Cartridge and imaging device

Abstract

The present invention relates to a box and an imaging device. The box for the imaging device includes: a processing unit to be used for forming an image; a first component containing a first resin material; a second component containing a second resin material with higher flame retardancy than the first resin material; and an electrode component, which includes a contact portion configured to supply power from a device body of the imaging device. The electrode component is configured to electrically connect the device body to the processing unit. The second resin material of the second component has a greater density than the first resin material of the first component. The contact portion is located near the first component and the second component and is closer to the second component than to the first component.

Description

Technical Field

[0001] The present invention relates to a cartridge and an image forming apparatus using the cartridge. Background Art

[0002] In an electrophotographic image forming apparatus using a process cartridge system, when the cartridge is attached to the apparatus body, an electrode component of the cartridge contacts a main body electrode of the apparatus body, thereby electrically connecting a conductive target component (e.g., a process unit) of the cartridge to the apparatus body. As an example of an electrode component, Japanese Patent Application Publication No. 2012-63750 discloses a configuration in which a conductive resin is contained in a frame of a cartridge. Summary of the invention

[0003] However, in the above conventional example, since the conductive part (which may be, for example, a conductive resin or a metal plate) is attached to the frame, the frame needs to be made of a resin (flame retardant material) having a high flame retardant function to ensure electrical safety near the conductive part. The use of flame retardant materials limits the choice of materials. This poses a challenge to weight reduction of the frame member in particular.

[0004] An object of the present invention is to provide a technique for simultaneously achieving weight reduction and safety of a frame for supporting a processing unit.

[0005] In order to solve the above problems, a cartridge for an imaging device includes:

[0006] a processing unit to be used to form an image;

[0007] a first component comprising a first resin material;

[0008] A second member including a second resin material having higher flame retardancy than the first resin material; and

[0009] an electrode member including a contact portion configured to supply power from a device body of the imaging device, the electrode member being configured to electrically connect the device body to the processing unit, wherein

[0010] the second resin material of the second component has a greater density than the first resin material of the first component, and

[0011] The contact portion is located adjacent to the first component and the second component and is closer to the second component than to the first component.

[0012] In order to solve the above problems, a cartridge for an imaging device includes:

[0013] a processing unit to be used to form an image;

[0014] a first component comprising a first resin material;

[0015] A second member including a second resin material having higher flame retardancy than the first resin material; and

[0016] an electrode member including a contact portion configured to supply power from a device body of the imaging device, the electrode member being configured to electrically connect the device body to the processing unit, wherein

[0017] the second resin material of the second component has a greater density than the first resin material of the first component, and

[0018] The contact portion is located in the second component.

[0019] In order to solve the above problems, a cartridge for an imaging device includes:

[0020] a processing unit to be used to form an image;

[0021] a first component comprising a first resin material;

[0022] A second member including a second resin material having higher flame retardancy than the first resin material; and

[0023] an electrode member including a contact portion configured to supply power from a device body of the imaging device, the electrode member being configured to electrically connect the device body to the processing unit, wherein

[0024] the second resin material of the second component has a greater density than the first resin material of the first component, and

[0025] The second component is positioned so that in the event that power supply from the device body to the electrode component causes the contact portion to become a source of ignition, the second component self-extinguishes without igniting the first component.

[0026] According to the present invention, it is possible to simultaneously achieve weight reduction and safety of a frame supporting a processing unit.

[0027] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is an exploded view of the developing contact structure according to the first embodiment;

[0029] Figure 2 is a sectional view of the imaging device main body and the cartridge of the first embodiment;

[0030] Figure 3 is a cross-sectional view of the box of the first embodiment;

[0031] Figure 4 is a perspective view showing the configuration of the cartridge of the first embodiment;

[0032] Figure 5 is a perspective view showing the configuration of a cleaning unit of the first embodiment;

[0033] Fig. 6A and 6B is a sectional view for illustrating attachment of the cartridge of the first embodiment;

[0034] Fig. 7A and 7B is a sectional view for illustrating the positioning of the cartridge of the first embodiment;

[0035] Figures 8A to 8D is a perspective view for illustrating attachment and detachment of the cartridge of the first embodiment;

[0036] Fig. 9 is a perspective view showing the configuration of the cartridge of the first embodiment;

[0037] Fig.10 is an exploded perspective view showing the configuration of charging contacts of the cartridge of the first embodiment;

[0038] Fig.11A and 11B 1 is a diagram showing a developing contact structure of a cartridge of the first embodiment;

[0039] Fig. 12A and 12B is a diagram showing the configuration of charging contacts of the cartridge of the first embodiment;

[0040] Figures 13A to 13D is a diagram showing a conductive bearing component of a first embodiment;

[0041] Fig.14 is an enlarged view showing a conductive portion of the first embodiment;

[0042] Fig.15 is an exploded perspective view of a developing unit of the second embodiment;

[0043] Fig.16 is a schematic diagram of an imaging device according to a second embodiment;

[0044] Fig.17 is a cross-sectional view of a box of a second embodiment;

[0045] Fig.18A and 18B is a perspective view of a box of a second embodiment;

[0046] Fig.19 is a perspective view of a developing unit of a second embodiment;

[0047] Fig. 20A is a side view of a developing unit of the second embodiment;

[0048] Fig. 20Bis an enlarged sectional view of a developing unit of the second embodiment;

[0049] Fig.21 is an exploded perspective view of a cleaning unit of the second embodiment;

[0050] Fig.22A is a side view of a cleaning unit of the second embodiment;

[0051] Fig. 22B is an enlarged cross-sectional view of a cleaning unit of the second embodiment;

[0052] Fig.23 is a schematic cross-sectional view of an imaging device of a third embodiment;

[0053] Fig.24 is a cross-sectional view of a box of a third embodiment;

[0054] Fig.25 is a sectional view of an imaging device according to a third embodiment;

[0055] Fig.26 is a sectional view of an imaging device according to a third embodiment;

[0056] Fig. 27 is a sectional view of an imaging device according to a third embodiment;

[0057] Fig.28 is an exploded perspective view of a drum unit of a third embodiment;

[0058] Fig.29 is an exploded perspective view of a developing unit of a third embodiment;

[0059] Fig.30 is an exploded perspective view of a cartridge of a third embodiment;

[0060] Fig.31 is an assembled perspective view of a box of a third embodiment;

[0061] Fig.32A is a perspective view of a cartridge and a non-drive side cartridge cover member of a third embodiment;

[0062] Fig.32B is a sectional view of a non-driving side cover member of a third embodiment;

[0063] Fig.32C is a sectional view of a cartridge and a non-driving side cartridge cover member of a third embodiment;

[0064] Fig.32D is a sectional view of a cartridge and a non-driving side cartridge cover member of a third embodiment;

[0065] Fig.33A is a perspective view showing a storage element communication unit and a contact spring holding member of a third embodiment;

[0066] Fig.33B is an enlarged view showing a storage element communication unit and a contact spring holding member of the third embodiment; and

[0067] Fig.33C It is an enlarged view showing the storage element communication unit and the contact spring holding member of the third embodiment.

[0068] Fig.34A 1 is a perspective view showing a cleaning frame main body portion extracted separately as a key component of a charging contact configuration of a modification of Embodiment 1. FIG.

[0069] Fig.34B 1 is a perspective view showing key parts of a charging contact configuration extracted in a state where a contact cover portion is formed in a cleaning frame main body portion by two-color molding according to a modification of Embodiment 1.

[0070] Fig.35 1 is an exploded perspective view showing key components of a charging contact configuration extracted from a modification of Embodiment 1.

[0071] Fig.36A 1 is a side view for illustrating a charging contact structure of a modification of the first embodiment.

[0072] Fig.36B is along Fig.36A An enlarged cross-sectional view of the charging contact taken along line HH in FIG. DETAILED DESCRIPTION

[0073] Hereinafter, embodiments (examples) of the present invention will be described with reference to the accompanying drawings. However, the size, material, shape, and relative arrangement of the constituent elements described in each embodiment may be appropriately changed according to the configuration of the device to which the present invention is applied, various conditions, etc. Therefore, the size, material, shape, and relative arrangement of the constituent elements described in each embodiment are not intended to limit the scope of the present invention to the following embodiments.

[0074] First embodiment

[0075] With reference to the accompanying drawings, embodiments of the present invention will now be described in detail. The direction along the rotation axis of the electrophotographic photosensitive drum is referred to as the longitudinal direction. In the longitudinal direction, the side of the electrophotographic photosensitive drum receiving the driving force from the image forming device body is referred to as the driving side, and the opposite side is referred to as the non-driving side. Figure 2 and 3 , the overall construction and imaging process are now described. Figure 2 1 is a sectional view of an apparatus main body (electrophotographic image forming apparatus main body, image forming apparatus main body) A and a process cartridge B of an electrophotographic image forming apparatus according to an embodiment of the present invention. Figure 3is a cross-sectional view of a process box B. The process box is formed by integrating a photosensitive component and a process unit acting on the photosensitive component into a box. The process box is attached to the main body of the electrophotographic imaging device in a detachable manner. For example, the process box can be formed by integrating at least one of a developing unit, a charging unit, and a cleaning unit as a process unit with a photosensitive component into a box. The electrophotographic imaging device forms an image on a recording medium using an electrophotographic imaging method. Examples of electrophotographic imaging devices include electrophotographic copiers, electrophotographic printers (e.g., LED printers and laser beam printers), fax machines, and word processors. The device body A is a portion of the electrophotographic imaging device that does not include a process box B (hereinafter referred to as box B).

[0076] Overall structure of electronic photographic imaging device

[0077] Figure 2 The electrophotographic imaging device (imaging device) shown is a laser beam printer using electrophotographic technology, in which a cartridge B is attached to a device body A in a detachable manner. When cartridge B has been attached to the device body A, an exposure device 3 (laser scanner unit) is arranged to form a latent image on an electrophotographic photosensitive drum 62 (as an image bearing member of cartridge B). A sheet tray 4 arranged below cartridge B stores a recording medium (hereinafter referred to as sheet material PA) on which an image is to be formed. The electrophotographic photosensitive drum 62 is a photosensitive member (electrophotographic photosensitive member) for forming an electrophotographic image. The device body A also includes a pickup roller 5a, a pair of feed rollers 5b, a transfer guide 6, a transfer roller 7, a conveying guide 8, a fixing device 9, a pair of discharge rollers 10, and a discharge tray 11 arranged along a conveying direction D of the sheet material PA. The fixing device 9 includes a heating roller 9a and a pressing roller 9b.

[0078] Imaging process

[0079] The outline of the image forming process will now be described. In response to a print start signal, an electrophotographic photosensitive drum (hereinafter, referred to as a photosensitive drum 62 or simply referred to as a drum 62) is driven to rotate at a predetermined peripheral speed (process speed) in the direction of arrow R. A charging roller (charging member) 66 to which a bias voltage is applied contacts the outer peripheral surface of the drum 62 and uniformly charges the outer peripheral surface of the drum 62 (see FIG. 1 ). Figure 3 The exposure device 3 outputs a laser beam L according to the image information. The laser beam L passes through a laser opening 71h provided in a cleaning frame 71 of the cartridge B (see Figure 2 ), and scans the peripheral surface of the drum 62 to perform exposure. In this way, an electrostatic latent image corresponding to the image information is formed on the peripheral surface of the drum 62.

[0080] like Figure 3As shown, the developing unit 20 as a developing device includes a toner chamber 29 storing toner T. A conveying member (stirring member) 43 rotates to stir the toner T and convey the toner T to the toner supply chamber 28. The magnetic force of the magnetic roller 34 (fixed magnet) holds the toner T on the surface of the developing roller 32. The developing roller 32 is a developer carrying member that carries the developer (toner T) on its surface for developing the latent image formed on the drum 62. The developing blade 42 frictionally charges the toner T and controls the layer thickness of the toner T on the outer peripheral surface of the developing roller 32 as the developer carrying member.

[0081] The toner T is supplied to the drum 62 according to the electrostatic latent image and develops the latent image. As a result, the latent image is formed into a visible toner image. The drum 62 is an image bearing member that carries a latent image or an image to be formed with toner (toner image, developer image) on its surface. Figure 2 As shown, the sheet material PA stored in the lower part of the apparatus body A is sent out from the sheet tray 4 by the pickup roller 5a and the pair of feed rollers 5b in a timely manner according to the timing of the output of the laser beam L. The sheet material PA is conveyed along the transfer guide 6 to a transfer position between the drum 62 and the transfer roller 7. At the transfer position, the toner image is sequentially transferred from the drum 62 to the sheet material PA.

[0082] The sheet material PA to which the toner image is transferred is conveyed away from the drum 62 and conveyed to the fixing device 9 along the conveying guide 8. Then, the sheet material PA passes through the nip portion between the heating roller 9a and the pressing roller 9b of the fixing device 9. The fixing process of pressing and heating at the nip portion fixes the toner image to the sheet material PA. The sheet material PA subjected to the toner image fixing process is conveyed to the pair of discharge rollers 10 and discharged to the discharge tray 11.

[0083] like Figure 3 As shown, the residual toner remaining on the outer peripheral surface of the drum 62 after the transfer is removed by the cleaning member 77 and is used again in the image forming process. The toner removed from the drum 62 is stored in the waste toner chamber 71b of the toner cleaning unit 60. The cleaning unit 60 is a photosensitive drum unit including the photosensitive drum 62. In the foregoing description, the charging roller 66, the developing roller 32, the transfer roller 7 and the cleaning member 77 act as a process unit acting on the drum 62.

[0084] Overall box construction

[0085] Reference Figure 3 , 4 and 5, the overall structure of box B is now described. Figure 3 is a cross-sectional view of box B, Figure 4 and 51 is a perspective view showing the structure of the box B. In this embodiment, the description of the screws for connecting the components is omitted. The box B includes a cleaning unit (photosensitive component holding unit, drum holding unit, image bearing component holding unit, first unit) 60 and a developing unit (developer bearing component holding unit, second unit) 20.

[0086] like Figure 3 As shown, the cleaning unit 60 includes a drum 62, a charging roller 66, a cleaning member 77, and a cleaning frame 71 that supports these members. On the driving side, the drum 62 includes a driving side drum flange 63 rotatably supported by a hole portion 73a of a drum bearing 73 (see FIG. Figure 4 ). In a broad sense, the drum bearing 73 and the cleaning frame 71 may be collectively referred to as a cleaning frame. Figure 5 As shown, on the non-driving side, the drum shaft 78 is press-fitted into a hole portion 71c formed in the cleaning frame 71 so as to rotatably support a hole portion (not shown) of the non-driving side drum flange.

[0087] The drum flange is the portion that is rotatably carried and supported by the respective bearing portion. Figure 3 As shown, the charging roller 66 and the cleaning member 77 of the cleaning unit 60 are in contact with the outer peripheral surface of the drum 62. The cleaning member 77 has a rubber scraper 77a and a supporting member 77b that supports the rubber scraper, and the rubber scraper 77a is a scraper-shaped elastic member made of rubber as an elastic material. The rubber scraper 77a extends substantially in a direction opposite to the rotation direction of the drum 62 and contacts the drum 62. That is, the rubber scraper 77a contacts the drum 62 in a manner that its distal edge points to the upstream side in the rotation direction R of the drum 62. The waste toner removed from the surface of the drum 62 by the cleaning member 77 is stored in a waste toner chamber 71b defined by the cleaning frame 71 and the cleaning member 77.

[0088] like Figure 3 As shown, a shovel blade 65 for preventing waste toner from leaking from the cleaning frame 71 is provided at the edge of the cleaning frame 71 in contact with the drum 62. The charging roller 66 is rotatably attached to the cleaning unit 60 through charging roller bearings 67 located at opposite ends in the longitudinal direction of the cleaning frame 71. The longitudinal direction of the cleaning frame 71 (the longitudinal direction of the box B) is substantially parallel to the direction (axial direction) in which the axis of rotation of the drum 62 extends. Therefore, hereinafter, unless otherwise specified, the longitudinal direction and the axial direction both refer to the axial direction of the drum 62. The pushing member 68 presses the charging roller bearing 67 toward the drum 62, thereby pressing the charging roller 66 against the drum 62. The charging roller 66 is driven and rotated by the rotation of the drum 62.

[0089] like Figure 3As shown, the developing unit 20 includes a developing roller 32, a developer container 23 supporting the developing roller 32, and a developing blade 42. The developing roller 32 is supported by bearing members 26 ( Figure 4 ) and 27( Figure 5 ) is rotatably attached to the developer container 23. The developing roller 32 includes a magnetic roller 34. The developing unit 20 includes a developing blade 42 for controlling the toner layer on the developing roller 32. Figure 4 and 5 As shown, the spacer members 38 are attached to opposite ends of the developing roller 32. The spacer members 38 are in contact with the drum 62, thereby holding the developing roller 32 in a manner that creates a small gap between the developing roller 32 and the drum 62. Figure 3 As shown, a spray-out prevention sheet 33 for preventing toner from leaking from the developing unit 20 is provided at the edge of the developer container 23 and contacts the developing roller 32. A conveying member 43 is provided in the toner chamber 29 defined by the developer container 23 and the base member 22. The conveying member 43 agitates the toner stored in the toner chamber 29 and conveys the toner to the toner supply chamber 28.

[0090] like Figure 4 and 5 As shown, box B is formed by combining the cleaning unit 60 and the developing unit 20. In order to combine the developing unit 20 to the cleaning unit 60, the center of the first developing side supporting boss 26a of the bearing component 26 is aligned with the first suspension hole 71i of the driving side of the cleaning frame 71, and the center of the second developing side supporting boss 27a of the bearing component 27 is aligned with the second suspension hole 71j of the non-driving side. Specifically, the developing unit 20 moves in the direction of arrow G so that the first and second developing side supporting bosses 26a and 27a are assembled into the first and second suspension holes 71i and 71j. In this way, the developing unit 20 is movably connected to the cleaning unit 60. Specifically, the developing unit 20 is rotationally (pivotally) connected to the cleaning unit 60. That is, the developing roller 32 is connected to the drum 62 in a manner that it can move toward and away from the drum 62. Then, the drum bearing 73 is connected to the cleaning unit 60 to form box B.

[0091] In this embodiment, the non-driving side pressing member 46L ( Figure 5 ) and the driving side pressing member 46R ( Figure 4) is a compression spring. The urging force of the spring causes the driving side urging member 46R and the non-driving side urging member 46L to urge the developing unit 20 toward the cleaning unit 60 to ensure that the developing roller 32 is pressed in the direction of the drum 62. The present embodiment further includes a spacing member 38 located at opposite ends of the developing roller 32. That is, the drum 62 contacts the developing roller 32 with a predetermined contact pressure across the spacing member 38, thereby holding the developing roller 32 in a manner that a predetermined gap is generated between the developing roller 32 and the drum 62. The relative positions of these components are thus determined.

[0092] Attachment of box

[0093] Reference Fig. 6A , 6B , 7A and 7B, the attachment of box B will now be described in detail. Fig. 6A is a sectional view of a driving side guide portion of the image forming apparatus A, for illustrating attachment of the cartridge B. Figure 6B is a sectional view of the non-driving side guide portion of the image forming apparatus A, for illustrating the attachment of the cartridge B. Fig. 7A It is a sectional view of the driving side of the image forming apparatus A, for illustrating the positioning of the cartridge B. Figure 7B It is a sectional view of the non-driving side of the image forming apparatus A, for illustrating the positioning of the cartridge B.

[0094] Box B is attached as follows. Fig. 6A and 6B As shown, the first drive side plate 15 includes an upper guide rail 15g and a guide rail 15h as guides, and the non-drive side plate 16 includes an upper guide rail 16d and a guide rail 16e. The drum bearing 73 provided on the drive side of the box B has a rotation stop target portion 73c. ​​The box B is arranged along a substantially perpendicular direction to the drum 62 ( Figure 3 ) is attached in the direction of the axis (arrow C).

[0095] The non-driving side of cleaning frame 71 in the longitudinal direction comprises a positioning target portion 71d as the first positioning portion and a rotation stop target portion 71f as the second positioning portion. When box B is attached by the box insertion slot 17 of device body A, the guide rail 15h of device body A at the driving side of box B guides the rotation stop target portion 73c of box B. At the non-driving side of box B, the guide rails 16d and 16e of device body A guide the positioning target portion 71d and the rotation stop target portion 71f of box B. Box B is attached to device body A like this.

[0096] The closing of the opening / closing door 13 will now be described. Fig. 6A , 6B, 7A and 7B, the first drive side plate 15 has an upper positioning portion 15a, a lower positioning portion 15b and a rotation stop portion 15c as positioning portions, and the non-drive side plate 16 has a positioning portion 16a and an upper rotation stop portion 16c. The drum bearing 73 includes an upper positioning target portion (a first positioning target portion, a first protrusion, a first raised portion) 73d and a lower positioning target portion (a second positioning target portion, a second protrusion, a second raised portion) 73f.

[0097] The cartridge pressing members 1 and 2 are rotatably attached to opposite axial ends of the opening / closing door 13. The cartridge pressing springs 19 and 21 are attached to longitudinal ends of the front plate of the image forming apparatus A. The drum bearing 73 has a pressing target portion 73e as a pushing force receiving portion, and the cleaning frame 71 (see Figure 3 ) has a pressing target portion 71o on the non-driving side. When the opening / closing door 13 is closed, the cartridge pressing members 1 and 2 pushed by the cartridge pressing springs 19 and 21 of the apparatus body A press the pressing target portions 73e and 71o of the cartridge B (see Fig. 7A and 7B ).

[0098] As a result, on the driving side, the upper positioning target portion 73d, the lower positioning target portion 73f and the rotation stop target portion 73c of box B are fixed to the upper positioning portion 15a, the lower positioning portion 15b and the rotation stop portion 15c of the device body A respectively. Like this, box B and drum 62 are positioned on the driving side. Similarly, on the non-driving side, the positioning target portion 71d and the rotation stop target portion 71f of box B are fixed to the positioning portion 16a and the rotation stop portion 16c of the device body A respectively. Like this, box B and drum 62 are positioned on the non-driving side.

[0099] The above description of the example of the configuration for positioning the cartridge B relative to the apparatus body A is not intended to limit the means for positioning. A configuration that directly acts on the positioning target portion 73d and the rotation stop target portion 73f on the drive side of the cartridge B and the positioning target portion 71d and the rotation stop target portion 71f on the non-drive side to fix the respective positioning portions may be used.

[0100] Reference Fig. 8A , 8B , 8C and 8D, now describe the structure of box B receiving driving force from the device body A. Fig. 8A 2 is a diagram showing the structure of the driving portion of the device body A. Figure 8B 2 is a diagram showing the configuration of a driving portion of box B. Figure 8C 1 is a diagram showing a state before the driving portion of the apparatus body A and the driving portion of the cartridge B are engaged. Fig.8D 1 and 2 are diagrams showing a state in which the power of the apparatus body A is turned on and the driving portion of the apparatus body A and the driving portion of the cartridge B are engaged.

[0101] like Fig. 8A As shown, the device body A includes a drive transmission member 81 that receives a driving force from a driving source (not shown) of the device body A and transmits the driving force to the cartridge B. Figure 8B As shown, the cartridge B includes a driven portion 63b located in the driving side drum flange 63 to engage with the drive transmission member 81 and receive the driving force. When the opening / closing door 13 is closed and the power of the device body A is turned on, the drive transmission member 81 is in Figure 8C Move in the direction of arrow E in the figure. Then, Fig.8D As shown in FIG. 1 , the drive transmission portion 81b of the drive transmission member 81 is engaged with the driven portion 63b of the drive side drum flange 63, and the drum 62 is rotated by the drive side drum flange 63. The outer periphery of the drive transmission member 81 is in the shape of a gear 81g. In addition, the developing roller gear 90 is connected to the end of the developing roller 32 of the cartridge B. When the driven portion 63b of the drive side drum flange 63 is engaged as shown in FIG. Fig.8D When the drive transmission member 81 is engaged, the gear shape 81g on the drive transmission member 81 and the developing roller gear 90 are arranged to mesh with each other. That is, when the drive transmission member 81 rotates the drum 62 through the driving side drum flange, the developing drum 32 is also rotated simultaneously through the developing roller gear 90.

[0102] Development contact structure

[0103] Reference Figure 1 , 9 , 11A and 11B, the developing contact structure of box B is now described, which is a feature of this embodiment. Figure 1 2 is an exploded perspective view of the developing unit 20, showing key components of the developing contact structure extracted. Fig. 9 is a perspective view of box B, Fig.11A is a side view of the cartridge B for illustrating the structure of the developing contact, Fig. 11B is along Fig.11A An enlarged cross-sectional view of the area around the developing contact taken along line II in FIG.

[0104] like Figure 1 As shown, the developing unit 20 includes a developer container 23 as a first frame (first member) and a developing roller 32 as a process unit. The developer container 23 is made of a material having a density of about 0.95 to 1.10 g / cm 3And it is made of a material (first resin material) with a flame retardant property of HB according to the UL94 standard. It is well known that adding additives to a resin material (which generally has the property of being ignited when in contact with fire) can make the resin have flame retardant properties. When an additive is added to a resin material, a higher flame retardant effect results in a greater specific gravity of the resin. This causes the problem of increasing the weight of the resin material necessary in the entire product, thereby placing a greater burden on the environment. In this embodiment, the developer container 23 is made of a material that does not contain such an additive and has a low density. The developing roller 32 has a function of carrying the developer by receiving a predetermined bias voltage. The developing roller 32 is connected to the developing roller 32 by a bearing component 26 on the driving side (see Figure 4 ) and the conductive bearing member 937 and the bearing member 27 on the non-driving side are rotatably supported by the developer container 23 as a rotating member.

[0105] Flame retardant properties are now described. In the present embodiment, UL94 standards are used to evaluate flame retardant properties. In order to evaluate the flame retardant properties of resins (e.g., plastics), it is first necessary to determine whether the material is self-extinguishing. The combustion test according to the UL94 standard generally includes horizontal combustion tests on non-self-extinguishing resin materials and vertical combustion tests on self-extinguishing resin materials. Examples of resin materials for horizontal combustion tests include HB materials. Examples of resin materials for vertical combustion tests include 5VA, 5VB, V-0, V-1, and V-2 materials. As a criterion for the grade according to the UL94 standard, the material that passes the horizontal combustion test on the HB material needs to show slow burning characteristics even if it is not self-extinguishing and the burning speed is 40mm / min or less when the thickness of the test sample is more than 3mm. As for the vertical combustion test, the V-0 material needs to have a burning time of less than 10 seconds when the flame is applied to the test sample twice for 10 seconds each time, and the V-1 and V-2 materials need to have a burning time of less than 30 seconds when the flame is applied to the test sample twice for 10 seconds each time. Here, the shorter the burning time, the harder it is to burn. That is, the "high flame retardant performance" in this embodiment not only means the difference in flame retardant grade, but also means that the burning time is shorter in the same burning test.

[0106] In addition to the UL94 standard, the oxygen index according to the JIS standard can also be used. The oxygen index is an index that indicates the minimum oxygen concentration percentage required for the ignited resin material to maintain combustion. The larger the oxygen index, the stronger the flame retardant performance. For example, the oxygen index of HB material is about 15 to 19, the oxygen index of V-2 material is about 24 to 25, the oxygen index of V-1 material is about 25 to 29, and the oxygen index of V-0 material is about 29 or more.

[0107] like Figure 1 , 11AAs shown in FIG. 11B , the conductive bearing member 937 includes a spring contact 1751, which is a power supply member of the image forming apparatus and is used to apply a predetermined bias voltage to the developing roller 32, and a conductive portion 1701, which is an electrode member made of a conductive resin. The spring contact 1751 and the conductive portion 1701 form a conductive path between the apparatus body and the developing roller 32.

[0108] like Figure 1 As shown, the conductive bearing component 937 includes a conductive portion 1701 and a non-conductive portion 1702 formed integrally, and the non-conductive portion 1702 serves as a second frame (second component). The non-conductive portion 1702 is made of a material having a density of about 1.12 to 1.50 g / cm 3 And it is made of a material (second resin material) with a flame retardancy of V-1 according to the UL94 standard, that is, it has a higher flame retardancy than the developer container 23. Fig.11A and 11B As shown, the conductive portion 1701 includes a contact portion 1701a exposed outward to contact a spring contact 1751 (which serves as a power supply component of the image forming apparatus) to receive power, and a conductive support portion 1701b as a shaft support portion that rotatably supports the developing roller 32.

[0109] Figures 13A to 13D 937 is a diagram for illustrating the details of the conductive bearing member 937. Fig. 13B and 13C is an exploded view in which the conductive portion 1701 and the non-conductive portion 1702 are displaced in the longitudinal direction. Fig. 13B and 13C The conductive portion 1701 and the non-conductive portion 1702 are shown to be arranged side by side in the longitudinal direction, but these portions are not configured to be integrated by being assembled to each other in the longitudinal direction. In the present embodiment, the conductive portion 1701 and the non-conductive portion 1702 are formed by two-color molding, and the conductive portion 1701 has a portion formed to be expanded at one side in the longitudinal direction of the non-conductive portion 1702, and a portion formed to be expanded at the other side. For example, the contact portion 1701a and the conductive support portion 1701b are portions of the conductive portion 1701 formed at opposite sides in the longitudinal direction of the non-conductive portion 1702. That is, Fig. 13B and 13C 17 is a phantom diagram showing that the conductive portion 1701 and the non-conductive portion 1702 are shifted in the longitudinal direction to clarify their configuration (particularly, the configuration portion that is not visible from the outside when these portions are integrated together). Fig.13A A state in which the conductive portion 1701 and the non-conductive portion 1702 are integrated together is shown.

[0110] like Fig. 13CAs shown, the non-conductive portion 1702 has an electrode seating surface 1702c that is opposite to the contact portion 1701a in the longitudinal direction and extends in a direction perpendicular to the longitudinal direction.

[0111] The contact portion 1701a of the conductive portion 1701 is closer to the non-conductive portion 1702 than to the developer container 23, and is in contact with the non-conductive portion 1702. For example, if an event such as an abnormality in the high-voltage power supply of the device body A causes discharge between the contact portion 1701a and the spring contact 1751 as the power supply portion, this may produce an electrical ignition source. In this regard, the non-conductive portion 1702 in contact with the contact portion 1701a of the present construction has high flame retardant properties. If any fire that occurs in the contact portion 1701a is about to spread to the non-conductive portion 1702, the non-conductive portion 1702 generates non-flammable gas from the inside of its material and carbonizes the resin surface to prevent the fire from spreading to the inside of the resin, thereby helping self-extinguishing. As a result, even if the contact portion 1701a of the conductive portion 1701 is located near the developer container 23, the fire can be prevented from spreading to the developer container 23 because the contact portion 1701a is closer to the non-conductive portion 1702 than to the developer container 23. The term "nearby" used herein refers to a range of influence of ignition from an electric ignition source caused by discharge occurring between the power supply portion and the contact portion due to an abnormal situation or the like.

[0112] That is, in the cartridge B of the present embodiment, the developer container 23 is made of HB material which is a low-density resin material to reduce the overall weight of the product, while a highly flame-retardant V-1 material is used near the connecting portion (which serves as a conductive path) between the device body A and the cartridge B. This provides a cartridge B that achieves both safety and weight reduction of the entire product.

[0113] Furthermore, the bearing member 27 as a third frame (third member) holds the conductive bearing member 937 and is fixed to the developer container 23. The bearing member 27 is made of a material having a density of about 1.12 to 1.50 g / cm 3 And it is made of materials with flame retardancy of V-1 according to UL94 standard. Fig. 11B As shown, the bearing member 27 is adjacent to the conductive portion 1701 and has a protruding portion 27a that protrudes beyond the electrode placement surface 1702c of the non-conductive portion 1702 in the longitudinal direction W (see Fig. 13C). That is, the bearing component 27 has a protruding portion 27a formed to shield the electrode placement surface 1702c of the non-conductive portion 1702 from the outside. For example, an abnormality in the high-voltage power supply of the device body A or other factors may cause discharge between the spring contact 1751 as the power supply part and the contact portion 1701a of the conductive portion 1701, thereby causing electric ignition. At this time, even if a fire occurs in the area from the contact portion 1701a of the conductive portion 1701 to the electrode placement surface 1702c of the non-conductive portion 1702 along the longitudinal direction W, the protruding portion 27a confines the non-flammable gas generated from the non-conductive portion 1702 and the bearing component 27. This further promotes the self-extinguishing of the non-conductive portion 1702, so that the spread of fire can be prevented at the electrode placement surface 1702c. Therefore, safety can be further improved.

[0114] In terms of confining non-combustible gases and suppressing the spread of fire, the protrusion 27a is preferably constructed to protrude in a manner that completely surrounds the periphery (periphery) of the electrode mounting surface 1702c. However, the protrusion 27a can have any of a variety of structures as long as it can provide a certain effect. Since fire tends to spread upward in the vertical direction, the effect of preventing the spread of fire can be achieved by arranging the protrusion 27a above the electrode mounting surface 1702c at least in the vertical direction to block the space between the electrode mounting surface 1702c and the developer container 23 (which is the first frame). That is, the protrusion of the present invention can play a role in suppressing the spread of fire when a fire occurs, as long as the protrusion has at least a portion extending above the contact portion in the vertical direction. It should be obvious that this also applies to the construction of other protrusions described below.

[0115] Figures 13A to 13D 937 is a perspective view for illustrating the structure of the conductive bearing member 937 in detail. Fig.13A A conductive bearing component 937 is shown in which a conductive portion 1701 and a non-conductive portion 1702 are integrally molded. Fig. 13B and 13C 937 is a phantom diagram showing the conductive portion 1701 and the non-conductive portion 1702 of the conductive bearing member 937 being displaced in the longitudinal direction for illustrative purposes.

[0116] like Fig. 13B As shown, the conductive portion 1701 and the non-conductive portion 1702 of the conductive bearing member 937 are made of different resin materials and are integrally formed. The conductive portion 1701 has a conductive support portion 1701b that supports the inner peripheral portion of the developing roller 32 (which is a rotating member). Fig.13A The cross section Fig.13D, the non-conductive portion 1702 has an inner peripheral support portion 1702a and an outer peripheral support portion 1702b for supporting the conductive portion 1701. The inner peripheral support portion 1702a and the outer peripheral support portion 1702b support the cylindrical conductive support portion 1701b of the conductive portion 1701 in a manner of sandwiching from the inner peripheral side and the outer peripheral side. This restricts the conductive support portion 1701b from tilting relative to the non-conductive portion 1702 even when a gap is generated between the conductive portion 1701 and the non-conductive portion 1702 due to the difference in thermal expansion rate of the materials. Therefore, the developing roller 32 can rotate stably.

[0117] Fig.14 1701 is an enlarged view for showing the configuration of the conductive portion 1701 in detail. The conductive portion 1701 includes a connecting portion 1701e for connecting the contact portion 1701a and the conductive support portion 1701b. As described above, the conductive portion 1701 and the non-conductive portion 1702 are formed by two-color molding, and the conductive portion 1701 has a portion formed by a resin that is expanded at one side in the longitudinal direction of the non-conductive portion 1702 when molded, and a portion formed by a resin that is expanded at the other side in the longitudinal direction of the non-conductive portion 1702 when molded. The connecting portion 1701e is a portion that connects a portion formed to be expanded at one side in the longitudinal direction of the non-conductive portion 1702 (which is the contact portion 1701a) and a portion formed to be expanded at the other side (which is the conductive support portion 1701b). In the two-color molding of the conductive portion 1701, the resin is injected into the mold cavity through the gate portion 1701c as an injection port in the order of the contact portion 1701a, the connection portion 1701e and the conductive support portion 1701b. In this configuration, when viewed from a direction perpendicular to the plane including the contact portion 1701a, the conductive portion 1701 is formed so that the gate portion 1701c and the connection portion 1701e overlap with the contact portion 1701a (overlap and are included in the contact portion 1701a). In addition, when viewed from the same direction, the contact portion 1701a and the conductive support portion 1701b partially overlap each other. That is, the resin injection path from the gate portion 1701c to the conductive support portion 1701b is shorter than, for example, a configuration in which the injection path bypasses the non-conductive portion 1702 and extends outside the non-conductive portion 1702. This reduces the amount of resin material used to form the conductive portion 1701. Therefore, in the event of any fire occurring in the contact portion 1701a, the spread of the fire along the conductive resin can be reduced, thereby increasing the safety of the contact structure.

[0118] In the present embodiment, polystyrene (PS) is used for the developer container 23 as the first frame. A mixed resin of polycarbonate and acrylonitrile-butadiene-styrene (PC-ABS) is used for the non-conductive portion 1702 as the second frame and the bearing member 27 as the third frame. Conductive polyacetal (POM) is used for the conductive portion 1701 as the resin electrode member. However, these materials are not limited to the materials of the present embodiment.

[0119] Charging contact structure

[0120] Reference Fig.10 , 12A and 12B, the charging contact configuration which is a feature of the present embodiment will now be described in detail. Fig.10 is an exploded perspective view showing key components of the charging contact configuration extracted. Fig. 12A It is a side view for showing the configuration of the charging contact. Fig. 12B is along Fig. 12A An enlarged cross-sectional view of the charging contact taken along line GG in FIG.

[0121] like Fig.10 As shown, the cleaning unit 60 has a cleaning frame 71 as a first frame. Figure 3 As shown in FIG. 1 , the charging roller 66 as a process unit is disposed in the cleaning frame 71. Fig.10 As shown, an electrode plate 82 for electrically connecting the charging roller 66 to the apparatus body is attached to the side surface of the non-driving side of the cleaning frame 71. The cleaning frame 71 is made of a material having a density of about 0.95 to 1.10 g / cm 3 The cleaning frame 71 supports the charging roller 66 as a rotating member for rotation via the charging roller bearing 67. The charging roller 66 rotates while receiving a predetermined bias voltage to uniformly charge the surface of the photosensitive drum 62. In order to apply a predetermined bias voltage to the charging roller 66, the cleaning unit 60 includes an electrode plate 82 as a conductive path from the imaging device A to the charging roller 66, which is an electrode member made of metal. The electrode plate 82 has a contact surface 82a exposed to the outside to receive power from the spring contact 1752 (which is a power supply member provided in the imaging device).

[0122] The cleaning unit 60 further includes a contact cover 83 which serves as a second frame and is made of a material having a density of about 1.12 to 1.50 g / cm 3 And it is made of a material with a flame retardancy of V-1 according to the UL94 standard, that is, it has a higher flame retardancy than the cleaning frame 71. Fig. 12BAs shown, a part of the contact cover 83 as a contact protection member has a protruding portion 83a protruding beyond the contact surface 82a in the longitudinal direction W. For example, when a bias is applied in a state where a combustible foreign matter (such as dust) is sandwiched between the spring contact 1752 and the contact surface 82a of the electrode plate 82, the foreign matter may be ignited due to tracking. In this case, the protruding portion 83a made of a highly flame-retardant material serves as a fire spread prevention wall that prevents fire from spreading to the inside of the box B including the cleaning frame 71.

[0123] That is, in the box B of the present embodiment, the cleaning frame 71 is made of HB material (i.e., low-density resin material) to reduce the overall weight of the product. On the other hand, the protruding portion 83a made of highly flame-retardant V-1 material is arranged between the cleaning frame 71 and the connecting portion, which is a conductive path between the device body A and the box B. This provides a box B that achieves both safety and weight reduction of the entire product.

[0124] In this embodiment, the cleaning frame 71 as the first frame is made of PS, the contact cover 83 as the second frame is made of PC-ABS, and the electrode plate 82 as the metal electrode member is made of stainless steel. However, these materials are not limited to those of this embodiment.

[0125] In the present embodiment, the process box B is formed by integrating the developing unit 20 and the cleaning unit 60. However, the construction of the box according to the present invention is not limited to the construction of the present embodiment. For example, in a device construction in which the developing unit 20 and the cleaning unit 60 can be independently attached to and detached from the device main body, each unit can be equivalent to the box according to the present invention. This also applies to the embodiment described below.

[0126] Another embodiment of the above-mentioned charging contact configuration will now be described.

[0127] Reference Fig.34A , 34B , 35, 36A and 36B, another embodiment of the charging contact structure is now described in detail. Fig.34A : is a perspective view showing a cleaning frame main body portion extracted independently as a key component of the charging contact configuration. Fig.34B : is a perspective view showing key parts of the charging contact configuration extracted in a state where the contact cover portion is formed in the cleaning frame main body portion by two-color molding. Fig.35 is an exploded perspective view showing key components of the charging contact configuration extracted. Fig.36A It is a side view for showing the configuration of the charging contact. Fig.36B is along Fig.36A The enlarged cross-sectional view of the charging contact taken along the line HH in FIG. Fig.10A modification is described in which the contact cover 83 as the second frame is formed integrally with the cleaning frame 3071. The other configurations are the same and therefore not described.

[0128] like Fig.35 As shown, the cleaning unit 3060 includes a cleaning frame 3071 as a first frame.

[0129] like Fig.34A and 34B As shown, the cleaning frame 3071 includes a cleaning frame main body 3071a and a cleaning frame contact cover 3071b. The cleaning frame contact cover 3071b is formed integrally with the cleaning frame main body 3071a by two-color molding. The cleaning frame main body 3071a is made of a material having a density of about 0.95 to 1.10 g / cm 3 The cleaning frame contact cover portion 3071b is made of a material having a flame retardant performance of HB according to the UL94 standard. The density is about 1.12 to 1.50 g / cm 3 And it is made of a material with a flame retardancy of V-1 according to the UL94 standard, that is, it has higher flame retardancy than the cleaning frame 3071.

[0130] like Fig.36B As shown, a portion of the cleaning frame contact cover portion 3071b as a contact protection member has a protruding portion 3071c that protrudes beyond the contact surface 3082a in the longitudinal direction WW.

[0131] For example, when bias is applied in a state where flammable foreign matter (e.g., dust) is sandwiched between the spring contact 3752 and the contact surface 3082a of the electrode plate 3082, the foreign matter may be ignited due to tracking. In this case, the protruding portion 3071c made of a highly flame-retardant material serves as a fire spread prevention wall that prevents fire from spreading to the inside of the box including the cleaning frame 3071.

[0132] That is, in the box of the present embodiment, the cleaning frame 3071 is also made of HB material (which is a low-density resin material), thereby reducing the overall weight of the product, as described above. On the other hand, the protruding portion 3071c made of highly flame-retardant V-1 material is arranged between the cleaning frame 3071 and the connecting portion, which is a conductive path between the device body and the box. This provides a box that simultaneously achieves safety and weight reduction of the entire product.

[0133] In this embodiment, the cleaning frame main body 3071a of the cleaning frame 3071 as the first frame uses PS, the cleaning frame contact cover part 3071b having a function similar to that of the above-mentioned second frame uses PC-ABS, and the electrode plate 3082 as the metal electrode part uses stainless steel. However, these materials are not limited to the materials of this embodiment.

[0134] Second embodiment

[0135] Overall structure of imaging device 2600

[0136] refer to Fig.16 Now, the overall structure of an electrophotographic image forming apparatus 2600 (hereinafter referred to as image forming apparatus 2600) according to a second embodiment of the present invention will be described. Fig.16 2 is a schematic diagram of an image forming apparatus 2600 according to the present embodiment. In the present embodiment, the process cartridge 2500 and the toner cartridge 2550 are attachable to and detachable from the apparatus main body of the image forming apparatus 2600. In the present embodiment, the first to fourth image forming parts have substantially the same construction and operation except that they form images of different colors. Therefore, in the case where it is not necessary to distinguish these parts, these parts will be collectively described without using suffixes Y to K.

[0137] The first to fourth process boxes 2500 are arranged side by side in the horizontal direction. Each process box 2500 includes a cleaning unit 2501 and a developing unit 2502. The cleaning unit 2501 includes a photosensitive drum 2503 as an image bearing member, a charging roller 2504 as a charging unit for uniformly charging the surface of the photosensitive drum 2503, and a cleaning blade 2505 as a cleaning unit. The developing unit 2502 accommodates a developing roller 2506 and a developer T (hereinafter referred to as a toner), and includes a developing device for developing the electrostatic latent image on the photosensitive drum 2503. The cleaning unit 2501 and the developing unit 2502 are supported in a pivotable manner relative to each other. The first process box 2500Y accommodates yellow (Y) toner in the developing unit 2502. Similarly, the second process cartridge 2500M accommodates magenta (M) toner, the third process cartridge 2500C accommodates cyan (C) toner, and the fourth process cartridge 2500K accommodates black (K) toner.

[0138] The process cartridge 2500 can be attached to and detached from the image forming apparatus 2600 via an attachment unit (not shown) such as an attachment guide and a positioning member (not shown) provided in the image forming apparatus 2600. A scanner unit 2601 as an exposure unit for forming an electrostatic latent image is arranged below the process cartridge 2500. In addition, the image forming apparatus further includes a waste toner conveying unit 2616 arranged at the rear of the process cartridge 2500 (at the downstream side in the attachment / detachment direction of the process cartridge 2500).

[0139] The first to fourth toner cartridges 2550 are arranged side by side in the horizontal direction below the process cartridge 2500 in an order corresponding to the colors of the toners contained in the process cartridge 2500. That is, the first toner cartridge 2550Y contains yellow (Y) toner. Similarly, the second toner cartridge 2550M contains magenta (M) toner, the third toner cartridge 2550C contains cyan (C) toner, and the fourth toner cartridge 2550K contains black (K) toner. Each toner cartridge 2550 supplies toner to the process cartridge 2500 containing the same color toner.

[0140] When a toner level detection unit (not shown) installed in the apparatus body of the image forming apparatus 2600 detects that the toner remaining in the process cartridge 2500 is insufficient, a replenishment operation of the toner cartridge 2550 is performed. The toner cartridge 2550 can be attached to and detached from the image forming apparatus 2600 by an attachment unit (not shown) such as an attachment guide and a positioning member (not shown) provided in the image forming apparatus 2600. The process cartridge 2500 will be described in detail below.

[0141] The first to fourth toner conveying devices 2602 are arranged below the toner box 2550 corresponding to each toner box 2550. Each toner conveying device 2602 conveys the toner received from the toner box 2550 upward to supply the toner to the corresponding developing unit 2502. The intermediate transfer unit 2604 as an intermediate transfer component is arranged above the processing box 2500. The intermediate transfer unit 2604 is arranged substantially horizontally, and its primary transfer portion S1 is located at the lower side. The intermediate transfer belt 2603 as a rotating endless belt faces the photosensitive drum 2503 and is stretched on a plurality of tension rollers. On the inner surface of the intermediate transfer belt 2603, the primary transfer rollers 2605 as the primary transfer component are located at various positions where they form the primary transfer portion S1 with each photosensitive drum 2503 across the intermediate transfer belt 2603. A secondary transfer roller 2606 as a secondary transfer member is in contact with the intermediate transfer belt 2603, and forms a secondary transfer portion S2 with a roller located on the opposite side across the intermediate transfer belt 2603. In addition, an intermediate transfer belt cleaning unit 2607 is arranged on the side opposite to the secondary transfer portion S2 in the left-right direction (the direction in which the secondary transfer portion S2 and the intermediate transfer belt are stretched).

[0142] The fixing unit 2608 is further located above the intermediate transfer unit 2604. The fixing unit 2608 includes a heating unit 2609 and a pressing roller 2610 pressed on the heating unit 2609. An ejection tray 2611 is arranged on the upper surface of the apparatus body, and a waste toner collection container 2612 is arranged between the ejection tray 2611 and the intermediate transfer unit. In addition, a paper feed tray 2613 is located at the bottom of the apparatus body for storing recording material 2700.

[0143] Imaging process

[0144] Reference Fig.16 and 17 , the imaging operation of the imaging device 2600 is now described. Fig.17 is a schematic sectional view of the process cartridge according to the present embodiment.

[0145] During image formation, the photosensitive drum 2503 is driven to Fig.17 The intermediate transfer belt 2603 is driven to rotate along the direction of the arrow a at a predetermined speed. Fig.16 Rotates in the direction of arrow b (along the forward rotation direction of the photosensitive drum 2503).

[0146] First, the charging roller 2504 uniformly charges the surface of the photosensitive drum 2503. Then, a laser beam is emitted from the scanner unit 2601 to the surface of the photosensitive drum 2503 for scanning exposure, thereby forming an electrostatic latent image on the photosensitive drum 2503 according to the image information. The electrostatic latent image formed on the photosensitive drum 2503 is developed into a toner image (developer image) by the developing unit 2502. At this time, the developing unit 2502 is pressurized by a developing pressure unit (not shown) provided in the main body of the imaging device 2600. The toner image formed on the photosensitive drum 2503 is transferred (as a primary transfer) to the intermediate transfer belt 2603 by the primary transfer roller 2605.

[0147] For example, to form a full-color image, the above-described processes are sequentially performed in the image forming portions S1Y to S1K as the first to fourth primary transfer units so that toner images of different colors are sequentially superimposed on the intermediate transfer belt 2603 .

[0148] At the same time, the recording material 2700 stored in the paper feed tray 2613 is fed at a predetermined control timing and conveyed to the secondary transfer portion S2 in synchronization with the movement of the intermediate transfer belt 2603. Then, the four-color toner image on the intermediate transfer belt 2603 is collectively transferred (as secondary transfer) onto the recording material 2700 by the secondary transfer roller 2606 that contacts the intermediate transfer belt 2603 with the recording material 2700 interposed therebetween.

[0149] Then, the recording material 2700 to which the toner image is transferred is conveyed to the fixing unit 2608. The fixing unit 2608 heats and pressurizes the recording material 2700, thereby fixing the toner image on the recording material 2700. After fixing, the recording material 2700 is conveyed to the discharge tray 2611 to complete the imaging operation. In addition, the cleaning blade 2505 removes the primary transfer residual toner (waste toner) remaining on the photosensitive drum 2503 after the primary transfer step. The intermediate transfer belt cleaning unit 2607 removes the secondary transfer residual toner (waste toner) remaining on the intermediate transfer belt 2603 after the secondary transfer step. The waste toner removed by the cleaning blade 2505 and the intermediate transfer belt cleaning unit 2607 is conveyed by the waste toner conveying unit 2616 provided in the main body of the device and stored in the waste toner collecting container 2612. The imaging device 2600 can also form a monochrome or multi-color image by using only one or some (but not all) desired imaging portions.

[0150] Processing box

[0151] Reference Fig.17 18, the overall configuration of the process cartridge 2500 to be attached to the image forming apparatus 2600 according to the present embodiment will now be described. Fig.17 is a schematic cross-sectional view of the process cartridge 2500 according to the present embodiment. Fig.18A 25. It is a perspective view of the process cartridge 2500 as viewed from the bottom surface side. Fig.18B 25 is a perspective view of the process cartridge 2500 as viewed from the top surface side.

[0152] The process cartridge 2500 includes a cleaning unit 2501 and a developing unit 2502. The cleaning unit 2501 and the developing unit 2502 are connected in a pivotable manner around a rotation support pin 2507.

[0153] The cleaning unit 2501 includes a cleaning frame 2508 that supports various components in the cleaning unit 2501. In addition to the photosensitive drum 2503, the charging roller 2504, and the cleaning blade 2505, the cleaning unit 2501 also includes a waste toner screw 2509 extending parallel to the rotation axis of the photosensitive drum 2503. The cleaning frame 2508 includes cleaning bearings 2511 that rotatably support the photosensitive drum 2503 at opposite longitudinal ends of the cleaning unit 2501. The cleaning bearing 2511 includes a cleaning gear train for transmitting drive from the photosensitive drum 2503 to the waste toner screw 2509.

[0154] The charging roller 2504 is urged toward the photosensitive drum 2503 in the direction of arrow c by charging roller pressure springs 2512 arranged at both ends. The charging roller 2504 is configured to be driven by the photosensitive drum 2503. When the photosensitive drum 2503 is driven to rotate in the direction of arrow a during image formation, the charging roller 2504 rotates in the direction of arrow d (the forward rotation direction of the photosensitive drum 2503).

[0155] The cleaning blade 2505 includes an elastic member 2505a for removing transfer residual toner (waste toner) remaining on the surface of the photosensitive drum 2503 after the primary transfer, and a supporting member 2505b for supporting the elastic member 2505a. The waste toner removed from the surface of the photosensitive drum 2503 by the cleaning blade 2505 is stored in a waste toner storage chamber 2513 defined by the cleaning blade 2505 and the cleaning frame 2508. The waste toner screw 2509 in the waste toner storage chamber 2513 conveys the waste toner stored in the waste toner storage chamber 2513 to the rear of the image forming apparatus 2600 (the downstream side in the attachment / detachment direction of the process cartridge 2500). The conveyed waste toner is discharged through the waste toner discharge portion 2618 and is sent to the waste toner conveying unit 2616 of the image forming apparatus 2600.

[0156] The developing unit 2502 has a developing frame 2614 that supports various components of the developing unit 2502. The developing frame 2614 is divided into a developing chamber 2514a that accommodates the developing roller 2506 and the supply roller 2515, and a toner storage chamber 2514b that stores toner and accommodates the stirring member 2516.

[0157] The developing chamber 2514a accommodates a developing roller 2506, a supply roller 2515, and a developing blade 2517. The developing roller 2506 carries toner as a developer carrying member, rotates in the direction of arrow e during image formation, and conveys toner to the photosensitive drum 2503 by contacting the photosensitive drum 2503. The developing roller 2506 is rotatably supported by the developing frame 2514 via developing bearing units 2518 at opposite ends in its longitudinal direction (rotation axis direction). The supply roller 2515 as a developer supply member is rotatably supported by the developing frame 2514 via the developing bearing unit 2518 so as to be rotatably contacted with the developing roller 2506. The supply roller 2515 rotates in the direction of arrow f during image formation. In addition, the developing blade 2517 as a layer thickness control member that controls the thickness of the toner layer formed on the developing roller 2506 is arranged to contact the surface of the developing roller 2506.

[0158] The toner storage chamber 2514b accommodates a stirring member 2516, which stirs the stored toner T and conveys the toner to the supply roller 2515 through the developing chamber communication port 2514c. The stirring member 2516 includes a rotating shaft 2516a parallel to the rotation axis of the developing roller 2506, and a flexible stirring blade 2516b as a conveying member. One edge of the stirring blade 2516b is fixed to the rotating shaft 2516a, and the other edge of the stirring blade 2516b is a free edge. When the rotating shaft 2516a rotates, the stirring blade 2516b rotates in the direction of the arrow g, thereby stirring the toner through the stirring blade 2516b.

[0159] The developing unit 2502 has a developing chamber communication port 2514c provided between the developing chamber 2514a and the toner storage chamber 2514b. In the present embodiment, when the developing unit 2502 is in a normal orientation (orientation during use), the developing chamber 2514a is located above the toner storage chamber 2514b. The toner in the toner storage chamber 2514b lifted by the stirring member 2516 is supplied to the developing chamber 2514a through the developing chamber communication port 2514c.

[0160] The developing unit 2502 also has a receiving port 2519 at one end on the downstream side in the attachment / detachment direction. A receiving port sealing component 2520 and a toner receiving port baffle 2521 that can move in the front-rear direction are arranged above the toner receiving port 2519. When the processing box 2500 is not attached to the imaging device 2600, the toner receiving port baffle 2521 closes the toner receiving port 2519. The toner receiving port baffle 2521 is configured to be pushed and opened by the imaging device 2600 in conjunction with the attachment / detachment operation of the processing box 2500. The receiving and conveying channel 2522 is arranged in communication with the toner receiving port 2519, and the receiving and conveying screw 2523 is arranged in the receiving and conveying channel 2522. A storage chamber communication port 2524 for supplying toner to the toner storage chamber 2514b is provided near the longitudinal center of the developing unit 2518, and provides communication between the receiving and conveying passage 2522 and the toner storage chamber 2514b. The receiving and conveying screw 2523 extends parallel to the rotational axis of the developing roller 2506 and the supply roller 2515, and conveys the toner received from the toner receiving port 2519 to the toner storage chamber 2514b through the storage chamber communication port 2524.

[0161] Development contact structure

[0162] Reference Fig.15 , 19 , 20A and 20B, the developing contact structure which is a feature of this embodiment will now be described in detail. Fig.15is an exploded perspective view of the developer unit 2502, showing the key components of the developer contact structure extracted. Fig.19 is a perspective view of the developing unit 2502, Fig. 20A is a side view for illustrating the structure of the developing contact, Fig. 20B is along Fig. 20A An enlarged cross-sectional view of the developing contact taken along line BB in FIG.

[0163] like Fig.15 As shown, the developing unit 2502 includes a developing frame 2514 as a first frame and a developing roller 2506 as a process unit. The developing frame 2514 is made of a material having a density of about 0.95 to 1.10 g / cm 3 And it is made of a material with a flame retardant property of HB according to the UL94 standard. It is well known that adding additives to resin materials (which usually have the property of being ignited when in contact with fire) can make the resin have flame retardant properties. When additives are added to a type of resin material, a higher flame retardant effect will result in a larger specific gravity of the resin. This may cause the weight of the necessary resin material in the entire product to increase, thereby causing a greater burden on the environment. In this embodiment, the developing frame 2514 is made of a material that does not contain such additives and has a low density. The developing roller 2506 has the function of carrying the developer by receiving a predetermined bias voltage. The developing roller 2506, which is a rotating component, is rotatably supported by the developing frame 2514 via the developing bearing unit 2518.

[0164] like Fig.15 , 20A 20B, the developing bearing unit 2518 includes a conductive portion 2530 as an electrode member made of conductive resin to apply a predetermined bias to the developing roller 2506. The conductive portion 2530 forms a conductive path from the developing spring contact 2620 (which is a power supply member of the image forming apparatus) to the developing roller 2506.

[0165] like Fig.15 As shown, the developing bearing unit 2518 is formed by integrally forming a conductive portion 2530 and a non-conductive portion 2531 as a second frame by two-color molding or the like. The non-conductive portion 2531 is made of a material having a density of about 1.12 to 1.50 g / cm 3 And it is made of a material with a flame retardancy of V-0 according to the UL94 standard, that is, it has a higher flame retardancy than the developing frame 2514. Fig.15 As shown, the conductive portion 2530 includes a conductive portion exposed to the outside to contact with the developer spring contact 2620 (which is a power supply component of the imaging device) ( Fig. 20B ) contact portion 2530a for receiving power, and a conductive support portion 2530b for rotatably supporting the developing roller 2506.

[0166] like Fig. 20B As shown, in this configuration, the non-conductive portion 2531 as the second frame forms a seating surface for forming the conductive portion 2530. When the seating surface formed by the non-conductive portion 2531 is 2531a, the non-conductive portion 2531 has a protruding portion 2531b adjacent to the conductive portion 2530 and protruding beyond the seating surface 2531a in a direction perpendicular to the seating surface 2531a. The conductive portion 2530 is formed by two-color molding in such a manner that it is surrounded by the non-conductive portion 2531 except for the surface to be in contact with the developing spring contact 2620.

[0167] For example, an abnormality in the high voltage power supply may cause discharge at the contact surface 2530a between the developing spring contact 2620 (which is the power supply portion) and the conductive portion 2530 of the imaging device body. This may generate an electrical ignition source. In this regard, the present construction has a non-conductive portion 2531 that is highly flame-retardant and surrounds the conductive portion 2530. With this construction, if any ignition at the contact surface 2530a is about to spread the fire to the non-conductive portion 2531, the non-flammable gas generated from the inside of the material of the non-conductive portion 2531 acts to extinguish the flame, thereby preventing the fire from spreading to the developing frame 2514.

[0168] That is, in this embodiment, the developing frame 2514 is also made of HB material (which is a low-density resin material) to reduce the overall weight of the product, and a highly flame-retardant V-0 material is used near the connecting portion between the device body and the process cartridge as a conductive path. This provides a process cartridge that achieves safety and weight reduction of the entire product weight at the same time.

[0169] Charging contact structure

[0170] Reference Fig.17 , 21 , 22A and 22B, the charging contact structure which is a feature of this embodiment will now be described in detail. Fig.21 is an exploded perspective view showing key components of the charging contact configuration extracted. Fig.22A It is a side view for showing the configuration of the charging contact. Fig. 22B is along Fig.22A An enlarged cross-sectional view of the charging contact taken along line EE in FIG.

[0171] like Fig.17 As shown, the cleaning unit 2501 includes a cleaning frame 2508 as a first frame and a charging roller 2504 as a process unit (charging member). The cleaning frame 2508 is made of a material having a density of about 0.95 to 1.10 g / cm 3The cleaning frame 2508 supports the charging roller 2504 as a rotating member for rotation via the charging roller bearing 2525. The charging roller bearing 2525 includes a charging roller bearing member 2526 made of a conductive resin and a charging roller spring member 2512 formed of a metal compression spring. The charging roller 2504 rotates while receiving a predetermined bias voltage so that the surface of the photosensitive drum 2503 is uniformly charged. In order to apply a predetermined bias voltage to the charging roller 2504, the cleaning unit 2501 includes Fig.21 The electrode plate 2528 shown in FIG. 25 is an electrode member made of metal as a conductive path from the image forming device 2600 to the charging roller 2504. Fig. 22B As shown, the electrode plate 2528 has a contact surface 2528a exposed outwardly to receive power from a spring contact 2619 (which is a power supply component provided in the imaging device).

[0172] The cleaning unit 2501 further includes a contact cover 2529 as a second frame. The contact cover 2529 is made of a material having a density of about 1.12 to 1.50 g / cm 3 And it is made of materials with flame retardancy of V-0 according to UL94 standard, which means it has higher flame retardancy than cleaning frame 2508. Fig. 22B As shown, a part of the contact cover 2529 has a protruding portion 2529a that protrudes beyond the contact surface 2528a in the longitudinal direction W. For example, when a combustible foreign matter (such as dust) is left between the spring contact 2619 and the contact surface 2528a of the electrode plate 2528, the foreign matter may cause a fire due to tracking. In this case, the protruding portion 2529a made of a highly flame-retardant material serves as a fire spread prevention wall. This prevents the fire from spreading to the inside of the processing box 2500 including the cleaning frame 2508.

[0173] That is, the cleaning frame 2508 is made of HB material, which is a low-density resin material, to reduce the overall weight of the product, while the protruding portion 2529a made of a highly flame-retardant V-0 material is located at the conductive path between the device body 2600 and the cleaning frame 2508. This provides a box that achieves both safety and weight reduction of the entire product.

[0174] Third embodiment

[0175] A third embodiment according to the present invention will now be described with reference to the accompanying drawings. The third embodiment is an example of an imaging device to which four process cartridges can be attached and detached. The number of process cartridges attached to the imaging device is not limited thereto but can be appropriately set. In addition, in the following embodiments, a laser beam printer is described as an example of an imaging device.

[0176] Overview of the imaging device configuration

[0177] Fig.23 is a schematic cross-sectional view of an imaging device M, Fig.24 28 is a cross-sectional view of a process cartridge 2800. The image forming apparatus M is a four-color full-color laser printer using an electrophotographic process and forms a color image on a recording medium (recording material) S, and the image forming apparatus M uses a process cartridge system. The process cartridge 2800 is detachably attached to the image forming apparatus main body 2870 and is used to form a color image on the recording medium S.

[0178] The side of the imaging device M including the front door 2711 is referred to as the front surface, and the side opposite to the front surface is referred to as the back (rear) surface. The right side of the imaging device M when viewed from the front is referred to as the drive side, and the left side is referred to as the non-drive side. The upper side of the imaging device M when viewed from the front is referred to as the upper surface, and the lower side is referred to as the lower surface. Fig.23 It is a cross-sectional view of the imaging device M observed from the non-driving side. The front side in the direction perpendicular to the drawing plane is the non-driving side of the imaging device M, the right side in the figure is the front of the imaging device M, and the rear side in the direction perpendicular to the drawing plane is the driving side of the imaging device M.

[0179] Likewise, when viewed in the axial direction of the photosensitive drum, the drive side of the process cartridge 2800 is the side on which the drum coupling member (photosensitive coupling member) to be described below is arranged. In addition, when viewed in the axial direction of the developing roller (developing member), the drive side of the process cartridge 2800 is the side on which the developing coupling member to be described below is arranged.

[0180] The first to fourth process boxes 2800 (2800Y, 2800M, 2800C and 2800K) are arranged in the imaging device main body 2870 along a substantially horizontal direction. The first to fourth process boxes 2800 (2800Y, 2800M, 2800C and 2800K) have the same electrophotographic processing mechanism, but the color of the developer (hereinafter referred to as toner) is different. The first to fourth process boxes 2800 (2800Y, 2800M, 2800C and 2800K) receive the rotational driving force transmitted from the drive output part (details will be described below) of the imaging device main body 2870. In addition, the imaging device main body 2870 provides a bias voltage (charging bias, developing bias, etc.) (not shown) to each of the first to fourth process boxes 2800 (2800Y, 2800M, 2800C and 2800K).

[0181] like Fig.24As shown, each of the first to fourth process cartridges 2800 of the present embodiment includes a photosensitive drum 2804 and a drum unit 2808, and the drum unit has a charging unit as a process unit acting on the photosensitive drum 2804. In some examples, the drum unit 2808 may include a cleaning unit and a charging unit as a process unit. In addition, each of the first to fourth process cartridges 2800 (2800Y, 2800M, 2800C, and 2800K) includes a developing unit 2809, which has a developing unit for developing the electrostatic latent image on the photosensitive drum 2804.

[0182] The drum unit 2808 and the developing unit 2809 are connected to each other. A detailed description of the process cartridge 2800 will be given below. The first process cartridge 2800Y accommodates yellow (Y) toner in the developing frame 2825, and forms a yellow toner image on the surface of the photosensitive drum 2804. The second process cartridge 2800M accommodates magenta (M) toner in the developing frame 2825, and forms a magenta toner image on the surface of the photosensitive drum 2804. The third process cartridge 2800C accommodates cyan (C) toner in the developing frame 2825, and forms a cyan toner image on the surface of the photosensitive drum 2804. The fourth process cartridge 2800K accommodates black (K) toner in the developing frame 2825, and forms a black toner image on the surface of the photosensitive drum 2804.

[0183] A laser scanner unit 2714 as an exposure unit is provided above the first to fourth process cartridges 2800 (2800Y, 2800M, 2800C, and 2800K). The laser scanner unit 2714 outputs a laser beam L according to image information. The laser beam L passes through an exposure window 2810 of the process cartridge 2800 and performs scanning exposure on the surface of the photosensitive drum 2804. An intermediate transfer unit 2712 as a transfer member is provided below the first to fourth process cartridges 2800 (2800Y, 2800M, 2800C, and 2800K). The intermediate transfer unit 2712 includes a driving roller 2712e, a rotating roller 2712c, and a tension roller 2712b, and a flexible transfer belt 2712a arranged around these rollers. The lower surface of each of the photosensitive drum 2804 of the first to fourth process boxes 2800 (2800Y, 2800M, 2800C and 2800K) contacts the upper surface of the transfer belt 2712a. The contact portion serves as a primary transfer portion. On the inner side of the transfer belt 2712a, the primary transfer roller 2712d is aligned with the photosensitive drum 2804.

[0184] The secondary transfer roller 2706 contacts the driving roller 2712e via the transfer belt 2712a. The contact portion between the transfer belt 2712a and the secondary transfer roller 2706 serves as a secondary transfer portion. A feed unit 2704 is provided below the intermediate transfer unit 2712. The feed unit 2704 includes a paper feed tray 2704a for accommodating a recording medium S, and a paper feed roller 2704b.

[0185] like Fig.23 When viewed from the top, a fixing device 2707 and a paper discharge device 2708 are provided in the upper left portion of the imaging device body 2870. The upper surface of the imaging device body 2870 serves as a paper discharge tray 2713. The fixing device of the fixing device 2707 fixes the toner image on the recording medium S, and then the recording medium is discharged onto the paper discharge tray 2713.

[0186] Imaging Operation

[0187] The operation for forming a full-color image is as follows. The photosensitive drum 2804 of each of the first to fourth process cartridges 2800 (2800Y, 2800M, 2800C, and 2800K) is driven at a predetermined speed (along the direction of rotation). Fig.24 The device rotates in the direction of arrow A.

[0188] The transfer belt 2712a is also driven in the normal rotation direction (direction) of the photosensitive drum 2804 at a speed corresponding to the speed of the photosensitive drum 2804. Fig.23 The laser scanner unit 2714 is also driven. In synchronization with the driving of the laser scanner unit 2714, each charging roller 2805 in each processing box uniformly charges the surface of the photosensitive drum 2804 to a predetermined polarity and potential. The laser scanner unit 2714 scans and exposes the surface of each photosensitive drum 2804 with a laser beam L according to an image signal of each color. As a result, an electrostatic latent image corresponding to the image signal of the corresponding color is formed on the surface of each photosensitive drum 2804. The formed electrostatic latent image is developed by the developing roller 2806 driven to rotate at a predetermined speed.

[0189] By the above-mentioned electrophotographic imaging processing operation, a yellow toner image corresponding to the yellow component in the full-color image is formed on the photosensitive drum 2804 of the first process box 2800Y. Then, this toner image is transferred (as a primary transfer) to the transfer belt 2712a. Similarly, a magenta toner image corresponding to the magenta component in the full-color image is formed on the photosensitive drum 2804 of the second process box 2800M. Then, this toner image is superimposed on the yellow toner image that has been transferred to the transfer belt 2712a as a primary transfer. Similarly, a cyan toner image corresponding to the cyan component in the full-color image is formed on the photosensitive drum 2804 of the third process box 2800C. Then, this toner image is superimposed on the yellow and magenta toner images that have been transferred to the transfer belt 2712a as a primary transfer. Similarly, a black toner image corresponding to the black component in the full-color image is formed on the photosensitive drum 2804 of the fourth process cartridge 2800K. This toner image is then superimposed as a primary transfer on the yellow, magenta and cyan toner images transferred onto the transfer belt 2712a.

[0190] In this way, unfixed full-color toner images of four colors, yellow, magenta, cyan and black, are formed on the transfer belt 2712a. At the same time, the recording medium S is fed individually one by one at a predetermined control timing. The recording medium S is introduced into the secondary transfer portion, which is the contact portion between the secondary transfer roller 2706 and the transfer belt 2712a, at a predetermined control timing. Therefore, when the recording medium S is conveyed through the secondary transfer portion, the four-color toner images superimposed on the transfer belt 2712a are collectively transferred to the surface of the recording medium S in sequence. Further details of the construction of the imaging device body will be described below.

[0191] Overview of Process Cartridge Attachment / Detachment Structure

[0192] Reference Figures 25 to 27 , a box tray (hereinafter referred to as a tray) 2871 supporting the processing box 2800 will now be described in detail. Fig.25 28 is a cross-sectional view of the imaging device M in a state where the front door 2711 is opened and the tray 2871 is located in the imaging device body 2870. Fig.26 27 is a cross-sectional view of the image forming apparatus M in a state where the front door 2711 is opened, the tray 2871 is located outside the image forming apparatus main body 2870, and the process cartridge 2800 is accommodated in the tray. Fig. 27 27 is a cross-sectional view of the image forming apparatus M in a state where the front door 2711 is opened, the tray 2871 is located outside the image forming apparatus main body 2870 , and the process cartridge 2800 is removed from the tray 2871 .

[0193] like Fig.25 and 26As shown, the tray 2871 can move relative to the imaging device body 2870 in the substantially horizontal arrow X1 direction (push-in direction) and the substantially horizontal arrow X2 direction (pull-out direction). That is, the tray 2871 is arranged so that it can be pulled out of the imaging device body 2870 and pushed into the imaging device body 2870. When the imaging device body 2870 is installed on a horizontal surface, the tray 2871 can be moved substantially in the horizontal direction. The state where the tray 2871 is located outside the imaging device body 2870 ( Fig.26 The state shown in FIG. 27 is referred to as the external position. The state in which the front door 2711 is opened, the tray 2871 is located inside the imaging device body 2870, and the photosensitive drum 2804 is separated from the transfer belt 2712a ( Fig.25 The state in ) is called the internal position.

[0194] like Fig. 27 As shown, tray 2871 includes attachment portion 2871a, to which process box 2800 is detachably attached at an external position. Along with the movement of tray 2871, process box 2800 placed at attachment portion 2871a moves into imaging device main body 2870. In this movement, a gap is maintained between transfer belt 2712a and each photosensitive drum 2804. In the present embodiment, closing front door 2711 causes connecting rod mechanism (not shown) to lift intermediate transfer unit 2712 to a position for imaging (position where intermediate transfer belt 2712a contacts photosensitive drum 2804) along the direction of arrow Z1. Opening front door 2711 lowers intermediate transfer unit 2712 along the direction of arrow Z2, thereby separating intermediate transfer belt 2712a from photosensitive drum 2804. Therefore, the tray 2871 can move the process cartridge 2800 into the imaging device body 2870 without bringing the photosensitive drum 2804 into contact with the transfer belt 2712a. As described above, the tray 2871 allows a plurality of process cartridges 2800 to be moved together to a position in the imaging device body 2870 where imaging can be performed, and also allows the plurality of process cartridges 2800 to be pulled out of the imaging device body 2870 together.

[0195] Overall structure of the processing box

[0196] Reference Fig.24 , 28 , 29, 30 and 31, the structure of the processing box 2800 is now described. Fig.28 is an exploded perspective view of the drum unit 2808. Fig.29 is an exploded perspective view of the developing unit 2809. Fig.30 14 is an exploded perspective view of the process cartridge 2800 as viewed from the driving side (which is one end side in the axial direction of the photosensitive drum 2804). Fig.31 This is an assembly perspective view of the process cartridge 2800 as viewed from the driving side.

[0197] In the present embodiment, the first to fourth process cartridges 2800 (2800Y, 2800M, 2800C, and 2800K) have the same electrophotographic process mechanism but contain toners of different colors and amounts.

[0198] Each processing box 2800 includes a photosensitive drum 2804 (2804Y, 2804M, 2804C, 2804K) and a processing unit acting on the photosensitive drum 2804. The processing unit includes a charging roller 2805 as a charging unit for charging the photosensitive drum 2804, a developing roller 2806 as a developing unit for developing a latent image formed on the photosensitive drum 2804, and the like. The processing box 2800 is divided into a drum unit 2808 (2808Y, 2808M, 2808C, 2808K) and a developing unit 2809 (2809Y, 2809M, 2809C, 2809K). In the following description, the longitudinal directions (Y1 and Y2 directions) of the drum unit 2808 and the developing unit 2809 are directions substantially parallel to the rotation axis ax of the photosensitive drum 2810.

[0199] Drum unit structure

[0200] like Fig.28 and 30 As shown, drum unit 2808 comprises photosensitive drum 2804, charging roller 2805 and drum frame 2815 as first frame.Charging roller 2805 is rotationally supported by driving side charging roller bearing 2820a and non-driving side charging roller bearing 2820b, and is pushed toward photosensitive drum 2804 by pressing springs 2821a and 2821b.Photosensitive drum 2804 is rotationally supported by driving side box cover component 2816 at opposite ends in the longitudinal direction of process cartridge 2800 and non-driving side box cover component 2817 as second frame.Non-driving side box cover component 2817 comprises electrode component 2860 that receives power from imaging device main body 2870.Details will be described below.

[0201] like Fig.30 and 31 As shown, a coupling member 2843 for transmitting a driving force to the photosensitive drum 2804 is provided at one longitudinal end of the photosensitive drum 2804. The coupling member 2843 is connected to the main drum drive coupling member 2880 (see Fig.26 ) is engaged, and the main drum drive coupling member serves as a drum drive output portion of the imaging device main body 2870. The driving force of the driving motor (not shown) of the imaging device main body 2870 is transmitted to the photosensitive drum 2804 through the coupling member 2843, and the photosensitive drum 2804 moves along the arrow A ( Fig.24) direction. In addition, the photosensitive drum 2804 includes a drum flange 2842 at the other longitudinal end. The charging roller 2805 is supported by the drum frame 2815 so as to contact with the photosensitive drum 2804 and rotate through the photosensitive drum 2804.

[0202] Development unit structure

[0203] like Fig.24 and 29 As shown, the developing unit 2809 includes a developing roller 2806, a toner conveying roller 2807, a developing blade 2830, a developing frame 2825, etc. The developing frame 2825 as the fourth frame (fourth component) includes a lower frame 2825a and a cover component 2825b. The lower frame 2825a and the cover component 2825b have a flame retardant performance of HB according to the UL94 standard. The lower frame 2825a is bonded to the cover component 2825b by ultrasonic welding, etc. The developing frame 2825 includes a toner storage portion 2829 for storing the toner to be supplied to the developing roller 2806. The developing frame 2825 rotatably supports the developing roller 2806 and the toner conveying roller 2807 by a driving side bearing 2826 and a non-driving side bearing 2827, and maintains a developing blade 2830 that controls the layer thickness of the toner on the periphery of the developing roller 2806.

[0204] The developing blade 2830 is formed by bonding an elastic member 2830b (which is a metal sheet having a thickness of about 0.1 mm) to a supporting member 2830a (which is a metal material having an L-shaped cross section) by welding, etc. The developing blade 2830 is fixed to the developing frame 2825 at two locations on opposite longitudinal ends with fixing screws 2830c. The developing roller 2806 includes a metal core rod 2806c and a rubber portion 2806d.

[0205] The developing roller 2806 is rotatably supported by a driving side bearing 2826 and a non-driving side bearing 2827 attached to opposite longitudinal ends of the developing frame 2825. Fig.30 As shown, a developing drive input gear 2832 for transmitting a driving force to the developing unit 2809 is provided at one longitudinal end of the developing unit 2809. The developing drive input gear 2832 includes a main developing drive coupling member 2885 (see FIG. 28) connected to the main body 2870 of the imaging device. Fig.26 The driving force of the driving motor (not shown) of the imaging device body 2870 is input to the developing unit 2809 through the developing input coupling part 2832a, the developing drive input gear 2832, and the like.

[0206] The driving force input to the developing unit 2809 is transmitted to the developing roller gear 2831, so that the developing roller 2806 moves along the Fig.24Rotate in the direction of arrow D. Fig.29 As shown, a developing cover member 2828 supporting and covering the developing drive input gear 2832 is provided at one longitudinal end of the developing unit 2809. The developing roller 2806 has a smaller outer diameter than the photosensitive drum 2804. In the present embodiment, the outer diameter of the photosensitive drum 2804 is in the range of Φ18 to Φ22, and the outer diameter of the developing roller 2806 is in the range of Φ8 to Φ14. These outer diameters allow for efficient placement.

[0207] Drum unit and developer unit connection

[0208] Reference Fig.30 , the connection of the drum unit 2808 and the developing unit 2809 will now be described. The drum unit 2808 and the developing unit 2809 are connected by a driving side cover member 2816 and a non-driving side cover member 2817 provided at opposite ends of the process cartridge 2800 in the longitudinal direction.

[0209] The driving side cover member 2816 disposed at one longitudinal end of the process cartridge 2800 has a developing unit support hole 2816a for pivotally (movably) supporting the developing unit 2809. Similarly, the non-driving side cover member 2817 disposed at the other longitudinal end of the process cartridge 2800 has a developing unit support hole 2817a for pivotally supporting the developing unit 2809. The driving side cover member 2816 and the non-driving side cover member 2817 have drum support holes 2816b and 2817b for rotatably supporting the photosensitive drum 2804.

[0210] At one end, the outer peripheral portion of the cylindrical portion 2828b of the developer cover member 2828 is assembled in the developer unit support hole 2816a of the drive side box cover member 2816. At the other end, the outer peripheral portion of the cylindrical portion (not shown) of the non-drive side bearing 2827 is assembled in the developer unit support hole 2817a of the non-drive side box cover member 2817. The longitudinal ends of the photosensitive drum 2804 are assembled in the drum support hole 2816b of the drive side box cover member 2816 and the drum support hole 2817b of the non-drive side box cover member 2817. Then, the drive side box cover member 2816 and the non-drive side box cover member 2817 are fixed to the drum unit 2808, for example, with screws or adhesive (not shown) etc. As a result, the developer unit 2809 is supported by the drive side box cover member 2816 and the non-drive side box cover member 2817 in a manner that rotates relative to the drum unit 2808 (photosensitive drum 2804). Therefore, the developer roller 2806 is positioned at a position where the developer roller 2806 acts on the photosensitive drum 2804 during imaging.

[0211] Fig.31The drum unit 2808 and the developing unit 2809 are shown to be connected together and integrally formed into the state of the process cartridge 2800 by the above steps. The axis connecting the center of the developing unit support hole 2816a of the driving side box cover component 2816 and the center of the developing unit support hole 2817a of the non-driving side box cover component 2817 is called the pivot axis K. The cylindrical portion 2828b at one end of the developing cover component 2828 is coaxial with the developing input coupling 2774. That is, the developing unit 2809 is configured to receive the driving force transmitted from the imaging device main body 2870 along the pivot axis K. And the developing unit 2809 is supported in a manner rotating around the pivot axis K.

[0212] Structure of power supply part of process cartridge

[0213] Reference Figures 32A to 32D , the configuration of the power supply portion of this embodiment will now be described. Fig.32A 28 is a perspective view of the area around the portion of the drum unit 2808 that is connected to the non-driving side cartridge cover member 2817. Fig.32A , only the electrode component 2860 is shown in an exploded view. Fig.32B is a cross-sectional view of the electrode component 2860. Fig.32C It is along Fig.32A The cross-sectional view taken along line FF in FIG. Fig.32A The state where the middle electrode part 2860 is fixed. Fig.32D It is along Fig.32A The cross-sectional view taken along line JJ in FIG. Fig.32A The state where the middle electrode part 2860 is fixed.

[0214] In the drum frame 2815 as the first frame, a conductive resin 2818 is integrally formed in the drum frame 2815 by two-color molding. The conductive resin 2818 has a surface 2818a in contact with the electrode member 2860 and a surface 2818b as a seating surface of the pressing spring 2821b. As in the first embodiment, the drum frame as the first frame has a conductivity of about 0.95 to 1.10 g / cm 3 The density and flame retardant performance is HB according to UL94 standard.

[0215] The electrode member 2860 is made of a stainless steel material having a thickness of about 0.2 mm. The electrode member 2860 has an embossed contact portion 2860c that contacts the surface 2818a of the conductive resin 2818 and an embossed contact portion 2860c that contacts the electrode spring 2893 ( Fig.33B and 33C ) contacts and receives the contact surface 2860d of the electric power. The electrode spring 2893 supplies the electric power from the imaging device main body 2870. The non-driving side cartridge cover member 2817 as a second frame supports the electrode member 2860.

[0216] The non-driving side cover member 2817 as the second frame has a g / cm 3 The electrode member 2860 has a positioning portion 2860a into which the boss 2817c of the non-driving side cover member 2817 is fitted, and a protruding cutting portion 2860b engaged with a surface 2817d of the boss 2817c, and is thus fixed ( Fig.32C ).

[0217] like Fig.32B As shown, the side of the electrode component 2860 including the contact portion 2860c is bent about 3° in the direction of the conductive resin 2818 relative to the placement surface 2860e provided on the non-driving side cover component 2817. This is to prevent the contact portion 2860c of the electrode component 2860 from being separated from the surface 2818a of the conductive resin 2818 when the electrode component 2860 is coupled to the non-driving side cover component 2817. Since the side including the contact portion 2860c is bent in the direction of the surface 2818a of the conductive resin 2818 that penetrates, when the electrode component 2860 is coupled to the non-driving side cover component 2817, the contact portion 2860c contacts the surface 2818a of the conductive resin 2818 under a certain pressure. Therefore, even if there is a size change in the conductive resin 2818, the non-drive side cover member 2817 and the electrode member 2860, the surface 2818a of the conductive resin 2818 and the contact portion 2860c of the electrode member 2860 are always in contact with each other. This prevents the conduction failure that would otherwise be caused by the contact failure between the electrode member 2860 and the conductive resin 2818 and the ignition caused by the tracking.

[0218] The voltage supplied from the contact spring 2893 to the electrode member 2860 is supplied to the charging roller 2805 via the conductive resin 2818 (which is formed in the drum frame 2815 by two-color molding), the pressing spring 2821b, and the non-driving side charging roller bearing 2820b.

[0219] Conductive resin 2818 is formed by two-color molding in the above-mentioned structure, but it can be formed as a separate component and fixed to drum frame 2815 as the first frame. Moreover, in the above-mentioned structure, electrode component 2860 is fixed by protruding cutting portion 2860b, but electrode component 2860 can be fixed using screws or caulking agent. In addition, the side including contact portion 2860c of electrode component 2860 is curved relative to placement surface 2860e, but the structure is not limited to this. The thickness of electrode component 2860 can be increased to form a deep embossed shape, so that electrode component 2860 is always in contact with surface 2818a of conductive resin 2818.

[0220] Structure of power supply part of imaging device main body and process cartridge

[0221] Reference Fig.25 , 33A , 33B and 33C, the structure of the power supply portion including the imaging device main body 2870 is now described. Fig.33A 28. It is a perspective view of the process cartridge in a state where the storage element communication unit 2890 and the contact spring holding member 2892 are lowered. Fig.33B It is along Fig.33A An enlarged cross-sectional view of the power supply portion taken along line VV in FIG. Fig.33C It is along Fig.33A An enlarged cross-sectional view of the power supply portion taken along line NN in FIG.

[0222] The image forming apparatus body 2870 includes a contact spring holding member 2892 and holds a contact spring 2893 for supplying power to the process cartridge 2800. The contact spring holding member 2892 is fixed to a storage element communication unit 2890 that communicates with a storage element (not shown) provided in the process cartridge 2800.

[0223] Fig.25 The linkage between the front door 2711 shown in FIG. 2 and the linkage mechanism (not shown) can move the contact spring 2893 and the electrode member 2860 into and out of contact with each other. Closing the front door 2711 causes the storage element communication unit 2890 and the contact spring holding member 2892 to move along the arrow Z2 ( Fig.33B ) direction. Opening the front door 2711 causes the storage element communication unit 2890 and the contact spring holding member 2892 to be lifted in the direction of the arrow Z1. That is, closing the front door 2711 causes the contact spring 2893 and the electrode member 2860 to contact each other, while opening the front door 2711 causes the contact spring 2893 and the electrode member 2860 to be separated from each other. The flame retardant performance of the contact spring holding member 2892 is V-1 according to the UL94 standard.

[0224] like Fig.33B As shown, the protrusion 2817f protrudes from the non-driving side cover component 2817 in the direction of arrow Z1 at opposite sides (in the directions of arrows X1 and X2) of the electrode component 2860. The height H1 of the protrusion 2817f is set to be higher than the contact surface 2860d between the contact spring 2893 and the electrode component 2860 in the Z1 direction. In order to reduce the fire spread range Q generated when a fire occurs between the contact spring 2893 and the electrode component 2860 due to tracking, the protrusion 2817f is preferably located near the contact spring 2893 and the electrode component 2860. The fire spreads upward, and the non-driving side cover component 2817, which is made of V-1 material and is self-extinguishing, does not burn. Therefore, the fire spread range Q in the X1 and X2 directions is as shown in FIG. Fig.33B As shown in Q.

[0225] like Fig.33C As shown, at the side corresponding to the side of arrow Y1 in the longitudinal direction of the electrode part 2860, there is arranged a protrusion 2817g integrally connected to the end in the Y1 direction of the protrusion 2817f of the non-driving side cover part 2817. The height H2 of the protrusion 2817g is set to be higher than the contact surface 2860d between the contact spring 2893 and the electrode part 2860 in the Z1 direction. In order to reduce the fire spread range R in the same manner as the X1 and X2 directions, the protrusion 2817g is preferably located near the contact spring 2893 and the electrode part 2860. As described above with respect to the X1 and X2 directions, the fire spreads upward, and the non-driving side cover part 2817, which is made of V-1 material and is self-extinguishing, does not burn. Therefore, the fire spread range R in the Y1 and Y2 directions is as shown in FIG. Fig.33C As shown in the “R” in the figure.

[0226] Furthermore, the protruding portions 2892a and 2892b also extend in the longitudinal direction from the contact spring holding member 2892. The protruding portions 2892a and 2892b are set to hinder the fire spreading range R.

[0227] Now describe the situation in which a fire is caused due to tracking between the contact spring 2893 and the electrode component 2860. When a fire occurs between the contact spring 2893 and the electrode component 2860, the fire may spread on the fire spread range Q and R. However, since the contact spring retaining component 2892 located above the ignition point (in the Z1 direction) and the non-driving side box cover 2817 located in the longitudinal direction (Y1 and Y2 directions) and the front-back direction (X1 and X2 directions) of the ignition point have a flame retardant performance of V-1 and are self-extinguishing, the fire will not spread. On the contrary, when the protruding parts 2817f and 2817g are not provided, the fire will spread on the fire spread range Q' and R'. The lack of components that limit the spread of fire may cause the fire to spread to the developing frame 2825 made of the HB material with lower flame retardant performance. In contrast, since the flame retardant performance of the protruding portions 2817f and 2817g of the non-drive side box cover component 2817 and the protruding portions 2892a and 2892b of the contact spring retaining component 2892 within the fire spread range of this embodiment is V-1, the fire will not spread to components with low flame retardant performance.

[0228] As mentioned above, the projection 2817f and 2817g of non-driving side box cover component 2817 are arranged around electrode component 2860, and the contact spring holding component 2892 with projection 2892a and 2892b is arranged above the fire spreading range.In addition, non-driving side box cover component 2817 and contact spring holding component 2892 are made of the material that is V-1 according to UL94 standard flame retardant performance.Therefore, even owing to tracing and catching fire, fire also can not spread to the parts with low flame retardant performance.Therefore, the processing box and imaging device that guarantee safety can be provided.

[0229] In the present embodiment, the protruding portion of the non-drive side cover component 2817 surrounds the electrode component 2860, but the structure is not limited thereto. The protruding portion can protrude from the contact spring holding component 2892 in the Z2 direction and surround the electrode component 2860. In the present embodiment, the non-drive side cover component 2817 and the contact spring holding component 2892 have a flame retardant performance of V-1 according to the UL94 standard, but these components can have a flame retardant performance of more than V-1.

[0230] The process cartridge construction and drum cartridge construction of the first to third embodiments can achieve the same weight reduction and fire spread prevention effects in a structure in which these constructions are attached to the device body of the imaging device in an undetachable manner. As such, the process cartridge construction and drum cartridge construction of the first to third embodiments are applicable to a structure in which these constructions are attached to the imaging device in an undetachable manner.

[0231] In such a configuration, the use of HB material (which is a low-density resin material) reduces the overall weight of the imaging device, while achieving safety and weight reduction of the imaging device. Therefore, the impact value of the imaging device body during logistics can be reduced. This allows the packaging of the imaging device to be smaller, thereby improving logistics efficiency.

[0232] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. A processing unit for a device body of an imaging device, the processing unit comprising: a processing component to be used to form an image; a first component comprising a first resin material; a second component including a second resin material having higher flame retardancy than the first resin material; and an electrode component including a contact portion configured to supply power from the device body, the electrode component being configured to be electrically connected to the processing component, wherein The first component is part of a frame of the processing unit; the second resin material of the second component has a greater density than the first resin material of the first component, and At least a portion of the second member is located closer to the contact portion than a portion of the first member closest to the contact portion and between the contact portion and the portion of the first member closest to the contact portion.

2. A processing unit for a device body of an imaging device, the processing unit comprising: a processing component to be used to form an image; a first component comprising a first resin material; a second component including a second resin material having higher flame retardancy than the first resin material; and an electrode component including a contact portion configured to supply power from the device body, the electrode component being configured to be electrically connected to the processing component, wherein The first component is part of a frame of the processing unit; the second resin material of the second component has a greater density than the first resin material of the first component, and The contact portion is supported by the second member.

3. The processing unit according to claim 1 or 2, in, The second component comprises: an electrode mounting surface on which the electrode assembly is located; and A protruding portion that protrudes from the electrode placement surface in a direction perpendicular to the electrode placement surface.

4. The processing unit according to claim 1 or 2, wherein The processing unit includes a third component integrally coupled to the first component and containing a second resin material having a higher flame retardant property than the first resin material; The second member includes an electrode mounting surface on which the electrode member is located; and The third member includes a protruding portion that protrudes beyond the electrode mounting surface in a direction perpendicular to the electrode mounting surface.

5. The processing unit according to claim 3, in, The protruding portion is positioned to block the space between the electrode mounting surface and the first member.

6. The processing unit according to claim 3, in, The protruding portion protrudes in such a manner as to surround the outer circumference of the electrode placement surface.

7. The processing unit according to claim 3, further comprising a fourth member containing the first resin material, in, The protruding portion is positioned to block a space between the electrode seating surface and the fourth member.

8. The processing unit according to claim 1 or 2, in, The first resin material and the second resin material have different flame retardant grades according to the UL94 standard.

9. The processing unit according to claim 8, wherein: The first resin material is a resin material having a flame retardant property of HB according to the UL94 standard, and The second resin material is a resin material having a flame retardancy of V-1 according to the UL94 standard.

10. The processing unit according to claim 1 or 2, in, The electrode member includes a conductive resin material.

11. The processing unit according to claim 10, wherein The processing component is a rotating component; The second member and the electrode member are formed integrally with each other and are a bearing member that rotatably supports the processing member; Electrode components include: a shaft support portion configured to supply power to the processing component; A connecting portion connecting the contact portion to the shaft supporting portion; and A gate portion for injecting resin during the molding process; and When viewed from a direction perpendicular to a plane of the contact portion, the connection portion and the gate portion are included in the contact portion, and the shaft support portion overlaps at least a portion of the contact portion.

12. The processing unit according to claim 11, wherein The shaft support portion is cylindrical, and The second member includes an inner peripheral support portion that supports an inner periphery of the shaft support portion, and an outer peripheral support portion that supports an outer periphery of the shaft support portion.

13. The processing unit according to claim 1 or 2, in, The electrode parts contain metal materials.

14. The processing unit according to claim 1 or 2, in, The process unit is any one of an image bearing member, a developer bearing member, and a charging member.

15. The processing unit according to claim 1 or 2, in, The processing unit is attachable to and detachable from the device main body.

16. The processing unit according to claim 1 or 2, in, The first member supports the processing member.

17. The processing unit according to claim 1 or 2, in, The second component is integrally coupled to the first component.

18. The processing unit according to claim 1 or 2, in, The electrode member is coupled in such a manner as to be in contact with at least the second member.

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