Developing unit

Abstract

To provide a technique that can ensure sealing properties at the boundary of seal members stably at a low cost even if there is a variation in the pasting position of the seal member.SOLUTION: A developing unit comprises a sealing member that is charged into a space surrounded by a frame body 120, a regulation member 130, a first seal member 160, and a second seal member 200, and communicating a developer storage chamber of the frame body 120 and the outside. A wall surface of the frame body 120 has a first attachment surface 121a to which the first seal member 160 is attached, a second attachment surface 121b to which an end of a support part 130a of the regulation member 130 is attached, and a third attachment surface 121h to which the second seal member 200 is attached, and an area between the attachment surfaces is a concave part recessed with respect to the attachment surfaces. In the concave part, an area extending from between the first attachment surface 121a and the second attachment surface 121b to the third attachment surface 121h includes inclined surfaces 121c, 121d inclined with respect to the second attachment surface 121b.SELECTED DRAWING: Figure 20

Description

Technical Field

[0001] The present disclosure relates to a developing unit provided in an image forming apparatus such as a copying machine or a printer that employs an electrophotographic method.

Background Art

[0002] An image forming apparatus such as a copying machine or a printer that employs an electrophotographic method includes a developing unit for developing an electrostatic latent image formed on a photosensitive drum as an image carrier into a toner image. The developing unit includes a developing container (frame) having an accommodation chamber for accommodating toner as a developer, a developer carrier (developing roller) for carrying and transporting the toner accommodated in the developing container, and a layer thickness regulating member (developing blade) for regulating the toner layer thickness on the developing roller. To prevent the toner accommodated in the developing container from leaking to the outside of the developing unit through these respective constituent members, the developing unit is configured to be sealed with a plurality of seal members or the like.

[0003] As a sealing configuration using a seal member, various seal members are arranged so as to cover the periphery of the toner supply opening of the developing container. An elastic developing blade lower seal member such as foamed polyurethane foam is arranged in the gap between the developing container and the developing blade. Further, at both longitudinal ends of the developing container, flexible end seal members or the like formed of felt or the like on the surface that rubs against the developing roller are arranged in the gaps between the developing container and the back surface of the developing blade and the circumferential surface of the developing roller.

[0004] Patent Document 1 discloses that, at the seal portion between the developing blade lower seal member and the end seal member at both longitudinal ends of the developing container, convex portions are provided at both ends of the developing blade lower seal member, and the convex portions are pressed against and crushed on the side surface of the end seal member. With such a configuration, the adhesion of the joint portion (boundary portion) between the seal members is enhanced to prevent toner from leaking between the seal members.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the above prior art, in order to reliably press the seal members against each other, the pasting accuracy of the seal members is important, and it is necessary to perform the pasting operation accurately by hand.

[0007] An object of the present invention is to provide a technique capable of stably and at low cost ensuring the sealing performance at the boundary between each seal member even when there is variation in the pasting position of the seal members.

Means for Solving the Problems

[0008] To achieve the above object, the developing unit of the present invention includes a frame body having a storage chamber for storing a developer and an opening communicating with the storage chamber, a developing roller supported by the frame body so as to face the opening and rotatably supported about a rotation axis, a regulating member for regulating the layer thickness of the developer carried on the outer peripheral surface of the developing roller, the regulating member being arranged along the direction of the rotation axis of the developing roller in a region on the downstream side in the rotation direction of the developing roller among the edge portions of the opening, and having a support portion whose end portion in the direction of the rotation axis is fixed to the frame body, and a sliding portion supported by the support portion and in sliding contact with the outer peripheral surface of the developing roller on the upstream side in the rotation direction with respect to the support portion, a regulating member having a sliding portion; a first seal member provided along the direction of the rotation axis so as to seal between the region on the downstream side among the edge portions of the opening and the support portion of the regulating member, a second seal member provided along the rotation direction in a region outside the opening in the direction of the rotation axis and in sliding contact with an end portion of the outer peripheral surface of the developing roller in the direction of the rotation axis. A developing unit comprising: wherein the frame body has a first mounting surface to which the first seal member is attached; a second mounting surface provided at a position spaced apart from the first mounting surface in the direction of the rotation axis, to which the end portion of the support portion is attached; a third mounting surface provided at a position spaced upstream in the rotation direction from the first mounting surface and the second mounting surface in the rotation direction, to which the second seal member is attached; and has the second seal member sandwiches the end portion of the sliding portion of the restricting member on the rotation axis together with the developing roller; the first seal member is attached to the first mounting surface so as to be spaced apart from each of the second mounting surface, the third mounting surface, and the second seal member; and the second seal member is attached to the third mounting surface so as to be spaced apart from each of the support portion of the restricting member, the first seal member, the first mounting surface, and the second mounting surface; a space surrounded by the frame body, the restricting member, the first seal member, and the second seal member, and a space communicating between the storage chamber and the outside of the frame body through the opening is formed; comprising a sealing member filled in the space; Among the wall surfaces of the frame body forming the space, the region between the first mounting surface, the second mounting surface, and the third mounting surface is a concave portion recessed with respect to each of the first mounting surface, the second mounting surface, and the third mounting surface, and the region from the region between the first mounting surface and the second mounting surface to the third mounting surface in the concave portion includes an inclined surface inclined with respect to the second mounting surface.

Advantages of the Invention

[0009] According to the present invention, it is possible to stably and inexpensively ensure the sealing performance at the boundary portion between the seal members without being affected by the assembling accuracy of the seal members.

Brief Description of the Drawings

[0010]

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[0011] In the following examples, the embodiments in the present disclosure will be illustratively described. However, the configurations disclosed in the following examples, for example, the functions, materials, shapes, and relative arrangements of the components, show an example of the form related to the scope of the claims, and are not intended to limit the scope of the claims to the configurations disclosed in these examples. Also, the problems solved by the configurations disclosed in the following examples or the actions or effects obtained from the disclosed configurations are not intended to limit the scope of the claims.

[0012] (Example 1) Hereinafter, an electrophotographic image forming apparatus according to Example 1 of the present disclosure will be described with reference to the drawings. Here, the electrophotographic image forming apparatus (hereinafter, the image forming apparatus) is an apparatus that forms an image on a recording material using the electrophotographic image forming method. Examples of the image forming apparatus include a copying machine, a facsimile apparatus, a printer (laser beam printer, LED printer, etc.), and a multifunction machine (multifunction printer) thereof. Examples of the recording material include sheet-like recording media such as recording paper and plastic sheets. Further, the image forming apparatus according to the present embodiment is an image forming apparatus that employs a so-called cartridge system. A cartridge is a unit that can be attached to and detached from the image forming apparatus, and is a unit having a photoreceptor and process means (for example, a charging member, a developing member, a cleaning member, etc.) that act on the photoreceptor. In the following examples, a laser beam printer to which four process cartridges (cartridges) can be attached and detached is illustrated as the image forming apparatus. Note that the number of process cartridges attached to the image forming apparatus is not limited to this and may be appropriately set as needed.

[0013] [Schematic Configuration of Image Forming Apparatus] FIG. 1 is a cross-sectional view schematically showing the configuration of the image forming apparatus M according to the present embodiment. Further, FIG. 2 is a cross-sectional view schematically showing the configuration of the process cartridge 100. This 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 S. The image forming apparatus M uses a process cartridge system, and the process cartridge 100 is detachably mounted on the image forming apparatus main body (apparatus main body) 170 to form a color image on the recording medium S.

[0014] Here, with respect to the image forming apparatus M, the side provided with the front door 11 is defined as the front (front surface), and the surface opposite to the front is defined as the back (rear surface). Further, when viewing the image forming apparatus M from the front, the right side is referred to as the drive side, and the left side is referred to as the non-drive side. Also, when viewing the image forming apparatus M from the front, the upper side is defined as the upper surface, and the lower side is defined as the lower surface. FIG. 1 is a cross-sectional view of the image forming apparatus M viewed from the non-drive side, with the near side of the paper being the non-drive side of the image forming apparatus M, the right side of the paper being the front of the image forming apparatus M, and the far side of the paper being the drive side of the image forming apparatus M.

[0015] Also, the drive side of the process cartridge 100 is the side on which a drum coupling member (photosensitive member coupling member), which will be described later, is arranged with respect to the axis direction of the photosensitive drum (the axis direction of the rotation axis of the photosensitive drum). Also, the drive side of the process cartridge 100 is the side on which a developing coupling portion 132a, which will be described later, is arranged with respect to the axis direction of the developing roller (developing member) (the axis direction of the rotation axis of the developing roller). Note that the axis direction of the photosensitive drum and the axis direction of the developing roller are parallel, and the longitudinal direction of the process cartridge 100 is also parallel to these.

[0016] Four process cartridges 100 (100Y, 100M, 100C, 100K) are arranged in a substantially horizontal direction in the apparatus main body 170 (hereinafter, the apparatus main body 170). That is, they are the four process cartridges: the first process cartridge 100Y, the second process cartridge 100M, the third process cartridge 100C, and the fourth process cartridge 100K.

[0017] Each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) has the same electrophotographic process mechanism, and the colors of the developer (hereinafter referred to as toner) are different from each other. A rotational driving force is transmitted to the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) from a driving output section of the apparatus main body 170 (details will be described later). Further, a bias voltage (such as a charging bias and a developing bias) is supplied to each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) from the apparatus main body 170.

[0018] As shown in FIG. 2, each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) of the present embodiment has a drum unit 108 including a photosensitive drum 104 and a charging unit as a process means acting on the photosensitive drum 104. Here, the drum unit 108 may have not only a charging unit but also a cleaning unit as a process means. Further, each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) has a developing unit 109 including a developing means for developing an electrostatic latent image on the photosensitive drum 104. Such a layout of an electrophotographic image forming apparatus in which a plurality of photosensitive drums 104 are arranged substantially in a line may be referred to as an in-line layout or a tandem layout.

[0019] In each of the first to fourth process cartridges 100, the drum unit 108 and the developing unit 109 are coupled to each other. A more specific configuration of the process cartridge 100 will be described later.

[0020] The first process cartridge 100Y contains yellow (Y) toner in the developer container 120 and forms a yellow toner image on the surface of the photosensitive drum 104. The second process cartridge 100M contains magenta (M) toner in the developer container 120 and forms a magenta toner image on the surface of the photosensitive drum 104. The third process cartridge 100C contains cyan (C) toner in the developer container 120 and forms a cyan toner image on the surface of the photosensitive drum 104. The fourth process cartridge 100K contains black (K) toner in the developer container 120 and forms a black toner image on the surface of the photosensitive drum 104.

[0021] As shown in FIG. 1, a laser scanner unit 14 serving as an exposure means is provided above the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K). The laser scanner unit 14 outputs a laser beam U corresponding to image information. The laser beam U passes through an exposure window 110 (see FIG. 2) of the process cartridge 100 and scans and exposes the surface of the photosensitive drum 104.

[0022] An intermediate transfer unit 12 serving as a transfer member is provided below the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K). The process cartridge 12 has a drive roller 12e, a turn roller 12c, and a tension roller 12b, around which a flexible transfer belt 12a is stretched. The lower region of the circumferential surface of the photosensitive drum 104 of each of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) contacts an upper region of the outer circumferential surface of the annular transfer belt 12a. This contact area is the primary transfer area. A primary transfer roller 12d is provided inside the transfer belt 12a, facing the photosensitive drum 104. A secondary transfer roller 6 is in contact with the turn roller 12c via the transfer belt 12a. The contact area between the transfer belt 12a and the secondary transfer roller 6 is the secondary transfer area.

[0023] Below the intermediate transfer unit 12, a paper feed unit 4 is provided. This paper feed unit 4 has a paper feed tray 4a for loading and accommodating the recording medium S and a paper feed roller 4b. The conveyance path of the recording medium S is configured to go substantially upward from the paper feed unit 4 on the back side of the apparatus main body 170 within the apparatus main body 170.

[0024] On the downstream side of the secondary transfer unit in the conveyance path of the recording medium S (upper left within the apparatus main body 170 in FIG. 1), a fixing device 7 and a paper discharge device 8 are provided. The upper surface of the apparatus main body 170 serves as a paper discharge tray 13. The recording medium S is heated and pressurized by the fixing means provided in the fixing device 7 to fix the toner image and is discharged to the paper discharge tray 13.

[0025] [Image forming operation] The operations for forming a full-color image are as follows. The photosensitive drums 104 of the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) are rotationally driven at a predetermined speed (in the direction of arrow A in FIG. 2). The transfer belt 12a is also rotationally driven in the forward direction (in the direction of arrow C in FIG. 1) at a speed corresponding to the speed of the photosensitive drum 104 in accordance with the rotation of the photosensitive drum 104.

[0026] The laser scanner unit 14 is also driven. In synchronization with the driving of the laser scanner unit 14, the charging roller 105 in each process cartridge 100 uniformly charges the surface of the photosensitive drum 104 to a predetermined polarity and potential. The laser scanner unit 14 scans and exposes the surface of each photosensitive drum 104 with laser light U according to the image signals of each color. Thereby, an electrostatic latent image corresponding to the image signal of the corresponding color is formed on the surface of each photosensitive drum 104. The formed electrostatic latent image is developed by a developing roller 106 that is rotationally driven at a predetermined speed. By such an electrophotographic image forming process operation, a yellow toner image corresponding to the yellow component of the full-color image is formed on the photosensitive drum 104 of the first process cartridge 100Y. Then, the toner image is primarily transferred onto the transfer belt 12a.

[0027] Similarly, on the photosensitive drum 104 of the second process cartridge 100M, a magenta toner image corresponding to the magenta component of the full-color image is formed. Then, the toner image is superimposed on the yellow toner image already transferred onto the transfer belt 12a and is primarily transferred. Similarly, on the photosensitive drum 104 of the third process cartridge 100C, a cyan toner image corresponding to the cyan component of the full-color image is formed. Then, the toner image is superimposed on the yellow and magenta toner images already transferred onto the transfer belt 12a and is primarily transferred. Similarly, on the photosensitive drum 104 of the fourth process cartridge 100K, a black toner image corresponding to the black component of the full-color image is formed. Then, the toner image is superimposed on the yellow, magenta, and cyan toner images already transferred onto the transfer belt 12a and is primarily transferred. In this way, an unfixed toner image of four-color full color, i.e., yellow, magenta, cyan, and black, is formed on the transfer belt 12a.

[0028] On the other hand, the recording media S are separated and fed one by one at a predetermined control timing. The recording media S are introduced into the secondary transfer section, which is the contact section between the secondary transfer roller 6 and the transfer belt 12a, at a predetermined control timing. As a result, in the process of transporting the recording media S to the secondary transfer section, the four-color superimposed toner image on the transfer belt 12a is sequentially batch-transferred onto the surface of the recording media S. After that, the recording media S are transported to the fixing device 7 to fix the toner image on the recording media S, and then further discharged to the paper discharge tray 13.

[0029] [Schematic of the Process Cartridge Detachable Configuration] Using FIGS. 1, 3 to 6, the tray 171 (hereinafter referred to as the tray) that supports the process cartridge will be described in more detail. FIG. 3 is a cross-sectional view of the image forming apparatus M in which the tray 171 is located inside the apparatus main body 170 with the front door 11 open. FIG. 4 is a cross-sectional view of the image forming apparatus M in which the tray 171 is located outside the apparatus main body 170 with the front door 11 open and the process cartridge 100 is housed inside the tray 171. FIG. 5 is a cross-sectional view of the image forming apparatus M in which the tray 171 is located outside the apparatus main body 170 with the front door 11 open and the process cartridge 100 is removed from the tray 171. FIG. 6(a) is a partial detailed view of the tray 171 viewed from the drive side in the state of FIG. 3. FIG. 6(b) is a partial detailed view of the tray 171 viewed from the non-drive side in the state of FIG. 3.

[0030] As shown in FIGS. 3 and 4, the tray 171 is movable with respect to the apparatus main body 170 in the direction of arrow X1 (push-in direction) and arrow X2 (pull-out direction), which are the front-rear direction of the apparatus. That is, the tray 171 is provided so as to be pullable and pushable with respect to the apparatus main body 170, and in a state where the apparatus main body 170 is installed on a horizontal plane, the tray 171 is configured to be movable in a substantially horizontal direction. Here, the state where the tray 171 is located outside the apparatus main body 170 (the state of FIG. 4) is referred to as the outer position. Also, the state where the tray 171 is located inside the apparatus main body 170 with the front door 11 open and the photosensitive drum 104 and the transfer belt 12a are separated (the state of FIG. 3) is referred to as the inner position.

[0031] Further, the tray 171 has a mounting portion 171a at the outer position that can removably mount the process cartridge 100 as shown in FIG. 5. And each process cartridge 100 mounted on the mounting portion 171a at the outer position of the tray 171, as shown in FIG. 6, includes a drive-side cartridge cover member 116 and a non- driveIt is supported by the moving-side cartridge cover member 117 on the tray 171. Then, the process cartridge 100 moves inside the apparatus main body 170 together with the movement of the tray 171 while being disposed in the mounting portion 171a. At this time, it moves with a gap between the transfer belt 12a and the photosensitive drum 104. For this reason, the photosensitive drum 104 does not come into contact with the transfer belt 12a, and the tray 171 can move the process cartridge 100 inside the apparatus main body 170 (details will be described later).

[0032] As described above, the tray 171 can move a plurality of process cartridges 100 together to a position where image formation is possible inside the apparatus main body 170, and can also pull them out together to the outside of the apparatus main body 170.

[0033] [Positioning of Process Cartridge] Using FIGS. 6(a) and 6(b), the positioning of the process cartridge 100 to the apparatus main body 170 will be described in more detail. As shown in FIGS. 6(a) and 6(b), the tray 171 has a right-side tray portion 171R that supports the drive side (right side in the longitudinal direction) of the process cartridge 100 and a left-side tray portion 171L that supports the non-drive side (left side in the longitudinal direction). Positioning portions 171VR and 171VL for holding the cartridge 100 are provided on the right-side tray portion 171R and the left-side tray portion 171L, respectively. The positioning portion 171VR has straight portions 171VR1 and 171VR2.

[0034] As shown in FIG. 6(a), the arc portions 116VR1 and 116VR2 of the cartridge cover member 116 come into contact with the aforementioned straight portions 171VR1 and 171VR2, so that the photosensitive drum center is determined. Also, as shown in FIG. 6(a), the right-side tray portion 171R has a rotation-determining convex portion 171KR. As shown in FIG. 6(a), when the rotation-determining convex portion 171KR fits into the rotation-determining concave portion 116KR of the cartridge cover member 116, the posture of the process cartridge 100 is determined with respect to the apparatus main body 170.

[0035] The positioning part 171VR and the positioning part 171VL and the rotation determining convex part 171KL are arranged at positions (non-driving side) facing each other with the intermediate transfer belt 12a sandwiched therebetween in the longitudinal direction of the process cartridge 100. The positioning part 171VL has straight parts 171VL1 and 171VL2. As shown in Fig. 6(b), non-driving side the arc parts 117VL1 and 117VL2 of the cartridge cover member 117 come into contact with the aforementioned straight parts 171VL1 and 171VL2, so that the center of the photosensitive drum is determined. Also, as shown in Fig. 6(b), the left tray part 171L has a rotation determining convex part 171KL. As shown in Fig. 6(b), the rotation determining convex part 171KL non-driving side fits with the rotation determining concave part 117KL of the cartridge cover member 117, so that the posture of the process cartridge 100 with respect to the apparatus main body 170 is determined.

[0036] With the above configuration, the position of the process cartridge 100 with respect to the tray 171 is correctly determined. Then, as shown in Fig. 4, the process cartridge 100 integrated with the tray 171 is moved in the direction of arrow X1 and inserted to the position shown in Fig. 3. Then, by closing the front door 11 in the direction of arrow R, the process cartridge to 100 is pressed by a cartridge pressing mechanism (not shown) described later and fixed to the apparatus main body 170 together with the tray 171. Also, in conjunction with the operation of the cartridge pressing mechanism, the transfer belt 12a comes into contact with the photosensitive photosensitive drum 10 as member 4. When this state is reached, an image forming state is achieved (Fig. 1).

[0037] In this embodiment, the positioning part 171VR and the positioning part 171VL also serve as a reinforcement for maintaining the rigidity in the drawing operation of the tray 171, and thus a metal sheet metal is used, but it is not limited thereto.

[0038] [Cartridge Pressing Mechanism] With reference to FIGS. 7 and 13, the details of the cartridge pressing mechanism will be described. FIG. 7(a) is a perspective view showing only the process cartridge 100, the tray 171, the cartridge pressing mechanisms 190 and 191, and the intermediate transfer unit 12 in a state where the front door 11 is opened as shown in FIG. 3. FIG. 7(b) is a perspective view showing only the process cartridge 100, the tray 171, the cartridge pressing mechanisms 190 and 191, and the intermediate transfer unit 12 in a state where the front door 11 is closed as shown in FIG. 1.

[0039] Here, the process cartridge 100 receives a driving force during image formation and further receives a reaction force from the primary transfer roller 12d (FIG. 1) in the direction of arrow Z1. Therefore, in order for the process cartridge to maintain a stable posture without floating from the positioning portions 171VR and 171VL (see FIG. 6) during the image forming operation, it is necessary to press the process cartridge in the Z2 direction. To achieve this, in the present embodiment, a cartridge pressing mechanism (190, 191) is provided in the apparatus main body 170. The cartridge pressing mechanism (190, 191) is composed of a memory element pressing unit 190 on the non-driving side and a cartridge pressing unit 191 on the driving side, which will be described in more detail below.

[0040] When the front door 11 is closed as shown in FIG. 3, the memory element pressing unit 190 and the cartridge pressing unit 191 shown in FIG. 7 descend in the direction of arrow Z2. The memory element pressing unit 190 mainly has a main body side electrical contact (not shown) that contacts an electrical contact (not shown) of a memory element (not shown) provided in the process cartridge 100. The front door 11 and a link mechanism (not shown) By being interlocked with [the relevant component], it is configured such that the memory element 140 can be brought into contact with and separated from the main body side electrical contact. That is, when the front door 11 is closed, the contact comes into contact, and when the front door 11 is opened, the contact separates. With such a configuration, when the process cartridge 100 moves inside the image forming apparatus main body together with the tray 171, the electrical contact is not rubbed, and by retracting the contact from the insertion and removal trajectory of the process cartridge 100, the insertion and removal of the tray 171 is not hindered. This memory element pressing unit 190 also serves to press the process cartridge 100 against the aforementioned positioning portion 171VR. Similarly to the memory element pressing unit 190, the cartridge pressing unit 191 also descends in the direction of arrow Z2 in conjunction with the operation of closing the front door 11 and serves to press the process cartridge 100 against the aforementioned positioning portion 171VL. Further, although details will be described later, the cartridge pressing mechanisms (190, 191) also simultaneously serve to push down the moving members 152L, 152R (the moving member 152L is not shown) of the process cartridge 100 described later.

[0041] [Drive transmission mechanism] Using FIGS. 8 and 9, the drive transmission mechanism of the main body in this embodiment will be described. FIG. 8(a) is a perspective view omitting the illustration of the process cartridge 100 and the tray 171 in the state of FIG. 3 or FIG. 4. FIG. 8(b) is a perspective view omitting the illustration of the process cartridge 100, the front door 11, and the tray 171 in the state of FIG. 1. FIG. 9 is a side view of the process cartridge 100 seen from the drive side, showing a state in which the moving member 152R of the process cartridge 100 is pushed down by a cartridge pressing mechanism (not shown) and engaged so as to overlap with a separation control member 196R described later.

[0042] As shown in FIG. 9, the process cartridge in this embodiment has a developing coupling portion (rotation driving force receiving portion) 132a and a drum coupling member (photosensitive member coupling member) 143. When the front door 11 is closed (the state shown in FIG. 8(b)), a main body side drum driving coupling 180 and a main body side developing driving coupling 185 that transmit driving force to the process cartridge 100 are configured to project in the direction of arrow Y1 by a link mechanism (not shown). Also, when the front door 11 is opened (the state shown in FIG. 8(a)), the drum driving coupling 180 and the developing driving coupling 185 are configured to retract in the direction of arrow Y2. By retracting each coupling from the insertion and removal locus (in the X1 direction and X2 direction) of the process cartridge, the insertion and removal of the aforementioned tray 171 are not inhibited.

[0043] When the front door 11 is closed and the driving of the apparatus main body 170 is started, the aforementioned drum driving coupling 180 engages with the drum coupling member 143. Further, the main body side developing driving coupling 185 engages with the developing coupling portion 132a, and driving force is transmitted to the process cartridge 100. Note that the transmission of driving force to the process cartridge 100 is not limited to two locations as described above, and a mechanism may be provided in which driving force is input only to the drum coupling and transmitted from there to the developing roller.

[0044] [Intermediate transfer unit configuration] The intermediate transfer unit 12 of the image forming apparatus main body in this embodiment will be described with reference to FIG. 8. In this embodiment, when the front door 11 is closed, the intermediate transfer unit 12 is raised in the direction of arrow R2 by a link mechanism (not shown) and moves to the position during image formation (the position where the photosensitive drum 104 and transfer contact the transfer belt 12a). Also, when the front door 11 is opened, the intermediate transfer unit 12 descends in the direction of arrow R1, and the photosensitive drum 104 and transfer and the transfer belt 12a are separated. That is, in a state where the process cartridge 100 is set in the tray 171, the photosensitive drum 104 and transfer and the transfer belt 12a are separated and abutted according to the opening and closing operation of the front door 11.

[0045] Incidentally, the contact and separation operation draws a rotation locus centered on the center point PV1 shown in FIG. 3, and the intermediate transfer unit 12 moves up and down. Also transfer The transfer belt 12a is driven by receiving force from a gear (not shown) arranged coaxially with PV1. Therefore, by using the aforementioned position PV1 as the rotation center, the intermediate transfer unit 12 can be moved up and down without moving the center of the gear. As a result, there is no need to move the center of the gear, and the position of the gear can be maintained with high precision.

[0046] With the above configuration, when the process cartridge 100 is set in the tray 171, when the tray 1 7 1 is inserted and removed, the photosensitive drum 104 and transfer The transfer belt 12a does not slide, preventing damage to the photosensitive drum 104 and image degradation due to the charging memory.

[0047] [Developing Separation Control Unit] With reference to FIGS. 7, 10, and 11, the separation mechanism of the image forming apparatus main body in this embodiment will be described. FIG. 10 is a cross-sectional view of the image forming apparatus M cut along the driving side end face of the process cartridge 100. FIG. 11 is a perspective view of the developing separation control unit as viewed obliquely from above. In this embodiment, the developing separation control unit 195 controls the separation and contact operation of the developing unit 109 with respect to the photosensitive drum 104 by engaging with a part of the developing unit 109. As shown in FIG. 7, the developing separation control unit 195 is located below the apparatus main body 170. Specifically, the developing separation control unit 195 is arranged vertically below (in the direction of arrow Z2) the developing coupling portion 132a and the drum coupling member 143. Also, the developing separation control unit 195 is an intermediate transfer unitIt is disposed on both sides of the photosensitive drum 104 in the longitudinal direction (Y1, Y2 directions) of 12. That is, the developing separation control unit 195 arranges the developing separation control unit 195R on the driving side and the developing separation control unit 195L on the non-driving side.

[0048] The developing separation control unit 195R has four separation control members (force applying members) 196R corresponding to the process cartridges 100 (100Y, 100M, 100C, 100K). The four separation control members have substantially the same shape. The fixed plate 195Ra is always fixed to the main body of the image forming apparatus. The separation control member 196R is configured to be movable in the W41 and W42 directions by a control mechanism (not shown). The W41 and W42 directions are substantially parallel to the arrangement direction of the process cartridges 100 mounted on the apparatus main body 170. Similar to the developing separation control unit 195R, the developing separation control unit 195L has four separation control members (force applying members) 196L corresponding to the process cartridges 100 (100Y, 100M, 100C, 100K). The four separation control members have substantially the same shape. The fixed plate 195La is always fixed to the main body of the image forming apparatus. The separation control member 196L is configured to be movable in the W41 and W42 directions by a control mechanism (not shown).

[0049] Also, in order to control the separation and contact operation of the developing unit 109, the developing separation control unit 195 needs to engage with a part of the developing unit 109. Therefore, separation a part of the developing separation control unit 195 and a part of the developing unit 109 need to overlap in the vertical direction (Z1, Z2 directions) (see FIG. 9). Therefore, after the process cartridge 100 is inserted in the X1 direction, in order to overlap in the vertical direction (Z1, Z2 directions) as described above, a part of the developing unit 109 (in this embodiment, the moving member 152 L, 152RIt is necessary to project it in the Z2 direction. In addition, when the entire developing separation control unit 195 is lifted in the same manner as the above-described intermediate transfer unit 12 in order to engage them, there are problems such as an increase in the operating force of the interlocking front door 11 and a complication of the drive train. In this embodiment, the developing separation control unit 195 is fixed to the apparatus main body 170, and a part of the developing unit 109 (the moving member 152 L, 152R ) is projected downward (Z2) in the apparatus main body 170. One of the reasons for adopting this method is to address this problem. Also, the mechanism for projecting the moving member 152 L, 152R utilizes the mechanisms of the above-described memory element pressing unit 190 and cartridge pressing unit 191 as they are, so there are no problems as described above and an increase in the cost of the apparatus main body can be suppressed.

[0050] Note that the entire developing separation control unit 195 is fixed to the apparatus main body 170. On the other hand, a part of the developing separation control unit 195 is configured to be movable in order to engage with the moving member 152 L, 152R and impart an operation so that the developing unit 109 is in a separated state (separated position, retracted position) and a contacting state (contacting position) with respect to the photosensitive drum 104.

[0051] As described above, the developing separation control unit, although detailed description is omitted, is configured to contact and separate the developing roller 106 and the photosensitive drum 104 by acting on the moving member 152 L, 152R of the developing unit 109.

[0052] [Overall Configuration of the Process Cartridge] The configuration of the process cartridge will be described with reference to FIGS. 12 and 13. FIG. 12 is an exploded perspective view of the process cartridge 100 as viewed from the drive side, which is one end side in the axial direction of the photosensitive drum 104. FIG. 13 is a perspective view of the process cartridge 100 as viewed from the drive side.

[0053] In this embodiment, the first to fourth process cartridges 100 (100Y, 100M, 100C, 100K) may differ in the color of the toner they contain, the toner filling amount, or the control by the apparatus main body 170. However, although there may be differences in dimensions and the like among these four process cartridges, their basic structures and functions are the same. Therefore, hereinafter, one process cartridge 100 will be described as a representative.

[0054] Each process cartridge 100 includes a photosensitive drum (photoconductor) 104 and process means that act on the photosensitive drum 104. Here, as the process means, there are a charging roller 105 as a charging means (charging member) for charging the photosensitive drum 104, a developing roller 106 as a developing means (developing member) for attaching toner to the photosensitive drum 104 and developing the latent image formed on the photosensitive drum 104, and the like. The developing roller 106 carries toner on its surface. Note that the process cartridge 100 may further include, as additional process means, a cleaning blade or brush that contacts the photosensitive drum 104 as a cleaning means (cleaning member) for removing residual toner on the surface of the photosensitive drum 104. Further, as additional process means, the process cartridge 100 may include a light guide member such as a light guide or lens for irradiating light to the photosensitive drum 104 and a light source as a charge removal means for discharging the surface of the photosensitive drum 104. And the process cartridge 100 is divided into a drum unit (first unit) 108 (108Y, 108M, 108C, 108K) and a developing unit (second unit) 109 (109Y, 109M, 109C, 109K).

[0055] [Configuration of Drum Unit] As shown in FIGS. 2 and 12, the drum unit 108 has a photosensitive drum 104, a charging roller 105, and a first drum frame body portion 115. Further, the drum unit 108 includes a drive-side cartridge cover member 116 as a second drum frame body portion attached and fixed to the first drum frame body portion 115 and non- driveIt has a moving-side cartridge cover member 117. The photosensitive drum 104 is arranged at both ends in the longitudinal direction of the process cartridge 100 with drive-side cartridge cover members 116, non- drive The moving-side cartridge cover member 117 rotatably supports the photosensitive drum 104 about the rotation axis (rotation center) M1. These first drum frame body parts 115, the drive-side cartridge cover member 116 as the second drum frame body part, and non- drive The moving-side cartridge cover member 117 constitutes a drum frame body (first frame body or photosensitive member frame body) that rotatably supports the photosensitive drum 104. The drive-side cartridge cover member 116 and non- drive The moving-side cartridge cover member 117 will be described later.

[0056] As shown in FIGS. 12 and 13, at one end side in the longitudinal direction of the photosensitive drum 104, there is provided a drum coupling member 143 for transmitting a driving force to the photosensitive drum 104. As described above, drum the coupling member 143 engages with a main body-side drum drive coupling 180 (see FIG. 8) as a drum drive output part of the apparatus main body 170. Then, the driving force of a drive motor (not shown) of the apparatus main body 170 is transmitted to the photosensitive drum 104 and it rotates in the direction of arrow A (see FIG. 2). Further, the photosensitive drum 104 has a drum flange 142 at the other end side in the longitudinal direction. The charging roller 105 is first supported by the drum frame body part 115 so as to be in contact with the photosensitive drum 104 and be capable of driven rotation. Note that the rotation axis M1 is parallel to the longitudinal direction of the process cartridge 100 and the longitudinal direction of the drum unit 108.

[0057] [Configuration of Developing Unit] As shown in FIG. 2, the developing unit 109 includes a developing roller 106, a toner conveyance roller (developer supply member) 107, a developing blade 130, a developing container 120, and the like. The developing container 120 that constitutes the frame of the developing unit is composed of a developing frame 121 and a lid member 122. The developing frame 121 and the lid member 122 are joined by ultrasonic welding or the like. The developing container 120 has a toner storage portion (toner storage chamber) 129 that stores toner to be supplied to the developing roller 106, and a developing space 123 as a space for supplying toner to the developing roller 106 in which the toner conveyance roller 107 is disposed. At both longitudinal ends of the developing container 120, a driving-side bearing 126 and a non-driving-side bearing 127 are respectively attached and fixed. Then, the developing container 120 rotatably supports the developing roller 106, the toner conveyance roller 107, and a stirring member 129a (see FIG. 2) via the driving-side bearing 126 and the non-driving-side bearing 127, and holds the developing blade 130. In this way, the developing container 120, the driving-side bearing 126, and the non-driving-side bearing 127 constitute a developing frame (second frame) that rotatably supports the developing roller 106 about a rotation axis (rotation center) M2.

[0058] The stirring member 129a stirs the toner in the toner storage portion 129 by rotating. The toner conveyance roller (developer supply member) 107 contacts the developing roller 106, supplies toner to the surface of the developing roller 106, and also strips off toner from the surface of the developing roller 106. The developing blade 130 is formed by attaching an elastic member 130b, which is a sheet-like metal having a thickness of about 0.1 mm, to a support member 130a, which is a metal material having an L-shaped cross section, by welding or the like. The developing blade 130 regulates the layer thickness (thickness of the toner layer) of the toner on the circumferential surface of the developing roller 106 as a regulating member, and forms a toner layer having a predetermined thickness between the elastic member 130b and the developing roller 106. The developing blade 130 is attached to the developing container 120 with fixing screws 118 at two locations on one end side and the other end side in the longitudinal direction. The developing roller 106 is composed of a core metal 106c made of a metal material and a rubber portion 106d.

[0059] As shown in FIGS. 12 and 14, a developing coupling portion 132a for transmitting a driving force to the developing unit 109 is provided at one end side in the longitudinal direction of the developing unit 109. The developing coupling portion 132a engages with a main body side developing drive coupling 185 (see FIG. 8) as a developing drive output portion of the apparatus main body 170, and is a member that rotates by receiving the rotational driving force of a drive motor (not shown) of the apparatus main body 170. The driving force received by the developing coupling portion 132a is transmitted by a drive train (not shown) provided in the developing unit 109, whereby the developing roller 106 can be rotated in the direction of arrow D in FIG. 2. A developing cover member 128 for supporting and covering the developing coupling portion 132a and the drive train (not shown) is provided at one end side in the longitudinal direction of the developing unit 109. Incidentally, the outer diameter of the developing roller 106 is set smaller than the outer diameter of the photosensitive drum 104. The outer diameter of the photosensitive drum 104 in this embodiment is set in the range of Φ18 to Φ22, and the outer diameter of the developing roller 106 is set in the range of Φ8 to Φ14. By setting the outer diameter in this way, an efficient arrangement becomes possible. However, the outer diameters of the photosensitive drum 104 and the developing roller 106 are not limited to the above ranges. The rotation axis M2 is in the longitudinal direction of the process cartridge 100 and the longitudinal direction of the developing unit 109 and is parallel.

[0060] [Assembly of Drum Unit and Developing Unit] The assembly of the drum unit 108 and the developing unit 109 will be described with reference to FIG. 12. The drum unit 108 and the developing unit 109 are provided at both ends in the longitudinal direction of the process cartridge 100 with a drive side cartridge cover member 116 and a non- driveIt is coupled by the driving-side cartridge cover member 117. The driving-side cartridge cover member 116 is provided at one end side in the longitudinal direction of the process cartridge 100. The driving-side cartridge cover member 116 is provided with a developing unit support hole 116a for supporting the developing unit 109 so as to be swingable (movable). The non-driving-side cartridge cover member 117 is provided at the other end side in the longitudinal direction of the process cartridge 100. The non-driving-side cartridge cover member 117 is provided with a developing unit support hole 117a for supporting the developing unit 109 so as to be swingable. Further, the driving-side cartridge cover member 116 and the non- drive The non-driving-side cartridge cover member 117 is provided with drum support holes 116b and 117b for rotatably supporting the photosensitive drum 104.

[0061] Here, at one end side in the longitudinal direction of the process cartridge 100, the outer diameter portion of the cylindrical portion 128b of the developing cover member 128 is fitted into the developing unit support hole 116a of the driving-side cartridge cover member 116. At the other end side in the longitudinal direction of the process cartridge 100, the non- drive The outer diameter portion of the cylindrical portion (not shown) of the non-driving-side bearing 127 is fitted into the developing unit support hole 117a of the non-driving-side cartridge cover member 117. Further, both ends in the longitudinal direction of the photosensitive drum 104 are fitted into the drum support hole 116b of the driving-side cartridge cover member 116 and the non- drive driving-side cartridge cover member 117 into the drum support hole 117b. And the driving-side cartridge cover member 116 and the non- drive driving-side cartridge cover member 117 are fixed to the drum unit 108 by screws 301. Note that the fixing method may be an adhesive or the like instead of screws. Thereby, the developing unit 109 is supported by the driving-side cartridge cover member 116 and the non- drive driving-side cartridge cover member 117 so as to be movable with respect to the drum unit 108 (photosensitive drum 104). In such a configuration, the developing roller 106 can be positioned at a position where it acts on the photosensitive drum 104 during image formation.

[0062] Fig. 13 shows a state in which the drum unit 108 and the developing unit 109 are assembled by the above steps and integrated as the process cartridge 100. Note that the center of the developing unit support hole 116a of the driving-side cartridge cover member 116 and the non- drive axis connecting the center of the developing unit support hole 117a of the non-driving-side cartridge cover member 117 is referred to as the swing axis (rotation axis, center of rotation) K (see Figs. 12 and 13). Here, the cylindrical portion 128b of the developing cover member 128 on one end side in the longitudinal direction of the process cartridge 100 is coaxial with the developing coupling portion 132a. That is, the rotation axis of the developing coupling portion 132a is coaxial with the swing axis K. Further, the developing unit 109 is rotatably supported about the swing axis K. In a state where the drum unit 108 and the developing unit 109 are assembled and integrated as the process cartridge 100, the rotation axis M1, the rotation axis M2, and the swing axis K are substantially parallel to each other. Also, in this state, the rotation axis M1, the rotation axis M2, and the swing axis K are each substantially parallel to the longitudinal direction of the process cartridge 100.

[0063] [Toner Sealing Structure of Developing Unit] The toner sealing structure of the developing unit 109 will be described with reference to Figs. 14 to 17. Fig. 14 is an exploded perspective view seen from the driving side when the developing blade 130 and the blade lower seal 160 are assembled to the developing container 120. Fig. 15 is a view of the assembled developing unit 109 seen from the assembling direction of the developing blade 130. Fig. 16 is a schematic cross-sectional view schematically showing the cross-sectional structure of the blade lower seal 160 when the blade lower seal 160 is viewed from the longitudinal direction of the process cartridge 100. Fig. 17 is a schematic cross-sectional view schematically showing the cross-sectional structure of the end seal 200 when the end seal 200 is viewed from the substantially X3 direction in Fig. 14. direction.

[0064] The developing container 120 (developing frame 121) has a substantially rectangular opening that communicates the developing space 123 with the outside, and the developing roller 106 is disposed at this opening. Along the substantially rectangular edge of this opening, as shown in FIG. 15, the developing blade 130 (blade lower seal 160), the end seal 200, and the sheet member 210 are provided in a continuous arrangement so as to annularly surround the opening. By these plurality of members, among the outer peripheral surface of the developing roller 106, the region exposed (facing) to the developing space 123 of the developing container 120 and the region exposed to the outside of the developing container 120 are respectively defined. That is, as shown in FIG. 15, the opening region surrounded by the developing blade 130, the end seal 200, and the sheet member 210 becomes the region exposed to the developing space 123 on the outer peripheral surface of the developing roller 106. Surrounding this region, the developing blade 130 (elastic member 130b), the end seal 200, and the sheet member 210 are in close contact with the outer peripheral surface of the developing roller 106.

[0065] As shown in FIG. 15, the developing blade 130 and the sheet member 210 are respectively disposed on the two long sides parallel to the longitudinal direction of the developing container 120 among the four sides constituting the rectangular edge of the opening of the developing container 120. Among these two long sides, the developing blade 130 is disposed on the side downstream in the rotation direction of the developing roller 106, and the sheet member 210 is disposed on the side upstream. The developing blade 130 has a support member 130a as a support portion and an elastic member 130b as a sliding portion. The support member 130a is disposed so as to extend in the longitudinal direction of the developing container 120, and both ends thereof are fixed to the developing frame 121 by screws 118. A blade lower seal 160 is interposed between the region between both ends fixed by the screws 118 of the support member 130a and the developing frame 121, and between the support member 130a and the developing frame bodyThe gap between it and 121 is sealed. That is, the blade-under seal 160 is disposed along the longitudinal direction of the developing container 120 along the side of the opening of the developing container 120 in the longitudinal direction as a longitudinal seal member (first seal member). The elastic member 130b is disposed such that the downstream end in the rotation direction of the developing roller 106 is fixed to the support member 130a, and the upstream end is in sliding contact with the circumferential surface of the developing roller 106 along the longitudinal direction.

[0066] Also, end seals 200 are respectively disposed in a symmetric arrangement configuration in the longitudinal direction on the two short sides parallel to the rotation direction of the remaining developing roller 106 among the four sides constituting the rectangular edge of the opening of the developing container 120. The end seal 200 is attached to an end-seal attachment surface 121h (third attachment surface) provided on the two short sides (see FIG. 20). The pair of end seals 200 provided are provided so as to extend along the rotation direction of the developing roller 106 so as to connect the longitudinal end portions of the developing blade 130 and the sheet member 210 respectively. The end seal 200 as an end-seal member (second seal member) is in sliding contact with both end portions in the longitudinal direction of the developing container 120 (the rotation axis direction of the developing roller 106) of the outer peripheral surface of the developing roller 106.

[0067] As shown in FIG. 16, the blade-under seal 160 is composed of a double-sided tape 160a and an elastic foam member 160b, and is attached to a blade-under seal attachment surface 121a as the first attachment surface of the developing frame 121 by the double-sided tape 160a. Then, when the developing blade 130 described later is assembled to the developing frame 121, it is configured to fill the gap between the support member 130a and the developing frame 121.

[0068] The developing blade 130 is composed of a support member 130a and an elastic member 130b. The elastic member 130b is made of a thin plate of stainless steel or phosphor bronze with a thickness of about 0.1 mm. Also, the support member 130a is made of a steel plate with a thickness of 1 to 2 mm. The support member 130a and the elastic member 130b are positioned by a positioning mechanism (not shown) and joined by spot welding with a laser or the like. Further, the support member 130a is provided with a first notch portion 131 for positioning in the developing frame 121, and by fitting with the support member positioning portion 1210 of the developing frame 121, the position in the longitudinal direction of the process cartridge 100 is determined. Also, at both longitudinal ends of the support member 130a, second notch portions 132 are provided, which are used as injection ports when injecting the hot melt resin HM described later. Furthermore, the support member 130a is fixed by screws 118 in a state where it abuts against the blade mounting surfaces 121b (121bR, 121bL) as the second mounting surfaces of the developing frame 121. Note that, among the short side direction of the elastic member 130b, the side opposite to the side joined to the support member 130a is a free end, and by a part of this free end coming into contact with the circumferential surface of the developing roller 106, the amount of toner held by the developing roller 106 is regulated. Moreover, a first notch portion 131 for positioning in the developing frame 121 is provided, and by fitting with the support member positioning portion 1210 of the developing frame 121, the position in the longitudinal direction of the process cartridge 100 is determined. Also, at both longitudinal ends of the support member 130a, second notch portions 132 are provided, which are used as injection ports when injecting the hot melt resin HM described later. Furthermore, the support member 130a is fixed by screws 118 in a state where it abuts against the blade mounting surfaces 121b (121bR, 121bL) as the second mounting surfaces of the developing frame 121. Note that, among the short side direction of the elastic member 130b, the side opposite to the side joined to the support member 130a is a free end, and by a part of this free end coming into contact with the circumferential surface of the developing roller 106, the amount of toner held by the developing roller 106 is regulated.

[0069] As shown in FIG. 14, in this embodiment, an end seal 200 and a sheet member 210 are arranged on the developing frame 121.

[0070] As shown in FIG. 17, the end seal 200 has a fiber layer 200d made of resin fibers such as ethylene fluoride and an elastic foam layer 200b, which are attached by an adhesive layer 200c. Further, an adhesive layer 200a such as a double-sided tape for attaching to the developing frame 121 is disposed under the elastic foam layer 200b. The end seal 200 is disposed at both longitudinal ends of the developing roller 106 and is curved so that the fiber layer 200d contacts the circumferential surface of the developing roller 106. The end seal 200 has an end face 201, a first notch 202, and a second notch 203 at the end on the side where the blade mounting surface 121b is disposed. The end face 201 is a surface that constitutes a space Q into which a hot melt resin HM described later is injected. The first notch 202 and the second notch 203 are provided so as not to extremely narrow the regions of communication portions S1 and S2 described later.

[0071] The sheet member 210 is a flexible resin sheet made of a resin such as PPS and having a thickness of about 0.1 mm, and is attached to the developing frame 121 by a double-sided tape or the like (not shown). The sheet member 210 is disposed on the downstream side in the rotation direction of the developing roller 106 with respect to the developing blade 130 and over the entire longitudinal direction of the developing frame 121. The side of the sheet member 210 where the tip in the short direction faces the developing roller 106 is a free end, and a part of this free end is configured to contact the circumferential surface over the entire longitudinal direction of the developing roller 106. Further, the longitudinal direction of the sheet member 210 is configured to contact and overlap with the fiber layer 200d of the end seal 200 described above. The end seal 200 and the sheet member 210 are configured to ensure their adhesion by injecting a filler such as a hot melt resin into a contact portion (not shown).

[0072] Next, with reference to FIGS. 18 to 23, the seal configuration between the developing blade 130, the blade lower seal 160, and the end seal 200 will be described in detail. Note that for the seal configuration in this embodiment, there is no difference in configuration between the drive side and the non-drive side except that they are symmetric in shape. Therefore, in the following description, the drive side will be used for explanation, but the same applies to the non-drive side. FIG. 18 is a perspective view (a) seen from the non-drive side and a perspective view (b) seen from the drive side, omitting the developing blade 130 and the screw 118 for the sake of explanation, from the state where the developing blade 130 is assembled (the state in FIG. 15). FIG. 19 is a view of the state of FIG. 18 seen from the normal direction of the blade mounting surface 121bR of the developing frame body 121. FIG. 20 is a cross-section taken along HD-HD in FIGS. 15 and 19, and is a schematic cross-sectional view showing the nozzle portion 300 of the injection device when injecting a filler such as hot melt resin. FIG. 21 is a schematic cross-sectional view showing the process of injecting the hot melt resin HM in the order of (a) to (d) in the same cross-section as FIG. 20. FIG. 22 is a schematic cross-sectional view after injecting the hot melt resin HM in the same cross-section as FIG. 20. FIG. 23 is a view (omitting the developing blade 130 and the screw 118) seen from the same direction as FIG. 19 (the normal direction of the blade mounting surface 121bR of the developing frame body 121) after injecting the hot melt resin HM. The hot melt resin HM in this embodiment is composed of a mixture of a thermoplastic rubber, a tackifying resin, etc., and has the characteristic of liquefying by heating and curing to a solid having elasticity by cooling. As shown in FIG. 23, by curing the hot melt resin HM, a sealing member FHM that fills the space Q described later is formed, and toner leakage from the developing space 123 to the outside of the developing container 120 is suppressed.

[0073] As shown in Fig. 19, in this embodiment, a space Q is provided between the under-blade seal 160, the end seal 200, and the developing frame 121, and it has a communication portion S1 that communicates with the developing space 123. This indicates that there is no need for an assembly (refer to Patent Document 1) in which the under-blade seal 160 and the end seal 200 are attached while ensuring a contact pressure, and the assembly cost can be reduced. However, since the under-blade seal 160 and the end seal 200 are not in close contact, in this state, the toner present in the developing space 123 will leak out to the outside of the developing container 120 through the communication portion S1. Furthermore, a gap is also provided between the third wall portion 121g that is connected in a direction substantially perpendicular to the blade mounting surface 121b and the end seal 200, and it has a communication portion S2 that communicates with the outside of the developing container 120. As a method for preventing the toner from leaking out, it is preferable to fill the communication portion S1, but toner sealing can also be achieved by filling both the space Q and the communication portion S2. In this embodiment, a hot melt resin HM is injected as a configuration for sealing the toner leakage from the communication portions S1 and S2, and this will be described in detail later.

[0074] As shown in Figs. 18 and 19, the developing frame 121 has a space Q as an injection region for the hot melt resin HM. The space Q is a space surrounded by the first wall portion 121e, the second wall portion 121f, the third wall portion 121g, the first inclined surface 121c, the second inclined surface 121d, the first end surface 160c of the under-blade seal 160, and the end surface 201 of the end seal 200.

[0075] This space Q is in the developing frame 121, for the developing blade 1 30、The mounting portions (each mounting surface) of the blade lower seal 160 and the end seal 200 are formed by being arranged as follows. That is, in the axial direction of the rotation axis of the developing roller 106, the blade lower seal mounting surface 121a and the blade mounting surface 121b are separated (spaced apart). Also, in the rotation direction of the developing roller 106, the end seal mounting surface 121h is provided at a position separated upstream in the rotation direction from the blade lower seal mounting surface 121a and the blade mounting surface 121b. The region between the blade lower seal mounting surface 121a, the blade mounting surface 121b, and the end seal mounting surface 121h in the developing frame 121 is a concave portion 121q recessed with respect to each of the blade lower seal mounting surface 121a, the blade mounting surface 121b, and the end seal mounting surface 121h. For the end seal 200, the end of the end seal 200 on the downstream side in the rotation direction of the developing roller 106 sandwiches the longitudinal end of the elastic member 130b between it and the developing roller 106. The blade lower seal 160 is provided between the support member 130a and the blade lower seal mounting surface 121a so as to be separated from each of the blade mounting surface 121b, the end seal mounting surface 121h, and the end seal 200. The end seal 200 is attached to the end seal mounting surface 121h so as to be separated from each of the support member 130a, the blade lower seal 160, the blade lower seal mounting surface 121a, and the blade mounting surface 121b. The above arrangement configuration takes into account manufacturing errors of each member, assembly errors to the developing frame 121, and the assemblability of each member. With the above arrangement configuration, a space surrounded by the developing frame 121 (concave portion 121q), the developing blade 130, the blade lower seal 160, and the end seal 200 is formed, which is a space that communicates the developing space 123 of the developing frame 121 with the outside of the developing frame 121.

[0076] The concave portion 121q, which is the wall surface of the frame body 121 forming the above-mentioned communication space, has a first wall portion 121e, a second wall portion 121f, a first inclined surface 121c, and a second inclined surface 121d. The first wall portion 121e is a surface that extends in a direction substantially perpendicular to the blade mounting surface 121b and is arranged facing the non-driving side. The second wall portion 121f is arranged opposite to the first wall portion 121e and is configured as a surface connected to the blade lower seal mounting surface 121a. Further, between the first wall portion 121e and the second wall portion 121f, there are arranged a first inclined surface 121c inclined with respect to the blade mounting surface 121b and a second inclined surface 121d continuous with the first inclined surface 121c and inclined with respect to the blade mounting surface 121b. The first and second inclined surfaces 121c and 121d are formed in a region of the concave portion 121q that extends from between the blade lower seal mounting surface 121a and the blade mounting surface 121b to the end seal mounting surface 121h. The first and second inclined surfaces 121c and 121d are inclined with respect to the blade mounting surface 121b. Note that FIG. 20 shows a reference plane RS including the blade mounting surface 121b, which is a reference for the degree of inclination of the first and second inclined surfaces 121c and 121d. The first and second inclined surfaces 121c and 121d are surfaces inclined so as to narrow the space Q in the direction in which the developing roller 106 is arranged (substantially the Z4 direction in FIG. 19) with respect to the blade mounting surface 121b. That is, when viewed in a direction orthogonal to the normal direction of the blade mounting surface 121b as shown in FIG. 20, the first and second inclined surfaces 121c and 121d are inclined such that the distance between the longitudinal seal blade lower seal as a member 160 and the longitudinal seal becomes shorter as it approaches the end seal mounting surface 121h. The first and second inclined surfaces 121c and 121d are configured to connect to the communication portion S1 and the communication portion S2 at the ends in the direction in which the developing roller 106 is arranged. That is, the first and second inclined surfaces 121c and 12 1d extend to a region close to the developing space 123 between the blade lower seal mounting surface 121a and the end seal mounting surface 121h and are connected to the communication portion S1. Further, the first and second inclined surfaces 121c and 121d extend to a region close to the outside of the developing frame body 121 between the blade mounting surface 121b and the end seal mounting surface 121h and are connected to the communication portion S2.

[0077] As shown in FIG. 23, the hot melt resin HM is filled in the space Q so that a first sealing portion HM1 that closes the first communication portion S1 and a second sealing portion HM2 that closes the second communication portion S2 are formed, and then becomes a sealing member FHM by curing.

[0078] In this embodiment, a first inclined surface 121c and a second inclined surface 121d are provided as surfaces inclined with respect to the blade mounting surface 121b. That is, as the inclined surface, a configuration is adopted in which the angle with respect to the blade mounting surface 121b changes stepwise toward the end seal mounting surface 121h. However, depending on the arrangement configuration of the end seal 200 described later, the second inclined surface 121d is not necessarily required. Therefore, for example, the first inclined surface 121c may be configured to be connected to the end seal mounting surface 121h.

[0079] Note that the angle θ1 between the first inclined surface 121c and the blade mounting surface 121b and the angle θ2 between the second inclined surface 121d and the blade mounting surface 121b are configured to satisfy the following formulas (1) and (2) (see FIG. 20). 0 < θ1 < 90 …(1) 0 < θ2 < 90 …(2)

[0080] [Assembly process (manufacturing method) of developing unit] With reference to FIGS. 20 and 21, the filling of the hot melt resin in this embodiment will be described in detail. With various seal members (blade lower seal 160, end seal 200) and the developing blade 130 attached to the developing frame 121, the hot melt resin HM is injected from the nozzle portion 300 of an injection device (not shown).

[0081] That is, the assembly process of the developing unit 109 of the present embodiment generally includes a first attachment process of attaching various seal members and the developing blade 130 to the developing frame 121, an injection process of injecting the hot melt resin HM, and a second attachment process of attaching the remaining members. In the first attachment process, the blade lower seal 160, the end seal 200, the sheet member 210, and the developing blade 130 are attached to the developing frame 121. After the first attachment process, in the injection process, the hot melt resin HM is injected into the space Q. After the injected hot melt resin HM hardens and a sealing member FHM (see FIG. 23) is formed in a predetermined gap, the remaining members such as the developing roller 106 are attached to the developing frame 121. Thereby, various members are integrated, and the developing unit 10 9 is completed.

[0082] In the injection process, the hot melt resin HM ejected from the nozzle portion 300 is injected and filled into the space Q through the second notch portions 132 provided at both longitudinal ends of the support member 130a. The second notch portions 132 are provided so as to overlap at least a part of the first and second inclined surfaces 121c and 121d when viewed in the extending direction of the blade attachment surface 121b. That is, the second notch portions 132 are provided in a shape in which at least a part of the first and second inclined surfaces 121c and 121d is cut out so as to be visible (exposed to the outside) from the outside through the second notch portions 132. The region where the second notch portions 132 are provided in the support member 130a is an area open to the outside in the developing unit 109, as shown in FIG. 14 and the like, and has an arrangement configuration that allows easy access to the nozzle portion 300 of the injection device. In addition, by adopting a simple configuration in which a notch-shaped portion is provided in the support member 130a as an injection port for the hot melt resin HM, an injection structure for the hot melt resin HM can be realized at low cost. Note that the configuration of the injection port is not limited to the configuration with the above-described notch portions.

[0083] In this embodiment, due to constraints such as the attachment of the developing frame 121 to the injection device, the X4 direction in FIG. 20 is preferably shown as the gravitational direction. However, depending on the attachment to the injection device, the viscosity of the hot melt resin HM, and the set angles of θ1 and θ2, it is desirable to appropriately adjust to the Z4 direction or the like.

[0084] When the hot melt resin HM is filled into the space Q (see FIG. 19), it is heated to a predetermined temperature and liquefied and a predetermined pressure is applied, so that it is injected along the substantially injection locus HT and reaches the landing point P (the state in FIG. 21(a)). Note that the position and angle of the nozzle portion 300, the injection pressure of the hot melt resin HM, etc. are adjusted so that the landing point P is located on the first inclined surface 121c. The hot melt resin HM that has reached the landing point P flows along the first inclined surface 121c by the thrust in the Z4 direction in the figure due to the injection pressure and flows toward the second inclined surface 121d (the state in FIG. 21(b)). In this process, the hot melt resin HM also contacts the first end surface 160c of the blade lower seal 160, the first wall portion 121e, and the second wall portion 121f.

[0085] Here, the first end surface 201 of the end seal 200 is arranged to overlap with the second inclined surface 121d in the Z3 direction so as to form the wedge portion 204. That is, the end of the end seal 200 on the downstream side in the rotation direction of the developing roller 106 protrudes to the downstream side of the region where the end of the end seal 200 contacts the end seal mounting surface 121h. As a result, the inclined surfaces 121c and 121d form a wedge portion 204, which is a gap that becomes narrower as it approaches the end seal mounting surface 121h in the region close to the end seal mounting surface 121h.

[0086] The hot melt resin HM that has flowed onto the second inclined surface 121d flows while filling the wedge portion 204 by the thrust force in the aforementioned Z4 direction and coming into contact with the first end surface 201 and the support member 130a of the developing blade 130 (the state in Fig. 21(c)). Further, when the hot melt resin HM is injected, since the flow direction is guided by the first inclined surface 121c and the second inclined surface 121d, it flows into the communication portion S1 and the communication portion S2 (the state in Fig. 21(d)). In this process, the hot melt resin HM also comes into contact with the elastic member 130b of the developing blade 130, and the space Q and the communication portions S1 and S2 are filled without gaps by the hot melt resin HM. When the injection of the hot melt resin HM is completed, the hot melt resin HM hardens by cooling and is fixed in a state having elasticity and adhesiveness (the states in Figs. 22 and 23). Note that, as the order in which the injected hot melt resin HM comes into contact, it is preferable to arrange the developing blade 130 made of a metal with a small specific heat so that it comes last. By doing so, the hot melt resin HM can be surely poured into the communication portions S1 and S2 without being cooled and hardened before reaching the desired region. possible.

[0087] According to this embodiment, it is not necessary to assemble the blade bottom seal 160 and the end seal 200 with high precision, and the sealing property can be stably ensured by filling a small amount of sealing member into the communication portion which is the joint portion between the seal members. Therefore, it is possible to realize a reduction in the manufacturing cost of the developing unit.

[0088] (Embodiment 2) With reference to Fig. 24, the arrangement configuration of the end seal 200 will be supplementarily described. Fig. 24 is a cross-sectional view seen from the same direction as Fig. 20 of a configuration (Embodiment 2) in which only one inclined surface 1212c is arranged without arranging the second inclined surface 121d. Here, only the points different from Embodiment 1 in Embodiment 2 will be described. The configuration of Embodiment 2 not particularly described here is the same as that of Embodiment 1, and the repeated description will be omitted.

[0089] The inclined surface 1212c is a surface connected to the communication portions S1 and S2, similar to the aforementioned first inclined surface 121c and second inclined surface 121d, and is configured to be connected to the end seal mounting surface 1212h. Here, the end surface 201 of the end seal 200 is arranged to overlap with the inclined surface 1212c in the Z3 direction so as to form the wedge portion 2042. Thereby, the injected hot melt resin can flow into the wedge portion 2042, ensuring the adhesion with the end seal 200.

[0090] (Others) As described above, by inclining the surface where the hot melt resin HM lands with respect to the injection direction, the thrust force due to the injection pressure can be directed along the inclined surface, so that it can flow actively toward the desired regions (communication portions S1 and S2 in this embodiment). As a method of inclining the surface where it lands in order to make it flow to the desired region, for example, in the configuration shown in FIG. 20, the first inclined surface 121c is arranged perpendicular to the blade mounting surface 121bR, and the nozzle portion 300 of the injection device is arranged at a position rotated clockwise around the landing point P, which can also be realized. However, in this case, since it is necessary to secure a space where the nozzle portion 300 can be arranged as the shape of the developing container 120, the toner storage portion 129 has to be configured to be small. On the other hand, according to the present embodiment, as shown in FIG. 2, since the capacity of the toner storage portion 129 can be configured to secure the maximum volume avoiding the optical path of the laser beam U, a large capacity can be realized.

[0091] Furthermore, by making the landing point of the hot melt resin HM an inclined surface inclined at a predetermined angle, the hot melt resin HM can be made to flow actively toward the desired region, so that toner sealing can be achieved with a small amount of hot melt resin, and cost reduction can also be realized.

[0092] In addition, in this embodiment, the viscosity of the hot melt resin HM is preferably between 600 mPa·s and 1200 mPa·s, but it is not limited thereto. Also, for the angles θ1 and θ2, 30° to 60° is preferred, but it is not limited thereto. Further, the first and second inclined surfaces 121c and 121d only need to be inclined at an angle smaller than 90 degrees with respect to the blade mounting surface 121b, and θ1>θ2 or θ1<θ2 may be satisfied.

Explanation of Reference Numerals

[0093] 106… Developing roller, 109… Developing unit, 120… Developing container, 121… Developing frame, 121a… Blade lower seal mounting surface, 121b… Blade mounting surface, 121c… First inclined surface, 121d… Second inclined surface, 121e… First wall portion, 121f… Second wall portion, 121g… Third wall portion, 121h… End seal mounting surface, 123… Developing space, 130… Developing blade, 130a … Support member, 130b… Elastic member, 132… Second notch portion, 160… Blade lower seal, 161c… First end surface, 200… End seal, 201… End surface, 204… Wedge portion, 210… Sheet member, 300… Injection device, HM… Hot melt resin, P… Landing point, Q… Space, S1… First communication portion, S2… Second communication portion

Claims

1. A frame body having a storage chamber for storing a developer and an opening communicating with the storage chamber, A developing roller supported by the frame body so as to face the opening and rotatably supported about a rotation axis, A regulating member for regulating the layer thickness of the developer carried on the outer peripheral surface of the developing roller, the regulating member being disposed along the direction of the rotation axis of the developing roller in a region on the downstream side in the rotation direction of the developing roller among the edge portions of the opening, and having a support portion whose end portion in the direction of the rotation axis is fixed to the frame body, and a sliding portion supported by the support portion and slidably contacting the outer peripheral surface of the developing roller on the upstream side of the support portion in the rotation direction, A first sealing member provided along the direction of the rotation axis so as to seal between the region on the downstream side among the edge portions of the opening and the support portion of the regulating member, A second sealing member provided along the rotation direction in a region outside the opening in the direction of the rotation axis and slidably contacting the end portion of the outer peripheral surface of the developing roller in the direction of the rotation axis, A developing unit comprising: The frame body is A first mounting surface to which the first sealing member is attached, A second mounting surface provided at a position spaced apart from the first mounting surface in the direction of the rotation axis, and to which the end portion of the support portion is attached, A third mounting surface provided at a position spaced apart from the first mounting surface and the second mounting surface in the upstream side in the rotation direction in the rotation direction, and to which the second sealing member is attached, And has The second sealing member sandwiches the end portion of the sliding portion of the regulating member on the rotation axis together with the developing roller, The first sealing member is attached to the first mounting surface so as to be spaced apart from each of the second mounting surface, the third mounting surface, and the second sealing member, and The second sealing member is attached to the third mounting surface so as to be spaced apart from each of the support portion of the regulating member, the first sealing member, the first mounting surface, and the second mounting surface, A space surrounded by the frame body, the regulating member, the first sealing member, and the second sealing member, and a space communicating between the storage chamber and the outside of the frame body through the opening is formed, And includes a sealing member filled in the space. Among the wall surfaces of the frame body that form the space, the region between the first mounting surface, the second mounting surface, and the third mounting surface is a concave portion that is recessed with respect to each of the first mounting surface, the second mounting surface, and the third mounting surface. In the concave portion, the region from the region between the first mounting surface and the second mounting surface to the third mounting surface includes an inclined surface that is inclined with respect to the second mounting surface. A developing unit characterized by this.

2. The inclined surface extends to a region close to the opening between the first mounting surface and the third mounting surface among the wall surfaces of the frame body that form the space. The sealing member has a first sealing portion that closes a communication portion that passes between the first mounting surface and the third mounting surface in the space and reaches the opening. The developing unit according to claim 1, characterized by this.

3. The inclined surface extends to a region close to the outside of the frame body between the second mounting surface and the third mounting surface among the wall surfaces of the frame body that form the space. The sealing member has a second sealing portion that closes a communication portion that passes between the second mounting surface and the third mounting surface in the space and reaches the outside of the frame body. Claim 1 or 2, characterized by this. The developing unit described.

4. The downstream end of the second sealing member in the rotational direction protrudes downstream of the third mounting surface. The inclined surface is characterized in that the gap between the inclined surface and the downstream end of the second sealing member in the rotational direction becomes narrower as it approaches the third mounting surface. The developing unit according to any one of claims 1 to 3, characterized by this.

5. The inclined surface is characterized in that the angle with respect to the second mounting surface changes stepwise toward the third mounting surface. The developing unit according to any one of claims 1 to 4, characterized by this.

6. The inclined surface is inclined at an angle smaller than 90 degrees with respect to the second mounting surface. The developing unit according to any one of claims 1 to 5, characterized by this.

7. The inclined surface has a region that is farther from the first sealing member than the first mounting surface and the second mounting surface in the normal direction of the second mounting surface. The developing unit according to any one of claims 1 to 6, characterized by this.

8. The support portion of the regulation member has a notch portion having a shape that is cut out such that a part of the inclined surface is exposed when viewed in the extending direction of the second mounting surface. The developing unit according to any one of claims 1 to 7, characterized in that.

9. The notch portion is provided at a position farther from the first seal member than the first mounting surface and the second mounting surface in the normal direction of the second mounting surface. The developing unit according to claim 8, characterized in that.

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