JP6264886B2 - Development device - Google Patents

Description

  The present invention relates to a developing device including a seal member disposed between both ends of a developing roller and a frame.

  A developing device used in an image forming apparatus such as a laser printer includes a developing roller, a frame for containing a developer, and a seal member disposed between both ends of the developing roller and the frame. In the developing device of Patent Document 1 (see FIG. 8), the outer end of the seal member extends beyond the end of the developing roller (roller portion) in the rotation axis direction of the developing roller.

JP 2001-154480 A

  By the way, in the configuration in which the end of the seal member extends to the outside of the end of the developing roller, the developing roller is pressed against the seal member, so that a relatively large pressing force is applied to the seal member from the end of the developing roller. The member is crushed. As a result, a force to move outward in the rotational axis direction acts on the seal member. Therefore, when the developing roller rotates in this state, the seal member moves outward in the rotational axis direction to create a gap between the seal member and the frame. The developer may leak from the gap.

  The present invention has been made in view of the above background, and provides a developing device capable of suppressing developer leakage in a configuration in which the end of the seal member extends to the outside of the end of the developing roller. With the goal.

In order to achieve the above-described object, the developing device of the present invention includes a developing roller having a roller body configured to carry a developer, a frame that rotatably supports the developing roller, and both ends of the roller body. And an elastically deformable seal member disposed between the portion and the frame.
In the rotation axis direction of the developing roller, the outer end of the seal member is positioned outside the end of the roller body in the rotation axis direction of the seal member.
The seal member has a slit extending in a rotation direction of the developing roller on a contact surface that contacts the roller body.
The slit is located inside the end of the roller body in the rotational axis direction in the rotational axis direction.

  According to such a configuration, even when the portion outside the slit of the seal member tries to move outward when the developing roller rotates, the slit is slightly opened, and the portion inside the slit of the seal member is It becomes difficult to apply force to move outward. Thereby, since the adhesiveness between the seal member and the frame can be ensured, developer leakage can be suppressed.

  In the developing device described above, the frame may have an inner contact surface that contacts an inner end of the seal member in the rotation axis direction.

  According to this, the position of the seal member in the rotation axis direction can be determined by bringing the inner end of the seal member into contact with the inner contact surface.

  In the developing device described above, the seal member includes an elastic member, and a contact member that is disposed between the elastic member and the developing roller and contacts the roller body, and the slit is the contact surface. To the middle of the elastic member.

  In the developing device, the seal member is disposed between the elastic member, the elastic member and the developing roller, and contacts the roller main body, and the elastic member is bonded to the frame. An adhesive member, and the slit has a depth from the contact surface to the middle of the adhesive member.

  In the developing device, the slit may have a length from one end to the middle of the seal member in the rotation direction.

  According to these, since the size of the parts can be secured as compared with the configuration in which the seal member is completely divided by the slit, the seal member can be easily attached to the frame, and the developing device is easily assembled. be able to.

  In the developing device described above, the seal member includes an elastic member, and a contact member that is disposed between the elastic member and the developing roller and contacts the roller body. The contact member is a cloth material. It can be set as the structure which is.

  In the developing device described above, the seal member includes a plurality of seal constituent members configured as separate members arranged in the rotation axis direction, and the slit is formed between adjacent seal constituent members. can do.

  According to this, for example, by changing the material of each seal constituent member, the functions of the seal constituent member arranged on the inner side and the seal constituent member arranged on the outer side can be made different. It is possible to realize a configuration that does not leak easily.

  In the developing device described above, the seal member includes a first portion disposed on the innermost side in the rotation axis direction, and a second portion disposed on the outer side of the first portion, and The two portions can be configured to be more difficult to deform than the first portion. Specifically, for example, the first part has a first elastic member, the second part has a second elastic member, and the second elastic member is harder than the first elastic member. It can be configured.

  According to this, since the second part is difficult to be deformed even if the seal member moves outward, the second part is supported and can be prevented from falling outward due to the deformation of the first part. And the frame can be secured. Thereby, developer leakage can be further suppressed.

  In the developing device described above, a plurality of the slits may be formed side by side in the rotation axis direction.

  According to this, since the seal member can easily follow the shape of the developing roller, the adhesion between the seal member and the developing roller can be improved, and developer leakage can be further suppressed.

  According to the present invention, developer leakage can be suppressed in the configuration in which the end of the seal member extends to the outside of the end of the developing roller.

FIG. 2 is a diagram illustrating a schematic configuration of a laser printer in which a developing cartridge as an example of a developing device is used. It is sectional drawing of a process cartridge. FIG. 3 is an exploded perspective view of a developing cartridge. It is an expansion perspective view of the installation surface and seal member concerning a 1st embodiment. It is a figure which shows the structure of the left end part vicinity of the developing roller which concerns on 1st Embodiment. It is a figure which shows the structure of the edge part vicinity of the developing roller which concerns on a comparative example. It is a perspective view of the sealing member which concerns on 2nd Embodiment. It is the figure (a) which shows the sealing member which concerns on 3rd Embodiment, and the figure (b) which shows the state which assembled | attached the developing roller. It is a perspective view of the seal member concerning a 4th embodiment. It is a perspective view (a) of a seal member concerning the 1st modification, and (b). It is a perspective view of the seal member concerning the 2nd modification.

[First Embodiment]
Next, the first embodiment will be described in detail with reference to the drawings as appropriate. In the following description, first, a schematic configuration of a laser printer in which the developing device according to the embodiment is used will be described, and then a detailed configuration of the developing device will be described. In the following description, the direction will be described with reference to the user who uses the laser printer 1. Specifically, the left side of FIG. 1 as viewed from the user is “front”, the right side of FIG. 1 as viewed from the user is “rear”, and the front side of FIG. 1 is “right”. ”, The left side of the page is“ left ”. Further, the vertical direction in FIG.

<Schematic configuration of laser printer>
As shown in FIG. 1, the laser printer 1 includes a feeder unit 4 for feeding a sheet 3 into a main body casing 2, an image forming unit 5 for forming an image on the sheet 3, and the like.

  The feeder unit 4 includes a paper feed tray 6 that is detachably attached to the bottom of the main body casing 2, a paper pressing plate 7 provided in the paper feed tray 6, and various types that carry the paper 3 and remove paper dust. The roller 11 is mainly provided. In the feeder unit 4, the sheet 3 in the sheet feeding tray 6 is moved upward by the sheet pressing plate 7 and conveyed to the image forming unit 5 by various rollers 11.

  The image forming unit 5 includes a scanner unit 16, a process cartridge 17, a fixing unit 18, and the like.

  The scanner unit 16 is provided at an upper portion in the main body casing 2 and includes a laser light emitting unit (not shown), a polygon mirror 19 that is rotationally driven, lenses 20 and 21, reflecting mirrors 22, 23, and 24. In the scanner unit 16, the laser beam is irradiated on the surface of the photosensitive drum 27 by high-speed scanning through a path indicated by a chain line in the drawing.

  The process cartridge 17 is configured to be detachably attached to the main casing 2 by appropriately opening a front cover 2A provided on the front side of the main casing 2. The process cartridge 17 mainly includes a developing cartridge 28 as an example of a developing device and a drum unit 39.

  The developing cartridge 28 is detachably attached to the main casing 2 while being attached to the drum unit 39. As shown in FIG. 2, the developing cartridge 28 mainly includes a developing roller 31, a layer thickness regulating blade 32, a supply roller 33, and an accommodating portion 34 that accommodates toner as an example of a developer.

  In the developing cartridge 28, the toner in the container 34 is stirred by the rotating agitator 34 </ b> A and then supplied to the developing roller 31 by the supply roller 33. The toner supplied to the developing roller 31 enters between the layer thickness regulating blade 32 and the developing roller 31 as the developing roller 31 rotates, and is carried on the developing roller 31 as a thin layer having a constant thickness. .

  The drum unit 39 mainly includes a photosensitive drum 27, a charger 29, and a transfer roller 30. In the drum unit 39, the surface of the photosensitive drum 27 is uniformly charged by the charger 29 and then exposed by high-speed scanning of the laser beam from the scanner unit 16, whereby image data is formed on the photosensitive drum 27. A based electrostatic latent image is formed.

  Thereafter, the toner carried on the developing roller 31 is supplied to the photosensitive drum 27, whereby a toner image is formed on the photosensitive drum 27. Then, the sheet 3 is conveyed between the photosensitive drum 27 and the transfer roller 30, whereby the toner image on the photosensitive drum 27 is transferred to the sheet 3.

  As shown in FIG. 1, the fixing unit 18 mainly includes a heating roller 41 and a pressure roller 42 that is disposed to face the heating roller 41 and pressurizes the heating roller 41. In the fixing unit 18, the toner transferred onto the paper 3 is thermally fixed while the paper 3 passes between the heating roller 41 and the pressure roller 42. The paper 3 thermally fixed by the fixing unit 18 is discharged onto a paper discharge tray 46 by a paper discharge roller 45.

<Detailed configuration of developing cartridge>
2 and 3, the developing cartridge 28 further includes a lower film 35, a frame 100, and a seal member 200 in addition to the developing roller 31, the layer thickness regulating blade 32, the supply roller 33, and the like. ing.

  In the following description, the rotation axis direction of the developing roller 31 corresponding to the left-right direction is referred to as “rotation axis direction”, the radial direction of the developing roller 31 is referred to as “radial direction”, and the rotation direction of the developing roller 31 ( 2) (refer to the arrow in FIG. 2) is referred to as “rotation direction”.

  The developing roller 31 mainly includes a shaft portion 31A and a roller main body 31B configured to carry toner on the surface thereof. The roller body 31B is formed by covering the surface of the shaft portion 31A with conductive rubber or the like.

  The layer thickness regulating blade 32 contacts the surface of the roller body 31B of the rotating developing roller 31 and scrapes off excess toner adhering to the surface of the roller body 31B, thereby reducing the amount of toner carried on the roller body 31B. A member configured to be regulated. The layer thickness regulating blade 32 mainly includes a plate-like member 32A formed of sheet metal and a contact member 32B formed of rubber and contacting the roller body 31B, and is fixed to the frame 100 by screws 38. ing.

  The lower film 35 is a sheet-like member made of a resin such as polyethylene terephthalate (PET), and is arranged in a state of extending in the rotation axis direction between the developing roller 31 and the frame 100 and in contact with the lower portion of the roller body 31B. ing. By providing such a lower film 35, toner leakage from between the lower portion of the roller body 31B and the frame 100 is suppressed.

  As shown in FIG. 3, the frame 100 is a member that forms the accommodating portion 34 and supports the developing roller 31, the layer thickness regulating blade 32, the supply roller 33, and the like. The frame 100 rotatably supports the developing roller 31, the supply roller 33, and the like. The frame 100 includes an opening 110 that is long in the rotational axis direction for supplying the toner in the container 34 to the developing roller 31 via the supply roller 33, an installation surface 120 formed on each of the left and right sides of the opening 110, and an inner contact It mainly has a contact surface 130 and an outer contact surface 140.

  4 and 5 show a configuration in the vicinity of the left installation surface 120. FIG. In the present embodiment, since the configuration near the installation surface 120 is substantially the same, the configuration near the installation surface 120 on the right side is not shown.

  As shown in FIGS. 4 and 5, the installation surface 120 is a surface on which the seal member 200 is installed facing the seal member 200 in the radial direction (corresponding to the vertical direction in FIG. 5). Specifically, the installation surface 120 is formed as a surface substantially parallel to the rotation axis direction and long in the rotation direction.

  The inner contact surface 130 is a surface located inside the installation surface 120 in the rotation axis direction. Specifically, the inner abutment surface 130 is a side surface of the film attachment portion 105 that is long in the direction of the rotation axis to which the lower film 35 is attached, and extends from the inner end in the rotation axis direction of the installation surface 120 toward the radially inner side. , Formed as a plane substantially parallel to the radial direction (a plane along the radial direction). The inner contact surface 130 is in contact with an inner end 201 that is an inner end in the rotation axis direction of a seal member 200 described later.

  The outer contact surface 140 is a surface that is positioned outside the installation surface 120 in the rotation axis direction and faces the inner contact surface 130. Specifically, the outer contact surface 140 is a surface on the inner side in the rotational axis direction of the protruding portion 102 that projects inward from the inner surface in the rotational axis direction of the side wall 101 of the frame 100, and is located on the outer side in the rotational axis direction of the installation surface 120. It is formed as a plane substantially parallel to the inner contact surface 130 that extends radially inward from the end of the inner contact surface 130. The outer abutment surface 140 abuts on the outer end 202 which is the outer end of the seal member 200 in the rotation axis direction.

  In this embodiment, the seal member 200 has the inner end 201 in contact with the inner contact surface 130 and the outer end 202 in contact with the outer contact surface 140. It is arranged in a state sandwiched between.

  The seal member 200 is a member for suppressing toner leakage from between both ends of the developing roller 31 and the frame 100, and is disposed between both ends of the developing roller 31 and the frame 100. Specifically, the seal member 200 has the outer end 202 extending outside the end 31E in the rotation axis direction of the roller body 31B in the rotation axis direction, and the inner end 201 side on the end of the roller body 31B and the frame 100. It is arrange | positioned between the installation surfaces 120 of.

  The seal member 200 mainly includes an elastic member 210, a contact member 220 disposed between the elastic member 210 and the developing roller 31, and an adhesive member 230 disposed between the elastic member 210 and the installation surface 120. It is configured.

  The elastic member 210 is provided for the purpose of bringing the contact member 220 into close contact with the developing roller 31 by a restoring force when being crushed, and is made of an elastically deformable material such as urethane sponge.

  The contact member 220 is a member that contacts the roller body 31B. The contact member 220 is formed of a cloth material for the purpose of reducing sliding resistance with the roller body 31B in order to smoothly rotate the developing roller 31. Here, the cloth material means a member made by combining fibers, and it does not matter whether it is a woven cloth such as a mesh or a non-woven cloth such as felt. In addition, when a fabric material is subjected to a tensile load, the shape formed by the fibers being combined with the background is deformed, or the fibers that have been intertwined and bent are stretched, so that the stretchability in a predetermined direction. It is desirable to have. The contact member 220 is desirably formed so that the expansion and contraction direction of the cloth material is along the rotation axis direction when the seal member 200 is installed on the installation surface 120.

  The adhesive member 230 is a member for adhering the elastic member 210 (seal member 200) to the installation surface 120 of the frame 100. The adhesive member 230 can be formed, for example, by applying a pressure-sensitive adhesive to the surface of the elastic member 210 opposite to the contact member 220 side, or applying a double-sided tape. In order to suppress a decrease in the adhesive force, a release sheet (not shown) is provided on the surface of the adhesive member 230 (the surface opposite to the elastic member 210 side) before being attached to the installation surface 120. Is desirable.

  The seal member 200 has a slit 240 on the contact surface 221 that contacts the roller body 31B. The slit 240 is formed by making a cut in the seal member 200. In the rotation axis direction, the slit 240 is inside the end 31E of the roller body 31B, more specifically, from a central portion between the end 31E and the inner contact surface 130. It is located on the end 31E side. The slit 240 has a depth from the contact surface 221 that is the surface of the contact member 220 to the middle of the adhesive member 230 (for example, about half the thickness of the adhesive member 230). In addition, the slit 240 is formed from the upstream end to the downstream end of the seal member 200 in the rotational direction so as to extend along the rotational direction.

Next, the effect of this embodiment comprised as mentioned above is demonstrated.
As shown in FIG. 6 as a comparative example, in the configuration in which the outer end 202 of the seal member 900 extends to the outside of the end 31E of the roller body 31B of the developing roller 31, if the slit is not formed, the developing roller 31 By being attached to the frame 100 and being pressed against the seal member 900, a relatively large pressing force is applied to the outer end portion of the seal member 900 from the end 31E of the roller body 31B, and the outer end portion of the seal member 200 is pushed. It will be crushed.

  Then, the sealing member 900 presses the end 31E of the roller main body 31B by the restoring force of the sealing member 900, so that a force to move outward in the rotation axis direction indicated by the arrow acts on the sealing member 900. In this state, when the developing roller 31 rotates, the contact member 220 side of the seal member 900 moves outward in the rotation axis direction, and a gap is formed between the inner end 201 and the inner contact surface 130, and toner leaks from the gap. there is a possibility. Such a possibility becomes conspicuous when the diameter of the end portion of the roller body 31B is larger than the slightly inner portion.

  As shown in FIG. 5, in the present embodiment, the seal member 200 has the slit 240 on the contact surface 221, so that when the developing roller 31 rotates, a portion outside the slit 240 of the seal member 200 faces outward. Even if it tries to move, the slit 240 is slightly opened, so that a force to move outward is less likely to be applied to a portion inside the slit 240 of the seal member 200. Thereby, the adhesiveness between the seal member 200 and the frame 100, specifically, the inner end 201 and the inner contact surface 130 can be secured, and thus toner leakage can be suppressed.

  In this embodiment, since the frame 100 has the inner contact surface 130 and the outer contact surface 140, the ends 201 and 202 of the seal member 200 are brought into contact with the inner contact surface 130 and the outer contact surface 140. Thus, the position of the seal member 200 in the rotation axis direction can be determined. Further, in the present embodiment, since the seal member 200 is sandwiched between the inner contact surface 130 and the outer contact surface 140, the positional deviation of the seal member 200 can be further suppressed, and toner leakage can be further reduced. Can be suppressed.

  Further, in the present embodiment, since the slit 240 is formed at a depth from the contact surface 221 to the middle of the adhesive member 230, the size of the part is larger than the configuration in which the seal member is completely divided by the slit. Can be secured. In other words, the seal member 200 does not become too small. As a result, the seal member 200 can be easily attached to the frame 100, so that the developing cartridge 28 can be easily assembled.

  In addition, when the sealing member 200 is formed so that the expansion / contraction direction of the cloth material constituting the contact member 220 is along the rotation axis direction, a portion outside the slit 240 of the sealing member 200 will move outward. As a result, the contact member 220 can be extended. Thereby, since the position shift of the whole seal member 200 can be suppressed, toner leakage can be suppressed.

[Second Embodiment]
Next, a second embodiment will be described. In the embodiments described below, including this embodiment, components different from those of the first embodiment will be mainly described in detail, and the same components as those described in the above will be denoted by the same reference numerals. The description will be omitted.

  As shown in FIG. 7, the slit 240 is formed with a length from one end of the seal member 200 to the middle in the rotation direction of the developing roller 31 indicated by an arrow. Specifically, the slit 240 is formed with a length from the upstream end of the seal member 200 to the front of the downstream end in the rotation direction.

  In this embodiment, since the seal member 200 is not too small as compared with the configuration in which the seal member is completely divided by the slit, the seal member 200 can be easily attached to the frame 100. The developing cartridge 28 can be easily assembled. Although not shown, the slit 240 is formed with a length from the downstream end of the seal member 200 to the upstream end in the rotational direction, contrary to the configuration shown in FIG. May be.

[Third Embodiment]
Next, a third embodiment will be described.
As shown in FIG. 8A, a plurality of slits 240, specifically two, are formed side by side in the rotation axis direction. The seal member 200 is disposed on the outermost side with the first part 200A disposed on the innermost side, the second part 200B disposed on the outer side of the first part 200A in the rotational axis direction, with the slit 240 as a boundary. And the third portion 200C.

The first portion 200A includes an elastic member 210 as a first elastic member, a contact member 220, and an adhesive member 230, and the third portion 200C includes an elastic member 210 as a third elastic member, and a contact member. 220 and an adhesive member 230 . Further, the second portion 200 </ b> B includes a second elastic member 260, a contact member 220, and an adhesive member 230. The adhesive member 230 is common among the first part 200A, the second part 200B, and the third part 200C because each slit 240 is formed at a depth from the contact surface 221 to the middle of the adhesive member 230. It is a member of.

  Similar to the elastic member 210, the second elastic member 260 is provided for the purpose of bringing the contact member 220 into close contact with the developing roller 31 by a restoring force when crushed, but is harder than the elastic member 210 ( It is made of a material that is not easily elastically deformed. In other words, the second elastic member 260 is formed of a material having a longitudinal elastic modulus (Young's modulus) larger than that of the elastic member 210. As a result, the second portion 200B as a whole is configured to be less deformable than the first portion 200A and the third portion 200C.

  In this embodiment, as shown in FIG. 8B, the second portion 200B is not easily deformed even if the seal member 200 tries to move outward when the developing roller 31 rotates. 200B can be supported and can prevent the first part 200A from falling outside due to the deformation. As a result, the adhesion between the inner end 201 and the inner contact surface 130 can be ensured, so that toner leakage can be further suppressed.

  In the present embodiment, since a plurality of slits 240 are formed side by side in the rotation axis direction, the seal member 200 can easily follow the surface shape of the roller body 31B. Adhesion can be increased. Thereby, toner leakage can be further suppressed.

  In the present embodiment, two slits 240 are formed. However, the present invention is not limited to this, and three or more slits may be formed as long as the sealing performance by the seal member can be ensured. Further, in the present embodiment, the second portion 200B has a configuration that is less likely to be deformed than the first portion 200A. However, in the present invention, the first portion and the second portion may have the same configuration.

[Fourth Embodiment]
Next, a fourth embodiment will be described.
As shown in FIG. 9, unlike the first embodiment, the seal member 200 does not include an adhesive member, includes an elastic member 210 and a contact member 220, and includes a slit 240. . The slit 240 of this embodiment has a depth from the contact surface 221 to the middle of the elastic member 210 (for example, about half the thickness of the elastic member 210).

  Also in this embodiment, since the seal member is not completely divided by the slit, the seal member 200 is not too small as in the case of the first embodiment or the second embodiment. Thus, the seal member 200 can be easily attached, and the developing cartridge 28 can be easily assembled.

  Although the embodiment has been described above, the present invention is not limited to the embodiment. About a concrete structure, it can change suitably in the range which does not deviate from the meaning of invention as follows.

  In the embodiment, the slit 240 is a cut formed in the seal member 200, but the present invention is not limited to this. For example, as shown in FIG. 10A, the slit 240 may be a long hole extending in the rotation direction of the developing roller 31 indicated by an arrow. The hole may be a through hole or a hole with a bottom. Further, as shown in FIG. 10B, the slit 240 is formed with a length from one end of the seal member 200 to the middle in the rotation direction, and is recessed from one end side to the other end side of the seal member 200. It may be a recess. The recess may have a bottom on the elastic member 210 side (the back side of the seal member 200). Although not shown in the drawings, the slit may be a recess having a length from one end to the other end of the seal member in the rotation direction and recessed from the contact member 220 side toward the elastic member 210 side. .

  In the embodiment, the seal member 200 is configured as one member. However, the present invention is not limited to this, and the seal member may be configured as another member, that is, as an individual seal member. For example, as shown in FIG. 11, the seal member 200 may be composed of a plurality of (two as an example in FIG. 11) seal constituent members 290 arranged as separate members arranged in the rotation axis direction. In this case, the slit 240 is formed between adjacent seal constituent members 290. In other words, the portion between the adjacent seal constituent members 290 becomes the slit 240. According to such a configuration, for example, by changing the material of the elastic member 210 and the contact member 220 of each seal component member 290, the seal component member 290 disposed inside and the seal component member disposed outside. The function of the printer can be made different from that of the printer 290, and a configuration that makes toner leakage more difficult can be realized.

  In the embodiment, the entire seal member 200 is bonded to the installation surface 120 of the frame 100. However, the present invention is not limited to this. For example, only a part of the seal member is bonded to the installation surface of the frame. May be. Further, in a configuration in which the seal member 200 is disposed in a state sandwiched between the inner contact surface 130 and the outer contact surface 140, the seal member may not be bonded to the installation surface of the frame. According to this, for example, the seal member can be easily attached to the frame as compared with the configuration in which the seal member is installed after the adhesive is applied to the installation surface. Can do. Moreover, the cost of the sealing member can be reduced as compared with the configuration in which the adhesive layer is provided on the sealing member.

  In the above-described embodiment, the frame 100 has the inner contact surface 130. However, the present invention is not limited to this. For example, the frame may have a configuration without the inner contact surface.

  In the embodiment, the outer contact surface 140 is a surface on the inner side in the rotation axis direction of the protrusion 102 provided on the side wall 101 of the frame 100, but is not limited thereto. For example, referring to FIG. 4, in a configuration in which the projecting portion 102 is not provided on the frame 100, the outer contact surface may be a surface on the inner side in the rotation axis direction of the side wall 101 of the frame 100. Moreover, in the said embodiment, although the flame | frame 100 had the outer side contact surface 140, it is not limited to this, For example, the structure which does not have an outer side contact surface may be sufficient.

  In the embodiment, the seal member 200 has a three-layer structure including the elastic member 210, the contact member 220, and the adhesive member 230, or a two-layer structure including the elastic member 210 and the contact member 220. However, the present invention is not limited to this. For example, the seal member may have a single layer structure or a multilayer structure of four or more layers. Moreover, in the said embodiment, although the contact member 220 was formed from cloth materials, such as a mesh and felt, it is not limited to this, For example, a contact member may be formed from the resin film, the resin tape, etc. .

  In the embodiment, the developing cartridge 28 is exemplified as the developing device. However, the developing device 28 is not limited to this. For example, the developing device may further include a photosensitive drum, a charger, and the like. Specifically, the developing device may have the same configuration as the process cartridge 17 of the above embodiment. At this time, the developing cartridge and the drum unit may be configured to be detachable or may be configured integrally. In addition, the developing cartridge as the developing device may be configured such that a portion where the developing roller and the layer thickness regulating blade are disposed and a storage portion (toner box) for storing the toner are detachable.

  In the above embodiment, the laser printer 1 capable of forming only a monochrome image is exemplified as an image forming apparatus in which the developing device of the present invention is used. However, the present invention is not limited to this, and for example, a printer capable of forming a color image. There may be. The image forming apparatus is not limited to a printer, and may be, for example, a copier or a multi-function machine including a document reading apparatus such as a flat bed scanner.

28 Developing cartridge 31 Developing roller 31B Roller body 31E End 100 Frame 120 Installation surface 130 Inner contact surface 140 Outer contact surface 200 Seal member 201 Inner end 202 Outer end 210 Elastic member 220 Contact member 221 Contact surface 230 Adhesive member 240 Slit

Claims (8)

A developing roller having a roller body configured to carry a developer;
A frame that rotatably supports the developing roller;
An elastically deformable seal member disposed between both ends of the roller body and the frame;
The seal member has an outer end of the seal member positioned outside an end of the roller body in the rotation axis direction in the rotation axis direction of the developing roller,
The seal member has a slit extending in a rotation direction of the developing roller on a contact surface in contact with the roller body,
The slit is positioned inward of the end of the roller body in the rotational axis direction in the rotational axis direction ,
The seal member is a first portion disposed on the innermost side in the rotation axis direction, that is, a first portion having a first elastic member, and a second portion disposed outside the first portion. A second portion having a second elastic member, and a third portion having a third elastic member, which is a third portion arranged outside the second portion,
The slit is formed between the first portion and the two portions, and between the second portion and the third portion,
The second elastic member is harder than the first elastic member and the third elastic member,
The developing device according to claim 1, wherein an end portion of the roller body in the rotation axis direction is in contact with the third portion .   The developing device according to claim 1, wherein the frame has an inner contact surface that contacts an inner end of the seal member in the rotation axis direction. Before SL slit developing device according to claim 1 or claim 2, characterized in that it has a depth from the contact surface to the middle of the second elastic member. The sealing member is pre-Symbol first elastic member, the second elastic member and the third elastic member has a bonding member for bonding to the frame,
The developing device according to claim 1, wherein the slit has a depth from the contact surface to the middle of the adhesive member.   5. The developing device according to claim 1, wherein the slit has a length from one end of the seal member to the middle in the rotation direction. 6. The sealing member includes a contact member in contact with the front Symbol roller body,
The developing device according to claim 1, wherein the contact member is a cloth material. The seal member is composed of a plurality of seal constituent members arranged as separate members arranged in the rotation axis direction,
The developing device according to claim 1, wherein the slit is formed between adjacent seal constituent members. The cloth material has elasticity in a predetermined direction,
The developing device according to claim 6, wherein the contact member is formed so that an expansion / contraction direction of the cloth material is along the rotation axis direction.

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