 by each developing device 4. .

  By driving the drive roller 9 counterclockwise in the figure, the intermediate transfer belt 8 is driven to travel in the direction indicated by the arrow in the figure. Further, a constant voltage or a constant current controlled voltage having a polarity opposite to the toner charging polarity is applied to each primary transfer roller 11. Thereby, a transfer electric field is formed at the primary transfer nip between each primary transfer roller 11 and each photosensitive drum 2. Then, the toner images of the respective colors formed on the photosensitive drums 2 of the process units 1Bk, 1Y, 1M, and 1C are sequentially superimposed and transferred onto the intermediate transfer belt 8 by the transfer electric field formed in the primary transfer nip. Is done. Thus, the intermediate transfer belt 8 carries a full-color toner image on its surface.

  Residual toner adhering to the surface of each photosensitive drum 2 after the toner image is transferred is removed by the cleaning blade 5, and then the surface is subjected to a neutralizing action by a neutralizing device (not shown) so that the surface potential is reduced. Initialized to prepare for the next image formation.

  Further, in the lower part of the image forming apparatus, the recording paper P accommodated in the paper feed tray 15 is sent out to the transport path R by rotating the paper feed roller 16. The recording paper P sent to the transport path R is timed by the registration roller 19 and sent to the secondary transfer nip between the secondary transfer roller 12 and the driving roller 9 facing it. At this time, a transfer voltage having a polarity opposite to the toner charging polarity of the toner image on the intermediate transfer belt 8 is applied to the secondary transfer roller 12, and a transfer electric field is formed in the secondary transfer nip. Then, the toner images on the intermediate transfer belt 8 are collectively transferred onto the recording paper P by the transfer electric field formed in the secondary transfer nip. The recording paper P to which the toner image has been transferred is conveyed to the fixing unit 20, and the recording paper P is heated and pressed by the fixing roller 21 and the pressure roller 22 to fix the toner image. Then, the recording paper P on which the toner image is fixed is discharged to a paper discharge tray 18 by a discharge roller 17. Further, the toner remaining on the intermediate transfer belt 8 after the transfer is removed by the belt cleaning device 13, and the removed toner is conveyed to the waste toner container 14 and collected.

  The above description is an image forming operation when a full-color image is formed on a recording sheet. A single-color image is formed using any one of the four process units 1Bk, 1Y, 1M, and 1C. Two or three process units may be used to form a two or three color image.

FIG. 3 is an external perspective view of the image carrier unit 24 according to the present embodiment. FIG. 4 is a cross-sectional view of peripheral parts of the image carrier unit 24 cut in the longitudinal direction (axial direction) of the image carrier unit 24.
As shown in FIGS. 3 and 4, the image carrier unit 24 includes a cylindrical photosensitive drum 2, two supporting members 31 and 32 inserted into both ends of the photosensitive drum 2, and each supporting member. It is comprised by the shaft 40 etc. which were provided so that the center part of 31 and 32 might be penetrated. The photosensitive drum 2 is rotatably supported with respect to the shaft 40 via these support members 31 and 32.

  Specifically, each of the support members 31 and 32 is configured by a cylindrical member having holes 31 a and 32 a for inserting the shaft 40. In the present embodiment, the support members 31 and 32 are attached to the photosensitive drum 2 by press fitting. The support members 31 and 32 have contact portions 31b and 32b protruding in the outer diameter direction, respectively, and when the support members 31 and 32 are press-fitted into the photosensitive drum 2, the contact portions are provided. Each support member 31 and 32 is positioned at a predetermined position by abutting 31b and 32b on the opening end of the photosensitive drum 2.

  In FIG. 3 or FIG. 4, a gear portion 32 c composed of a plurality of teeth arranged in the circumferential direction is provided on the outer peripheral surface of the portion of the left support member 32 exposed from the photosensitive drum 2. The gear portion 32c meshes with a driving force transmission member such as a gear train of a driving device (not shown), and the photosensitive drum 2 is connected to the shaft 40 by the rotation drive of the driving device being transmitted through the gear portion 32c. Rotate with respect to.

  The shaft 40 is supported by the frame 29 of the process unit at both ends thereof. Further, the shaft 40 is attached to the frame 29 so as not to rotate by a rotation preventing member 33 such as a retaining ring, and is prevented from coming off to the left in the drawing. The shaft 40 is completely prevented from coming off in the axial direction by a separate member (not shown) at the end opposite to the end where the rotation preventing member 33 is disposed.

  As described above, the photosensitive drum 2 is repeatedly charged and discharged every time image formation is performed. In order to remove static electricity accumulated in the charged photosensitive drum 2, the photosensitive drum 2 is provided with a ground structure. In this embodiment, the shaft 40 is made of metal such as conductive special steel and has conductivity, but the two support members 31 and 32 are made of non-conductive resin or the like. For this reason, in this embodiment, as shown in FIG. 4, the conductive member 50 is attached to the right support member 31, and the photosensitive drum 2 and the shaft 40 are electrically connected via the conductive member 50.

It will be described below A over the scan structure.
First, the structure which concerns on a 1st reference example is demonstrated based on FIGS.
5 is a cross-sectional view of the periphery of the end portion of the photosensitive drum 2 where the conductive member 50 is disposed, and FIG. 6 is an exploded view showing a state before the photosensitive drum 2, the support member 31, and the shaft 40 shown in FIG. It is a perspective view. FIG. 7 is an exploded perspective view showing a state before the support member 31 and the conductive member 50 are attached, and FIG. 8 is a plan view of the conductive member 50.

  As shown in FIG. 5, the photosensitive drum 2 includes a cylindrical conductive substrate 2a and a photosensitive layer 2b disposed on the outer peripheral surface of the conductive substrate 2a. The conductive member 50 has a first contact portion A that contacts the conductive substrate 2 a (inner peripheral surface) of the photosensitive drum 2 and a second contact portion B that contacts the outer peripheral surface of the shaft 40. . The conductive member 50 is composed of a sheet-like member having conductivity and flexibility. For example, the conductive member 50 is made of a cloth material in which at least one of polyethylene terephthalate fiber, nylon fiber, and polyester fiber, and nickel and copper are woven, and has appropriate lubricity as well as electrical conductivity.

In FIG. 5, the support member 31 is inserted into the photosensitive drum 2 from the right side to the left side of the drawing, and a conductive member 50 is attached to the front end 31 c in the insertion direction of the support member 31. Specifically, as shown in FIG. 7, the front end 31 c (end surface) in the insertion direction of the support member 31 is provided with a plurality of convex portions 31 d, and each convex portion 31 d is formed in the conductive member 50 as a single character type cut 50 a. The conductive member 50 can be attached to the support member 31 by being inserted into the support member 31. In this reference example , the convex portion 31d and the cut 50a are provided in two symmetrical positions with respect to the central portion. Moreover, you may form a slit, a hole, etc. with an opening width instead of the notch 50a.

  As shown in FIG. 7, a cross-shaped or radial cut 50 b is formed in the central portion of the conductive member 50. The cross-shaped notch 50b is disposed at a position corresponding to the shaft insertion hole 31a in a state where the conductive member 50 is disposed at the mounting position with respect to the support member 31. That is, the cross-shaped notch 50 b is formed at a position where the shaft 40 is inserted into the support member 31. By forming the cross-shaped notches 50b, four triangular pieces 50d that can be bent independently are formed in the central portion of the conductive member 50. These triangular pieces 50d function as the second contact portion B that bends and contacts the outer peripheral surface of the shaft 40 when the shaft 40 is inserted into the cut 50b (see FIG. 5).

  Moreover, as shown in FIG. 7 or FIG. 8, the conductive member 50 has two rectangular protruding piece portions 50c protruding from the peripheral edge thereof. Each projecting piece 50c is disposed on the opposite edge with the central portion in between. As shown in FIG. 6, the conductive member 50 is attached to the support member 31, and the support member 31 is positioned at a position where the support member 31 can be inserted into the photoconductor drum 2, as viewed from the axial direction of the photoconductor drum 2 ( The protrusions 50c are disposed on the outer peripheral side with respect to the inner peripheral surface 2c of the photosensitive drum 2 as shown in FIG. That is, the projecting piece 50c functions as the first contact portion A that comes into contact with the inner peripheral surface 2c when inserted into the photosensitive drum 2 (see FIG. 5).

As shown in FIG. 7, the outer peripheral surface of the support member 31 has the largest outer diameter contact portion 31b for positioning, and the outer peripheral surface is smaller than the contact portion 31b and has an inner peripheral surface of the photosensitive drum 2. And a fitting portion 31f that fits, and a gap forming portion 31e having an outer diameter smaller than that of the fitting portion 31f. The gap forming portion 31e is formed in a continuous manner with the insertion direction front end 31c. Accordingly, in this reference example , a gap S is formed between the gap forming portion 31e and the inner peripheral surface 2c of the photosensitive drum 2 with the support member 31 inserted into the photosensitive drum 2 (see FIG. 5). It has come to be.

Hereinafter, a method for assembling the photosensitive drum 2, the conductive member 50, the support member 31, and the shaft 40 will be described.
First, in FIG. 7, each convex portion 31 d of the support member 31 is inserted into each single-character notch 50 a of the conductive member 50, and the conductive member 50 is positioned and attached to the support member 31. Next, as shown in FIG. 6, the support member 31 to which the conductive member 50 is attached is inserted into the photosensitive drum 2. At this time, the protruding piece portion 50 c of the conductive member 50 is bent in contact with the opening end of the photosensitive drum 2 and is inserted into the photosensitive drum 2. The projecting piece 50c is pushed into the back side (axial center side) of the photosensitive drum 2 while being in sliding contact with the inner peripheral surface of the photosensitive drum 2. At that time, a tensile force is applied by friction to the projecting piece portion 50c that is in sliding contact with the inner peripheral surface of the photosensitive drum 2, but the conductive member 50 is held by the convex portion 31d of the support member 31, so that the positional shift is caused. Is prevented. As shown in FIG. 5, the insertion of the support member 31 is completed when the contact portion 31 b of the support member 31 contacts the opening end of the photosensitive drum 2. In the inserted state of the support member 31 shown in FIG. 5, the protruding piece portion 50 c (first contact portion A) is formed between the gap forming portion 31 e of the support member 31 and the inner peripheral surface 2 c of the photosensitive drum 2. It is maintained in a state of being in contact with the inner peripheral surface 2c of the photosensitive drum 2 while being accommodated in the gap S.

  After completing the insertion of the support member 31, the shaft 40 is inserted into the hole 31a of the support member 31 from the right side to the left side in FIG. When the tip of the shaft 40 reaches the position of the conductive member 50, the shaft 40 penetrates so as to spread the cross-shaped notch 50 b formed at the center of the conductive member 50. At this time, each triangular piece 50d (second contact portion B) formed by the cross-shaped notch 50b bends and contacts the outer peripheral surface of the shaft 40. The triangular pieces 50d are maintained in contact with the outer peripheral surface of the shaft 40 in a state where the insertion of the shaft 40 is completed. In this way, the assembly of each member is completed, and as a result, the photosensitive drum 2 and the shaft 40 are electrically connected via the conductive member 50.

In the first reference example , when the support member 31 is inserted into the photosensitive drum 2, the protruding piece portion 50 c of the conductive member 50 has a gap between the gap forming portion 31 e and the inner peripheral surface 2 c of the photosensitive drum 2. Therefore, the conductive member 50 is not caught between the open end of the photosensitive drum 2 and the outer peripheral surface of the support member 31. For this reason, it is possible to prevent the conductive member 50 from being damaged due to being bitten and to easily insert the support member 31 into the photosensitive drum 2. In addition, by accommodating the projecting piece portion 50c in the gap S, a wide contact range between the projecting piece portion 50c and the photosensitive drum 2 can be secured, and conduction can be improved. . In this reference example , the gap forming part 31e is formed over the entire circumference of the outer periphery of the support member 31, but the gap forming part 31e may be at least at a position corresponding to the protruding piece part 50c.

  Note that the order in which the support member 31 and the shaft 40 are assembled to the photosensitive drum 2 is not limited to the order described above. If the state after assembly of each member is the state shown in FIG. 5, the assembly order can be changed as appropriate. For example, the support member 31 may be inserted into the photosensitive drum 2 after the shaft 40 is inserted through the support member 31.

9 to 11 show a configuration according to the second reference example .
FIG. 9 is an exploded perspective view showing a state before the support member 31 and the conductive member 50 are attached, and FIG. 10 is a plan view of the conductive member 50. FIG. 11 is a diagram showing how to cut the conductive member 50.

In the second reference example , the configurations of the conductive member 50 and the support member 31 are different from those of the first reference example . First, the configuration of the conductive member 50 will be described.
As shown in FIGS. 9 and 10, the conductive member 50 according to the second reference example has a square outer shape. Of the two large and small one-dot chain circles shown in FIG. 10, the larger one-dot chain line circle is aligned with the position where the conductive member 50 is inserted into the photosensitive drum 2, and the photosensitive drum 2 viewed from the axial direction. The position of the inner peripheral surface 2c is shown. As shown in FIG. 10, the four corners 50 i of the conductive member 50 are disposed on the outer peripheral side of the inner peripheral surface 2 c of the photosensitive drum 2. That is, in this reference example , the four corner portions 50i function as the first contact portion A that comes into contact with the inner peripheral surface 2c when inserted into the photosensitive drum 2.

  In FIG. 10, the smaller one-dot chain line circle indicates the insertion position of the shaft 40. As in the first embodiment, a cross-shaped notch 50b is formed at a portion of the conductive member 50 corresponding to the insertion position of the shaft 40, and can be bent independently. A piece 50d (second contact portion B) is formed.

Next, the configuration of the support member 31 according to the second reference example will be described.
As shown in FIG. 9, four convex regulating portions 31 g are provided on the periphery of the front end 31 c (end surface) in the insertion direction of the support member 31. Each regulating portion 31g abuts on the outer edge of the conductive member 50 in a state where the conductive member 50 is attached to the support member 31, and regulates the movement in the radial direction. Further, in the state where the conductive member 50 is attached to the support member 31, a planar gap forming portion 31 e is formed on the outer peripheral surface of the support member 31 corresponding to the four corners 50 i of the conductive member 50. Thus, when the support member 31 is inserted into the photosensitive drum 2, each corner 50 i of the conductive member 50 can be inserted into a gap formed between the gap forming portion 31 e and the photosensitive drum 2. . Further, the assembly of each member in the second reference example can be performed in the same manner as in the first reference example, and thus the description thereof is omitted.

As described above, in the second reference example according to the present invention, since the support member 31 is provided with the plurality of restricting portions 31g, when the support member 31 to which the conductive member 50 is attached is inserted into the photosensitive drum 2. The conductive member 50 can be prevented from being displaced in the radial direction. In the second embodiment, since the conductive member 50 is formed in a square shape, as shown in FIG. 11, when the conductive member 50 is cut from the sheet material 49 and manufactured, the sheet material 49 as a raw material is wasted. Is less likely to occur. Thereby, the manufacturing cost can be reduced. In this reference example , since the triangular corner portion 50i is the first contact portion A, the inner diameter side width of the first contact portion A is larger than the outer diameter side width. For this reason, even if the first contact portion A comes into contact with the photosensitive drum 2, the first contact portion A is less likely to fall down, and is stable in a state where the contact pressure with the photosensitive drum 2 is low at the tip end portion (outer diameter side) of the first contact portion A. Can be ensured.

12 to 15 show a configuration according to the first embodiment of the present invention.
12 is a cross-sectional view of the periphery of the end of the photosensitive drum 2 where the conductive member 50 is disposed, and FIG. 13 is an exploded view showing the state before the photosensitive drum 2, the support member 31, and the shaft 40 shown in FIG. It is sectional drawing. FIG. 14 is an exploded perspective view showing a state before the support member 31 and the conductive member 50 are attached, and FIG. 15 is an enlarged view of a main part of the support member 31.

As shown in FIGS. 12 to 14, the support member 31 according to the first embodiment includes a pair of elastic arms 31 h that are elastically deformable in the radial direction as pressing members that press the conductive member 50. Other than that, each member is basically configured in the same manner as the first reference example shown in FIGS. The tip of each elastic arm 31h is positioned on the outer peripheral surface side of the inner peripheral surface 2c of the photosensitive drum 2 in a state where the support member 31 is aligned with the position where the support member 31 is inserted into the photosensitive drum 2 (see FIG. 13). Protruding. In this embodiment, each elastic arm 31h is integrally provided so as to protrude or extend forward in the insertion direction from the step surface connecting the gap forming portion 31e and the fitting portion 31f of the support member 31. .

  As shown in FIG. 14, each elastic arm 31 h and the protruding piece of the conductive member 50 in a state where the conductive member 50 is disposed at the mounting position with respect to the support member 31 (the position of the conductive member 50 indicated by a dotted line in the same figure). The parts 50c correspond to each other. Note that the number of elastic arms 31h may be determined according to the number of projecting piece portions 50c provided on the conductive member 50, and thus is not limited to two as in this embodiment.

  FIG. 15A is an enlarged view of the elastic arm 31h. Further, in the figure, the alternate long and short dash line indicates the position of the inner peripheral surface 2 c of the photosensitive drum 2 in a state where the support member 31 is aligned with the position where the support member 31 is inserted into the photosensitive drum 2.

  As shown in FIG. 15A, in this embodiment, a flat inclined surface 310 is formed on a portion of the elastic arm 31h that protrudes to the outer peripheral side at least from the inner peripheral surface 2c of the photosensitive drum 2. . The inclined surface 310 is inclined in the inner diameter direction toward the front in the insertion direction (left direction in FIG. 15A). Further, as shown in FIG. 15B, the inclined surface 310 may be formed in a curved surface shape.

As shown in FIG. 13, when the conductive member 50 is attached to the support member 31 and the support member 31 is inserted into the photosensitive drum 2, the protruding piece 50 c and the elastic arm 31 h of the conductive member 50 are connected to the photosensitive drum 2. Contact the open end. Further, when the support member 31 is pushed into the photosensitive drum 2, the elastic arm 31h is elastically deformed in the inner diameter direction and is inserted into the photosensitive drum 2 together with the protruding piece portion 50c. Then, as shown in FIG. 12, when the insertion of the support member 31 is completed, each projecting piece 50c is held in a state of being pressed against the inner peripheral surface 2c of the photosensitive drum 2 by the elastic arm 31h. Further, in this state, each protruding piece 50 c is accommodated in a gap S formed between the gap forming portion 31 e of the support member 31 and the inner peripheral surface 2 c of the photosensitive drum 2. In the third embodiment, the attachment of the conductive member 50 to the support member 31 and the assembly of the support member 31 and the shaft 40 can be performed in the same manner as in the first reference example, and thus the description thereof is omitted. To do.

As described above, in the first embodiment according to the present invention, the protruding piece 50c of the conductive member 50 can be pressed toward the inner peripheral surface 2c of the photosensitive drum 2 by the elastic arm 31h. The contact pressure of the projecting piece 50c with respect to can be sufficiently secured. This makes it possible to obtain stable conduction between the conductive member 50 and the photosensitive drum 2. In this embodiment, since the inclined surface 310 is formed on the elastic arm 31h, the elastic arm 31h is not easily caught on the opening end of the photosensitive drum 2 when the support member 31 is inserted into the photosensitive drum 2. It becomes easy to insert the elastic arm 31 h into the photosensitive drum 2.

In the ground structure of the present invention that does not have the elastic arm 31h (see, for example, FIG. 7 and FIG. 9), the photosensitive member increases as the radial width of the gap S formed by the gap forming portion 31e decreases. It becomes easy to ensure the contact pressure of the protruding piece 50c with respect to the inner peripheral surface 2c of the drum 2. However, if the radial width of the gap S is made too small, it becomes difficult to insert the projecting piece 50c into the gap S, so that the dimension management of the gap S is important. On the other hand, in the first embodiment, the elastic arm 31h can ensure the contact pressure of the projecting piece 50c, so that the contact pressure does not depend on the size of the gap S, and the gap S There is an advantage that the dimensional management is easy.

FIG. 16 shows a modification of the support member 31 according to the first embodiment.
In the modification shown in FIG. 16, the elastic arm 31 h is configured as a member separate from the support member 31. In this modification, a recess 311 is formed in the fitting surface 31f of the support member 31, and the elastic arm 31h is fitted into the recess 311 and the elastic arm 31h is fixed by a fixing means (not shown). As described above, when the elastic arm 31h is configured as a member separate from the support member 31, the material of the elastic arm 31h can be selected from a material different from the material of the support member 31. It is possible to adjust the pressing force of the elastic arm 31h against the protruding piece 50c.

FIGS. 17 and 18 are diagrams showing modifications of the conductive member 50.
As shown in FIG. 17A, when the conductive member 50 is formed in a substantially S shape, the pair of projecting piece portions 50c of the conductive member 50 are attached to correspond to the elastic arm 31h. Further, as shown in FIG. 18A, when the conductive member 50 is formed in a diamond shape, a pair of corner portions 50i facing the conductive member 50 may be attached to correspond to the elastic arm 31h. Further, when the conductive member 50 is formed in the substantially S shape or the rhombus as described above, when the conductive member 50 is cut from the sheet material 49 as shown in FIG. 17B or FIG. In addition, the sheet material 49 is hardly wasted, and the manufacturing cost can be reduced.

19 to 21 show a configuration according to the second embodiment of the present invention.
19 is a cross-sectional view of the periphery of the end of the photosensitive drum 2 where the conductive member 50 is disposed, and FIG. 20 is an exploded view showing a state before the photosensitive drum 2, the support member 31, and the shaft 40 shown in FIG. It is sectional drawing. FIG. 21 is an exploded perspective view showing a state before the support member 31 and the conductive member 50 are attached.

As shown in FIGS. 19 to 21, the support member 31 according to the second embodiment includes a restricting portion 31 g (see FIG. 9 and the like) in the second reference example, and an elastic arm 31 h (FIG. 14) in the first embodiment. Etc.). However, restricting portion 31g and the elastic arm 31h in the second embodiment is slightly different configuration from that of the second reference example and the first embodiment. Specifically, as shown in FIG. 21, only two restricting portions 31g are provided corresponding to the shape of the conductive member 50 to be attached. The elastic arm 31h is formed so as to extend toward the rear end in the insertion direction, and is inclined in the inner diameter direction toward the front in the insertion direction as a whole. In addition, since the effect | action and effect by the control part 31g and the elastic arm 31h in 2nd Embodiment are the same as the effect | action and effect demonstrated in the said 2nd reference example and 1st Embodiment, description is abbreviate | omitted.

22 to 26 show a configuration according to the third embodiment of the present invention.
22 is a cross-sectional view of the periphery of the end portion of the photosensitive drum 2 where the conductive member 50 is disposed, and FIG. 23 is an exploded view showing a state before the photosensitive drum 2, the support member 31, and the shaft 40 shown in FIG. It is a perspective view. 24 is a perspective view of the support member 31 to which the annular elastic body 31i is attached, FIG. 25 is a view showing a modification of the annular elastic body 31i, and FIG. 26 is a view showing a modification of the support member 31. .

As shown in FIGS. 22 to 24, in the gap forming portion 31e of the support member 31 according to the third embodiment, an annular elastic body 31i formed of rubber or sponge is used as a pressing member that presses the conductive member 50. It is installed. As shown in FIG. 23, in a state where the support member 31 on which the annular elastic body 31 i is mounted is aligned with the position where it is inserted into the photosensitive drum 2, the outer peripheral surface of the annular elastic body 31 i is the surface of the photosensitive drum 2. It protrudes to the outer peripheral surface side from the inner peripheral surface 2c.

As shown in FIG. 23, when the conductive member 50 is attached to the support member 31 and the support member 31 is inserted into the photosensitive drum 2, the annular elastic body 31 i protrudes from the projecting portion 50 c with respect to the opening end of the photosensitive drum 2. It contacts through. Further, when the support member 31 is pushed into the photosensitive drum 2, the annular elastic body 31 i is compressed and elastically deformed in the inner diameter direction and inserted into the photosensitive drum 2. As shown in FIG. 22, in a state where the insertion of the support member 31 is completed, each projecting piece 50 c is formed in the gap S formed between the gap forming portion 31 e and the inner peripheral surface 2 c of the photosensitive drum 2. While being accommodated, each projecting piece 50c is held in a state of being pressed against the inner peripheral surface 2c of the photosensitive drum 2 by the compressed annular elastic body 31i. In the third embodiment, the attachment of the conductive member 50 to the support member 31 and the assembly of the support member 31 and the shaft 40 can be performed in the same manner as described in the first reference example . .

As described above, in the third embodiment, the projecting piece 50c of the conductive member 50 can be pressed toward the inner peripheral surface 2c of the photosensitive drum 2 by the annular elastic body 31i. The contact pressure of the portion 50c can be sufficiently secured, and stable conduction can be obtained. In addition, since the annular elastic body 31i is provided, the contact pressure of the projecting piece 50c does not depend on the size of the gap S between the gap forming portion 31e and the photosensitive drum 2, so that the size management of the gap S is easy. It becomes.

  Further, in this embodiment, the outer peripheral surface of the annular elastic body 31i is formed in a circular shape as shown in FIG. 24A, and the conductive member 50 is attached to the photosensitive drum 2 over the entire outer periphery. The inner peripheral surface is configured to be pressable. In addition to this, as shown in FIG. 24B, the outer peripheral surface of the annular elastic body 31i can be formed in a polygon such as a hexagon. Further, in this case, by arranging the corner portion of the annular elastic body 31 i so as to correspond to the position of the protruding piece portion 50 c of the conductive member 50, the protruding piece portion 50 c is surely pressed against the inner peripheral surface of the photosensitive drum 2. be able to.

  The cross-sectional shape of the annular elastic body 31i may be a circle shown in FIG. 25A, a rectangle shown in FIG. 25B, or other shapes. As shown in FIG. 25C, when the annular elastic body 31i is in a free state (a state where it is not attached to the support member 31), it does not necessarily have to be formed in an annular shape.

  Further, the outer peripheral shape of the gap forming portion 31e in the support member 31 may be a circle as shown in FIG. 26 (a) or a polygon such as a hexagon as shown in FIG. 26 (b). May be. For example, by attaching the annular elastic body 31i shown in FIG. 25 (c) to the hexagonal gap forming portion 31e shown in FIG. 26 (b), the annular elastic body 31i is deformed into a hexagonal shape, It is also possible to press the conductive member 50.

FIG. 27 shows another modification of the conductive member 50.
The conductive member 50 shown in FIG. 27A is provided with four rectangular protrusions 50c at equal intervals in the circumferential direction. Other than that, it is comprised similarly to the electrically-conductive member 50 shown in FIG. Thus, by increasing the number of the projecting piece portions 50c, the number of contact portions (first contact portions A) with the photosensitive drum 2 can be increased, and more stable conduction can be ensured.

  On the other hand, the conductive member 50 shown in FIG. 27B is provided with only one protruding piece 50c. By using a single projecting piece 50c, the size of the conductive member 50 can be reduced and the cost can be reduced. In the present modification, the shape of the projecting piece 50c is formed in a triangular shape whose width decreases from the inner diameter side toward the outer diameter side. In this case, the width of the root portion (inner diameter side) of the projecting piece 50c can be increased, and the projecting piece 50c is not easily tilted even if it contacts the photosensitive drum 2, so that the tip ( Stable conduction can be ensured with a low contact pressure with the photosensitive drum 2 on the outer diameter side.

  In the conductive member 50 shown in FIG. 27C, a rectangular piece 50e is disposed at a position where the shaft 40 is inserted. In this case, the shaft 40 is configured not to penetrate the electric member 50. In the present modification, the protrusion 50c that contacts the inner peripheral surface 2c of the photosensitive drum 2 is provided with one that is formed in a triangular shape that narrows toward the outer diameter side. As a result, the projecting piece portion 50c is less likely to fall even if it contacts the photosensitive drum 2, and stable conduction can be ensured in a state where the contact pressure with the photosensitive drum 2 is low at the tip of the projecting piece portion 50c. it can. In addition, two holes 50f are formed in the conductive member 50 in place of the notches at positions where the convex portions 31d (see FIG. 7 and the like) of the support member 31 are inserted.

  The conductive member 50 shown in FIG. 27 (d) has a plurality of triangular projecting piece portions 50c that become thinner toward the outer diameter side, and the projecting piece portions 50c are arranged without being spaced apart from each other. Yes. Also in this case, the number of contact portions (first contact portion A) with the photosensitive drum 2 can be increased, and more stable conduction can be ensured. Further, since the width of the root portion of the projecting piece 50c is formed large, the projecting piece 50c is unlikely to fall down even if it contacts the photoconductor drum 2, and the photosensitive drum 2 and the photosensitive drum 2 at the tip of the projecting piece 50c. It is also possible to ensure stable conduction with a low contact pressure.

  In the modification shown in FIG. 27 (e), the outer diameter D 1 of the conductive member 50 is formed larger than the inner diameter D 2 of the photosensitive drum 2, and radial notches 50 g are formed on the outer peripheral edge of the conductive member 50. . The plurality of pieces 50h formed between the notches 50g can be independently bent, and when the conductive member 50 is inserted into the photosensitive drum 2, these pieces 50h become the photosensitive drum. 2 functions as a first contact portion A that contacts the inner peripheral surface 2c.

  By the way, when the support member 31 to which the conductive member 50 is attached is inserted into the photosensitive drum 2, the protruding piece 50 c of the conductive member 50 is in sliding contact with the inner peripheral surface 2 c of the photosensitive drum 2. A tensile force acts on the conductive member 50 toward the tip end side of the projecting piece 50c. At this time, it is preferable to provide a plurality of projecting piece portions 50c at equal intervals, for example, as shown in FIG. 8 and FIG. 27A, so that the conductive member 50 does not move due to the pulling force. As a result, the tensile force due to the sliding contact with the inner peripheral surface 2c of the photosensitive drum 2 can be applied evenly in the circumferential direction of the conductive member 50, so that the conductive member 50 is not easily displaced in the radial direction. In addition, even when the conductive member 50 shown in FIGS. 27D and 27E is used, the tensile force due to the sliding contact with the photosensitive drum 2 can be applied evenly in the circumferential direction of the conductive member 50, The displacement of the member 50 can be suppressed.

FIG. 28 shows a modification of the cut 50b provided at the position where the shaft 40 of the conductive member 50 is inserted.
As shown in FIG. 28A, the cut 50b may be formed in a single character type in addition to the cross character type. Further, as in a notch 50b shown in FIG. 28 (b), incisions may be further added radially to the cross-shaped notch. In this case, the number of contact portions with the shaft 40 can be increased, and more stable conduction can be ensured.

  The cut 50b shown in FIG. 28C is formed in a polygonal line shape, and the cut 50b crosses the range where the shaft 40 is inserted a plurality of times. Also in this case, the number of contact portions with the shaft 40 can be increased, and more stable conduction can be ensured. Further, the cut 50b may be formed in a wavy shape having a curved corner.

  A cut 50b shown in FIG. 28 (d) forms a plurality of cuts in the vertical direction of the figure with respect to one cut in the horizontal direction of the figure. Thereby, the contact part of the electrically-conductive member 50 and the shaft 40 increases, and stable conduction | electrical_connection can be ensured. Further, in the present modification, the length of the vertical cut in the drawing is changed in accordance with the outer diameter shape of the shaft 40. Thereby, the range which forms a notch can be suppressed to the minimum necessary, and there exists an advantage which can improve the rigidity of the electrically-conductive member 50 and can make the size compact.

  The cuts 50b shown in FIG. 28 (e) are formed in a radial shape, and their centers are arranged at positions deviated from the center of the range where the shaft 40 is inserted. When the shaft 40 is inserted into the notch 50b, the conductive member 50 can be brought into contact with the shaft 40 at different positions in the axial direction of the shaft 40, as shown in FIG. I can expect.

Hereinafter, the operations and effects common to each of the reference examples and the embodiments of the present invention will be described with reference to FIGS. 4 and 5.
In FIG. 4, when a driving force from a driving device (not shown) is transmitted to the gear portion 32 c provided on the left support member 32 and the support member 32 is rotated, the photosensitive drum 2, the support member 31, and the conductive member 50. Rotates. At this time, the conductive member 50 rotates while sliding on the outer peripheral surface of the shaft 40 in the second contact portion B shown in FIG. 5. However, the conductive member 50 according to the present invention is formed of a flexible member. Therefore, wear hardly occurs between the conductive member 50 and the shaft 40.

Thereby, in a reference example and embodiment of this invention, generation | occurrence | production of the noise by abrasion can be suppressed or prevented highly in the sliding part of the electrically-conductive member 50 and the shaft 40. FIG. Further, according to the configuration of the present invention, it is not necessary to apply a conductive lubricant (for example, conductive grease or the like) for the purpose of reducing sliding resistance to the contact portion between the conductive member 50 and the shaft 40. Therefore, the load on the environment can be reduced. In addition, since the conductive member 50 is not oxidized, it is possible to ensure stable conduction over a long period of time. In addition, the conductive member 50 according to the present invention can be manufactured by a very simple process of cutting a sheet material into a predetermined shape and forming a notch or a hole. Can be obtained.

  Each of the embodiments according to the present invention is an example in which the configuration of the present invention is applied to the grounding structure of the photosensitive drum. However, the configuration of the present invention can be applied to the grounding structure of a rotating body other than the photosensitive drum. is there. For example, the configuration of the present invention can be applied to the ground structure of the drive roller 9 shown in FIG. Hereinafter, an embodiment in which the configuration of the present invention is applied to the ground structure of the drive roller 9 will be described with reference to FIG.

FIG. 30 is a cross-sectional view around one end of the drive roller 9.
As shown in FIG. 30, the drive roller 9 includes a cylindrical conductive substrate 9a and a rubber coating layer 9b disposed on the outer peripheral surface of the conductive substrate 9a. Further, a support member 71 made of non-conductive resin or the like is inserted and fixed in one end of the drive roller 9, and the drive roller 9 is connected to the conductive shaft 60 by the support member 71. It is rotatably supported.

  In addition to stretching the intermediate transfer belt 8 shown in FIG. 1, the drive roller 9 also serves to flow a part of the current generated by the bias applied to the secondary transfer roller 12 shown in FIG. 1 to the ground. . However, when filming occurs on the surface of the drive roller 9 due to the components of the intermediate transfer belt 8, foreign matters mixed in the belt, toner, or the like, the resistance value may increase. In this state, when the secondary transfer bias is repeatedly applied, the coating layer of the driving roller 9 is charged, and abnormal discharge may occur over time, leaving a discharge mark on the image. Further, the current during discharge may flow backward to the high-voltage power supply side of the secondary transfer roller 12 and cause an abnormality in the high-voltage substrate.

Therefore, as shown in FIG. 30, the driving roller 50 is brought into contact with the inner peripheral surface of the driving roller 9 and the outer peripheral surface of the shaft 60 by bringing the conductive member 50 made of a sheet-like member having conductivity and flexibility into contact with the driving roller. Conductivity can be ensured between 9 and the shaft 60. Further, when the drive roller 9 is rotated, the conductive member 50 is also rotated together with the support member 71, and the conductive member 50 slides at the contact portion with the shaft 60. However, as in the case of the above embodiments of the present invention. Since there is almost no wear between the conductive member 50 and the shaft 60, the generation of abnormal noise can be highly suppressed or prevented. In addition, it is not necessary to apply a conductive lubricant (for example, conductive grease) for the purpose of reducing sliding resistance to the contact portion between the conductive member 50 and the shaft 60, thereby reducing the burden on the environment. it can. Moreover, since the conductive member 50 is not oxidized, it is possible to ensure stable conduction over a long period of time. In FIG. 30, the support member 71 and the conductive member 50 are configured in the same manner as the first reference example shown in FIG. 5 and the like, but other reference examples or configurations according to the embodiments of the present invention are used. It is also possible to apply.

  In addition, for example, an outer ring fixed to the inner peripheral surface of the rotating body and an inner ring fixed to the outer peripheral surface of the shaft include support members that rotatably support the rotating body such as the photosensitive drum and the driving roller with respect to the shaft. It is also possible to configure the bearing with a spherical body that rolls between the outer ring and the inner ring. In this case, it is also possible to attach the conductive member to a bearing (support member) so as not to rotate with respect to the shaft. In this case, the conductive member slides with respect to the inner peripheral surface of the rotating body. Even in such a configuration, by configuring the conductive member with a flexible member, it is possible to suppress wear between the conductive member and the rotating body and to highly suppress or prevent the generation of abnormal noise. Is possible.

  The embodiment of the present invention has been described above, but the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the gist of the present invention. The present invention is not limited to the electrophotographic image forming apparatus shown in FIG. 1, and is applied to a rotating body that requires grounding in an electrostatic recording image forming apparatus or an image forming apparatus such as a magnetic recording system. It is possible.

1 Process unit 2 Photosensitive drum (rotating body)
9 Drive roller (rotating body)
24 Image carrier unit 25 Image forming apparatus main body 31 Support member 31c Front end 31d in the inserting direction 31d Convex part 31e Gap forming part 31g Restricting part 31h Elastic arm (pressing member)
31i Annular elastic body (pressing member)
40 Shaft 50 Conductive member 50a Notch 50b Notch 50c Projection piece 60 Shaft 71 Support member 310 Inclined surface A 1st contact part B 2nd contact part

JP 11-249495 A JP 2000-48873 A Japanese Patent No. 3950635

Claims (17)

A cylindrical rotating body;
A shaft inserted into the rotating body;
A support member disposed between the rotating body and the shaft and rotatably supporting the rotating body with respect to the shaft;
A flexible conductive member attached to the support member and brought into contact with the inner peripheral surface of the rotating body and the outer peripheral surface of the shaft ;
In a state where the support member is aligned at a position where the support member can be inserted into the rotating body, the rotating member has a portion protruding to the outer peripheral side from the inner peripheral surface of the rotating body when viewed from the axial direction of the rotating body. A rotating member grounding structure characterized in that a pressing member elastically deformable in the radial direction is provided on the supporting member, and the conductive member is pressed against the inner peripheral surface of the rotating member by the pressing member. . The rotating body according to claim 1, wherein an inclined surface that inclines in an inner diameter direction toward the front in the insertion direction of the rotating body is provided at a portion of the pressing member that protrudes to the outer peripheral side from the inner peripheral surface of the rotating body. Earth structure. The conductive member is attached to the support member, and when the support member is positioned at a position where the support member can be inserted into the rotary body, the conductive member is an inner circumference of the rotary body when viewed from the axial direction of the rotary body. a first contact portion disposed on the outer peripheral side than the surface of the rotary body according to claim 1 or 2 and a second contact portion which is disposed at a position for inserting said shaft of said rotating body Earth structure. The conductive member is attached to the front end of the support member in the insertion direction with respect to the rotating body, and at least a portion of the outer peripheral surface of the support member corresponding to the first contact portion of the conductive member on the front end side in the insertion direction is rotated. The earth structure of the rotating body according to claim 3 , wherein a gap forming portion is provided for forming a gap between the inner peripheral surface of the member . The ground structure of the rotating body according to claim 3 or 4, wherein a plurality of the first contact portions are arranged in a circumferential direction of the rotating body. The ground structure for a rotating body according to claim 5 , wherein the plurality of first contact portions are arranged at equal intervals in a circumferential direction of the rotating body. The earth structure of the rotating body according to any one of claims 3 to 6, wherein a width on an inner diameter side of the first contact portion is formed larger than a width on an outer diameter side . The earth structure of the rotating body according to any one of claims 3 to 7, wherein the conductive member is formed of a rectangular sheet material, and a corner portion of the sheet material is the first contact portion . Wherein the second contact portion, the ground structure of the rotary body according to any one of claims 3 to 8 which is constituted by forming a can be inserted cut the shaft to the conductive member. The ground structure for a rotating body according to any one of claims 3 to 8 , wherein the second contact portion is configured by a plurality of slits extending radially from a portion through which the shaft is inserted . The ground structure for a rotating body according to any one of claims 1 to 10, wherein the support member is provided with a protrusion, and the conductive member is provided with a notch, a slit, or a hole for inserting the protrusion . 12. The ground structure for a rotating body according to claim 1, wherein the support member is provided with a restricting portion that abuts on an outer edge of the conductive member to restrict radial movement . An image carrier constituted by a rotating body capable of carrying an image on its surface, a shaft inserted into the image carrier, and the image carrier disposed between the image carrier and the shaft. An image carrier unit including a support member rotatably supported with respect to
13. An image carrier unit comprising the rotating member ground structure according to claim 1 as the ground structure of the image carrier . The image processing apparatus according to claim 13, wherein at least one of a charging unit, a developing unit, and a cleaning unit and an image carrier are integrally provided in a process unit configured to be detachable from the main body of the image forming apparatus. A process unit comprising a carrier unit . An image forming apparatus comprising the process unit according to claim 14 . An image forming apparatus comprising the rotating body grounding structure according to claim 1 . In the grounding method of the rotating body in which the rotating body is rotatably supported with respect to the shaft by a support member disposed between the cylindrical rotating body and the shaft,
The support member has a portion protruding from the inner peripheral surface of the rotary body to the outer peripheral side when viewed from the axial direction of the rotary body in a state where the support member is aligned at a position where the support member can be inserted into the rotary body. And a pressing member elastically deformable in the radial direction of the rotating body,
By attaching a flexible conductive member to the support member and assembling the support member, the rotating body, and the shaft, the conductive member is brought into contact with the inner peripheral surface of the rotating body and the outer peripheral surface of the shaft, A method of grounding a rotating body, wherein the conductive member is held in a state of being pressed against an inner peripheral surface of the rotating body by the pressing member, and the rotating body and the shaft are electrically connected .

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