CN110320781A - Image forming apparatus - Google Patents

Abstract

An image forming apparatus includes: a developing cartridge including a developing roller; a photosensitive drum; a drawer including a frame; a pressing member; and a driving unit. The developing cartridge can be attached to the frame in a state where the outer circumferential surface of the developing roller faces the outer circumferential surface of the photosensitive drum. In response to the movement of a portion of the developing cartridge in the axial direction, the frame moves the developing cartridge in a separation direction in which the outer circumferential surface of the developing roller is separated from the outer circumferential surface of the photosensitive drum. The pressing member is movable in the axial direction between a contact position and a non-contact position separated from the developing cartridge. The pressing member in the contact position is in contact with the developing cartridge, and moves the developing cartridge in the axial direction.

Description

image forming equipment

technical field

The present disclosure relates to an image forming apparatus.

Background technique

Electrophotographic type image forming apparatuses such as laser printers and LED printers are well known in the art. The developing cartridge is used in the image forming apparatus. The developing cartridge includes a developing roller for supplying toner. Conventional image forming apparatuses are described in the related art. The image forming apparatuses described in the related art include a drawer unit. The drawer unit includes a photosensitive drum. The developing cartridge may be attached to the drawer unit. When the developing cartridge is attached to the drawer unit, the developing roller contacts the photosensitive drum.

A developing cartridge disclosed in another related art is attachable to a drum cartridge. The drum cartridge includes a photosensitive drum. When the developing cartridge is attached to the drum cartridge, the developing roller is in contact with the photosensitive drum. Then, the drum cartridge to which the developing cartridge has been attached is attached to the main casing of the image forming apparatus.

The image forming apparatuses disclosed in the related art are switchable between a state in which the developing roller and the photosensitive drum are in contact with each other and a state in which the developing roller and the photosensitive drum are separated from each other. In the related art, parts for moving the developing cartridge to separate the developing roller from the photosensitive drum are provided at both ends of the drawer unit or the drum cartridge, and both parts for moving the developing cartridge need to be removed from the main body of the image forming apparatus Receive driving force.

SUMMARY OF THE INVENTION

In view of the foregoing, an object of the present disclosure is to provide an image forming apparatus capable of moving a developing cartridge relative to a photosensitive drum of a drawer by a driving force acting only on one end of the developing cartridge, not by a driving force acting on the developing cartridge driving force on both ends.

To achieve the above and other objects, the present disclosure provides an image forming apparatus including: a developing cartridge; a photosensitive drum; a drawer; a pressing member; and a driving unit. The developing cartridge includes a developing roller having an outer peripheral surface. The photosensitive drum is rotatable about a rotation axis extending in the axial direction. The photosensitive drum has an outer peripheral surface. The drawer includes the frame. The developing cartridge can be attached to the frame in a state where the outer circumferential surface of the developing roller faces the outer circumferential surface of the photosensitive drum. The frame movably supports the developing cartridge, and at least a part of the developing cartridge is movable in the axial direction. The frame is configured to move the developing cartridge in the separation direction in response to movement in the axial direction of at least a portion of the developing cartridge attached to the frame. The separation direction is the direction in which the outer circumferential surface of the developing roller is separated from the outer circumferential surface of the photosensitive drum. The pressing member has a cylindrical shape extending in the axial direction, and is movable in the axial direction between a contact position and a non-contact position. The pressing member in the contact position is in contact with the developing cartridge, and is configured to press the developing cartridge in the axial direction to move the developing cartridge in the axial direction. The pressing member in the non-contact position is separated from the developing cartridge. The driving unit is configured to move the pressing member in the axial direction between the contact position and the non-contact position.

Preferably, the drawer includes a photosensitive drum.

Preferably, the drawer has an opening through which the pressing member can move between a contact position and a non-contact position.

Preferably, the developing cartridge has a portion movably supported to the frame. The frame is configured to move the developing cartridge in the separation direction in response to movement in the axial direction of the portion of the developing cartridge attached to the frame.

Preferably, the frame includes: a first side frame; and a second side frame spaced apart from the first side frame in the axial direction. The developing cartridge can be attached to the frame between the first side frame and the second side frame in the axial direction. The second side frame has a through hole penetrating the second side frame in the axial direction. The through hole allows a portion of the developing cartridge attached to the frame to be exposed to the outside of the frame, and allows the pressing member to move therefrom between a contact position and a non-contact position.

Preferably, the separation direction intersects the axial direction.

Preferably, the image forming apparatus further includes a main frame to which the drawer can be detachably attached.

Preferably, the image forming apparatus further includes another developing cartridge including another developing roller. The frame includes another photosensitive drum. The developing cartridge can be attached to the frame corresponding to the photosensitive drum. Another developing cartridge can be attached to the frame corresponding to the other photosensitive drum.

According to another aspect, the present disclosure provides an image forming apparatus including: a developing cartridge; a drum cartridge; a pressing member; and a driving unit. The developing cartridge includes a developing roller having an outer peripheral surface. The drum cartridge includes: a photosensitive drum; and a frame. The photosensitive drum is rotatable about a rotation axis extending in the axial direction. The photosensitive drum has an outer peripheral surface. The developing cartridge can be attached to the frame in a state where the outer circumferential surface of the developing roller faces the outer circumferential surface of the photosensitive drum. The frame movably supports the developing cartridge, and at least a part of the developing cartridge is movable in the axial direction. The frame is configured to move the developing cartridge in the separation direction in response to movement in the axial direction of at least a portion of the developing cartridge attached to the frame. The separation direction is the direction in which the outer circumferential surface of the developing roller is separated from the outer circumferential surface of the photosensitive drum. The pressing member has a cylindrical shape extending in the axial direction, and is movable in the axial direction between a contact position and a non-contact position. The pressing member in the contact position is in contact with the developing cartridge. The pressing member in the non-contact position is separated from the developing cartridge. The driving unit is configured to move the pressing member in the axial direction between the contact position and the non-contact position.

Preferably, the drum cartridge has an opening through which the pressing member can move between a contact position and a non-contact position.

Preferably, the developing cartridge has a portion movably supported to the frame. The frame is configured to move the developing cartridge in the separation direction in response to movement in the axial direction of the portion of the developing cartridge attached to the frame.

Preferably, the frame includes: a first side frame; and a second side frame, the second side frame being spaced apart from the first side frame in the axial direction. The developing cartridge can be attached to the frame between the first side frame and the second side frame in the axial direction. The second side frame has a through hole penetrating the second side frame in the axial direction. The through hole allows a portion of the developing cartridge attached to the frame to be exposed to the outside of the frame, and allows the pressing member to move therefrom between a contact position and a non-contact position.

Preferably, the separation direction intersects the axial direction.

Preferably, the image forming apparatus further includes a main frame to which the drum cartridge can be detachably attached.

Preferably, the image forming apparatus further includes another developing cartridge, and the other developing cartridge includes another developing roller. The drum cartridge includes another photosensitive drum disposed in the frame. The developing cartridge can be attached to the frame corresponding to the photosensitive drum. Another developing cartridge can be attached to the frame corresponding to the other photosensitive drum.

Description of drawings

Particular features and advantages, as well as other objects of the embodiments, will become apparent from the following description taken in conjunction with the accompanying drawings, wherein:

1 is a schematic diagram of an image forming apparatus including a developing cartridge according to a first embodiment of the present disclosure;

2 is a perspective view of the developing cartridge according to the first embodiment;

3 is another perspective view of the developing cartridge according to the first embodiment;

4 is a plan view of the developing cartridge according to the first embodiment, as viewed in a first direction;

Fig. 5 is another plan view of the developing cartridge according to the first embodiment viewed in the first direction;

6 is an exploded perspective view of a separation member of the developing cartridge according to the first embodiment;

7 is an exploded enlarged view of the shaft and first cam of the separation member;

8 is a view for describing the movement of the separation member in the first direction with respect to the housing of the developing cartridge and the developing roller according to the first embodiment;

9 is another view for describing the movement of the separation member relative to the housing and the developing roller in the first direction;

Fig. 10 is a plan view of the developing cartridge according to the first embodiment viewed in a third direction;

11 is a perspective view of the drawer to which the developing cartridge according to the first embodiment is detachably attached;

Figure 12 is a plan view of the drawer viewed in a third direction;

13 is a perspective view of the drawer and the developing cartridge according to the first embodiment, showing a state in which the developing cartridge is attached to the drawer;

14 is a plan view of the drawer and the developing cartridge according to the first embodiment, as viewed in a third direction, showing a state in which the developing cartridge is attached to the drawer;

15 is a plan view of the drawer and the developing cartridge according to the first embodiment, as viewed in the first direction, showing a state in which the developing cartridge is attached to the drawer;

16A is a view for describing the separation movement of the developing cartridge according to the first embodiment performed by the separation member;

16B is another view for describing the separation movement of the developing cartridge according to the first embodiment performed by the separation member;

17 is a perspective view of the developing cartridge and the photosensitive drum of the drawer in the contact state of the image forming apparatus according to the first embodiment;

18 is a perspective view of the developing cartridge and the photosensitive drum in a separated state of the image forming apparatus according to the first embodiment;

19 is a plan view of the developing cartridge according to the second embodiment of the present disclosure as viewed in the third direction;

20A is a view for describing the separation movement of the developing cartridge according to the second embodiment performed by the separation member; and

FIG. 20B is another view for describing the separation movement of the developing cartridge according to the second embodiment performed by the separation member.

Detailed ways

<1. First Embodiment>

Hereinafter, the image forming apparatus 100 including the developing cartridge 1 according to the first embodiment will be described with reference to FIGS. 1 to 18 .

<1.1. Configuration of Image Forming Apparatus>

FIG. 1 is a schematic diagram of an image forming apparatus 100 . The image forming apparatus 100 is an electrophotographic type printer. For example, the image forming apparatus 100 may be a laser printer or an LED printer.

The image forming apparatus 100 includes four developing cartridges 1 , a drawer 2 , a main frame 101 and a controller 102 .

The developing cartridge 1 is attachable to the drawer 2 . That is, the developing cartridge 1 is used together with the drawer 2 . The drawer 2 is a drum cartridge to which four developing cartridges 1 can be attached, and includes four slots 2A. Four developing cartridges 1 are attachable to the corresponding slots 2A. The developing cartridge 1 may be attached to the main frame 101 in a state in which the developing cartridge 1 is attached to the corresponding groove 2A. That is, in a state where the developing cartridge 1 is attached to the corresponding slot 2A, the drawer 2 is detachably attached to the main frame 101 . The four developing cartridges 1 contain developers (eg, toners) of mutually different colors (eg, cyan, magenta, yellow, and black). However, a plurality of developing cartridges 1 can accommodate developers of the same color. The number of developing cartridges 1 attachable to the drawer 2 may be one, two, or three, or five or more.

The image forming apparatus 100 is configured to form an image on printing paper using the developer supplied from the four developing cartridges 1 .

Each of the four developing cartridges 1 includes an IC chip 51 . The IC chip 51 is a storage medium from which information can be read and from which information can be written. For example, the storage medium may be flash ROM or EEPROM. When the developing cartridge 1 attached to the slot 2A of the drawer 2 is attached to the main frame 101, the IC chip 51 of the developing cartridge 1 and the controller 102 are electrically connected to each other. The controller 102 is constituted by, for example, a circuit board. The controller 102 includes a processor such as a CPU and various memories. The controller 102 is configured to execute various types of processing in the image forming apparatus 100 by operating a processor according to a program.

<1.2. Developer cartridge>

2 and 3 are perspective views of the developing cartridge 1 . 4 and 5 are plan views of the developing cartridge 1 viewed in the first direction.

In the following description, the direction in which the rotation axis (ie, the first axis) of the developing roller 30 extends will be referred to as a "first direction" (an example of an axial direction). The first direction also means the direction in which the rotation axis (drum axis) of the photosensitive drum 21 (described later) of the drawer 2 extends. Here, the outer circumferential surface of the developing roller 30 includes one end portion exposed to the outside of the casing 10 , and the other end portion located inside the casing 10 . The direction in which one end portion of the circumferential surface of the developing roller 30 and the other end portion of the circumferential surface are aligned is referred to as a "second direction" (an example of a separation direction). The second direction also means a direction intersecting the circumferential surface of the developing roller 30 exposed to the outside of the casing 10 of the developing cartridge 1 . The second direction may represent a direction in which the outer circumferential surface of the developing roller 30 is separated from and/or approached by the outer circumferential surface of the photosensitive drum 21 (described later). The first direction and the second direction intersect with each other. Preferably, the first direction and the second direction are perpendicular to each other.

The developing cartridge 1 includes a housing 10 configured to accommodate a developer therein. The housing 10 has a first outer surface 11 and a second outer surface 12, which are separated from each other in a first direction. The housing 10 extends in the first direction between the first outer surface 11 and the second outer surface 12 . That is, the first outer surface 11 is one end of the casing 10 in the first direction, and the second outer surface 12 is the other end of the casing 10 in the first direction.

The housing 10 includes a container 10A and a lid 10B. The container 10A is configured to accommodate the developer therein, and has an opening (not shown). The lid 10B covers the opening (not shown) of the container 10A. The container 10A and the lid 10B are arranged at a position between the first outer surface 11 and the second outer surface 12 in the first direction.

The housing 10 also extends in a predetermined direction. Hereinafter, the predetermined direction in which the housing 10 extends will be referred to as a "third direction". The third direction intersects the first direction. Preferably, the third direction is perpendicular to the first direction. The third direction may represent the direction in which the developing cartridge 1 is inserted into the corresponding groove 2A of the drawer 2 (see FIG. 1 ) and/or withdrawn from the corresponding groove 2A of the drawer 2 . The housing 10 has an opening 10C. The opening 10C is positioned at one end portion of the housing 10 in the third direction.

The developing cartridge 1 also includes an agitator 20 . The agitator 20 is rotatable about an axis extending in the first direction (ie, the third axis). The agitator 20 is a member configured to agitate the developer contained in the container 10A. The agitator 20 includes a shaft extending in a first direction, and agitating blades extending radially outward from the shaft. As the shaft rotates, the developer contained in the container 10A is stirred by the stirring blades.

The developing cartridge 1 also includes a developing roller 30 . The developing roller 30 is spaced apart from the agitator 20 in the second direction. Further, the agitator 20 is positioned to be closer to the developing roller 30 in the second direction than the shaft 61 (described later) is to the developing roller 30 . The developing roller 30 is located at the opening 10C, which is located at one end of the casing 10 in the third direction. The developing roller 30 is supported by the housing 10 so as to be a roller rotatable about a first axis extending in the first direction.

The developing roller 30 includes a developing roller body 31 and a developing roller shaft 32 . The developing roller body 31 has a hollow cylindrical shape extending in the first direction. The developing roller body 31 is made of an elastic material such as rubber. The developing roller shaft 32 has a columnar shape extending through the developing roller body 31 in the first direction. The developing roller shaft 32 is made of conductive metal or resin. The developing roller body 31 is fixed to the developing roller shaft 32 so as not to rotate relative to the developing roller shaft 32 . With this configuration, the developing roller body 31 can rotate together with the developing roller shaft 32 . The developing roller 30 (ie, the developing roller body 31 ) is at least partially exposed to the outside of the casing 10 . That is, at least a part of the outer circumferential surface of the developing roller 30 is exposed to the outside of the casing 10 . More specifically, one end portion of the outer circumferential surface of the developing roller body 31 in the second direction is exposed to the outside of the casing 10 through the opening 10C. The other end portion in the second direction of the outer circumferential surface of the developing roller body 31 is positioned within the casing 10 . That is, the other end portion of the outer circumferential surface of the developing roller body 31 in the second direction is not exposed to the outside of the casing 10 .

The developing cartridge 1 also includes a developing electrode 33 . The developing electrode 33 is located at one end of the developing roller shaft 32 in the first direction. Here, the developing roller shaft 32 provided with the developing electrode 33 is rotatably attached to a bearing (not shown) of the housing 10 . The bearing may be integrally formed at the housing 10 , or may be formed separately from the housing 10 . The developing electrode 33 is located at the first outer surface 11 . The developing electrode 33 is electrically connected to the developing roller shaft 32 of the developing roller 30 . The developing electrode 33 is an electrode for applying a developing bias to the developing roller 30 . The developing electrode 33 is positioned closer to the developing roller 30 in the second direction than the shaft 61 and the first cam 62 of the separation member 60 (described later) are from the developing roller 30 .

A developing roller gear (not shown) is coupled to the other end portion of the developing roller shaft 32 in the first direction. The developer roller gear is located at the second outer surface 12 . The developing roller shaft 32 is fixed to the developing roller gear so as not to rotate relative to the developing roller gear. When the developing roller gear rotates, the developing roller shaft 32 also rotates so that the developing roller body 31 rotates together with the developing roller shaft 32 .

Incidentally, the developing roller shaft 32 may not extend through the developing roller body 31 in the first direction. For example, each of the pair of developing roller shafts 32 may extend in the first direction from each end portion of the developing roller body 31 in the first direction.

The developing cartridge 1 also includes a supply roller (not shown). The supply roller is arranged in the container 10A at a position between the developing roller 30 and the agitator 20 . The supply roller is rotatable about an axis of rotation extending in the first direction. When the developing cartridge 1 receives the driving force, the developer is supplied from the container 10A of the casing 10 to the outer circumferential surface of the developing roller 30 (ie, the outer circumferential surface of the developing roller body 31 ) through the supply roller. At this time, the developer is triboelectrically charged between the supply roller and the developing roller 30 . At the same time, a developing bias is applied to the developing roller shaft 32 of the developing roller 30 . Therefore, the developer is attracted to the outer circumferential surface of the developing roller body 31 by the electrostatic force generated between the developing roller shaft 32 and the developer.

The developing cartridge 1 also includes a layer thickness regulating blade (not shown). The layer thickness adjusting blade adjusts the thickness of the developer layer supplied on the outer circumferential surface of the developing roller body 31 so that the thickness of the developer layer is formed to be a constant thickness. The developer on the outer circumferential surface of the developing roller body 31 is then supplied to the photosensitive drum 21 of the drawer 2 (described later, see FIG. 11 ). At this time, the developer is transferred from the developing roller body 31 to the photosensitive drum 21 according to the electrostatic latent image formed on the outer circumferential surface of the photosensitive drum 21 . Therefore, the electrostatic latent image formed on the outer circumferential surface of the photosensitive drum 21 becomes a visible image.

As shown in FIGS. 3 and 4 , the developing cartridge 1 further includes a gear portion 40 . The gear portion 40 is positioned at the second outer surface 12 of the housing 10 . The gear portion 40 includes a coupling 41 and a developing roller gear (not shown).

The coupling 41 is a gear that receives a driving force applied from the main frame 101 of the image forming apparatus 100 . The coupling 41 is rotatable about a rotation axis extending in the first direction. The coupling 41 is positioned closer to the developing roller 30 in the second direction than the shaft 61 , the first cam 62 and the second cam 63 of the separation member 60 (described later) are from the developing roller 30 . The coupling 41 has a coupling hole 411 recessed in the first direction. When the developing cartridge 1 attached to the slot 2A of the drawer 2 is attached to the main frame 101 of the image forming apparatus 100 , a drive shaft (not shown) of the image forming apparatus 100 is inserted into the coupling hole 411 . Therefore, the drive shaft and the coupling 41 are coupled to each other, thereby preventing relative rotation between the drive shaft and the coupling 41 . Therefore, when the drive shaft rotates, the coupling 41 also rotates. Further, as the coupling 41 is rotated, the supply shaft and the developing roller gear connected to the supply roller (not shown) are rotated. By this rotation, the supply roller rotates together with the supply shaft, and the developing roller 30 rotates together with the developing roller gear. Rotation of coupling 41 also causes agitator 20 to rotate through another gear (not shown).

The image forming apparatus 100 has a contact state and a separation state. In the contact state of the image forming apparatus 100 , the developing roller 30 and the photosensitive drum 21 of the drawer 2 are in contact with each other in a state where the developing cartridge 1 is attached to the groove 2A of the drawer 2 . In the separated state of the image forming apparatus 100, the developing roller 30 and the photosensitive drum 21 of the drawer 2 are separated from each other. When the developing cartridge 1 is attached to the groove 2A of the drawer 2, the image forming apparatus 100 is in a contact state.

The developing cartridge 1 further includes a separation member 60 . The separation member 60 is a member for switching the state of the image forming apparatus 100 between the contact state and the separation state. In the present embodiment, when the image forming apparatus 100 is switched from the contact state to the separation state, the developing roller 30 is separated from the photosensitive drum 21 in the second direction, which is the separation direction in which the developing roller 30 is separated from the photosensitive drum 21 .

The separation member 60 is arranged at the cover 10B. The separation member 60 is movable in the first direction relative to the housing 10 and the developing roller 30 . In addition, the separation member 60 is movable in the second direction together with the housing 10 and the developing roller 30 .

FIG. 6 is an exploded perspective view of the separation member 60 . In the housing 10 , only the cover 10B in which the separation member 60 is arranged is shown in FIG. 6 . FIG. 7 is an exploded enlarged view of the shaft 61 and the first cam 62 in the separation member 60 . 8 and 9 are views for describing the movement of the separation member 60 in the first direction with respect to the casing 10 and the developing roller 30 . FIG. 10 is a plan view of the developing cartridge 1 viewed in the third direction. Hereinafter, the separation member 60 will be described with reference to FIGS. 2 to 10 .

The separation member 60 includes a shaft 61 extending along an axis extending in the first direction (ie, the second axis). The shaft 61 has a cylindrical shape. However, the shaft 61 may have a rectangular cylindrical shape. The cover 10B has a groove 10B1, a hole 10B4 and a hole 10B5, each of which penetrates the cover 10B in the first direction. The diameter of each of the groove 10B1 , the hole 10B4 and the hole 10B5 is larger than the diameter of the shaft 61 . The shaft 61 is inserted through the groove 10B1, the hole 10B4 and the hole 10B5. The shaft 61 inserted into the groove 10B1, the hole 10B4 and the hole 10B5 can be relative to the housing 10 between the first position (the position shown in FIG. 8 ) and the second position (the position shown in FIG. 9 ). The cover 10B moves in the first direction. The shaft 61 in the second position is closer to the first outer surface 11 than the shaft 61 in the first position is from the first outer surface 11 . Note that although the cover 10B has two holes (ie, the hole 10B4 and the hole 10B5 ) in the present embodiment, the cover 10B may have at least one hole as long as the cover 10B can movably support the shaft 61 .

Preferably, the shaft 61 is made of a rigid material. For example, the shaft 61 is made of iron. Alternatively, the shaft 61 may be made of resin.

In this embodiment, the housing 10 includes annular portions 10B2 and 10B3. The annular portion 10B2 is formed at one end portion of the cover 10 in the first direction, and the annular portion 10B3 is formed at the other end portion of the cover 10B in the first direction. The annular portions 10B2 and 10B3 are integrally formed at the cover 10B. The through hole passing through the annular portion 10B2 is the hole 10B4, and the through hole passing through the annular portion 10B3 is the hole 10B5. The groove 10B1 formed along the first direction is exposed between the annular portion 10B2 and the annular portion 10B3. That is, the shaft 61 inserted into the groove 10B1, the hole 10B4 and the hole 10B5 is exposed from the cover 10B at a position between the annular portion 10B2 and the annular portion 10B3. Since the shaft 61 has rigidity, a part of the shaft 61 exposed from the cover 10B is not bent toward the second direction or the third direction (ie, directions other than the first direction).

Incidentally, only one annular portion may be formed at the cover 10B. Alternatively, further annular portions may be arranged between annular portions 10B2 and 10B3. Although the shaft 61 is exposed at a position between the annular portions 10B2 and 10B3 in the first direction in the present embodiment, the shaft 61 may not be exposed from the cover 10B. That is, the shaft 61 can be accommodated in the cover 10B.

As described above, the shaft 61 is supported by the cover 10B so as to be movable in the first direction along the second axis. Therefore, the shaft 61 can be easily arranged at the housing 10 .

The first cam 62 is arranged at one end portion 61A of the shaft 61 in the first direction. The first cam 62 is made of, for example, rubber or resin. As shown in FIG. 7 , the first cam 62 has a hole 62A penetrating the first cam 62 in the first direction. The diameter of one end portion 61A of the shaft 61 is smaller than the diameter of the portion of the shaft 61 other than the one end portion 61A. One end portion 61A of the shaft 61 is inserted into the hole 62A. One end portion 61A in the insertion hole 62A has a distal end exposed from the first cam 62 in the first direction, and the retaining ring 61B is attached to the exposed distal end of the one end portion 61A. With this configuration, the first cam 62 is fixed to the one end portion 61A of the shaft 61 . Alternatively, the first cam 62 may be adhesively fixed to the shaft 61 .

The first cam 62 has a first inclined surface 621 that is not parallel to the second axis. In the present embodiment, the first inclined surface 621 is positioned at a part of the outer peripheral surface of the shaft 61 as shown in FIG. 5 . More specifically, the first inclined surface 621 is positioned at one end portion of the shaft 61 in the second direction. One end portion of the shaft in the second direction is closer to the developing roller 30 than the other end portion of the shaft 61 in the second direction is closer to the developing roller 30 . The first cam 62 also has a contact surface 622 facing the cover 10B. The contact surface 622 is arranged at another portion of the outer peripheral surface of the shaft 61 that is different from the portion of the outer peripheral surface where the first inclined surface 621 is located. In other words, the contact surface 622 faces the housing 10 , ie, the outer surface of the housing 10 . Since the contact surface 622 faces the cover 10B, even if the first cam 62 attempts to rotate about the shaft 61, the contact surface 622 contacts the cover 10B, thereby preventing the first cam 62 from rotating. Although the first inclined surface 621 is arranged at a part of the outer peripheral surface of the shaft 61 in the present embodiment, the first inclined surface 621 may be arranged at the entire outer peripheral surface of the shaft 61 .

The first inclined surface 621 is inclined with respect to the shaft 61 extending in the first direction and is angled with respect to the second axis. In other words, the first inclined surface 621 is inclined with respect to the direction connecting one end portion of the outer circumferential surface of the developing roller 30 and the other end portion of the outer circumferential surface of the developing roller 30 . The angle between the first inclined surface 621 and the first direction is greater than or equal to 43 degrees and less than or equal to 47 degrees. More preferably, the angle between the first inclined surface 621 and the first direction is about 45 degrees.

The first cam 62 , ie, the first inclined surface 621 is positioned at the first outer surface 11 of the housing 10 . When the first inclined surface 621 extends in a direction away from the first outer surface 11 in the first direction, the first inclined surface 621 extends away from the developing roller 30 in the second direction. That is, the first inclined surface 621 is formed such that the distance between the shaft 61 (ie, the second axis) and the first inclined surface 621 in the radial direction of the shaft 61 (ie, the second direction) is the same as the distance from the shaft 61 One end portion 61A in the first direction increases in the direction of the other end portion of the shaft 61 in the first direction. In other words, the first inclined surface 621 is inclined with respect to the first direction such that the distance between the first inclined surface 621 and the shaft 61 in the direction perpendicular to the first axis is from one end of the shaft 61 in the first direction The portion 61A increases toward the other end portion of the shaft 61 in the first direction. In other words, the first inclined surface 621 is inclined with respect to the first direction so that the distance between the first inclined surface 621 and the developing roller 30 in the second direction increases or decreases in the first direction with respect to the casing 10 Small. In further words, the first inclined surface 621 is inclined with respect to the first direction such that one end of the first inclined surface 621 in the first direction is farther from the axis 61 than the other end of the first inclined surface 621 in the first direction is farther from the axis 61 is closer. The first inclined surface 621 is inclined at an acute angle with respect to the shaft 61 .

The first cam 62 is formed like a half of a cone centered on the second axis. In other words, the first cam 62 has a portion of the circumferential surface of the cone serving as the first inclined surface 621 .

Note that the first cam 62 may have a pyramid shape instead of a taper. In this case, the second axis passes through the apex and the center of the bottom surface of the pyramid, and a part of the side surface of the pyramid serves as the first inclined surface 621 . Further, although the first inclined surface 621 is smoothly inclined with respect to the shaft 61 in the present embodiment, the first inclined surface 621 may have protrusions and concave portions such as steps. Alternatively, the first inclined surface 621 may be curved.

The second cam 63 is arranged at the other end portion of the shaft 61 in the first direction. The second cam 63 is made of, for example, rubber or resin. Similar to the first cam 62 described with reference to FIG. 7 , the second cam 63 is fixed to the other end portion of the shaft 61 in the first direction.

The second cam 63 has a second inclined surface 631 that is not parallel to the second axis. In the present embodiment, the second inclined surface 631 is located at the entire outer peripheral surface of the shaft 61 as shown in FIG. 4 . Incidentally, the second inclined surface 631 may be arranged at a part of the outer peripheral surface of the shaft 61 . In this case, the second inclined surface 631 is positioned at one end portion of the shaft 61 in the second direction, that is, an end portion positioned closer to the developing roller 30 than the other end portion.

The second inclined surface 631 is inclined with respect to the shaft 61 extending in the first direction and is angled with respect to the second axis. In other words, the second inclined surface 631 is inclined with respect to the direction connecting one end portion of the outer circumferential surface of the developing roller 30 and the other end portion of the outer circumferential surface of the developing roller 30 . The angle between the second inclined surface 631 and the first direction is greater than or equal to 43 degrees and less than or equal to 47 degrees. More preferably, the angle between the second inclined surface 631 and the first direction is about 45 degrees.

The second inclined surface 631 is formed such that the distance between the shaft 61 (ie, the second axis) and the second inclined surface 631 in the radial direction of the shaft 61 (ie, the second direction) is the same as the distance from the shaft 61 in the first direction The upward one end portion 61A increases in the direction of the other end portion of the shaft 61 in the first direction. In other words, the second inclined surface 631 is inclined with respect to the first direction such that the distance between the second inclined surface 631 and the shaft 61 in the direction perpendicular to the first axis is from one end of the shaft 61 in the first direction The portion 61A increases to the other end portion of the shaft 61 in the first direction. In further other words, the second inclined surface 631 is inclined with respect to the first direction so that the distance in the second direction between the second inclined surface 631 and the developing roller 30 increases in the first direction with respect to the casing 10 or decrease. In further other words, the second inclined surface 631 is inclined with respect to the first direction such that in the second direction, one end of the second inclined surface 631 in the first direction is more distant from the axis 61 than the second inclined surface 631 is in the first direction The other end upwards is closer to the axis 61 . The second inclined surface 631 is inclined at an acute angle with respect to the shaft 61 . That is, the first inclined surface 621 of the first cam 62 and the second inclined surface 631 of the second cam 63 are inclined in the same direction with respect to the first direction.

The radial distance from the second axis to the second inclined surface 631 increases as the distance from the first inclined surface 621 to the second inclined surface 631 increases, and the radial distance from the second axis to the first inclined surface 621 It decreases as the distance from the first inclined surface 621 to the second inclined surface 631 increases.

The second cam 63 has a tapered shape centered on the second axis. In other words, the second cam 63 has a part of the circumferential surface of the cone serving as the second inclined surface 631 .

The second cam 63 may have a pyramid shape instead of a tapered shape. In this case, the second axis passes through the vertex and the center of the bottom surface of the pyramid, and a part of the side surface of the pyramid serves as the second inclined surface 631 . In the present embodiment, the second inclined surface 631 is smoothly inclined with respect to the shaft 61 . However, the second inclined surface 631 may have a protruding or recessed portion such as a step. Alternatively, the second inclined surface 631 may be curved.

As shown in FIGS. 8 and 9 , both the first cam 62 and the second cam 63 can move together with the shaft 61 in the first direction. That is, both the first cam 62 and the second cam 63 can move axially together with the shaft 61 along the second axis in response to the axial movement of the shaft 61 in the first direction. When the shaft 61 moves from the first position to the second position in the first direction, the second cam 63 approaches the cover 10B, and the first cam 62 retreats from the cover 10B. When the shaft 61 moves from the second position to the first position in the first direction, the second cam 63 retreats from the cover 10B, and the first cam 62 approaches the cover 10B. In other words, when the shaft 61 moves from the first position to the second position in the first direction, the second cam 63 approaches the housing 10 and the first cam 62 moves away from the housing 10. When the shaft 61 moves from the second position to the first position in the first direction, the second cam 63 moves away from the housing 10 and the first cam 62 approaches the housing 10 .

In the present embodiment, the contact surface 622 of the first cam 62 faces the cover 10B, and this configuration prevents the first cam 62 from rotating. Therefore, the shaft 61 to which the first cam 62 is fixed and the second cam 63 to which the shaft 61 is fixed are also unable to rotate relative to the cover 10B. That is, the shaft 61 inserted through the holes 10B5 and 10B4 cannot rotate about the second axis extending in the first direction with respect to the cover 10B of the housing 10 . However, the shaft 61 is rotatable relative to the cover 10B about a second axis extending in the first direction. In the case where the shaft 61 is configured to be rotatable with respect to the first cam 62 and the second cam 63, only the shaft 61 rotates with respect to the cover 10B, the first cam 62 and the second cam 63, and the first cam 62 and the second cam 63 does not rotate. Alternatively, the shaft 61 may rotate about the second axis together with the first cam 62 and the second cam 63 .

The separation member 60 also includes a coil spring 64 . The coil spring 64 is positioned at the other end portion of the shaft 61 in the first direction. Specifically, the shaft 61 is inserted into the coil spring 64 . The coil spring 64 is located between the second cam 63 and the cover 10B in the first direction. One end of the coil spring 64 in the first direction is in contact with the cover 10B through, for example, a gasket 65 . The other end of the coil spring 64 in the first direction is in contact with the second cam 63 . That is, one end of the coil spring 64 is connected to the housing 10 , and the other end of the coil spring 64 is connected to the second inclined surface 631 . The coil spring 64 is covered by the cover 66 in the circumferential direction of the shaft 61 . Although the coil spring 64 is connected to the shaft 61 through the second cam 63 , the coil spring 64 may be directly connected to the shaft 61 .

The coil spring 64 is an elastic member configured to expand and contract in a first direction between a first length and a second length shorter than the first length. As will be described in detail later, the second cam 63 is pressed by the pressure applied in the direction from the other end portion of the shaft 61 in the first direction to the one end portion 61A of the shaft 61 . Therefore, the shaft 61 moves from the first position shown in FIG. 8 to the second position shown in FIG. 9 together with the first cam 62 and the second cam 63 . When the shaft 61 moves from the first position to the second position, the coil spring 64 compresses from the first length to the second length. When the pressure applied to the second cam 63 is released, due to the restoring force of the coil spring 64, the coil spring 64 is restored from the second length to the first length, whereby the shaft 61 together with the first cam 62 and the second cam 63 from the first The second position is moved back to the first position. In this way, the shaft 61 , the first cam 62 and the second cam 63 can move in the first direction relative to the housing 10 due to the pressure applied in the first direction and the elastic force (restoring force) of the coil spring 64 .

<1.3. Drawer>

FIG. 11 is a perspective view of the drawer 2 . FIG. 12 is a plan view of the drawer 2 viewed in the third direction. FIG. 13 is a perspective view of the drawer 2 and the developing cartridge 1 , showing a state in which the developing cartridge 1 is attached to the corresponding groove 2A of the drawer 2 . 14 is a plan view of the drawer 2 and the developing cartridge 1 viewed in the third direction, showing a state in which the developing cartridge 1 is attached to the corresponding groove 2A of the drawer 2 . 15 is a plan view of the drawer 2 and the developing cartridge 1 viewed in the first direction, showing a state in which the developing cartridge 1 is attached to the corresponding groove 2A of the drawer 2 .

The drawer 2 includes a frame 200 . The frame 200 includes four slots 2A. The developing cartridges 1 are respectively attachable to the corresponding grooves 2A. The drawer 2 also includes a photosensitive drum 21 . Each photosensitive drum 21 is arranged corresponding to each of the four grooves 2A. Each photosensitive drum 21 is rotatable about a rotation axis (drum axis) extending in the first direction. The frame 200 movably supports the separation member 60 of each developing cartridge 1 in a state where each developing cartridge 1 is attached to the corresponding groove 2A. Each developing cartridge 1 may be attached to the corresponding groove 2A of the drawer 2 so that the outer circumferential surface of the developing roller 30 faces the outer circumferential surface of the photosensitive drum 21 . More specifically, each developing cartridge 1 may be attached to the corresponding groove 2A of the drawer 2 in a state in which the outer circumferential surface of the developing roller 30 contacts the outer circumferential surface of the photosensitive drum 21 .

Note that the drawer 2 includes conventional (well known) push members. In a state where each developing cartridge 1 is attached to the groove 2A, the developing roller 30 and the corresponding photosensitive drum 21 of each developing cartridge 1 contact each other in the second direction due to the urging force applied by the conventional urging member. The drawer 2 in which the developing cartridge 1 has been attached to each slot 2A is attached to the main frame 101 (see FIG. 1 ).

In a state where each developing cartridge 1 is attached to the frame 200 of the drawer 2, the frame 200 is configured to move the developing roller 30 of the attached developing cartridge 1 in the second direction. That is, the frame 200 may move the developing roller 30 in the second direction in response to the movement of the separation member 60 in the first direction in a state where the outer circumferential surface of the developing roller 30 is in contact with the outer circumferential surface of the photosensitive drum 21, In the second direction, the developing rollers 30 are separated from the corresponding photosensitive drums 21 .

The frame 200 of the drawer 2 includes a first side frame 201 and a second side frame 202 . The first side frame 201 and the second side frame 202 are spaced apart from each other in the first direction. The four photosensitive drums 21 are arranged at positions between the first side frame 201 and the second side frame 202 in the first direction. When the developing cartridge 1 is attached to the groove 2A, the developing cartridge 1 is positioned between the first side frame 201 and the second side frame 202 in the first direction. In this state, the first outer surface 11 of each developing cartridge 1 faces the first side frame 201 in the first direction, and the second outer surface 12 of each developing cartridge 1 faces the first side frame 201 in the first direction Two side frames 202 .

The first side frame 201 has a first recessed portion 201A formed corresponding to each of the four grooves 2A. Each of the first recessed portions 201A penetrates the first side frame 201 in the first direction, and is recessed toward the corresponding photosensitive drum 21 in the third direction. In a state where each developing cartridge 1 is attached to the corresponding groove 2A of the drawer 2 , the IC chip 51 of each developing cartridge 1 covered with the cover 45 is located in the corresponding first recessed portion 201A, as shown in FIGS. 13 and 14 . Show.

The second side frame 202 has a second recessed portion 202A (as an example of a through hole and an opening). Similar to the first recessed portion 201A, each of the second recessed portions 202A is formed corresponding to each of the grooves 2A. Each second recessed portion 202A penetrates the second side frame 202 in the first direction to expose a portion of the developing cartridge 1 to the outside of the drawer 2, and opens toward a direction away from the corresponding photosensitive drum 21 in the third direction. In a state where each developing cartridge 1 is attached to the corresponding groove 2A of the drawer 2 , the second cam 63 of each developing cartridge 1 is located in the corresponding second recessed portion 202A, as shown in FIGS. 13 to 15 .

The second side frame 202 also has through holes 202B. Each through hole 202B is formed corresponding to each groove 2A. Each through hole 202B penetrates the second side frame 202 in the first direction. In a state where each developing cartridge 1 is attached to the corresponding groove 2A of the drawer 2 , the coupling hole 411 of the coupling 41 of each developing cartridge 1 is exposed from the corresponding through hole 202B, as shown in FIGS. 13 to 15 . The drive shaft of the image forming apparatus 100 is inserted into each coupling hole 411 through the corresponding through hole 202B. Therefore, the drive shaft and the corresponding coupling 41 are coupled to each other so as not to rotate relative to each other.

The drawer 2 has a first receiving surface 22 and a second receiving surface 23 for each slot 2A. The first receiving surface 22 is spaced apart from the second receiving surface 23 in the first direction. That is, the first receiving surface 22 is located at one end portion of each groove 2A in the first direction, and the second receiving surface 23 is located at the other end portion of each groove 2A in the first direction.

Each of the first receiving surfaces 22 is positioned at a surface of the first side frame 201 facing the second side frame 202 . The first receiving surface 22 is inclined with respect to the first direction. More specifically, the first receiving surface 22 is arranged to face the first cam 62 of the developing cartridge 1 attached to the groove 2A of the drawer 2 in the second direction. The first receiving surface 22 contacts the first inclined surface 621 of the first cam 62 as shown in FIG. 14 . The first receiving surface 22 is formed such that the distance between the first receiving surface 22 and the developing cartridge 1 in the second direction is in the direction away from the first side frame 201 in the first direction (ie, from the first direction in the first direction). increase in the direction from one side frame 201 to the second side frame 202). The first receiving surface 22 is an example of a first inclined surface.

The second receiving surface 23 is positioned at each of the second recessed portions 202A formed at the second side frame 202 . The second receiving surface 23 is inclined with respect to the first direction in the same direction as the first receiving surface 22 . More specifically, the second receiving surface 23 is arranged such that the second receiving surface 23 faces the second cam 63 of the developing cartridge 1 attached to each groove 2A of the drawer 2 . The second receiving surface 23 contacts the second inclined surface 631 of the second cam 63 as shown in FIG. 14 . The second receiving surface 23 is formed such that the distance in the second direction between the second receiving surface 23 and the developing cartridge 1 is in the direction away from the first side frame 201 in the first direction (ie, from the first increase in the direction from one side frame 201 to the second side frame 202). The second receiving surface 23 is an example of a second inclined surface.

As will be described in detail below, when the separating member 60 of the developing cartridge 1 attached to each tank 2A is moved in the first direction, each of the first receiving surface 22 and the second receiving surface 23 is configured to be opposed to each other The developing cartridge 1 is guided (moved) in the second direction on the frame 200 while the first inclined surface 621 is in contact with the first receiving surface 22 and the second inclined surface 631 is in contact with the second receiving surface 23, respectively.

<1.4. Separation movement of the separation member 60>

Next, the movement of the developing cartridge according to the present embodiment in the image forming apparatus 100 when the image forming apparatus 100 is switched between the contact state and the separation state will be described.

16A and 16B are views for describing the separation movement of the developing cartridge 1 by the separation member 60 . FIG. 16A shows the developing cartridge 1 in the contact state of the image forming apparatus 100 . FIG. 16B shows the developing cartridge 1 in a separated state of the image forming apparatus 100 . 17 is a perspective view of the developing cartridge 1 and the photosensitive drum 21, showing a state in which the developing roller 30 and the photosensitive drum 21 are in contact with each other. 18 is a perspective view of the developing cartridge 1 and the photosensitive drum 21, showing a state in which the developing roller 30 and the photosensitive drum 21 are separated from each other.

When each developing cartridge 1 is attached to the corresponding groove 2A of the drawer 2 , the developing roller 30 of each developing cartridge 1 contacts the corresponding photosensitive drum 21 , as shown in FIG. 17 . That is, the image forming apparatus 100 is in a contact state. In this contact state of the image forming apparatus 100, as shown in FIG. 16A, the first inclined surface 621 of the first cam 62 is in contact with the first receiving surface 22, and the second inclined surface 631 of the second cam 63 is in contact with the second receiving surface 22. Surface 23 contacts. In other words, the first inclined surface 621 and the second inclined surface 631 engage the frame 200 .

More precisely, when the developing cartridge 1 is attached to the drawer 2 , the first inclined surface 621 is not in contact with the first receiving surface 22 , and the second inclined surface 631 is not in contact with the second receiving surface 23 . Then, when the developing cartridge 1 moves a predetermined distance in the first direction, the first inclined surface 621 is brought into contact with the first receiving surface 22 and the second inclined surface 631 is brought into contact with the second receiving surface 23 . Incidentally, when the developing cartridge 1 is attached to the drawer 2 , the first inclined surface 621 may contact the first receiving surface 22 and the second inclined surface 631 may contact the second receiving surface 23 .

The first inclined surface 621 extends radially outward from the shaft 61 in a direction from the first cam 62 toward the second cam 63 in the first direction. The first receiving surface 22 contacts a portion of the first inclined surface 621 . The distance between a part of the first inclined surface 621 and the shaft 61 in the radial direction of the shaft 61 is smaller than the distance between the remaining part of the first inclined surface 621 and the shaft 61 in the radial direction of the shaft 61 . Similarly, the second inclined surface 631 extends radially outward from the shaft 61 in the direction from the first cam 62 toward the second cam 63 in the first direction. The second receiving surface 23 contacts a portion of the second inclined surface 631 . The distance in the radial direction of the shaft 61 between a part of the second inclined surface 631 and the shaft 61 is smaller than the distance in the radial direction of the shaft 61 between the remaining part of the second inclined surface 631 and the shaft 61 .

As described above, each of the first cam 62 and the second cam 63 has a tapered shape. Therefore, even if the shaft 61 is rotated about the second axis, the first inclined surface 621 and the second inclined surface 631 can reliably contact (engage) the first receiving surface 22 and the second receiving surface 23, respectively.

The image forming apparatus 100 includes a drive unit 103 and a pressing member 104 . The driving unit 103 is configured to move the pressing member 104 in the first direction. The drive unit 103 is, for example, a motor. The pressing member 104 has a cylindrical shape or a rectangular cylindrical shape, and extends in the first direction. The pressing member 104 is movable in the first direction between the contact position and the non-contact position by the second concave portion 202A formed in the second side frame 202 to apply the pressing force from the outside of the frame 200 to the second cam 63 . The pressing member 104 in the contact position contacts the second cam 63 of the developing cartridge 1 attached to the slot 2A of the drawer 2 , while the pressing member 104 in the non-contact position does not contact the second cam 63 .

In order to separate the developing roller 30 from the photosensitive drum 21 , the driving unit 103 moves the pressing member 104 toward the direction from the second cam 63 to the first cam 62 in the first direction. Therefore, the second cam 63 is pressed by the pressing member 104 toward the direction from the second cam 63 to the first cam 62 in the first direction. When the second cam 63 receives the pressing force from the pressing member 104 through the second recessed portion 202A, the shaft 61 , the first cam 62 and the second cam 63 are oriented in the first direction relative to the casing 10 and the developing roller 30 from the second The cam 63 moves in the direction of the first cam 62 .

In this case, the first inclined surface 621 of the first cam 62 moves in the first direction toward the direction from the second cam 63 to the first cam 62 while maintaining contact with the first receiving surface 22 . As described above, the first inclined surface 621 is formed to extend radially outward with respect to the shaft 61 in the direction from the first cam 62 to the second cam 63 . Therefore, when the first cam 62 is moved in the first direction toward the direction from the second cam 63 to the first cam 62 , the portion of the first inclined surface 621 that is in contact with the first receiving surface 22 is in the radial direction of the shaft 61 The upper retracts from the shaft 61 . The first inclined surface 621 and the first receiving surface 22 face each other in the second direction. That is, when the first inclined surface 621 moves in the first direction toward the direction from the second cam 63 to the first cam 62 , the first inclined surface 621 also moves toward the direction away from the first receiving surface 22 in the second direction direction shift, as shown in Figure 16B.

Similar to the first inclined surface 621 , the second inclined surface 631 of the second cam 63 moves toward the direction from the second cam 63 to the first cam 62 in the first direction while contacting the second receiving surface 23 . As described above, the second inclined surface 631 is formed such that the second inclined surface 631 extends radially outward with respect to the shaft 61 in the direction from the first cam 62 to the second cam 63 . Therefore, when the second cam 63 is moved in the first direction toward the direction from the second cam 63 to the first cam 62 , the portion of the second inclined surface 631 that is in contact with the second receiving surface 23 is in the radial direction of the shaft 61 away from the shaft 61. The second inclined surface 631 and the second receiving surface 23 face each other in the second direction. That is, when the second inclined surface 631 is moved in the direction from the second cam 63 to the first cam 62 in the first direction, the second inclined surface 631 is also directed in the second direction away from the second receiving surface 23 direction shift, as shown in Figure 16B.

As the first cam 62 and the second cam 63 move in the second direction while moving in the first direction, the shaft 61 also moves in the same manner. When the shaft 61, the first cam 62 and the second cam 63 move in the second direction, the housing 10 and the developing roller 30 also move in the second direction, as shown in FIG. 16B. In other words, in response to the axial movement of the shaft 61 along the second axis, the first cam 62 and the second cam 63 may move together with the housing 10 and the developing roller 30 in a direction not parallel to the second axis. Further in other words, each of the first inclined surface 621 and the second inclined surface 631 provides cam movement in response to axial movement of the shaft 61 along the second axis. As shown in FIG. 18 , this movement causes the developing roller 30 to be separated from the photosensitive drum 21 in the second direction against the urging force of a conventional urging member (not shown) provided in the drawer 2 . Therefore, the image forming apparatus 100 enters the separated state.

The movement of the shaft 61, the first cam 62 and the second cam 63 in the first direction causes expansion and contraction of the coil spring 64 in the first direction. As described above, when the shaft 61 is in the first position, the coil spring 64 has the first length, as shown in FIG. 8 . Conversely, when the shaft 61 is in the second position, the coil spring 64 has a second length that is shorter than the first length, as shown in FIG. 9 . Due to the pressing force of the pressing member 104, the coil spring 64 is compressed from the first length to the second length, and when the pressing force acting on the separation member 60 is released by the pressing member 104, the coil spring 64 extends from the second length to first length.

When the shaft 61 moves back from the second position to the first position together with the first cam 62 and the second cam 63, the portion of the first inclined surface 621 that is in contact with the first receiving surface 22 is in the second position due to the opposite mechanism to the above-mentioned mechanism. The axis 61 is approached in two directions. Similarly, a portion of the second inclined surface 631 that is in contact with the second receiving surface 23 approaches the shaft 61 in the second direction. These movements of the shaft 61, the first cam 62 and the second cam 63 move the housing 10 and the developing roller 30 in the second direction, thereby allowing the developing roller 30 to approach the photosensitive drum 21 in the second direction. As a result, the outer circumferential surface of the developing roller 30 is brought into contact with the outer circumferential surface of the photosensitive drum 21 due to the urging force of the conventional urging member (not shown) provided in the drawer 2 . Therefore, the image forming apparatus 100 enters the contact state.

<1.5. Advantageous Effects of the First Embodiment>

In the present embodiment, the first cam 62 and the second cam 63 are arranged at both ends of the shaft 61 in the first direction, respectively. Compared with the case where only one of the first cam 62 and the second cam 63 is arranged at the shaft 61, this configuration can prevent one of the ends of the casing 10 and the developing roller 30 in the first direction from being damaged in the image forming apparatus. 100 is tilted while being switched between the separation state and the contact state.

As described above, the pressing force directed in the first direction moves the shaft 61 in the first direction relative to the casing 10 and the developing roller 30 . When the first inclined surface 621 contacts the first receiving surface 22 due to the movement of the shaft 61 in the first direction, the first inclined surface 621 moves in the second direction along the first receiving surface 22 . The casing 10 and the developing roller 30 also move in the second direction according to the movement of the first inclined surface 621 in the second direction. With this configuration, the developing cartridge 1 can be moved in the second direction by the driving force directed in the first direction, not by the driving force acting on both ends of the developing cartridge 1 . In addition, the developing cartridge 1 has the first inclined surface 621 and the shaft 61 . Therefore, compared with the case where the drum cartridge includes the shaft, the shaft 61 does not interrupt the attachment of the developing cartridge 1 to the groove 2A and the separation of the developing cartridge 1 from the groove 2A.

Furthermore, when the shaft 61 moves in the first direction, no driving force from both ends of the shaft 61 in the first direction is required. That is, the developing cartridge 1 is movable due to the driving force applied from one end of the shaft 61 in the first direction.

In the present embodiment, the image forming apparatus 100 further includes a drive source arranged on one side of the main frame 101 on which one end of the developing cartridge 1 and the drawer 2 in the first direction is located. The driving source is configured to drive the developing roller 30 and the photosensitive drum 21 to rotate. A drive unit 103 serving as a drive source for moving the pressing member 104 in the first direction may be arranged near the drive source. With this arrangement, the driving sources of the image forming apparatus 100 (ie, the driving unit 103 and the driving sources for driving the developing roller 30 and the photosensitive drum 21 ) can be collectively arranged on one side of the developing cartridge 1 and the drawer 2 . Therefore, size reduction of the image forming apparatus 100 can be achieved. Furthermore, since the parts for moving the developing cartridge 1 do not need to be arranged at both ends of the drawer 2 in the first direction, the configuration of the drawer 2 can be simplified and the size of the drawer 2 can be reduced.

<2. Second Embodiment>

Next, the developing cartridge 1 according to the second embodiment will be described with reference to FIGS. 19 to 20B, wherein the same parts and components are denoted by the same reference numerals as those shown in the first embodiment to avoid repetitive description.

In the first embodiment, each of the first inclined surface 621 and the second inclined surface 631 is inclined at a constant angle with respect to the first direction. In contrast, in the second embodiment, each of the first inclined surface 621 and the second inclined surface 631 has at least two inclined surfaces defining different angles. Hereinafter, the difference between the second embodiment and the first embodiment will be described.

FIG. 19 is a plan view of the developing cartridge 1 according to the second embodiment viewed in the third direction.

The first inclined surface 621 of the first cam 62 has an inclined surface 621A and an inclined surface 621B. The inclined surface 621A and the inclined surface 621B are aligned with each other in the first direction. The inclined surface 621A is positioned farther from the second cam 63 in the first direction than the inclined surface 621B is from the second cam 63 . Further, the inclination of the inclined surface 621A with respect to the first direction is steeper than the inclination of the inclined surface 621B with respect to the first direction. Specifically, the inclined surface 621A is inclined relative to the first direction to define an acute angle between the inclined surface 621A and the first direction; the inclined surface 621B is also inclined relative to the first direction to define an acute angle between the inclined surface 621B and the first direction and the angle between the inclined surface 621A and the first direction is greater than the angle between the inclined surface 621B and the first direction.

The angle between the inclined surface 621A and the first direction is greater than or equal to 43 degrees and less than or equal to 47 degrees. More preferably, the angle between the inclined surface 621A and the first direction is 45 degrees. The angle between the inclined surface 621B and the first direction is greater than or equal to 12 degrees and less than or equal to 17 degrees. Preferably, the angle between the inclined surface 621B and the first direction is greater than or equal to 14 degrees and less than or equal to 15 degrees. More preferably, the angle between the inclined surface 621B and the first direction is 14 degrees or 15 degrees.

The ratio of the length of the inclined surface 621A in the first direction to the length of the inclined surface 621A in the radial direction of the shaft 61 (ie, the second direction) is, for example, 1:1 (one to one). Further, the ratio of the length of the inclined surface 621B in the first direction to the length of the inclined surface 621B in the radial direction (ie, the second direction) of the shaft 61 is, for example, 4:1 (four to one).

The second inclined surface 631 of the second cam 63 has an inclined surface 631A and an inclined surface 631B. The inclined surface 631A and the inclined surface 631B are aligned with each other in the first direction. The inclined surface 631A is positioned to be closer to the first cam 62 (ie, the first inclined surface 621 ) in the first direction than the inclined surface 631B is to the first cam 62 (ie, the first inclined surface 621 ). Furthermore, the inclination of the inclined surface 631A with respect to the first direction is steeper than the inclination of the inclined surface 631B with respect to the first direction. Specifically, the inclined surface 631A is inclined relative to the first direction to define an acute angle between the inclined surface 631A and the first direction; the inclined surface 631B is also inclined relative to the first direction to define an acute angle between the inclined surface 631B and the first direction and the angle between the inclined surface 631A and the first direction is greater than the angle between the inclined surface 631B and the first direction.

The angle between the inclined surface 631A and the first direction is greater than or equal to 43 degrees and less than or equal to 47 degrees. More preferably, the angle between the inclined surface 631A and the first direction is 45 degrees. The angle between the inclined surface 631B and the first direction is greater than or equal to 12 degrees and less than or equal to 17 degrees. Preferably, the angle between the inclined surface 631B and the first direction is greater than or equal to 14 degrees and less than or equal to 15 degrees. More preferably, the angle between the inclined surface 631B and the first direction is 14 degrees or 15 degrees.

The ratio of the length of the inclined surface 631A in the first direction to the length of the inclined surface 631A in the radial direction of the shaft 61 (ie, the second direction) is, for example, 1:1 (one to one). The ratio of the length of the inclined surface 631B in the first direction to the length of the inclined surface 631B in the radial direction of the shaft 61 (ie, the second direction) is, for example, 4:1 (four to one).

Preferably, the inclined surface 621A and the inclined surface 631A are inclined with respect to the first direction so as to define the same angle to each other. In addition, it is also preferable that the inclined surface 621B and the inclined surface 631B are inclined with respect to the first direction so as to define the same angle with each other.

<2.1. Separation movement by separation member 60>

The following will describe the movement of the developing cartridge 1 in the image forming apparatus 100 according to the second embodiment when the image forming apparatus 100 is switched between the contact state and the separation state.

20A and 20B are views for describing the separation movement of the developing cartridge 1 performed by the separation member 60 . FIG. 20A shows the developing cartridge 1 in the contact state of the image forming apparatus 100 . FIG. 20B shows the developing cartridge 1 in a separated state of the image forming apparatus 100 .

In the contact state of the image forming apparatus 100 in which the developing roller 30 of the developing cartridge 1 is in contact with the photosensitive drum 21, the inclined surface 621A of the first inclined surface 621 contacts the first receiving surface 22, and the inclined surface 631A of the second inclined surface 631 contacts The second receiving surface 23 is shown in Fig. 20A.

More specifically, when the developing cartridge 1 is attached to the drawer 2 , the inclined surface 621A is separated from the first receiving surface 22 , and the inclined surface 631A is separated from the second receiving surface 23 . Then, as the developing cartridge 1 moves in the first direction by a predetermined distance, the inclined surface 621A is brought into contact with the first receiving surface 22 , and the inclined surface 631A is brought into contact with the second receiving surface 23 . Incidentally, the inclined surface 621A may contact the first receiving surface 22 , and the inclined surface 631A may contact the second receiving surface 23 when the developing cartridge 1 is attached to the drawer 2 .

When the second cam 63 is pressed toward the first cam 62 by the pressing member 104 in the first direction, the shaft 61 , the first cam 62 and the second cam 63 move in the first direction relative to the housing 10 and the developing roller 30 . At this time, the inclined surface 621A of the first inclined surface 621 moves toward the direction from the second cam 63 to the first cam 62 in the first direction while contacting the first receiving surface 22 . In addition, the inclined surface 631A of the second inclined surface 631 moves toward the direction from the second cam 63 to the first cam 62 in the first direction while contacting the second receiving surface 23 . Therefore, the first inclined surface 621 is also moved in the second direction toward the direction away from the first receiving surface 22, as shown in FIG. 20B. In addition, the second inclined surface 631 also moves in a direction away from the second receiving surface 23 in the second direction, as shown in FIG. 20B . By this movement, the developing roller 30 is separated from the photosensitive drum 21 in the second direction (see FIG. 18 ).

When the shaft 61 , the first cam 62 and the second cam 63 are further moved in the first direction toward the direction from the second cam 63 to the first cam 62 , the inclined surface 621B of the first inclined surface 621 contacts the first receiving surface 22 , to move in the first direction along the first receiving surface 22 toward the direction from the second cam 63 to the first cam 62 . Further, the inclined surface 631B of the second inclined surface 631 contacts the second receiving surface 23 to move in the first direction along the second receiving surface 23 toward the direction from the second cam 63 to the first cam 62 .

When the shaft 61 moves back from the second position to the first position together with the first cam 62 and the second cam 63, the portion of the first inclined surface 621 that is in contact with the first receiving surface 22 is in the second position due to the opposite mechanism to the above-mentioned mechanism. The axis 61 is approached in two directions. Similarly, a portion of the second inclined surface 631 that is in contact with the second receiving surface 23 approaches the shaft 61 in the second direction. Therefore, the casing 10 and the developing roller 30 move in the second direction so that the developing roller 30 approaches the photosensitive drum 21 in the second direction. Therefore, the image forming apparatus 100 enters the contact state.

<2.2. Advantageous Effects of the Second Embodiment>

As described above, the pressing force from the pressing member 104 moves the shaft 61 in the first direction relative to the casing 10 and the developing roller 30 . When the first inclined surface 621 contacts the first receiving surface 22 due to the movement of the shaft 61 in the first direction, the first inclined surface 621 moves in the second direction along the first receiving surface 22 . According to the movement of the first inclined surface 621 in the second direction, the casing 10 and the developing roller 30 also move in the second direction. With this configuration, the developing cartridge 1 can be moved in the second direction by the driving force directed in the first direction, not by the driving force acting on both ends of the developing cartridge 1 . In addition, the developing cartridge 1 has the first inclined surface 621 and the shaft 61 . Therefore, the shaft 61 does not interrupt the attachment of the developing cartridge 1 to the groove 2A and the separation of the developing cartridge 1 from the groove 2A, compared to the case where the drum cartridge includes the shaft.

Furthermore, when the shaft 61 moves in the first direction, no driving force from both ends of the shaft 61 in the first direction is required. That is, the developing cartridge 1 is movable due to the driving force applied from one end of the shaft 61 in the first direction.

Further, in the second embodiment, the image forming apparatus 100 further includes a drive source arranged on one side of the main frame 101 on which one end of the developing cartridge 1 and the drawer 2 in the first direction is located. The driving source is configured to drive the developing roller 30 and the photosensitive drum 21 to rotate. A drive unit 103 serving as a drive source for moving the pressing member 104 in the first direction may be arranged near the drive source. With this arrangement, the driving sources of the image forming apparatus 100 (ie, the driving unit 103 and the driving sources for driving the developing roller 30 and the photosensitive drum 21 ) can be collectively arranged on one side of the developing cartridge 1 and the drawer 2 . Therefore, size reduction of the image forming apparatus 100 can be achieved. Furthermore, since the parts for moving the developing cartridge 1 do not need to be arranged at both ends of the drawer 2 in the first direction, the configuration of the drawer 2 can be simplified and the size of the drawer 2 can be reduced.

The inclined surface 621A of the first inclined surface 621 which first contacts the first receiving surface 22 during the movement of the first cam 62 in the first direction toward the direction from the second cam 63 to the first cam 62 is steeper than the inclined surface 621B. Similarly, the inclined surface 631A of the second inclined surface 631 that first contacts the second receiving surface 23 during the movement of the second cam 63 in the first direction toward the direction from the second cam 63 to the first cam 62 is more inclined than the inclined surface 631B. steep. With this configuration, at the start of the movement of the separation member 60 in the first direction, the amount of movement of the separation member 60 in the second direction can be increased. Therefore, the developing roller 30 can be separated from the photosensitive drum 21 while reducing the amount of movement of the separation member 60 in the first direction.

Further, the inclined surface 621B whose inclination relative to the first direction is smaller than the inclined surface 621A contacts the first receiving surface 22 , and the inclined surface 631B whose inclination relative to the first direction is smaller than the inclined surface 631A contacts the second receiving surface 23 . Therefore, the separation member 60 can move in the first direction with a smaller amount of movement in the second direction. This configuration can reduce the driving load of the pressing member 104 .

<3. Modification example>

Although the detailed description has been made with reference to the embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the above-described embodiments.

In the above-described embodiment, the separation member 60 includes the first cam 62 and the second cam 63 . However, the separation member 60 may include at least one of the first cam 62 and the second cam 63 . In addition, the separation member 60 may include at least one of the first inclined surface 621 and the second inclined surface 631 . In other words, in the case where only the first cam 62 is provided, only the first inclined surface 621 is provided in the separation member 60 . On the other hand, in the case where only the second cam 63 is provided, only the second inclined surface 631 is provided in the separation member 60 . Alternatively, the first inclined surface 621 and the second inclined surface 631 may be formed without providing the first cam 62 and the second cam 63 . For example, the first inclined surface 621 and the second inclined surface 631 may be formed by machining the shaft 61 so that the outer peripheral surface of the end portion of the shaft 61 is inclined with respect to the first direction.

Although the coil spring 64 is used as an example of the elastic member in the above-described embodiment, the elastic member is not limited to the coil spring 64 . For example, a material having elasticity, such as a leaf spring, a torsion spring, rubber, sponge, etc., may be used as the elastic member.

Furthermore, various features appearing in the above-described embodiments and modifications can be appropriately combined while avoiding conflicting combinations.

Claims (15)

1. a kind of image forming apparatus characterized by comprising

Delevoping cartridge, the Delevoping cartridge include the developer roll with external peripheral surface；

Photosensitive drums, the photosensitive drums can be around the rotation axis rotations extended in the axial direction, and the photosensitive drums have outer Circumferential surface；

Drawer, the drawer include frame, the Delevoping cartridge can the developer roll the external peripheral surface towards described The frame is attached in the state of the external peripheral surface of photosensitive drums, the frame is movably supported the Delevoping cartridge, And at least part of the Delevoping cartridge can move on the axial direction, and the frame is configured in response to attached It is connected to described at least part moving on the axial direction of the Delevoping cartridge of the frame and makes the Delevoping cartridge It is moved on detaching direction, the detaching direction is outside the external peripheral surface of the developer roll and the described of the photosensitive drums The direction of circumferential surface separation；

Pressing member, the pressing member have the cylindrical shape extended on the axial direction, and can be in contact position It sets and is moved on the axial direction between non-contacting position, the pressing member in the contact position is shown with described The contact of shadow box, and be configured to press the Delevoping cartridge on the axial direction, so that the Delevoping cartridge is in the axial direction It is moved on direction, the pressing member in the non-contacting position is separated with the Delevoping cartridge；With

Driving unit, the driving unit are constructed such that the pressing member in the contact position and the non-contacting position Between moved on the axial direction.

2. image forming apparatus according to claim 1, which is characterized in that wherein, the drawer includes the photosensitive drums.

3. image forming apparatus according to claim 1 or 2, which is characterized in that wherein, the drawer has opening, institute Stating pressing member can be moved between the contact position and the non-contacting position by the opening.

4. image forming apparatus according to claim 1 or 2, which is characterized in that wherein, the Delevoping cartridge has removable Ground supports to the part of the frame, and

Wherein, the frame is configured to, in response to be attached to the frame the Delevoping cartridge the part described Moving and moving the Delevoping cartridge on the detaching direction on axial direction.

5. image forming apparatus according to claim 1 or 2, which is characterized in that wherein, the frame includes:

First side frame；With

Second side frame, second side frame are spaced apart on the axial direction with first side frame, the development Box can be attached to the frame, institute on the axial direction between first side frame and second side frame Stating the second side frame has the through-hole for running through second side frame on the axial direction, and the through-hole allows to be attached to A part of the Delevoping cartridge of the frame is exposed to the outside of the frame, and the pressing member is allowed to connect described It is therefrom moved between touching position and the non-contacting position.

6. image forming apparatus according to claim 1 or 2, which is characterized in that wherein, the detaching direction and the axis Intersect to direction.

7. image forming apparatus according to claim 1 or 2, which is characterized in that it further comprise main frame, the drawer It can be detachably attached to the main frame.

8. image forming apparatus as claimed in claim 1 or 2, which is characterized in that it further comprise another Delevoping cartridge, it is described Another Delevoping cartridge includes another developer roll,

Wherein, the frame includes another photosensitive drums, and

Wherein, the Delevoping cartridge can be attached to the frame corresponding with the photosensitive drums, another described Delevoping cartridge can It is attached to the frame corresponding with another described photosensitive drums.

9. a kind of image forming apparatus characterized by comprising

Delevoping cartridge, the Delevoping cartridge include the developer roll with external peripheral surface；

Drum box, the bulging box include:

Photosensitive drums, the photosensitive drums can be around the rotation axis rotations extended in the axial direction, and the photosensitive drums have outer Circumferential surface；With

Frame, the Delevoping cartridge can the developer roll the external peripheral surface towards the excircle of the photosensitive drums The frame is attached in the state of surface, the frame is movably supported the Delevoping cartridge, and the Delevoping cartridge is extremely Few a part can move on the axial direction, and the frame is configured in response to being attached to described in the frame Described at least part moving on the axial direction of Delevoping cartridge and move the Delevoping cartridge on detaching direction, institute Stating detaching direction is the direction that the external peripheral surface of the developer roll is separated with the external peripheral surface of the photosensitive drums；

Pressing member, the pressing member have the cylindrical shape extended on the axial direction, and can be in contact position It sets and is moved on the axial direction between non-contacting position, the pressing member in the contact position is shown with described The contact of shadow box, the pressing member in the non-contacting position are separated with the Delevoping cartridge；With

Driving unit, the driving unit are constructed such that the pressing member in the contact position and the non-contacting position Between moved on the axial direction.

10. image forming apparatus according to claim 9, which is characterized in that wherein, the bulging box has opening, described Pressing member can be moved between the contact position and the non-contacting position by the opening.

11. image forming apparatus according to claim 9 or 10, which is characterized in that wherein, the Delevoping cartridge has removable The part of the frame is supported to dynamicly, and

Wherein, the frame is configured to, in response to be attached to the frame the Delevoping cartridge the part described Moving and moving the Delevoping cartridge on the detaching direction on axial direction.

12. image forming apparatus according to claim 9 or 10, which is characterized in that wherein, the frame includes:

First side frame；With

Second side frame, second side frame are spaced apart on the axial direction with first side frame, the development Box can be attached to the frame on the axial direction between first side frame and second side frame, described Second side frame has the through-hole for running through second side frame on the axial direction, and the through-hole allows to be attached to institute The a part for stating the Delevoping cartridge of frame is exposed to the outside of the frame, and allows the pressing member in the contact It is therefrom moved between position and the non-contacting position.

13. image forming apparatus according to claim 9 or 10, which is characterized in that wherein, the detaching direction with it is described Axial direction intersection.

14. image forming apparatus according to claim 9 or 10, which is characterized in that it further comprise main frame, the drum Box can be detachably attached to the main frame.

15. image forming apparatus according to claim 9 or 10, which is characterized in that it further comprise another Delevoping cartridge, Another described Delevoping cartridge includes another developer roll,

Wherein, the bulging box includes another photosensitive drums being arranged in the frame, and

Wherein, the Delevoping cartridge can be attached to the frame corresponding with the photosensitive drums, another described Delevoping cartridge can It is attached to the frame corresponding with another described photosensitive drums.