JP2015004873A - Developing device, process cartridge, image forming apparatus, and manufacturing method of developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device that can exhibit excellent seal performance while preventing the adhesion of toner at the ends in the axial direction of a developing roller.SOLUTION: A developing device 5 includes a developing roller 16, and end seals 18 located at the ends in the axial direction of the developing roller 16 to prevent the leakage of toner from the ends in the axial direction. The end seal 18 is formed of a material having a hardness during 40% constant compression of 50 N or more and 550 N or less. Each of the end seals 18 has a sheet-like slide member 26 attached to the side thereof, and the developing roller 16 is pressed against the end seals 18 with the sheet-like slide members 26 therebetween.

Description

  The present invention relates to a developing device, a process cartridge, an image forming apparatus, and a developing device manufacturing method.

  In a developing device of the type that uses toner, which is charged fine particles, as a developer and electrostatically attaches this toner to an electrostatic latent image, an opening that is inevitably formed around the developing roller From the toner. If the toner leaks from the developing device, the inside of the image forming apparatus main body equipped with the developing device becomes dirty, which may cause printing failure, or the operator's hand and clothes become dirty when the developing device is replaced. There was a thing.

  Therefore, conventionally, an end seal for preventing the toner from leaking from the both ends in the axial direction of the developing roller to the outside of the developing device is provided in the developing case, and this end seal is slid with the both ends in the axial direction of the developing roller. A structure that makes contact is proposed. This end seal needs to produce a moderate repulsive force against the developing roller while being appropriately compressed with the pressing of the developing roller, so it is formed of a relatively rigid foam or the like (both are patented) Reference 1).

  However, in the conventional configuration, the developing roller is pressed against an end seal formed of a material having an appropriate repulsive force (rigidity) so that the developing roller and the end seal are brought into close contact with each other. The pressure (sliding contact pressure) at the nip portion between the end seal and the end seal tends to increase. When the sliding contact pressure is high, the toner that has entered the nip portion between the developing roller and the end seal is heated, and in some cases, the heated toner may melt and cause sticking. When toner adheres to such a location, the end roller is pushed down more than necessary by the developing roller pushing the adhered toner toward the end seal, so that the gap between the end seal and the developing roller is reduced. May increase. Alternatively, the outer peripheral surface of the developing roller is scraped off with the adhered toner, and the gap between the end seal and the developing roller may increase. In this case, as the developing device is used, toner leakage from the developing device may easily occur. The phenomenon (problem) described above is particularly noticeable when the process speed of the developing device (the rotational speed of the developing roller) is high. Even if the process speed is not high, when using a toner having a lower melting point than in the past due to recent energy savings, the toner that has entered the high-pressure area (nip part) is heated by the sliding contact pressure and fixed. There is a risk.

  Therefore, in view of such circumstances, an object of the present invention is to provide a developing device capable of exhibiting excellent sealing performance while preventing toner from adhering to the axial end portion of the developing roller.

  The solution to the above problem is achieved by the developing device according to the present invention. That is, the developing device includes a developing roller and an end seal that is positioned at an axial end of the developing roller and prevents leakage of toner from the axial end. , Formed with a material having a hardness at 50% constant compression of 50 N or more and 550 N or less, a sheet-like sliding member is attached to the end seal side, and the developing roller is a sheet-like sliding member. Characterized by being pressed against the end seal through the moving member. In addition, "the hardness at the time of 40% constant compression" here means what is measured based on JISK6401.

  In the present invention, since the end seal is made of a very soft material that can be defined by the hardness at 40% constant compression, the repulsive force of the end seal in a state where the developing roller is pressed is weakened. Thus, the pressure at the nip portion between the developing roller and the end seal can be reduced. Accordingly, excessive heating of the toner that has entered the nip portion can be avoided, and the toner can be prevented from sticking. Therefore, it is possible to avoid a situation in which the developing roller rides on the fixed toner or a situation in which the developing roller is damaged, and an occurrence of an unnecessary gap between the developing roller and the end seal can be prevented. Further, in the present invention, the end seal is formed of a very soft material as described above, and a sheet-like sliding member is attached to the end seal side, and the developing roller is interposed via the sheet-like sliding member. Was pressed against the end seal. By disposing the sheet-like sliding member in this manner, in the state where the developing roller is pressed against the end seal, the end seal is crushed and the developing roller, the sheet-like sliding member, and the end seal are pressed. As a result, the sheet-like sliding member generates a repulsive force to the developing roller. Therefore, it is possible to obtain sufficient adhesion between the developing roller and the sheet-like sliding member without relying on the repulsive force of the end seal, thereby enabling excellent sealing performance to be exhibited. Become.

1 is a schematic diagram illustrating an embodiment of an image forming apparatus according to the present invention. It is a schematic sectional drawing which shows one Embodiment of the process cartridge which concerns on this invention. It is a principal part enlarged view which shows one Embodiment of the developing device which concerns on this invention. It is AA sectional drawing of the principal part shown in FIG. It is sectional drawing for demonstrating an example of the assembly | attachment aspect of a developing roller. (A) is an enlarged cross-sectional view of a main part for explaining the movement of toner particles between the developing roller and the sheet-like sliding member in the present invention, and (b) is no sheet-like sliding member. FIG. 6 is an enlarged cross-sectional view of a main part for explaining the movement of toner particles in the case. It is principal part sectional drawing of the developing device which concerns on other embodiment of this invention. It is principal part sectional drawing of the developing device which concerns on other embodiment of this invention. It is a principal part enlarged view of the developing device which concerns on other embodiment of this invention. It is BB sectional drawing of the principal part shown in FIG.

  Hereinafter, the present invention will be described with reference to the accompanying drawings. In the drawings for explaining the present invention, components such as members and components having the same function or shape are denoted by the same reference numerals as much as possible, and once described, the description will be given. Omitted.

  FIG. 1 is a schematic configuration diagram illustrating an embodiment of an image forming apparatus including a developing device and a process cartridge according to the present invention. First, the overall configuration and operation of the image forming apparatus will be described with reference to FIG.

  An image forming apparatus 1 shown in FIG. 1 includes a photoreceptor 2 as an image carrier that carries an image on the surface, a charging unit 3 that is disposed around the photoreceptor 2 and charges the surface of the photoreceptor 2, and a photoreceptor. Exposure means 4 for exposing the surface 2, a developing device 5 for visualizing the electrostatic latent image on the photoreceptor 2, and a visible image (toner image) on the photoreceptor 2 on a sheet S as a transfer sheet. A transfer unit 6 for transferring, a cleaning unit 7 for cleaning the surface of the photoreceptor 2, and a fixing unit 8 for fixing the transferred image to the paper S are provided. The transfer means 6 includes an intermediate transfer belt 9, a primary transfer roller 10 that presses the intermediate transfer belt 9 against the photosensitive member 2, a secondary transfer roller 11, and a motor (not shown) that rotationally drives the intermediate transfer belt 9 in a predetermined direction. And have. In the present embodiment, among these, the photosensitive member 2, the charging unit 3, the developing device 5, and the cleaning unit 7 constitute a process cartridge 12 (see FIG. 2), which is detachable from the main body of the image forming apparatus 1. Has been.

  In addition, a plurality of process cartridges 12 having the above-described configuration are installed corresponding to, for example, each color of yellow, cyan, magenta, and black. In this embodiment, the process cartridge 12 is arranged along the moving direction (longitudinal direction) of the intermediate transfer belt 9. Four process cartridges 12 for each color are arranged in parallel.

  Next, an image forming operation of the image forming apparatus 1 according to the present embodiment will be described with reference to FIG. When the image forming operation is started, the photosensitive member 2 is rotationally driven, and the surface of the photosensitive member 2 is uniformly charged by the charging unit 3 so as to have a predetermined polarity. Then, based on image information sent from a reading unit (not shown) or print data sent from a PC electrically connected to the image forming apparatus 1, the exposure of the exposure unit 4 performs exposure of the photosensitive member 2. An electrostatic latent image is formed on the surface (charged surface). By supplying toner to the electrostatic latent image formed on the photoreceptor 2 in this way by the developing device 5, the electrostatic latent image is visualized (visualized) as a toner image. Then, the toner image on the photoreceptor 2 sequentially forms a visible image on the intermediate transfer belt 9 between each photoreceptor 2 and the transfer unit 6 (intermediate transfer belt 9). Specifically, a visible voltage visualized on the surface of each photoconductor 2 by applying a predetermined voltage (primary transfer bias) from a high voltage power source (not shown) between the primary transfer roller 10 and the photoconductor 2. The image is transferred to the surface of the intermediate transfer belt 9. In this way, a visible image of each color is transferred in sequence on the surface of the intermediate transfer belt 9, thereby forming a full-color image.

  The full-color image transferred and formed on the intermediate transfer belt 9 is transferred to the paper S by applying a predetermined voltage (secondary transfer bias) between the secondary transfer roller 11 and the intermediate transfer belt 9. . Thereafter, the sheet S on which the toner image is transferred is conveyed to the fixing unit 8 and is heated and pressed to fix the toner image on the sheet S. The sheet S on which the image is fixed is conveyed further downstream of the fixing unit 8 and discharged (output) out of the image forming apparatus 1.

  The above description is an image forming operation when a four-color full-color image is formed on the paper S. A single-color image can be formed using any one of the four process cartridges 12, or two or three. It is also possible to form a two-color or three-color image using a single process cartridge 12. Of course, an image having five or more process cartridges 12 can form a single color image to five or more colors by an image forming operation similar to the above.

  Next, the configuration of the developing device 5 according to the present invention will be described with reference to FIG. As shown in FIG. 2, the developing device 5 includes a toner storage chamber 13 that stores toner as a one-component developer, a toner supply chamber 14 adjacent to the toner storage chamber 13, and the toner storage chamber 13 and the toner supply. A developing case 15 that defines each chamber 14, a developing roller 16 that is attached to the developing case 15 and that contacts the photosensitive member 2, and contacts the developing roller 16, and the toner supplied from the toner supply chamber 14 is supplied to the developing roller 16. And an end seal 18 (see FIG. 3) that is in sliding contact with the axial end of the developing roller 16 and prevents leakage of toner from the axial end. In the present embodiment, the developing device 5 includes a regulating blade 19 that slidably contacts the developing roller 16 and regulates toner adhesion to the developing roller 16, and a portion of the developing roller 16 that comes into contact with the photoreceptor 2 from the developing roller 16. And an inlet seal 20 for preventing toner leakage between the developing roller 16 and the developing case 15.

  In addition, an agitation assisting member 21 that assists in agitating the toner is disposed in the toner supply chamber 14, and the agitation assisting member 21 is pressed against the regulation blade 19 to assist the agitation via the regulation blade 19. The regulating blade 19 is pressed toward the developing roller 16 located on the side opposite to the member 21. A partition wall 22 is provided between the toner storage chamber 13 and the toner supply chamber 14, and a toner for adjusting the amount of toner supplied from the toner storage chamber 13 to the toner supply chamber 14 is provided on the partition wall 22. A supply port 23 is provided. The toner supply port 23 may be always open or may be opened and closed by a sliding operation of a shutter (not shown). The toner storage chamber 13 is rotatably provided with an agitator 24 for preventing or suppressing toner aggregation by stirring.

  The supply roller 17 is formed of a material having a structure in which a surface layer portion has a hole portion on the surface thereof, such as a foam. As a result, the toner conveyed into the toner supply chamber 14 is efficiently attached and taken in, and the toner attached to the surface can be supplied to the surface of the developing roller 16. In addition, the electrical resistance value of the supply roller 17 (surface layer portion thereof) is set to, for example, the third power to the fourth power Ω.

  A voltage offset to the same polarity as the toner charging polarity with respect to the potential of the developing roller 16 is applied to the supply roller 17 as a supply bias. This supply bias acts in such a direction that the toner preliminarily charged at the contact portion with the developing roller 16 is pressed against the developing roller 16. Of course, the polarity of the voltage applied to the supply roller 17 is not limited to the above type, and depending on the type of toner, the polarity can be the same as or opposite to that of the developing roller 16.

  The developing roller 16 is formed by covering the outer surface with a surface layer portion 25 having a predetermined elasticity, and a film (not shown) made of a material that is easily charged with a polarity opposite to that of the toner is formed on the surface of the surface layer portion 25. Is formed. Here, in order to keep the contact state with the photoreceptor 2 as uniform as possible, the surface layer portion 25 is formed of, for example, a material (for example, rubber) having a JIS-A hardness standard of 50 degrees or less and has a developing bias. In order to act, the electric resistance value is set to the third power to the tenth power.

  The surface roughness of the surface of the developing roller 16 (that is, the outer peripheral surface of the surface layer portion 25 of the developing roller 16) is set to, for example, Ra not less than 0.2 μm and not more than 2.0 μm. It can be held on the surface.

  The regulating blade 19 is formed of a metal plate spring material such as SUS304CSP, SUS301USP, or phosphor bronze, for example, and a free end thereof is brought into contact with the surface of the developing roller 16. By contacting the developing roller 16 in this manner, the toner layer attached to the surface of the developing roller 16 can be given a predetermined thickness, and the toner can be charged by frictional charging. At this time, the pressing force of the regulating blade 19 against the developing roller 16 is adjusted to a range of 10 N / m or more and 100 N / m or less in consideration of, for example, a pressing force by the stirring assisting member 21.

  In addition, a voltage that is offset to the same polarity as the charging polarity of the toner with respect to the potential applied to the developing roller 16 is applied to the regulating blade 19 as a regulating bias in order to assist frictional charging. .

  As the toner stored (filled) in the toner storage chamber 13 of the developing device 5, for example, a toner manufactured by a pulverization method or a polymerization method is used. Further, the toner manufactured by the above-described method can be used as an external additive having silica fine particles impregnated with silicon oil adhered thereto. By using the toner having the silica fine particles attached thereto, it contributes to improvement in cleaning properties and transfer efficiency, and in turn, to extending the life of the developing device 5 (including the process cartridge 12).

  Next, the developing operation of the developing device 5 according to the present embodiment will be described with reference to FIG. First, the supply roller 17 is rotated in a predetermined direction, and the toner adhered to the surface thereof is conveyed to a contact portion with the developing roller 16, whereby the conveyed toner is supplied to the surface of the developing roller 16. Then, the developing roller 16 is rotated in the same direction as the supply roller 17, and the toner held on the surface of the developing roller 16 passes through the nip portion with the regulating blade 19 and is conveyed to a position facing the photoreceptor 2. As a result, the toner thinned to a predetermined thickness is supplied to the position facing the photoreceptor 2 by the rotation of the developing roller 16. Then, the photosensitive member 2 is rotated in the opposite direction to the developing roller 16, and the surface of the developing roller 16 is moved in the same direction as the surface of the photosensitive member 2 at a position facing the photosensitive member 2. As a result, the toner held in a thin layer on the surface of the developing roller 16 is changed into a developing bias applied to the developing roller 16 and a latent image electric field formed by the electrostatic latent image on the photoreceptor 2. Accordingly, it moves to the surface of the photoreceptor 2 and is developed.

  Hereinafter, the structure around the end seal 18 will be described in detail.

  3 and 4 show the periphery of the end seal 18 located at the end of the developing roller 16 in the axial direction. 3 is a view of the periphery of the end seal 18 as viewed from a direction orthogonal to the rotation axis of the developing roller 16, and FIG. 4 is a cross-sectional view of the developing roller 16 and the end seal 18 (A-A cross-sectional view of FIG. 3). ). As shown in FIGS. 3 and 4, the developing roller 16 and the regulating blade 19, and the developing roller 16 and the inlet seal 20 are in contact with each other at the axial end of the developing roller 16.

  Here, the end seal 18 is attached to the developing case 15 and has a hardness at a constant 40% compression of 50 N or more and 550 N or less, preferably 100 N or more and 250 N or less, more preferably 150 N degrees or more and 220 N ( It is made of a material having a median value of 200 N) or less. Specifically, foams such as urethane foam and rubber sponge, or gel-like substances that can exhibit the above-mentioned hardness can be used, and among them, a sponge mainly composed of rubber such as EPDM is preferably used. Is possible.

  A sheet-like sliding member 26 is attached to the end seal 18 side, and the developing roller 16 is pressed against the end seal 18 via the sheet-like sliding member 26. The sheet-like sliding member 26 is formed of a stretchable material, and has a stretchability enough to be extended along with a pressing operation to the end seal 18 of the developing roller 16 described later. More specifically, as the sheet-like sliding member 26, one having an elongation of 10% or more, preferably 20% or more, more preferably 50% or more is used.

  In terms of material, the sheet-like sliding member 26 is formed of a material having excellent sliding properties, for example, a fluorine-based resin such as Teflon (registered trademark) in consideration of the toner dischargeability described later. It may be done. Specifically, it may be formed of a material having a static friction coefficient of 0.4 or less. The value of the static friction resistance at this time is measured by, for example, Tribogear Muse 94iHEIDON manufactured by Shinto Kagaku Co., Ltd. At this time, it is desirable that the surface of the sheet-like sliding member 26 has a smoothness that does not capture at least toner particles 27 (see FIG. 6 described later).

  The sheet-like sliding member 26 may have a thickness of 200 μm or less (more preferably 40 μm or less).

  As shown in FIG. 4, the sheet-like sliding member 26 having the above-described configuration has an adhesive surface 26a on at least one of the front and back surfaces at both ends, and the adhesive surface 26a is connected to the end seal 18 or the end seal 18a. It is attached to the end seal 18 side by sticking it to the developing case 15 that holds the part seal 18. The developing roller 16 is pressed against the end seal 18 through the sheet-like sliding member 26 attached in this manner. As a result, the developing roller 16 and the sheet-like sliding member 26, and the sheet-like sliding member 26 and the end seal 18 are in close contact with each other, and the developing roller 16 is in direct sliding contact with the end seal 18. Without being slidable to the sheet-like sliding member 26.

  Below, an example of the assembly | attachment process of the developing roller 16 for obtaining the said sliding contact state is demonstrated based on FIG.

  First, as shown in FIG. 5, the sheet-like sliding member 26 is disposed on the end seal 18. In the present embodiment, both end portions of the end seal 18 are fixed so as to float from the curved surface of the end seal 18. Then, by pressing the developing roller 16 toward the end seal 18, the sheet-like sliding member 26 that is lifted from the surface (curved surface) of the end seal 18 is pushed out. As a result, the end seal 18 is compressed and deformed, and the sheet-like sliding member 26 is pushed and extended, and the developing roller 16 and the sheet-like sliding member 26, and the sheet-like sliding member 26 and the end The part seal 18 is in close contact with each other. At this time, the sheet-like sliding member is stretched to generate a force (repulsive force) to return to the original state, and the repulsive force causes the adhesion between the developing roller 16 and the sheet-like sliding member 26. improves. As described above, the assembly process of the developing roller 16 is completed. As described above, when the developing roller 16 is assembled, the sheet-like sliding member 26 has different elongations in a region having the bonding surfaces 26a at both ends and a region having no bonding surfaces 26a. That is, since the region having the adhesive surface 26 a is fixed to the end seal 18 side, the development roller 16 is not pressed and stretched. On the other hand, the region having no adhesive surface 26a, in this embodiment, the region excluding both ends of the sheet-like sliding member 26 is not fixed to any member. Arise. Therefore, depending on the material of the sheet-like sliding member 26, the assembly mode of the developing roller 16 can be determined by viewing the sheet-like sliding member 26 with the developing roller 16 removed after assembly. Is possible.

  Thus, in the present invention, the end seal 18 is formed of a very soft material that can be defined by the hardness at 40% constant compression, so that the end portion in a state where the developing roller 16 is pressed is formed. The repulsive force of the seal 18 can be weakened, and the pressure at the nip portion between the developing roller 16 and the end seal 18 can be reduced. Accordingly, excessive heating of the toner that has entered the nip portion can be avoided, and the toner can be prevented from sticking. Therefore, the developing roller 16 and the end seal 18 are prevented from being pushed by the developing roller toward the end seal to avoid the end seal being pushed down more than necessary or the developing roller 16 being damaged. It is possible to prevent a situation in which an unnecessary gap is generated between the two. Further, in the present invention, the end seal 18 is formed of a very soft material as described above, and a sheet-like sliding member 26 is attached to the end seal 18 side, and the sheet-like sliding member 26 is attached to the end seal 18. The developing roller 16 is pressed against the end seal 18. By disposing the sheet-like sliding member 26 in this manner, in a state where the developing roller 16 is pressed against the end seal 18, the end seal 18 is crushed and the developing roller 16 and the sheet-like sliding member are pressed. 26 and the end seal 18 are clogged, and a repulsive force to the developing roller 16 is generated in the sheet-like sliding member 26 by being pressed. Therefore, sufficient adhesion can be obtained between the developing roller 16 and the sheet-like sliding member 26 without depending on the repulsive force of the end seal 18, thereby exhibiting excellent sealing performance. Is possible.

  In this embodiment, as the sheet-like sliding member, a member having elasticity, specifically, a member exhibiting an elongation rate of 10% or more is used. Therefore, the developing roller is provided on the sheet-like sliding member. When pressed and stretched, a repulsive force that can be brought into close contact with the surface of the developing roller 16 can be generated. As a result, the adhesion between the developing roller 16 and the sheet-like sliding member 26 can be further enhanced to further improve the sealing performance.

  At this time, as in this embodiment, both ends of the end seal 18 are fixed so as to be lifted from the curved surface of the end seal 18, and then the developing roller 16 is moved to the end. The sheet-like sliding member 26 that is pressed toward the seal 18 and lifted from the surface (curved surface) of the end seal 18 is pushed and extended without being affected by the compressive deformability of the end seal 18. The sheet-like sliding member 26 can be sufficiently extended. This makes it possible to adjust the repulsive force generated by pushing and extending the sheet-like sliding member 26 and apply a predetermined nip pressure between the developing roller 16 and the sheet-like sliding member 26. .

  Further, since the end seal 18 is made of a very soft material that can be defined by the hardness at 40% constant compression, when the end seal 18 is attached to the developing case 15, the developing roller 16 When the sheet-like sliding member 26 is directly attached to the end seal 18 from the original structural point of view (surface opening portion), the curved surface serving as the pressing surface of the sheet is undulated. Following this, it is difficult to attach the sheet-like sliding member 26 in a smooth state. On the other hand, as described above, after the sheet-like sliding member 26 is disposed on the end seal 18, preferably at a position floating from the end seal 18, the developing roller 16 is directed toward the end seal 18. When the sheet-like sliding member 26 is pushed and stretched, the sheet-like sliding member 26 comes into contact with the end seal 18 in the stretched state. Therefore, a smooth state can be maintained without being affected by the surface shape of the end seal 18, and the surface can be brought into close contact with the surface (outer peripheral surface) of the developing roller 16. As a result, the slidable contact surface with the developing roller 16 can be smoothed to make the nip pressure uniform.

  Further, in this embodiment, since the sheet-like sliding member 26 having excellent slidability is used, the dischargeability of the toner particles 27 at the nip portion with the developing roller 16 can be improved. Hereinafter, this will be described in detail with reference to FIG.

  When the end seal 18 is formed of a foamed material such as sponge or urethane foam in order to give a predetermined compressive deformability as the end seal 18, the surface of the end seal 18 in contact with the toner (development) A large number of surface openings are also present on the slidable contact surface with the roller 16. Therefore, as shown in FIG. 6B, the toner particles 27 that have entered between the developing roller 16 and the end seal 18 as the developing roller 16 rotates, enter the inside from the surface opening of the end seal 18. It can get in and get caught. Since the toner particles 27 trapped in the end seal 18 are continuously subjected to heat and pressure generated by the sliding contact between the end seal 18 and the developing roller 16, there is a possibility that the toner particles 27 melt and be fixed. On the other hand, in the present invention, as shown in FIG. 6A, a sheet-like sliding member 26 is disposed on the end seal 18 side, and development is performed via the sheet-like sliding member 26. Since the roller 16 is pressed against the end seal 18, the surface of the end seal 18, particularly the area pressed against the developing roller 16, is covered with a sheet-like sliding member 26. As a result, it is possible to prevent the toner particles 27 from being trapped in the end seal 18, and to avoid melting and eventually sticking due to continuous sliding contact or pressing pressure at a fixed position.

  In particular, in the present embodiment, since the sheet-like sliding member 26 has a smooth surface and is formed of a fluorine resin, more specifically, the static friction coefficient is 0. 4 or less is used, so that the toner particles 27 that have entered between the developing roller 16 and the sheet-like sliding member 26 are smoothly developed without being caught by the sheet-like sliding member 26. It can pass between the roller 16 and the sheet-like sliding member 26 (nip part). Therefore, it is possible to more effectively prevent the toner from adhering to the nip portion.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the above-mentioned embodiment, Of course, a various change can be added in the range which does not deviate from the summary of this invention.

  For example, regarding the arrangement of the sheet-like sliding member 26, as shown in FIG. 7, the sheet-like sliding member 26 is placed between the end seal 18 and the regulating blade 19 so as to span the end seal 18. You may make it attach to the side. In this case, by fixing the adhesive surface 26a of the sheet-like sliding member 26 to the surface of the regulating blade 19 on the developing roller 16 side, as shown in FIG. And abuts against the axial end of the developing roller 16. For this reason, the toner can easily flow along the rotation direction of the developing roller 16 even at the contact position with the regulating blade 19, thereby more effectively preventing the toner from leaking out of the developing device 5. Is possible.

  The above configuration can be similarly applied to the inlet seal 20. For example, as shown in FIG. 8, the sheet-like sliding member 26 is end-mounted so as to span between the end seal 18 and the inlet seal 20. You may make it attach to the part seal 18 side. In this case, by fixing the adhesive surface 26a of the sheet-like sliding member 26 to the surface of the inlet seal 20 on the side of the developing roller 16, the inlet seal 20 is attached to the sheet-like sliding member 26 as shown in FIG. And abuts against the axial end of the developing roller 16. For this reason, the toner easily flows along the rotation direction of the developing roller 16 even at the position where it abuts the inlet seal 20, thereby more effectively preventing the toner from leaking out of the developing device 5. Is possible.

  Further, for the purpose of reducing the nip pressure between the regulating blade 19 and the developing roller 16, for example, as shown in FIG. 9, a notch portion 28 is provided at a position of the end seal 18 that contacts the free end of the regulating blade 19. You may make it provide. By configuring the end seal 18 in this way, the contact pressure between the regulating blade 19 and the end seal 18 can be eliminated, and accordingly, the contact pressure between the regulating blade 19 and the developing roller 16 is reduced. be able to. Accordingly, excessive heating of the toner that has entered the nip portion can be avoided, and the toner can be prevented from sticking.

  At this time, the sheet-like sliding member 26 may be attached to the end seal 18 so as to span the end seal 18 and the regulating blade 19 and cover the notch 28. Good. As a result, a gap newly formed between the regulating blade 19 and the notched portion 28 can be covered with the sheet-like sliding member 26. Therefore, it is possible to prevent the leakage of toner from the gap while reducing the contact pressure between the developing roller 16 and the regulating blade 19.

  In addition, the developing device 5 according to the present invention is of course applicable to the process cartridge 12 and the image forming apparatus 1 other than those illustrated.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Photoconductor 3 Charging means 4 Exposure means 5 Developing apparatus 6 Transfer means 7 Cleaning means 8 Fixing means 9 Intermediate transfer belt 10 Primary transfer roller 11 Secondary transfer roller 12 Process cartridge 13 Toner storage chamber 14 Toner supply chamber 15 Developing case 16 Developing roller 17 Supply roller 18 End seal 19 Restriction blade 20 Entrance seal 26 Sliding member 26a Adhesive surface 27 Toner particle 28 Notch S Paper

JP 2001-22179 A

Claims (10)

In a developing device comprising a developing roller and an end seal located at an axial end of the developing roller and preventing leakage of toner from the axial end.
The end seal is formed of a material having a hardness at 40% constant compression of 50 N or more and 550 N or less,
A developing device, wherein a sheet-like sliding member is attached to the end seal side, and the developing roller is pressed against the end seal via the sheet-like sliding member.   The developing device according to claim 1, wherein the sheet-like sliding member exhibits an elongation percentage of 10% or more.   The developing device according to claim 1, wherein the sheet-like sliding member has a smooth surface and is made of a fluorine-based resin.   The developing device according to claim 1, wherein the sheet-like sliding member has a coefficient of static friction of 0.4 or less. A regulating blade that slidably contacts the developing roller and regulates the adhesion of the toner to the developing roller;
The developing device according to claim 1, wherein the sheet-like sliding member is attached to the end seal side so as to span between the end seal and the regulating blade. An inlet seal located on the downstream side in the rotation direction of the developing roller from a portion of the developing roller that contacts the photoreceptor;
The developing device according to claim 1, wherein the sheet-like sliding member is attached to the end seal side so as to span between the end seal and the inlet seal. Of the end seal, a notch is provided at a location where it comes into contact with the free end of the regulating blade,
The sheet-like sliding member is attached to the end seal side so as to span between the end seal and the regulating blade and cover the notch. Development device.   A process cartridge comprising a photoconductor and the developing device according to claim 1.   An image forming apparatus comprising the process cartridge according to claim 8. In a method for manufacturing a developing device, comprising: a developing roller; and an end seal that is in sliding contact with an axial end of the developing roller and prevents toner leakage from the axial end.
A sheet-like sliding member having excellent stretchability is disposed on the end seal, and then the developing roller is pressed against the end seal to extend the sheet-like sliding member. A method of manufacturing a developing device.

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