JP5218141B2 - Developing device, developing cartridge, process cartridge, and image forming apparatus - Google Patents

Description

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

  As an electrophotographic image forming apparatus such as a laser printer, a process cartridge comprising a drum cartridge having a photosensitive drum as an image carrier and a developing cartridge as a developing device detachable from the drum cartridge is included in the main body On the other hand, what was provided so that attachment or detachment was possible is known.

  The developing cartridge includes a toner storage chamber that stores toner as a developer in a housing, and a development chamber that communicates with the toner storage chamber via a toner supply port. The toner is provided in the toner storage chamber. It is discharged into the developing chamber by the agitator. The developing chamber is provided with a supply roller, a developing roller as a developer carrying member, and the like, and toner in the developing chamber is supplied to the developing roller by the rotation of the supply roller. The toner supplied to the developing roller is leveled by a layer thickness regulating blade pressed against the surface of the developing roller, and a toner image is formed on the photosensitive drum by developing the toner on the photosensitive drum.

  This toner image is transferred to the conveyed paper, and then the toner image is fixed on the paper by a fixing device provided in the laser printer body, whereby the image forming operation is completed.

  This developing cartridge has a problem that toner leaks from the periphery of the rotating developing roller to the outside. In order to prevent toner leakage, conventionally, a toner leakage prevention member has been provided inside the housing of the developing cartridge (see Prior Art Document 1). For example, in order to prevent toner leakage from both ends of the developing roller, a toner leakage preventing member called a side seal is attached along the circumferential direction of the developing roller, and is rubbed against the peripheral surfaces of both ends of the developing roller. .

  The side seal has a structure in which a felt rubbing seal member is attached to urethane sponge. Urethane sponges are required to be sufficiently soft and have little compression set. The rubbing seal member is used for both ensuring the pressing force and reducing the rotational torque.

  Further, in order to prevent toner leakage from the gap between the developing roller formed above the developing roller and the opening of the housing, the rubber portion (rubber blade) of the layer thickness regulating blade is pressed against the developing roller. Thus, the layer thickness regulating blade has a function as a toner leakage preventing member.

Further, the rubbing seal member is adhered to the urethane sponge so as not to form a gap by being in close contact with both end faces of the rubber blade. That is, it is configured so that no toner is leaked between the both ends of the rubber blade and the rubbing seal member so as not to create a gap.

JP 2003-195630 A

  However, there are cases where an operator mistakes how to attach the rubbing seal member during the manufacturing process. That is, there is a case where the rubbing seal member is stuck obliquely with respect to the end face in an attempt to stick the rubbing seal member to the end face of the rubber blade. As a result, the adhesion between the rubber blade and the rubbing seal member is weakened and a gap may be formed. As a result, there is a problem that the toner leaks from the gap with the use of the image forming apparatus accompanied by the rotation of the developing roller.

  In view of the above problems, an object of the present invention is to provide a developing device, a developing cartridge, a process cartridge, and an image forming apparatus that can improve adhesion between a rubbing seal member and a layer thickness regulating member and prevent toner leakage. To do.

In order to solve the above-described problems, the developing device, the developing cartridge, the process cartridge, and the image forming apparatus of the present invention are rotatable on a housing that stores the developer and both side walls near the opening of the housing. The thickness of the developer on the developer carrier is regulated by a supported developer carrier and a contact surface that extends in the rotation axis direction of the developer carrier and contacts the peripheral surface of the developer carrier. A layer thickness regulating member that is slidably rubbed against the peripheral surfaces of both ends of the developer carrier in the vicinity of both side walls of the opening of the housing, and the longitudinal direction of the layer thickness regulating member A developing device that forms a visible image by causing a thin layer of the developer on the developer carrying member to face an electrostatic latent image, the seal member contacting each of both end surfaces in the direction. The longitudinal end surfaces of the regulating member are the lengths of the contact surface in the longitudinal direction. As but towards the upstream side is longer than the downstream in the rotational direction of the developer carrying member, the inclined surface is formed, the sealing member, the layer thickness regulating extend in a perpendicular direction perpendicular to the rotational axis A downstream portion pressed against the inclined surface of the member, and an upstream formed continuously from the downstream portion and upstream of the downstream portion in the rotation direction of the developer carrier. A boundary portion between the downstream portion and the upstream portion is located upstream of the upstream end in the rotation direction of the developer carrier on the contact surface of the layer thickness regulating member. The downstream portion extends in a direction perpendicular to the rotational axis direction from the upstream end in the rotation direction of the developer carrier on the contact surface of the layer thickness regulating member to the boundary portion, and the upstream portion Is the direction of rotation from the boundary Characterized in that it extends so as to face to the rotation axis direction outside with the orthogonal direction to an angle toward the upstream side.

  The seal member may be provided in pressure contact with the inclined surface.

  Further, the inclined surface is press-contacted so that the upstream side bites into at least the seal member.

  According to the developing device, the developing cartridge, the process cartridge, and the image forming apparatus of the present invention, the longitudinal length of both end surfaces of the layer thickness regulating member is longer than the downstream side in the rotation direction of the developer carrier. Since the inclined surface is formed so that the upstream side is longer, the seal member that comes into contact with the inclined surface is more likely to come into close contact with the inclined surface toward the upstream side. Therefore, the gap between the layer thickness regulating member and the seal member is less likely to be formed on the upstream side in the rotation direction of the developer carrier. This can prevent the developer on the developer carrying member from leaking between the seal member and the layer thickness regulating member.

  Further, since the seal member is provided in pressure contact with the inclined surface, there is no gap between the seal member and the layer thickness regulating member. Therefore, the developer on the developer carrying member can be prevented from leaking between the seal member and the layer thickness regulating member.

  Further, since the upstream side is in pressure contact with at least the seal member, the adhesiveness between the seal member and the layer thickness regulating member is increased toward the upstream side in the rotation direction of the developer carrier. As a result, the developer on the developer carrying member can be further prevented from leaking between the seal member and the layer thickness regulating member.

2 is a cross-sectional view of a main part of the laser printer 1. FIG. 3 is a cross-sectional view of a main part of the developing device 50. FIG. FIG. 6 is a perspective view of a principal part showing a seal structure of axial end portions of the developing roller 59 and the supply roller 58 of the developing device 50 (the developing roller 59 is not mounted), and the sponge seal member 65 of the side seal 33 is attached. In this state, the supply roller 58 is not attached. FIG. 4 is a cross-sectional side view of a main part showing a seal structure of an end portion in the axial direction of the developing roller 59 shown in FIG. 3, showing a state where the developing roller 59 is not mounted. FIG. 3 is a front view of main parts of axial end portions of a developing roller and a supply roller shown in FIG. 2. It is a principal part front view when a rubbing seal member is affixed on FIG. FIG. 6 is an enlarged view of the rubbing seal member and the rubber blade of FIG. 5. FIG. 3 is a perspective view of a principal part showing a seal structure of axial ends of a developing roller 59 and a supply roller 58 of the developing device 50 (the developing roller 59 is not attached). It is a principal part front view which shows the seal structure of the axial direction edge part of the developing roller as other embodiment. FIG. 10 is an enlarged view of the rubbing seal member and the rubber blade of FIG. 9.

[Example 1]
Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. First, an overview of the entire image forming apparatus in the present embodiment will be described.

(Overview of the entire image forming apparatus)
In FIG. 1, the laser beam printer 1 includes a feeder unit 10 that feeds paper (not shown) at the bottom of a main body case 2. The paper is transported to the transfer position by changing the direction from the front direction to the rear direction by various rollers provided in the feeder unit 10.

  The photosensitive drum 20 is made of a positively chargeable material and is pivotally supported by the main body case 2. Further, the photosensitive drum 20 is rotationally driven in the direction of the arrow by a driving unit (not shown). The charger 30 is composed of a positively-charged scorotron charger that generates corona discharge from a charging wire.

  The laser scanner unit 40 includes a laser generator (not shown) that generates a laser beam L for forming an electrostatic latent image on the photosensitive drum 20, a polygon mirror 41 that is rotationally driven, and other various reflection mirrors and lenses. It is configured to include.

  As shown in FIG. 2, the developing device 50 includes a case 51 as an example of a housing of the present invention in which a toner storage chamber 52 as a developer chamber is formed. In the toner storage chamber 52, an agitator 53, A cleaning member 54 is rotatably provided around the rotation shaft 55. The toner storage chamber 52 stores toner as a positively chargeable nonmagnetic one-component developer having electrical insulation. Further, on the photosensitive drum 20 side of the toner storage chamber 52 (see FIG. 1), a developing chamber 57 that performs development by communicating with the toner storage chamber 52 through the toner supply port A is formed, and serves as a supply roller 58 and a developer carrier. The developing roller 59 is rotatably supported. As will be described in detail later, the toner on the developing roller 59 is regulated to a predetermined layer thickness by a layer thickness regulating blade 64 having a thin plate-like elasticity, and is supplied for development.

  Here, the developing roller 59 as a developer carrying member has a coating layer of a resin or rubber material containing fluorine on a base material on which conductive silicone rubber is formed. The substrate may be composed of conductive urethane rubber. The toner stored in the toner storage chamber 52 is a positively charged nonmagnetic one-component developer.

  The transfer roller 21 is rotatably supported, and is configured to reliably transfer the toner image on the photosensitive drum 20 to a sheet by an applied voltage.

  The fixing unit 70 is provided further downstream in the sheet conveyance direction from the pressure contact portion between the photosensitive drum 20 and the transfer roller 21, and the toner image transferred to the sheet is conveyed by the heating roller 71 and the pressing roller 72. During heating, the sheet is fixed by pressing while heating. A discharge tray 75 is provided on the downstream side of the fixing unit 70 in the transport direction and on the downstream side of the discharge roller 74.

  The photosensitive drum 20, the transfer roller 21, the charger 30, and the developing device 50 described above are accommodated in the process cartridge 2a, and the process cartridge 2a is detachably provided to the laser beam printer 1. Yes. Further, the developing device 50 is detachably attached to the process cartridge 2a as a developing cartridge.

  In the laser beam printer 1 of the present embodiment as described above, when the surface of the photosensitive drum 20 is uniformly charged by the charger 30, and the laser light L modulated according to the image information is emitted from the laser scanner unit 40, An electrostatic latent image is formed on the surface of the photosensitive drum 20. The electrostatic latent image is visualized with toner by the developing device 50, and the visible image formed on the photosensitive drum 20 is conveyed to the transfer position by the photosensitive drum 20. At the transfer position, paper is supplied from the feeder unit 10, and the visible image is transferred to the paper by a transfer bias applied by the transfer roller 21. The toner remaining on the photosensitive drum 20 after the transfer is collected in the developing chamber 57 by the developing roller 59.

Next, the sheet is conveyed to the fixing unit 70, nipped and conveyed by the heating roller 71 and the pressing roller 72 of the fixing unit 70, and thermally fixed on the sheet. Then, the paper is discharged by a paper discharge roller 74 to a paper discharge tray 75 above the laser beam printer 1, and the image forming operation ends.
(Configuration for toner seal)
Next, the configuration of the toner seal for preventing the toner from leaking from the case 51 at both ends in the axial direction of the developing roller 59 of the developing device 50 will be described. In addition, although the structure of the seal | sticker provided in one axial direction edge part of case 51 is demonstrated here, the structure of the other edge part is also the same.

  As shown in FIG. 3, the axial end of the developing roller 59 in the developing device 50 is opened at the front surface of the case 51 as an opening 49, and the side wall 31 is supported for mounting the developing roller 59. As shown in FIG. 4, an upper side seal 34, a blade side seal 35, and a lower side seal as shown in FIG. 36 is provided.

  The side seal 33, the upper side seal 34, the blade side seal 35, and the lower side seal 36 reliably prevent toner leakage at the axial end of the developing roller 59.

  The end portion of the case 51 where the side seal 33 is provided is formed in a curved shape along the outer peripheral surface of the developing roller 59 in order to bring the side seal 33 and the developing roller 59 into close contact with each other.

  Further, the support hole 32 is opened at the front end thereof, and is formed so as to receive the roller shaft 60 of the developing roller 59 along the opening 37.

  As shown in FIG. 4, the upper side seal 34 is formed in a substantially rectangular plate shape having a predetermined thickness, is made of a sponge member such as urethane, and is formed on the upper side of the width direction side end portion of the case 51 adjacent to the side wall 31. It is arrange | positioned above the attachment member 61 of the thickness control blade 64, and is stuck by the double-sided tape etc.

  The blade side seal 35 is provided at the lower end of the leaf spring member 66 at the end in the width direction of the leaf spring member 66 of the layer thickness regulating blade 64, and the back blade provided on the back surface (rear surface) of the leaf spring member 66. A seal 67 and a front blade seal 68 provided on the surface (front surface) of the leaf spring member 66 are provided.

  The attachment member 61 of the layer thickness regulating blade 64 includes a plate-like back support member 69 extending along the axial direction of the developing roller 59, and a front support having a substantially L-shaped cross section disposed to face the back support member 69. A member 81 is provided, and is fixed to the upper portion of the case 51 by a screw 82 with the leaf spring member 66 sandwiched between the back support member 69 and the front support member 81.

  The back blade seal 67 has a substantially rectangular plate shape having a predetermined thickness and is made of a sponge member such as urethane. The back blade seal 67 is formed on the back surface of the leaf spring member 66 in a state where the upper end portion is in contact with the lower end portion of the back support member 69. It is attached with double-sided tape.

  The front blade seal 68 has a substantially rectangular plate shape having a predetermined thickness, is made of a sponge member such as urethane, and is adhered to the surface of the leaf spring member 66 facing the back blade seal 67 with a double-sided tape or the like. ing.

  Further, as shown in FIG. 3, the lower side seal 36 is formed in a substantially rectangular plate shape having a predetermined thickness, is made of a sponge member such as urethane, is an end portion in the width direction of the case 51, and is the side described below. Adjacent to the inside of the seal 33, the case 51 is attached to the lower surface of the case 51 with double-sided tape or the like.

  By providing the lower side seal 36, it is possible to prevent toner leakage at a boundary portion where the side seal 33 and the lower film 83 (see FIG. 3) described below are attached.

  The side seal 33 is provided so as to be in sliding contact with the outer peripheral surface of the developing roller 59 at the end in the width direction of the case 51 adjacent to the side wall 31.

  The side seal 33 includes a sponge seal member 84 and a rubbing seal member 96 as an example of the seal member of the present invention laminated on the sponge seal member 84. The sponge seal member 84 is made of an elastic foam that is a sponge member such as urethane. The sponge seal member 84 is formed in a sheet shape having a certain thickness so as to be compressed when the developing roller 59 is mounted and to express a predetermined pressing force.

  Further, as shown in FIG. 3, the sponge seal member 84 has a substantially rectangular base portion 85 whose upper surface is formed as a sticking surface of the rubbing seal member 96 to be described below, and a side surface 89 of the base portion 85. A projecting portion 86 is integrally provided that projects in a rectangular shape from the central portion in the direction (that is, the rotation direction of the developing roller 59) toward the inner side in the axial direction of the developing roller 59. That is, the side surface 89 is formed with a projecting surface 90 that forms the projecting portion 86 and a non-projecting surface 91. A rectangular recess 87 is formed in the base 85 at a position opposite to the side on which the protrusion 86 is formed.

  More specifically, the protrusion 86 has a protrusion length corresponding to an image forming area (an area where an electrostatic latent image is formed) of the photosensitive drum 20 of the laser printer 1 as shown in FIG. The length does not overlap the first area D1 of the roller 59 and the second area D2 of the developing roller 59 corresponding to the maximum width of the paper used in the laser printer 1.

  The sponge seal member 84 is disposed in a state in which the recess side end 88 which is the side end on the side where the recess 87 is formed is in contact with the side wall 31 of the case 51. Is positioned.

  Further, as shown in FIG. 4, the sponge seal member 84 has its upper end pressed against the lower end of the back blade seal 67 of the blade side seal 35, and as shown in FIG. In a state where the side seal 36 and the case 51 overlap in the width direction, the side seal 36 is attached with a double-sided tape or the like.

  If the upper end of the sponge seal member 84 is brought into pressure contact with the back blade seal 67 of the blade side seal 35, the leakage of toner at the boundary between the sponge seal member 84 and the blade side seal 35 due to the contact between the sponge members. Can be prevented.

  Further, if the lower end portion of the sponge seal member 84 is overlapped in the width direction of the lower side seal 36 and the case 51, a boundary portion between the sponge seal member 65 and the lower side seal 57 is brought about by contact between the sponge members. The toner can be prevented from leaking.

  Further, as will be described in detail later, as shown in FIG. 4, a sponge seal member 84 and a rubbing seal member 96 are laminated along the curved shape of the case 51. Therefore, the surface of the rubbing seal member 96 is formed in an arc shape along the outer peripheral surface of the developing roller 59 and is in close contact with the developing roller 59.

  The developing roller 59 is rotatably mounted and supported on the case 51 by inserting the roller shaft 60 of the developing roller 59 along the support hole 32 from the front side where the case 51 is opened. As a result, the outer peripheral surface of the end portion in the axial direction of the developing roller 59 comes into slidable contact with the surface of the rubbing seal member 96 in close contact with the outer peripheral surface of the end portion in the axial direction of the developing roller 59. Between the surfaces of 96, toner leakage from the axial end to the outside of the case 51 due to the rotational drive of the developing roller 59 during development is sealed.

  Further, a lower film 83 (see FIGS. 3 and 4) made of a PET (polyethylene terephthalate) sheet, a urethane rubber film, or the like is attached to the upper surface of the lower end portion of the case 51 with a double-sided tape over the entire width direction. Thus, leakage from the lower side of the case 51 is prevented.

  Next, a specific configuration of the layer thickness regulating blade 64 will be described. As shown in FIG. 5, the layer thickness regulating blade 64 includes a leaf spring member 66, a rubber blade 92 as an example of the layer thickness regulating member of the present invention, an attachment member 61, and the like. As described above, the leaf spring member 66 is sandwiched between the mounting members 61 and screwed with the screws 82 so as to be fixed from the upper end portion to the lower end portion of the case 51, and the longitudinal direction of the case 51, that is, the developing roller 59. It is provided so as to extend in the axial direction.

  The leaf spring member 66 is provided with notches 94 at both longitudinal ends of the lower end thereof. Further, on both ends of the notch 94, there are provided attachment surfaces 93 to which the front blade seal 68 is attached.

  The rubber blade 92 is affixed to the lower end portion of the surface of the leaf spring member 66. The rubber blade 92 is provided so as to face the developing roller 59, and has a contact surface 97 that is in pressure contact with at least a range of the developing roller 59 wider than the peripheral surface corresponding to the developing region D1 (see FIG. 2). The contact surface 97 of the rubber blade 92 is rubbed from the lower end (upstream in the rotation direction of the developing roller 59) to the upper end (downstream) as the developing roller 59 rotates counterclockwise in FIG. The The developing roller 59 that rotates rotates the toner into a thin layer with the rubber blade 92.

  Further, as shown in FIG. 5, the length of the rubber blade 92 in the longitudinal direction is lower than the length L1 on the upper end side (downstream in the rotation direction of the developing roller 59) (upstream in the rotation direction of the developing roller 59). The length L2 is longer. That is, the length L2 on the lower end side is longer than the length L1 on the upper end, so that inclined surfaces 95 are formed on both end surfaces in the longitudinal direction of the rubber blade 92. It is desirable that the lower end portion of the inclined surface 95 is formed so as to advance to the attaching surface 93 formed on the leaf spring member 66.

  Next, the configuration of the rubbing seal member 96 will be described with reference to FIGS. The rubbing seal member 96 is composed of a fabric member made of cashmere fibers, and the fabric member is formed in a substantially rectangular sheet shape.

  As shown in FIG. 6, first, the rubbing seal member 96 has inclined surfaces 95 formed on both end surfaces in the longitudinal direction of the rubber blade 92 on the affixing surface 93 at the end portion in the width direction of the case 51 adjacent to the side wall 31. Attached with double-sided tape etc. It is desirable that the rubbing seal member 96 be attached in a direction along the non-projecting surface 91 of the sponge seal member 84. At this time, the inclined surface 95 is in close contact with the rubbing seal member 96 such that the lower end side bites into the rubbing seal member 96 rather than the upper end side.

  Next, it sticks toward the lower end direction of case 51 along the non-projecting surface 91 of the sponge seal member 84. Then, in the vicinity of the projecting surface 90 of the sponge seal member 84, the attaching direction is changed. Specifically, the rubbing seal member 96 is bent toward the side wall 31 so as to form an acute angle (angle β in FIG. 7) with respect to the affixing direction of the rubbing seal member 96 on the affixing surface 93. (See FIGS. 7 and 8). At this time, it is desirable to apply the rubbing seal member 96 so that the lower end of the base 85 of the sponge seal member 84 is exposed by about 0.5 to 1 mm.

  Then, as shown in FIG. 4, the rubbing seal member 96 is affixed with a double-sided tape so that its lower end is wound around the lower end of the case 51.

  As a result, the rubbing seal member 96 is laminated on the base 81 of the sponge seal member 84 at the end in the width direction of the casing 52 adjacent to the side wall 31 as shown in FIG. 8, and as shown in FIG. The upper end covers the vicinity of the upper end of the front blade seal 68, and the lower end extends further downward from the lower end of the sponge seal member 84, covering the lower end of the case 51 in a wound shape. It is pasted in such a state.

  Since the rubbing seal member 96 is pasted from the middle of the upper end portion toward the side wall 31, the lower end portion of the rubbing seal member 96 moves away from the first region D1 of the developing roller 59 which is an image forming region. Will be pasted. Since this sticking method makes it difficult for the toner to enter from the first region D1, the rotation of the developing roller 59 during development is between the outer peripheral surface of the axial end portion of the developing roller 59 and the surface of the rubbing seal member 96. Toner leakage from the axial end portion of the drive to the outside of the case 51 is further sealed.

  Further, the length of both end faces in the longitudinal direction of the rubber blade 92 is the length on the lower end side (upstream in the rotational direction of the developing roller 59) than the length L1 on the upper end side (downstream in the rotational direction of the developing roller 59). By forming L2 longer, inclined surfaces 95 are formed on both end faces. The rubbing seal member 96 is in contact with the inclined surface 95 at its upper end. Therefore, the gap between the rubber blade 92 and the rubbing seal member 96 is less likely to be formed on the upstream side in the rotation direction of the developing roller 59. As a result, the toner on the developing roller 59 can be prevented from leaking between the sliding seal member 96 and the rubber blade 92. Further, as shown in FIG. 6, the lower end side of the inclined surface 95 extends away from the first region D1, so that the toner does not easily enter.

Further, the lower end of the inclined surface 95 of the rubber blade 92 is pressed against the rubbing seal member 96 so as to bite. By biting into the rubbing seal member 96, the adhesion becomes higher toward the upstream side in the rotation direction of the developing roller 59. Accordingly, toner leakage between the sliding seal member 96 and the rubber blade 92 can be prevented.
[Example 2]
Next, other embodiments of the present invention will be described. Here, only the way of attaching the rubbing seal member 96 is different, and the other configuration is the same as that of the first embodiment. In addition, description is abbreviate | omitted about the part which has the same structure as Example 1, and attaches | subjects and demonstrates the same code | symbol.

  As shown in FIGS. 9 and 10, the sliding seal member 96 having a rectangular shape is formed on both end surfaces in the longitudinal direction of the rubber blade 92 on the affixing surface 93 at the end in the width direction of the case 51 adjacent to the side wall 31. Then, they are pressed together along the inclined surface 95 and attached with a double-sided tape or the like. And it affixes on the base material 87 of the sponge seal member 84, without changing an affixing direction as it is. As a result, the rubbing seal member 96 is attached so that the lower end portion of the rubbing seal member 96 faces the side wall 31 so as to form an acute angle β with respect to the non-projecting surface 91 of the sponge seal member 84. More specifically, it is desirable to affix the rubbing seal member 96 so that the lower end of the base portion 85 of the sponge seal member 84 is exposed by about 0.5 to 1 mm.

  As described above, when the rubbing seal member 96 is press-contacted along the inclined surface 95 formed on the rubber blade 92, there is no gap between the rubbing seal member 96 and the rubber blade 92. Therefore, it is possible to prevent the toner on the developing roller 59 from leaking between the sliding seal member 96 and the rubber blade 92.

  In the embodiment described above, the rubbing seal member 96 is configured as a woven member of a cashmere-based fiber member. However, in addition to the woven member, for example, it may be configured as felt, knitted fabric, flocking, non-woven fabric, or the like. Moreover, you may comprise using a polyester-type fiber member.

  Furthermore, in the above-described embodiment, the developing device 50 is applied to a developing cartridge that can be attached to and detached from the laser printer 1. However, the developing device may be configured to be provided in the laser printer 1.

DESCRIPTION OF SYMBOLS 1 Laser printer 2 Main body case 50 Developing device 51 Case 59 Developing roller 64 Layer thickness control blade 84 Sponge seal member 92 Rubber blade 95 Inclined surface 96 Rub seal member

Claims (4)

A housing for containing the developer;
A developer carrier rotatably supported on both side walls near the opening of the housing;
A layer thickness regulating member that regulates the thickness of the developer on the developer carrying body at a contact surface that extends in the rotation axis direction of the developer carrying body and contacts the peripheral surface of the developer carrying body;
Near the both side walls of the opening of the housing, it is provided so as to rub against the peripheral surfaces on both ends of the developer carrier, and contacts the both end surfaces in the longitudinal direction of the layer thickness regulating member. A developing device that forms a visible image by causing a thin layer of developer on the developer carrying member to face an electrostatic latent image,
The longitudinal end faces of the layer thickness regulating member are
An inclined surface is formed such that the length in the longitudinal direction of the contact surface is longer on the upstream side than the downstream side in the rotation direction of the developer carrier,
The seal member is formed continuously with a downstream portion that extends in an orthogonal direction orthogonal to the rotation axis direction and is pressed against the inclined surface of the layer thickness regulating member, and the downstream portion. And an upstream portion that is upstream of the downstream portion in the rotation direction of the developer carrier, and
The boundary part between the downstream part and the upstream part is located upstream of the upstream end in the rotation direction of the developer carrier on the contact surface of the layer thickness regulating member,
The downstream portion extends in a direction perpendicular to the rotation axis direction from the upstream end in the rotation direction of the developer carrier on the contact surface of the layer thickness regulating member to the boundary portion,
The developing device, wherein the upstream portion extends from the boundary portion toward the upstream side in the rotation direction so as to form an angle with respect to the orthogonal direction and toward the outside in the rotation axis direction .   2. A process cartridge, wherein the developing device according to claim 1 is detachable and includes an electrostatic latent image carrier, and is configured to be detachable from the image forming apparatus main body.   A developing cartridge configured to be detachable from the process cartridge or the image forming apparatus.   An image forming apparatus comprising the developing device according to claim 1 or the process cartridge according to claim 2.