JP5906105B2 - Developing device and process cartridge - Google Patents

Description

  The present invention relates to an electrophotographic image forming apparatus (hereinafter referred to as an image forming apparatus), a developing device that can be attached to and detached from an apparatus main body, and a process cartridge.

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

  The process cartridge is an electrophotographic photosensitive drum (hereinafter referred to as a photosensitive drum) and process means acting on the photosensitive drum which are integrally formed into a cartridge that can be attached to and detached from the image forming apparatus. .

  The developing device is a cartridge in which the developer accommodating portion and the developing roller are integrally formed so as to be detachable from the image forming apparatus.

  The image forming apparatus main body is an image forming apparatus portion excluding the process cartridge and the developing device.

  Conventionally, in an image forming apparatus using an electrophotographic image forming process, a photosensitive drum and process means acting on the photosensitive drum are integrally formed into a cartridge. A process cartridge system is employed in which the cartridge is detachable from the main body of the image forming apparatus.

  According to this process cartridge system, maintenance of the image forming apparatus can be performed by the user himself / herself without depending on the service person, so that the operability can be remarkably improved.

  Therefore, this process cartridge system is widely used in image forming apparatuses.

  The process cartridge is divided into a developing unit and a photosensitive drum unit. In the developing unit, a developer regulating member that regulates the developing layer on the developing roller is fixed to the developing frame that is the first frame by screws. Further, a bearing, which is a second frame that supports the developing roller, is fixed with screws at two ends of the first frame in the developing roller axial direction (hereinafter referred to as the longitudinal direction). As described above, the developing roller and the developer regulating member are positioned and integrated with each other.

  As a method of fixing the second frame to the first frame, it is also known to use resin bonding instead of using screws in order to improve the space efficiency of the fixing portion. In this method, molten resin is poured between the first frame and the second frame, and the molten resin is cooled and solidified to fix the first frame and the second frame (see Patent Document 1). Furthermore, a method is also known in which a protrusion is provided on the first frame, a molten resin is fixed to the protrusion, and the first frame and the second frame are more firmly fixed (see Patent Document 2).

  In the photosensitive drum unit, a cleaning member that removes the developer on the photosensitive drum is fixed to a cleaning frame that is a first frame. Further, bearings, which are the second frame for supporting the photosensitive drum, are provided at two positions on both ends in the axial direction of the photosensitive drum of the first frame (same as the developing roller axial direction, hereinafter referred to as the longitudinal direction). Secured with screws. Thus, the photosensitive drum and the cleaning member are positioned and integrated.

  Also in the photosensitive drum unit, a method of fixing the second frame to the first frame using resin bonding is known as in the developing unit.

JP 2003-236877 A JP 2006-44025 A

  However, the above method avoids interference between a fixing space for fixing the developing blade to the first frame with screws and a fixing space for fixing the second frame for supporting the developing roller to the first frame. It is necessary to provide two fixed spaces separately. Similarly, the interference between the fixing space for fixing the cleaning blade to the first frame with screws and the fixing space for fixing the second frame for supporting the photosensitive drum to the first frame is avoided. It is necessary to provide a fixed space separately. As the image forming apparatus and the process cartridge to be used have been miniaturized, providing the two fixed spaces separately may restrict the design for miniaturizing the process cartridge.

  The present invention has been made in view of the above-described conventional points, and an object of the present invention is to provide a developing device and a process cartridge that can be downsized.

  In order to achieve the above object, a representative invention according to the present application is a developing device used in an image forming apparatus, which is a developer carrying member carrying a developer, and carried on the developer carrying member. A developer regulating member that regulates the amount of developer; a first frame that supports the developer regulating member; a fixing member that fixes the developer regulating member to the first frame; and the developer carrier. A resin molded part formed by injecting molten resin into a space formed by the first frame and the second frame, and projecting into the space A resin molded portion that engages with the first restricting portion of the fixing member and the second restricting portion provided on the second frame, and joins the first frame and the second frame. Features.

  In order to achieve the above object, another invention according to the present application is a process cartridge that is attachable to and detachable from an apparatus main body of an image forming apparatus, the photosensitive drum, and a cleaning that removes the developer from the photosensitive drum. A member, a first frame that supports the cleaning member, a fixing member that fixes the cleaning member to the first frame, a second frame that supports the photosensitive drum, and the first frame. A resin molded portion formed by injecting molten resin into a space formed by the second frame, provided in the first restricting portion and the second frame of the fixing member protruding into the space It has the resin molding part which engages with the made 2nd control part and couple | bonds said 1st frame and said 2nd frame.

  As described above, according to the present invention, the space for fixing the developing blade to the first frame and the space for fixing the second frame supporting the developing roller to the first frame can be saved. Can do. Further, the space for fixing the cleaning blade to the first frame and the fixing space for fixing the second frame supporting the photosensitive drum to the first frame can be saved.

Explanatory drawing of fixing method of developing frame and non-driving side bearing Schematic cross section of image forming apparatus Main cross section of process cartridge Perspective view of process cartridge as seen from non-drive side A perspective view of the developing device as seen from the non-driving side Positioning explanatory diagram of developing frame and non-driving side bearing Enlarged view of the development frame viewed from the front of the development blade Explanatory drawing of fixing method of developing frame and non-driving side bearing

(Example 1)
[Description of Image Forming Apparatus]
A first embodiment of the present invention will be described below with reference to the drawings.
In the following embodiments, a full-color image forming apparatus in which four process cartridges can be attached and detached is illustrated as an image forming apparatus.

  The number of process cartridges mounted on the image forming apparatus is not limited to this. It is appropriately set as necessary.

  For example, in the case of an image forming apparatus that forms a monochrome image, the number of process cartridges attached to the image forming apparatus is one. In the embodiments described below, a printer is exemplified as one aspect of the image forming apparatus.

[Schematic configuration of image forming apparatus]
FIG. 2 is a schematic cross-sectional view of the image forming apparatus of this embodiment.
As shown in FIG. 2, the image forming apparatus 1 is a four-color full-color laser printer using an electrophotographic image forming process, and forms a color image on a recording medium S. The image forming apparatus 1 is a process cartridge type, and a process cartridge is detachably attached to the image forming apparatus main body 2 to form a color image on the recording medium S.

  Here, regarding the image forming apparatus 1, the side on which the front door 3 is provided is the front surface (front surface), and the surface opposite to the front surface is the back surface (rear surface). Further, when the image forming apparatus 1 is viewed from the front, the right side is referred to as a driving side, and the left side is referred to as a non-driving side. FIG. 2 is a cross-sectional view of the image forming apparatus 1 as viewed from the non-driving side. Become the side.

  In the image forming apparatus main body 2, four process cartridges P (PY, PM, PC, and PK) of the first process cartridge PY, the second cartridge PM, the third process cartridge PC, and the fourth process cartridge PK are horizontal. Arranged in the direction.

  Each of the first to fourth process cartridges P (PY, PM, PC, PK) has the same electrophotographic image forming process mechanism, and the color of the developer is different. The first to fourth process cartridges P (PY / PM / PC / PK) receive a rotational driving force from a drive output unit (not shown) of the image forming apparatus main body 2.

  A bias voltage (charging bias, developing bias, etc.) is supplied from the image forming apparatus body 2 to each of the first to fourth process cartridges P (PY, PM, PC, PK) (not shown).

FIG. 3 is a sectional view of the process cartridge P of this embodiment.
As shown in FIG. 3, each of the first to fourth process cartridges P (PY, PM, PC, PK) of the present embodiment is charged as a photosensitive drum and process means acting on the photosensitive drum 4. And a cleaning unit 8 having cleaning means.

  Each of the first to fourth process cartridges P (PY, PM, PC, PK) includes a developing device 9 including a developing unit that develops the electrostatic latent image on the photosensitive drum 4.

  The cleaning unit 8 and the developing device 9 are coupled to each other. Further, a charging roller 5 is used as a charging unit, a cleaning blade 7 is used as a cleaning unit, and a developing roller 6 is used as a developing unit. A more specific configuration of the process cartridge will be described later.

  The first process cartridge PY contains a yellow (Y) developer in the developing frame 29 and forms a yellow developer image on the surface of the photosensitive drum 4.

  The second process cartridge PM contains a magenta (M) developer in the developing frame 29 and forms a magenta developer image on the surface of the photosensitive drum 4.

  The third process cartridge PC accommodates a cyan (C) developer in the developing frame 29 and forms a cyan developer image on the surface of the photosensitive drum 4.

  The fourth process cartridge PK contains a black (K) developer in the developing frame 29 and forms a black developer image on the surface of the photosensitive drum 4.

  Above the first to fourth process cartridges P (PY, PM, PC, PK), a laser scanner unit LB as an exposure unit is provided. The laser scanner unit LB outputs a laser beam Z corresponding to the image information. Then, the laser beam Z passes through the exposure window 10 of the process cartridge P and scans and exposes the surface of the photosensitive drum 4.

  Below the first to fourth process cartridges P (PY, PM, PC, PK), an intermediate transfer belt unit 11 as a transfer member is provided. The intermediate transfer belt unit 11 includes a driving roller 13, a turn roller 14, and a tension roller 15, and a transfer belt 12 having flexibility is stretched over the intermediate transfer belt unit 11.

  The lower surface of the photosensitive drum 4 of each of the first to fourth process cartridges P (PY, PM, PC, PK) is in contact with the upper surface of the transfer belt 12. The contact portion is a primary transfer portion. A primary transfer roller 16 is provided inside the transfer belt 12 so as to face the photosensitive drum 4.

  A secondary transfer roller 17 is brought into contact with the turn roller 14 via the transfer belt 12. A contact portion between the transfer belt 12 and the secondary transfer roller 17 is a secondary transfer portion.

  A feeding unit 18 is provided below the intermediate transfer belt unit 11. The feeding unit 18 includes a paper feeding tray 19 and a paper feeding roller 20 in which the recording media S are stacked and stored.

  A fixing unit 21 and a discharge unit 22 are provided at the upper left in the image forming apparatus main body 2 in FIG. The upper surface of the image forming apparatus main body 2 is a discharge tray 23.

  The recording medium S is fixed with a developer image by fixing means provided in the fixing unit 21 and is discharged to the discharge tray 23.

[Image forming operation]
The operation for forming a full-color image is as follows.
The photosensitive drum 4 of each of the first to fourth process cartridges P (PY / PM / PC / PK) is rotationally driven at a predetermined speed (in the direction of arrow D in FIG. 3, counterclockwise in FIG. 2).

  The transfer belt 12 is also rotationally driven at a speed corresponding to the speed of the photosensitive drum 4 in the forward direction (direction of arrow C in FIG. 2) with respect to the rotation of the photosensitive drum.

  The laser scanner unit LB is also driven. In synchronization with the driving of the laser scanner unit LB, the charging roller 5 uniformly charges the surface of the photosensitive drum 4 to a predetermined polarity and potential in each process cartridge. The laser scanner unit LB scans and exposes the surface of each photosensitive drum 4 with a laser beam Z according to the image signal of each color.

  As a result, an electrostatic latent image corresponding to the image signal of the corresponding color is formed on the surface of each photosensitive drum 4. The formed electrostatic latent image is developed by a developing roller 6 that is rotationally driven at a predetermined speed (in the direction of arrow E in FIG. 3, clockwise in FIG. 2).

  By the electrophotographic image forming process as described above, a yellow developer image corresponding to the yellow component of the full color image is formed on the photosensitive drum 4 of the first process cartridge PY. Then, the developer image is primarily transferred onto the transfer belt 12.

  Similarly, a magenta developer image corresponding to the magenta component of the full-color image is formed on the photosensitive drum 4 of the second process cartridge PM. The developer image is primary-transferred superimposed on the yellow developer image already transferred onto the transfer belt 12.

  Similarly, a cyan developer image corresponding to the cyan component of the full-color image is formed on the photosensitive drum 4 of the third process cartridge PC. Then, the developer image is primary-transferred superimposed on the yellow and magenta developer images already transferred onto the transfer belt 12.

  Similarly, a black developer image corresponding to the black component of the full color image is formed on the photosensitive drum 4 of the fourth process cartridge PK. Then, the developer image is primary-transferred superimposed on the yellow, magenta, and cyan developer images already transferred onto the transfer belt 12.

  In this way, a four-color full-color unfixed developer image of yellow, magenta, cyan, and black is formed on the transfer belt 12.

  On the other hand, the recording medium S is separated and fed one by one at a predetermined control timing. The recording medium S is introduced into a secondary transfer portion that is a contact portion between the secondary transfer roller 17 and the transfer belt 12 at a predetermined control timing.

  As a result, in the course of the recording medium S being transported to the secondary transfer section, the four color superimposed developer images on the transfer belt 12 are sequentially transferred onto the surface of the recording medium S in sequence.

[Overall configuration of process cartridge]
FIG. 3 is a sectional view of the process cartridge P of this embodiment.
FIG. 4 is a perspective view of the process cartridge P of this embodiment as viewed from the non-driving side.

  In the present embodiment, the first to fourth process cartridges P (PY, PM, PC, PK) have the same electrophotographic process mechanism, and the developer color and developer filling amount stored therein are the same. Each is different.

  The process cartridge P includes a photosensitive drum 4 and process means that acts on the photosensitive drum 4. Here, the process means removes the residual developer remaining on the surface of the photosensitive drum 4, the charging roller 5 for charging the photosensitive drum 4, the developing roller 6 for developing the latent image formed on the photosensitive drum 4. There is a cleaning blade 7 and the like. The process cartridge P is divided into a drum unit 8 and a developing device 9 (hereinafter referred to as a developing unit 9).

[Drum unit configuration]
As shown in FIGS. 3 and 4, the drum unit 8 includes a photosensitive drum 4, a charging unit 5, a cleaning blade 7, a cleaning frame body 26, a waste developer storage portion 27, a driving side cartridge cover member 24, and a non-driving side cartridge. The cover member 25 is used. The photosensitive drum 4 is rotatably supported by cartridge cover members 24 and 25 provided at both longitudinal ends of the process cartridge P. Here, the axial direction of the photosensitive drum 4 is defined as the longitudinal direction. The cartridge cover members 24 and 25 are fixed to the cleaning frame body 26 at both ends in the longitudinal direction of the cleaning frame body 26. As shown in FIG. 4, a coupling member 4 a for transmitting a driving force to the photosensitive drum 4 is provided on one end side in the longitudinal direction of the photosensitive drum 4. The coupling member 4 a engages with a coupling (not shown) as a drum drive output unit of the apparatus main body, and a driving force of a drive motor (not shown) of the apparatus main body is transmitted to the photosensitive drum 4. The charging roller 5 is supported by the cleaning frame 26 so as to be in contact with the photosensitive drum 4 and be driven to rotate. Further, the cleaning blade 7 is fixed to the cleaning frame 26 with screws so as to come into contact with the peripheral surface of the photosensitive drum 4 with a predetermined pressure. The residual transfer developer removed from the peripheral surface of the photosensitive drum 4 by the cleaning 7 is stored in a waste developer storage portion 27 in the cleaning frame 26. The cartridge cover members 24 and 25 are provided with support holes 24a and 25a for supporting the developing unit 9 so as to be swingable (movable). The support holes 24 a and 25 a are rotatably engaged with the cylindrical portion 32 a of the developing cover member 32 on the driving side of the developing unit 9 and the swing shaft 51 k of the non-driving side bearing 51.

[Development unit configuration]
FIG. 5 is a perspective view of the developing unit 9 of this embodiment as viewed from the non-driving side.
As shown in FIGS. 3 and 5, the developing unit 9 includes a developing roller 6, a developing blade 31, a developing frame 29, a bearing (the driving side bearing 50 and the non-driving side bearing 51 in FIG. 5), and the like. Yes. The developing frame 29 has a developer accommodating portion 49 that accommodates the developer supplied to the developing roller 6 which is a developer bearing member that bears the developer. Further, the developing frame 29 has fixing holes (non-driving side blade fixing holes 29a, driving holes) for fixing the developing blade 31 which is a developer regulating member for regulating the developer layer thickness on the circumferential surface of the developing roller 6. Side blade fixing holes 29b) are provided. The developing blade 31 is fixed to the developing frame 29 by fastening screws 52 and 53 as fixing members to the non-driving blade fixing hole 29a and the driving blade fixing hole 29b. The developing roller 6 is rotatably supported by a non-driving side bearing 51 and a driving side bearing 50. The non-driving side bearing 51 and the driving side bearing 50 that support the developing roller 6 are positioned and fixed to the developing frame 29, respectively. The positioning method and the fixing method will be described later.

  A developing roller gear 69 is installed at one end in the longitudinal direction of the developing roller 6 supported by the non-driving side bearing 51 and the driving side bearing 50. Further, a development input gear 70 is installed on the driving side bearing 50 so as to be connected to the development roller gear 69. The developing cover member 32 is fixed to the outside of the drive side bearing 50 so as to cover the developing roller gear 69 and the developing input gear 70. The developing cover member 32 is provided with a cylindrical portion 32a, and the developing input gear 70 is exposed from the opening 32b inside the cylindrical portion 32a. The development input gear 70 is engaged with a main body coupling member (not shown) when the process cartridge P is mounted on the apparatus main body 2, and a driving force from a drive motor (not shown) provided in the apparatus main body 2 is received. The driving force is transmitted to the developing roller gear 69.

[Positioning of development frame and bearing]
Next, a method for positioning and fixing the non-driving side bearing 51 and the developing frame 29 will be described. Hereinafter, the positioning method and the fixing method will be described using the first frame body as the developing frame body 29 and the second frame body as the non-driving side bearing 51 with reference to FIGS. 1, 6, 7, and 8. A similar configuration can be used for a positioning method and a fixing method of the developing frame 29 and the driving side bearing 50 on the driving side.

FIG. 6 is an enlarged view of the developing frame 9 on the non-driving side when the non-driving side bearing 51 is assembled.
As shown in FIG. 6, the developing frame 29 to which the base metal plate 31b of the developing blade 31 is fixed has a positioning hole 29c, a rotation stop hole 29d, and a developing frame side long abutting surface 29e. Furthermore, the developing device frame 29 has an injection recess 29f that is an injection part into which molten resin can be injected. At the entrance of the injection recess 29f, the developing device frame side long abutting surface 29e is arranged in a cylindrical shape, and there is a notch 29g in which a part of the developing device frame side long abutting surface 29e is cut out. The non-driving side bearing 51 has a positioning boss 51a, a rotation-stop boss 51b, and a bearing-side longitudinal abutment surface 51c. Further, the non-driving side bearing 51 has a support hole 51e for supporting the developing roller 6 and an injection path 51d for guiding the molten resin.

  When the non-driving side bearing 51 is assembled to the developing device frame 29, the positioning hole 29c and the positioning boss 51a are engaged, and the rotation stopping hole 29d and the rotation stopping boss 51b are engaged. Further, the non-driving side bearing 51 is positioned with respect to the developing frame 29 by closely contacting the developing frame side long abutting surface 29e and the bearing side long abutting surface 51c. At this time, the developing roller 6 is supported by the support hole 51 e of the non-driving side bearing 51 and positioned with respect to the developing blade 31. Further, the axial direction of the injection path 51 d of the non-driving side bearing 51 coincides with the axial direction of the injection recess 29 f of the developing frame 29.

[Method for fixing development frame and bearing (resin bonding method)]
Next, a resin bonding method for fixing the non-driving side bearing 51 to the developing frame 29 with a molten resin (resin molding portion 54) will be described.

  FIG. 7 shows an enlarged view of the developing frame 29 as viewed from the front direction of the developing blade 31 (the direction of arrow W in FIG. 6). FIG. 8 is a cross-sectional view of the injection path for the molten resin 54 of the developing frame 29 and the non-driving side bearing 51 in the A direction in FIG. FIG. 8A shows a cross-sectional view before assembling the developing blade 31 and the non-driving side bearing 51, and FIG. 8B shows a cross-sectional view after assembling the developing blade 31 and the non-driving side bearing 51. FIG. 1 shows a cross-sectional view in the A direction of FIG. 7 in a state where a resin molded portion 54 formed by injecting molten resin and solidifying is formed.

  As shown in FIG. 8A, the non-driving side bearing 51 has an injection path 51d that guides the molten resin in the arrow Q direction, which is the injection direction, in FIG. In the upstream flow path in the arrow Q direction of the injection path 51d, the dimension M in the direction orthogonal to the arrow Q direction is larger than the dimension N of the downstream flow path. That is, the non-driving side bearing 51 has the 2nd control part 51i used as a level | step difference in the injection path 51d. And the 2nd control part 51i is a surface which faced the upstream with respect to the injection | pouring direction (FIG. 8 arrow Q direction) in which molten resin is inject | poured.

  The developing frame 29 has an injection recess 29f for receiving the molten resin injected in the direction of arrow Q in FIG. Further, a notch 29g is provided in a part of the inner surface of the injection recess 29f. Further, the developing device frame 29 has a non-driving side blade fixing hole 29a in the direction of arrow J which intersects the direction in which the molten resin is injected (direction of arrow Q in FIG. 8A). The non-driving side blade fixing hole 29a is a through-hole penetrating the injection recess 29f. As shown in FIG. 8B, screws 52 as fixing members for fixing the base metal plate 31b of the developing blade 31 to the developing frame 29 are inserted into the non-driving side blade fixing holes 29a. When the screw 52 is inserted into the non-driving side blade fixing hole 29a and the base sheet metal 31b of the developing blade 31 is fixed to the developing frame 29, it protrudes into the injection recess 29f by a length L. This protruding portion is a part of the width U inside the injection recess 29f, and forms a width R portion that is narrower than the width U and is made of the bottom 52a of the screw 52 and the inner surface of the injection recess 29f. When the molten resin (not shown) is injected into the injection recess 29 after fixing the screw 52 to the developing frame 29 in this way, the portion protruding into the injection recess 29 of the screw 52 becomes the injected molten resin (not shown). It becomes the 1st control part 52b which controls (illustration).

  As described above, when the non-driving side bearing 51 is positioned on the developing frame 29, a space is formed between the developing frame 29 and the non-driving side bearing 51. The space is formed by the injection recess 29 and the injection path 51. The axial direction of the injection path 51d coincides with the axial direction of the injection recess 29f of the developing frame 29 and is aligned with the injection path 51d and the injection recess 29f in order from the upstream side in the arrow Q direction. At this time, the resin outlet 51g on the downstream side in the arrow Q direction of the injection path 51d is in the injection recess 29f in the arrow Q direction with respect to the abutment surface of the developing frame body side long abutment surface 29e and the non-drive side bearing longitudinal abutment surface 52c. Only a depth X is inserted in. Further, the distance T between the resin outlet outer 51h on the outer wall of the resin outlet 51g and the inner surface of the injection recess 29f is the width R between the bottom 52a of the screw 52 and the inner surface of the injection recess 29f, or the first restricting portion 52b of the screw 52. It is installed so as to be smaller than the width S with the inner surface of the injection recess 29f.

  As shown in FIG. 1, after fixing the developing blade 31 to the developing frame 29 with screws 52, molten resin is injected in the arrow Q direction from the resin injection port 51f on the upstream side in the arrow Q direction of the injection path 51d. Then, the molten resin passes through the injection path 51d, and further, between the bottom 52a of the screw 52 and the inner surface of the injection recess 29f (width R portion), between the first regulating portion 52b of the screw 52 and the inner surface of the injection recess 29f. It passes through (width S part) and fills the injection path 51d and the injection recess 29f. At this time, the second restricting portion 51i and the molten resin are in close contact with each other in the injection path 51d, and the first restricting portion 52b and the molten resin are in close contact within the injecting recess 29f. Further, the molten resin passes between the resin outlet exterior 51h and the inner surface of the injection recess 29f (width T portion), and is provided between the notch 29g and the developing frame 29 and the non-driving side bearing 51. 55, and a part of the buffer unit 55 is filled. Even if there is a variation in the amount of molten resin injected or a variation in molding of the injection path 51d and the injection recess 29f, the injection path 51d and the injection recess 29f are reliably filled. Therefore, an amount of molten resin larger than the amount satisfying the maximum volume of the injection path 51d and the injection recess 29f is caused to flow through the injection path 51d and the injection recess 29f. The buffer portion 55 has a volume in which excess molten resin can be accommodated, and the molten resin does not leak from the buffer portion 55. Further, the space between the bottom 52a of the screw 52 and the inner surface of the injection recess 29f (width R portion) and the space between the first restricting portion 52b of the screw 52 and the inner surface of the injection recess 29f (width S portion) It is wider than the space between the inner surface of the injection recess 29f (width T portion). Therefore, the molten resin flows into the width R portion and the width S portion before the width T portion. Therefore, the molten resin does not pass through the width T portion and fill the buffer portion 55 before passing through the width R portion and the width S portion and filling the injection path 51d and the injection recess 29f. Further, since the developing frame side longitudinal abutting surface 29e and the non-driving side bearing longitudinal abutting surface 52c are in contact with each other, the molten resin 54 does not leak to other portions.

  When the molten resin filling the injection path 51d and the injection recess 29f is cooled and solidified to become the resin molded portion 54, the second restricting portion 51i and the first locked portion 54a of the resin molded portion 54 are in close contact with each other, and the non-driving side bearing 51 is restricted from moving in the direction of arrow V in FIG. Similarly, the first restricting portion 52b and the second locked portion 54b of the resin molding portion 54 are in close contact with each other, and the development frame 29 is restricted from moving in the direction of arrow Q in FIG. . Accordingly, the non-driving side bearing 51 cannot move in the direction of arrow V in FIG. 1 with respect to the developing device frame 29 and is coupled to the developing device frame 29.

  The resin used as the resin molding part 54 is polyacetal (POM), which melts at about 190 ° C. to 210 ° C. and solidifies when cooled. The material of the developing frame 29 of the first frame and the non-driving side bearing 51 of the second frame is polystyrene (HIPS). Since polystyrene (HIPS) is not compatible with the polyacetal (POM) of the resin molding part 54, no bonding force is generated between the resin molding part 54 and the developing frame 29, the molten resin 54 and the non-driving side bearing 51. . In the present invention, the coupling can be maintained without separating the non-driving side bearing 51 and the developing frame 29 by the second regulating portion 51i and the first regulating portion 52b. In the present embodiment, polyacetal (POM) is used for the resin molding portion 54 and polystyrene (HIPS) is used for the first frame and the second frame, but other resins may be used. Further, when the material used for the resin molded portion 54 and the material used for the first and second frames are compatible, the first frame and the second frame can be made stronger by using the configuration of the present invention. Can be fixed.

  As described above, the non-driving side bearing 51 is fixed to the developing frame 29 by bringing the resin molding portion 54 into close contact with the screw 52 that fixes the developing blade 31 to the developing frame 29. In this method, a conventional space for fixing the non-driving side bearing 51 to the developing frame 29 (screw fixing space or a conventional resin bonding space) and a fixing blade 31 for fixing the developing blade 31 to the developing frame 29 are provided. There is no need to provide separate spaces. Therefore, a smaller developing device or process cartridge can be provided.

  Also in the drum unit 8, the first frame body can be the cleaning frame body 26, the second frame body can be the cartridge cover members 24 and 25, and the cleaning blade 7 as a cleaning member can be used instead of the developing blade. Accordingly, the configuration is not limited to fixing the developing frame 29 and the non-driving side bearing 51.

4 Electrophotographic photoreceptor (photoreceptor drum)
6 Developing roller 7 Cleaning blade 8 Drum unit 9 Developing unit 24 Drive side cartridge cover member 24a Support hole 25 Non-drive side cartridge cover member 25a Support hole 26 Cleaning frame 27 Waste developer storage 29 Development frame (first frame) body)
29a Non-driving side blade fixing hole 29b Driving side blade fixing hole 29c Positioning hole 29d Rotation stop hole 29e Development frame side longitudinal abutting surface 29f Injection recess 29g Notch 31 Developing blade 31a Thin sheet metal 31b Base sheet metal 32 Developer cover member 49 …… Developer storage 50 Driving bearing 51 Non-driving bearing (second frame)
51a Positioning boss 51b Anti-rotation boss 51d Injection path 51e Support hole 51f Resin injection port 51i Second restriction part 52, 53 Screw (fixing member)
52b First restriction portion 54 Resin molding portion 54a First locked portion 54b Second locked portion P Process cartridge

Claims (9)

A developing device used in an image forming apparatus,
A developer carrying member carrying the developer;
A developer regulating member that regulates the amount of developer carried on the developer carrying body;
A first frame that supports the developer regulating member;
A fixing member for fixing the developer regulating member to the first frame;
A second frame for supporting the developer carrier;
A resin molding part formed by injecting molten resin into a space formed by the first frame body and the second frame body, the first restricting part of the fixing member protruding into the space, and the A resin molded portion that engages with a second restricting portion provided on the second frame, and connects the first frame and the second frame;
A developing device.   The second frame has an injection port through which molten resin is injected into the space, and the second restricting portion faces upstream in the injection direction in which the molten resin is injected from the injection port. The developing device according to claim 1.   The developing device according to claim 1, wherein the fixing member is attached to a through hole connected to the space.   The developing device according to claim 1, wherein the fixing member is a screw. A process cartridge that can be attached to and detached from the main body of the image forming apparatus,
A photosensitive drum;
A developing device according to any one of claims 1 to 4,
A process cartridge. A process cartridge that can be attached to and detached from the main body of the image forming apparatus,
A photosensitive drum;
A cleaning member for removing the developer from the photosensitive drum;
A first frame that supports the cleaning member;
A fixing member for fixing the cleaning member to the first frame;
A second frame for supporting the photosensitive drum;
A resin molding part formed by injecting molten resin into a space formed by the first frame body and the second frame body, the first restricting part of the fixing member protruding into the space, and the A resin molded portion that engages with a second restricting portion provided on the second frame, and connects the first frame and the second frame;
A process cartridge.   The second frame has an injection port through which molten resin is injected into the space, and the second restricting portion faces upstream in the injection direction in which the molten resin is injected from the injection port. The process cartridge according to claim 6.   The process cartridge according to claim 6, wherein the fixing member is attached to a through hole connected to the space.   The process cartridge according to claim 6, wherein the fixing member is a screw.

Images