JP7076945B2 - Developing equipment and image forming equipment - Google Patents

Description

The present invention relates to an image forming apparatus using an electrophotographic image forming method (electrophotographic process) and a developing apparatus used for the image forming apparatus.

Here, the image forming apparatus forms an image on a recording material (recording medium) by using an electrophotographic process. Examples of the image forming apparatus include printers (laser beam printers, LED printers, etc.), copiers, facsimile machines, word processors, and multifunction printers thereof.

Further, the developing device is a device for developing an electrostatic latent image formed on an electrophotographic photosensitive drum (hereinafter, referred to as “photoreceptor”) as an image carrier with a developer. The developing apparatus is composed of a developing means, a developing frame body that supports the developing means, parts related to the developing means, and the like. Examples of the developing means include a developing roller as a developing agent carrier and a developing blade as a developing agent regulating member.

In an image forming apparatus such as a printer using an electrophotographic process, the photoconductor is uniformly charged. Then, by selectively exposing the charged photoconductor, an electrostatic latent image is formed on the photoconductor. Next, the electrostatic latent image formed on the photoconductor is visualized as a toner image with toner as a developer. Then, the toner image formed on the photoconductor is transferred to a recording material such as recording paper or a plastic sheet, and heat or pressure is applied to the toner image transferred on the recording material to convert the toner image into a recording material. Image recording is performed by fixing.

Such image forming apparatus generally requires maintenance of various process means used in the electrophotographic process. Examples of process means include charging means, developing means and cleaning means acting on the photoconductor. In order to facilitate the maintenance of these various process means, a method has been put into practical use in which a photoconductor, a charging means, a developing means, a cleaning means, and the like are collectively made into a cartridge and attached to and detached from the image forming apparatus main body. According to this cartridge method, it is possible to provide an image forming apparatus having excellent usability.

Further, as the cartridge, a drum cartridge having a photosensitive drum, a developing cartridge as a developing device having a developing means, a toner cartridge for supplying a developing agent, and the like are known.

Here, as in Patent Document 1, there is a development cartridge configured by a developing unit that rotatably supports a developing roller and a frame that rotatably supports both ends of the developing unit. .. According to this, when the frame is positioned on the main body of the image forming apparatus, the developing unit rotates, and the developing roller can come into contact with and separate from the photosensitive drum.

Japanese Unexamined Patent Publication No. 2013-182036

The present invention is a further development of the conventional configuration described above.

In the above-described configuration, if the position of the center of rotation of the developing unit is displaced, the stability of contact of the developing roller as the developing agent carrier with respect to the photosensitive drum as the image carrier may be affected.

In order to achieve the above object, one of the configurations of the invention according to the present application is as follows.

A developing unit including a developer carrier that supplies a developer to an image carrier that supports an electrostatic latent image, and a developing frame that supports the developer carrier.
An end support member that rotatably supports the developing unit on one end side in the axial direction of the developing agent carrier, and an end supporting member.
On the other end side in the axial direction, the other end support member that rotatably supports the developing unit and
The first axis provided in the developing unit and
A second shaft provided on either the developing unit or the other end support member, and
A first hole provided in the end support member that supports the first shaft so that the developing unit rotates about the first shaft and the second shaft. And a first hole configured to allow the first axis to move in a direction intersecting the axis direction.
A second hole provided in either the other of the developing unit or the other end support member so that the developing unit rotates about the first axis and the second axis. A second hole that supports the second axis and is configured to restrict the movement of the second axis in a direction intersecting the axial direction.
An urging member that urges the first axis in a direction intersecting the axis direction,
It is a developing device equipped with
The developing device is configured to be detachably attached to and attached to the image forming device separately from the image carrier.
The end support member and the other end support member are developing devices that can rotate independently of the developing unit.

As described above, according to the present invention, it is possible to improve the stability of contact of the developing roller as the developer carrier with respect to the photosensitive drum as the image carrier.

The figure explaining the developing apparatus which concerns on Example 1 (a) when the alignment of the developing unit is misaligned (b) when the developing unit is in a normal position. Schematic diagram of the electrophotographic image forming apparatus according to the first embodiment. Explanatory drawing of the drum cartridge according to the first embodiment Sectional drawing of the drum cartridge which concerns on Example 1. Sectional drawing of the developing apparatus which concerns on Example 1. Installation explanatory view of the drum cartridge and the developing device according to the first embodiment The figure explaining the developing apparatus which concerns on Example 1. The figure explaining the support hole which concerns on Example 1. Explanatory drawing which shows the state which the developing apparatus which concerns on Example 1 is positioned on the image forming apparatus main body. The figure which shows the structure which omitted the other end support member in the developing apparatus which concerns on Example 1. The figure explaining the developing apparatus which concerns on Example 2 (a) when the development unit is out of alignment (b) when the developing unit is in a normal position. The figure explaining the developing apparatus which concerns on Example 2. Explanatory drawing which shows the state which the developing apparatus which concerns on Example 2 is positioned in the image forming apparatus main body. The figure explaining the assembly of the developing apparatus which concerns on Example 2. Diagram illustrating the first hole and the second hole The figure explaining the structure of the first hole The figure explaining the unit urging member Schematic diagram illustrating misalignment The figure explaining the arrangement of the urging member Sectional drawing explaining the developing apparatus which concerns on Example 3. The figure explaining the developing apparatus which concerns on Example 3 (a) when the development unit is out of alignment (b) when the developing unit is in a normal position. Schematic diagram illustrating the alignment misalignment according to the third embodiment Schematic diagram illustrating the urging member according to the third embodiment

[Example 1]
(Overall configuration of image forming device)
First, the overall configuration of the apparatus main body 100 of the electrophotographic image forming apparatus (hereinafter referred to as an image forming apparatus) will be described with reference to FIG. As shown in FIG. 2, the apparatus main body 100 has four removable photosensitive drum cartridges (hereinafter referred to as drum cartridges) 9 (9Y, 9M, 9C, 9K) having a photosensitive drum as an image carrier. It is installed. Further, four developing devices (hereinafter referred to as development cartridges) 4 (4Y, 4M, 4C, 4K) are mounted on the device main body 100. The drum cartridge 9 and the developing cartridge 4 are detachably mounted on the apparatus main body 100 by a mounting member (not shown). Further, the drum cartridge 9 and the developing cartridge 4 are provided in the apparatus main body 100 so as to be inclined with respect to the horizontal direction.

Each drum cartridge 9 has a photosensitive drum 1 (1a, 1b, 1c, 1d). Then, process means such as a charging roller 2 (2a, 2b, 2c, 2d) as a charging member and a cleaning member 6 (6a, 6b, 6c, 6d) as a cleaning member are integrally formed around the photosensitive drum 1. Have been placed.

Further, each developing cartridge 4 (4Y, 4M, 4C, 4K) has a developing roller 25 (25a, 25b, 25c, 25d) as a developing agent carrier. Further, process means such as a developing blade 35 (35a, 35b, 35c, 35d) as a developing agent regulating member are integrally arranged.

The charging roller 2 uniformly charges the surface of the photosensitive drum 1. The developing roller 25 abuts on the photosensitive drum 1 and develops an electrostatic latent image formed on the photosensitive drum 1 with a developer (hereinafter referred to as toner) to form a visible image. Then, the cleaning member 6 removes the toner remaining on the photosensitive drum 1 after transferring the toner image formed on the photosensitive drum 1 to the recording medium S.

Further, in the apparatus main body 100, below the drum cartridge 9 and the developing cartridge 4, an exposure apparatus for selectively exposing the photosensitive drum 1 based on image information to form an electrostatic latent image on the photosensitive drum 1. The scanner unit 3 is provided.

A cassette 17 containing the recording medium S is mounted on the lower portion of the apparatus main body 100. A recording medium transport means is provided so that the recording medium S passes through the secondary transfer roller 69 and the fixing portion 74 and is transported above the apparatus main body 100. That is, the electrostatic latent image and recording formed on the feeding roller 54 that separates and feeds the recording media S in the cassette 17 one by one, the transport roller pair 76 that conveys the fed recording medium S, and the photosensitive drum 1. A resist roller pair 55 for synchronizing with the medium S is provided.

Further, above the drum cartridge 9 and the developing cartridge 4, an intermediate transfer unit 5 as an intermediate transfer means for transferring the toner image formed on each photosensitive drum 1 (1a, 1b, 1c, 1d) is provided. There is. The intermediate transfer unit 5 includes a drive roller 56, a driven roller 57, a primary transfer roller 58 (58a, 58b, 58c, 58d) at a position facing the photosensitive drum 1 of each color, and a roller facing the secondary transfer roller 69. Has 59. Then, a transfer belt 14 as an intermediate transfer body is hung. The transfer belt 14 circulates in the direction of arrow E so as to face and contact all the photosensitive drums 1. By applying a voltage to the primary transfer rollers 58 (58a, 58b, 58c, 58d), the primary transfer is performed from the photosensitive drum 1 onto the transfer belt 14. Then, a voltage is applied to the opposing roller 59 and the secondary transfer roller 69 arranged in the transfer belt 14, and the toner of the transfer belt 14 is transferred to the recording medium S.

At the time of image formation, each photosensitive drum 1 is rotated, and the scanner unit 3 selectively exposes the photosensitive drum 1 uniformly charged by the charging roller 2. As a result, an electrostatic latent image is formed on the photosensitive drum 1, and the electrostatic latent image is developed by the developing roller 25. As a result, each color toner image is formed on each photosensitive drum 1. In synchronization with this image formation, the resist roller pair 55 conveys the recording medium S to the secondary transfer position where the opposing roller 59 and the secondary transfer roller 69 are in contact with each other with the transfer belt 14 interposed therebetween. Then, by applying the transfer bias voltage to the secondary transfer roller 69, each color toner image on the transfer belt 14 is secondarily transferred to the recording medium S. As a result, a color image is formed on the recording medium S. The recording medium S on which the color image is formed is heated and pressurized by the fixing portion 74 to fix the toner image. After that, the recording medium S is discharged to the discharge unit 75 by the discharge roller 72. The fixing portion 74 is arranged on the upper part of the apparatus main body 100.

Further, below each developing cartridge 4, a unit urging member 80 (80a, 80b, 80c, 80d) is attached to the apparatus main body 100 in order to bring the developing roller 25 held by the developing cartridge 4 into contact with the photosensitive drum 1. It is provided.

(Drum cartridge)
Next, the drum cartridge 9 in this embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is a configuration explanatory diagram of the drum cartridge 9 (9Y, 9M, 9C, 9K). In this embodiment, 9Y, 9M, 9C, and 9K have the same configuration. Here, in the insertion direction of the drum cartridge 9 and the developing cartridge 4, which will be described later, the upstream side in the insertion direction is defined as the front side, and the downstream side is defined as the back side.

A photosensitive drum 1 is rotatably provided on the cleaning frame 27 of the drum cartridge 9 (9Y, 9M, 9C, 9K) via the drum front bearing 10 and the drum back bearing 11. A drum coupling 16 and a flange are provided on one end side of the photosensitive drum 1 in the axial direction.

FIG. 4 is a cross-sectional view of the drum cartridge 9. As described above, the charging roller 2 and the cleaning member 6 are provided around the photosensitive drum 1 that rotates in the direction of the arrow D in the figure. The cleaning member 6 is composed of a rubber blade 7 and a cleaning support member 8. The tip portion 7a of the rubber blade 7 is arranged so as to be in contact with the rotation direction of the photosensitive drum 1 in the counter direction. Then, the residual toner removed from the surface of the photosensitive drum 1 by the cleaning member 6 falls into the removing toner chamber 27a. Further, the sealing sheet 21 for preventing the removal toner from the removal toner chamber 27a from leaking is in contact with the photosensitive drum 1. Then, by transmitting the driving force of the main body driving motor (not shown), which is a driving source, to the drum coupling 16 of the drum cartridge 9, the photosensitive drum 1 is rotationally driven according to the image forming operation. The charging roller 2 is rotatably attached to the drum cartridge 9 via the charging roller bearing 28, is pressurized toward the photosensitive drum 1 by the charging roller pressurizing member 33, and is driven to rotate.

(Development cartridge)
Next, the developing cartridge 4 will be described with reference to FIG. FIG. 5 is a cross-sectional view of a developing cartridge 4 (4Y, 4M, 4C, 4K) in which toner is stored in the developing cartridge. In this embodiment, the development cartridge 4Y containing the yellow toner, the development cartridge 4M containing the magenta toner, the development cartridge 4C containing the cyan toner, and the development cartridge 4K containing the black toner are the same. It is a composition. Some of the development cartridges 4 may have different configurations.

The developing cartridge 4 includes a developing roller 25 described below and a developing unit 39 including a developing frame 31. The developing frame 31 rotatably supports the developing roller 25 that comes into contact with the photosensitive drum 1 and rotates in the direction of arrow B. Further, the developing frame 31 is provided with a toner supply roller 34 that rotates in contact with the developing roller 25, and a developing blade 35 for restricting the toner layer on the developing roller 25. The developing frame 31 is composed of a developing chamber 31c in which a developing roller 25 is arranged, and a toner accommodating chamber 31a provided below the developing chamber 31c. The developing chamber 31c and the toner accommodating chamber 31a are separated by a partition wall 31d. Further, the partition wall 31d is provided with an opening 31b through which the toner passes when the toner is conveyed from the toner accommodating chamber 31a to the developing chamber 31c. Further, the developing frame 31 is provided with an urged portion 31e urged by the unit urging member 80 (80a, 80b, 80c, 80d) (see FIG. 2) of the apparatus main body 100.

The developing roller 25 and the toner supply roller 34 are rotatably supported by the developing frame 31 via the developing back bearings 12 and the pre-developing bearings 13 provided on both sides of the developing roller 25 in the axial direction (see FIG. 7). ).

In the toner storage chamber 31a of the developing frame 31, the toner transporting member 36 is rotated in the direction of the arrow N in the drawing to stir the stored toner and to transport the toner to the developing chamber 31c through the opening 31b. Is provided.

In the developing cartridge 4 of the present embodiment, at the time of image formation, the center of rotation of the toner transporting member 36 is located below the lower opening portion 31b1 in the gravity direction of the opening 31b, and the center of the developing roller 25 is located below the opening lower portion 31b1. It is located above the lower side of the opening 31b1 in the direction of gravity. Then, the toner transport member 36 pumps up and supplies the toner from the toner accommodating chamber 31a provided below the developing chamber 31c to the developing chamber 31c.

(Structure in which a drum cartridge and a developing cartridge are inserted into an electrophotographic image forming apparatus)
Next, a configuration in which the drum cartridge 9 and the developing cartridge 4 are inserted into the apparatus main body 100 will be described with reference to FIG. The apparatus main body 100 is provided with a drum cartridge 9 and a mounting port 101 (101a, 101b, 101c, 101d) for mounting each developing cartridge 4. In the present embodiment, the drum cartridge 9 is attached to and detached from the mounting port 101 with the axial direction of the photosensitive drum 1 as the attachment / detachment direction. Further, the developing cartridge 4 is attached / detached to / from the mounting port 101 with the axial direction of the developing roller 25 as the attachment / detachment direction. That is, the drum cartridge 9 and the developing cartridge 4 are configured to be inserted from the front side to the back side. In the following description, this direction is referred to as the insertion direction F. Further, as shown in FIG. 6, the drum cartridge 9 and the developing cartridge 4 can be independently attached to and detached from the apparatus main body 100. That is, the developing cartridge 4 can be attached to and detached from the apparatus main body 100 provided with the photosensitive drum 1 on which the latent image is developed by the developing roller 25. Further, the developing cartridge 4 is removable with the drum cartridge 9 including the photosensitive drum 1 on which the latent image is developed by the developing roller 25 mounted on the apparatus main body 100.

On the upper side of the apparatus main body 100, a drum cartridge upper guide portion 103 (103a, 103b, 103c, 103d), which is a third main body guide portion, is provided. A drum cartridge lower guide portion 102 (102a, 102b, 102c, 102d), which is a fourth main body guide portion, is provided on the lower side of the apparatus main body 100. The upper guide portion 103 of the drum cartridge and the lower guide portion 102 of the drum cartridge extend along the insertion direction F of the drum cartridge 9, respectively.

Further, on the upper side of the apparatus main body 100, a developing cartridge upper guide portion 105 (105a, 105b, 105c, 105d), which is a first main body guide portion, is provided. A development cartridge lower guide portion 104 (104a, 104b, 104c, 104d), which is a second main body guide portion, is provided on the lower side of the apparatus main body 100. The developing cartridge upper guide portion 105 and the developing cartridge lower guide portion 104 extend along the insertion direction F of the developing cartridge 4, respectively.

When the drum cartridge 9 is inserted, the drum cartridge 9 is placed on the front side of the drum cartridge lower guide portion 102 and the drum cartridge upper guide portion 103 in the mounting direction. Then, the drum cartridge 9 is inserted into the apparatus main body 100 by moving the drum cartridge 9 in the direction of the insertion direction F along the drum cartridge upper guide portion 103 and the drum cartridge lower guide portion 102.

The case of inserting the developing cartridge 4 is the same as that of the drum cartridge 9. The developing cartridge 4 is placed on the front side of the developing cartridge upper guide portion 105 and the developing cartridge lower guide portion 104 in the mounting direction. Then, the developing cartridge 4 is inserted into the apparatus main body 100 by moving the developing cartridge 4 in the direction of the insertion direction F along the developing cartridge upper guide portion 105 and the developing cartridge lower guide portion 104.

(Details of developing cartridge configuration)
Next, the details of the configuration of the developing cartridge 4 according to the first embodiment of the present invention will be described with reference to FIGS. 1, 7, 8 and 9.

As shown in FIG. 7, in this embodiment, an end support member 38 that rotatably supports one end of the developing unit 39 in the axial direction of the developing roller 25 is provided. On the other hand, the other end support that rotatably supports the other end of the developing unit 39 in the axial direction of the developing roller 25 (the end opposite to the end on which the end support member 38 is provided). A member 37 is provided. That is, the end support member 38 and the other end support member 37 are provided on both ends of the development unit 39 with the development unit 39 interposed therebetween.

The other end support member 37 rotatably supports the developing unit 39, and the first rotation center 37a (1st rotation center 37a) as a positioning hole for restricting the position of the developing unit 39 in the direction intersecting the axis of the developing roller 25. (Corresponding to the second hole) is provided. Further, the end support member 38 is provided with a second support hole that rotatably supports the developing unit 39 and movably supports the developing unit 39 in a direction intersecting the axis of the developing roller 25 (preferably in a direction orthogonal to the axis). A moving center 38a (corresponding to the first hole) is provided.

Further, the developing unit 39 is provided with a boss 13a (corresponding to the first shaft) as a support shaft rotatably supported in the first hole 38a. On the other hand, on the other end side of the developing roller 25 in the axial direction with respect to the boss 13a of the developing unit 39, the boss 12a (on the second shaft) as a positioning shaft rotatably supported by the second hole 37a. (Equivalent) is provided. The boss 12a and the boss 13a have a cylindrical shape. In this embodiment, the bosses 12a and 13a are concentric and are provided parallel to the axis of the developing roller 25.

As shown in FIG. 7, the first hole 38a and the boss 13a are engaged, and the second hole 37a and the boss 12a are engaged. Then, the end support member 38 and the other end support member 37 rotate with respect to the developing unit 39 centering on the boss 13a and the boss 12a rotatably supported by the first hole 38a and the second hole 37a. It is possible to move. Further, the end support member 38 and the other end support member 37 are independently movable (rotatable) with respect to the developing unit 39. That is, the end support member 38 supports the end on one end side of the developing roller 25 of the developing unit 39 in the axial direction, and supports the end on the other end side of the developing roller 25 of the developing unit 39 in the axial direction. It is configured not to. On the contrary, the other end support member 37 supports the end portion of the developing unit 39 on the other end side in the axial direction of the developing roller 25, and supports the end portion of the developing unit 39 on the one end side in the axial direction. It is configured not to. That is, the other end support member 37 is rotatable with respect to the developing unit 39 and the end support member 38. The end support member 38 is rotatable with respect to the developing unit 39 and the other end support member 37. In other words, when the other end support member 37 rotates with respect to the developing unit 39, the end support member 38 can be stopped with respect to the developing unit 39 and the other end support member 37. Further, when the end support member 38 rotates with respect to the developing unit 39, the other end support member 37 can be stopped with respect to the developing unit 39 and the end support member 38.

Here, the second hole 37a has a round hole shape. That is, the boss 12a is a positioning portion that is rotatably supported by the second hole 37a and whose movement in the direction intersecting the axis of the developing roller 25 is restricted.

On the other hand, as shown in FIG. 8, the first hole 38a is formed as an elongated hole so as to rotatably support the boss 13a and to move the boss 13a in a direction intersecting the axis of the developing roller 25. To. That is, the first hole 38a is a first regulation portion 38a1 that regulates the radial direction of the boss 13a and a second regulation portion that intersects the first regulation portion, and is more than the first regulation portion 38a1. It is an elongated hole having a large second regulating portion 38a2. By making the first hole 38a a long hole in this way, it is possible to absorb the influence when the axis of the developing roller 25 and the center of the boss 13a and the boss 12a are deviated due to a dimensional tolerance or the like. In this embodiment, the first hole 38a has an oblong hole shape, but the hole shape is not limited to the oblong hole, and may be a rectangular hole or the like.

The first hole 38a and the second hole 37a will be further described with reference to FIG. FIG. 15 is a view of the state in which the first hole 38a and the boss 13a and the second hole 37a and the boss 12a are engaged with each other as viewed from the axial direction of the developing roller 25. The direction in which the movement of the boss 13a is restricted by the first restricting portion 38a1 of the first hole 38a in the direction intersecting (preferably orthogonal to) the axis of the developing roller 25 is defined as the first direction V1. The direction that intersects (preferably orthogonally) the axis of the developing roller 25 and is orthogonal to the first direction V1 (the direction toward the second restricting portion 38a2) is defined as the second direction V2. At this time, the first hole 38a, which is a long hole, allows the boss 13a to move in the second direction V2. On the other hand, the second hole 37a, which is a round hole, restricts the movement of the boss 12a toward the first direction V1 and the second direction V2 described above. At this time, at least in the second direction V2, the distance D2 at which the boss 13a can move in the first hole 38a is longer than the distance at which the boss 12a can move in the second hole 37a.

The first hole 38a will be further described with reference to FIG. FIG. 16 is a diagram illustrating the configuration of the first hole 38a in this embodiment. FIG. 16 shows the developing cartridge 4 when viewed from the axial direction of the developing roller 25 in a state where the developing cartridge 4 is mounted on the image forming apparatus.

As shown in FIG. 16A, the direction in which the first hole 38a of the present embodiment allows the movement of the boss 13a (the direction in which the boss 13a can move in the first hole 38a). Let it be L1. Further, a circle having the same center as the center of the photosensitive drum 1 and passing through the center of the first hole 38a is defined as L2. Then, the line connecting the center of the photosensitive drum 1 and the center of the first hole 38a is defined as L3. At this time, L1 intersects with L2. Further, L1 is inclined with respect to L3. The direction of L1 is not limited to the direction shown in FIG. 16A. For example, as shown in FIG. 16B, it can be configured so that L1 is in the horizontal direction when mounted on the image forming apparatus.

As described above, the first hole 38a and the boss 13a are engaged, and the second hole 37a and the boss 12a are engaged. The first hole 38a allows the boss 13a to move in a direction intersecting the axial direction of the developing roller 25. As a result, the developing unit 39 is rotatably supported by the end support member 38 and is allowed to move in a direction intersecting the axial direction of the developing roller 25. The second hole 37a restricts the boss 12a from moving in a direction intersecting the axial direction of the developing roller 25. As a result, the developing unit 39 is rotatably supported by the other end support member 37, and is restricted from moving in a direction intersecting the axial direction of the developing roller 25. Then, the developing unit 39 rotates about the boss 12a and the boss 13a with respect to the end support member 38 and the other end support member 37.

Next, as shown in FIG. 9, the other end support member 37 is provided with a third engaged portion 37b and a fourth engaged portion 37c. The third engaged portion 37b and the fourth engaged portion 37c are the third main body engaging portion 98a and the fourth main body engaging portion provided in the apparatus main body 100 after the insertion into the apparatus main body 100 is completed. Engage with 98b. As a result, the other end support member 37 is positioned on the device main body 100. Further, the other end support member 37 is provided with a third guided portion 37d and a fourth guided portion 37e, which are guided by the developing cartridge upper guide portion 105 and the developing cartridge lower guide portion 104 at the time of mounting. (See Fig. 7).

Further, the end support member 38 is provided with a first engaged portion 38b and a second engaged portion 38c. The first engaged portion 38b and the second engaged portion 38c are the first main body engaging portion 99a and the second main body engaging portion provided in the apparatus main body 100 after the insertion into the apparatus main body 100 is completed. Engage with 104e. As a result, the end support member 38 is positioned on the device main body 100.

In this embodiment, the second main body engaging portion 104e and the developing cartridge lower guide portion 104 are common. Further, the first engaged portion 38b and the second engaged portion 38c are the first guided portion and the second guided portion guided by the developing cartridge upper guide portion 105 and the developing cartridge lower guide portion 104. It also functions as a department.

Here, in a state where the end support member 38 and the other end support member 37 are positioned on the image forming apparatus, the second hole 37a and the first hole 38a overlap in a direction intersecting the axis of the developing roller 25. It is provided as follows. That is, when viewed from the axial direction of the developing roller 25, the first hole 38a and the second hole 37a are arranged so as to overlap each other. In this embodiment, the center of the first hole 38a coincides with the center of the second hole 37a (see FIG. 8). On the other hand, as described above, in this embodiment, the boss 12a and the boss 13a are concentric and are provided parallel to the axis of the developing roller 25. That is, when the end support member 38 and the other end support member 37 are positioned on the image forming apparatus and the boss 13a is located at the center of the first hole 38a, the axis of the developing roller 25 is aligned with the photosensitive drum 1. It will be in a state parallel to the axis of.

As shown in FIG. 1, the bosses 12a and 13a both form the rotation center of the developing unit 39 in a state where the other end support member 37 and the end support member 38 are respectively positioned on the apparatus main body 100. The developing unit 39 rotates around the bosses 12a and 13a, so that the developing roller 25 comes into contact with the photosensitive drum 1. In this embodiment, the boss 12a and the boss 13a, and the second hole 37a and the first hole 38a generate a moment in the direction in which the developing roller 25 abuts on the photosensitive drum 1 due to the weight of the developing unit 39. It is provided at the position where it is used.

As described above, at the time of image formation, the developing roller 25 of the developing cartridge 4 comes into contact with the photosensitive drum 1 to perform a visible image. In this embodiment, the urging portion 31e (corresponding to the force receiving portion) of the developing frame 31 is formed by the unit urging member 80 (corresponding to the force applying portion) of the apparatus main body 100 (see FIG. 2). The developing unit is urged in the urging direction A. Then, the developing roller 25 comes into contact with the photosensitive drum 1. That is, the urged portion 31e is provided so that the developing roller 25 moves in the direction of contacting the photosensitive drum 1 when urged by the unit urging member 80.

Here, the structure of the unit urging member 80 is shown in FIG. FIG. 17 is a view of the developing cartridge 4 viewed from the axial direction of the developing roller 25. The developing unit 39 is located on the back side of the paper surface, and the end support member 38 is located on the front side of the paper surface. The urging portion 31e of the developing frame 31 is urged by the unit urging member 80 in the developing unit urging direction A1 direction (same as the above-mentioned A direction). Then, the developing unit 39 rotates in the R1 direction. Then, the developing roller 25 comes into contact with the photosensitive drum 1. Further, the urged portion 31e of the developing frame 31 is urged by the unit urging member 80 to A2 in the direction opposite to the developing unit urging direction A1. Then, the developing unit rotates in the R2 direction. Then, the developing roller 25 separates from the photosensitive drum 1.

In this embodiment, the applied portion 31e is arranged so that the distance from the center of the developing roller 25 to the applied portion 31e is longer than the distance from the center of the developing roller 25 to the center of the boss 13a. ing. Further, in the present embodiment, when the straight line Q1 connecting the center of the developing roller 25 and the center of the boss 13a and the straight line Q2 orthogonal to the straight line Q1 are drawn so as to pass through the center of the boss 13a, the applied portion 31e is subjected to. It is arranged in the area opposite to the developing roller 25 with the straight line Q2 as a boundary.

When the urging portion 31e is urged in the urging direction A of the developing unit, the developing roller 25 tries to come into contact with the photosensitive drum 1. At this time, the boss 13a moves in the first hole 38a, which is a long hole, toward the second regulating portion 38a2 in a direction away from the photosensitive drum 1. On the other hand, the boss 12a on the opposite side is restricted from moving in the direction intersecting the axis of the developing roller 25 by the second hole 37a which is a round hole. Therefore, the boss 12a cannot move beyond the slight gap between the boss 12a and the second hole 37a. As a result, the developing cartridge 4 is in a state where the axis of the developing roller 25 is deviated from the axis of the photosensitive drum 1, that is, a state in which the alignment of the developing unit 39 is misaligned. Further, the same state can be obtained by moving the position of the center of gravity of the developing unit 39 from G1 to G2 by consuming the toner in the developing unit 39. Here, FIG. 18 is a schematic diagram illustrating the above-mentioned alignment deviation. FIG. 18A shows a state in which the axis of the developing roller 25 and the axis of the photosensitive drum 1 are substantially parallel to each other. FIG. 18B shows a state in which the axis of the developing roller 25 and the axis of the photosensitive drum 1 are not parallel, that is, a state in which an alignment deviation occurs. As shown in FIG. 18, the boss 13a is allowed to move away from the photosensitive drum 1 by the first hole 38a which is an elongated hole. On the other hand, the boss 12a is restricted from moving in the direction intersecting the axis of the developing roller 25 by the second hole 37a which is a round hole. Therefore, the axis of the developing roller 25 may not be parallel to the axis of the photosensitive drum 1 (a state in which an alignment deviation occurs). In a state where this alignment deviation occurs, the developing roller 25 may not be able to come into contact with the photosensitive drum 1.

On the other hand, in the developing cartridge 4 in this embodiment, the end support member 38 is provided with a tension spring 40 which is an elastic member as a shaft urging portion (urging member). Further, the end support member 38 includes a spring fixing boss 38d which is an elastic member support portion that supports the tension spring 40. One end of the tension spring 40 is supported by the spring fixing boss 38d, which is the elastic member support portion of the end support member 38, and the other end is supported by the boss 13a.

The tension spring 40 urges the boss 13a in a direction intersecting (preferably orthogonal to) the axis of the developing roller 25. By doing so, as shown in FIG. 1 (b), the boss 13a is urged in the direction opposite to the urging direction A of the developing unit. That is, the center of the boss 13a is urged in the first hole 38a in a direction approaching the center of the photosensitive drum 1 (a direction in which the distance between the center of the boss 13a and the center of the photosensitive drum 1 becomes shorter). In this embodiment, this direction is the direction in which the center of the boss 13a coincides with the center of the second hole 37a. As a result, the distance between the boss 13a and the center of the photosensitive drum 1 approaches the same distance as the distance between the boss 12a and the center of the photosensitive drum 1. That is, the difference in the distance between the boss 13a and the center of the photosensitive drum 1 and the difference in the distance between the boss 12a and the center of the photosensitive drum 1 are smaller than in the case where the tension spring 40 which is the urging member is not used. Then, the axis of the developing roller 25 approaches parallel to the axis of the photosensitive drum 1. That is, the angle formed by the axis of the developing roller 25 and the axis of the photosensitive drum 1 becomes smaller than in the case where the tension spring 40, which is an urging member, is not used. Therefore, the developing roller 25 can be stably brought into contact with the photosensitive drum 1.

The distance between the boss 13a and the center of the photosensitive drum 1 and the distance between the boss 12a and the center of the photosensitive drum 1 are preferably the same, but they do not have to be exactly the same. Further, it is desirable that the axis of the developing roller 25 and the axis of the photosensitive drum 1 are parallel, but it is not necessary to be completely parallel.

Here, FIG. 19 is a diagram illustrating the arrangement of the tension spring 40 as the urging member. FIG. 19 is a view of the developing cartridge 4 viewed from the axial direction of the developing roller 25, as in FIG. The developing unit 39 is located on the back side of the paper surface, and the end support member 38 is located on the front side of the paper surface. For example, as shown in FIG. 19, a protruding portion 13c1 or a protruding portion 13c2 may be provided as a part of the developing unit 39. Then, the tension spring 40 may be arranged between the spring fixing boss 38d and the protrusion 13c1. Further, the tension spring 40 may be arranged between the spring fixing boss 38d and the protrusion 13c2. Even with this configuration, the boss 13a can be urged in a direction intersecting the axis of the developing roller 25 (preferably in an orthogonal direction). Then, the boss 13a can be brought closer to the center of the photosensitive drum 1 in the direction intersecting the axis of the developing roller 25 (preferably in the orthogonal direction). Therefore, the developing roller 25 can be stably brought into contact with the photosensitive drum 1.

On the other hand, in the configuration in which the tension spring 40 directly urges the boss 13a, the tension spring 40 hardly generates a force (moment) for rotating the developing unit 39. Therefore, when the developing roller 25 is brought into contact with the photosensitive drum 1, the load applied to the unit urging member 80 is unlikely to increase. For example, when the tension spring 40 is applied to the protrusion 13c2, a force is applied in the opposite direction to the movement of the developing roller 25 to abut on the photosensitive drum 1. Further, when a tension spring is applied to the protruding portion 13c1, a force is applied in the opposite direction to the movement of separating the developing roller 25 from the photosensitive drum 1. Therefore, by directly urging the boss 13a, the load applied to the unit urging member 80 is unlikely to increase.

Further, it is assumed that the tension spring 40 is applied to the protrusion 13c1 and the developing unit 39 rotates in the R1 direction in the drawing so that the developing roller 25 comes into contact with the photosensitive drum 1. Then, the protruding portion 13c1 also rotates in the R1 direction in the figure. On the other hand, the spring fixing boss 38d is provided on the end support member 38. As described above, the end support member 38 is fixed to the image forming apparatus. Therefore, when the developing unit 39 rotates in the R1 direction in the drawing, the distance between the protruding portion 13c1 and the spring fixing boss 38d becomes short. As a result, the force with which the tension spring 40 pulls the protrusion 13c1 decreases. Therefore, it is necessary to increase the force of the tension spring 40.

On the other hand, in the configuration in which the boss 13a is directly urged, the distance between the boss 13a and the spring fixing boss 38d does not change even when the developing unit 39 rotates. Therefore, the force with which the tension spring 40 pulls the boss 13a is unlikely to decrease.

That is, the tension spring 40 may be any one that urges the developing unit 39, but it is desirable to urge the boss 13a.

In summary, in this embodiment, the tension spring 40 is provided on the end support member 38 of the developing unit 39 or the end support member 38. The tension spring 40 is an urging member that urges the developing unit 39 among the developing unit 39 or the end support member 38 in a direction intersecting the axial direction of the developing roller 25.

In this embodiment, the end support member 38 and the other end support member 37 are provided at both ends of the developing unit 39, but the present invention is not limited to this configuration. For example, as shown in FIG. 10, the other end support member 37 may be omitted. That is, the developing unit 39 is rotatably supported on the other end of the developing roller 25 of the developing unit 39 in the axial direction (the end opposite to the end on which the end supporting member 38 is provided). A support portion 137 on the device side is provided. The device-side support portion 137 is fixedly provided on the back side of the device main body 100. Then, the boss 12a may be used as a supported portion (positioning shaft), and the device-side support portion 137 may be provided with a hole 137a (positioning hole) corresponding to the second hole 37a in the present embodiment. At this time, the boss 12a is a positioning portion that is rotatably supported by the hole 137a and whose movement in the direction intersecting the axis of the developing roller 25 is restricted.

In this case, the boss 12a is removable from the hole 137a, and the developing cartridge 4 is rotatably supported by the hole 137a via the boss 12a. Since the end support member 38 is independent of the device-side support portion 137, it is rotatable with respect to the developing cartridge 4 independently of the device-side support portion 137. Since the function of the device-side support portion 137 is the same as that of the other end support member 37 in the state of being mounted on the device main body 100, the description thereof is omitted here.

The device-side support portion 137 may be configured to extend the wall surface on the back side of the drum cartridge 9 and fix it to a part thereof.

Further, in the present embodiment, as the positioning portion of the developing unit 39, the other end support member 37 is provided with the second hole 37a, and the developing unit 39 is provided with the boss 12a, but the present invention is not limited to this configuration. That is, the hole corresponding to the second hole 37a (positioning hole) in this embodiment may be provided in either the developing unit 39 or the other end support member 37. In that case, the positioning shaft corresponding to the boss 12a in this embodiment may be arranged on the other side of the developing unit 39 or the other end support member 37. Further, in the form in which the other end support member 37 is omitted, a positioning shaft corresponding to the boss 12a is provided on either the developing unit 39 or the device-side support portion, and the other of the developing unit 39 or the device-side support portion has a position. A hole corresponding to the second hole 37a may be provided.

[Example 2]
Next, the configuration of the developing cartridge 4 according to the second embodiment of the present invention will be described with reference to FIGS. 11, 12, and 13. In this embodiment, the components different from those of the first embodiment will be particularly described, and the description of the same components as those of the first embodiment will be omitted in principle.

As shown in FIG. 12, an end support member 48 (corresponding to the end support member 38 of the first embodiment) is provided on one end side of the developing roller 25 of the developing unit 39 in the axial direction. The end support member 48 is provided with a first hole 48a that engages with the boss 13a provided in the developing unit 39. The first hole 48a is the same as the first hole 38a of the first embodiment, and rotatably supports the boss 13a. Further, the end support member 48 is provided with a first engaged portion 48b and a second engaged portion 48c. Similar to that shown in the first embodiment, the first engaged portion 48b and the second engaged portion 48c are provided in the apparatus main body 100 after the development cartridge 4 has been inserted into the apparatus main body 100. It engages with the main body engaging portion 99a and the second main body engaging portion 104e (see FIG. 13).

In this embodiment, as the shaft urging portion (urging member) for urging the boss 13a, the pressing lever 41 (lever member) as the pressing member and the pressing urging portion for urging the pressing lever 41 toward the boss 13a. A tension spring 140 (lever urging member) is used as the member.

As shown in FIG. 11, the end support member 48 is provided with a pressing lever 41. The pressing lever 41 is formed with a lever supported portion 41b as a pressed supported portion and a spring fixing portion 41a as a urging member locking portion at a position facing the lever supported portion 41b. Further, the end support member 48 has a lever support boss 48e as a pressing support portion and a spring fixing boss 48d as a urging member locked portion. The lever support boss 48e is provided so that the pressing lever 41 is located on the opposite side of the center of the first hole 48a with respect to the direction in which the boss 13a is moved. The lever supported portion 41b is rotatably supported by the lever support boss 48e. One end of the tension spring 140 is supported by the spring fixing portion 41a, and the other end is supported by the spring fixing boss 48d. Further, the pressing lever 41 urges the boss 13a between the lever supported portion 41b, which is a position supported by the end support member 48, and the spring fixing portion 41a, which is a position urged by the tension spring 140. It is configured to do.

Similar to the tension spring 40 described in the first embodiment, in order to reduce the influence of the misalignment of the developing roller 25, the direction (preferably orthogonal to) the boss 13a intersecting the axis of the developing roller 25 with this pressing lever 41. To be urged to. In this embodiment, the distance from the lever supported portion 41b of the pressing lever 41 to the spring fixing portion 41a is longer than the distance to the position where the boss 13a is urged. Therefore, the spring pressure of the tension spring 140 for obtaining the force required to urge the boss 13a can be reduced. Then, the developing roller 25 can be stably brought into contact with the photosensitive drum 1.

That is, as shown in FIG. 11B, the boss 13a is urged in the direction opposite to the developing unit urging direction A. That is, in the direction intersecting the axial direction of the developing roller 25, the center of the boss 13a approaches the center of the photosensitive drum 1 in the first hole 48a (the center of the boss 13a and the center of the photosensitive drum 1). It is urged in the direction that the distance becomes shorter). In this embodiment, this direction coincides with the center of the second hole 37a. As a result, the distance between the boss 13a and the center of the photosensitive drum 1 approaches the same distance as the distance between the boss 12a and the center of the photosensitive drum 1. That is, the difference in the distance between the boss 13a and the center of the photosensitive drum 1 and the difference in the distance between the boss 12a and the center of the photosensitive drum 1 are smaller than in the case where the pressing lever 41 which is an urging member is not used. Then, the axis of the developing roller 25 approaches parallel to the axis of the photosensitive drum 1. That is, the angle formed by the axis of the developing roller 25 and the axis of the photosensitive drum 1 becomes smaller than in the case where the pressing lever 41, which is an urging member, is not used. Therefore, the developing roller 25 can be stably brought into contact with the photosensitive drum 1.

The distance between the boss 13a and the center of the photosensitive drum 1 and the distance between the boss 12a and the center of the photosensitive drum 1 are preferably the same, but they do not have to be exactly the same. Further, it is desirable that the axis of the developing roller 25 and the axis of the photosensitive drum 1 are parallel, but it is not necessary to be completely parallel.

Further, as in the first embodiment, the pressing lever 41 may urge the developing unit 39, but it is desirable to urge the boss 13a.

In summary, in this embodiment, the pressing lever 41 and the tension spring 140 are provided on the end support member 48 of the developing unit 39 or the end support member 48. The pressing lever 41 and the tension spring 140 are urging members for urging the developing unit 39 among the developing unit 39 or the end support member 48 in a direction intersecting the axial direction of the developing roller 25.

The method of assembling the developing cartridge 4 described in this embodiment will be described with reference to FIG.

First, the developing unit 39 is assembled by filling the developing frame 31 with toner and assembling the toner supply roller 34 and the developing roller 25 (first step).

Next, the pressing lever 41 is attached to the lever support boss 48e in advance, and the end support member 48 in a state where the tension spring 140 is attached to the spring fixing portion 41a and the spring fixing boss 48d is subjected to the first step. Attached to the developing unit 39 (second step).

In this way, the developing cartridge 4 is assembled. When the other end support member 37 is used, it may be attached to the developing unit 39 by another step.

According to this assembling method, it is not necessary to assemble the tension spring 140 after assembling the end support member 48 to the developing unit 39, so that the assembling property of the developing cartridge 4 can be improved.

[Example 3]
Next, the configuration of the developing cartridge 4 according to the third embodiment of the present invention will be described. In addition, in this Example, the components different from those of Examples 1 and 2 will be particularly described, and the description of the same components as those of Examples 1 and 2 will be omitted in principle.

In Examples 1 and 2, the developing unit 39 includes the boss 13a. The first holes 38a and 48a were provided in the end support members 38 and 48. However, the first shaft (corresponding to the boss 13a) as the support shaft may be provided on either the developing unit or the end support member. Further, the first hole that engages with the first shaft as the support shaft may be provided on either the developing unit or the end support member, whichever is the other.

Further, as shown in another embodiment, the boss 12a may be provided on either the developing unit 39 or the other end support member 37. The second hole 37a that engages with the boss 12a may be provided on either the developing unit 39 or the other end support member 37, whichever is the other.

The configuration of this embodiment will be described with reference to FIG. FIG. 20 is a schematic cross-sectional view showing the configuration of the developing cartridge 4 of this embodiment. FIG. 20 is a cross-sectional view of the developing cartridge 4 as viewed from a direction orthogonal to the axis of the developing roller 25.

As shown in FIG. 20, in this embodiment, the boss 138a (corresponding to the bosses 13a of Examples 1 and 2) as the support shaft (first shaft) is the end support member 138 (Examples 1 and 2). (Corresponding to the end support members 38, 48). Further, the developing unit 139 is provided with a first hole 139a (corresponding to the first hole 38a of Examples 1 and 2) as a support hole. Further, as shown in another embodiment, the boss 12a is provided on either the developing unit 139 or the other end support member 37. The second hole 37a that engages with the boss 12a is provided on either the developing unit 139 or the other end support member 37, whichever is the other.

As in the other embodiments, the first hole 139a and the boss 138a are engaged, and the second hole 37a and the boss 12a are engaged. As will be described later, the first hole 139a is allowed to move with respect to the boss 138a in a direction intersecting the axial direction of the developing roller 25. As a result, the developing unit 139 is rotatably supported by the end support member 138 and is allowed to move in a direction intersecting the axial direction of the developing roller 25. The second hole 37a restricts the boss 12a from moving in a direction intersecting the axial direction of the developing roller 25. As a result, the developing unit 139 is rotatably supported by the other end support member 37, and is restricted from moving in a direction intersecting the axial direction of the developing roller 25. Then, similarly to the first embodiment, the developing unit 139 rotates around the boss 12a and the boss 138a, and the line connecting the boss 12a and the boss 138a as the rotation center. Then, the developing roller 25 can come into contact with and separate from the photosensitive drum 1.

FIG. 21 is a view of the developing cartridge 4 in this embodiment as viewed from the axial direction of the developing roller 25.

Similar to the first embodiment, the end support member 138 and the other end support member 37 can rotate independently of the developing unit 139. Further, in a state where the developing cartridge 4 is mounted on the image forming apparatus, the end support member 138 and the other end supporting member 37 are positioned on the image forming apparatus. Further, the photosensitive drum 1 is also positioned on the image forming apparatus via the drum cartridge 9. The urging portion 31e of the developing frame 31 is urged in the developing unit urging direction A1 by the unit urging member 80 of the apparatus main body 100. Then, the developing unit 139 rotates in the direction of the arrow R1, and the developing roller 25 comes into contact with the photosensitive drum 1. As in the other embodiments, when the urged portion 31e is urged in the developing unit urging direction A2, the developing roller 25 is separated from the photosensitive drum 1.

Similar to the first embodiment, when the straight line Q1 connecting the center of the developing roller 25 and the center of the boss 138a and the straight line Q2 orthogonal to the straight line Q1 are drawn so as to pass through the center of the boss 138a, the applied portion 31e becomes It is arranged in the area opposite to the developing roller 25 with the straight line Q2 as a boundary.

When the urged portion 31e is urged in the developing unit urging direction A1, the developing unit 139 rotates and the developing roller 25 tries to come into contact with the photosensitive drum 1. At this time, in the direction intersecting the axis of the developing roller 25, the first hole 139a, which is a long hole, moves in a direction away from the photosensitive drum 1. On the other hand, since the boss 138a is provided on the end support member 138, the position with respect to the photosensitive drum 1 does not change.

On the other hand, the boss 12a on the opposite side and the second hole 37a, which is a round hole, are restricted from moving in the direction intersecting the axis of the developing roller 25. As a result, similarly to the first embodiment, the developing cartridge 4 is in a state where the axis of the developing roller 25 is slanted with respect to the axis of the photosensitive drum 1, that is, a state in which the alignment of the developing unit 139 is misaligned. Here, FIG. 22 is a schematic diagram illustrating the above-mentioned alignment misalignment, as in FIG. 18 in the first embodiment. FIG. 22A shows a state in which the axis of the developing roller 25 and the axis of the photosensitive drum 1 are substantially parallel to each other. FIG. 22B shows a state in which the axis of the developing roller 25 and the axis of the photosensitive drum 1 are not parallel, that is, a state in which an alignment deviation occurs. As shown in FIG. 22, the first hole 139a, which is a long hole, moves away from the optical drum 1 while engaging with the boss 138a. On the other hand, the movement of the boss 12a and the second hole 37a, which is a round hole, in the direction intersecting the axis of the developing roller 25 is restricted. Therefore, the axis of the developing roller 25 is not parallel to the axis of the photosensitive drum 1. In a state where this alignment deviation occurs, the developing roller 25 may not be able to come into contact with the photosensitive drum 1.

Therefore, as shown in FIG. 23A, the developing cartridge 4 includes a tension spring 240, which is an elastic member as an urging member, in the developing unit 139. Further, the developing unit 139 includes a spring fixing boss 239d which is an elastic member supporting portion for supporting the tension spring 240. One end of the tension spring 240 is supported by the spring fixing boss 239d, which is the elastic member support portion of the developing unit 139, and the other end is supported by the boss 138a of the end support member 138.

The tension spring 240 urges the boss 138a in a direction intersecting (preferably orthogonal to) the axis of the developing roller 25. That is, as shown in FIG. 23A, the boss 138a is urged by the tension spring 240 so that the first hole 139a moves in the direction opposite to the developing unit urging direction A1.

In the direction intersecting the axial direction of the developing roller 25, the tension spring 240 urges the boss 138a so that the center of the first hole 139a moves in the direction opposite to the developing unit urging direction A1. Then, the center of the first hole 139a moves in a direction approaching the center of the photosensitive drum 1 (a direction in which the distance between the center of the first hole 139a and the center of the photosensitive drum 1 becomes shorter). In this embodiment, this direction is such that the center of the first hole 139a coincides with the center of the second hole 37a or the boss 12a. As a result, the distance between the first hole 139a and the center of the photosensitive drum 1 approaches the same distance as the distance between the second hole 37a or the boss 12a and the center of the photosensitive drum 1. That is, the distance between the first hole 139a and the center of the photosensitive drum 1 is up to the center of the second hole 37a or the boss 12a and the photosensitive drum 1 as compared with the case where the tension spring 240 which is an urging member is not used. The difference in distance between them becomes smaller. Then, the axis of the developing roller 25 approaches so as to be parallel to the axis of the photosensitive drum 1. That is, the angle formed by the axis of the developing roller 25 and the axis of the photosensitive drum 1 becomes smaller than in the case where the tension spring 240, which is an urging member, is not used. Therefore, the developing roller 25 can be stably brought into contact with the photosensitive drum 1.

The distance between the first hole 139a and the center of the photosensitive drum 1 and the distance between the second hole 37a or the boss 12a and the center of the photosensitive drum 1 are preferably the same, but must be exactly the same. There is no. Further, it is desirable that the axis of the developing roller 25 is parallel to the axis of the photosensitive drum 1, but it is not necessary to be completely parallel.

Further, as in the first embodiment, the tension spring 240 may urge the end support member 138, but it is desirable to urge the boss 138a. In the above configuration, the tension spring 240 is provided in the developing unit 139 of the developing unit 139 or the end support member 138. The tension spring 240 is an urging member that urges the end support member 138 of the developing unit 139 or the end support member 138 in a direction intersecting the axial direction of the developing roller 25.

Further, as another configuration, as shown in FIG. 23 (b), instead of the tension spring 240 described above, a pressing lever as a urging member as described in the second embodiment and a lever urging member are used. You can also.

In this configuration, as the urging member for urging the boss 138a, a pressing lever 241 and a tension spring 340 for urging the pressing lever 241 toward the boss 138a are used.

The developing unit 139 is provided with a pressing lever 241. The pressing lever 241 has a lever supported portion 241b as a pressed supported portion and a spring fixing portion 241a as a urging member locking portion at a position facing the lever supported portion 241b. Further, the developing unit 139 has a lever support boss 139e as a pressing support portion and a spring fixing boss 139d as a urging member locked portion. The lever support boss 139e is provided so that the pressing lever 241 presses the boss 138a and is located on the opposite side of the center of the boss 138a with respect to the direction in which the developing unit 139 moves. The lever supported portion 241b is rotatably supported by the lever support boss 139e. One end of the tension spring 340 is supported by the spring fixing portion 241a, and the other end is supported by the spring fixing boss 139d. Further, the pressing lever 241 urges the boss 138a between the lever supported portion 241b, which is a position supported by the developing unit 139, and the spring fixing portion 241a, which is a position urged by the tension spring 340. It is composed of.

Similar to the tension spring 240, in order to reduce the influence of the misalignment of the developing roller 25, the pressing lever 241 urges the boss 138a in the direction intersecting the axis of the developing roller 25 (preferably in the direction orthogonal to the axis).

In the direction intersecting the axial direction of the developing roller 25, the pressing lever 241 and the tension spring 340 urge the boss 138a so that the center of the first hole 139a moves in the direction opposite to the developing unit urging direction A1. .. In the direction intersecting the axial direction of the developing roller 25 by the pressing lever 241 and the tension spring 340, the center of the first hole 139a approaches the center of the photosensitive drum 1 (the center of the first hole 139a and the photosensitive drum). Move in the direction in which the distance of the center of 1 becomes shorter). In this embodiment, this direction is such that the center of the first hole 139a coincides with the center of the second hole 37a or the boss 12a. As a result, the distance between the first hole 139a and the center of the photosensitive drum 1 approaches the same distance as the distance between the second hole 37a or the boss 12a and the center of the photosensitive drum 1. That is, the distance between the first hole 139a and the center of the photosensitive drum 1 is up to the center of the second hole 37a or the boss 12a and the photosensitive drum 1 as compared with the case where the pressing lever 241 which is an urging member is not used. The difference in distance between them becomes smaller. Then, the axis of the developing roller 25 approaches so as to be parallel to the axis of the photosensitive drum 1. That is, the angle formed by the axis of the developing roller 25 and the axis of the photosensitive drum 1 is smaller than that in the case where the pressing lever 241 is not used. Therefore, the developing roller 25 can be stably brought into contact with the photosensitive drum 1.

The distance between the first hole 139a and the center of the photosensitive drum 1 and the distance between the second hole 37a or the boss 12a and the center of the photosensitive drum 1 are preferably the same, but must be exactly the same. There is no. Further, it is desirable that the axis of the developing roller 25 is parallel to the axis of the photosensitive drum 1, but it is not necessary to be completely parallel.

Further, as in the second embodiment, the pressing lever 241 may urge the end support member 138, but it is desirable to urge the boss 138a. In the above-described configuration, the pressing lever 241 and the tension spring 340 are provided in the developing unit 139 of the developing unit 139 or the end support member 138. The pressing lever 241 and the tension spring 340 are urging members that urge the end support member 138 of the developing unit 139 or the end support member 138 in the direction intersecting the axial direction of the developing roller 25.

As described above, according to the present invention, it is possible to improve the stability of contact of the developing roller as the developer carrier with respect to the photosensitive drum as the image carrier.

A Development unit urging direction B Development roller rotation direction F Insertion direction G1 Center of gravity position when toner consumption is low G2 Center of gravity position when toner consumption is low Q1 Straight line connecting the center of the developing roller 25 and the boss 13a Q2 Development roller 25 1 (1a to 1d) Photosensitive drum 4 (4a to 4d) Development cartridge 9 Drum cartridge 12 Development back bearing 12a Boss 13 Pre-development bearing 13a Boss 25 (25a to 25d) ) Developing roller 31 Developing frame 31a Developer accommodating chamber 31b Opening 31f Developing chamber 31d Partition 31e Impressed portion (force receiving portion)
37 Support member at the other end 37a First rotation center (second hole)
37b Third engaged part 37c Fourth engaged part 38, 48 End support members 38a, 48a Second rotation center (first hole)
38a1, 48a1 First regulation part 38a2, 48a2 Second regulation part 38b, 48b First engagement part 38c, 48c Second engagement part 38d, 48d Spring fixing boss 38e, 48e Lever support boss 39 Development Unit 40 Tension spring 41 Pressing lever 41a Spring fixing part 41b Lever supported part 80 (80a, 80b, 80c, 80d) Unit urging member (force applying part)
100 Device body 101 (101a, 101b, 101c, 101d) Mounting port 102 (102a, 102b, 102c, 102d) Drum cartridge lower guide section 103 (103a, 103b, 103c, 103d) Drum cartridge upper guide section 104 (104a, 104b) , 104c, 104d) Development cartridge lower guide part 105 (105a, 105b, 105c, 105d) Development cartridge upper guide part 137 Device side support part

Claims (21)

A developing unit including a developer carrier that supplies a developer to an image carrier that supports an electrostatic latent image, and a developing frame that supports the developer carrier.
An end support member that rotatably supports the developing unit on one end side in the axial direction of the developing agent carrier, and an end supporting member.
On the other end side in the axial direction, the other end support member that rotatably supports the developing unit and
The first axis provided in the developing unit and
A second shaft provided on either the developing unit or the other end support member, and
A first hole provided in the end support member that supports the first shaft so that the developing unit rotates about the first shaft and the second shaft. And a first hole configured to allow the first axis to move in a direction intersecting the axis direction.
A second hole provided in either the other of the developing unit or the other end support member so that the developing unit rotates about the first axis and the second axis. A second hole that supports the second axis and is configured to restrict the movement of the second axis in a direction intersecting the axial direction.
An urging member that urges the first axis in a direction intersecting the axis direction,
It is a developing device equipped with
The developing device is configured to be detachably attached to and attached to the image forming device separately from the image carrier.
A developing apparatus characterized in that the end support member and the other end support member can rotate independently of the developing unit. Claimed, wherein the urging member urges the first axis so that the center of the first axis approaches the center of the image carrier in a direction intersecting the axis direction. The developing apparatus according to 1. The developing apparatus according to claim 2, further comprising a force receiving portion provided in the developing unit and urged so that the developing agent carrier moves in a direction of contacting the image carrier. The developing apparatus according to claim 3, wherein when the force receiving portion is urged, the first axis moves in a direction away from the center of the image carrier. The force receiving portion is orthogonal to a straight line connecting the center of the developer carrier and the center of the first axis, and is opposite to the developer carrier with respect to the straight line passing through the center of the first axis. The developing apparatus according to claim 3, wherein the developing apparatus is provided in the area of. The developing apparatus according to claim 5, wherein the force receiving portion is urged by a force applying portion provided in the image forming apparatus. The method according to any one of claims 1 to 6, wherein the urging member is an elastic member having one end supported by the end support member and the other end supported by the first shaft. Developing equipment. The urging member
A lever member rotatably supported by the end support member and
The developing apparatus according to any one of claims 1 to 6, wherein the lever member includes a lever urging member that urges the lever member toward the first axis. 8. The lever member is characterized in that the first shaft is urged between a position urged by the lever urging member and a position supported by the end support member. The developing device described in. The first hole is an elongated hole.
The slotted hole has a first regulating portion that regulates the position of the first shaft in the first direction, and a first regulating portion.
A second regulating unit that regulates the position of the first axis in the second direction intersecting the first direction is provided.
The movable distance of the first axis regulated by the second regulator in the second direction is the movement of the first axis regulated by the first regulator in the first direction. The developing apparatus according to any one of claims 1 to 9, wherein the developing apparatus is longer than a certain distance. The developing device according to any one of claims 1 to 10, wherein the developing device is removable from the image forming device in the axial direction. The developing apparatus according to any one of claims 1 to 11, wherein the developing apparatus is detachable from the image forming apparatus provided with the image carrier to which the developing agent carrier comes into contact. A developing unit including a developer carrier that supplies a developer to an image carrier that supports an electrostatic latent image, and a developing frame that supports the developer carrier.
An end support member that rotatably supports the developing unit on one end side in the axial direction of the developing agent carrier, and an end supporting member.
On the other end side in the axial direction, the other end support member that rotatably supports the developing unit and
The first shaft provided on the end support member and
A second shaft provided on either the developing unit or the other end support member, and
A first hole provided in the developing unit, the developing unit being supported by the first shaft and supported by the first shaft so as to rotate about the first shaft and the second shaft. A first hole configured to allow movement in a direction intersecting the axial direction with respect to the first axis, and a first hole.
A second hole provided in either the other of the developing unit or the other end support member so that the developing unit rotates about the first axis and the second axis. A second hole that supports the second axis and is configured to restrict the movement of the second axis in a direction intersecting the axial direction.
An urging member that urges the first axis in a direction intersecting the axis direction,
It is a developing device equipped with
The developing device is configured to be detachably attached to and attached to the image forming device separately from the image carrier.
The developing unit is provided with a force receiving portion that urges the developer carrier to abut on the image carrier.
A developing apparatus characterized in that when the force receiving portion is urged, the first hole moves in a direction away from the center of the image carrier. Claimed, wherein the urging member urges the first axis so that the center of the first hole approaches the center of the image carrier in a direction intersecting the axis direction. 13. The developing apparatus according to 13. The force receiving portion is orthogonal to a straight line connecting the center of the developer carrier and the center of the first axis, and is opposite to the developer carrier with respect to the straight line passing through the center of the first axis. The developing apparatus according to claim 13, wherein the developing apparatus is provided in the area of. A developing unit including a developer carrier that supplies a developer to an image carrier that supports an electrostatic latent image, and a developing frame that supports the developer carrier.
An end support member that rotatably supports the developing unit on one end side in the axial direction of the developing agent carrier, and an end supporting member.
On the other end side in the axial direction, the other end support member that rotatably supports the developing unit and
A first shaft provided on either the developing unit or the end support member, and
A second shaft provided on either the developing unit or the other end support member, and
A first hole provided in either the other of the developing unit or the end support member so that the developing unit rotates about the first axis and the second axis. A first hole that engages with the first axis and is configured to allow the developing unit to move in a direction intersecting the axis direction.
A second hole provided in either the other of the developing unit or the other end support member so that the developing unit rotates about the first axis and the second axis. A second hole that engages with the second axis and is configured to restrict the developing unit from moving in a direction intersecting the axial direction.
A urging member provided on either one of the developing unit or the end support member and urging the other of the developing unit or the end support member in a direction intersecting the axial direction. ,
The developing apparatus, wherein the end support member and the other end support member can rotate independently of the developing unit. The developing apparatus according to claim 16, wherein the urging member urges the first shaft. The developing apparatus according to claim 16 or 17, further comprising a force receiving portion provided in the developing unit and urged so that the developing agent carrier abuts on the image carrier. The force receiving portion is orthogonal to a straight line connecting the center of the developer carrier and the center of the first axis, and is opposite to the developer carrier with respect to the straight line passing through the center of the first axis. The developing apparatus according to claim 18, wherein the developing apparatus is provided in the area of. The developing apparatus according to any one of claims 16 to 19, wherein the developing apparatus is configured to be detachably attached to and detachable from the image forming apparatus separately from the image carrier. The developing apparatus according to any one of claims 1 to 20 and
With the image carrier
An image forming apparatus characterized in that the image is detachably provided.

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