JP7797945B2 - drum cartridge - Google Patents

Description

This disclosure relates to a drum cartridge.

Electrophotographic image forming devices such as laser printers and LED printers are known. A conventional image forming device is described, for example, in Patent Document 1.

The image forming apparatus disclosed in Patent Document 1 has a developer cartridge and a drum cartridge. The developer cartridge has a developer roller. The drum cartridge has a photosensitive drum. When the developer cartridge is installed in the drum cartridge, the developer roller comes into contact with the photosensitive drum.

The developer cartridge in Patent Document 1 also has a spacing member that is movable relative to the housing of the developer cartridge. When the spacing member is moved while the developer cartridge is attached to the drum cartridge, the spacing member comes into contact with the drum frame of the drum cartridge. This causes the developer cartridge to move relative to the drum frame. As a result, the developer roller can be separated from the photosensitive drum.

Japanese Patent Application Laid-Open No. 2021-113858

In this type of image forming device, when the spacer member of the developer cartridge is moved and brought into contact with the drum frame, the drum frame may bend. This causes the problem that the developer cartridge cannot be moved accurately relative to the drum frame.

The objective of this disclosure is to provide a drum cartridge that can move the developer cartridge with precision relative to the drum frame by suppressing bending of the drum frame during the separation operation.

In order to solve the above-mentioned problems, the first disclosure of the present application provides a drum cartridge to which a developing cartridge having a developing roller can be detachably attached, the drum cartridge comprising: a photosensitive drum rotatable about a drum axis extending in a first direction; a drum frame to which the developing cartridge can be detachably attached, the drum frame comprising: a first side frame located at one end of the drum frame in the first direction; a second side frame located at the other end of the drum frame in the first direction, the second side frame being spaced apart from the first side frame in the first direction; a first metal frame made of metal, the first metal frame attached to the inner surface of the first side frame; and a second metal frame made of metal, the first metal frame being spaced apart from the front The drum frame includes a second metal frame attached to the inner surface of the second side frame, a connecting frame located between the first metal frame and the second metal frame in the first direction and connecting the first metal frame and the second metal frame in the first direction, and a first separation portion located on the connecting frame that moves the developer cartridge relative to the drum frame so that the development roller separates from the photosensitive drum when a portion of the developer cartridge moves in the first direction relative to the drum frame with the developer cartridge attached to the drum frame.

The second disclosure of the present application is the drum cartridge of the first disclosure, characterized in that the connecting frame rotatably supports the photosensitive drum.

The third disclosure of the present application is the drum cartridge described in claim 1 or claim 2, characterized in that the connecting frame has a first end fixed to the first metal frame and a second end located away from the first end in the first direction and fixed to the second metal frame, and the first spaced portion is located at the first end.

The fourth disclosure of the present application is a drum cartridge according to any one of the first to third disclosures, characterized in that it further comprises a second separation portion located on the connecting frame that moves the developing cartridge relative to the drum frame so that the developing roller separates from the photosensitive drum when a part of the developing cartridge moves in the first direction relative to the drum frame while the developing cartridge is attached to the drum frame.

The fifth disclosure of the present application is a drum cartridge according to any one of the first to fourth disclosures, characterized in that the first metal frame is fixed to the connecting frame with bolts.

The sixth disclosure of the present application is the drum cartridge of the fifth disclosure, characterized in that the photosensitive drum is located at one end of the drum frame in a second direction intersecting the first direction, and the bolt is located closer to the first separation portion in the second direction than the photosensitive drum.

The seventh disclosure of the present application is the drum cartridge of the sixth disclosure, wherein the first metal frame has a convex portion that protrudes in the second direction toward the first separation portion, and the convex portion is fixed to the connecting frame by the bolt.

The eighth disclosure of the present application is a developer cartridge according to any one of the first to seventh disclosures, characterized in that the first separation portion is formed integrally with the connecting frame.

The ninth disclosure of the present application is the drum cartridge of the sixth or seventh disclosure, characterized in that the first spaced portion is a rotatable roller.

The tenth disclosure of the present application is the drum cartridge of the ninth disclosure, characterized in that the roller is rotatable about an axis extending in the second direction.

The eleventh disclosure of the present application is the drum cartridge of the ninth disclosure, characterized in that the roller is rotatable about an axis extending in a third direction that intersects the first direction and the second direction.

A twelfth disclosure of the present application is a drum cartridge according to any one of the first to eleventh disclosures, characterized in that the connecting frame is made of resin.

The thirteenth disclosure of the present application is a drum cartridge according to any one of the first to twelfth disclosures, characterized in that the first side frame is made of resin and the second side frame is made of resin.

According to Disclosures 1 to 13 of the present application, the first separation portion is located on the connecting frame. The connecting frame is then connected to the first metal frame and the second metal frame, both of which are made of metal. This makes it possible to suppress bending of the first separation portion. This allows the developer cartridge to be moved accurately relative to the drum frame.

Furthermore, according to the second disclosure of the present application, a first spacing portion is provided on the connecting frame that supports the photosensitive drum. This makes it possible to prevent the first spacing portion from shifting in position relative to the photosensitive drum.

Furthermore, according to the third disclosure of the present application, it is possible to suppress bending of the first and second separation portions. This allows the developer cartridge to be moved more accurately relative to the drum frame.

Furthermore, according to the sixth disclosure of the present application, the first metal frame is fixed to the connecting frame near the first spaced portion. This further suppresses deflection of the first spaced portion.

Furthermore, according to the seventh disclosure of the present application, deflection of the connecting frame near the first separation portion can be further suppressed.

Furthermore, according to the eighth disclosure of this application, the number of parts in the drum cartridge can be reduced.

Furthermore, according to the ninth disclosure of the present application, friction can be reduced when part of the developer cartridge comes into contact with the first separation portion.

Furthermore, according to the eleventh disclosure of the present application, the rollers are arranged along the third direction. This prevents the position of the first separation portion from protruding in the second direction. As a result, deflection of the connecting frame near the first separation portion can be further suppressed.

FIG. 1 is a schematic diagram of an image forming apparatus. FIG. FIG. 2 is a perspective view of a drum cartridge in which four developing cartridges are mounted. FIG. 2 is a perspective view of the drum cartridge without a developing cartridge attached thereto. FIG. 2 is a perspective view of the drum cartridge with the first side frame and the second side frame removed. FIG. 6 is an enlarged view of region A in FIG. 5 . FIG. 2 is a perspective view of four connecting frames and one developing cartridge. FIG. 2 is a perspective view of four connecting frames and one developing cartridge. FIG. 8 is an enlarged view of region B in FIG. 7. FIG. 9 is an enlarged view of region C in FIG. 8 . FIG. 10 is a view of a first separating portion according to a first modified example, viewed in a first direction. FIG. 10 is a view of a first separation portion according to a second modified example, viewed in a first direction.

Embodiments of the present disclosure will be described below with reference to the drawings.

In the following, the direction in which the drum axis of the photosensitive drum extends will be referred to as the "first direction." Furthermore, the direction in which one end of the drum frame where the photosensitive drum is located is aligned with the other end of the drum frame will be referred to as the "second direction." Furthermore, the direction in which the four photosensitive drums are aligned will be referred to as the "third direction."

The first direction and the second direction intersect (preferably perpendicular to) each other. The second direction and the third direction intersect (preferably perpendicular to) each other. The third direction and the first direction intersect (preferably perpendicular to) each other.

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 printer. Specifically, the image forming apparatus 100 is a laser printer or an LED printer. As shown in FIG. 1, the image forming apparatus 100 includes a main body frame 101, a drum cartridge 2, and four developing cartridges 1.

The four developer cartridges 1 are detachable from the drum cartridge 2. Furthermore, the drum cartridge 2 with the four developer cartridges 1 installed is detachable from the main body frame 101.

The four developer cartridges 1 contain developers of different colors (e.g., yellow, magenta, cyan, and black). The developers may be toner, for example. The image forming device 100 prints an image on the surface of printing paper using the developers supplied from the developer cartridges 1.

2. Configuration of the developing cartridge
2 is a perspective view of the developing cartridge 1. As shown in FIG. 2, the developing cartridge 1 includes a housing 10, a developing roller 20, a gear portion 30, and a spacing member 40.

The housing 10 is a container capable of containing developer. The housing 10 has a first outer surface 11 and a second outer surface 12. The first outer surface 11 is located at one end of the housing 10 in the first direction. The second outer surface 12 is located at the other end of the housing 10 in the first direction. The first outer surface 11 and the second outer surface 12 are spaced apart from each other in the first direction.

A storage chamber 13 is provided inside the housing 10. The developer is stored in the storage chamber 13. The housing 10 also has an opening 14. The opening 14 is located at one end of the housing 10 in the second direction. The external space of the housing 10 and the storage chamber 13 are in communication via the opening 14.

The developing roller 20 is a roller that can rotate about a development axis extending in the first direction. The developing roller 20 is located in the opening 14 of the housing 10. In other words, the developing roller 20 is located at one end of the housing 10 in the second direction. The developing roller 20 has a developing roller main body 21 and a developing roller shaft 22. The developing roller main body 21 is a cylindrical member that extends in the first direction. The developing roller main body 21 is made of, for example, elastic rubber. The developing roller shaft 22 is a columnar member that passes through the developing roller main body 21 and extends in the first direction. The developing roller main body 21 is fixed to the developing roller shaft 22. The developing roller shaft 22 is made of metal or conductive resin.

The developing roller 20 rotates about its development axis due to the driving force supplied from the image forming device 100. The developer inside the housing 10 is carried on the outer surface of the developing roller 20.

The gear unit 30 is located on the first outer surface 11 of the housing 10. The gear unit 30 has a gear cover 31, a coupling 32, and multiple gears. The gear cover 31 is fixed to the first outer surface 11 of the housing 10. At least some of the multiple gears are located between the first outer surface 11 and the gear cover 31 in the first direction.

The coupling 32 is exposed from the gear cover 31. When the drum cartridge 2 with the developer cartridge 1 installed is installed in the image forming device 100, the drive shaft of the image forming device 100 is connected to the coupling 32. The rotation of the drive shaft is then transmitted to the developing roller 20 via the coupling 32 and the gear.

As shown in FIG. 2, the housing 10 has a housing groove 15 and a housing hole 16. The gear cover 31 also has a cover hole 33. The housing groove 15 extends in a first direction on the outer surface of the housing 10. The cover hole 33 is located at one end of the housing groove 15 in the first direction. The cover hole 33 penetrates the gear cover 31 in the first direction at a position overlapping with the housing groove 15 in the first direction. The housing hole 16 is located at the other end of the housing groove 15 in the first direction. The housing hole 16 penetrates the housing 10 in the first direction at a position overlapping with the housing groove 15 in the first direction.

When the drum cartridge 2 with four developer cartridges 1 installed is mounted in the image forming device 100, the image forming device 100 can perform a separation operation for each developer cartridge 1. The separation operation is an operation in which the development roller 20 is moved from a contact position where it contacts the photosensitive drum 50 to a separation position where it is separated from the photosensitive drum 50. The image forming device 100 performs the separation operation for the developer cartridge 1 that is not being used out of the four developer cartridges 1. This separates the development roller 20 of the developer cartridge 1 that is not being used from the photosensitive drum 50.

The spacing member 40 is a mechanism for switching the developing roller 20 between the contact position and the separated position described above. The spacing member 40 is located between one end and the other end of the housing 10 in the second direction. As shown in FIG. 2, the spacing member 40 has a first cam 41, a second cam 42, and a shaft 43.

The shaft 43 is disposed in the housing groove 15. The shaft 43 extends in the first direction along the housing groove 15. The shaft 43 is inserted into the cover hole 33 and the housing hole 16. The shaft 43 is, for example, cylindrical. However, the shaft 43 may also be rectangular.

The first cam 41 is located at one end of the shaft 43 in the first direction. The first cam 41 is located on the first outer surface 11 of the housing 10.

The first cam 41 has a first inclined surface 411. The first inclined surface 411 is located on a portion of the circumferential surface of the first cam 41 centered on the shaft 43. The first inclined surface 411 is inclined in the first direction. More specifically, the first inclined surface 411 moves away from the shaft 43 in the radial direction relative to the shaft 43 as it moves away from the other end of the shaft 43 in the first direction. Furthermore, the first inclined surface 411 moves closer to the developing roller 20 as it moves away from the second cam 42 in the first direction.

The second cam 42 is located at the other end of the shaft 43 in the first direction. The second cam 42 is located on the second outer surface 12 of the housing 10.

The second cam 42 has a second inclined surface 421. The second inclined surface 421 is located on a portion of the circumferential surface of the second cam 42 centered on the shaft 43. The second inclined surface 421 is inclined in the first direction. As the second inclined surface 421 moves away from one end of the shaft 43 in the first direction, it approaches the shaft 43 in the radial direction relative to the shaft 43. Furthermore, as the second inclined surface 421 moves away from the first cam 41 in the first direction, it moves away from the developing roller 20.

The spacing member 40 is movable in a first direction between a first position and a second position relative to the housing 10 and the developing roller 20. Movement from the first position to the second position is movement in the direction from the first cam 41 toward the second cam 42.

The developer cartridge 1 also has a spring (not shown). The spring is an elastic member that can expand and contract in a first direction. The spring urges the spacing member 40 in the first direction, from the second position toward the first position. Therefore, when the spacing member 40 is not pressed by the pressing shaft 102 (described below), it is located in the first position.

Details of the spacing operation using the spacing member 40 will be described later.

<3. Drum Cartridge Configuration>
Fig. 3 is a perspective view of the drum cartridge 2 with four developer cartridges 1 attached. Fig. 4 is a perspective view of the drum cartridge 2 with no developer cartridges 1 attached. Fig. 5 is a perspective view of the drum cartridge 2 with a first side frame 61 and a second side frame 62 (described later) removed.

As shown in Figures 3 to 5, the drum cartridge 2 includes four photosensitive drums 50 and a drum frame 60.

The four photosensitive drums 50 are supported by a drum frame 60. The four photosensitive drums 50 are located at one end of the drum frame 60 in the second direction. The four photosensitive drums 50 are arranged at intervals in the third direction. Each photosensitive drum 50 is rotatable about a drum axis extending in the first direction. Each photosensitive drum 50 has a cylindrical outer surface centered on the drum axis. When the developer cartridge 1 is installed in the drum cartridge 2, the outer surface of the developer roller 20 comes into contact with the outer surface of the photosensitive drum 50.

The drum frame 60 is a frame that supports four developer cartridges 1. The four developer cartridges 1 are attached to and detached from the drum frame 60. As shown in Figures 3 to 5, the drum frame 60 has a first side frame 61, a second side frame 62, a first metal frame 63, a second metal frame 64, and four connecting frames 65.

The first side frame 61 is located at one end of the drum frame 60 in the first direction. The first side frame 61 is generally plate-shaped and extends in the second and third directions. The outer surface of the first side frame 61 becomes the outer surface of one end of the drum cartridge 2 in the first direction. The first side frame 61 is made of resin.

The second side frame 62 is located at the other end of the drum frame 60 in the first direction. The second side frame 62 is located away from the first side frame 61 in the first direction. The second side frame 62 is generally plate-shaped and extends along the second and third directions. The outer surface of the second side frame 62 becomes the outer surface of the other end of the drum cartridge 2 in the first direction. The second side frame 62 is made of resin.

The first metal frame 63 is located between the first side frame 61 and the connecting frame 65 (described later) in the first direction. The first metal frame 63 is attached to the inner surface of the first side frame 61. The first metal frame 63 is generally plate-shaped and extends in the second and third directions.

The first metal frame 63 is made of a metal such as iron or stainless steel. The rigidity of the first metal frame 63 is higher than that of the first side frame 61. The rigidity of the first metal frame 63 is also higher than that of the connecting frame 65, which will be described later.

As shown in FIG. 5 , the first metal frame 63 has four first protrusions 631. The four first protrusions 631 are arranged at intervals in the third direction. Each first protrusion 631 protrudes from the first metal frame 63 in the second direction toward a first separation portion 66 (described below).

The second metal frame 64 is located between the second side frame 62 and the connecting frame 65 (described later) in the first direction. The second metal frame 64 is attached to the inner surface of the second side frame 62. The second metal frame 64 is generally plate-shaped and extends along the second and third directions.

The second metal frame 64 is made of a metal such as iron or stainless steel. The rigidity of the second metal frame 64 is higher than that of the second side frame 62. The rigidity of the second metal frame 64 is also higher than that of the connecting frame 65, which will be described later.

As shown in FIG. 5 , the second metal frame 64 has four second protrusions 641. The four second protrusions 641 are arranged at intervals in the third direction. Each second protrusion 641 protrudes from the second metal frame 64 in the second direction toward a second separation portion 67 (described below).

The four photosensitive drums 50 are positioned between the first metal frame 63 and the second metal frame 64 in the first direction. Furthermore, when the developer cartridge 1 is attached to the drum cartridge 2, the housing 10 of the developer cartridge 1 is positioned between the first metal frame 63 and the second metal frame 64 in the first direction.

The four connecting frames 65 are positioned between the first metal frame 63 and the second metal frame 64 in the first direction. The four connecting frames 65 connect the first metal frame 63 and the second metal frame 64 in the first direction. Each of the four connecting frames 65 rotatably supports the photosensitive drum 50. Each connecting frame 65 is made of resin.

The four connecting frames 65 are arranged in the third direction. Each photosensitive drum 50 is located between adjacent connecting frames 65 in the second direction.

Each connecting frame 65 extends in a first direction. Each connecting frame 65 has a first end 651 and a second end 652. The first end 651 is located at one end of the connecting frame 65 in the first direction. The second end 652 is located at the other end of the connecting frame 65 in the first direction. The second end 652 is located away from the first end 651 in the first direction.

The first end 651 of each connecting frame 65 is fixed to the first metal frame 63. The second end 652 of each connecting frame 65 is fixed to the second metal frame 64. Therefore, the four connecting frames 65 are positioned relative to each other by the first metal frame 63 and the second metal frame 64.

Figure 6 is an enlarged view of area A in Figure 5. As shown in Figure 6, the first end 651 of the connecting frame 65 is fixed to the first metal frame 63 with a first bolt 653. Specifically, the first end 651 of the connecting frame 65 is fixed to the first protrusion 631 of the first metal frame 63 with the first bolt 653.

More specifically, the first end 651 of the connecting frame 65 has a first screw hole (not shown) extending in the first direction. Furthermore, the first protrusion 631 of the first metal frame 63 has a first through-hole 632 that penetrates in the first direction. The first bolt 653 is inserted into the first through-hole 632 and fastened to the first screw hole. This sandwiches the first protrusion 631 between the head of the first bolt 653 and the connecting frame 65. As a result, the connecting frame 65 is fixed to the first metal frame 63.

Similarly, the second end 652 of the connecting frame 65 is fixed to the second metal frame 64 with a second bolt (not shown). Specifically, the second end 652 of the connecting frame 65 is fixed to the second protrusion 641 of the second metal frame 64 with the second bolt.

More specifically, the second end 652 of the connecting frame 65 has a second screw hole (not shown) extending in the first direction. Furthermore, the second protrusion 641 of the second metal frame 64 has a second through-hole (not shown) penetrating in the first direction. A second bolt is inserted into the second through-hole and fastened to the second screw hole. This sandwiches the second protrusion 641 between the head of the second bolt and the connecting frame 65. As a result, the connecting frame 65 is fixed to the second metal frame 64.

Figures 7 and 8 are perspective views of four connecting frames 65 and one developer cartridge 1. Figure 7 shows the state when the separation operation is not being performed. Figure 8 shows the state when the separation operation is being performed.

Figure 9 is an enlarged view of area B in Figure 7. As shown in Figure 9, the drum frame 60 further has a first separation portion 66. The first separation portion 66 is located at the first end 651 of the connecting frame 65. The first separation portion 66 is the portion that comes into contact with the first cam 41 of the developer cartridge 1 during the separation operation.

In this embodiment, the first separation portion 66 is formed integrally with the connecting frame 65. That is, the first separation portion 66 in this embodiment is part of the outer surface of the connecting frame 65. The first separation portion 66 has a corner that can come into contact with the first cam 41. In this way, by forming the first separation portion 66 integrally with the connecting frame 65, the number of parts in the drum cartridge 2 can be reduced compared to when the first separation portion 66 is a separate part from the connecting frame 65.

Figure 10 is an enlarged view of area C in Figure 8. As shown in Figure 10, the drum frame 60 further has a second separation portion 67. The second separation portion 67 is located at the second end 652 of the connecting frame 65. The second separation portion 67 is the portion that comes into contact with the second cam 42 of the developer cartridge 1 when the separation operation is performed.

In this embodiment, the second separation portion 67 is formed integrally with the connecting frame 65. That is, the second separation portion 67 in this embodiment is part of the outer surface of the connecting frame 65. The second separation portion 67 has a corner that can contact the second cam 42. In this way, by forming the second separation portion 67 integrally with the connecting frame 65, the number of parts in the drum cartridge 2 can be reduced compared to when the second separation portion 67 is a separate part from the connecting frame 65.

<4. Separation Operation>
Next, the separation operation of the image forming apparatus 100 will be described.

The image forming apparatus 100 has a pressure mechanism (not shown). When the drum cartridge 2 with the developer cartridge 1 installed is mounted in the main body frame 101, the pressure mechanism presses the developer roller 20 toward the photosensitive drum 50. This causes the outer surface of the developer roller 20 to come into contact with the outer surface of the photosensitive drum 50. In other words, the position of the developer roller 20 is the contact position described above.

As shown in Figure 9, the image forming apparatus 100 also has a pressing shaft 102. When the drum cartridge 2, to which four developer cartridges 1 are attached, is mounted in the main body frame 101, the pressing shaft 102 faces the first cam 41 of the developer cartridge 1 in the first direction.

The pressing shaft 102 is movable in a first direction between a retracted position and a protruding position that is closer to the developer cartridge 1 than the retracted position. When performing a spacing operation, the image forming apparatus 100 moves the pressing shaft 102 from the retracted position to the protruding position. This causes the pressing shaft 102 to contact the first cam 41. The pressing shaft 102 then presses the spacing member 40 in the first direction, from the first cam 41 toward the second cam 42. This causes the spring described above to compress, moving the spacing member 40 in the first direction from the first position to the second position relative to the housing 10. In other words, the spacing member 40 moves in the first direction from the first position to the second position relative to the drum frame 60.

When the spacing member 40 moves from the first position to the second position, the first inclined surface 411 of the first cam 41 moves in the first direction while contacting the first spacing portion 66 of the drum cartridge 2. At this time, the first cam 41 moves in a direction away from the photosensitive drum 50 relative to the drum frame 60 due to the resistance force received from the first spacing portion 66.

Similarly, when the spacing member 40 moves from the first position to the second position, the second inclined surface 421 of the second cam 42 moves in the first direction while contacting the second spacing portion 67 of the drum cartridge 2. At this time, the second cam 42 moves in a direction away from the photosensitive drum 50 relative to the drum frame 60 due to the resistance force received from the second spacing portion 67.

As a result, the housing 10 and the developing roller 20, together with the spacing member 40, move relative to the drum frame 60 in a direction away from the photosensitive drum 50. As a result, the developing roller 20 moves from a contact position where it contacts the photosensitive drum 50 to a separation position where it is separated from the photosensitive drum 50.

If the first separation portion 66 were to bend due to the pressing force from the first cam 41 during the above-described separation operation, it would be difficult to move the first cam 41 accurately in a direction away from the photosensitive drum 50. However, in the drum cartridge 2 of this embodiment, the first separation portion 66 is located on the connecting frame 65. The connecting frame 65 is connected to the first metal frame 63 and the second metal frame 64, which are made of metal. This prevents the first separation portion 66 from bending. Therefore, the first cam 41 can be moved accurately in a direction away from the photosensitive drum 50.

Furthermore, if the second spacing portion 67 were to bend due to the pressing force from the second cam 42 during the above-described spacing operation, it would be difficult to move the second cam 42 accurately in a direction away from the photosensitive drum 50. However, in the drum cartridge 2 of this embodiment, the second spacing portion 67 is located on the connecting frame 65. The connecting frame 65 is connected to the first metal frame 63 and the second metal frame 64, which are made of metal. This prevents the second spacing portion 67 from bending. Therefore, the second cam 42 can be moved accurately in a direction away from the photosensitive drum 50.

In addition, in this embodiment, the connecting frame 65 supports the photosensitive drum 50, and the first separation portion 66 is provided on the connecting frame 65. This prevents the first separation portion 66 from shifting out of position relative to the photosensitive drum 50. Therefore, the developing cartridge 1 can be moved more accurately relative to the photosensitive drum 50.

In addition, in this embodiment, the connecting frame 65 supports the photosensitive drum 50, and the second separation portion 67 is provided on the connecting frame 65. This prevents the second separation portion 67 from shifting out of position relative to the photosensitive drum 50. Therefore, the developing cartridge 1 can be moved more accurately relative to the photosensitive drum 50.

In addition, in this embodiment, the first bolt 653 is located closer to the first separation portion 66 in the second direction than the photosensitive drum 50. Specifically, the first end 651 of the connecting frame 65 is fixed to the first protrusion 631 of the first metal frame 63 by the first bolt 653. In this way, by positioning the first bolt 653 near the first separation portion 66, the first metal frame 63 can be fixed to the connecting frame 65 near the first separation portion 66. This further reduces deflection of the first separation portion 66.

Furthermore, in this embodiment, the second bolt is located closer to the second separation portion 67 in the second direction than the photosensitive drum 50. Specifically, the second end 652 of the connecting frame 65 is fixed to the second protrusion 641 of the second metal frame 64 by the second bolt. In this way, by positioning the second bolt near the second separation portion 67, the second metal frame 64 can be fixed to the connecting frame 65 near the second separation portion 67. This further reduces deflection of the second separation portion 67.

5. Modified Examples
Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments.

<5-1. First Modified Example>
In the above embodiment, the first spacing portion 66 and the second spacing portion 67 are formed integrally with the connecting frame 65. However, the first spacing portion 66 and the second spacing portion 67 may be separate components from the connecting frame 65. For example, the first spacing portion 66 and the second spacing portion 67 may be rotatable rollers.

Figure 11 is a view of the first spacing portion 66 according to the first modified example, viewed in the first direction. The first spacing portion 66 in Figure 11 is a rotatable roller. The first spacing portion 66 is located on the connecting frame 65. The first spacing portion 66 is rotatable about an axis extending in the second direction. When the spacing member 40 moves from the first position to the second position, the first inclined surface 411 of the first cam 41 moves in the first direction while contacting the outer peripheral surface of the roller of the first spacing portion 66. At this time, the roller of the first spacing portion 66 rotates. This allows the first cam 41 to move while reducing friction between the first cam 41 and the first spacing portion 66.

In the example shown in Figure 11, during the separation operation, the first cam 41 moves in the third direction relative to the first separation portion 66. Therefore, the developing roller 20 moves in the third direction away from the photosensitive drum 50.

Like the first separation portion 66 in Figure 11, the second separation portion 67 may also be a roller that can rotate about an axis extending in the second direction.

<5-2. Second Modified Example>
FIG. 12 is a view of the first spacing portion 66 according to the second modified example, viewed in the first direction. The first spacing portion 66 in FIG. 12 is a rotatable roller. The first spacing portion 66 is located on the connecting frame 65. The first spacing portion 66 is rotatable about an axis extending in the third direction. When the spacing member 40 moves from the first position to the second position, the first inclined surface 411 of the first cam 41 moves in the first direction while contacting the outer circumferential surface of the roller of the first spacing portion 66. At this time, the roller of the first spacing portion 66 rotates. This allows the first cam 41 to move while reducing friction between the first cam 41 and the first spacing portion 66.

In the example shown in Figure 12, during the separation operation, the first cam 41 moves in the second direction relative to the first separation portion 66. Therefore, the developing roller 20 moves in the second direction away from the photosensitive drum 50.

Furthermore, by arranging the first spacing portion 66 along the third direction as shown in Figure 12, the position of the first spacing portion 66 can be prevented from protruding in the second direction compared to when the first spacing portion 66 is arranged along the second direction as shown in Figure 11. This further prevents the connecting frame 65 from bending near the first spacing portion 66 due to the pressing force received from the first cam 41.

Like the first separation portion 66 in Figure 12, the second separation portion 67 may also be a roller that can rotate about an axis extending in the third direction.

<5-3. Other Modifications>
In the above embodiment, the spacing member 40 has the first cam 41 and the second cam 42. However, the spacing member 40 does not have to have the second cam 42. Also, in the above embodiment, the drum frame 60 has the first spacing portion 66 and the second spacing portion 67. However, the drum frame 60 does not have to have the second spacing portion 67.

Furthermore, in the above embodiment, the spacing member 40, which is part of the developer cartridge 1, is moved in the first direction during the separating operation. However, the part that moves during the separating operation of the developer cartridge 1 does not necessarily have to be the spacing member 40 as in the above embodiment. It is sufficient that a part of the developer cartridge 1 moves in the first direction relative to the drum frame 60, coming into contact with the first spacing portion 66 of the drum frame 60, thereby moving the developer cartridge 1 relative to the drum frame 60 in a direction away from the photosensitive drum 50.

In the above embodiment, four developer cartridges 1 could be attached to one drum cartridge 2. However, the number of developer cartridges 1 attached to a drum cartridge 2 may be one to three, or five or more.

Furthermore, the elements appearing in the above embodiments and variations may be combined as appropriate to the extent that no contradictions arise.

REFERENCE SIGNS LIST 1 Developer cartridge 2 Drum cartridge 10 Housing 20 Developer roller 30 Gear portion 40 Spacer member 50 Photosensitive drum 60 Drum frame 61 First side frame 62 Second side frame 63 First metal frame 64 Second metal frame 65 Connecting frame 66 First spacer portion 67 Second spacer portion 100 Image forming device 631 First protrusion 641 Second protrusion 651 First end portion 652 Second end portion 653 First bolt

Claims (13)

A drum cartridge in which a developing cartridge having a developing roller is detachably mounted,
a photosensitive drum rotatable about a drum axis extending in a first direction;
A drum frame to which the developing cartridge is detachably attached,
a first side frame located at one end of the drum frame in the first direction;
a second side frame located at the other end of the drum frame in the first direction and spaced apart from the first side frame in the first direction;
a first metal frame made of metal and attached to an inner surface of the first side frame;
a second metal frame made of metal and attached to an inner surface of the second side frame;
a connecting frame located between the first metal frame and the second metal frame in the first direction, the connecting frame connecting the first metal frame and the second metal frame in the first direction;
a first separating portion that moves the developer cartridge relative to the drum frame so that the developing roller separates from the photosensitive drum when a portion of the developer cartridge moves in the first direction relative to the drum frame with the developer cartridge attached to the drum frame, the first separating portion being located on the connecting frame;
a drum frame having
A drum cartridge comprising: 2. The drum cartridge according to claim 1,
The drum cartridge is characterized in that the connecting frame rotatably supports the photosensitive drum. 3. The drum cartridge according to claim 1,
The connecting frame is
a first end portion fixed to the first metal frame;
a second end portion located away from the first end portion in the first direction and fixed to the second metal frame;
and
The drum cartridge, wherein the first spaced portion is located at the first end portion. 3. The drum cartridge according to claim 1,
A drum cartridge characterized in that it further comprises a second separation portion located on the connecting frame, which moves the developer cartridge relative to the drum frame so that the developer roller separates from the photosensitive drum when a portion of the developer cartridge moves in the first direction relative to the drum frame while the developer cartridge is attached to the drum frame. 3. The drum cartridge according to claim 1,
The drum cartridge according to claim 1, wherein the first metal frame is fixed to the connecting frame with bolts. 6. The drum cartridge according to claim 5,
the photosensitive drum is located at one end of the drum frame in a second direction intersecting the first direction,
The drum cartridge, wherein the bolt is located closer to the first spaced portion than the photosensitive drum in the second direction. 7. The drum cartridge according to claim 6,
The first metal frame is
a protrusion that protrudes in a direction approaching the first spaced portion in the second direction,
The drum cartridge is characterized in that the protrusion is fixed to the connecting frame by the bolt. 3. The drum cartridge according to claim 1,
The drum cartridge according to claim 1, wherein the first spaced portion is integrally formed with the connecting frame. 7. The drum cartridge according to claim 6,
The drum cartridge is characterized in that the first spaced portion is a rotatable roller. 10. The drum cartridge according to claim 9,
The drum cartridge, wherein the roller is rotatable about an axis extending in the second direction. 10. The drum cartridge according to claim 9,
The drum cartridge is characterized in that the roller is rotatable about an axis extending in a third direction intersecting the first direction and the second direction. 3. The drum cartridge according to claim 1,
The drum cartridge is characterized in that the connecting frame is made of resin. 3. The drum cartridge according to claim 1,
the first side frame is made of resin,
The drum cartridge is characterized in that the second side frame is made of resin.