Processing unit and image forming device

Abstract

Provided is a processing unit capable of uniformly charging a photosensitive drum. The processing unit comprises: a photosensitive drum (13) on which a toner image is formed; a charging roller (50) which is pressed against the photosensitive drum (13) and charges the photosensitive drum (13); a cleaning roller (60) which is pressed against and cleans the charging roller (50); and a force applying member (80) which applies force to the charging roller (50) or the cleaning roller (60). The central axis of the photosensitive drum (13) is arranged at a position that does not overlap with a central axis (TL) passing through the central axis of the charging roller (50) and the central axis of the cleaning roller (60). The force applying direction of the force applying member (80) is on the same straight line as the central axis (TL).

Description

Technical Field

[0001] The present invention relates to a process unit for transferring a toner image and an image forming apparatus. Background Art

[0002] Conventionally, in an image forming apparatus using an electrophotographic method, a toner image is formed by charging the surface of a photosensitive drum so that toner adheres thereto, and the toner image is transferred to a sheet of paper to form an image. In recent years, various methods for charging a photosensitive drum have been proposed, for example, a contact charging method in which a conductive charging roller is brought into direct contact with the photosensitive drum is adopted (for example, see Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2007-121544 Summary of the invention

[0006] Technical Problems to be Solved by the Invention

[0007] The image forming device described in patent document 1 comprises: a charging roller that charges a charged body; a cleaning component that cleans the charging roller; a retaining component that maintains the relative positions of the charging roller and the cleaning component approximately constant; a housing on which the retaining component is slidably mounted; and a force applying component that applies force to the retaining component toward the charged body so that the charging roller is pressed into contact with the charged body.

[0008] In the above-mentioned image forming apparatus, there is a difference in the load applied to the charging roller at the two ends held by the holding member and the central part far from the holding member, and the shaft may be deformed. In addition, in the image forming apparatus, the force applying unit applies force to the holding member in the direction in which the charged body and the charging roller are opposite to each other, and the distance between the charged body and the charging roller varies due to the deformation of the shaft. As a result, the clamping width between the charged body and the charging roller becomes uneven, and the potential of the photosensitive body may vary.

[0009] The present invention has been made to solve the above-mentioned technical problems, and an object of the present invention is to provide a process unit and an image forming apparatus capable of uniformly charging a photosensitive drum without reducing the transmission efficiency of the pressing force to the charging roller.

[0010] Technical solutions for solving technical problems

[0011] The processing unit of the present invention is a processing unit for transferring a colorant image, and includes: a photosensitive drum having a colorant image formed on its surface; a charging roller which is in pressure contact with the photosensitive drum and charges the photosensitive drum; a cleaning roller which is in pressure contact with and cleans the charging roller; and a force-applying component which applies force to the charging roller or the cleaning roller, wherein the central axis of the photosensitive drum is arranged at a position that does not overlap with the central axis passing through the central axis of the charging roller and the central axis of the cleaning roller, and the force-applying direction of the force-applying component is on the same straight line as the central axis.

[0012] The processing unit of the present invention may also be configured to include a bearing portion that axially supports the central axis of the charging roller and the central axis of the cleaning roller, wherein the central axis of the charging roller and the central axis of the cleaning roller are fixed at a distance therebetween via the bearing portion.

[0013] The processing unit of the present invention may be configured such that the urging member includes: a charging urging member that urges the charging roller; and a cleaning urging member that urges the cleaning roller.

[0014] The process unit of the present invention may be configured such that the charging urging member is provided along the central axis, and the cleaning urging member is provided along a straight line passing through the central axis of the photosensitive drum and the central axis of the cleaning roller.

[0015] The process unit of the present invention may be configured such that the cleaning urging member is provided along the central axis, and the charging urging member is provided along a straight line passing through the central axis of the photosensitive drum and the central axis of the charging roller.

[0016] The process unit of the present invention may be configured such that the charging roller and the cleaning roller are arranged below the photosensitive drum in a height direction.

[0017] The processing unit of the present invention may be configured such that the charging roller is in a crown shape.

[0018] The image forming apparatus of the present invention includes the processing unit of the present invention.

[0019] Beneficial Effects

[0020] According to the present invention, since the charging roller is not applied straightly toward the central axis of the photosensitive drum, the deviation of the contact position with the photosensitive drum caused by the axial deformation of the charging roller can be alleviated, and the photosensitive drum can be uniformly charged without reducing the transmission efficiency of the pressing force to the charging roller. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a diagram schematically showing the configuration of an image forming apparatus according to a first embodiment of the present invention.

[0022] Figure 2 It is a schematic front view of a processing unit showing a first embodiment of the present invention.

[0023] Figure 3 This is an enlarged perspective view showing a partial end portion of the processing unit extracted and illustrated.

[0024] Figure 4 It is a side view schematically showing the relationship between the positions of the photosensitive drum, the charging roller, and the cleaning roller and the direction of force application.

[0025] Figure 5A It is a schematic side view showing the position and force application direction of a photosensitive drum and a charging roller in a comparative example.

[0026] Figure 5B Yes means Figure 5A Schematic front view of the photosensitive drum and charging roller.

[0027] Fig. 6A This is a schematic side view showing the positions and biasing directions of the photosensitive drum and the charging roller in the first embodiment of the present invention.

[0028] Figure 6B Yes means Fig. 6A A schematic front view of the photosensitive drum and the charging roller.

[0029] Figure 7 It is a schematic side view showing the position of a biasing member according to a modified example.

[0030] Figure 8 It is a schematic front view of a processing unit showing a second embodiment of the present invention.

[0031] Fig. 9 It is a schematic side view showing the force application direction of the first arrangement example.

[0032] Fig.10 It is a schematic side view showing the force application direction of the second arrangement example.

[0033] Fig.11 It is a schematic side view showing the force application direction of the third arrangement example. DETAILED DESCRIPTION

[0034] (First Embodiment)

[0035] Hereinafter, an image forming apparatus according to a first embodiment of the present invention will be described with reference to the drawings.

[0036] Figure 1 It is a schematic diagram showing the configuration of an image forming apparatus according to a first embodiment of the present invention.

[0037] The image forming apparatus 1 is configured to form a multi-color or monochrome image on a specified paper based on image data transmitted from the outside, and includes an exposure device 11, a developing device 12, a photosensitive drum 13, a cleaning device 14, a charger 15, an intermediate transfer belt device 16, a fixing device 17, a paper supply box 18, and a paper discharge tray 19.

[0038] The image data processed in the image forming apparatus is image data corresponding to a color image using each color of black (K), cyan (C), magenta (M), and yellow (Y). Therefore, four developing devices 12, four photosensitive drums 13, four chargers 15, and four cleaning devices 14 are provided to form four latent images corresponding to the respective colors, which are set to black, cyan, magenta, and yellow, respectively, and these constitute four image stations.

[0039] The photosensitive drum 13 is arranged approximately in the center of the image forming apparatus 1. The charger 15 charges the surface of the photosensitive drum 13 uniformly to a predetermined potential. The exposure device 11 exposes the surface of the photosensitive drum 13 to form an electrostatic latent image. The developing device 12 develops the electrostatic latent image on the surface of the photosensitive drum 13 and forms a toner image on the surface of the photosensitive drum 13. Through the above series of operations, a toner image of each color is formed on the surface of each photosensitive drum 13. The cleaning device 14 removes and recovers the residual toner on the surface of the photosensitive drum 13 after development and image transfer. In addition, for the structure of the photosensitive drum 13 and the vicinity of the charger 15, refer to the following description. Figure 2 Provide detailed explanation.

[0040] The intermediate transfer belt device 16 is arranged above the photosensitive drum 13, and includes an intermediate transfer belt 21, an intermediate transfer belt driving roller 22, an intermediate transfer belt driven roller 23, an intermediate transfer roller 24, an intermediate transfer belt cleaning device 25, and a tension roller 26. In addition, four intermediate transfer rollers 24 are provided corresponding to the image stations of the respective colors for YMCK.

[0041] The intermediate transfer belt driving roller 22 , the intermediate transfer belt driven roller 23 , the intermediate transfer roller 24 , and the tension roller 26 are configured to stretch the intermediate transfer belt 21 to move the surface of the intermediate transfer belt 21 in a predetermined direction (direction indicated by arrow C in the figure).

[0042] The intermediate transfer belt 21 moves in a circular motion in the direction of arrow C, and the residual colorant is removed and recovered by the intermediate transfer belt cleaning device 25. The colorant images of each color formed on the surface of each photosensitive drum 13 are transferred and overlapped in sequence, forming a color colorant image on the surface of the intermediate transfer belt 21.

[0043] The transfer roller 27a of the secondary transfer device 27 forms a nip region with the intermediate transfer belt 21, and sandwiches and transports the paper P conveyed through the paper conveying path S. When the paper P passes through the nip region, the toner image on the surface of the intermediate transfer belt 21 is transferred.

[0044] The paper feed cassette 18 is a cassette for accumulating paper P used for image formation, and is provided below the exposure device 11. The paper discharge tray 19 is provided above the image forming unit 1a and is a tray for placing paper P on which image formation has been completed.

[0045] In the image forming apparatus 1, the paper P from the paper feed cassette 18 is fed to the paper discharge tray 19 via the paper conveying path S via the secondary transfer device 27 and the fixing device 17. Along the paper conveying path S, a paper feed roller 31, a registration roller 32, a registration front roller 33, the fixing device 17, and a paper discharge roller 34 are arranged.

[0046] The paper feed roller 31 is provided near the end of the paper feed cassette 18, and feeds the paper P one by one from the paper feed cassette 18 to the paper transport path S. The registration roller 32 temporarily holds the paper P transported from the paper feed cassette 18, and transports the paper P to the transfer roller 27a at a timing that aligns the leading edge of the toner image on the photosensitive drum 13 with the leading edge of the paper P. The front registration roller 33 is a small roller for facilitating the transport of the auxiliary paper P.

[0047] The fixing device 17 is a fixing device of a belt fixing method, and a fixing belt 173 is wound around a plurality of rollers (here, a fixing roller 171 and a heating roller 172). The fixing belt 173 can transfer heat from the heating roller 172 to the fixing roller 171. In the fixing device 17, the pressure roller 174 is pressed against the fixing roller 171 via the fixing belt 173. In the fixing device 17, a sheet of paper P with an unfixed toner image formed thereon is received, and the sheet of paper P is sandwiched between the fixing belt 173 and the pressure roller 174 and conveyed. The fixed sheet of paper P is discharged to the discharge tray 19 by the discharge roller 34.

[0048] In the present embodiment, the fixing device 17 is a belt fixing type fixing device, but the present invention is not limited thereto and may be a type in which the pressure roller 174 directly presses the fixing roller 171 .

[0049] In the image forming apparatus 1, the photosensitive drum 13 and the charger 15 are part of the process unit 40. Next, the process unit 40 according to the first embodiment of the present invention will be described with reference to the drawings.

[0050] Figure 2 is a schematic front view showing a processing unit according to a first embodiment of the present invention, Figure 3 This is an enlarged stereoscopic view showing a portion of the end of the processing unit extracted. Figure 2In order to facilitate understanding of the structure of each part, the housing 41 and the bearing 70 are shaded. Figure 3 In the figure, the photosensitive drum 13, the charging roller 50, the cleaning roller 60, and the bearing portion 70 on one end side in the process unit 40 are extracted and shown for ease of illustration.

[0051] The process unit 40 according to the first embodiment of the present invention includes a photosensitive drum 13 , a charging roller 50 , and a cleaning roller 60 . Figure 1 In the image forming apparatus 1 shown, the toner image is transferred from the photosensitive drum 13 to the paper via the intermediate transfer belt 21, but the present invention is not limited thereto and the toner image may be directly transferred from the photosensitive drum 13 to the paper. In this case, the transfer roller 27a is pressed against the photosensitive drum 13 to form a nip region. Accordingly, the process unit 40 may also be configured to include the transfer roller 27a.

[0052] Both ends of the central axis (photoconductor axis 13 a ) of the photoconductor drum 13 in the width direction W are axially supported by the housing 41 .

[0053] The charging roller 50 is located below the photosensitive drum 13 in the height direction Z, and both ends of the central axis (charging axis 50 a ) in the width direction W are axially supported by the bearings 70 .

[0054] In this embodiment, the charging roller 50 is made of epichlorohydrin rubber, and its diameter is set to Φ12, and the diameter of the charging shaft 50a is set to Φ6. In addition, the charging roller 50 can also be a crown shape (i.e., a convex shape) with concave and convex portions in a manner that the diameter of the central portion in the width direction W is larger than that of the two end portions.

[0055] The cleaning roller 60 is located below the charging roller 50 in the height direction Z, and both ends of the central axis (cleaning shaft 60a) in the width direction W are axially supported by the bearing portion 70. In this embodiment, the cleaning roller 60 is made of polyurethane sponge and has a diameter of Φ11.3, and the diameter of the cleaning shaft 60a is set to Φ6.

[0056] The bearing parts 70 are respectively arranged at the two end parts in the width direction W, and are axially supported respectively in a state where the distance between the charged shaft 50a and the cleaning shaft 60a is fixed. Two force-applying components 80 are arranged between the bearing part 70 and the housing 41 corresponding to the two bearing parts 70, and the two force-applying components 80 apply force upward to the corresponding bearing parts 70. In this embodiment, the force-applying component 80 is a coil spring with a spring load of 600gf. In this way, since the charged roller 50 and the cleaning roller 60 are axially supported on the bearing part 70 together, the cleaning roller 60 can be stably pressed against the charged roller 50, and a stable cleaning performance can be maintained.

[0057] The bearing portion 70 and the housing 41 may be provided with grooves, protrusions, etc., respectively, so that the direction in which the bearing portion 70 moves may be restricted to the urging direction of the urging member 80 .

[0058] In this embodiment, the photosensitive body shaft 13a of the photosensitive drum 13 is connected to a driving unit (not shown) and rotates by the driving force transmitted. The charging roller 50 is pressed against the photosensitive drum 13 and rotates according to the drive of the photosensitive drum 13 to charge the photosensitive drum 13. The cleaning roller 60 is pressed against the charging roller 50 and rotates according to the rotation of the charging roller 50 to clean the dirt on the charging roller 50.

[0059] Next, refer to Figures 4 to 6B , the relationship between the positions of the photosensitive drum 13 , the charging roller 50 , and the cleaning roller 60 and the direction in which the force is applied by the force applying member 80 will be described.

[0060] Figure 4 This is a schematic side view showing the relationship between the positions and the force application directions of the photosensitive drum, the charging roller, and the cleaning roller.

[0061] Figure 4 The positional relationship among the photosensitive drum 13, the charging roller 50, the cleaning roller 60, and the urging member 80 as viewed from one end side is schematically shown, and the housing 41, the bearing portion 70, etc. are omitted. Figure 4 In the embodiment, the urging member 80 is separated from the charging shaft 50 a and the cleaning shaft 60 a , and the urging force is transmitted to both of them via the bearing portion 70 .

[0062] like Figure 4 As shown, the charging shaft 50a is not located directly below the photosensitive body shaft 13a, but is arranged at a position staggered along the circumferential surface of the photosensitive drum 13 (at Figure 4 In addition, the cleaning shaft 60a is located directly below the charging shaft 50a. Figure 4 The dotted line shown represents the first auxiliary line HL1 passing through the photosensitive body shaft 13a and the charging shaft 50a, and the double-dotted line represents the central axis TL passing through the charging shaft 50a and the cleaning shaft 60a. That is, the photosensitive body shaft 13a is arranged at a position that does not overlap with the central axis TL, and the cleaning shaft 60a is arranged at a position that does not overlap with the first auxiliary line HL1. The force-applying component 80 is configured to be arranged along the central axis TL, and the central axis TL passes through its own center. That is, the force-applying direction of the force-applying component 80 is located on the same straight line as the central axis TL. In this embodiment, the central axis TL and the first auxiliary line HL1 intersect, and the angle between the two (inclination angle θ) is 10 to 15°.

[0063] In the configuration in which the photosensitive drum 13 is charged by the charging roller 50, when the charging roller 50 is deformed in the axis, a difference in the clamping width occurs between the two end portions and the center portion, and the photosensitive body potential sometimes changes. In the present embodiment, the force direction of the force applying member 80 is configured to be inclined relative to the first auxiliary line HL1, thereby suppressing the influence on the clamping width.

[0064] Therefore, regarding the relationship between the position and the force direction of the photosensitive drum 13 and the charging roller 50, refer to the comparative example showing the conventional structure and the embodiment. FIG. 5A to FIG. 6B In addition, FIG. 5A to FIG. 6B In FIG. 1 , the photosensitive drum 13 and the charging roller 50 are focused, and the cleaning roller 60, the force applying member 80, etc. are omitted. Figure 5B and Figure 6B In order to make the change in the shape of the charging roller 50 clear, the bending method of the charging roller 50 is highlighted more than the actual structure.

[0065] 5A is a schematic side view showing the position and force direction of the photosensitive drum and the charging roller in the comparative example, and FIG. 5B is a schematic side view showing Figure 5A Schematic front view of the photosensitive drum and charging roller.

[0066] exist Figure 5A and Figure 5B In the comparative example shown, the charging shaft 50a is located directly below the photosensitive body shaft 13a, and the charging shaft 50a is urged directly upward. That is, the urging force (first urging force F1) from the urging member 80 overlaps the first auxiliary line HL1.

[0067] In the charging roller 50, both end portions in the width direction W are supported by shafts, and the load applied to the charging roller 50 is different from that to the central portion. Figure 5B As shown, deflection occurs along the force application direction. That is, at both ends of the charging roller 50, it contacts the photosensitive drum 13, and at the center, floating occurs between the charging roller 50 and the photosensitive drum 13 according to the amount of deflection. As a result, although the clamping width at both ends in the width direction W is as designed, the clamping width at the center is narrowed, and a difference in the charging potential occurs. The difference in the charging potential affects the amount of toner attached, resulting in changes in image quality, deterioration of cleanability, etc.

[0068] 6A is a schematic side view showing the position and force direction of the photosensitive drum and the charging roller according to the first embodiment of the present invention, and FIG. 6B is a schematic side view showing Fig. 6A Schematic front view of the photosensitive drum and charging roller.

[0069] In the first embodiment of the present invention, as described above, the charging shaft 50a is slightly offset from directly below the photosensitive body shaft 13a, so that the charging shaft 50a is urged directly upward. That is, the urging force (second urging force F2) from the urging member 80 intersects the first auxiliary line HL1.

[0070] In this embodiment, Figure 6B As shown, the charging roller 50 is deflected, but the direction in which the charging axis 50a and the photosensitive body axis 13a face each other (the direction of the first auxiliary line HL1) and the direction in which the deflection occurs (the direction of the second force F2) are offset, so the floating caused by the deflection is reduced.

[0071] As described above, in this embodiment, since the charging roller 50 does not apply force straightly toward the center axis of the photosensitive drum 13, the deviation of the contact position with the photosensitive drum 13 caused by the axial deformation of the charging roller 50 can be alleviated, and the photosensitive drum 13 can be evenly charged without reducing the efficiency of transmitting the pressing force to the charging roller 50.

[0072] exist Figure 4 In FIG. 1 , the force-applying member 80 is shown to apply force in the height direction Z, but the present invention is not limited thereto. The photosensitive body shaft 13a, the charging shaft 50a, and the cleaning shaft 60a can be arranged in such a manner that the central axis TL intersects with the first auxiliary line HL1. That is, the charging shaft 50a can also be located directly below the photosensitive body shaft 13a. In this case, the force-applying member 80 can be configured to apply force in a direction inclined relative to the height direction Z.

[0073] The charging roller 50 and the cleaning roller 60 are preferably arranged below the photosensitive drum 13 in the height direction Z. That is, even if the shaft is deformed downward by its own weight, the charging roller 50 and the cleaning roller 60 are biased upward away from the central axis of the photosensitive drum 13, so that a uniform nip width can be maintained.

[0074] Furthermore, by adopting the crown-shaped charging roller 50, the shaft deformation can be alleviated and the nip width can be made uniform. In addition, the present invention is not limited to this, and the charging roller 50 may also be a straight shape with a uniform diameter.

[0075] Regarding the force applying member 80, Figure 7 As shown in the modified example, the central axis TL can be configured to pass through the side end of the force-applying member 80, and the center of the force applied by the force-applying member 80 and the central axis TL are on the same straight line. That is, if the central axis TL passes through the force-applying member 80 in a manner parallel to the force-applying direction, it can be considered that the force-applying direction of the force-applying member 80 and the central axis TL are on the same straight line. The load from the force-applying member 80 can be adjusted to be applied to the charged shaft 50a and the cleaning shaft 60a through the bearing portion 70.

[0076] (Second Embodiment)

[0077] Next, an image forming apparatus (processing unit) according to a second embodiment of the present invention will be described with reference to the drawings. The configuration of the image forming apparatus according to the second embodiment is substantially the same as that of the first embodiment, and thus the same reference numerals are used and description and drawings are omitted.

[0078] Figure 8 2 is a schematic front view showing a processing unit according to a second embodiment of the present invention. Figure 8 In order to facilitate understanding of the structure of each part, the housing 41, the charging bearing portion 71 and the cleaning bearing portion 72 are shaded.

[0079] In the second embodiment of the present invention, the difference from the first embodiment is that the charged shaft 50a and the cleaning shaft 60a are independently supported. Specifically, in the second embodiment, a charged bearing portion 71 and a cleaning bearing portion 72 are provided to replace the bearing portion 70, and the charged bearing portion 71 supports the two ends of the charged shaft 50a, and the cleaning bearing portion 72 supports the two ends of the cleaning shaft 60a.

[0080] In addition, the force applying member in this embodiment is composed of a charging force applying member 81 for applying force to the charging roller 50 and a cleaning force applying member 82 for applying force to the cleaning roller 60. Specifically, the charging force applying member 81 is arranged between the charging bearing portion 71 and the housing 41, and the cleaning force applying member 82 is arranged between the cleaning bearing portion 72 and the housing 41. In this way, since the charging roller 50 and the cleaning roller 60 are separately applied force, the force and direction applied to them can be freely designed according to the configuration of each part, etc.

[0081] In this embodiment, the urging directions can be made different between the charging urging member 81 and the cleaning urging member 82. Figures 9 to 11 In the second embodiment, the photosensitive drum 13, the charging roller 50 and the cleaning roller 60 are arranged in the same manner as in the first embodiment, and their relationship with respect to the central axis TL and the first auxiliary line HL1 is omitted.

[0082] Fig. 9 It is a schematic side view showing the force application direction of the first arrangement example.

[0083] In the first configuration example, the charging force member 81 and the cleaning force member 82 are both arranged along the central axis TL, and the force direction of the self-force is located on the same straight line as the central axis TL. The charging force member 81 and the cleaning force member 82 are set to have the same force direction, but since the charging roller 50 and the cleaning roller 60 are separately forced, the load on each roller can be appropriately designed.

[0084] Fig.10 It is a schematic side view showing the direction of force in the second arrangement example.

[0085] Fig.10 The dotted line shown represents the second auxiliary line HL2 passing through the photosensitive body shaft 13a and the cleaning shaft 60a. In the second configuration example, the charging force member 81 is arranged along the central axis TL, and the corresponding force direction overlaps with the central axis TL. In addition, the cleaning force member 82 is arranged along the second auxiliary line HL2, and the corresponding force direction overlaps with the second auxiliary line HL2. According to this structure, the cleaning force member 82 is applied to the photosensitive drum 13, and the force from the charging force member 81 is in the direction of deviation from the photosensitive drum 13, so that the influence of the shaft deformation of the charging roller 50 can be alleviated.

[0086] Fig.11 It is a schematic side view showing the force application direction of the third arrangement example.

[0087] In the third configuration example, the charging force member 81 is arranged along the first auxiliary line HL1, and the corresponding force direction overlaps with the first auxiliary line HL1. In addition, the cleaning force member 82 is arranged along the central axis TL, and the corresponding force direction overlaps with the central axis TL. According to this configuration, the force from the cleaning force member 82 applied to the charging roller 50 via the cleaning roller 60 can be applied in a direction to alleviate the deviation of the contact position between the charging roller 50 and the photosensitive drum 13.

[0088] In addition, the embodiments disclosed this time are illustrative in all aspects and are not the basis for restrictive interpretation. Therefore, the technical scope of the present invention is not only interpreted by the above-mentioned embodiments, but is limited based on the records of the claims. In addition, all changes within the meaning and scope equivalent to the claims are included.

[0089] Description of Reference Numerals

[0090] 1 Image forming device

[0091] 13 Photosensitive drum

[0092] 13a Photosensitive body axis (central axis of photosensitive drum)

[0093] 15 with electrical appliances

[0094] 40 processing units

[0095] 41 Shell

[0096] 50 charged roller

[0097] 50a charging shaft (central axis of the charging roller)

[0098] 60 cleaning rollers

[0099] 60a Cleaning shaft (center axis of cleaning roller)

[0100] 70 bearing part

[0101] 71 Live bearing

[0102] 72 Clean the bearing

[0103] 80 force applying parts

[0104] 81 Live force application parts

[0105] 82 Clean the force-applying parts

[0106] TL center axis

[0107] WWidth direction

[0108] Z height direction

Claims

1. A processing unit, which is a processing unit for transferring a toner image, characterized in that: It includes: a photosensitive drum having a toner image formed on its surface; A charging roller, which is pressed against the photosensitive drum and charges the photosensitive drum; a cleaning roller that presses against and cleans the charged roller; A charging force applying component, which applies force to the charging roller; as well as a cleaning force applying member, which applies force to the cleaning roller, The central axis of the photosensitive drum is arranged at a position that does not overlap with a central axis passing through a central axis of the charging roller and a central axis of the cleaning roller. The force application direction of the charged force application component is on the same straight line as the central axis. The cleaning force applying member has a force applying direction on a straight line passing through the central axis of the photosensitive drum and the central axis of the cleaning roller. The cleaning roller is longer than the charging roller in a width direction of the central axis of the photosensitive drum.

2. The processing unit according to claim 1, characterized in that The charging roller and the cleaning roller are arranged below the photosensitive drum in the height direction.

3. The processing unit according to claim 1 or 2, characterized in that: The charging roller is in the shape of a crown.

4. An image forming device, characterized in that: It comprises the processing unit according to any one of claims 1 to 3.

Images