JP5553576B2 - Developer cartridge - Google Patents

Description

  The present invention relates to a developing cartridge that can be attached to and detached from an image forming apparatus such as an electrophotographic copying machine, a printer, or a facsimile.

  Here, the developing cartridge includes at least a developer carrying member that carries and conveys a developer for developing an electrostatic latent image formed on an image carrying member that is an electrophotographic photosensitive member. It is detachable from the apparatus main body.

  In image forming apparatuses such as electrophotographic copying machines, printers, and facsimiles, an electrostatic latent image formed on a drum-shaped electrophotographic photosensitive member (hereinafter referred to as “photosensitive drum”) as an image carrier is It is visualized as a toner image by developing with the developing means.

  2. Description of the Related Art Conventionally, a developing cartridge as a developing unit of an image forming apparatus using an electrophotographic image forming process includes a toner storage unit that stores a developer (hereinafter referred to as “toner”). The developing cartridge carries a developer in a toner storage portion and conveys it to develop a latent electrostatic image formed on the photosensitive drum (hereinafter referred to as “developing roller”). ). These members are integrally formed into a cartridge that can be attached to and detached from the main body of the image forming apparatus.

  In such a detachable developing cartridge, the user replaces the developing cartridge. At this time, it is common to take out the developing cartridge from the image forming apparatus main body and replace it with a new developing cartridge.

  Here, a cover member for protecting the developing roller is attached to the new developing cartridge. When a new developing cartridge is attached to the image forming apparatus body, the cover member is removed and attached to the image forming apparatus body.

  Further, the removed cover member can be attached to a used developing cartridge removed from the main body of the image forming apparatus, and the developing cartridge and the cover member can be simultaneously collected and recycled.

  As a cover member that is attached to the developing cartridge and protects the developing roller, a configuration disclosed in Patent Document 1 shown below is known.

JP 2003-173076 A

  If the removed cover member is attached to a used developing cartridge taken out from the main body of the image forming apparatus and can be collected for reuse of the parts of the developing cartridge, limited resources can be effectively used.

  Further, when the developer cartridge is transported for reuse, it is necessary to prevent the developing roller surface exposed from the developer cartridge from being damaged. For this reason, it is desirable to return the cover member that covers the surface of the developing roller attached to the new developing cartridge to the user.

  The cover member of the conventional example covers the entire developing roller exposed from the developing cartridge and is removable. A plurality of engaging portions between the developing cartridge and the cover member are arranged with respect to the developing roller in the axial direction of the developing roller (that is, in the longitudinal direction of the developing roller) or in the longitudinal direction. For this reason, in order for the user to attach the cover member to the used developing cartridge, it is necessary to attach the engaging portion correctly in the same state as when the cover member is attached to the new developing cartridge. Therefore, there is a possibility that the cover member cannot be easily attached to the developing cartridge for the user.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a developing cartridge having a developing cartridge and a cover member that can be attached to and detached from the developing cartridge, and has a cover member with good recyclability and usability.

The above object is achieved by the developing cartridge according to the present invention. In summary, the present invention is a developing cartridge that is detachable from an electrophotographic image forming apparatus that forms an image on a recording medium,
(A) a developer carrier for developing the latent image formed on the image carrier;
(B) a frame body having a notch in the longitudinal center of the frame body, and a first engagement provided direction odor Te on one end side that intersects the axial direction of said developer carrying member A frame body comprising a portion and a second engaged portion provided at the notch position on the other end side;
(C) A cover member detachably attached to the frame body for covering the exposed portion of the developer carrying body exposed from the frame body, the first engagement portion and the second engagement portion. A cover member having a joint part;
Have
The cover member is configured such that the first engaging portion engages with the first engaged portion, the second engaging portion engages with the second engaged portion, and the frame member The first state to be attached, the first engaging portion engages with the second engaged portion, the second engaging portion engages with the first engaged portion, and the frame body The developing cartridge can be in a second state attached to the developing cartridge.

  According to the present invention, the first engaged portion and the second engaged portion are arranged near the center in the longitudinal direction of the developing cartridge, and the engaging portion of the cover member is not engaged with the direction of the cover member. To be attached to the developing cartridge at the same time. Therefore, when the user stores or returns the used developing cartridge, the cover member can be easily attached. Therefore, the entire area of the developing roller exposed from the developing cartridge can be protected, and both usability and recyclability of the developing cartridge parts can be achieved.

1 is a schematic cross-sectional view of an embodiment of an image forming apparatus to which a developing cartridge according to the present invention can be detachably mounted. 1 is an external perspective view of an embodiment of a developing cartridge according to the present invention. FIG. 2 is a schematic cross-sectional view illustrating a state during image formation of the image forming apparatus illustrated in FIG. 1. FIG. 4A is a schematic cross-sectional view of the developing cartridge according to the present invention, FIG. 4A shows a state where a cover member is mounted, and FIG. 4B shows a state where the cover member is removed. FIG. 5A is a schematic perspective view of the developing roller, and FIG. 5B is a diagram for explaining a manner of attaching the developing roller to the developing cartridge. FIG. 6A is a perspective view of the developing cartridge and the cover member according to the present invention, FIG. 6A shows a state where the cover member is mounted, and FIG. 6B shows a state where the cover member is removed. FIG. 2 is a schematic cross-sectional view showing the developing cartridge with the cover member according to the present invention attached thereto. FIG. 8A is a perspective view showing a state in which the developing cartridge according to the present invention is mounted on the rotary, and FIG. 8B is a partial cross-sectional view of the rotary. FIG. 9A is a schematic cross-sectional view showing a state in which the cover member is attached to the developing cartridge according to the present invention while being rotated 180 degrees, and FIG. 9B is a perspective view of the developing cartridge.

  Hereinafter, the developing cartridge according to the present invention will be described in more detail with reference to the drawings.

Example 1
FIG. 1 shows an embodiment of a so-called rotary type color electrophotographic image forming apparatus provided with a rotary capable of mounting a plurality of developing cartridges according to the present invention.

(Overall configuration of image forming apparatus)
First, the overall configuration of the image forming apparatus and the image forming operation will be described with reference to FIG.

  In this embodiment, the image forming apparatus 11 is a four-color full-color laser beam printer, and FIG. 1 is a cross-sectional view showing a schematic configuration thereof.

  As shown in FIG. 1, the image forming apparatus 11 includes a drum-shaped electrophotographic photosensitive member, that is, a photosensitive drum 3a as an image carrier. Around the photosensitive drum 3a, there are charging means 3b for uniformly charging the photosensitive drum 3a and exposure means 12 for irradiating the photosensitive drum 3a with laser light to form a latent image. Has been placed. Further, a plurality of developing cartridges as developing means for developing the latent image formed on the photosensitive drum 3a adjacent to the photosensitive drum 3a with a corresponding color developer (that is, toner) to visualize the latent image. 5 is arranged. In this embodiment, the plurality of developing cartridges 5 are a yellow developing cartridge 5a, a magenta developing cartridge 5b, a cyan developing cartridge 5c, and a black developing cartridge 5d. Around the photosensitive drum 3a, a cleaning means 3c for removing residual toner on the photosensitive dome 3a is disposed.

  In this embodiment, the photosensitive drum 3a, the charging unit 3b, and the cleaning unit 3c are integrally formed, and the drum cartridge 3 that can be attached to and detached from the image forming apparatus main body 11A is configured.

  Each of the yellow developing cartridge 5a, the magenta developing cartridge 5b, the cyan developing cartridge 5c, and the black developing cartridge 5d includes a developer carrier, that is, a developing roller 2 (2a, 2b, 2c, and 2d). The developing cartridge 5 (5a, 5b, 5c, 5d) is held by a rotary 101 that is rotatably attached to the apparatus main body 11A.

  The configuration in which the rotary 101 holds the yellow developing cartridge 5a, the magenta developing cartridge 5b, the cyan developing cartridge 5c, and the black developing cartridge 5d is the same. Therefore, the description of the configuration in which the rotary 101 in the present embodiment holds each developing cartridge will be made with respect to the yellow developing cartridge 5a.

  When the yellow developing cartridge 5a is mounted on the rotary 101, the locked portion 6a (FIG. 2) provided on the yellow developing cartridge 5a is connected to the developing cartridge locking member 103a (FIG. 1) provided on the rotary 101. Engage. Thus, the yellow developing cartridge 5a is supported by the rotary 101. The developing cartridge locking member 103a is engaged with the yellow developing cartridge 5a by a spring (not shown) and restricts movement in the direction of arrow D in FIG.

  In the same manner as the yellow developing cartridge 5a, the magenta developing cartridge 5b, the cyan developing cartridge 5c, and the black developing cartridge 5d are similarly supported by the rotary 101 by the developing cartridge locking members 103b, 103c, and 103d.

  The image forming operation will be described below.

  First, the photosensitive drum 3a is rotated in the direction of arrow A in FIG. In synchronization with the rotation of the photosensitive drum 3a, the intermediate transfer belt 13 is rotated in the direction of arrow C in FIG. The surface of the photosensitive drum 3a is uniformly charged by the charging unit 3b, and the exposure unit 12 irradiates the yellow image with light to form a yellow electrostatic latent image on the photosensitive drum 3a.

  Simultaneously with the formation of the electrostatic latent image, the rotary 101 that holds the developing cartridge 5 (5a, 5b, 5c, 5d) and is rotatable is connected to the image forming apparatus 11 around the rotary rotation shaft 101a. The drive transmission mechanism 22 provided rotates in the direction of arrow B in FIG.

  As a result, the rotary 101 rotates to place the yellow developing cartridge 5a at the developing position facing the photosensitive drum 3a as shown in FIG.

  Then, a potential difference is provided between the photosensitive drum 3a and the developing roller 2a so that the yellow developer adheres to the latent image formed on the photosensitive drum 3a. Thus, development is performed by attaching a yellow developer to the latent image formed on the photosensitive drum 3a. That is, a yellow toner image is formed on the photosensitive drum 3a.

  Thereafter, a voltage having a polarity opposite to that of the toner is applied to the primary transfer roller 14 disposed inside the intermediate transfer belt 13 to primarily transfer the yellow toner image on the photosensitive drum 3 a onto the intermediate transfer belt 13. .

  When the primary transfer of the yellow toner image is completed as described above, the rotary 101 receives driving from the drive transmission mechanism 22 of the image forming apparatus 11 and rotates in the direction of arrow B in FIG. Then, the magenta developing cartridge 5b, the cyan developing cartridge 5c, and the black developing cartridge 5d are sequentially positioned at the developing position facing the photosensitive drum 3a. As in the case of yellow, electrostatic latent image formation, development, and primary transfer are sequentially performed for magenta, cyan, and black, and four color toner images are superimposed on the intermediate transfer belt 13.

  Meanwhile, as shown in FIG. 1, the secondary transfer roller 15 is not in contact with the intermediate transfer belt 13. The cleaning unit 16 for the intermediate transfer belt 13 is also in a non-contact state with the intermediate transfer belt 13.

  On the other hand, a toner image transfer body in this embodiment, that is, a sheet 110 as a recording medium, is stacked and stored in a paper feed cassette 17 provided at a lower portion of the image forming apparatus. The sheets are separated and fed one by one from 17, and sent to the conveying roller 19. The conveyance roller 19 sends out the sheet 110 between the intermediate transfer belt 13 and the secondary transfer roller 15. Here, as shown in FIG. 3, the secondary transfer roller 15 is in pressure contact with the intermediate transfer belt 13.

  Further, a voltage having a polarity opposite to that of the toner is applied to the secondary transfer roller 15, and the four-color toner images superimposed on the intermediate transfer belt 13 are secondarily applied to the surface of the conveyed sheet 110. It will be transcribed.

  The sheet 110 to which the toner image is transferred is sent to the fixing device 20. In the fixing device 20, heat and pressure are applied to the sheet 110 to fix the toner image on the sheet 110. Thereafter, the sheet 110 is discharged from the fixing device 20 to the paper discharge unit 21 outside the image forming apparatus 11.

(Description of developing cartridge)
The configurations of the yellow developing cartridge 5a, the magenta developing cartridge 5b, the cyan developing cartridge 5c, and the black developing cartridge 5d are all the same. Therefore, the description of the configuration of the developing cartridge in the present embodiment will be made on the yellow developing cartridge 5a. The yellow developing cartridge 5a of this embodiment will be described with reference to FIGS. 4 (a) and 4 (b) and FIGS. 5 (a) and 5 (b).

  4A and 4B are vertical sectional views that intersect with the longitudinal direction of the yellow developing cartridge 5a of this embodiment, that is, the longitudinal direction passing through the handle 31a provided near the center in the axial direction. It is.

  The yellow developing cartridge 5a has a developing frame 5aA. The developing frame 5aA forms a developing container 7a as a toner storage unit for storing a developer (toner), and rotatably holds the developing roller 2a for carrying the toner and the like so as to be unitized integrally. ing. The developing container 7a of the yellow developing cartridge 5a is separated into a toner storage chamber 7a1 and a developing chamber 7a2 having a developing roller 2a and a toner supply roller 8a, both of which are connected by a toner supply opening 7a3.

  The developing roller outer periphery 2a3 of the developing roller 2a and the toner supply roller outer periphery 8a3 of the toner supply roller 8a are disposed so as to contact with each other in the developing chamber 7a2.

  As shown in FIG. 5A, the developing roller 2a includes a rubber roller portion 2a1 and a rigid shaft 2a2. The rigid shaft 2a2 passes through the rubber roller portion 2a1 in the direction of the rotation axis of the developing roller 2a, and both ends are rubber rollers. Projecting portions 2a2L and 2a2R projecting from the portion 2a1 are formed.

  A configuration in which the yellow developing cartridge 5a rotatably supports the developing roller 2a on the frame 5aA will be described with reference to FIG.

  In this embodiment, the yellow developing cartridge 5a rotatably holds the developing roller 2a by side members 6L and 6R that are provided on both sides of the frame 5aA and hold the projecting portions 2a2L and 2a2R of the developing roller 2a, respectively. ing.

  In this embodiment, when the yellow developing cartridge 5a reaches the user's hand, as shown in FIG. 4A, a film-like toner seal 9a is thermally welded to the toner supply opening 7a3. Etc., and is fixed to the developing container 7a. Thereby, the toner storage chamber 7a1 and the developing chamber 7a2 are separated. By removing the toner seal 9a before use, the toner 10a in the toner storage chamber 7a1 can be supplied into the developing chamber 7a2 as shown in FIG. 4B.

  Further, as understood from FIG. 4B, a part of the outer periphery 2a3 of the developing roller 2a is exposed to the yellow developing cartridge 5a and directly touches the user's hand. Therefore, as shown in FIG. 4A, a cover member 30a that covers the entire exposed portion of the outer periphery 2a3 of the rubber roller is provided in an unused state. By removing the cover member 30a, the outer periphery 2a3 of the rubber roller is exposed and contacts the photosensitive drum 3a in the image forming apparatus 11 as shown in FIG.

  In FIG. 4B, the toner 10a in the developing chamber 7a2 is supplied to the toner supply roller 8a, and the toner supply roller 8a rotates in the direction of arrow E in FIG. Toner 10a is supplied. The developing roller 2a rotates in the direction of arrow F in FIG. 4B, and the toner 10a on the developing roller 2a is regulated by the developing blade 1a. The toner is developed at a position where the developing roller 2a and the photosensitive drum 3a face each other. Thereafter, the toner 10a remaining on the developing roller 2a is removed by the toner supply roller 8a and supplied with toner. A voltage is supplied from the image forming apparatus 11 to the developing roller 2a in order to provide a potential difference from the photosensitive drum 3a. A voltage is also supplied from the image forming apparatus 11 to the toner supply roller 8a.

(Configuration of engagement between cover member and developing cartridge)
A configuration of engagement between the cover member and the developing cartridge 5 will be described with reference to FIGS. 6A, 6B, 7 and 8A, 8B. The engagement structure of the cover member and the developing cartridge is the same in the other developing cartridges, that is, the magenta developing cartridge 5b, the cyan developing cartridge 5c, and the black developing cartridge 5d. Therefore, the description of the configuration of the cover member and the developing cartridge 5 in this embodiment will be made with the yellow developing cartridge 5a and the cover member 30a attached to the yellow developing cartridge 5a.

  FIG. 6A is a perspective view showing a state in which the cover member 30a is attached to the yellow developing cartridge 5a. FIG. 6B is a perspective view showing a state in which the cover member 30a is detached from the yellow developing cartridge 5a. FIG. 7 is a vertical cross-sectional view intersecting the longitudinal direction passing through the handle 31a provided in the vicinity of the center of the longitudinal direction of the yellow developing cartridge 5a (arrow R in FIG. 6A). FIG. 8A is a perspective view showing a state where the developing cartridge 5 is mounted on the rotary 101. FIG. 8B is a schematic cross-sectional view showing a state where the developing cartridge 5 is mounted on the rotary 101.

  The yellow developing cartridge 5a includes a handle engaged portion (first engaged portion) 31a1 provided in a handle 31a near the center in the longitudinal direction, as shown in FIGS. 6B and 7, and a developer container 7a. The two parts of the container engaged portion (second engaged portion) 7a4 thus engaged are engaged with the cover member 30a.

  Here, as shown in FIGS. 8A and 8B, the container engaged portion 7a4 is located at a position facing the handle 31d of the black developing cartridge 5d adjacent to the yellow developing cartridge 5a mounted on the rotary 101. Has been placed. That is, it is located near the center of the longitudinal direction of the developing cartridge 5a, and is further provided at a position where the surfaces 7a5 and 7a6 of the developing container 7a which is the frame 5aA are cut out.

  This is for improving the operability of the adjacent developing cartridges 5d in a state where a plurality of developing cartridges 5 are mounted on the apparatus main body 11A as shown in FIG. 8B. That is, when the handle 31d is gripped to operate the developing cartridge 5d, the adjacent container engaged portion 7a4 is separated from the handle 31d and the space M is provided in order to improve gripping performance. Since the present embodiment is a rotary type image forming apparatus, it is in the above-described form in consideration of usability.

  Next, the cover member 30a will be described.

  As shown in FIGS. 6B and 7, the cover member 30a is engaged with the yellow developing cartridge 5a by four engaging portions 30a1, 30a2, 30a3, and 30a4 provided near the center in the longitudinal direction. .

  That is, the yellow developing cartridge 5a has a handle engaged portion 31a1 on one end side of the frame 5aA and a container engaged on the other end side in a direction crossing the longitudinal direction (that is, the axial direction) of the developing roller 2a. Part 7a4 is formed. The engagement portions formed on the cover member 30a, that is, the engagement portions (first engagement portions) 30a1 and 30a2 of the cover member 30a are the handle engagement portion 31a1 and the engagement portion (second engagement portion). ) 30a3 and 30a4 are simultaneously engaged with the container engaged portion 7a4 of the developing container 7a. Thereby, the cover member 30a is attached to the developing cartridge 5a (FIG. 6A). At this time, the surface 30a5 of the cover member 30a is provided so as not to contact the developing roller 2a.

  Further, the cover member 30a engages with the engaged portions corresponding to the respective engaging portions described above, but the engaging portions 30a1 and 30a2 are connected to the container cover as shown in FIGS. 9 (a) and 9 (b). The engaging portion 7a4 and the engaging portions 30a3 and 30a4 can be engaged with the handle engaged portion 31a1 at the same time. That is, the cover member 30a can be attached to the yellow developing cartridge 5a even when the cover member 30a is rotated 180 degrees.

  That is, according to the present invention, in the cover member 30a, the first engagement portions 30a1 and 30a2 are engaged with the first engaged portion 31a1, and the second engagement portions 30a3 and 30a4 are the second engaged portion 7a4. The first state of being attached to the frame 5aA can be taken. On the other hand, in the cover member 30a, the first engaging portions 30a1 and 30a2 are engaged with the second engaged portion 7a4, and the second engaging portions 30a3 and 30a4 are engaged with the first engaged portion 31a1. Thus, the second state of being attached to the frame 5aA can be obtained.

  This is because the handle engaging portion (second engaged portion) 31 a 1 and the developer container engaged portion (second portion) that forms a space M for improving the gripability of the handle 31 in the image forming apparatus 11. This is because the engaged portion) 7a4 is disposed at the same position in the longitudinal direction. Further, even when the cover member 30a is attached to the yellow developing cartridge 5a with the cover member 30a rotated 180 degrees, the cover member surface 7a5 is provided so as not to contact the developing roller 2a. It is in. Therefore, it is possible to protect the entire area of the developing roller exposed from the developing container 7a, that is, the frame 5aA, regardless of the mounting direction of the cover member 30a.

  As described above, in the developing cartridge 5 of the present embodiment, the handle engaged portion 31a1 and the container engaged portion 7a4 are arranged near the center in the longitudinal direction of the developing cartridge 5. As a result, the cover member 30a can be engaged with the engaged portions 31a1, 7a4 at the same time and attached to the developing cartridge 5 regardless of the direction of the cover member 30a.

  Therefore, when the user stores or returns the used developing cartridge 5, the cover member 30a can be easily attached. Therefore, the entire developing roller exposed from the developing cartridge 5 can be protected, and both usability and recyclability of the developing cartridge parts can be achieved.

  Although the yellow developing cartridge 5a has been described in the above embodiment, the same applies to the other developing cartridges 5b, 5c, and 5d of magenta, cyan, and black.

  In the above-described embodiments, the case of the color developing cartridge used in the rotary type electronic image forming apparatus has been described. However, the present invention is not limited to this, and the developing cartridge and the monochrome developing cartridge in the case of the inline type are also illustrated. Applicable.

2 (2a to 2d) Developing roller (developer carrier)
3a Photosensitive drum (image carrier)
5 (5a to 5d) Developing cartridge 5aA Developing frame 7a4 Container locking portion (second engaged portion)
11 Image forming apparatus 11A Image forming apparatus main body 30a Cover members 30a1, 30a2 Engagement part (first engagement part)
30a3, 30a4 engagement part (second engagement part)
31a Handle 31a1 Handle engaged portion (first engaged portion)
101 Rotary 110 sheet (recording medium)
M space R Development cartridge longitudinal direction (axial direction)

Claims (4)

A developing cartridge detachable from an electrophotographic image forming apparatus for forming an image on a recording medium,
(A) a developer carrier for developing the latent image formed on the image carrier;
(B) a frame body having a notch in the longitudinal center of the frame body, and a first engagement provided direction odor Te on one end side that intersects the axial direction of said developer carrying member A frame body comprising a portion and a second engaged portion provided at the notch position on the other end side;
(C) A cover member detachably attached to the frame body for covering the exposed portion of the developer carrying body exposed from the frame body, the first engagement portion and the second engagement portion. A cover member having a joint part;
Have
The cover member is configured such that the first engaging portion engages with the first engaged portion, the second engaging portion engages with the second engaged portion, and the frame member The first state to be attached, the first engaging portion engages with the second engaged portion, the second engaging portion engages with the first engaged portion, and the frame body And a second state of being attached to the developing cartridge.   The developing cartridge according to claim 1, wherein the first engaged portion is provided on a handle provided on the frame body for gripping the developing cartridge.   The second engaged portion is a handle provided on the adjacent developing cartridge to grip the adjacent developing cartridge when a plurality of the developing cartridges are mounted on the apparatus main body of the electrophotographic image forming apparatus. The developing cartridge according to claim 1, wherein the developing cartridge is provided at a position opposed to the developing cartridge. 4. The developing cartridge according to claim 1, wherein the first engaged portion and the second engaged portion are arranged in a center in a longitudinal direction of the frame body. 5. .

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