The present invention relates to a developing apparatus that develops an electrostatic latent image formed on a photosensitive drum, a process cartridge that forms a developer image on the photosensitive drum and is detachably attached to an apparatus main body of an image forming apparatus, and the image forming apparatus that forms an image on a recording medium by using a developer.
Conventionally, in an image forming apparatus that uses electrophotographic techniques, a photosensitive drum charged by a charging roller is exposed by an exposure apparatus, and an electrostatic latent image is thereby formed on the photosensitive drum. The electrostatic latent image formed on the photosensitive drum is developed as a toner image by a developing apparatus, and the toner image on the photosensitive drum is transferred to a sheet such as a paper sheet. Subsequently, the toner image transferred to the sheet is fixed to the sheet by being heated and pressurized by a fixing apparatus.
Herein, in recent years, the charging roller, the photosensitive drum, the developing apparatus and the like are integrated as a process cartridge in the image forming apparatus. In addition, the process cartridge is detachably attached to the apparatus main body of the image forming apparatus. With this, by replacing the process cartridge, it is possible to perform, for example, replacement of process means such as the photosensitive drum and addition of toner. According to the process cartridge system described above, a user can perform the maintenance of the image forming apparatus, and hence it is possible to easily perform the maintenance of the image forming apparatus.
Herein, the frame of the developing apparatus in the process cartridge is conventionally formed by coupling a first frame and a second frame. In addition, by coupling the first frame and the second frame, a toner storage portion in which toner is stored, a developing chamber in which a developing roller is disposed, and an opening for conveying the toner from the toner storage portion to the developing chamber are formed in the developing apparatus. Further, conventionally, a seal member is provided in a gap between the developing roller and the frame in the vicinity of each of both end portions in the direction of the rotation center axis of the developing roller such that the toner does not leak from the gap between the developing roller and the frame.
In addition, conventionally, due to the displacement of the position of the seal member relative to the frame that is caused when the developing apparatus is assembled and the tolerance of the seal member, a gap has been formed between the seal member and the frame. To cope with this, in a technique disclosed in Japanese Patent Application Laid-open No. 2007-025345, in order to seal the gap between the seal member and the frame, elastomer is injected into the gap between the seal member and the frame. Specifically, an injection inlet for injecting liquid elastomer is provided in the frame, and the elastomer is poured into the gap between the seal member and the frame by injecting the elastomer into the injection inlet.
In the case of this configuration, it is proposed to adopt a configuration in which a fence for storing the elastomer spilling out of the injection inlet is provided (Japanese Patent Application Laid-open No. 2007-025345). The elastomer having spilled out of the injection inlet is stored in the fence provided around the injection inlet. With this, the injected elastomer is prevented from jutting out from the contour of the frame.
In recent years, the size of the image forming apparatus has been reduced. In order to reduce the size of the image forming apparatus, it is conceivable to adopt a configuration in which the fence for storing the elastomer is exposed to the path of the sheet conveyed in the image forming apparatus. However, when the elastomer or the fence for storing the elastomer is exposed to the path of the sheet, in the case where the sheet is curled, there is a possibility that the sheet comes into contact with the elastomer or the fence and jamming (paper jamming) is thereby caused.
In order to achieve the above object, a developing apparatus as the present invention is a developing apparatus forming a developer image with a developer including a developer bearing member that carries the developer, a frame in which the developer bearing member is provided, a seal member that seals a gap between the developer bearing member and the frame such that the developer does not leak from the gap between the developer bearing member and the frame, and a sealing portion that seals a gap between the frame and the seal member such that the developer does not leak from the gap between the frame and the seal member, wherein the frame is provided with an injection inlet for injecting elastomer for forming the sealing portion, a storage portion in which the elastomer spilling out of space in which the sealing portion is formed is stored, and a protruding portion that protrudes toward a conveyance path of a recording medium to which the developer image is transferred, and the protruding portion protrudes toward the conveyance path further than the storage portion exposed to the conveyance path.
In addition, in order to achieve the above object, a process cartridge as the present invention is a process cartridge detachably attached to an apparatus main body of an image forming apparatus, the process cartridge including an image bearing member on which a developer image is formed, a developer bearing member that carries a developer and develops the image bearing member, a frame in which the developer bearing member is provided, a seal member that seals a gap between the developer bearing member and the frame such that the developer does not leak from the gap between the developer bearing member and the frame, and a sealing portion that seals a gap between the frame and the seal member such that the developer does not leak from the gap between the frame and the seal member, wherein the frame is provided with an injection inlet for injecting elastomer for forming the sealing portion, a storage portion in which the elastomer spilling out of space in which the sealing portion is formed is stored, and a protruding portion that protrudes toward a conveyance path of a recording medium to which the developer image is transferred, and the protruding portion protrudes toward the conveyance path further than the storage portion exposed to the conveyance path.
Further, in order to achieve the above object, an image forming apparatus as the present invention is an image forming apparatus including an image bearing member on which a developer image is formed, a developer bearing member that carries a developer and develops the image bearing member, a frame in which the developer bearing member is provided, a seal member that seals a gap between the developer bearing member and the frame such that the developer does not leak from the gap between the developer bearing member and the frame, and a sealing portion that seals a gap between the frame and the seal member such that the developer does not leak from the gap between the frame and the seal member, wherein the frame is provided with an injection inlet for injecting elastomer for forming the sealing portion, a storage portion in which the elastomer spilling out of space in which the sealing portion is formed is stored, and a protruding portion that protrudes toward a conveyance path of a recording medium to which the developer image is transferred, and the protruding portion protrudes toward the conveyance path further than the storage portion exposed to the conveyance path.
Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings).
Hereinafter, a description will be given, with reference to the drawings, of embodiments (examples) of the present invention. However, the sizes, materials, shapes, their relative arrangements, or the like of constituents described in the embodiments may be appropriately changed according to the configurations, various conditions, or the like of apparatuses to which the invention is applied. Therefore, the sizes, materials, shapes, their relative arrangements, or the like of the constituents described in the embodiments do not intend to limit the scope of the invention to the following embodiments.
Hereinbelow, the embodiment will be described in detail by using the drawings. First, the overall configuration of an image forming apparatus X and an image forming process will be described by using
Note that, in the present embodiment, the direction of the rotation center axis of an electrophotographic photosensitive drum (hereinafter referred to as a drum 62) as an image bearing member is a longitudinal direction. In addition, a direction that is orthogonal to the longitudinal direction and corresponds to the direction of an arrow C in
<Overall Configuration of Image Forming Apparatus X>
The image forming apparatus X shown in
<Image Forming Process>
Next, an image forming process will be described. In the case where the image forming process is executed, first, the drum 62 is rotationally driven in a direction of an arrow R at a predetermined circumferential speed (process speed) based on a print start signal. A charging roller 66 to which a bias voltage is applied comes into contact with the outer peripheral surface of the drum 62, and uniformly charges the outer peripheral surface of the drum 62. The exposure apparatus 3 outputs a laser beam L in accordance with image information. Scanning exposure is performed on the outer peripheral surface of the drum 62 with the laser beam L. With this, the electrostatic latent image corresponding to the image information is formed on the outer peripheral surface of the drum 62.
On the other hand, as shown in
In addition, as shown in
The sheet P to which the toner image is transferred is separated from the drum 62, and is guided by the conveyance guide 8 and conveyed to the fixing apparatus 9. Subsequently, the sheet P passes through a nip portion of the heat roller 9a and the pressure roller 9b in the fixing apparatus 9. In the nip portion, the sheet P is pressurized and heated, and the toner image is thereby fixed to the sheet P. The sheet P to which the toner image is fixed is conveyed toward the discharge roller pair 10, and is discharged to the discharge tray 11 by the discharge roller pair 10.
On the other hand, as shown in
<With Regard to Attachment and Detachment of Cartridge B>
Next, attachment and detachment of the cartridge B to and from the apparatus main body A will be described by using
<Overall Configuration of Cartridge B>
Next, the overall configuration of the cartridge B will be described by using
First, the configuration of the cartridge B will be described by using
On the other hand, the cleaning unit 60 is constituted by the cleaning frame 71, the drum 62, the charging roller 66, the cleaning blade 77 and the like. In the cleaning frame 71, a first supporting portion 71c and a second supporting portion 71d for rotatably supporting the developing apparatus unit 20 are provided. As shown in
Further, a drum bearing 73 is fixed to the cleaning frame 71, whereby the drum 62 is rotatably supported, and the developing apparatus unit 20 and the cleaning unit 60 are positioned in the longitudinal direction. In addition, in the side member 26, a biasing member 46a is provided on the driving side. In the toner storage frame 21, a biasing member 46b is provided on the non-driving side. The biasing member 46a is configured so as to abut on a spring seat 71e provided in the cleaning frame 71, and the biasing member 46b is configured so as to abut on a spring seat 71f provided in the cleaning frame 71. With this, the developing apparatus unit 20 is reliably biased in a direction toward the cleaning unit 60. In addition, as shown in
<Configuration of Cleaning Unit>
Next, the configuration of the cleaning unit 60 will be described by using
A shaft portion 66b of the charging roller 66 is biased in a direction toward the drum 62 and is rotatably supported by a bearing member (not shown) attached to the cleaning frame 71. The drum 62 is integrally coupled to a flange 64 and a flange 63 to thereby constitute a drum unit 61. Note that the method for coupling the drum 62 to the flanges 64 and 63 includes swaging, bonding, welding and the like.
In addition, to the flange 64, a grounding contact (not shown) or the like is coupled. Further, in the flange 63, the driving force receiving portion 63a that receives the driving force from the apparatus main body A, a gear portion 63b that transmits the driving force to the developing roller 32, and a supported portion 63c that is rotatably supported by the drum bearing 73 are provided. In the drum unit 61, the supported portion 63c is supported by a supporting portion 73a of the drum bearing 73, and the supported portion 64a of the flange 64 is rotatably supported by being supported by a drum shaft 78 that is press-fitted into the cleaning frame 71.
<With Regard to Configuration of Developing Apparatus Unit 20>
Next, the configuration of the developing apparatus unit 20 according to the present embodiment will be described. First, the schematic configuration of developing means or the like that constitutes the developing apparatus unit 20 will be described by using
(Schematic Description of Developing Apparatus Unit)
The developing blade 42 is constituted by a supporting member 42a formed of sheet metal and an elastic member 42b formed of an elastic material such as urethane rubber, and both ends thereof are fixed to the toner storage frame 21 at predetermined positions using screws (not shown). In addition, the elastic member 42b abuts on the developing roller 32, whereby the amount of the toner on the outer peripheral surface of the developing roller 32 is controlled and a triboelectric charge is provided to the toner.
A developing roller unit 31 is constituted by the developing roller 32, the magnet roller 34 (see
(With Regard to Configurations of Frame and Seal Member 47 of Developing Apparatus Unit 20)
Next, the configuration of each of the toner storage frame 21, the lid member 22, and a seal member 47 according to the present embodiment will be described. First, the seal member 47 will be described by using
As described above, with regard to a developing frame that constitutes the developing apparatus unit 20, by welding the toner storage frame 21 as the first frame having the developing opening 21a and the lid member 22 as the second frame together, the toner storage portion 20a and the developing chamber 20c are formed (see
As shown in
Next, elastomer as a liquid injected member and a paper conveying rib 22e as a protruding portion according to the present embodiment will be described by using
In the present embodiment, as shown in
In addition, in the present embodiment, as shown in
As shown in
Thus, in the present embodiment, the paper conveying rib 22e protrudes toward the paper path S further than the buffer portion 22d such that the sheet P does not come into contact with the buffer portion 22d. With this, in the case where the buffer portion 22d is exposed to the path of the sheet P, it is possible to prevent the sheet P from coming into contact with the buffer portion 22d to thereby cause the jamming.
In addition, in the present embodiment, the paper conveying rib 22e is capable of guiding the sheet P toward the direction in which the sheet P is to be conveyed.
Further, in the present embodiment, the paper conveying rib 22e approaches the paper path S as the paper conveying rib 22e extends in the conveyance direction of the sheet P. With this, it is possible to guide the sheet P toward the direction in which the sheet P is to be conveyed.
In addition, in the present embodiment, the paper conveying rib 22e is formed by extending part of the buffer portion 22d toward the paper path S. Part of the buffer portion 22d serves as the paper conveying rib 22e, whereby it is possible to save a material for forming the paper conveying rib 22e.
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.
This application claims the benefit of Japanese Patent Application No. 2016-118005, filed Jun. 14, 2016, which is hereby incorporated by reference herein in its entirety.
Number | Date | Country | Kind |
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2016-118005 | Jun 2016 | JP | national |