JP5370922B2 - Developing device, process unit, image forming apparatus, and assembling method of developing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developing device capable of improving assemblability and removability of a sealing member when the device is used, and also making the device small in size and low in cost. <P>SOLUTION: The developing device includes: a developer carrier 34 on which developer is carried; a developing housing 32 to which the developer carrier 34 is attached and inside which the developer is contained; and the sealing member 50 which seals space between the surface of the developer carrier 34 and opposed parts 321 and 322 of the developing housing 32 disposed through a gap relative to the surface of the developer carrier 34 when the device is not used. The sealing member 50 is wound around the surface of the developer carrier 34. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a developing device, a process unit including the developing device, an image forming apparatus, and a method for assembling the developing device.

  In an image forming apparatus such as a copying machine, a printer, a facsimile machine, or a complex machine of these, it is widely performed that a developer is enclosed in a developing device in advance at the time of shipment from a factory and then incorporated into the image forming device. In such a developing device, generally, a sealing member is provided so that the developer does not leak from a gap between the developing housing containing the developer and the developing roller attached thereto.

  For example, as shown in FIG. 15, the developing device described in Patent Document 1 includes an internal space 100 a in which the developing roller 200 is mounted and an internal space portion 100 b (developer storage portion) that stores a developer. Are separated from each other by the sheet material 300 to prevent the developer from leaking from the opening (the internal space 100a side) of the developing housing 100.

  Further, as shown in FIG. 16, the developing device described in Patent Document 2 seals between the developing roller 200 and the opening of the developing housing 100 by an elastic body 400, and the thickness of the toner by the sheet material 600. The gap between the regulating member 500 that regulates the height and the developing roller 200 is sealed.

  Further, the user who has received the image forming apparatus starts using the image forming apparatus after pulling out the sealing member sandwiched between the developing devices.

  In the developing device shown in FIG. 15, a two-component developer composed of toner and carrier is used as the developer. In this case, the developer is supplied to the developing roller 200 by the conveying screw 700 that rotates, and after the toner of the developer is consumed by image formation, the developer is returned to the developer container 100b. Then, the returned developer is supplied again to the developing roller 200 by the conveying screw 700. As described above, the developer is repeatedly supplied to the developing roller 200 while being conveyed by the conveying screw 700. For this reason, the amount of toner in the developer decreases as it goes downstream in the transport direction, and the image density tends to be different between the upstream side and the downstream side in the transport direction (or both ends in the longitudinal direction of the developing roller). There is.

  In order to solve the above problem, a developing device as shown in FIG. 17 has been proposed in recent years. In the developing device shown in FIG. 17, a supply path 100 c for supplying the developer to the developing roller 200 and a recovery path 100 d for recovering the developer after being supplied to the developing roller 200 are formed in the housing 100. The supply path 100c and the recovery path 100d are provided with screws 800 and 900 for conveying the developer, respectively. In this developing device, the developer once supplied to the developing roller 200 from the supply path 100c is recovered to the recovery path 100d. Therefore, unlike the developing device shown in FIG. 15, the developer after the toner is consumed is not repeatedly used, so that it is possible to suppress a difference in image density at both ends in the longitudinal direction of the developing roller.

  However, in order to prevent developer leakage in the developing device shown in FIG. 17, for example, when the developing device sealing technique shown in FIG. 15 is employed, each of the opening of the supply path 100c and the opening of the recovery path 100d is provided. It is necessary to seal with another sheet material. Thus, providing two or more sheet materials for sealing leads to a decrease in the assemblability of the developing device and the sheet material removability during use, an increase in the size of the device, and an increase in cost. Further, the developing apparatus shown in FIG. 16 has the same problem because it uses at least two sealing members.

  SUMMARY OF THE INVENTION In view of such circumstances, the present invention improves the assemblability and the removability of the sealing member at the time of use, and develops a device capable of reducing the size and cost of the device. And an assembling method of the developing device.

According to the first aspect of the present invention, there is provided a developer carrying member carrying a developer, a developing housing in which the developer carrying member is mounted and containing the developer, and a developer carrying member carried on the surface of the developer carrying member. A sealing member that seals between the regulating member that regulates the thickness of the developer and the surface of the developer carrying member and the facing portion of the developing housing that is disposed with a clearance from the surface when not in use. In the developing device provided with the stop member, the sealing member has a through-hole exposing a part of the surface of the developer carrier, and the development is performed by winding the sealing member around the surface of the developer carrier. With the developer carrier mounted on the developing housing, the sealing member seals between the surface of the developer carrier and the opposing portion of the regulating member disposed with a gap with respect to the surface. And the through hole is opposed to the opposing portion of the restricting member. It is obtained by movable in the position not opposed from the position.

In a state where the through hole of the sealing member is disposed at a position facing the facing portion of the regulating member, the surface of the developer carrying member exposed from the through hole and the facing portion of the regulating member face each other. In this state, the gap between the developer carrying member and the regulating member can be adjusted by bringing the gap adjusting member into contact with the exposed surface of the developer carrying member and the opposing portion of the regulating member. Thus, according to the first aspect of the present invention, the gap adjusting member can be brought into direct contact with the developer carrier and the regulating member in a state where the sealing member is wound around the developer carrier. It is possible to adjust the gap between them with high accuracy. After adjusting the gap between the developer carrier and the regulating member, the gap between the developer carrier and the regulating member is sealed by moving the through hole to a position not facing the regulating member. It can be easily sealed with a member, and leakage of the developer can be prevented.

Wherein the invention of claim 2, in the developing device according to claim 1, by winding the sealing member with a gap relative to the surface of said developer carrying member, said sealing member and said developer housing It is comprised so that it may contact with respect to each opposing part of a control member .

  By doing in this way, even if the sealing member is comprised by the member thinner than the clearance gap between the surface of a developing agent carrier and an opposing part, a sealing member can be made to contact an opposing part and can be sealed.

According to a third aspect of the present invention, in the developing device according to the first or second aspect , a contact portion is provided for abutting one end portion of the sealing member wound around the surface of the developer carrying member. Displace the sealing member in the direction away from the surface of the developer carrying member by displacing the sealing member in the direction opposite to the winding direction by bending the sealing member by bringing one end of the sealing member into contact with the portion. Thus, the sealing member is configured to come into contact with the opposing portions of the developing housing and the regulating member .

  By doing in this way, even if the sealing member is comprised by the member thinner than the clearance gap between the surface of a developing agent carrier and an opposing part, a sealing member can be made to contact an opposing part and can be sealed. In addition, in this case, the force due to the deflection propagates to the winding portion of the sealing member and displaces the sealing member in the direction away from the surface of the image carrier, so that the sealing member contacts the facing portion. Therefore, the sealing force can be improved.

According to a fourth aspect of the present invention, in the developing device according to the first or second aspect , the sealing member is wound around the surface of the developer carrying member at least once, and a portion where the sealing member overlaps has peelability. Bonded with an adhesive.

  By adhering the overlapping portion of the sealing member with an adhesive, it is possible to prevent the sealing member from being separated from the developer carrier during assembly of the developing device, and the assembling workability is improved. In addition, by using an adhesive having releasability, the adhesive portion of the sealing member can be easily peeled off and the sealing member can be separated from the developer carrying member.

According to a fifth aspect of the present invention, in the developing device according to the fourth aspect of the present invention, the sealing member is bonded at one location by the adhesive.

  By performing the bonding of the sealing member at one place, good peelability can be ensured.

According to a sixth aspect of the present invention, there is provided the developing device according to any one of the first to fifth aspects, wherein the developer carrying member around which the sealing member is wound is attached to the developing housing from the developing housing. An exposed gripping part is provided on the sealing member.

  By grasping and pulling the grip portion exposed from the developing housing, the sealing member can be easily separated from the developer carrier.

According to a seventh aspect of the present invention, in the process unit comprising at least a latent image carrier that carries a latent image and a developing device that supplies a developer to the latent image on the latent image carrier and develops the developing device, the developing device The developing device according to any one of claims 1 to 6 is provided.

Since the process unit includes the developing device according to any one of claims 1 to 6 , the above-described effects by these developing devices can be obtained.

An eighth aspect of the invention is an image forming apparatus including the developing device according to any one of the first to sixth aspects or the process unit according to the seventh aspect .

Since the image forming apparatus includes the developing device according to any one of claims 1 to 6 or the process unit according to claim 7 , the above-described effects by these developing device or process unit can be obtained. .

The invention of claim 9 includes a step of winding a sealing member around the surface of the developer carrying member carrying the developer, and exposing a part of the surface of the developer carrying member from a through hole provided in the sealing member. A step of attaching a regulating member that regulates the thickness of the developer carried on the surface of the developer carrying body to a developing housing that can accommodate the developer inside, and the developer carrying around the sealing member The sealing member is interposed between the surface of the developer carrying member and the facing portions of the developing housing and the regulating member that are disposed with a gap with respect to the surface of the developer carrying member. And the gap adjustment member is applied to the surface of the developer carrying member exposed from the through hole and the facing portion of the regulating member. The surface of the developer carrying member in contact with A developing device including a step of adjusting a gap between the facing portion of the restricting member and a step of moving the through hole from a position facing the facing portion of the restricting member to a position not facing after adjusting the gap. This is an assembly method.

  By this method, it is possible to easily seal between the surface of the developer carrying member and the facing portion of the developing housing with one sealing member, and it is possible to prevent the leakage of the developer. In addition, by disposing the through hole of the sealing member at a position facing the opposing portion of the regulating member, the current gap adjusting member is exposed from the image carrier with the sealing member wound around the developer carrier. The surface and the regulating member can be brought into direct contact, and the gap between the developer carrier and the regulating member can be adjusted with high accuracy. In addition, after adjusting the gap between the developer carrier and the regulating member, the through hole of the sealing member is moved to a position not facing the regulating member, so that the gap between the developer carrier and the regulating member is The gap can be sealed with a sealing member, and leakage of the developer can be prevented.

The invention of claim 10, in the assembling method of the developing apparatus according to claim 9, after the developer carrying member wound with the sealing member is mounted to the developing housing, the one end portion of said sealing member, The sealing member is displaced in the direction opposite to the winding direction and developed by causing the sealing member to bend by being brought into contact with an abutting portion provided in the developing housing or the photoreceptor housing assembled to the developing housing. The seal member is displaced in a direction away from the surface of the agent carrier, and the sealing member is brought into contact with the opposing portions of the developing housing and the regulating member .

  By doing in this way, even if the sealing member is comprised by the member thinner than the clearance gap between the surface of a developing agent carrier and an opposing part, a sealing member can be made to contact an opposing part and can be sealed. In addition, in this case, the force due to the deflection propagates to the winding portion of the sealing member and displaces the sealing member in the direction away from the surface of the image carrier, so that the sealing member contacts the facing portion. Therefore, the sealing force can be improved.

  According to the present invention, since the gap existing around the developer carrier can be sealed by one sealing member, there is no need to provide a plurality of sealing members. For this reason, it is possible to reduce the assembly cost and the number of assembly steps, and to reduce the size of the apparatus. Moreover, the removal work of the sealing member by a service person, a user, etc. becomes easy.

1 is an external perspective view of an image forming apparatus to which an embodiment of the present invention is applied. 2 is a schematic longitudinal sectional view illustrating an example of an internal configuration of the image forming apparatus. FIG. 2 is a schematic cross-sectional view of a process unit mounted on the image forming apparatus. FIG. It is a perspective view which shows the state which expand | deployed the sealing member which concerns on this invention. It is a perspective view which shows the state which wound the said sealing member around the developing roller. It is a figure for demonstrating the method of winding the said sealing member around a developing roller, Comprising: (a) is a figure which shows the state which attached | subjected the adhesive agent to the sealing member, (b) is a developing roller on a sealing member. The figure which shows the state which set | placed, (c) is a figure which shows the state in the middle of winding a sealing member around a developing roller. FIG. 6 is a diagram illustrating a state before the developing roller is mounted on the developing housing. FIG. 7 is a diagram illustrating a state where the developing roller is mounted on the developing housing. FIG. 6 is a cross-sectional view of a state where the developing roller is mounted on the developing housing. It is a figure which shows the state which inserted the clearance gap adjustment member between the developing roller and the doctor blade. It is a figure which shows the state which rotated the sealing member and changed the position. FIG. 6 is a diagram illustrating a state before the photoreceptor housing and the development housing are assembled. FIG. 3 is a cross-sectional view of a state in which a photoconductor housing and a development housing are assembled. FIG. 2 is a diagram illustrating a state where an upper cover of the image forming apparatus is opened. It is a schematic sectional drawing of the conventional image development apparatus. It is a schematic sectional drawing of another conventional developing device. It is a schematic sectional drawing of another conventional developing device.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the embodiments and modifications, components such as members and components having the same function or shape are denoted by the same reference numerals as much as possible, and once described, the description thereof is omitted.

  First, with reference to FIG. 1 and FIG. 2, the operation of the image forming apparatus to which the embodiment of the present invention is applied and the operation thereof will be described. FIG. 1 is an external perspective view of an image forming apparatus to which an embodiment of the present invention is applied, and FIG. 2 is a schematic longitudinal sectional view showing an example of an internal configuration of the image forming apparatus. The image forming apparatus shown in both figures is a tandem type color image forming apparatus.

  The image forming apparatus shown in FIG. 1 and FIG. 2 is disposed almost at the center of the apparatus main body 1 and includes an image forming unit 2 provided with an image forming unit (to be described later) that forms an image on a sheet, and below the image forming unit 2. And a sheet feeding unit 20 that feeds a sheet or a sheet S as an example of a sheet-like recording medium to the image forming unit 2, and a sheet on which an image is formed by the image forming unit 2 (both A sheet discharge unit 25 serving as a sheet discharge unit that discharges from the front right side of the drawing and the front side of the apparatus to the back side (the rear left side of both drawings and the back side of the apparatus), and the image forming unit 2 And a sheet stacking unit 40 on which sheets discharged from the sheet discharge unit 25 are stacked. Here, the sheet is, for example, paper such as transfer paper or recording paper (including thick paper, postcard, envelope, plain paper, thin paper, etc.), coated paper (including coated paper, art paper, etc.), OHP sheet or OHP. It means an image forming medium capable of transferring an image, including film, tracing paper and the like. The image forming unit 2 is also referred to as an image recording unit 2 that records an image on the paper S, and the sheet stacking unit 40 is also referred to as a sheet mounting unit 40 that mounts and stacks discharged sheets.

  As shown in FIG. 2, the image forming unit 2 includes a plurality of drum-shaped photoconductors 3a, 3b, 3c, and 3d configured as an image carrier or a latent image carrier, and each of the photoconductors 3a to 3d. In 3d, toner images of different colors are formed. In the illustrated example, a yellow toner image, a cyan toner image, a magenta toner image, and a black toner image are formed on the surfaces of the photoreceptors 3a to 3d, respectively. The photoconductors 3a to 3d are arranged in parallel with each other at a predetermined interval, and an intermediate transfer belt 4 configured as an intermediate transfer body is arranged facing the lower portions of the photoconductors 3a to 3d. As the image carrier / intermediate transfer member, a drum can be used. However, in the illustrated example, the drum is wound around a plurality of support rollers 5 and 6 and is driven in an arrow direction (counterclockwise in FIG. 2). An intermediate transfer belt 4 composed of a belt is used.

  Since the configuration around each of the photoconductors 3a to 3d is the same, the photoconductor 3a on which the yellow toner image arranged on the rightmost side in FIG. 2 is formed will be described as a representative. That is, the photosensitive member 3a is charged with a charging roller 7 as a charging unit that performs uniform charging on the surface of the photosensitive member 3a, and the surface of the photosensitive member 3a is irradiated with laser light based on image information, thereby electrostatic latent. An optical scanning device (LSU) 8 that forms an image, a developing device 9 that visualizes an electrostatic latent image formed on the surface of the photoconductor 3 a, and a photoconductor 3 a that are disposed opposite to each other via an intermediate transfer belt 4. The transfer device 10 and a cleaning blade 11 as a cleaning unit for removing toner remaining on the surface of the photoreceptor 3a after being transferred to the intermediate transfer belt 4 are provided in this order. Above the developing device 9, a cylindrical toner container and a replenishing mechanism are arranged, and the replenishing mechanism is driven according to toner consumption in the developing device 9 to supply toner from the toner container to the developing device.

  When image formation is started in such an image forming apparatus, the photosensitive member 3a is rotated in the clockwise direction in FIG. 2, and at this time, the surface of the photosensitive member 3 is uniformly charged to a predetermined polarity by the charging roller 7. . Next, the charged surface is irradiated with laser light based on image information from the optical scanning device 8, thereby forming an electrostatic latent image on the photoreceptor 3 a. The electrostatic latent image formed on the surface of the photoreceptor 3 a is visualized as a yellow toner image by the developing device 9, and the yellow toner image is transferred onto the intermediate transfer belt 4 by the transfer device 10.

  At the time of full color image formation, the above-described image forming operation is performed in the same manner on all the remaining photoconductors 3b to 3d, whereby yellow toner images, cyan toner images, and magenta toner images respectively formed on the respective photoconductors 3a to 3d. Then, the black toner image is sequentially transferred onto the intermediate transfer belt 4 in a superimposed manner. In the image forming apparatus, a secondary transfer roller 12 is disposed so as to face the support roller 6 with the intermediate transfer belt 4 interposed therebetween.

  On the other hand, a paper feed unit 20 disposed below the image forming unit 2 includes a paper feed tray 21 as a sheet storage unit on which sheets S as sheets made of transfer paper, recording paper, resin film, and the like are stacked, A paper feed roller 22 that feeds the paper S stacked on the paper feed tray 21 and a friction pad 23 as a separating unit that separates the multi-feed paper into one sheet are provided.

  The sheet S fed from the sheet feeding unit 20 is sent out toward the registration roller 13 and is once abutted against the registration roller 13 whose leading end is stopped. As a result, after the oblique deviation of the leading edge of the sheet S is corrected and aligned, the registration roller 13 causes the color toner image formed on the intermediate transfer belt 4 to be printed on the secondary transfer portion provided with the secondary transfer roller 12. The rotation is resumed at a predetermined timing so as to coincide with the leading end portion of S, and the sheet S is sent out toward the secondary transfer portion including the secondary transfer roller 12.

  The sheet S on which the unfixed color toner image is transferred in the secondary transfer unit is sent to the fixing unit 14 which is a fixing device, and after the unfixed color toner image is fixed by heating and pressing by the fixing unit 14. The sheet discharge roller pair 25a and 25b of the sheet discharge unit 25 discharges and discharges the image surface downward (face down) onto the sheet stacking unit 40 provided on the upper surface of the apparatus main body 1. The fixing unit (fixing device) 14 includes a fixing roller 14a, a fixing belt 14c wound around the fixing roller 14a, and a pressure roller 14b press-contacting the fixing roller 14a via the fixing belt 14c. The fixing unit 14 is not limited to the above-described one, and a roller type having a built-in heater and a heating method adopting IH can be appropriately employed. The transfer residual toner and the like adhering to the surface of the intermediate transfer belt 4 after the color toner image transfer is removed by the belt cleaning device 15 to prepare for the next image forming / transfer process.

  An upper cover 18 serving as an upper cover member that covers the image forming unit 2 is provided on the upper portion of the apparatus main body 1, and an upper surface portion of the upper cover 18 is used as a sheet discharge tray (sheet stacking unit) of the sheet stacking unit 40. Surface) 41. A support portion is not provided on the rear end side of the upper cover 18. With this configuration, even if a long sheet is longer than the width in the front-rear direction of the paper discharge tray 41 of the upper cover 18, a part of the long sheet is hung to the rear side beyond the paper discharge tray 41 so that the long sheet can be stocked without any problem. can do.

  Further, as shown in FIG. 2, the upper cover 18 supports an optical scanning device 8 which is a part of the image forming unit (image forming means) 2 at a lower portion thereof, and is a hinge provided on the rear end side of the device. 17 is configured to be openable upward. The upper cover 18 is locked to the apparatus main body 1 by a lock lever 60 serving as a locking means, which will be described later. Although not shown, when the upper cover 18 is swung and opened counterclockwise, the lower optical scanning device 8 is swung up together, and the image forming unit can be accessed for maintenance. Etc. can be easily performed. Further, in this example, the photosensitive member 3a to 3d of the image forming unit 2 from the part where the upper cover 18 is opened, and the charging roller 7, the developing device 9 and the cleaning device 11 respectively arranged around these are integrated. The process unit can be removed and installed for replacement.

  When the upper cover 18 is swung and released, the upper end of the sheet discharge tray 41 is swung up so that the rear end of the sheet discharge tray 41 faces down. If it is moved or released, there is a problem that the stocked sheet falls to the rear side of the apparatus. That is, if the user forgets to remove the stock sheet S and rotates the upper cover 18, the problem arises that the sheet S stocked on the paper discharge tray 41 falls to the back side of the apparatus main body 1. This problem can be solved by providing a support portion (not shown) also on the rear end side of the upper cover 18, but in the case of a long sheet, the rear end support portion is hit and the stock is disturbed.

  Therefore, in the present embodiment, the operation unit 61 that releases the lock of the lock lever 60 and makes the upper cover 18 swingable / openable is provided on the paper discharge tray 41 at a position hidden by the stocked sheets S. ing. The lock lever 60 is integrally provided with an operation portion 61 operated by a user on one end side and a lock claw 62 engaged with a protrusion 64 fixed to the apparatus main body 1 on the other end side. The lock lever 60 is rotatably supported around a pin 63 fixed to the upper cover 18, and the lock claw 62 is always engaged with the protrusion 64 by a torsion coil spring (not shown) mounted around the pin 63. A swinging urging force in the direction to match is applied. The operation unit 61 of the lock lever 60 is formed of a plate material having a surface that is on the same plane as the paper discharge tray 41, and the operation unit 61 can be put on the paper discharge tray 41. A fan-shaped recess 44 shown in FIG. 1 is formed.

  As described above, when the upper cover 18 is opened, a hand is inserted from the concave portion 44, and the operation portion 61 of the lock lever 60 is lifted up against the urging force of a torsion coil spring (not shown). The lock claw 62 is removed from the protrusion 64 by rotating clockwise around the pin 63. Then, the upper cover 18 is swung around the hinge 17 by lifting the operation unit 61 as it is.

  As described above, since the operation portion 61 of the lock lever 60 that allows the upper cover 18 to swing and open / close is disposed on the paper discharge tray 41 on which the sheet S is stocked, the sheet S is on the paper discharge tray 41. In this state, the upper cover 18 is reliably prevented from swinging and opening.

  FIG. 3 is a schematic cross-sectional view of a process unit provided with the respective photoreceptors 3a to 3d. Since the configuration of the four process units is the same, the configuration will be described in detail by taking the process unit arranged on the rightmost side in FIG. 2 as an example.

  As shown in FIG. 3, the process unit 30 includes a photoconductor housing 31 in which the photoconductor 3 a and the like are mounted, and a developing housing 32 in which various components constituting the developing device 9 are mounted. The photoconductor housing 31 and the developing housing 32 are configured to be assembled and separated. Further, a laser beam path space 33 through which the laser beam irradiated from the optical scanning device 8 shown in FIG. 1 to the photosensitive member 3a is formed between the photosensitive member housing 31 and the developing housing 32 assembled together.

  In addition to the photoreceptor 3a, the photoreceptor housing 31 is not shown with the charging roller 7, the charging roller cleaning member 26 for cleaning the surface of the charging roller, the cleaning blade 11, and the toner removed from the surface of the photoreceptor 3a by the cleaning blade 11 (not shown). A waste toner collecting screw 27, a lubricant 28, and a lubricant application brush 29 for scraping and applying the lubricant 28 to the surface of the photoreceptor 3a are mounted.

  On the other hand, the developing housing 32 has a developing roller 34 as a developer carrying member for carrying the developer on the surface, a supply screw 36 disposed in a supply passage 35 for supplying the developer, and a collection passage for collecting the developer. A recovery screw 38 disposed in 37, a doctor blade 39 as a regulating member for regulating the thickness of the developer carried on the surface of the developing roller 34, and a toner concentration sensor 42 for detecting the toner concentration are mounted. Yes. In the developing device of the present embodiment, a two-component developer composed of toner and carrier is used.

  The developer in the supply path 35 is conveyed by the supply screw 36, falls from the opening of the supply path 35, and is carried on the developing roller 34. The developer carried on the developing roller 34 is regulated to a predetermined thickness by passing through a predetermined gap between the doctor blade 39 and the surface of the developing roller 34. When the developer is conveyed to a position (photoconductor gap) between the developing roller 34 and the photoconductor 3a, the toner of the developer is electrostatically transferred to the photoconductor 3a, and the electrostatic charge on the photoconductor 3a. The latent image is developed. Thereafter, the developer on the developing roller 34 is collected in the collecting path 37. The developer recovered in the recovery path 37 is transported by the recovery screw 38 and accumulated downstream in the transport direction, and the deposited developer is transported again into the supply path 35 by transport means (not shown). In the supply path 35, toner is supplied from a toner supply unit (not shown) according to the amount of consumed toner. Further, the toner concentration of the developer in the collection path 37 is magnetically detected by the toner concentration sensor 42, and the toner concentration is adjusted based on the detection information.

  As described above, in the developing device of this embodiment, the developer that has been supplied to the developing roller and consumed the toner is temporarily collected without being repeatedly supplied to the developing roller as it is, and then the toner is replenished. That is, since an unused developer is supplied to the developing roller or a developer replenished with toner after use is supplied, unlike the developing device described in Patent Document 1 shown in FIG. It is possible to suppress a difference in image density at both ends in the longitudinal direction of the developing roller.

Hereinafter, the sealing member which is a characteristic part of the present invention will be described.
FIG. 4 is a perspective view showing a state in which the sealing member 50 is developed, and FIG. 5 is a perspective view showing a state in which the sealing member 50 is wound around the developing roller 34.

  As shown in FIG. 4, the sealing member 50 is configured by a substantially rectangular sheet material. As the sheet material, paper having a thickness of about 0.1 mm to 0.2 mm, Mylar having a thickness of 0.2 mm or less, or the like is used. However, the sealing member 50 is not limited to these, and sheet materials other than paper and mylar can be used as the sealing member. A through hole 51 is formed in the sealing member 50. In the present embodiment, three through holes 51 are formed, but at least one through hole 51 may be formed. A convex grip 52 is provided at an intermediate portion at one end of the sealing member 50.

  In order to wrap the sealing member 50 around the developing roller 34, first, as shown in FIG. 6A, the back surface of the sealing member 50 on the side opposite to the end portion provided with the grip portion 52 ( An adhesive 53 having peelability is applied to the lower surface in the drawing. Next, as shown in FIG. 6 (b), the developing roller 34 is placed on the sealing member 50, and as shown in FIG. 6 (c), from the end of the sealing member 50 to which the adhesive 53 is applied. It is wound around the developing roller 34. Then, the sealing member 50 is wound around the developing roller 34 for at least one turn, and the surface to which the adhesive 53 is attached is overlapped and bonded to another surface to complete the winding of the sealing member 50.

  As shown in FIG. 5, when the winding of the sealing member 50 is completed, a part of the surface of the developing roller 34 is exposed through the through hole 51. In addition, the predetermined portion 54 including the grip portion 52 is not wound around the developing roller 34 in a state where the winding is completed. The non-winding portion 54 around which the sealing member 50 is not wound extends from the developing roller 34 in a tongue shape.

A method for assembling the developing device will be described with reference to FIGS.
FIG. 7 shows a state before the developing roller 34 is attached to the developing housing 32. In the state shown in FIG. 7, the developing housing 32 includes a supply screw 36 and a recovery screw 38. In addition, a doctor blade 39 is temporarily fixed by two screws 47 above the opening 320 of the developing housing 32 where the developing roller 34 is mounted. On the other hand, the sealing member 50 is wound around the developing roller 34 as described above.

  As shown in FIG. 7, the developing roller 34 is attached to the developing housing 32 with the non-winding portion 54 of the sealing member 50 facing the opposite side of the developing housing 32 and the through hole 51 of the sealing member 50. The developing roller 34 is fitted into the opening 320 of the developing housing 32 with the above facing upward. When the developing roller 34 is fitted into the opening 320, the through hole 51 is disposed so as to face the doctor blade 39. Alternatively, after the developing roller 34 is fitted into the opening 320, the sealing member 50 or the developing roller 34 may be rotated so that the through hole 51 faces the doctor blade 39.

  In FIG. 7, members 45 and 46 are support members for attaching and supporting the developing roller 34 to the developing housing 32. These support members 45 and 46 are respectively formed with one shaft insertion hole 450 and 460 through which the shaft 340 of the developing roller 34 is inserted, and two screw insertion holes 451 and 461 through which the mounting screw 48 is inserted. Yes. Then, after the developing roller 34 is fitted into the developing housing 32 as described above, both end portions of the shaft 340 of the developing roller 34 are inserted into the shaft insertion holes 450 and 460 of the respective support members 45 and 46, and each support is further supported. The screws 48 are inserted into the screw insertion holes 451 and 461 of the members 45 and 46 to fix the support members 45 and 46 to the developing housing 32 (see FIG. 8). As a result, the developing roller 34 is positioned with respect to the developing housing 32. A gear (not shown) for transmitting a driving force to the developing roller 34 is attached to the end of the shaft 340 where the developing roller 34 is exposed.

FIG. 9 is a cross-sectional view of the developing roller 34 attached to the developing housing 32.
As shown in FIG. 9, with the developing roller 34 fitted, a doctor is disposed between the facing portions 321 and 322 of the developing housing 32 facing the developing roller 34 and the surface of the developing roller 34, and the developing roller 34. There are predetermined gaps between the facing portion 390 of the blade 39 and the surface of the developing roller 34. Further, a sealing member 50 wound around the developing roller 34 exists in these gaps. However, the sealing member 50 is not interposed between the doctor blade 39 and the developing roller 34 at a position where the through hole 51 of the sealing member 50 faces the doctor blade 39. That is, the surface of the developing roller 34 exposed from the through hole 51 faces the doctor blade 39.

  As shown in FIG. 10, a gap adjusting member 49 (doctor gap adjusting member) is inserted between the surface of the developing roller 34 exposed from the through hole 51 and the doctor blade 39. Then, the screw 47 is tightened and fixed while the doctor blade 39 is abutted against the gap adjusting member 49. As a result, the doctor blade 39 is positioned, and the gap D (doctor gap) between the doctor blade 39 and the developing roller 34 is adjusted to a predetermined size. Thereafter, the gap adjusting member 49 is removed from between the developing roller 34 and the doctor blade 39.

  As described above, in the present invention, the gap adjusting member 49 can be brought into direct contact with the exposed surface of the developing roller 34 and the doctor blade 39 with the sealing member 50 wound around the developing roller 34. Thereby, the gap (doctor gap) between the developing roller 34 and the doctor blade 39 can be adjusted with high accuracy. Further, as shown in FIG. 9, the non-winding portion 54 of the sealing member 50 extends from a position opposite to the position near the doctor blade 39 of the developing roller 34. Is inserted between the developing roller 34 and the doctor blade 39 so that the non-wrapping portion 54 does not obstruct the insertion.

  After adjusting the gap D (doctor gap) between the doctor blade 39 and the developing roller 34, the sealing member 50 is rotated counterclockwise as shown in FIG. The blade 39 is moved from a position facing the blade 39 to a position not facing the blade 39. As a result, the sealing member 50 is interposed over the entire area where the facing portion 390 of the doctor blade 39 and the surface of the developing roller 34 face each other. Even after the sealing member 50 is rotated, the sealing member 50 is interposed between the facing portions 321 and 322 of the developing housing 32 and the surface of the developing roller 34.

  In this embodiment, as the sealing member 50, paper having a thickness of about 0.1 mm to 0.2 mm or mylar having a thickness of 0.2 mm or less is used. The gap between the doctor blade 39 and the developing roller 34 (doctor gap) is about 0.2 mm to 0.6 mm, and the gap between the developing housing 32 and the developing roller 34 is about 0.3 mm to 1 mm. Accordingly, although the paper and mylar used as the sealing member 50 are formed thinner than the gaps, the sealing member 50 is loosely wound around the developing roller 34 as shown in FIG. The stop member 50 can be brought into contact with the facing portion 390 of the doctor blade 39 and the facing portions 321 and 322 of the developing housing 32, and the gap can be sealed.

  As described above, between the developing roller 34 and the developing housing 32 and between the developing roller 34 and the doctor blade 39 are sealed with the sealing member 50, the developer is put into the developing housing 32. Fill. Specifically, the developer is filled from the hole 323 where the supply screw 36 is exposed and the hole 324 where the recovery screw 38 is exposed, of the developing housing 32 shown in FIG. Since these hole portions 323 and 324 are largely opened, the developer can be quickly filled, and the filling operation time can be shortened. In FIG. 8, a member denoted by reference numeral 55 is a support lid member that supports the supply screw 36 and the recovery screw 38 and closes the holes 323 and 324. The support lid member 55 is formed with two shaft insertion holes 550 and 551 through which the shafts of the supply screw 36 and the recovery screw 38 are inserted, and one screw insertion hole 552 through which the mounting screw 56 is inserted. . After the developer housing 32 is filled with the developer, the shafts of the supply screw 36 and the recovery screw 38 are inserted into the shaft insertion holes 550 and 551, and the screw 56 is inserted into the screw insertion hole 552, thereby supporting the cover member 55 is fixed to the developing housing 32. As a result, the supply screw 36 and the recovery screw 38 are supported, and the holes 323 and 324 are closed. Gears 57 and 58 for transmitting driving force are attached to the exposed shaft portions of the supply screw 36 and the recovery screw 38, respectively.

  As described above, the assembly of the developing device is completed. Further, in order to assemble the process unit, the photosensitive member housing is assembled to the developing housing of the developing device that has been assembled. As shown in FIG. 12, two ribs 310 each having a screw hole are provided at each of the front end portion and the rear end portion of the photoconductor housing 31 in the drawing. Further, an engaging portion 311 having a groove is provided at the end of the photoconductor housing 31 on the near side in the drawing. Further, the photoreceptor housing 31 before assembly includes the photoreceptor 3a, the charging roller 7, the charging roller cleaning member 26, the cleaning blade 11, the waste toner collecting screw 27, the lubricant 28, the lubricant application brush 29, and the like shown in FIG. The various members are already installed.

  Further, a concave portion 313 and contact portions 312 (convex portions) disposed on both sides of the concave portion 313 are provided on the upper portion of the photoconductor housing 31 in the figure. The concave portion 313 and the contact portion 312 are provided on the surface of the photosensitive member housing 31 that faces the developing housing 32 when the photosensitive member housing 31 and the developing housing 32 are assembled.

  When the photosensitive housing 31 and the developing housing 32 are assembled, the shaft 340 of the developing roller exposed from the developing housing 32 is engaged with the groove of the engaging portion 311 of the photosensitive housing 31 so that the rib Screws are attached to the screw holes 310 to fix the housings together. Further, when assembling the housings, the grip portion 52 of the sealing member 50 is disposed so as to be exposed upward from the concave portion 313 of the photosensitive member housing 31.

FIG. 13 is a cross-sectional view of the state in which the photoreceptor housing 31 and the development housing 32 are assembled.
As shown in FIG. 13, since the sealing member 50 is wound around the surface of the developing roller 34, when the housings are assembled, the sealing member 50 is sandwiched between the photoreceptor 3a and the developing roller 34. Can do. As a result, it is possible to prevent the development roller 34 from being damaged due to collision with the photoreceptor 3a during assembly. Further, in the present embodiment, the non-winding portion 54 of the sealing member 50 is extended from a position on the opposite side of the developing roller 34 from the position close to the doctor blade 39, so that the photosensitive member 3a and the developing roller The non-winding portion 54 can be interposed between the developing roller 34 and the developing roller 34 and the photosensitive member 3a, so that damage due to the collision between the developing roller 34 and the photosensitive member 3a can be prevented more reliably.

  As shown in FIG. 13, the non-wrapped portion 54 of the sealing member 50 is disposed so as to extend upward in the drawing through the laser optical path space 33 formed between the photosensitive member housing 31 and the developing housing 32. Is done. By disposing the non-winding portion 54 in this way, the grip portion 52 is exposed from the concave portion 313 (see FIG. 12) of the photoconductor housing 31. Further, an end portion 501 (see FIG. 12) excluding the grip portion 52 of the sealing member 50 is brought into contact with the contact portion 312 provided in the upper portion of the photoconductor housing 31 in the drawing.

  Further, when the sealing member is not bonded with an adhesive, it is possible to improve the sealing performance by the sealing member by bringing one end of the sealing member into contact with the contact portion 312 shown in FIG. is there. This will be described below.

  As shown in FIG. 13, when the non-winding portion 54 of the sealing member 50 is disposed so as to extend upward in the drawing, the end portion 501 (see FIG. 12) excluding the grip portion 52 of the sealing member 50 is applied. By bringing the contact portion 312 into contact with the lower surface of the figure, the non-winding portion 54 is disposed in a bent state. By bending the non-winding portion 54 in this way, the force due to the bending is propagated to the winding portion of the sealing member 50, and the sealing member 50 is displaced in the direction opposite to the winding direction. As a result, the sealing member 50 is displaced in a direction away from the surface of the developing roller 34, and the contact force of the sealing member 50 against the facing portions 321 and 322 of the developing housing 32 and the facing portion 390 of the doctor blade 39 is increased. As a result, the sealing performance between the developing roller 34 and each of the facing portions 321, 322, and 390 can be improved. Moreover, when Mylar whose stiffness (bending rigidity) is stronger than that of paper is used as the sealing member 50, the sealing performance can be further improved.

  Further, since the sealing member seals the periphery of the developing roller when not in use, the sealing member is removed by a service person, a user, or the like before using the image forming apparatus.

  In this embodiment, when removing the sealing member from the developing device, the upper cover 18 of the image forming apparatus is opened as shown in FIG. Then, by gripping and pulling the grip 52 (see FIG. 13) of the sealing member 50 exposed from the process unit, the adhesive member can be peeled off and the sealing member 50 can be removed.

  Moreover, it is also possible to perform adhesion | attachment of the sealing member by an adhesive agent in multiple places. However, in that case, the peelability is lowered, and when the sealing member is removed, the sealing member may be broken and remain in the process unit. On the other hand, when the sealing member is bonded with an adhesive at one location as in this embodiment, good peelability can be secured, and problems such as the sealing member being broken can be prevented. it can.

  As described above, according to the present invention, the gap (one or more) around the developing roller can be easily sealed by winding the sealing member around the developing roller. In addition, since it is not necessary to provide a plurality of sealing members, it is possible to seal with a single sealing member, so that it is possible to reduce the assembly cost and the number of assembly steps, and downsize the apparatus. Can be achieved. Moreover, the removal work of a sealing member can also be performed easily.

  The embodiment of the present invention has been described above, but the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the gist of the present invention. For example, as shown in FIG. 12 or FIG. 13, the abutting portion 312 that abuts the end portion of the sealing member 50 is provided in the photosensitive member housing 31, but a similar abutting portion is provided in the developing housing 32. It is also possible. Further, as shown in FIG. 14, the image forming apparatus of the above-described embodiment is configured to open the upper part and pull out the process unit upward. For example, the process unit is opened by opening the side surface of the image forming apparatus. The structure which pulls out to the side may be sufficient. In this case, the process unit is pulled out to the side, and the sealing member is pulled upward from the process unit. Further, the image forming apparatus according to the present invention is not limited to the color image forming apparatus shown in FIG. 1, but may be a monochrome image forming apparatus, other copiers, printers, facsimiles, or complex machines thereof. Good.

3a, 3b, 3c, 3d photoconductor (latent image carrier)
30 Process Unit 31 Photoreceptor Housing 32 Developer Housing 34 Developer Roller (Developer Carrier)
39 Doctor blade (regulating member)
49 Gap adjusting member 50 Sealing member 51 Through hole 52 Gripping part 53 Adhesive 312 Abutting part

JP 2005-189423 A JP-A-7-311536

Claims (10)

The developer carrying body carrying the developer, the developing housing in which the developer carrying body is mounted and containing the developer, and the thickness of the developer carried on the surface of the developer carrying body are regulated. And a developing device comprising: a sealing member that seals between the regulating member to be used and the surface of the developer carrying member and the facing portion of the developing housing disposed with a gap with respect to the surface when not in use In
The sealing member has a through hole exposing a part of the surface of the developer carrying member,
In a state where the sealing member is wound around the surface of the developer carrying member and the developer carrying member is mounted on the developing housing, the surface of the developer carrying member and the surface thereof are disposed with a gap therebetween. The space between the opposing portions of the restricting member is sealed with the sealing member, and the through hole is configured to be movable from a position facing the facing portion of the restricting member to a position not facing. Developing device. The said sealing member is comprised so that the said sealing member may be made to contact with each opposing part of the said developing housing and the said control member by winding with a space | interval with respect to the surface of the said developer carrier. 2. The developing device according to 1. An abutting portion is provided for abutting one end of the sealing member wound around the surface of the developer carrying member, and the sealing member is bent by abutting the one end of the sealing member on the abutting portion. Accordingly, the sealing member is displaced in a direction opposite to the winding direction and is displaced in a direction away from the surface of the developer carrying member, so that the sealing member is placed on each facing portion of the developing housing and the regulating member. The developing device according to claim 1, wherein the developing device is configured to contact with each other . The developing device according to claim 1 , wherein the sealing member is wound around the surface of the developer carrying member at least once, and a portion where the sealing member overlaps is adhered with an adhesive having peelability . The developing device according to claim 4 , wherein the sealing member is bonded to the adhesive at a single location . Wherein said developer carrying body wrapped sealing member being attached to the developing housing, wherein the grip portion exposed from the developing housing to any one of claims 1 to 5 which is provided on the sealing member Development device. In a process unit comprising at least a latent image carrier that carries a latent image and a developing device that supplies a developer to the latent image on the latent image carrier and develops the latent image,
A process unit comprising the developing device according to claim 1 as the developing device. An image forming apparatus comprising the developing device according to claim 1 or the process unit according to claim 7. Winding a sealing member around the surface of the developer carrying member carrying the developer, and exposing a part of the surface of the developer carrying member from a through hole provided in the sealing member;
Attaching a regulating member for regulating the thickness of the developer carried on the surface of the developer carrying body to a development housing capable of accommodating the developer inside;
The developer carrying member around which the sealing member is wound is mounted on the developing housing, and the surface of the developer carrying member and each of the developing housing and the regulating member that are disposed with a gap with respect to the surface of the developer carrying member. Interposing the sealing member between the parts,
The through hole is disposed opposite to the facing portion of the restricting member, and a gap adjusting member is brought into contact with the surface of the developer carrying member exposed from the through hole and the facing portion of the restricting member. Adjusting the gap between the surface of the developer carrier and the facing portion of the regulating member;
And a step of moving the through hole from a position facing the facing portion of the restricting member to a position not facing after adjusting the gap. After the developer carrying member around which the sealing member is wound is mounted on the developing housing, one end portion of the sealing member is provided on the developing housing or the photoreceptor housing assembled to the developing housing. The sealing member is deflected by contacting the sealing member, thereby displacing the sealing member in a direction opposite to the winding direction and in a direction away from the surface of the developer carrying member, thereby The method for assembling the developing device according to claim 9, wherein the housing is in contact with each facing portion of the regulating member.

Images