JP4944481B2 - Developing device, process cartridge, and electrophotographic image forming apparatus - Google Patents

Description

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

Here, the electrophotographic image forming apparatus forms an image on a recording medium (for example, recording paper, OHP sheet, etc.) using an electrophotographic image forming process.
Examples of the electrophotographic image forming apparatus include an electrophotographic copying machine, an electrophotographic printer (for example, a laser printer, an LED printer, etc.), a facsimile apparatus, a word processor, and a multifunction machine (multifunction printer) thereof.

  The process cartridge is a cartridge in which at least the developing means as the process means and the electrophotographic photosensitive member are integrally formed so as to be detachable from the main body of the electrophotographic image forming apparatus.

  The developing device includes a developer storage frame that stores a developer, a developer carrier, and a development frame that holds the developer carrier, and is used in an electrophotographic image forming apparatus. Is.

  In an electrophotographic image forming apparatus using an electrophotographic image forming process, image information is recorded on an outer peripheral surface (surface) of a drum-shaped electrophotographic photosensitive member (hereinafter referred to as a photosensitive drum) uniformly charged by a charging unit. An electrostatic latent image is formed by performing appropriate selective exposure. The latent image is developed with toner (developer) by a developer carrying member to obtain a toner image (developed image). Next, the toner image is transferred to a recording medium, and heat and pressure are applied to the toner image to fix the toner image on the recording medium, thereby forming an image on the recording medium. Residual toner remaining on the surface of the photosensitive drum after the transfer of the toner image is removed by a cleaning unit, and the photosensitive drum cleaned by the cleaning unit is used for the next image formation.

  Some process cartridges are configured by integrally combining a developing unit (developing apparatus) and a photosensitive unit. The developing unit is configured by integrally assembling a toner storage frame that stores toner and a development frame that holds a developing roller (developer carrier). The photosensitive unit is configured by holding a photosensitive drum, a charging unit, and a cleaning unit on a cleaning frame. The cartridge is configured by integrally coupling the developing frame of the developing unit and the cleaning frame of the photosensitive unit.

As a developing unit, there is a developing unit that supports a developing frame so as to be movable with respect to a toner storage frame (Patent Document 1). In this developing unit, the developing roller is pressed toward the photosensitive drum in a state where a spacer roller provided at both ends is brought into contact with the surface of the photosensitive drum and a certain gap is maintained between the developing roller. Further, in order to prevent the toner from leaking between the developing frame and the toner storage frame, the space between the developing frame and the toner storage frame is sealed with foamed polyurethane.
JP 2000-76144 A

  However, in order to reliably seal the toner in the above prior art, it is necessary to greatly compress the foamed polyurethane, and there is a possibility that the force urged from the toner storage frame to the development frame is increased. Thereby, there is a possibility that the force pressed from the developing roller to the photosensitive drum becomes larger than necessary.

  Accordingly, an object of the present invention is to suppress the force urged from the first frame containing the developer to the second frame holding the developer carrying member while suppressing the first frame and the first frame. An object of the present invention is to provide a developing device capable of sealing between the two frames.

  Another object of the present invention is to suppress the force applied from the first frame containing the developer to the second frame holding the developer carrying member while suppressing the force applied to the first frame. An object of the present invention is to provide a process cartridge capable of sealing between the second frame body.

  Another object of the present invention is to provide an electrophotographic image forming apparatus to which the above process cartridge can be attached and detached.

A typical means in the present invention for solving the above problems is a developing device used in an electrophotographic image forming apparatus for forming an image on a recording medium,
A developer carrier for developing a latent image formed on the electrophotographic photosensitive member using a developer;
A first frame for storing the developer, the first frame having a first opening for supplying the developer and a first coupling portion provided around the first opening. Body,
A second frame having the developer carrier, a second opening for receiving the supply of the developer from the first opening, and a second coupling portion provided around the second opening; ,
A sheet-like elastic member provided in one of the first coupling portion and the second coupling portion, and the first frame and the first frame in a state where the first opening and the second opening are opposed to each other. The first coupling portion and the second coupling portion so that the developer can be moved and the developer leaks between the first coupling portion and the second coupling portion. An elastomer that binds either the other of the two coupling portions and the elastic member;
An urging member provided on the one side, wherein the urging member urges the elastic member toward a step generated in the elastomer;
It is characterized by having.

According to the present invention, the first frame and the second frame are suppressed while suppressing the force applied from the first frame containing the developer to the second frame holding the developer carrier. It is possible to provide a developing device, a process cartridge, and an electrophotographic image forming apparatus in which the process cartridge can be attached to and detached from the frame body .

  Hereinafter, the present invention will be described in detail with reference to the drawings.

(1) Overall Configuration of Electrophotographic Image Forming Apparatus FIG. 2 is a structural model diagram of an example of an electrophotographic image forming apparatus. This electrophotographic image forming apparatus (hereinafter referred to as an image forming apparatus) is a laser printer that forms an image on a recording medium (for example, recording paper, OHP sheet, cloth, etc.) using an electrophotographic process.

  In the image forming apparatus, a drum-shaped electrophotographic photosensitive member (hereinafter referred to as “photosensitive drum”) 10 is rotated in a direction indicated by an arrow at a predetermined peripheral speed (process speed). The outer peripheral surface (surface) of the photosensitive drum 10 is uniformly charged by the charging means 11. An electrostatic latent image is formed by irradiating the charged surface with laser light L corresponding to image information from the exposure means (exposure device) 1. This electrostatic latent image is developed by the developing means 13 with toner (developer). As a result, a toner image corresponding to the image information is formed on the surface of the photosensitive drum 10.

  In synchronization with the formation of the toner image, the recording medium P is separated and fed one by one from the feeding cassette 6a by the pickup roller 6b. The recording medium P is conveyed to the registration roller pair 6d along the conveyance guide 6c. The registration roller pair 6 d sends out the recording medium P between the photosensitive drum 10 and the transfer unit 3. The transfer unit 3 transfers the toner image on the photosensitive drum 10 to the recording medium P. The recording medium P that has received the transfer of the toner image is conveyed along a conveyance guide 6e to a fixing device 5 as a fixing unit.

  In the fixing device 5, when the pressure roller 5c and the heater 5a are built in, the recording medium P is nipped and conveyed at a nip portion (fixing nip portion) between the fixing roller 5b, and heat and pressure are applied to the recording medium P in the conveyance process. In addition, the unfixed toner image is fixed on the surface of the recording medium. The recording medium P exiting the fixing device 5 is discharged onto a discharge tray 7 provided on the upper portion of the apparatus main body D by a discharge roller 6f.

  After the toner image is transferred, the photosensitive drum 10 is subjected to the next image formation after the cleaning unit 14 removes the remaining deposits such as the residual toner on the outer peripheral surface.

  The photosensitive drum 10, the charging unit 8, the developing unit 13, and the cleaning unit 14 are integrally formed as a process cartridge C. The cartridge C is detachably mounted on the apparatus main body D constituting the housing of the image forming apparatus.

  Reference numeral 6 denotes a conveying means for conveying the recording medium P. The conveying means 6 includes a pickup roller 6b, conveyance guides 6c and 6e, a registration roller pair 6d, a discharge roller 6f, and the like.

(2) Configuration of Cartridge C In the following description, regarding the cartridge C or a member constituting the cartridge C, the short direction is a direction in which the cartridge is attached to and detached from the apparatus main body D unless otherwise specified. Similarly, the longitudinal direction is a direction orthogonal to (crossing) the direction in which the cartridge B is attached to and detached from the apparatus main body D, and is also the axial direction of the photosensitive drum 10. With respect to the cartridge C, the front is the surface of the photosensitive drum external exposure opening 2 (FIG. 3) viewed from the direction in which the cartridge C is attached to and detached from the apparatus main body D. The back surface is the surface on the opposite side when the cartridge C is viewed from the front. Left and right are left or right surfaces when the cartridge C is viewed from the front. The upper surface is a surface positioned upward in a state where the cartridge C is mounted on the apparatus main body D. The lower surface is a surface positioned below in a state where the cartridge C is mounted on the apparatus main body D.

  FIG. 3 is a structural model diagram of an example of the cartridge C. FIG. 5 is a perspective view showing the relationship between the developing device frame 51 of the photoconductor unit B and the developing unit A and the side cover. FIG. 6 is an exploded perspective view of the photoreceptor unit B. FIG.

In FIG. 3, a developing unit (developing device) A assembled integrally with the photosensitive unit B includes a toner storage frame 61 as a first frame, a developing means 13, and a second frame. A developing device frame 51. The storage frame 61 stores toner (not shown). Reference numeral 61 a denotes a first opening ( FIG. 15 ) provided in the storage frame 61 for supplying toner in the storage frame 61. The developing unit 13 includes toner feeding members 23 and 24, a developing roller 20 as a developer carrying member, a developing blade 29, and an ejection prevention sheet 25. Of the developing means 13, the feed members 23 and 24 are rotatably supported by the storage frame 61. The developing roller 20, the developing blade 29, and the ejection prevention sheet 25 are each supported by the developing frame 51. The developing roller 20 rotatably supported by the developing device frame 51 carries toner on its outer peripheral surface (surface) and supplies toner to the latent image formed on the surface of the photosensitive drum 10 to form a visible image. It is. The developing blade 29 imparts triboelectric charge to the toner on the surface of the developing roller 20 and forms a toner layer. The ejection prevention sheet 25 seals the lower opening between the developing roller 20 and the developing frame 51 to prevent toner leakage on the lower side of the developing roller 20. 51 a is a second opening ( FIG. 5 ) provided in the developing device frame 51. The second opening 51 a is for receiving toner supplied from the storage frame 61 through the first opening 61 a and guiding the toner to the developing roller 20. The opening 51 a faces the opening 61 a of the storage frame 61.

  In the developing means 13, the feed members 23 and 24 rotate in the direction of the arrow. As a result, the toner in the storage frame 61 is supplied into the developing frame 61 through the openings 61a and 51a. Then, toner is carried on the surface of the developing roller 20 that includes the fixed magnet 28 and rotates. A blade 29e that is integrally formed with or adhered to the developing blade 29 imparts triboelectric charge to the toner. At the same time, a toner layer with a regulated layer thickness is formed on the surface of the developing roller 20. The developing roller 20 has spacer rollers 26a and 26b (FIG. 8) at both longitudinal ends. The developing roller 20 is urged to the photosensitive drum 10 via the rollers 26a and 26b. As a result, a certain clearance is maintained between the surface of the developing roller 20 and the surface of the photosensitive drum 10. Then, toner is supplied from the surface of the developing roller 20 to the developing area on the surface of the photosensitive drum 10, and a toner image corresponding to the latent image is formed.

The photoreceptor unit B includes a cleaning frame 12. The cleaning frame 12 supports a photosensitive drum 10, a charging roller 11 as a charging unit, and a cleaning blade 14 as a cleaning unit. The photosensitive drum 10 is rotatably supported on the cleaning frame 12 by a shaft 15 and a bearing 16 (FIG. 5). The charging roller 11 is rotatably supported by the cleaning frame 12 via bearings 17 and 18 ( FIG. 6 ). The cleaning blade 14 has a blade 14a that comes into contact with the surface of the photosensitive drum 10, and scrapes residual toner from the surface of the photosensitive drum 10 into the waste toner chamber 12a by the blade 14a.

  The photosensitive drum external exposure opening 2 provided between the cleaning frame 12 and the developing frame 51 on the upper surface of the cartridge C exposes the surface of the photosensitive drum 10 to the outside. A laser beam L is irradiated on the surface of the photosensitive drum 10 through the opening 2 to form a latent image.

(3) Configuration of Cartridge C Guide and Cartridge Guide of Apparatus Main Body D As shown in FIG. 4, when the cartridge C is mounted on the apparatus main body D, the opening / closing door 101 of the apparatus main body D is arranged around the shaft 101a. The cartridge insertion opening S provided in the apparatus main body D is opened by rotating the main body D upward. Then, in the cartridge C, the circular convex portion 15a of the shaft 15 at both longitudinal ends of the cleaning frame 12 and the cylindrical circular convex portion 16a of the bearing 16 are respectively provided with concave positioning guides 102a provided on the side plate pair of the apparatus main body D. , 102b (mounting part) . Further, the guide convex portions 12a and 12b provided above the circular convex portions 15a and 16a in the cleaning frame 12 are respectively formed into concave introduction guides 103a and 103b (mounting portions) provided on the side plate pairs of the apparatus main body D. Support. Then, the cartridge B is inserted into the insertion slot S from the cleaning frame body 12 side in the short direction. As the cartridge B is inserted, the circular convex portion 15a and the circular convex portion 16a abut against the abutting surfaces 102a1 and 102b1 of the positioning guides 102a and 102b, respectively, and are positioned. As a result, the cartridge C is set at the image forming position. Then, the opening / closing door 101 is rotated about the shaft 101a toward the apparatus main body D to close the cartridge insertion opening S.

  In the mounted state in which the cartridge C is set to the apparatus main body A1 at the image forming position, a coupling member (not shown) provided at the longitudinal end portion on the bearing 16 side of the photosensitive drum 10 is provided in the apparatus main body D (not shown). The main body coupling member is coupled. The main body coupling member is rotated by a motor (not shown) provided in the apparatus main body D. The photosensitive drum 10 is rotated by the rotation of the motor, and the developing roller 20 and the feeding members 23 and 24 are rotated through a gear train (not shown).

  A main body electrical contact (not shown) provided on the apparatus main body D is electrically connected to an electrical contact (not shown) provided on the cartridge C. As a result, a charging bias can be applied to the charging roller 11 of the cartridge C from a power supply unit (not shown) of the apparatus main body D, and a developing bias can be applied to the developing roller 20.

  The removal of the cartridge C from the inside of the apparatus main body D is performed in the reverse procedure to the above mounting procedure.

(4) Housing Configuration of Cartridge C FIG. 7 is an explanatory view showing the housing configuration of the cartridge C, and is an exploded perspective view showing a state before the cartridge C is assembled.

  The cartridge C of this embodiment is a cartridge obtained by integrally connecting the developing unit A and the photosensitive unit B. The storage frame 61 and the cleaning frame 12 are positioned by first and second side covers 44 and 45 provided on the outer sides of both longitudinal ends thereof. The storage frame 61 and the cleaning frame 12 are integrally coupled and fixed to the side covers 44 and 45 by coupling means such as screws, resin bonding, welding, and adhesion. The developing frame 51 is slidable between the storage frame 61 and the cleaning frame 12 in the direction ar1 approaching the photosensitive drum 10 and the direction ar2 moving away from the photosensitive drum 10 by the side covers 44 and 45. It is supported.

(5) Configuration of the Development Frame 51 in the Development Unit A FIG. 8 is an explanatory diagram showing a support structure for the development roller 20 and the development blade 29 in the development frame 51. FIG. 9 is an explanatory view showing a support form of the developing device frame 51 by the side cover 44. FIG. 10 is an explanatory view showing a support form of the developing device frame 51 by the side cover 45.

  In the developing frame 51, a first end cover 42 is coupled and fixed to one longitudinal end, and a second end cover 43 is coupled and fixed to the other longitudinal end. The end covers 42 and 43 hold the developing roller 20 and the developing blade 29 by being coupled and fixed to the developing frame 51. The developing roller 20 is rotatably supported by end covers 42 and 43 through bearings 27a and 27b, respectively. The rollers 26 a and 26 b provided at both longitudinal ends of the developing roller 20 have an inner diameter slightly larger than the outer diameter of the developing roller 20 and have a necessary gap thickness between the photosensitive drum 10 and the developing roller 20. Is formed. The developing blade 29 is positioned by being fitted to positioning bosses 51b and 51c provided on the developing frame 51, and is fixed to the developing frame 51 by screws 95a and 95b. As a result, the blade 29e is brought into contact with the surface of the developing roller 20.

  At one end of the developing roller 20 on the end cover 42 side, a developing roller gear 36 that transmits a rotational driving force to the developing roller 20, a retaining roller of the developing roller gear 36, and a fixed magnet 28 built in the developing roller 20 are supported. The fixing members 35 are attached.

  At both longitudinal end portions of the developing blade 29, toner regulating members 33 and 34 for scraping the toner at the end portion of the developing roller 20 toward the inside in the longitudinal direction are attached.

  As shown in FIG. 8, the end cover 42 has slide planes 42 a and 42 b that are slidably supported by the side cover 44. The slide planes 42a and 42b are inclined in parallel to the photosensitive drum 10 side. The end cover 43 has slide planes 43a and 43b that are slidably supported on the side cover 45 in the vertical direction. The slide planes 43a and 43b are also inclined in parallel to the photosensitive drum 10 side. As shown in FIG. 9, the side cover 44 has guide planes 44a and 44b at portions facing the slide planes 42a and 42b. The guide planes 44a and 44b are inclined in parallel to the photosensitive drum 10 side. As shown in FIG. 10, the side cover 45 has guide planes 44a and 44b at portions facing the slide planes 42a and 42b. The guide planes 44a and 44b are inclined in parallel to the photosensitive drum 10 side. Then, the slide planes 42a and 42b of the end cover 42 are brought into contact with the guide planes 44a and 44b of the side cover 44, and the slide planes 43a and 43b of the end cover 43 are brought into contact with and supported by the guide planes 44a and 44b of the side cover 45, respectively. (FIGS. 9 and 10). In the developing frame 51 having the end covers 42 and 43 at both longitudinal ends, the slide planes 42a and 42b of the end covers 42 and 43 are supported by the guide planes 44a and 44b of the side cover 44. Is slidable. In other words, the developing device frame 51 is connected to the storage frame 61 and the end covers 42 and 43 so as to be movable in the ar1 and ar2 directions.

  As shown in FIG. 4, the developing device frame 51 having end covers 42 and 43 at both longitudinal ends is an urging force as a pressure member provided between the end covers 42 and 43 and the side covers 44 and 45. It is urged toward the photosensitive unit B by the springs 32a and 32b. As a result, the developing roller 20 is pressed to a state where a certain clearance is formed on the photosensitive drum 10 by the rollers 26a and 26b.

(6) Seal structure between the developing frame 51 and the storage frame 61 FIG. 11 is a perspective view of the developing frame 51 viewed from the storage frame 61 side. FIG. 12 is a perspective view of an example in which a liquid elastomer 71 is applied to the developing device frame 51. FIG. 13 is a perspective view of the developing frame 51 to which the elastomer 71 is applied as viewed from the storage frame 61 side.

  Hereinafter, a method for assembling the developing frame 51 and the storage frame 61 will be described.

First, the developing frame 51 shown in FIG. 11 is prepared (developing frame preparing step (second preparing step) ). The developing device frame 51 has a flange 51d as a second coupling portion around the opening 51a. Here, the flange 51d may not have the same configuration over the entire periphery of the second opening 51a. That is, it may have a partially different configuration. In order to apply an adhesive liquid elastomer (elastic polymer substance) 71 to the flange 51d, a base 51e as a coating portion is formed in a rectangular frame shape so as to surround the opening 51a. In the base 51e, the tip surface 51e1 for applying the liquid elastomer 71 is provided with a recess 51e11 over the entire circumference of the tip surface 51e1. Further, a connecting portion 51e12 for connecting the application start end 71a of the liquid elastomer 71 and the application end portion 71b (FIG. 14) is provided at the center in the longitudinal direction on the upper end side of the flange 51d. The connecting portion 51e12 is formed wider than the distal end surface 51e1.

  As shown in FIG. 12, the dispenser 96 moved by the NC linear motion unit is moved around the base 51e from the connecting portion 51e12 along the base 51e in the direction of the arrow to make a round. In this way, the heated liquid elastomer 71 is applied to the base 51e tip surface 51e1 (application process). Then, the liquid elastomer 71 is cooled and solidified. As shown in FIG. 13, the elastomer 71 solidified on the tip 51e1 of the base 51e enters the recess 51e11 to increase the contact area with the application surface 51e1 (HH line enlarged sectional view of FIGS. 1 and 18). , GG line expanded sectional view). Therefore, the connection strength of the elastomer 71 with respect to the application surface 51e1 can be increased. Hereinafter, the front end surface 51e1 of the base 51e is referred to as a coating surface 51e1. Further, the solidified elastomer 71 is simply referred to as an elastomer 71.

  FIG. 14 is an explanatory diagram of the elastomer 71 in the connecting portion 51e12 of the base 51e.

  On the joint portion 51e12, the elastomer 71 has the application start end portion 71a and the application end portion 71b adjacent to each other in the width direction of the connection portion 51e12. In the elastomer 71, the cross-sectional shape in the width direction is a semicircular shape (a view taken along the arrow JJ). The surface shapes of the start end portion 71 and the end end portion 71b are circular arc shapes (a view taken along the arrow KK).

  FIG. 15 is a perspective view of the storage frame 61 viewed from the developing frame 51 side. FIG. 16 is a diagram illustrating a state before the elastic members 81, 82, 83, 84 are attached to the storage frame 61. FIG. 17 is a diagram illustrating a state after the elastic members 81, 82, 83, and 84 are attached to the storage frame 61.

Next, as shown in FIG. 15, a storage frame 61 is prepared (storage frame preparation step (first preparation step) ). The storage frame 61 has recesses 61g1, 61g2, 61g3, 61g4 in outer regions 61b5, 65b6, 65b7, 65b8 of four corners (corner portions) of the opening 61a in the flange 61b as the first coupling portion. The recesses 61g1, 61g2, 61g3, 61g4 are formed at positions facing the positions of the elastomer outside the four corners of the opening 51a in the elastomer 71 applied to the developing device frame 51. The recesses 61g1, 61g2, 61g3, 61g4 are surrounded by ribs 61h1, 61h2, 61h3, 61h4 protruding toward the developing device frame 51.

  Further, the storage frame 61 has ribs 61f1, 61f2, 61f3, 61f4 in an outer region of a straight portion other than the four corners of the opening 61a in the flange 61b. The ribs 61f1, 61f2, 61f3, 61f4 are formed on the elastomer 71 applied to the developing device frame 51 at positions outside the elastomer positions of the straight portions (straight portions) other than the four corners of the opening 51a. Yes, and protrudes to the developing frame 51 side. The protruding heights of the ribs 61f1, 61f2, 61f3, 61f4 in the straight portion are higher than the protruding heights of the ribs 61h1, 61h2, 61h3, 61h4 of the recesses 61g1, 61g2, 61g3, 61g4.

  One end side in the short direction of the elastic members 81, 82, 83, 84 is attached to the front end surfaces of the ribs 61f1, 61f2, 61f3, 61f4 of the straight portion by double-sided tape, heat welding, or the like (FIGS. 16 and 17). The elastic members 81, 82, 83, 84 are sheet-like and made of metal or resin.

  A liquid elastomer 74 is injected into the recesses 61g1, 61g2, 61g3, 61g4 using a dispenser 96 (FIG. 12) (FIGS. 16 and 17). At that time, the elastomer 74 is injected until it is slightly higher than the elastic members 81, 82, 83, and 84 and closely contacts the ends of the adjacent elastic members 81, 82, 83, and 84, and is cooled and solidified. Is done.

  The storage frame 61 has a rib 61i as an urging member on the flange 61b. The rib 61 i protrudes toward the developing frame 51 at a position facing the connecting portion 51 e 12 of the flange 51 d of the developing frame 51. Hereinafter, the rib 61i will be described in detail with reference to FIG. 1, FIG. 15, and FIG.

  18 shows a state in which the developing frame 51 and the storage frame 61 are combined with each other in a state where the storage frame 61 does not have the rib 61i and the elastic members 81, 82, 83, and 84 (that is, the elastomer 71 is not deformed). It is sectional drawing showing the state at the time of hitting.

  i) The protrusion height H3 of the rib 61i toward the developing frame 51 (enlarged sectional view of the E portion in FIG. 1) satisfies the following relationship.

H3 ≧ H1-H2
As shown in FIG. 18, H1 is a dimension from the storage frame 61 to the elastomer 71 when the developing frame 51 and the storage frame 61 are combined. That is, the distance from the surface 61n of the flange 61b where the rib 61i is provided in the storage frame 61 to the apexes 71g and 71h (FIG. 15) of the elastomer 71. H2 is the thickness of the elastic member 81 (FIG. 1).

  ii) The length L1 (FIG. 15) in the longitudinal direction of the developing frame 51 of the rib 61i satisfies the following relationship.

L1 = L2 + L3
L2 is a dimension from the application start point 71n of the liquid elastomer 71 to a predetermined position beyond the apex 71g of the start end 71a. L3 is a dimension from the start point 71n to a predetermined position beyond the vertex 71h of the end portion 71b.

  Therefore, L2 satisfies L4 and L3 satisfies L5, and the following relationships are satisfied.

L2 ≧ L4
L3 ≧ L5
L4 is a dimension from the starting point 71n to the vertex 71g of the starting end 71a. L5 is a dimension from the starting point 71n to the vertex 71h of the terminal end 71b.

  iii) The width direction length W1 (FIG. 15) of the rib 61i satisfies the following relationship.

W1 = W2 + W3
W2 is a dimension from the extension line 71p of the adjacent surface of the starting end portion 71a and the terminal end portion 71b to a predetermined position exceeding the center line 71j in the short direction of the starting end portion 71a. W3 is a dimension from the extension line 71p to a predetermined position exceeding the center line 71k in the short direction of the terminal end 71b.

  Therefore, W2 satisfies W4 and W3 satisfies W5, and the following relations are satisfied.

W2 ≧ W4
W3 ≧ W5
W4 is a dimension from the extended line 71p to the center line 71j in the short direction of the start end 71a. W5 is a dimension from the extension line 71p to the center line 71k in the short direction of the terminal end 71b.

  And as shown in FIG. 14, the recessed part 51e2 as a level | step difference arises between the start end part 71a and the terminal part 71b of the elastomer 71 (connection part of the elastomer 71). As shown in FIG. 15, the rib 61i is formed in a size having a surface area that covers the recess 51e2.

  FIG. 19 is a perspective view showing a state in which the developing frame 51 and the storage frame 61 are movably coupled (connected) by joining the flanges 51d and 61b. FIG. 1 is a sectional view showing the connected state. FIG. 20 is an explanatory view showing the state of the start end portion 71a and the end end portion 71b of the elastomer 71 of the developing device frame 51 in the connected state.

  As shown in the enlarged sectional view along the line H-H, the elastomer 71 applied to the developing frame 5 is an elastic member around the openings 51a and 61a in a state where the developing frame 51 and the storage frame 61 are movably connected. 81, 82, 83, 84. That is, the elastic members 81, 82, 83, 84 are coupled (contacted) to the third coupling portions 81 a, 82 a, 83 a, 84 a on the free end side (the other end side in the short side direction) (elastic member coupling step).

  Further, the third coupling portion 81a of the elastic member 81 is brought into close contact with the elastomer 71 of the developing device frame 51 by the rib 61i of the storage frame 61 (enlarged portion E of FIG. 1 corresponding to the arrow EE in FIG. 19). Sectional view). A third coupling portion 81a is coupled (adhered) to the starting end portion 71a and the terminating end portion 71b of the elastomer 71 by a rib 61i. Here, before the rib 61i and the third coupling portion 81a come into contact with each other, a gap 51e3 is formed between the portions 71c and 71d constituting the recess 51e2 and the third coupling portion 81a or is in a state where it is likely to occur. Yes. However, when the rib 61i and the third coupling portion 81a come into contact with each other, the third coupling portion 81a biases the third coupling portion 81a in the direction in which the concave portion 51e2 is located. As a result, the third coupling portion 81a is coupled (contacted) with the portions 71c and 71d so as to fill the gap 51e3 (FIG. 20). In addition, the elastomers 71 and 74 provided in the developing frame 51 and the storage frame 61 are joined (contacted) to each other (G-G enlarged sectional view). Thus, the flanges 51d and 61b are sealed with the elastomers 71 and 74 (hereinafter referred to as seals). Thereby, it is possible to restrict (prevent) the toner stored in the storage frame 61 from leaking between the flanges 51d and 61b.

  The elastomer 71 has high adhesiveness and can be sealed with a low compression amount. That is, when the gap between the flanges 51d and 61b is sealed with the elastomer 71, the amount of compression of the elastomer 71 can be reduced. Therefore, the repulsive force by the elastomer 71 can be kept low. Accordingly, it is possible to reduce the pressure (hereinafter referred to as D pressurization) that presses against the surface of the photosensitive drum 10 via the rollers 26a and 26b provided at both longitudinal ends of the developing roller 20. In summary, the D pressure can be kept low by interposing the elastomer 71 between the flanges 51d and 61b and sealing the flanges 51d and 61b.

  The amount of wear of the shaft 15 that rotatably supports the photosensitive drum 10 and the photosensitive drum 10 and the bearing 16 that rotatably supports the photosensitive drum 10 and the photosensitive drum 10 by suppressing the D pressure to be low. The amount of wear can be reduced. In addition, the wear amount of the developing roller 20 and the bearings 27a and 27b that rotatably support the developing roller 20 can be reduced. Further, the amount of wear on the rollers 26a and 26b and the surface of the photosensitive drum 10 pressed against the surface of the photosensitive drum 10 can be reduced. For this reason, durability life can be increased about each said member 10,15,16,20,26a, 26b, 27a, 27b.

  Further, when the photosensitive drum 10 rotates, sliding heat generated at the sliding portion between the photosensitive drum 10 and the shaft 15 and the sliding portion between the photosensitive drum 10 and the bearing 16 can be reduced. Further, sliding heat generated at the sliding portion between the developing roller 20 and the bearings 27a and 27b during the rotation of the developing roller 20 can be reduced. Further, sliding heat generated at the sliding portion between the surface of the photosensitive drum 10 and the rollers 26a and 26b when the photosensitive drum 10 and the developing roller 20 are rotated can be reduced. For this reason, the number of cooling fans provided in the apparatus main body D can be reduced, and power consumption can be reduced accordingly.

  Further, the bending of the developing roller 20 pressed against the photosensitive drum 10 can be reduced. Thereby, the occurrence of density unevenness in the image is reduced, and the image quality can be improved.

  Further, when the compression amount of the elastomers 71 and 74 is increased due to the dimensional variation of the development frame 51 or the storage frame 61 or the development frame 51 and the storage frame 61 (the development frame or / and the storage frame). Even so, the D pressure can be kept small. That is, by using the elastic sheet-like elastic members 81, 82, 83, 84, the influence of the variation in the dimensions on the developing frame 51 and / or the storage frame 61 on the repulsive force of the elastomers 71, 74 is reduced. Therefore, the D pressurization can be kept small.

  Further, the elastomer 71 is provided on the base 51e of the developing frame 51, the elastomer 74 is provided at the corner of the flange 61d of the storage frame 61, and the elastic members 81, 82, 83, and 84 are provided at the straight portion of the flange 61b. However, conversely, a base is formed on the storage frame 61 and an elastomer 71 is provided thereon, an elastomer 74 is provided at a corner of the flange 51d of the developing device frame 51, and elastic members 81 and 82 are provided on the flange 51d linear portion. , 83, 84 may be provided.

  Further, the elastic members 81, 82, 83, 84 may be third coupling portions that are integrally formed with the storage frame body 61 or the developing frame body 51.

  In this embodiment, the third coupling portion 81a of the elastic member 81 is brought into close contact with the elastomer 71 of the developing frame 51 by the rib 61i of the storage frame 61. However, instead of the rib 61i, a foam or an elastomer may be used. Good. FIG. 21 is a cross-sectional view of the joint portion of the housing frame 61 having the foam 91 instead of the rib 61 i and the flanges 61 b and 51 d of the developing frame 51 having the elastomer 71. FIG. 22 is a cross-sectional view of the joint portion of the housing frame 61 having the elastomer 72 instead of the rib 61 i and the flanges 61 b and 51 d of the developing device frame 51 having the elastomer 71. By using the elastic foam 91 and elastomer 72 instead of the rigid rib 61i, the influence of the variation in the dimensions on the developing frame 51 and / or the storage frame 61 on the repulsive force of the elastomers 71 and 74 is reduced. be able to. Therefore, D pressurization can be suppressed small. Even if the foam 91 and the elastomer 72 are provided not on the flange 61b of the housing frame 61 but on the surface on the flange 61b side of the third coupling portion 81a, the same effect can be obtained.

(7) Modification of Assembling Method In this embodiment, a method of applying the liquid elastomer 71 to one of the frames 51 and 61 is adopted, but a method of applying the liquid elastomer 71 to the elastic member 81 (elasticity You may employ | adopt a member application | coating process. It should be noted that the workability during assembly is better when applied to the frame bodies 51 and 61 than when applied to the elastic member 81. In addition, as the elastic member application step, the elastic member 81 is provided on (attached to) the elastic member 81 provided (attached) to the step of applying the elastomer 71 to the single item (single item application step) and the frame 51, 61. Any of the steps of applying the elastomer (post-bonding application step) is used. At this time, the former improves the workability during assembly. In addition, the process (frame body coupling | bonding process) of couple | bonding the elastomer 71 couple | bonded with the elastic member 81 is used for either one of the frame bodies 51 and 61 after the single item application | coating process mentioned above. Or the process of attaching the elastic member 81 couple | bonded with the elastomer 71 to either one of the frames 51 and 61 is used. Moreover, after the application | coating process after a coupling | bonding, either one of the frame bodies 51 and 61 and the elastomer 71 are couple | bonded.

  Also, the elastomer 71 and the elastic member 81 applied to one of the frame bodies 51 and 61 are coupled (elastic member coupling step), and then the elastic member 81 is coupled to either one of the frame bodies 51 and 61 ( (Elastic member attachment process) You may attach.

It should be noted that the process in the present embodiment described above has better workability than these modified examples.
(8) Others In this embodiment, the liquid elastomers 71, 72, and 74 are cooled and solidified. However, the solidification of the liquid elastomers 71, 72, and 74 is not limited to cooling. For example, as the liquid elastomers 71, 72, and 74, those that are solidified by a chemical change when two liquids are mixed may be used. Also in Example 2 described below, the same liquid elastomer can be used.

  Further, when assembling the developing unit A of the present embodiment, the developing frame 51 and the storage frame 61 can be coupled only by moving the storage frame 61 in one direction relative to the development frame 51. it can. Therefore, the assemblability can be improved.

  Another example of the developing unit A will be described.

  In the present embodiment, the same members and portions as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. Similarly to the first embodiment, the developing unit A of the present embodiment is integrally coupled with the photosensitive unit B to constitute the cartridge C.

  FIG. 23 is an explanatory diagram of the storage frame 61 in the developing unit A of this embodiment. FIG. 24 is an explanatory diagram showing the relationship between the rib 61 i of the storage frame 61, the elastic member 85, and the elastomer 71 of the development frame 51 in the developing unit A.

  The storage frame 61 is obtained by attaching a rectangular frame-shaped elastic member 85 to a rectangular frame-shaped rib 61m provided around the flange 61b with a double-sided tape 91, and the other configuration is the storage of the first embodiment. It is the same as the frame body 61. The elastic member 85 is a sheet member that is stretchable, elastic, or flexible (for example, a foam sheet, a rubber sheet, or the like). That is, instead of the ribs 61h1, 61h2, 61h3, 61h4 and the elastomer 74 provided in the flange 61b in the first embodiment, the flange 61b is provided with a rectangular frame-shaped rib 61m, and the double-sided tape 91 is provided on the rib 61m with the elastic member 85. Is pasted.

  Therefore, in the developing unit A of the present embodiment, the same operations and effects as those of the developing unit A of the first embodiment can be obtained.

FIG. 5 is a cross-sectional view illustrating a state in which the developing frame and the storage frame are joined to each other by connecting the developing frame and the flange of the storage frame in the developing unit according to the first exemplary embodiment. 1 is a configuration model diagram of an example of an electrophotographic image forming apparatus. FIG. 3 is a structural model diagram of an example of a process cartridge. FIG. 5 is an explanatory diagram illustrating a configuration of a process cartridge guide and a cartridge guide of the apparatus main body. FIG. 4 is a perspective view illustrating a relationship between a developing device frame and a side cover of a photoconductor unit and a developing unit. It is a disassembled perspective view of a photoreceptor unit. It is explanatory drawing showing the housing structure of a process cartridge. It is explanatory drawing showing the support structure of the developing roller and developing blade in a developing frame. It is explanatory drawing showing the support form of the image development frame with a side cover. It is explanatory drawing showing the support form of the image development frame with a side cover. FIG. 5 is a perspective view of the developing frame as viewed from the storage frame. It is a perspective view of an example which applies a liquid elastomer to a development frame. It is the perspective view which looked at the image development frame with which the elastomer was applied from the storage frame side. It is explanatory drawing of the solidified elastomer in the base connection part of a storage frame. FIG. 5 is a perspective view of a storage frame viewed from the developing frame side. It is a figure showing the state before attaching an elastic member to a storage frame. It is a figure showing the state after attaching an elastic member to a storage frame. It is sectional drawing showing the state at the time of uniting a developing device frame and a storage frame in the state without a rib and an elastic member in a storage frame. It is a perspective view showing the state which joined the development frame and the flange of a storage frame, and connected the development frame and the storage frame so that movement was possible. It is explanatory drawing showing the mode of the start end part and terminal part of the solidified elastomer of the development frame in the connection state of a development frame and a storage frame. It is sectional drawing of the flange junction part of the image development frame which has a storage frame body which replaces with a rib with a foam, and the solidified elastomer. It is sectional drawing of the flange joint part of the storage frame which has the elastomer solidified instead of the rib, and the image development frame which has the solidified elastomer. FIG. 10 is a diagram illustrating a developing unit according to a second embodiment, and is an explanatory diagram of a storage frame body in the developing unit. FIG. 6 is an explanatory diagram illustrating a relationship between a rib of a storage frame body, an elastic member, and a solidified elastomer of the development frame body 51 in the developing unit.

Explanation of symbols

A ... Development unit, B ... Photoconductor unit, C ... Process cartridge D ... Main unit, ar1, ar2 ... Slide direction, P ... Recording medium,
10 .... photosensitive drum, 20 .... developing roller,
51... Development frame, 51 a... Opening, 51 d.
61... Toner storage frame, 61 a... Opening, 61 b.
71, 72, 74 ... Elastomer, 61i ... Rib,
81, 82, 83, 85, 85... Elastic member

Claims (11)

A developing device used in an electrophotographic image forming apparatus for forming an image on a recording medium,
A developer carrier for developing a latent image formed on the electrophotographic photosensitive member using a developer;
A first frame for storing the developer, the first frame having a first opening for supplying the developer and a first coupling portion provided around the first opening. Body,
A second frame having the developer carrier, a second opening for receiving the supply of the developer from the first opening, and a second coupling portion provided around the second opening; ,
A sheet-like elastic member provided in one of the first coupling portion and the second coupling portion, and the first frame and the first frame in a state where the first opening and the second opening are opposed to each other. The first coupling portion and the second coupling portion so that the developer can be moved and the developer leaks between the first coupling portion and the second coupling portion. An elastomer that binds either the other of the two coupling portions and the elastic member;
An urging member provided on the one side, wherein the urging member urges the elastic member toward a step generated in the elastomer;
A developing device comprising: The developing device according to claim 1, wherein one end side of the elastic member is attached to the one side, and the other end side of the elastic member is coupled to the elastomer.   The developing device according to claim 2, wherein the other end side is configured not to contact either the first frame body or the second frame body.   The developing device according to claim 1, wherein the elastomer is applied to the other side.   The developing device according to claim 1, wherein the urging member has elasticity. A process cartridge that is detachably attached to an apparatus main body of an electrophotographic image forming apparatus that forms an image on a recording medium,
An electrophotographic photoreceptor;
A developer carrying member for developing a latent image formed on the electrophotographic photosensitive member using a developer;
A first frame for storing the developer, the first frame having a first opening for supplying the developer and a first coupling portion provided around the first opening. Body,
A second frame having the developer carrier, a second opening for receiving the supply of the developer from the first opening, and a second coupling portion provided around the second opening; ,
A sheet-like elastic member provided in one of the first coupling portion and the second coupling portion, and the first frame and the first frame in a state where the first opening and the second opening are opposed to each other. The first coupling portion and the second coupling portion so that the developer can be moved and the developer leaks between the first coupling portion and the second coupling portion. An elastomer that binds either the other of the two coupling portions and the elastic member;
An urging member provided on the one side, wherein the urging member urges the elastic member toward a step generated in the elastomer;
A process cartridge comprising:   The process cartridge according to claim 6, wherein one end side of the elastic member is attached to the one side, and the other end side of the elastic member is coupled to the elastomer.   The process cartridge according to claim 7, wherein the other end side is configured not to contact any of the first frame and the second frame.   The process cartridge according to claim 6, wherein the elastomer is applied to the other side.   The process cartridge according to claim 6, wherein the urging member has elasticity. An electrophotographic image forming apparatus for forming an image on a recording medium,
An electrophotographic photosensitive member, a developer carrying member that develops a latent image formed on the electrophotographic photosensitive member using a developer, and a first frame that houses the developer, the developer being A first frame having a first opening for supply; a first coupling portion provided around the first opening; the developer carrier; and the developer from the first opening. A second frame having a second opening for receiving the supply of the second opening, and a second coupling portion provided around the second opening, and any one of the first coupling portion and the second coupling portion The first frame and the second frame can be moved in a state where the elastic member provided on one side and the first opening and the second opening are opposed to each other; and In order to restrict leakage of the developer from between the first coupling portion and the second coupling portion, the first coupling portion and the second coupling portion And an elastomer that is coupled to the elastic member, and a biasing member that is provided on the one and biases the elastic member toward a step generated in the elastomer. A cartridge,
A mounting portion for detachably mounting the process cartridge;
Conveying means for conveying the recording medium;
An electrophotographic image forming apparatus.