Developing device and image forming apparatus equipped with same

Abstract

To provide a developing device that can prevent outflow of developer.SOLUTION: A developing device comprises a developer container, a developer carrier, a regulation blade, and a blade seal member. The developer container has an opening. The developer carrier is rotatably supported on the developer container and has a developing area in which part of an outer peripheral surface carrying developer is exposed from the opening and faces an image carrier. The regulation blade is arranged on the upstream side of the developing area in a rotation direction of the developer carrier. The developer container has a blade opposing part that is opposite to a surface of the regulation blade on the upstream side in a rotation direction. The regulation blade has a fixed part that is opposite to the blade opposing part and fixed to the developer container, and a regulation part that projects toward the developer carrier from the fixed part. The interval between the regulation part and the blade opposing part is larger than the interval between the fixed part and the blade opposing part. The blade seal member is bonded to a surface on the upstream side of the regulation part with respect to the rotation direction.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a developing device and an image forming apparatus equipped with the same. [Background technology]

[0002] Electrophotographic image forming apparatuses such as copiers, printers, facsimiles, and combination machines thereof are equipped with a developing device for developing an electrostatic latent image formed on the outer peripheral surface of an image carrier, that is, for forming a toner image (developer image) by visualizing the electrostatic latent image.

[0003] The developing device includes a developing container that contains a developer including a toner, and a developer carrier that is arranged in contact with or in close proximity to an image carrier and carries the developer. The developing container has a container opening that opens on the downstream side of the developing container with respect to the direction of movement inside the image forming device when the developing device is attached to the image forming device. The developer carrier is arranged so as to overlap with the container opening. A part of the developer carrier is exposed to the outside of the developing device through this container opening. The developer carrier is capable of carrying toner in the developing container on its outer circumferential surface. The exposed part of the developer carrier from the container opening faces the image carrier, and a development area is formed that supplies toner in the developing container to the image carrier.

[0004] As such a developing device, Patent Document 1 discloses one in which a regulating blade is disposed upstream of the development area in the rotation direction of the developer carrier. The regulating blade protrudes toward the outer peripheral surface of the developer over the entire area along the direction of the rotation axis of the developer carrier. The tip of the regulating blade is in contact with or close to the outer peripheral surface of the developer carrier. The regulating blade regulates the layer thickness of the developer carried on the developer carrier.

[0005] The regulating blade is formed such that a fixed portion fixed to the developing container and a regulating portion that regulates the layer thickness of the developer on the developer carrier are formed as separate members, and are integrated by joining them by welding, adhesive, etc. In order to increase the rigidity and strength of the fixed portion, the regulating blade is made thicker than the regulating portion (see FIG. 5 of Patent Document 1). For this reason, a stepped shape is formed from the fixed portion to the regulating portion, and the distance from the fixed portion to the developing container is smaller than the distance from the regulating portion to the developing container.

[0006] In such a developing device, a blade seal member is disposed between the regulating blade and the developing container, and the blade seal member blocks the gap between the regulating blade and the developing container to prevent the developer from leaking out. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2015-11230 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, if the vertical length of the blade seal member is smaller than its thickness, the contact area between the regulating blade and the blade seal member is reduced, which may result in a decrease in sealing performance. If the pressing force of the regulating blade against the blade seal member is increased to increase the amount of compression of the blade seal member in order to improve the sealing performance of the blade seal member, the restoring force (reaction force) of the blade seal member also increases, making the regulating blade unstable. This may result in the regulating blade being slightly tilted, which may result in a decrease in sealing performance and make it easier for the developer to flow out.

[0009] Even if the blade seal member is disposed so as to contact the fixed portion and the regulating portion of the regulating blade in order to increase the contact area between the regulating blade and the blade seal member, the portion of the blade seal member between the regulating portion and the developing container is compressed less and has a smaller pressing force (restoring force) than the portion between the fixed portion and the developing container, which may cause a gap to form between the regulating portion and the blade seal member, causing the developer to leak out.

[0010] SUMMARY OF THE PRESENT EMBODIMENTS In view of the above, an object of the present invention is to provide a developing device capable of suppressing the outflow of developer. [Means for solving the problem]

[0011] In order to achieve the above object, a first configuration of the present invention is a developing device including a developing container, a developer carrier, and a regulating blade. The developing container has an opening and contains a developer including a toner inside. The developer carrier is rotatably supported by the developing container, and has a developing area where a part of the outer peripheral surface carrying the developer is exposed from the opening and faces the image carrier, and supplies toner to the image carrier in the developing area. The regulating blade is disposed upstream of the developing area in the rotation direction of the developer carrier, and regulates the layer thickness of the developer carried by the developer carrier. The developing container has a blade opposing portion that faces the surface of the regulating blade on the upstream side in the rotation direction. The developing device is provided with a blade seal member that is disposed between the regulating blade and the blade opposing portion and closes the gap between the regulating blade and the blade opposing portion. The regulating blade has a fixed portion that faces the blade opposing portion and is fixed to the developing container, and a regulating portion that protrudes from the fixed portion toward the developer carrier, and the distance between the regulating portion and the blade opposing portion is larger than the distance between the fixed portion and the blade opposing portion. The blade seal member is laminated on the upstream surface of the regulating portion in the rotational direction and the upstream surface of the fixed portion in the rotational direction, and is adhered to the upstream surface of the regulating portion in the rotational direction. Effect of the Invention

[0012] According to the first configuration of the present invention, the blade seal member is bonded to the regulating portion. Therefore, even if the regulating blade is slightly tilted, a gap is unlikely to occur between the blade seal member and the regulating blade, and outflow of developer can be suppressed. Even if the restoring force at the contact point with the regulating portion is relatively small, a gap is unlikely to occur between the seal member and the regulating portion. As a result, developer is unlikely to flow out of the developing container.

[0013] Therefore, it is possible to provide a developing device capable of suppressing the outflow of developer. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a side cross-sectional view showing a schematic configuration of an image forming apparatus 1 according to the present invention. [Diagram 2] FIG. 3 is a perspective view showing the entire developing device 33. [Diagram 3] FIG. 2 is an enlarged cross-sectional view of the photoconductor drum 31 and the peripheral portion of the developing device 33. [Figure 4] FIG. 2 is a plan view showing the developing device 33 in a state where the developing roller 37 (see FIG. 2), the regulating blade 64 (see FIG. 2), and the bush cover 63 (see FIG. 2) are removed from the developing container 36. [Diagram 5] 5 is a side cross-sectional view of the developing device 33 taken along the line AA in FIG. [Figure 6] FIG. 1 is a perspective view showing a blade seal member 67. [Figure 7] 5 is a partially enlarged view of the end portion of the blade seal member 67 of the developing device 33 (the area surrounded by the two-dot chain circle B in FIG. 4 ). [Figure 8] FIG. 4 is a partially enlarged cross-sectional view of the periphery of the regulating blade 64 (the area surrounded by the two-dot chain circle C in FIG. 3). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a side cross-sectional view showing a schematic configuration of an image forming apparatus 1 of the present invention. In Fig. 1, the right side of the figure is the front side of the image forming apparatus 1, and the left side of the figure is the rear side of the image forming apparatus 1. In Fig. 1, the upper side of the figure is the upper side of the image forming apparatus 1, and the lower side of the figure is the lower side of the image forming apparatus 1.

[0016] As shown in Fig. 1, the image forming apparatus 1 (here, a monochrome printer) includes a main housing 10 (apparatus main body) having a substantially rectangular parallelepiped casing structure, and a paper feed section 20, an image forming section 30, a developing device 33, and a fixing section 40 housed within the main housing 10. A front cover 11 is provided on the front side of the main housing 10, and a rear cover 12 is provided on the rear side. A main body opening 15 is provided above the main housing 10, and an upper cover 16 is provided on the top surface of the main housing 10 so that the main body opening 15 can be opened and closed. By opening the upper cover 16, the inside of the main housing 10 can be accessed through the main body opening 15.

[0017] A paper discharge section 13 is provided on the top surface of the upper cover 16, where sheets (recording media) after image formation are discharged. In the following description, the term "sheet" refers to copy paper, coated paper, overhead projector sheets, cardboard, postcards, tracing paper, and other sheet materials that undergo image formation processing.

[0018] The developing device 33 can be taken out and inserted through the main body opening 15 by opening the upper cover 16. The image forming section 30 and the fixing section 40 units (except the developing device 33) can be taken out and inserted through the rear side of the main body housing 10 by opening the rear cover 12.

[0019] The paper feed section 20 includes a paper feed cassette 21 that stores sheets on which an image forming process is performed. A part of the paper feed cassette 21 protrudes further forward from the front surface of the main body housing 10. The upper surface of the part of the paper feed cassette 21 that is stored in the main body housing 10 is covered by a paper feed cassette top plate 21U. The paper feed cassette 21 is provided with a paper storage space that stores a stack of sheets, a lift plate that lifts up the stack of sheets for feeding, and the like. A paper feed section 21A is provided at the upper part of the rear end side of the paper feed cassette 21. A paper feed roller 21B is arranged in the paper feed section 21A to feed the topmost sheet of the stack of sheets in the paper feed cassette 21 one by one.

[0020] Image forming unit 30 performs an image forming operation to form a toner image (developer image) on a sheet sent out from paper feed unit 20. Image forming unit 30 includes a photoconductor drum 31, and a charging unit 32, an exposure unit 35, a developing device 33, and a transfer roller 34, which are arranged around the photoconductor drum 31. The developer used for image formation is a non-magnetic one-component developer consisting only of toner.

[0021] The photoconductor drum 31 (image carrier) has a rotating shaft and an outer peripheral surface that rotates around the rotating shaft. The outer peripheral surface of the photoconductor drum 31 is made of, for example, a known organic (OPC) photoconductor, and a photosensitive layer made of a charge generation layer, a charge transport layer, etc. is formed on the outer peripheral surface. The photosensitive layer is uniformly charged by a charging unit 32 (described later), and then irradiated with light by an exposure unit 35 to form an electrostatic latent image in which the charge is attenuated, and a toner image in which the electrostatic latent image is visualized by a developing device 33 is carried on the photoconductor drum 31.

[0022] The charging section 32 (charging device) is disposed at a predetermined interval from the outer peripheral surface of the photosensitive drum 31, and uniformly charges the outer peripheral surface of the photosensitive drum 31 in a non-contact state. Specifically, the charging section 32 has a charge wire 321 and a grid electrode 322 (see FIG. 3 for both). The charge wire 321 is a linear electrode extending in the direction of the rotation axis of the photosensitive drum 31, and generates a corona discharge between the charge wire 321 and the photosensitive drum 31. The grid electrode 322 is a lattice-shaped electrode extending in the direction of the rotation axis of the photosensitive drum 31, and is disposed between the charge wire 321 and the photosensitive drum 31. The charging section 32 generates a corona discharge by passing a current of a predetermined current value through the charge wire 321, and applies a predetermined voltage to the grid electrode 322, thereby uniformly charging the outer peripheral surface of the photosensitive drum 31 facing the grid electrode 322 to a predetermined surface potential.

[0023] Exposure section 35 (exposure device) has a laser light source and optical devices such as mirrors and lenses, and irradiates the outer peripheral surface of photoconductor drum 31 with light modulated based on image data provided from an external device such as a personal computer. In this way, exposure section 35 forms an electrostatic latent image on the outer peripheral surface of photoconductor drum 31 that corresponds to an image based on the image data.

[0024] The transfer roller 34 has a rotation axis parallel to the width direction of the sheet and an outer circumferential surface facing the outer circumferential surface of the photoreceptor drum 31, and is supported by the main housing 10 so as to be rotatable about the rotation axis. The transfer roller 34 transfers the toner image carried on the outer circumferential surface of the photoreceptor drum 31 to the sheet passing through a nip portion between the transfer roller 34 and the outer circumferential surface of the photoreceptor drum 31. During transfer, a transfer voltage of opposite polarity to that of the toner is applied to the transfer roller 34.

[0025] The fixing unit 40 is located downstream of the transfer roller 34 in the sheet conveying direction, and fixes the toner image transferred to the sheet onto the sheet. The fixing unit 40 has a fixing roller 41 and a pressure roller 42. The fixing roller 41 has an internal heating source and heats the toner transferred to the sheet to a predetermined temperature. The pressure roller 42 is pressed against the fixing roller 41, forming a fixing nip between the fixing roller 41 and the pressure roller 42. When the sheet onto which the toner image has been transferred is passed through the fixing nip, the toner image is fixed onto the sheet by the heating by the fixing roller 41 and the pressure by the pressure roller 42.

[0026] A main transport path 22F and a reverse transport path 22B for transporting a sheet are provided inside the main housing 10. The main transport path 22F extends from the paper feed section 21A of the paper feed section 20, via the image forming section 30 and the fixing section 40, to the paper discharge port 14 provided opposite the paper discharge section 13 on the upper surface of the main housing 10. The reverse transport path 22B is a transport path for returning a sheet that has been printed on one side to the upstream side of the image forming section 30 on the main transport path 22F when double-sided printing is performed on the sheet.

[0027] The main transport path 22F extends from below to above the transfer nip formed by the photoconductor drum 31 and the transfer roller 34. A pair of registration rollers 23 is disposed upstream of the transfer nip on the main transport path 22F. The sheet is temporarily stopped by the pair of registration rollers 23, and after skew correction, the sheet is sent to the transfer nip at a predetermined timing for image transfer. A plurality of transport rollers for transporting the sheet are disposed at appropriate positions on the main transport path 22F and the reverse transport path 22B. A pair of paper discharge rollers 24 is disposed near the paper discharge port 14.

[0028] The reverse conveying path 22B is formed between the outer surface of the reversing unit 25 and the inner surface of the rear cover 12 of the main housing 10. The transfer roller 34 and one of the pair of registration rollers 23 are mounted on the inner surface of the reversing unit 25. The rear cover 12 and the reversing unit 25 are each rotatable about a fulcrum 121 provided at the lower end thereof. When a jam (paper jam) occurs in the reverse conveying path 22B, the rear cover 12 is opened. When a jam occurs in the main conveying path 22F, or when the unit of the photosensitive drum 31 or the developing device 33 is taken out to the outside, the reversing unit 25 is also opened in addition to the rear cover 12.

[0029] As shown in Fig. 1, guide rails 18 are formed on a pair of side surfaces 17 facing each other in the sheet width direction (the paper surface direction of Fig. 1) inside the main body housing 10. The guide rails 18 have a rail structure recessed in the sheet width direction. The guide rails 18 extend downward from the main body opening 15 to a mounting position P1 of the developing device 33 relative to the main body housing 10.

[0030] Fig. 2 is a perspective view showing the entire developing device 33. Fig. 3 is an enlarged cross-sectional view showing the photosensitive drum 31 and the peripheral portion of the developing device 33. Fig. 4 is a plan view showing the developing device 33 in a state where the developing roller 37 (see Fig. 2), the regulating blade 64 (see Fig. 2), and the bush cover 63 (see Fig. 2) are removed from the developing container 36.

[0031] As shown in FIGS. 2, 3, and 4, the developing device 33 includes a developing container 36, a developing roller 37 (developer carrier), a supply roller 38, an agitating paddle 333, and a guide portion 69.

[0032] The developing container 36 has a stirring chamber 335 that contains the developer in a stirred state, a container opening 60 (opening) located rearward of the stirring chamber 335 in the front-to-rear direction, and bush covers 63 that are removably attached to both ends of the developing container 36 in the sheet width direction, and contains a non-magnetic single-component developer consisting only of toner inside, as well as the developing roller 37, the supply roller 38, etc.

[0033] The container opening 60 is a rectangular through-hole that opens to the rear side (the side closer to the photoconductor drum 31) of the developing container 36. The container opening 60 is formed to be elongated in the width direction (axial direction) of the developing device 33.

[0034] The developing roller 37 is provided inside the container opening 60 so as to overlap the container opening 60. A part of the outer peripheral surface of the developing roller 37 is exposed to the outside of the developing container 36 from the container opening 60. The developing roller 37 has a rotation shaft 39 extending along the width direction (width direction of the sheet) of the developing device 33. The rotation shaft 39 is supported by the developing container 36 so as to be rotatable about the rotation shaft 39. In other words, the developing roller 37 is supported by the developing container 36 via the rotation shaft 39 so as to be rotatable clockwise as shown in the figure (see FIG. 3 ). Hereinafter, the direction along the rotation shaft 39 is referred to as the "axial direction". The rotation direction of the developing roller 37 around the rotation shaft 39 is referred to as the "rotation direction".

[0035] The developing roller 37 can carry toner on its outer circumferential surface. When the developing device 33 is in the mounting position P1, the portion of the developing roller 37 exposed from the container opening 60 is in contact with or closely faces the outer circumferential surface of the photosensitive drum 31. In this state, the developing roller 37 can supply non-magnetic single-component toner (developer) to the photosensitive drum 31.

[0036] Supply roller 38 is provided between developing roller 37 and stirring paddle 333, and supplies non-magnetic one-component toner (developer) to the outer circumferential surface of developing roller 37. Stirring paddle 333 is provided in stirring chamber 335, and stirs the developer inside stirring chamber 335.

[0037] The bush covers 63 are detachably provided at both axial ends of the developing container 36, and constitute side walls of the developing container 36. The bush covers 63 are formed with a plurality of through holes penetrating in the axial direction, and the rotation shaft of the developing roller 37 and the rotation shaft of the supply roller 38 are inserted into these through holes to rotatably support the developing roller 37 and the supply roller 38.

[0038] The guide portion 69 is a cylindrical protrusion protruding from the bush cover 63. (The guide portion 69 is engageable with the guide rail 18. The developing device 33 is movable along the guide rail 18 between the main body opening 15 and the mounting position P1 by engaging the guide portion 69 with the guide rail 18.

[0039] The developing device 33 mounted in the main housing 10 at the mounting position P1 supplies toner to the outer peripheral surface of the photoconductor drum 31. This develops the electrostatic latent image formed on the outer peripheral surface of the photoconductor drum 31 (forming a toner image (visible image) that visualizes the electrostatic latent image).

[0040] As shown in Figures 2 and 4, around the container opening 60, there are provided a pressing member 43 provided at both axial ends of the developing roller 37, a flat portion 62 located rearward of the container opening 60 (the side closer to the photosensitive drum 31), a front seal member 65 provided on the flat portion 62, a regulating blade 64 fixed to the rear end of the developing container 36, and a blade seal member 67 laminated on the back side of the regulating blade 64.

[0041] Fig. 5 is a side cross-sectional view of the developing device 33 taken along the AA cross-sectional line shown in Fig. 4. Fig. 6 is a perspective view showing the blade seal member 67. Fig. 7 is a partial enlarged view showing the periphery of the end portion of the blade seal member 67 of the developing device 33 (the area surrounded by the two-dot chain circle B in Fig. 4). Note that the blade seal member 67 shown in Fig. 6 is shown in a state in which the blade seal member 67 shown in Fig. 4 is inverted in the front-to-rear direction, and the left-to-right direction is reversed between Figs. 4 and 6.

[0042] The pressing members 43 are disposed on both axial ends of the container opening 60 (see FIG. 2). As shown in FIG. 5, the pressing member 43 has a pressing surface 44 that is curved to be recessed toward the front side (the stirring chamber 335 side) along the outer peripheral surface of the developing roller 37. The pressing surface 44 faces the outer peripheral surfaces of both end portions 66 of the developing roller 37 in the radial direction of the developing roller 37. The thickness of the pressing member 43 is formed to be larger than the gap between the outer peripheral surface of the developing roller 37 and the inner surface of the developing container 36. As a result, when the developing roller 37 is attached to the developing container 36, the pressing surface 44 comes into contact with the outer peripheral surface of the developing roller 37 and presses the developing roller 37 in the radial direction. The pressing surface 44 comes into contact with and presses the both end portions 66, thereby closing the gap between the both end portions 66 and the developing container 36 and suppressing the developer from flowing out from inside the developing container 36.

[0043] The pressing member 43 has a multi-layer structure (here, a two-layer structure) in which a plurality of sheet bodies are stacked in the radial direction of the developing roller 37. Of these multi-layer sheets, at least the sheet body closest to the developing roller 37 in the radial direction is a polytetrafluoroethylene (so-called Teflon (registered trademark)) sheet body. The pressing surface 44 is formed on the surface of this sheet body. The other sheet bodies of the multi-layer sheet body are formed of urethane foam such as sponge.

[0044] 2 and 3, the flat portion 62 located around the container opening 60 is a flat surface that is connected to a portion of the inner surface of the developer container 36 that is located below the developing roller 37. The flat portion 62 extends rearward (toward the photoconductor drum 31) from the container opening 60. When the developing device 33 is in the mounting position P1, the flat portion 62 is approximately horizontal.

[0045] The front seal member 65 is a rectangular sheet made of a PET film or the like. The front seal member 65 is laminated on the flat portion 62 and adhered to the developing container 36 with an adhesive or the like. The front seal member 65 is formed to be elongated in the axial direction. The front seal member 65 extends between both end portions 66 of the developing roller 37 along the axial direction.

[0046] Of both ends of the front and rear direction (direction perpendicular to the sheet width direction) of the front seal member 65, the end edge closer to the developing roller 37 (supply roller 38) is in contact with the entire developer-carrying area of ​​the outer circumferential surface of the developing roller 37 in the axial direction. The front seal member 65 closes the gap between the developing container 36 and the developing roller 37 by contacting the outer circumferential surface of the developing roller 37, thereby preventing the developer in the developing container 36 from flowing out.

[0047] The front seal member 65 has a first shielding portion 19 that rises in the surface direction of the front seal member 65 from the edge farther from the developing roller 37 (supply roller 38) of both end edges in the front-rear direction (direction perpendicular to the sheet width direction). The first shielding portion 19 protrudes upward over the entire axial area of ​​the edge of the front seal member 65. The first shielding portion 19 has a rectangular shape formed from a sponge or the like, and is adhered to the surface of the front seal member 65 with an adhesive or the like. The first shielding portion 19 holds the developer that flows out slightly from the gap between the developing roller 37 and the developing container 36 so that it does not fall outside the developing device 33.

[0048] On the outer sides of both axial ends of the first shielding portion 19, plate-shaped second shielding portions 53 protruding upward are provided. The second shielding portions 53 are located at positions overlapping with the pressing members 43 in the axial direction. The second shielding portions 53 are formed integrally with the bush cover 63. When the bush cover 63 is attached to the developing container 36, the second shielding portions 53 extend from the bush cover 63 along the axial direction so as to approach the first shielding portions 19.

[0049] FIG. 8 is a partially enlarged view showing a cross section of the periphery of the regulating blade 64 (the area surrounded by a two-dot chain circle C in FIG. 3).

[0050] 8, the developing container 36 has a blade facing portion 45 at an upper portion of the opening edge of the container opening 60, the blade facing portion 45 facing the upstream surface in the rotation direction of the regulating blade 64 (the front surface in the front-rear direction). The blade facing portion 45 is formed flat in the axial direction.

[0051] The regulating blade 64 is a rectangular plate-like body formed to be elongated in the axial direction (see FIG. 2). The regulating blade 64 is composed of a fixed portion 46 and a regulating portion 47. The fixed portion 46 is a metal plate-like body that is L-shaped in a side view and has a bent portion that is bent at a substantially right angle. The fixed portion 46 is disposed so as to face the blade facing portion 45 in the rotational direction.

[0052] The regulating portion 47 is a rectangular metal plate-like body that is elongated in the axial direction. The upper end of the regulating portion 47 is laminated and welded to the surface of the fixed portion 46 on the downstream side in the rotation direction (the photoconductor drum 31 side). The regulating portion 47 protrudes from the lower end of the fixed portion 46 (the end of the fixed portion 46 that is closest to the developing roller 37 in the vertical direction) toward the developing roller 37.

[0053] The tip of the regulating portion 47 in the protruding direction is disposed in contact with the outer circumferential surface of the developing roller 37. The toner supplied onto the developing roller 37 enters between the regulating portion 47 and the developing roller 37 as the developing roller 37 rotates, and is then supported on the developing roller 37 as a thin layer of a certain thickness while being further triboelectrically charged.

[0054] 8, the thickness of the restricting portion 47 (the dimension in the front-rear direction in FIG. 8) is thinner than the thickness of the fixed portion 46. In other words, the distance L2 between the restricting portion 47 and the blade opposing portion 45 in the thickness direction is larger than the distance L1 between the fixed portion 46 and the blade opposing portion 45 in the thickness direction.

[0055] At the location of the regulating blade 64 where the fixing portion 46 and the regulating portion 47 are laminated, a through hole penetrating the fixing portion 46 and the regulating portion 47 is formed in the surface direction (thickness direction) of the fixing portion 46. The fixing portion 46 is fixed to the blade opposing portion 45 by a fastening member 48 consisting of a bolt inserted into the through hole and a nut.

[0056] 8, a blade seal member 67 is provided between the regulating blade 64 and the developing container 36 in the rotation direction (direction perpendicular to the axial direction). The blade seal member 67 is disposed between a pair of pressing members 43 in the axial direction (see FIG. 4). The blade seal member 67 is made of a multi-layer sheet including a first laminate material 70 and a second laminate material 71 laminated in the front-rear direction.

[0057] The first laminated material 70 is formed in a rectangular shape by sponge such as Poron. The first laminated material 70 is formed long and thin in the axial direction. Both axial end portions of the first laminated material 70 are pressed (contacted and pressed) against the pressing members 43 (see FIG. 4). The first laminated material 70 is laminated on the surfaces of the fixing portion 46 and the regulating portion 47 that are farther from the photosensitive drum 31 (upstream surfaces in the rotation direction of the developing roller 37). A double-sided tape having an adhesive component on both sides is attached to the surface of the first laminated material 70 on the downstream side in the rotation direction (rear side in the front-rear direction). In other words, a double-sided tape is arranged between the first laminated material 70 and the regulating portion 47. The first laminated material 70 is adhered to the regulating portion 47 by this double-sided tape.

[0058] The first laminated material 70 is pressed and compressed toward the blade opposing portion 45 by the fixing portion 46 and the restricting portion 47. The amount of compression of the portion of the first laminated material 70 between the fixing portion 46 and the blade opposing portion 45 is greater than the amount of compression of the portion of the first laminated material 70 between the restricting portion 47 and the blade opposing portion 45.

[0059] The first laminated material 70 is formed so that the dimension in the up-down direction is larger than the dimension in the thickness direction (front-rear direction) before (before compression) and after (after compression) it is placed between the regulating blade 64 and the blade opposing portion 45. In other words, the cross section orthogonal to the axial direction of the first laminated material 70 is elongated in the up-down direction.

[0060] 4 and 6, the first laminated material 70 is composed of a first seal member 72 and a second seal member 73, which are arranged in the axial direction. A connecting portion 74 is formed at the opposing portion between the first seal member 72 and the second seal member 73.

[0061] The first seal member 72 has a first protruding portion 75 and a first recessed portion 76 formed at an end portion located toward the center of the container opening 60 in the axial direction. The first protruding portion 75 protrudes in the axial direction from the end portion of the first seal member 72. The first recessed portion 76 is recessed from the tip of the first protruding portion 75 in the protruding direction in the opposite direction to the protruding direction. The first protruding portion 75 and the first recessed portion 76 are adjacent to each other in a direction perpendicular to the axial direction.

[0062] The second seal member 73 has a second protruding portion 77 and a second recessed portion 78 formed at an end portion located toward the center of the container opening 60 in the axial direction. The second protruding portion 77 protrudes in the axial direction from the end portion of the second seal member 73. The second recessed portion 78 is recessed from the tip of the second protruding portion 77 in the protruding direction in the opposite direction to the protruding direction. The second protruding portion 77 and the second recessed portion 78 are adjacent to each other in a direction perpendicular to the axial direction.

[0063] The second protruding portion 77 overlaps with the first recess 76 in a direction perpendicular to the axial direction (the up-down direction). The length from the bottom of the second recess 78 to the tip of the second protruding portion 77 is equal to or slightly smaller than the length from the bottom of the first recess 76 to the tip of the first protruding portion 75. The first protruding portion 75 is inserted into the second recess 78, and the second protruding portion 77 is inserted into the first recess 76.

[0064] The connecting portion 74 is composed of a first protruding portion 75, a first recess 76, a second protruding portion 77, and a second recess 78, and axially joins the first sealing member 72 and the second sealing member 73 with adhesive applied so as to seal the space between the first protruding portion 75 and the second recess 78, and between the first recess 76 and the second protruding portion 77.

[0065] The second laminate material 71 is an axially elongated sheet material made of polyethylene terephthalate (PET). The second laminate material 71 has greater rigidity than the first laminate material 70. As shown in FIGS. 5 and 6, the second laminate material 71 is laminated on the surface of the first laminate material 70 opposite to the surface that comes into contact with the regulating blade 64 (the surface farther from the developing roller 37 in the front-rear direction), and is adhered thereto with an adhesive or the like. One second laminate material 71 is laminated on each of the first seal member 72 and the second seal member 73.

[0066] The axial length of the second laminate material 71 is shorter than the axial length of the blade seal member 67. Both end portions of the second laminate material 71 are located more inward than both end portions of the blade seal member 67 in the axial direction. In the regions extending from both axial end portions of the blade seal member 67 to both end portions of the second laminate material 71, cushion portions 68 are formed in which the first laminate material 70 protrudes from the second laminate material 71.

[0067] The second laminated material 71 is provided with seal-side positioning protrusions 79 (positioning protrusions) at positions symmetrical about the axial direction and inward from both ends of the second laminated material 71. The seal-side positioning protrusions 79 protrude outward in the axial direction and in the up-down direction beyond the edges of the blade seal member 67 (see FIG. 7).

[0068] 4 and 7, container side positioning protrusions 80 are formed on both axial ends of the container opening 60, protruding downward from a part of the inside of the developing container 36. An opposing surface 81 is formed on a surface of the container side positioning protrusion 80 that is closer to the center of the container opening 60 in the axial direction. The opposing surfaces 81 of the container side positioning protrusions 80 face each other in the axial direction, with a part of the blade seal member 67 sandwiched therebetween.

[0069] The seal side positioning protrusions 79 are located inside each container side positioning protrusion 80 in the axial direction. The seal side positioning protrusions 79 and the container side positioning protrusions 80 are positioned so as to overlap in the up-down direction. The seal side positioning protrusions 79 face the container side positioning protrusions 80 in the axial direction. The seal side positioning protrusions 79 come into contact with the container side positioning protrusions 80, thereby positioning the second laminate material 71 in the axial direction.

[0070] As described above, the first laminated material 70 is adhered to the regulating portion 47. Therefore, even if the regulating blade 64 is slightly tilted, a gap is unlikely to occur between the regulating portion 47 and the first laminated material 70, and outflow of the developer can be suppressed.

[0071] As described above, the compression amount of the first laminated material 70 at the location between the fixed portion 46 and the blade facing portion 45 is greater than the compression amount of the first laminated material 70 at the location between the regulating portion 47 and the blade facing portion 45. That is, the restoring force of the first laminated material 70 at the location between the regulating portion 47 and the blade facing portion 45 is smaller than the restoring force of the first laminated material 70 at the location between the fixed portion 46 and the blade facing portion 45. However, since the first laminated material 70 is bonded to the regulating portion 47, a gap is unlikely to occur between the first laminated material 70 and the regulating portion 47. As a result, the developer is unlikely to flow out of the developing container 36.

[0072] Therefore, it is possible to provide a developing device 33 capable of appropriately regulating the layer thickness of the developer on the developing roller 37 and suppressing the outflow of the developer.

[0073] The first laminated material 70 is formed so that the dimension in the vertical direction of the first laminated material 70 in the compressed state is larger than the dimension in the thickness direction, and is laminated on the fixing portion 46 and the regulating portion 47. That is, the first laminated material 70 comes into contact with the regulating blade 64 over a relatively wide range in the vertical direction. Then, the pressing force of the regulating blade 64 against the blade facing portion 45 can be suppressed to a level at which the regulating blade 64 is stable, and the inclination of the regulating blade 64 can be suppressed. Therefore, the outflow of the developer can be more suitably suppressed, and a situation in which the regulating blade 64 is inclined and the layer thickness of the developer on the developing roller 37 cannot be appropriately regulated can be avoided.

[0074] As described above, the rigidity of the second laminated material 71 is greater than the rigidity of the first laminated material 70. Therefore, when the second laminated material 71 is bonded to the first laminated material 70, the second laminated material 71 is less likely to wrinkle or fold, and a gap is less likely to occur between the second laminated material 71 and the developing container 36 (the blade facing portion 45).

[0075] Furthermore, since the second laminated material 71, which has a relatively high rigidity, is laminated and bonded to the first laminated material 70, the first laminated material 70 is supported by the second laminated material 71 and is less likely to bend. Therefore, when the first laminated material 70 is bonded to the regulating blade 64 (the fixing portion 46 and the regulating portion 47), it is possible to prevent the adhesion surface of the first laminated material 70 to the regulating portion 47 from wrinkling or bending. Therefore, a gap is less likely to occur between the first laminated material 70 and the regulating portion 47, and outflow of the developer can be more suitably prevented.

[0076] As described above, the second laminate 71 is positioned by contact between the seal side positioning protrusion 79 and the opposing surface 81. Since the second laminate 71 has a higher rigidity than the first laminate 70, the blade seal member 67 can be easily positioned by contact between the seal side positioning protrusion 79 and the opposing surface 81. Here, the second laminate 71 is laminated and bonded to the first laminate 70, and the first laminate 70, i.e., the blade seal member 67, is positioned by positioning the second laminate 71. In this state, the first laminate 70 is pressed against the pressing member 43, and therefore the gap in the axial direction between the developing container 36 and the blade seal member 67 is blocked via the pressing member 43, and the developer outflow path can be blocked.

[0077] As described above, both ends of the second laminated material 71 are located axially inward of both ends of the first laminated material 70, and cushion portions 68 are formed in the portions of the first laminated material 70 extending from both ends of the second laminated material 71 to both ends of the first laminated material 70. Therefore, when the blade seal member 67 is positioned and both ends of the first laminated material 70 contact the pressing member 43, the cushion portions 68 are compressed. Then, the compression ratio of the portions (cushion portions 68) of the first laminated material 70 that contact the pressing member 43 increases, and the sealing performance between the first laminated material 70 and the pressing member 43 can be improved. Therefore, the outflow of the developer can be more suitably suppressed.

[0078] As described above, the first laminate 70 connects the first seal member 72 and the second seal member 73, which are formed separately, by the connecting portion 74. The second laminate 71 is laminated on each of the first seal member 72 and the second seal member 73. Therefore, when the blade seal member 67 is disposed between the pair of pressing members 43 in the axial direction, it can be disposed with a backlash (gaps) between each pressing member 43 and the first seal member 72 and the second seal member 73. In this state, it becomes possible to bond the first seal member 72 and the second seal member 73 with an adhesive at a distance such that a predetermined contact pressure is generated between the blade seal member 67 and the pressing member 43. This improves the ease of assembly and reduces the manufacturing cost of the developing device 33.

[0079] Furthermore, a first shielding portion 19 is provided that protrudes upward over the entire longitudinal edge of the front seal member 65. Therefore, even if waste toner has accumulated around the container opening 60, when the developing device 33 faces downward when attached to the main housing 10, the waste toner around the container opening 60 is blocked by the first shielding portion 19. This makes it possible to prevent the waste toner from falling into the main housing 10.

[0080] Therefore, it is possible to provide a developing device 33 that can prevent developer from leaking out from the gap between the developing roller 37 and the developing container 36, while preventing developer from falling into the inside of the main housing 10 from around the container opening 60 of the developing device 33.

[0081] As described above, the second shielding portion 53 is located at a position overlapping with the pressing member 43 in the axial direction. Therefore, even if a small amount of developer flows out from the gap between the pressing member 43 and the developing roller 37, the second shielding portion 53 prevents the developer from flowing out to the outside of the developing container 36. As described above, the second shielding portion 53 is formed integrally with the bush cover 63. Therefore, when the bush cover 63 is attached, the second shielding portion 53 is also positioned at a predetermined position. This reduces the number of assembly steps and suppresses manufacturing costs.

[0082] In addition, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the spirit of the present invention. For example, in the above embodiment, a monochrome printer is described as an example of the image forming apparatus 1, but the present invention can also be applied to, for example, a tandem type or rotary type color printer. The present invention can also be applied to image forming apparatuses such as copiers, facsimiles, or multifunction machines equipped with these functions.

[0083] As described above, the first laminated material 70 is adhered to the restricting portion 47, but in addition, it may be adhered to the fixing portion 46 as well.

[0084] Moreover, the blade seal member 67 may be configured to include only the first laminate material 70 without including the second laminate material 71. In this case, a configuration may be adopted in which the surface of the first laminate material 70 opposite the blade seal member 67 is bonded to the blade opposing portion 45.

[0085] In the above embodiment, the first shielding portion 19 is formed from a sponge, but the present invention is not limited to this and may be formed from other materials. The first shielding portion 19 may be formed integrally with the front seal member 65 and bent so as to rise upward from the edge of the front seal member 65. In this case, the number of parts of the front seal member 65 is reduced, and manufacturing costs can be reduced.

[0086] In the above embodiment, the developer is a non-magnetic one-component developer made of only toner, but a two-component developer using toner and a carrier can also be used. [Industrial Applicability]

[0087] The present invention can be applied to an image forming apparatus including a developing device that performs development using a developer containing a toner. By using the present invention, it is possible to provide an image forming apparatus that can suppress the outflow of the developer. [Explanation of symbols]

[0088] 1. Image forming device 10 Main body housing (device main body) 31 Photoconductor drum (image carrier) 33 Developing device 36 Developer container 37 Developing roller (developer carrier) 39 Rotational Axis 45 Blade opposing part 46 Fixed part 47 Regulatory Department 60 Container opening (opening) 64 Regulatory Blade 67 Blade seal material 70 First laminate 71 Second laminate 72 First seal member 73 Second seal member 74 Connecting part 75 1st protrusion 76 First recess 77 Second protrusion L1 Distance between the fixed part and the blade facing part L2 Distance between the restricting part and the blade opposing part P1 Installation position

Claims

1. a developer container having an opening and accommodating a developer including a toner therein; a developer carrier that is rotatably supported by the developing container, has a development area in which a part of an outer peripheral surface that carries the developer is exposed through the opening and faces an image carrier, and supplies the toner to the image carrier in the development area; a regulating blade disposed upstream of the developing region in a rotation direction of the developer carrier and regulating a layer thickness of the developer carried by the developer carrier; In a developing device comprising: the developing container has a blade facing portion facing an upstream surface of the regulating blade in the rotation direction, a blade seal member disposed between the regulating blade and the blade opposing portion and configured to close a gap between the regulating blade and the blade opposing portion; the regulating blade has a fixed portion that faces the blade opposing portion and is fixed to the developing container, and a regulating portion that protrudes from the fixed portion toward the developer carrier, and a distance between the regulating portion and the blade opposing portion is larger than a distance between the fixed portion and the blade opposing portion, The blade seal member is bonded to a surface of the regulating portion on an upstream side in the rotation direction, The blade seal member is a first laminated material laminated on a surface facing the regulating blade; A second laminated material having a rigidity greater than that of the first laminated material and laminated on a surface of the first laminated material opposite to the regulating blade; having A developing device, characterized in that both end portions of the second laminate along the rotational axis direction of the developer carrier are located more inward than both end portions of the first laminate along the rotational axis direction.

2. The present invention further comprises a pair of pressing members contacting an outer peripheral surface of the developer carrier at both ends of the developer carrier in the direction of the rotation axis and closing a gap between the both ends of the developer carrier and the developing container, The first laminated material has cushion portions protruding from both ends of the second laminated material to both ends of the first laminated material in the rotation axis direction, 2. The developing device according to claim 1, wherein the cushion portion is pressed against the pressing member in the direction of the rotation axis to close a gap between the pressing member and the blade seal member.

3. 3. The developing device according to claim 1, wherein the surface of the second laminate on the upstream side in the rotational direction is bonded to the blade opposing portion.

4. the first laminated material includes a first seal member and a second seal member aligned in the rotation axis direction, and a connecting portion formed at an opposing portion of the first seal member and the second seal member, The connecting portion is a first protruding portion protruding in the rotation axis direction from an end portion of the first seal member on the second seal member side in the rotation axis direction toward the second seal member; a first recess recessed from the end of the first seal member in a direction opposite to a protruding direction of the first protruding portion; a second protruding portion protruding in the rotation axis direction from an end portion of the second seal member on the first seal member side in the rotation axis direction and inserted into the first recess; a second recess that is recessed from the end of the second seal member in a direction opposite to a protruding direction of the second protruding portion and into which the first protruding portion is inserted; having 4. A developing device according to claim 1, wherein the first seal member and the second seal member are adhered to each other by applying an adhesive to at least a portion between the first protruding portion and the second recess and between the first recess and the second protruding portion, and the adhesive seals a gap between the first seal member and the second seal member.

5. 5. The developing device according to claim 1, wherein the first laminated material is a sponge.

6. 6. The developing device according to claim 1, wherein the second laminated material is a sheet material made of polyethylene terephthalate.

7. A device body, the image carrier provided inside the apparatus body and having an outer circumferential surface on which an electrostatic latent image is formed; 7. The developing device according to claim 1, which is detachably provided inside the main body of the apparatus, and in a state where the developing device is attached inside the main body of the apparatus, the developer carrier comes into contact with or is close to an outer circumferential surface of the image carrier to develop the electrostatic latent image into a toner image; An image forming apparatus comprising:

Images