Drum cartridge

Abstract

To provide a drum cartridge facilitating film application.SOLUTION: A drum cartridge comprises a photosensitive drum, a conveyance roller (a first conveyance roller 110), a drum frame 150, a guide 151 and a film 140. The photosensitive drum and the conveyance roller are, respectively, rotatable about a first shaft and a second shaft 110X extending in the axial direction. The conveyance roller conveys a sheet S toward the photosensitive drum. The conveyance roller is capable of collecting paper dust from the sheet S. The drum frame 150 supports the photosensitive drum and the conveyance roller. The guide 151 is located between the conveyance roller and the photosensitive drum, and guides the sheet S conveyed by the conveying roller. The guide 151 includes a guide surface 152 for guiding the sheet and a back surface 153 on the back side of the guide surface 152. The film 140 extends in the axial direction, one end of which is stuck to the back surface, and the other end of which is in contact with the conveyance roller, thereby closing a gap 158 between the guide 151 and the conveyance roller.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a drum cartridge including a photosensitive drum. [Background technology]

[0002] Conventionally, a drum cartridge has been known that is capable of removing paper dust from sheets and includes a first transport roller that transports the sheets (Patent Document 1). The first transport roller is one of a pair of registration rollers. This drum cartridge is provided with a film that seals the gap between the first transport roller and the drum frame. The film is attached to the end face of a plate-shaped guide that guides the sheets transported by the first transport roller. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-201316 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the configuration of Patent Document 1 has a problem in that the area of the surface to which the film is attached is small, making it difficult to attach.

[0005] Therefore, an object of the present disclosure is to provide a drum cartridge that makes it easy to attach a film that seals the gap between a conveying roller capable of collecting paper dust and a drum frame. [Means for solving the problem]

[0006] To achieve the above-mentioned object, the drum cartridge of the first disclosure includes a photosensitive drum, a transport roller, a drum frame, a guide, and a film. The photosensitive drum is rotatable about a first shaft extending in the axial direction. The transport roller is rotatable about a second shaft extending in the axial direction. The transport roller transports the sheet toward the photosensitive drum. The transport roller is capable of collecting paper dust from the sheet. The drum frame supports the photosensitive drum and the transport roller. The guide is positioned between the transport roller and the photosensitive drum, and guides the sheet transported by the transport roller. The guide has a guide surface that guides the sheet and a back surface behind the guide surface. The film extends in the axial direction, one end of which is attached to the back surface, and the other end of which is in contact with the transport roller, thereby closing the gap between the guide and the transport roller.

[0007] According to the first disclosure, the film is attached to the rear surface of the guide, making it easy to attach the film.

[0008] The second disclosure is the first disclosure, wherein the back surface may have an attachment surface to which a film is attached, and a third inclined surface extending from the end of the attachment surface closest to the conveying roller toward the conveying roller, the first inclined surface inclined relative to the attachment surface so as to move away from the sheet guided by the guide as it approaches the conveying roller.

[0009] By providing the first inclined surface on the rear surface, the leading edge of the film can be oriented in an appropriate direction.

[0010] In a third disclosure, in the first disclosure, the guide may have a protrusion protruding from a rear surface at a central portion in the axial direction. The film may include a first film arranged on one side of the protrusion in the axial direction, and a second film separate from the first film and arranged on the other side of the protrusion in the axial direction.

[0011] By having the first film and the second film, the film can be attached while avoiding the protrusions.

[0012] The fourth disclosure is that in the third disclosure, the protrusion may have a second inclined surface facing the conveying roller, the second inclined surface being inclined so as to move away from the conveying roller as it moves toward one side in the axial direction, and a third inclined surface facing the conveying roller, the third inclined surface being inclined so as to move away from the conveying roller as it moves toward the other side in the axial direction.

[0013] When there is a protrusion on the back surface of the guide, the protrusion has a first inclined surface and a second inclined surface, so that the paper dust collected by the conveying roller can flow from the protrusion to one side or the other in the axial direction.

[0014] In a fifth disclosure, in the first disclosure, the guide may have a reference surface extending from the back surface in a direction intersecting the back surface and extending parallel to the axial direction, and the film may be attached to the back surface along the reference surface.

[0015] By attaching the film along a reference plane that extends in a direction intersecting the back surface, it becomes easy to attach the film to a predetermined position.

[0016] In a sixth disclosure, in the first disclosure, the drum cartridge may be detachably attached to a housing of the image forming apparatus.

[0017] A seventh disclosure is the sixth disclosure, wherein a toner cartridge that contains toner may be detachably attached to the drum cartridge.

[0018] According to an eighth disclosure, in the first disclosure, the drum cartridge may further include a frictionally charged member that contacts the transport roller. The transport roller may be configured to be charged by contact with the frictionally charged member and to electrically attract and collect paper dust on the sheet.

[0019] A ninth disclosure is the eighth disclosure, wherein the frictional charging member may be made of a sponge.

[0020] A tenth disclosure is any one of the first to ninth disclosures, wherein the conveying roller has a roller body made of metal and a coating layer made of fluororesin that covers the outer peripheral surface of the roller body. [Effects of the Invention]

[0021] According to the present disclosure, the film is attached to the back surface of the guide surface of the guide, making it easy to attach the film. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 2 is a cross-sectional view of the image forming apparatus. [Figure 2] FIG. 2 is a cross-sectional view of the drum cartridge. [Figure 3] FIG. 3 is an enlarged cross-sectional view of the first conveyor roller and its surroundings. [Figure 4] FIG. 2 is a perspective view of the drum cartridge. [Figure 5] FIG. 5 is a partially enlarged view of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0023] Next, an embodiment of the present disclosure will be described in detail with reference to the drawings as appropriate. As shown in FIG. 1, the image forming apparatus 1 includes a housing 10, a sheet supply unit 20, an image forming unit 30, and a sheet discharge unit 90.

[0024] In the following description, the axial direction of the photosensitive drum 51 is referred to as the first direction (see FIG. 4). The direction intersecting the first direction is referred to as the second direction. Preferably, the second direction is perpendicular to the first direction. The direction intersecting the first and second directions is referred to as the third direction. Preferably, the third direction is perpendicular to the first and second directions. In the first, second, and third directions, the direction indicated by the arrow in each drawing is referred to as one side, and the direction opposite to the arrow is referred to as the other side. For example, in FIG. 1, the right is one side of the second direction, and the left is the other side of the second direction. Furthermore, the top is one side of the third direction, and the bottom is the other side of the third direction.

[0025] The housing 10 has a cover 11 at the end on the other side in the second direction. The housing 10 has a discharge tray 12 on one side in the third direction.

[0026] The sheet supply unit 20 includes a sheet tray 21 that stores sheets S such as paper, a pickup roller 22, a separation roller 23, a separation pad 24, a conveyance roller 25, and a second conveyance roller 26.

[0027] The sheet supply unit 20 feeds out the sheets S in the sheet tray 21 using a pickup roller 22, and separates the sheets one by one using a separation roller 23 and a separation pad 24. Then, the sheet supply unit 20 conveys the sheets S toward the photosensitive drum 51 using a conveyance roller 25, a second conveyance roller 26, and a first conveyance roller 110, which will be described later.

[0028] The second conveying roller 26 is a roller that rotates when a driving force is input. The second conveying roller 26 is held in the housing 10. The leading edge of the sheet S comes into contact with the second conveying roller 26, thereby determining the position of the leading edge of the sheet S. The second conveying roller 26 conveys the sheet S, whose leading edge has been positioned, toward the photosensitive drum 51.

[0029] The image forming section 30 includes an exposure device 40, a drum cartridge 50, a plurality of toner cartridges 60, a transfer unit 70, and a fixing device 80.

[0030] The exposure device 40 is located on one side in the third direction within the housing 10 relative to the drum cartridge 50. The exposure device 40 exposes the surface of the photosensitive drum 51 by emitting a plurality of light beams indicated by dashed dotted lines.

[0031] The drum cartridge 50 includes a plurality of photosensitive drums 51, a plurality of chargers 52 corresponding to the plurality of photosensitive drums 51, and a drum frame 150 (see FIG. 2). The drum cartridge 50 can be attached to and detached from the housing 10 of the image forming apparatus 1 in a second direction by opening the cover 11. When attached to the housing 10, the drum cartridge 50 is positioned between the sheet tray 21 and the exposure device 40. A toner cartridge 60 can be attached to and detached from the drum cartridge 50 (see FIG. 2). The drum cartridge 50 can be attached to and detached from the housing 10 with the toner cartridge 60 attached.

[0032] The photosensitive drum 51 is rotatable about a first shaft 51X extending in a first direction. The photosensitive drums 51 are arranged side by side in a second direction.

[0033] The drum frame 150 supports a plurality of photosensitive drums 51, a charger 52, a first conveying roller 110, and a toner cartridge 60 attached to the drum cartridge 50.

[0034] The toner cartridge 60, while attached to the drum cartridge 50, can be detachably attached to the housing 10 together with the drum cartridge 50. The multiple toner cartridges 60 contain toner of different colors, for example, yellow, magenta, cyan, and black. The toner cartridge 60 includes a developing roller 61, a supply roller 62, a layer thickness regulating blade 63, a toner containing section 64 that contains toner, and an agitator 65.

[0035] The toner cartridge 60 supplies the toner in the toner storage section 64 to the supply roller 62 while stirring it with the agitator 65, and then supplies it from the supply roller 62 to the developing roller 61. Then, as the developing roller 61 rotates, the toner supplied to the developing roller 61 enters between the developing roller 61 and the layer thickness regulating blade 63, and is carried by the developing roller 61 at a constant thickness.

[0036] The transfer unit 70 is located between the sheet tray 21 and the drum cartridge 50 attached to the housing 10. The transfer unit 70 includes a drive roller 71, a driven roller 72, a conveyor belt 73, and multiple transfer rollers 74. The drive roller 71 and the driven roller 72 are spaced apart in the second direction. The conveyor belt 73 is an endless belt. The conveyor belt 73 is stretched between the drive roller 71 and the driven roller 72. The transfer roller 74 is located inside the conveyor belt 73, and sandwiches the conveyor belt 73 between the transfer roller 74 and the photosensitive drum 51.

[0037] The fixing device 80 includes a heating roller 81 that heats the sheet S, and a pressure roller 82. The pressure roller 82 is pressed against the heating roller 81.

[0038] The image forming unit 30 charges the surface of the photosensitive drum 51 using the charger 52. Then, the image forming unit 30 exposes the surface of the photosensitive drum 51 using the exposure device 40. As a result, an electrostatic latent image is formed on the photosensitive drum 51. Next, the image forming unit 30 supplies toner from the development roller 61 to the photosensitive drum 51. As a result, the electrostatic latent image on the photosensitive drum 51 is made visible, and a toner image is formed on the photosensitive drum 51.

[0039] Next, the image forming unit 30 transfers the toner image on the photosensitive drum 51 onto the sheet S by transporting the sheet S supplied from the sheet supply unit 20 between the photosensitive drum 51 and the transfer roller 74. Then, the image forming unit 30 transports the sheet S onto which the toner image has been transferred between the heating roller 81 and the pressure roller 82, thereby thermally fixing the toner image onto the sheet S and forming an image on the sheet S.

[0040] The sheet discharge section 90 has a conveying roller 91 and a discharge roller 92. The conveying roller 91 conveys the sheet S on which an image has been formed toward the discharge roller 92. The discharge roller 92 discharges the sheet S onto the discharge tray 12 of the housing 10.

[0041] As shown in FIGS. 2 and 4, the drum cartridge 50 includes a plurality of photosensitive drums 51, a charger 52, and a paper dust cleaning unit CL.

[0042] The paper dust cleaning unit CL collects paper dust adhering to the sheet S. As shown in FIG. 3, the paper dust cleaning unit CL includes a first conveyor roller 110, a paper dust storage unit 115, a frictional charging member 118, a lever 160, a spring 168, and a film 140.

[0043] The first conveying roller 110 is a roller that can rotate about a second shaft 110X that extends in the first direction, and is located at the other end of the drum frame 150 in the second direction. The first conveying roller 110 is located upstream of the multiple photosensitive drums 51 in the conveying direction of the sheet S. In other words, the first conveying roller 110 is located at the other end of the drum frame 150 in the second direction.

[0044] The first conveyor roller 110 conveys the sheet S toward the photosensitive drum 51. More specifically, when the drum cartridge 50 is installed in the housing 10 of the image forming apparatus 1, the first conveyor roller 110 comes into contact with the second conveyor roller 26 of the image forming apparatus 1 and conveys the sheet S sandwiched between the first conveyor roller 110 and the second conveyor roller 26 toward the photosensitive drum 51. The first conveyor roller 110 feeds the sheet S sandwiched between the first conveyor roller 110 and the second conveyor roller 26 toward one side in the second direction. More specifically, the first conveyor roller 110 feeds the sheet S slightly obliquely toward one side in the third direction with respect to the second direction. The sheet S fed from the first conveyor roller 110 is guided by a guide 151 and then conveyed along the surface of the conveyor belt 73 toward one side in the second direction. Hereinafter, the direction in which the sheet S is conveyed by the first conveyor roller 110 toward one side in the second direction will be simply referred to as the "conveyance direction."

[0045] The first conveyor roller 110 is configured to have a roller body made of metal and a coating layer made of fluororesin that covers the outer circumferential surface of the roller body.

[0046] The first conveyor roller 110 is capable of collecting paper dust from the sheet S being conveyed between the first conveyor roller 110 and the second conveyor roller 26. More specifically, the first conveyor roller 110 is capable of collecting the paper dust on the sheet S by electrically attracting it. Specifically, the outer circumferential surface of the first conveyor roller 110 is charged to a polarity opposite to the charging characteristics of the paper dust by contact with the frictional charging member 118, thereby electrically attracting and collecting the paper dust on the sheet S.

[0047] The paper dust collection unit 115 has a box shape and is capable of collecting paper dust collected by the first conveyor roller 110. The paper dust collection unit 115 has a collection space capable of collecting paper dust.

[0048] The frictional charging member 118 is located inside the paper dust container 115 and is in contact with the first conveyor roller 110. The frictional charging member 118 is made of a sponge.

[0049] Lever 160 is located inside paper dust container 115. Lever 160 has a first arm 161 and a second arm 162. Lever 160 is held by drum frame 150 so as to be rotatable about a rotation axis 160X between first arm 161 and second arm 162. A frictional charging member 118 is fixed to second arm 162.

[0050] The spring 168 is a tension spring. One end of the spring 168 engages with the tip of the first arm 161 of the lever 160. The other end of the spring 168 engages with a hook 159 of the drum frame 150. The lever 160 is constantly biased in the counterclockwise direction in FIG. 3 by the biasing force of the spring 168. This causes the frictional charging member 118 to be pressed against the outer circumferential surface of the first conveyor roller 110.

[0051] The frictional charging member 118 comes into contact with the first conveyor roller 110 to charge the outer circumferential surface of the first conveyor roller 110, and also scrapes the paper dust collected by the first conveyor roller 110 from the first conveyor roller 110. The paper dust scraped off from the first conveyor roller 110 is stored in the paper dust storage unit 115.

[0052] Here, the drum frame 150 has a guide 151 downstream of the first conveyor roller 110 in the conveying direction. The guide 151 is located between the first conveyor roller 110 and the photosensitive drum 51. The guide 151 guides the sheet S conveyed by the first conveyor roller 110. The guide 151 has a guide surface 152 that guides the sheet S, a back surface 153 on the back side of the guide surface 152, a reference surface 154, and a protrusion 155 (see FIGS. 4 and 5).

[0053] The guide surface 152 has a first guide surface 152 A and a second guide surface 152 B. The first guide surface 152 A is located upstream of the second guide surface 152 B in the conveying direction of the sheet S by the first conveying roller 110. The first guide surface 152A is a flat surface extending in the second direction. More specifically, the first guide surface 152A has an inclined surface 152C at its upstream end in the conveying direction that is inclined with respect to the second direction so as to be positioned on one side in the third direction as it approaches the first conveying roller 110. The second guide surface 152B is concave in a bow shape toward one side in the third direction. The upstream end of the second guide surface 152B in the conveying direction is positioned closer to the one side in the third direction than the downstream end of the first guide surface 152A in the conveying direction. This forms a step between the first guide surface 152A and the second guide surface 152B.

[0054] A gap 158 is formed between the upstream end of the guide 151 in the conveying direction and the first conveying roller 110. The gap 158 serves as an inlet through which paper dust captured from the sheet S by the first conveying roller 110 enters the paper dust storage unit 115.

[0055] The back surface 153 is the surface behind the guide surface 152. More specifically, the back surface 153 is the surface behind the first guide surface 152A. The back surface 153 has an attachment surface 153A and a first inclined surface 153B. The attachment surface 153A is the surface to which the film 140 is attached. The attachment surface 153A is a flat surface extending in the second direction. The first inclined surface 153B is a surface that extends from an end of the attachment surface 153A that is close to the first conveyor roller 110 toward the first conveyor roller 110. The first inclined surface 153B is inclined with respect to the attachment surface 153A so as to move away from the sheet S guided by the guide 151 as it approaches the first conveyor roller 110.

[0056] The reference surface 154 is a surface that extends from the back surface 153 in a direction that intersects with the back surface 153. Specifically, the reference surface 154 extends from the end of the attachment surface 153A that is on the downstream side in the conveyance direction toward one side in the third direction. The reference surface 154 also extends parallel to the first direction.

[0057] The film 140 is a rectangular resin film that extends in the first direction. One end of the film 140 is attached to the back surface 153, and the other end is in contact with the first conveyor roller 110. The film 140 fills the gap 158 between the guide 151 and the first conveyor roller 110. Specifically, the film 140 is attached to the attachment surface 153A with double-sided tape TP, with the downstream end in the conveyance direction aligned with the reference surface 154. The film 140 bends toward one side in the third direction by contacting the first inclined surface 153B, and the leading end, which is the free end, is aligned with the surface of the first conveyor roller 110. The leading end of the film 140 faces downstream in the rotation direction of the first conveyor roller 110.

[0058] As shown in FIGS. 4 and 5, the protrusion 155 protrudes from the rear surface 153. Note that in FIGS. 4 and 5, some components of the drum frame 150 are omitted so that the film 140 can be seen. The protrusion 155 is located in the center of the rear surface 153 in the first direction. Although not shown, a recess on the rear side of the protrusion 155 houses a sensor that detects the passage of the sheet S. The protrusion 155 has a second inclined surface 155A and a third inclined surface 155B. The second inclined surface 155A faces the first conveyor roller 110. The second inclined surface 155A is inclined with respect to the first direction so as to move away from the first conveyor roller 110 toward one side in the first direction. The third inclined surface 155B faces the first conveyor roller 110. The third inclined surface 155B is inclined with respect to the first direction so as to move away from the first conveyor roller 110 toward the other side in the first direction.

[0059] Film 140 includes first film 140A and second film 140B that is separate from first film 140A. First film 140A is disposed on one side of protrusion 155 in the first direction. Second film 140B is disposed on the other side of protrusion 155 in the first direction.

[0060] In the image forming apparatus 1 configured as described above, the sheet S conveyed by the first conveyor roller 110 is guided by the guide surface 152 of the guide 151 and then conveyed between the multiple photosensitive drums 51 and the conveyor belt 73. At this time, the frictional charging member 118 is in contact with the rotating first conveyor roller 110, so that the surface of the first conveyor roller 110 is frictionally charged. Then, paper dust from the surface of the sheet S is attracted to the first conveyor roller 110 and adheres to the outer circumferential surface of the first conveyor roller 110. Then, as the first conveyor roller 110 rotates, the paper dust passes through the gap 158. Furthermore, the paper dust passes between the film 140 and the first conveyor roller 110 and enters the paper dust container 115.

[0061] The paper dust that enters the paper dust collection section 115 is scraped off the outer peripheral surface of the first conveyor roller 110 by the frictional charging member 118 and accumulates in the paper dust collection section 115 downstream in the conveyance direction of the frictional charging member 118. Here, because the back surface 153 of the guide 151 has a protrusion 155 in the center in the first direction, the paper dust scraped off by the frictional charging member 118 in the center in the first direction flows toward the protrusion 155. The paper dust is then swept to one side or the other in the first direction by the second inclined surface 155A or the third inclined surface 155B. In this way, the paper dust is stored in the collection space above the sticking surface 153A.

[0062] The drum cartridge 50 of the present disclosure can achieve the following effects. Because the film 140 is attached to the back surface 153 of the guide 151, it is easier to attach the film 140 than if the film 140 were attached to the end surface of the guide 151. Furthermore, if the film 140 were attached to the guide surface 152, there is a risk that the film 140 would be damaged if the sheet S came into contact with the film 140. However, in the drum cartridge 50 of the present disclosure, the sheet S does not come into contact with the film 140, so the film 140 is less likely to be damaged. Furthermore, because the film 140 includes the first film 140A and the second film 140B, even if a protrusion 155 is present on the back surface 153 of the guide 151, the film 140 can be attached while avoiding the protrusion 155.

[0063] The back surface 153 of the guide 151 has a protrusion 155, and the protrusion 155 has a second inclined surface 155A and a third inclined surface 155B, which allows the paper dust collected by the first conveying roller 110 to flow from the protrusion 155 to one side or the other in the first direction.

[0064] Furthermore, rear surface 153 of guide 151 has first inclined surface 153B, so that the leading edge of film 140 can be directed in an appropriate direction.

[0065] Furthermore, by attaching film 140 along reference surface 154 that extends in a direction intersecting rear surface 153, film 140 can be easily attached to a predetermined position.

[0066] Although one embodiment of the present disclosure has been described above, the present disclosure is not limited to the above-described embodiment and can be implemented with appropriate modifications.

[0067] For example, the member that removes paper dust from the first transport roller 110 may be a roller or a blade instead of the frictional charging member 118. Furthermore, the paper dust cleaning unit CL may include an auger that transports paper dust in the axial direction.

[0068] In addition, in the embodiment, the image forming device 1 and drum cartridge 50 are illustrated as having four photosensitive drums 51 and printing color images using four color toners, but the image forming device and drum cartridge may be, for example, an image forming device that prints color images using three or five color toners. Also, the image forming device and drum cartridge may be an image forming device that has only one photosensitive drum and prints monochrome images. The image forming device may be a printer, or a multifunction peripheral or copier that is equipped with a document reading device such as a flatbed scanner.

[0069] Furthermore, the elements described in the above-described embodiment and modifications can be implemented in appropriate combinations. [Explanation of symbols]

[0070] 50 drum cartridges 51 Photosensitive drum 110 First conveying roller 140 Film 150 drum frame 151 Guide 152 Guide surface 153 Back side

Claims

1. a photosensitive drum rotatable about a first axis extending in the axial direction; a conveying roller rotatable about a second shaft extending in the axial direction, the conveying roller conveying the sheet toward the photosensitive drum, and capable of collecting paper dust from the sheet; a drum frame supporting the photosensitive drum and the transport roller; a guide positioned between the conveying roller and the photosensitive drum, for guiding a sheet conveyed by the conveying roller, the guide having a guide surface for guiding the sheet and a back surface behind the guide surface; A drum cartridge characterized by comprising a film extending in the axial direction, one end of which is attached to the back surface and the other end of which contacts the conveying roller, thereby sealing the gap between the guide and the conveying roller.

2. The back surface is an attachment surface to which the film is attached; a third inclined surface extending from an end of the attachment surface close to the conveying roller toward the conveying roller, the third inclined surface being inclined with respect to the attachment surface so as to move away from the sheet guided by the guide as it approaches the conveying roller; 2. The drum cartridge according to claim 1, further comprising:

3. the guide has a protrusion protruding from the back surface at a central portion in the axial direction, The film is a first film disposed on one side of the protrusion in the axial direction; a second film separate from the first film and disposed on the other side of the projection in the axial direction; 2. The drum cartridge according to claim 1, further comprising:

4. The protrusion is a second inclined surface facing the conveying roller, the first inclined surface being inclined so as to move away from the conveying roller toward the one side in the axial direction; a third inclined surface facing the conveying roller, the second inclined surface inclined so as to move away from the conveying roller toward the other side in the axial direction; 4. The drum cartridge according to claim 3, further comprising:

5. the guide has a reference surface extending from the rear surface in a direction intersecting the rear surface and extending parallel to the axial direction, 2. The drum cartridge according to claim 1, wherein the film is attached to the rear surface along the reference surface.

6. 2. The drum cartridge according to claim 1, which is detachably mountable to a housing of an image forming apparatus.

7. 7. The drum cartridge according to claim 6, wherein the toner cartridge that contains the toner is detachable.

8. a frictional charging member in contact with the conveying roller; 2. The drum cartridge according to claim 1, wherein the transport roller is charged by contact with the frictional charging member, and electrically attracts and collects paper dust on the sheet.

9. 9. The drum cartridge according to claim 8, wherein the frictional charging member is made of a sponge.

10. 10. The drum cartridge according to claim 1, wherein the transport roller has a roller body made of metal and a coating layer made of fluororesin that covers the outer peripheral surface of the roller body.

Images