JP2023080214A - Image forming apparatus - Google Patents

Abstract

To prevent interference between a development cartridge and a drum cartridge.SOLUTION: An image forming apparatus 1 includes a drum cartridge 40, a development cartridge 50, a body housing 2, a cover 2A, a first inside surface 21A, and a second inside surface 22A. The body housing 2 allows the drum cartridge 40 and the development cartridge 50 to be attached/detached in an axial direction. The second inside surface 22A is farther from the cover 2A than the first inside surface 21A. A development housing 52 includes: a first contact surface 53B which comes into contact with the first inside surface 21A when the development cartridge 50 is mounted with the drum cartridge 40 mounted thereon; and a second contact surface 54B which comes into contact with the second inside surface 22A when the development cartridge 50 is mounted on the slot 20 with the drum cartridge 40 mounted on the slot 20. A first contact position between the first inside surface 21A and the first contact surface 53B is farther from a developing roller 51 than a second contact position between the second inside surface 22A and the second contact surface 54B.SELECTED DRAWING: Figure 4

Description

The present disclosure relates to an image forming apparatus having a detachable drum cartridge and developer cartridge.

Conventionally, there has been known an image forming apparatus in which a drum cartridge and a developing cartridge can be attached to and detached from a main housing in the axial direction of a photoreceptor drum (see Patent Document 1). In this technology, the drum cartridge and the developer cartridge are individually attachable and detachable to and from the main housing. In this image forming apparatus, after the drum cartridge and the developing cartridge are mounted, the developing roller is pressed against the photosensitive drum.

JP 2017-173805 A

However, in the prior art, for example, when the developing cartridge is attached while the drum cartridge is attached to the main housing, the developing cartridge and the drum cartridge are separated in the process of attaching the developing cartridge to the main housing. may interfere.

Accordingly, the present disclosure provides an image forming apparatus including a drum cartridge and a developing cartridge that are separately detachable in the axial direction, in which the developing cartridge is axially mounted in a state in which the drum cartridge is attached to a main housing of the image forming apparatus. An object of the present invention is to suppress interference between a developing cartridge and a drum cartridge when they are mounted.

To solve the above problems, an image forming apparatus of the present invention includes a drum cartridge, a developing cartridge, a main housing, a cover, a first inner surface, and a second inner surface. The drum cartridge has a photoreceptor drum rotatable about a first axially extending axis. The developer cartridge has a developer roller rotatable about a second axis extending in the axial direction, and a developer housing capable of accommodating toner. The body housing has a slot extending in the axial direction, and the slot allows the drum cartridge to be attached/detached in the axial direction and the developer cartridge to be attached/detached in the axial direction. do. The cover has a closed state that closes the slot and an open state that opens the slot. The first interior surface is located inside the slot. The second inner surface is located inside the slot and axially further from the cover than the first inner surface. The development housing further includes a first contact surface that contacts the first inner surface when the development cartridge is mounted in the slot in a state in which the drum cartridge is mounted in the slot, and a contact surface that contacts the first inner surface when the development cartridge is mounted in the slot. a second contact surface that contacts the second inner surface when the developer cartridge is installed in the slot in a state. A first contact position between the first inner surface and the first contact surface is further away from the developing roller than a second contact position between the second inner surface and the second contact surface. The image forming apparatus further includes a pressing member that presses the developing roller against the photosensitive drum in a state in which the first inner surface is in contact with the first contact surface and the second inner surface is in contact with the second contact surface. .

According to this configuration, in the image forming apparatus provided with the separately detachable drum cartridge and developing cartridge, the developing roller can be pressed against the photosensitive drum with a simple configuration.

In the above-described configuration, the image forming apparatus further includes an intermediate transfer belt positioned above the drum cartridge and the developing cartridge when the drum cartridge and the developing cartridge are mounted in the main housing. may be provided with an intermediate transfer belt with which the surface of the photoreceptor drum comes into contact when the is attached to the main housing.

In the above-described configuration, the image forming apparatus may further include a discharge section positioned above the intermediate transfer belt for discharging the recording sheet.

In the above-described configuration, the first inner surface may be located further from the photosensitive drum than the second inner surface when the drum cartridge is attached to the main housing.

In the configuration described above, the first contact surface may be located farther from the developing roller than the second contact surface.

In the above-described configuration, the second contact surface may not come into contact with the first inner surface when the developing cartridge is attached to the slot while the drum cartridge is attached to the main housing.

According to this, it is easy to mount the developing cartridge in the slot.

In the configuration described above, the first inner surface may be positioned at the tip of the first projecting portion that projects from the slot, and the second internal surface may be positioned at the tip of the second projecting portion that projects from the slot.

In the above configuration, the pressing member includes a first pressing member and a second pressing member, the first contact surface being located at the tip of the first pressing member, and the second contact surface being the second pressing member. It may be configured to be located at the tip of the.

In the configuration described above, the pressing member includes a first pressing member and a second pressing member, the first inner surface being located at the tip of the first pressing member, and the second inner surface being the second pressing member. It may be configured to be located at the tip of the.

In the above configuration, the first contact surface is positioned at the tip of the first projecting portion that projects from the developing housing, and the second contact surface is positioned at the tip of the second projecting portion that projects from the developing housing. good too.

In the above-described configuration, the main body housing has a first inclined surface located on one side of the first inner surface in the axial direction, and the first inclined surface has the drum cartridge and the developing cartridge attached to the main body housing. In this state, it may extend away from the developing roller as it approaches the cover from the first inner surface.

According to this, since the first inclined surface guides the first contact surface to the first inner surface, it is possible to easily mount the developing cartridge.

In the above-described configuration, the main housing has a second inclined surface located on one side of the second inner surface in the axial direction, and the second inclined surface is provided with the drum cartridge and the developing cartridge attached to the main housing. In this state, it may extend away from the developing roller as it approaches the cover from the second contact surface.

According to this, since the second inclined surface guides the second contact surface to the second inner surface, it is possible to easily mount the developing cartridge.

In the configuration described above, the slot has a guide portion for guiding the developing cartridge when the developing cartridge is installed, and the guiding portion regulates the developing roller so that it does not come into contact with the photosensitive drum when the developing cartridge is installed or removed. Alternatively, the developing roller may contact the photosensitive drum when the developing cartridge is installed in the slot.

According to the present disclosure, interference between the developing cartridge and the drum cartridge can be suppressed when the developing cartridge is attached in the axial direction while the drum cartridge is attached to the main housing of the image forming apparatus. .

1 is a diagram showing a schematic configuration of an image forming apparatus according to a first embodiment of the present disclosure; FIG. It is a figure when mounting a drum cartridge and a development cartridge in a slot. It is the perspective view which looked at the slot, the drum cartridge, and developer cartridge from the top. FIG. 5 is a diagram illustrating a mechanism for pressing the developing roller against the photosensitive drum; It is the perspective view which looked at the slot, the drum cartridge, and developer cartridge from the bottom. 10A to 10D are diagrams (a) to (d) for explaining the action when the developing cartridge is mounted in the slot; FIG. FIG. 10 is a perspective view of slots, a drum cartridge, and a developer cartridge according to a second embodiment; FIG. 11 is a perspective view of slots, a drum cartridge, and a developing cartridge according to a third embodiment; FIG. 11 is a perspective view of slots, a drum cartridge, and a developing cartridge according to a fourth embodiment; It is a figure showing the 1st slope and the 2nd slope concerning the 1st modification. It is a slot, a drum cartridge and a developing cartridge according to the second modified example (a) and the third modified example (b). It is a slot, a drum cartridge, and a developing cartridge according to a fourth modified example (c) and a fifth modified example (d).

Next, the first embodiment of the present disclosure will be described in detail with reference to the drawings as appropriate.
As shown in FIG. 1, the image forming apparatus 1 is a color printer. The image forming apparatus 1 includes a main housing 2 , a supply section 3 , an image forming section 4 and a discharge roller 9 . The supply section 3 supplies the recording sheet S to the image forming section 4 . The image forming section 4 forms an image on the recording sheet S. FIG. A discharge roller 9 discharges the recording sheet S. FIG.

The body housing 2 has an ejection section 2E at the top. The recording sheet S is discharged to the discharge section 2E. The discharge section 2E is positioned above an intermediate transfer belt 63, which will be described later.

The supply unit 3 is located in the lower part inside the main body housing 2 . The supply unit 3 includes a supply tray 31 and a supply mechanism 32 . The supply tray 31 is detachable from the main housing 2 . The supply mechanism 32 conveys the recording sheet S from the supply tray 31 to the image forming section 4 .

The image forming section 4 includes a drum cartridge 40 , a developing cartridge 50 , an exposure device SU, a transfer unit 60 and a fixing unit 70 . A plurality of drum cartridges 40 and developer cartridges 50 are arranged corresponding to the number of toner colors. In this embodiment, four drum cartridges 40 and four developer cartridges 50 are arranged side by side.

Each drum cartridge 40 has a photosensitive drum 41, a frame 42, and a charger (not shown). The photoreceptor drum 41 is rotatable about a first axis X1 extending in the axial direction. The four photoreceptor drums 41 are arranged in an orthogonal direction (simply referred to as "perpendicular direction" in the following description) orthogonal to the axial direction and the vertical direction. The frame 42 rotatably supports the photosensitive drum 41 . Each drum cartridge 40 is independently removable from the main housing 2 in the axial direction.

When the drum cartridge 40 and the developing cartridge 50 are attached to the main body housing 2, the drum cartridge 40 is aligned with the developing cartridge 50 in the orthogonal direction. In this embodiment, the drum cartridge 40 is positioned on one side (the right side in FIG. 1) of the developer cartridge 50 in the orthogonal direction. The developer cartridge 50 is positioned on the other side (the left side in FIG. 1) of the drum cartridge 40 in the orthogonal direction.

Each developer cartridge 50 contains toner of a different color. Each developing cartridge 50 has a developing roller 51 and a developing housing 52 . The developing roller 51 is rotatable about a second axis X2 extending in the axial direction. The development housing 52 can accommodate toner. The four developing rollers 51 are arranged in the orthogonal direction. The developing cartridges 50 are independently attachable to and detachable from the body housing 2 in the axial direction.

An exposure unit SU is positioned below each drum cartridge 40 . The exposure unit SU emits a laser beam (not shown) to each photosensitive drum 41 .

The transfer unit 60 is positioned between the four photosensitive drums 41 and the discharge section 2E. The transfer unit 60 includes a drive roller 61 , a driven roller 62 , an intermediate transfer belt 63 , four primary transfer rollers 64 and secondary transfer rollers 65 .

The intermediate transfer belt 63 is an endless belt. The intermediate transfer belt 63 is positioned above the drum cartridge 40 and the developing cartridge 50 when the drum cartridge 40 and the developing cartridge 50 are attached to the main housing 2 . The surface of the photosensitive drum 41 contacts the intermediate transfer belt 63 when the drum cartridge 40 and the developing cartridge 50 are attached to the main housing 2 . The intermediate transfer belt 63 is stretched between the driving roller 61 and the driven roller 62 .

The primary transfer roller 64 is positioned inside the intermediate transfer belt 63 . The primary transfer roller 64 sandwiches the intermediate transfer belt 63 with the photosensitive drum 41 .

The secondary transfer roller 65 is positioned outside the intermediate transfer belt 63 . The secondary transfer roller 65 sandwiches the intermediate transfer belt 63 with the driving roller 61 .

The fixing unit 70 is positioned above the intermediate transfer belt 63 . The fixing unit 70 has a heating roller 71 and a pressure roller 72 . The pressure roller 72 is pressed against the heating roller 71 .

In the image forming section 4, first, the surface of the photosensitive drum 41 is charged by a charger. After that, the exposure unit SU exposes the surface of the photosensitive drum 41 . Thereby, an electrostatic latent image is formed on the photosensitive drum 41 .

Developing roller 51 then supplies toner to the electrostatic latent image on photoreceptor drum 41 . Thereby, a toner image is formed on the photosensitive drum 41 . Then, the toner image on the photosensitive drum 41 is transferred onto the intermediate transfer belt 63 .

The toner image on the intermediate transfer belt 63 is transferred onto the recording sheet S when the recording sheet S passes between the intermediate transfer belt 63 and the secondary transfer roller 65 . After that, the toner image on the recording sheet S is fixed by the fixing unit 70 . Next, the recording sheet S is discharged by the discharge roller 9 to the discharge section 2E.

As shown in FIG. 2, the main housing 2 has a cover 2A and slots 20. As shown in FIG.

The cover 2A is provided at one end of the main housing 2 in the axial direction. The cover 2A can be opened and closed. The cover 2A has a closed state in which the slot 20 is closed and an open state in which the slot 20 is opened.

A slot 20 is provided corresponding to each drum cartridge 40 and each developer cartridge 50 . Each slot 20 extends axially. Each slot 20 is open on one side in the axial direction. Each slot 20 allows the drum cartridge 40 to be attached/detached in the axial direction and allows the developer cartridge 50 to be attached/detached in the axial direction. One drum cartridge 40 and one developer cartridge 50 can be installed in each slot 20 .

As shown in FIG. 3, each slot 20 has a first wall 20A, a second wall 20B and a third wall 20C. The first wall 20A extends axially and vertically. The second wall 20B faces the first wall 20A and is positioned at a predetermined distance in the orthogonal direction from the first wall 20A. The second wall 20B extends axially and vertically. The third wall 20C connects one end of the first wall 20A and one end of the second wall 20B.

The second wall 20B has a first protrusion 21 and a second protrusion 22 . The first protrusion 21 and the second protrusion 22 are located inside the slot 20 . The first protrusion 21 protrudes from the second wall 20B. The second protrusion 22 protrudes from the second wall 20B. The first projecting portion 21 is positioned at one end in the axial direction. The second protruding portion 22 is positioned at the end on the other side in the axial direction. That is, the second projecting portion 22 is located further away from the cover 2A in the axial direction than the first projecting portion 21 (see FIG. 2).

As shown in FIG. 4, the first projecting portion 21 has a first inner surface 21A and a first inclined surface 21B. The first inner surface 21A and the first inclined surface 21B are positioned inside the slot 20 .
The first inner surface 21A protrudes from the inner surface of the slot 20 . The first inner surface 21A is located at the tip of the first projecting portion 21 . The first inclined surface 21B is located on one side of the first inner surface 21A in the axial direction. The first inclined surface 21B extends away from the developing roller 51 as the cover 2A is approached from the first inner surface 21A when the drum cartridge 40 and the developing cartridge 50 are attached to the main body housing 2 .

The second projecting portion 22 has a second inner surface 22A and a second inclined surface 22B. The second inner surface 22A and the second inclined surface 22B are located inside the slot 20 . The second inner surface 22A protrudes from the inner surface of the slot 20. As shown in FIG. The second inner surface 22A is located at the tip of the second projecting portion 22 . The second inner surface 22A is located further from the cover 2A in the axial direction than the first inner surface 21A (see FIG. 2). The second inclined surface 22B is located on one side of the second inner surface 22A in the axial direction. The second inclined surface 22B extends away from the developing roller 51 toward the cover 2A from the second inner surface 22A when the drum cartridge 40 and the developing cartridge 50 are attached to the main housing 2 .

In this embodiment, the first inclined surface 21B and the second inclined surface 22B have the same inclination angle.

As shown in FIG. 4, when the drum cartridge 40 is attached to the main housing 2, the distance L3 from the first inner surface 21A to the photosensitive drum 41 is the distance from the second inner surface 22A to the photosensitive drum 41. greater than the distance L4. That is, when the drum cartridge 40 is attached to the main housing 2, the first inner surface 21A is located farther from the photosensitive drum 41 than the second inner surface 22A.

As shown in FIG. 5, the third wall 20C has a first guide portion 80, a second guide portion 90, and a slit SL.

The first guide portion 80 has a first rail 81 and a second rail 82 . The first rail 81 and the second rail 82 are positioned inside the slot 20 . The first rail 81 and the second rail 82 protrude from the third wall 20C. The first rail 81 and the second rail 82 extend from one axial end of the slot 20 to the other axial end. The first rail 81 and the second rail 82 guide the drum cartridge 40 in the axial direction and restrict the drum cartridge 40 from moving in the orthogonal direction when the drum cartridge 40 is attached or detached. Further, the first rail 81 and the second rail 82 regulate the drum cartridge 40 so as not to move in the orthogonal direction when the drum cartridge 40 is mounted.

The second guide portion 90 is an example of a guide portion that guides the developing cartridge when the developing cartridge is installed. The second guide portion 90 regulates the developing roller 51 so as not to come into contact with the photosensitive drum 41 when the developing cartridge 50 is attached or detached. Allows 41 touches.

The second guide portion 90 has a third rail 91 and a fourth rail 92 . The third rail 91 and the fourth rail 92 are positioned inside the slot 20 . The third rail 91 and the fourth rail 92 protrude from the third wall 20C. The third rail 91 and the fourth rail 92 extend from one axial end of the slot 20 to the other axial end. The first rail 81, the second rail 82, the third rail 91, and the fourth rail 92 are arranged in parallel in this order from one end side in the orthogonal direction.

The third rail 91 includes a first rail portion 91X, a second rail portion 91Y, and a third rail portion 91Z. A first opening 91A is positioned between the first rail portion 91X and the second rail portion 91Y in the axial direction. Also, in the axial direction, the second opening 91B is positioned between the second rail portion 91Y and the third rail portion 91Z.
The first opening 91A is located at one end of the slot 20 in the axial direction. The second opening 91B is positioned at the other end of the slot 20 in the axial direction. The axial dimension K1 of the first opening 91A is smaller than the axial dimension K2 of the second opening 91B (see FIG. 3).

The fourth rail 92 protrudes from the third wall 20C. Specifically, the fourth rail 92 has a first portion 92A and a second portion 92B. The first portion 92A is a portion protruding upward from the third wall 20C. The second portion 92B extends from the upper end of the first portion 92A toward one side in the orthogonal direction.

The third rail 91 and the fourth rail 92 guide the developing cartridge 50 in the axial direction and restrict it from moving in the orthogonal direction when the developing cartridge 50 is attached or detached. Further, when the developing cartridge 50 is attached or detached, the fourth rail 92 engages with a first engaging portion 55 and a second engaging portion 56, which will be described later, to regulate the vertical movement of the developing cartridge 50. .

The slit SL extends in the axial direction. A laser beam emitted from the exposure unit SU can pass through the slit SL.

As shown in FIG. 5, the developer cartridge 50 has a first pressing member 53, a second pressing member 54, a first engaging portion 55, a second engaging portion 56, and a shaft support portion 57. ing.

As shown in FIG. 4, the developing housing 52 has a first hole 52A and a second hole 52B. The first hole 52A and the second hole 52B are open on the other side in the orthogonal direction. The first hole 52A is positioned at one end of the developing housing 52 in the axial direction. The second hole 52B is positioned at the other end of the developing housing 52 in the axial direction. A flange 52C that prevents the first pressing member 53 from coming off is provided on the edge of the first hole 52A. A flange 52D that prevents the second pressing member 54 from coming off is provided at the edge of the second hole 52B.

The first pressing member 53 is engaged with the first hole 52A and held so as to be slidable in the orthogonal direction. The first pressing member 53 is prevented from slipping out of the first hole 52A by contacting the flange 53A provided at the proximal end with the flange 52C of the first hole 52A. A first contact surface 53</b>B located at the tip of the first pressing member 53 protrudes from the developing housing 52 . The first contact surface 53B is rounded when viewed from above. A spring 53S is provided between the base end surface of the first pressing member 53 and the bottom of the first hole 52A. The spring 53S always urges the first pressing member 53 toward the other side in the orthogonal direction.

When the developer cartridge 50 is mounted in the slot 20, the tip of the first pressing member 53 contacts the first inner surface 21A of the slot 20 at the first contact surface 53B. The first contact surface 53B is a surface that contacts the first inner surface 21A when the developer cartridge 50 is mounted in the slot 20 while the drum cartridge 40 is mounted in the slot 20 .

The second pressing member 54 is engaged with the second hole 52B and held so as to be slidable in the orthogonal direction. The second pressing member 54 is prevented from slipping out of the second hole 52B by contacting the flange 54A provided at the proximal end with the flange 52D of the second hole 52B. A second contact surface 54</b>B located at the tip of the second pressing member 54 protrudes from the developing housing 52 . The second contact surface 54B is rounded when viewed from above. A spring 54S is provided between the base end surface of the second pressing member 54 and the bottom of the second hole 52B. The spring 54S always urges the second pressing member 54 toward the other side in the orthogonal direction.

When the developer cartridge 50 is mounted in the slot 20, the tip of the second pressing member 54 contacts the second inner surface 22A of the slot 20 at the second contact surface 54B. The second contact surface 54B is a surface that contacts the second inner surface 22A when the developer cartridge 50 is mounted in the slot 20 while the drum cartridge 40 is mounted in the slot 20 .

When the developing cartridge 50 is not attached to the slot 20, the distance L1 from the first contact surface 53B to the developing roller 51 is greater than the distance L2 from the second contact surface 54B to the developing roller 51. FIG. In other words, when the developer cartridge 50 is not attached to the slot 20, the first contact surface 53B is located farther from the developing roller 51 than the second contact surface.

A distance L3 from the first inner surface 21A to the developing roller 51 is greater than a distance L4 from the second inner surface 22A to the developing roller 51. As shown in FIG.

When the drum cartridge 40 and the developing cartridge 50 are installed in the slot 20, the distance L3 from the first contact surface 53B to the developing roller 51 is greater than the distance L4 from the second contact surface 54B to the developing roller 51. That is, when the drum cartridge 40 and the developing cartridge 50 are installed in the slot 20, the first contact surface 53B is located farther from the developing roller 51 than the second contact surface 54B.

When the drum cartridge 40 and the developing cartridge 50 are installed in the slot 20, the distance L3 from the first contact position between the first inner surface 21A and the first contact surface 53B to the developing roller 51 is the distance between the second inner surface 22A and the developing roller 51. It is longer than the distance L4 from the second contact position with the second contact surface 54B to the developing roller 51 . That is, the first contact position between the first inner surface 21A and the first contact surface 53B is farther from the developing roller 51 than the second contact position between the second inner surface 22A and the second contact surface 54B.

When the developing cartridge 50 is installed in the slot 20 in a state where the drum cartridge 40 is installed in the main body housing 2, the tip of the second pressing member 54 (indicated by the two-dot chain line in FIG. 4) is pushed from the developing roller 51. is smaller than the distance L3 from the first inner surface 21A to the developing roller 51. Therefore, when the developing cartridge 50 is attached to the slot 20 with the drum cartridge 40 attached to the main housing 2, the second contact surface 54B does not come into contact with the first inner surface 21A ( See FIG. 6(a)).

The first pressing member 53 and the second pressing member 54 are examples of pressing members. In this embodiment, the pressing member includes a first pressing member 53 and a second pressing member 54 . The first pressing member 53 and the second pressing member 54 are in contact with the first contact surface 53B at the first inner surface 21A and in contact with the second contact surface 54B at the second inner surface 22A. is pressed against the photosensitive drum 41 .

As shown in FIG. 5 , the first engaging portion 55 is positioned on the bottom surface of the developing housing 52 . The first engaging portion 55 has a first body portion 55A and a first extension portion 55B. The first body portion 55A protrudes downward from the bottom surface of the developing housing 52 . The first extending portion 55B extends from the lower end of the first main body portion 55A to the other end side in the orthogonal direction.

The first body portion 55A has a first surface 55C and a second surface 55D. The first surface 55C extends along the axial direction. The first surface 55C is a surface that comes into contact with the third rail 91 in the process of attaching and detaching the developing cartridge 50 . The second surface 55D extends obliquely from the first surface 55C. Specifically, the second surface 55D extends obliquely from the end of the first surface 55C toward the other side in the orthogonal direction as it moves toward one side in the axial direction. The second surface 55D is a surface that contacts the first rail portion 91X of the third rail 91 when the developing cartridge 50 is pulled out from the slot 20. As shown in FIG.

The first body portion 55A is a portion that is restricted by the third rail 91 so as not to move to one side in the orthogonal direction. The first extending portion 55B is regulated by the first portion 92A of the fourth rail 92 so as not to move to the other side in the orthogonal direction, and is regulated by the second portion 92B of the fourth rail 92 so as not to move upward. This is the part where

The axial dimension K3 of the first engaging portion 55 is smaller than the axial dimension K4 of the second engaging portion 56 . The axial dimension K3 of the first engaging portion 55 is smaller than the axial dimension K1 of the first opening 91A. The axial dimension K3 of the first engaging portion 55 is smaller than the axial dimension K2 of the second opening 91B.

The second engaging portion 56 is positioned on the lower surface of the developing housing 52 . The second engaging portion 56 has a second body portion 56A and a second extension portion 56B. The second main body portion 56A protrudes downward from the bottom surface of the developing housing 52 . The second extending portion 56B extends from the lower end of the second main body portion 56A to the other end side in the orthogonal direction.

The second body portion 56A has a third surface 56C and a fourth surface 56D. The third surface 56C extends along the axial direction. The third surface 56C is a surface that contacts the third rail 91 in the process of attaching and detaching the developing cartridge 50 .
The fourth surface 56D extends obliquely from the third surface 56C. Specifically, the fourth surface 56D extends from the end of the third surface 56C while being inclined with respect to the axial direction so as to move toward the other side in the orthogonal direction as it moves toward one side in the axial direction. The fourth surface 56</b>D is a surface that contacts the second rail portion 91</b>Y of the third rail 91 when the developing cartridge 50 is pulled out from the slot 20 .

The second body portion 56A is a portion that is restricted by the third rail 91 so as not to move to one side in the orthogonal direction. The second extending portion 56B is regulated by the first portion 92A of the fourth rail 92 so as not to move to the other side in the orthogonal direction, and is regulated by the second portion 92B of the fourth rail 92 so as not to move upward. This is the part where

The axial dimension K4 of the second engaging portion 56 is larger than the axial dimension K1 of the first opening 91A. The axial dimension K4 of the second engaging portion 56 is smaller than the axial dimension K2 of the second opening 91B.

The shaft support portion 57 extends from one end surface of the developing housing 52 in the axial direction to one side in the orthogonal direction. The shaft support portion 57 has an elongated hole 57A. The long hole 57A engages with a boss 43 provided on one end face of the drum cartridge 40 in the axial direction.

Next, the action when the drum cartridge 40 and the developing cartridge 50 are attached will be described.
As shown in FIG. 6A, first, the drum cartridge 40 is mounted in the slot 20. As shown in FIG. Then, the second engaging portion 56 of the developing cartridge 50 is engaged with the third rail 91 and the fourth rail 92 . At this time, the developing roller 51 is not in contact with the photosensitive drum 41 . Also, the second contact surface 54B of the developer cartridge 50 does not come into contact with the first inner surface 21A of the slot 20 . At this time, since the axial dimension K4 of the second engaging portion 56 is larger than the axial dimension K1 of the first opening 91A, the second engaging portion 56 passes through without entering the first opening 91A.

When the developing cartridge 50 is pushed toward the inner side of the slot 20 from the state shown in FIG. 6A, the first pressing member 53 is pushed against the first inclined surface 21B of the first projecting portion 21 as shown in FIG. 6B. The second pressing member 54 contacts the second inclined surface 22B of the second projecting portion 22 while contacting.

When the developing cartridge 50 is pushed toward the inner side of the slot 20 from the state shown in FIG. 6(b), the first pressing member 53 is pushed by the first inclined surface 21B and is pushed toward the developing roller 51 as shown in FIG. 6(c). At the same time, the second pressing member 54 is pushed by the second inclined surface 22B and slides toward the developing roller 51 side. At this time, the first engaging portion 55 and the second engaging portion 56 are in contact with the third rail 91 . Therefore, the developer cartridge 50 cannot move to one side in the orthogonal direction. As a result, the developing roller 51 is not in contact with the photosensitive drum 41 .

When the developing cartridge 50 is pushed toward the inner side of the slot 20 from the state shown in FIG. 6(c), the first pressing member 53 comes into contact with the first inner surface 21A as shown in FIG. 6(d). Similarly, the second pressing member 54 contacts the second inner surface 22A. Thus, the first contact surface 53B of the first pressing member 53 contacts the first inner surface 21A. Also, the second contact surface 54B of the second pressing member 54 contacts the second inner surface 22A. At this time, part of the first engaging portion 55 enters the first opening 91A, and part of the second engaging portion 56 enters the second opening 91B.

Next, the operation of removing the developing cartridge 50 will be described.
When removing the developer cartridge 50 from the slot 20, the developer cartridge 50 is pulled out to one side in the axial direction from the state shown in FIG. 6(d). Then, the second surface 55D of the first engaging portion 55 contacts the first rail portion 91X of the third rail 91, and the fourth surface 56D of the second engaging portion 56 contacts the second rail portion 91X of the third rail 91. It contacts with the rail portion 91Y.

When the developing cartridge 50 is further pulled out from this state, as shown in FIG. 6C, the second surface 55D of the first engaging portion 55 is pushed by the first rail portion 91X, so that the second surface 55D is pushed to the other side in the orthogonal direction. Moving. Then, the first surface 55</b>C of the first engaging portion 55 comes into contact with the third rail 91 . Similarly, the second engaging portion 56 moves to the other side in the orthogonal direction because the fourth surface 56D is pushed by the second rail portion 91Y. Then, the third surface 56</b>C of the second engaging portion 56 comes into contact with the third rail 91 . Therefore, when the developing cartridge 50 is pulled out to one side in the axial direction, the developing cartridge 50 is pushed to the other side in the orthogonal direction, so that the contact between the developing roller 51 and the photosensitive drum 41 is released.

After that, the developing cartridge 50 is guided by the third rail 91 to be restrained from moving to one side in the orthogonal direction, and the developing roller 51 is pulled out in the axial direction without contacting the photosensitive drum 41 .

According to the image forming apparatus 1 described above, when the developing cartridge 50 is inserted into the slot 20 while the drum cartridge 40 is inserted into the slot 20 , the developing roller 51 presses the photosensitive drum 41 . can. Furthermore, when the drum cartridge 40 is attached to the main housing 2 of the image forming apparatus 1 and the developing cartridge 50 is attached to the main housing 2 in the axial direction, the developing cartridge and the drum cartridge interference can be suppressed.

Further, when the developing cartridge 50 is installed in the slot 20 with the drum cartridge 40 installed in the main housing 2, the second contact surface 54B does not come into contact with the first inner surface 21A. Therefore, it is easy to mount the developing cartridge 50 in the slot 20 .

Also, when the developer cartridge 50 is mounted in the slot 20, the first inclined surface 21B guides the first contact surface 53B to the first inner surface 21A, and the second inclined surface 22B guides the second contact surface 54B to the second inner surface 21A. Guide to 22A. Therefore, the developing cartridge 50 can be easily attached.

Further, the second guide portion 90 regulates the developing roller 51 so as not to contact the photosensitive drum 41 when the developing cartridge 50 is attached or detached. Therefore, when the drum cartridge 40 is attached to the main body housing 2 of the image forming apparatus 1 and the developing cartridge 50 is attached to the main body housing 2 in the axial direction, the developing cartridge and the drum cartridge are separated from each other. can suppress interference with

Next, a second embodiment of the present disclosure will be described. In the following description, members having substantially the same structure as in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the first form, the first inner surface and the second inner surface were positioned at the projecting portion of the slot, and the first contact surface and the second contact surface were positioned at the tip of the pressing member. However, the first inner surface and the second inner surface may be located at the tip of the pressing member, and the first contact surface and the second contact surface may be located at the projecting portion of the developing housing.

For example, in the second embodiment shown in FIG. 7, the first inner surface 121A is located at the tip of the first pressing member 121. As shown in FIG. A spring 121S is provided between the base end surface of the first pressing member 121 and the slot 120 . The spring 121S always urges the first pressing member 121 toward one side in the orthogonal direction. The second inner surface 122A is located at the tip of the second pressing member 122 . A spring 122S is provided between the base end surface of the second pressing member 122 and the slot 120 . The spring 122S always urges the second pressing member 122 toward one side in the orthogonal direction.

The first contact surface 153B is located at the tip of the first projecting portion 153 projecting from the developing housing 152 . The second contact surface 154B is located at the tip of the second projecting portion 154 projecting from the developing housing 152 .

When the developer cartridge 150 is mounted in the slot 120 from the state shown in FIG. 7, the first inner surface 121A contacts the first contact surface 153B. Similarly, second interior surface 122A contacts second contact surface 154B.

The distance M1 from the first inner surface 121A to the photoreceptor drum 41 is the same as the distance M3 from the first contact surface 153B to the photoreceptor drum 41 when the developing cartridge 150 is attached to the main housing 2 . Similarly, the distance M2 from the second inner surface 122A to the photoreceptor drum 41 is the same distance as the distance M4 from the second contact surface 154B to the photoreceptor drum 41 when the developing cartridge 150 is attached to the main housing 2. becomes.

In the state where the drum cartridge 40 and the developing cartridge 150 are attached to the main body housing 2, the distance M3 from the first inner surface 121A to the photosensitive drum 41 is greater than the distance M4 from the second inner surface 122A to the photosensitive drum 41. is also big. That is, when the drum cartridge 40 and the developing cartridge 150 are attached to the main housing 2, the first inner surface 121A is located farther from the photosensitive drum 41 than the second inner surface 122A.

Further, when the developing cartridge 150 is installed in the slot 120 with the drum cartridge 40 installed in the main housing 2, the second contact surface 154B does not come into contact with the first inner surface 121A.

According to the second embodiment described above, the developing roller 51 can press the photosensitive drum 41 by inserting the developing cartridge 150 into the slot 120 with the drum cartridge 40 inserted into the slot 120 . Furthermore, when the drum cartridge 40 is attached to the main housing 2 of the image forming apparatus 1 and the developing cartridge 150 is attached to the main housing 2 in the axial direction, the developing cartridge and the drum cartridge interference can be suppressed.

Next, a third embodiment of the present disclosure will be described. In the following description, members having substantially the same structure as in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the first embodiment, a part of the main body housing is provided with the first inner surface and the second inner surface, but another member may be provided with the first inner surface and the second inner surface.

For example, as shown in FIG. 8, four drum cartridges 240 and four developer cartridges 50 can be inserted into the slots 220 in the third embodiment. In this third embodiment, the frame 242 of the adjacent drum cartridge 140 is provided with a first protrusion 221 having a first inner surface 221A. Similarly, a second projection 222 having a second inner surface 222A is provided on the frame 242 of the adjacent drum cartridge 240. As shown in FIG.

According to the third embodiment, too, the developing roller 51 can be pressed against the photosensitive drum 41 by inserting the developing cartridge 50 into the slot 220 as in the first embodiment. Furthermore, when the drum cartridge 40 is attached to the main housing 2 of the image forming apparatus 1 and the developing cartridge 50 is attached to the main housing 2 in the axial direction, the developing cartridge and the drum cartridge interference can be suppressed. In the third embodiment, since there is no wall between each drum cartridge 240 and each developing cartridge 50, it is possible to make it compact in the orthogonal direction.

Next, a fourth embodiment of the present disclosure will be described. In the following description, members having substantially the same structure as in the second embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 9, in the fourth embodiment, a first pressing member 121 having a first inner surface 121A and a second pressing member 122 having a second inner surface 122A are provided on the frame 342 of the adjacent drum cartridge 340. It is

According to the fourth embodiment, the developing roller 51 can press the photosensitive drum 41 by inserting the developing cartridge 150 into the slot 320 as in the second embodiment. Further, when the drum cartridge 340 is attached to the main housing 2 of the image forming apparatus 1 and the developing cartridge 150 is attached to the main housing 2 in the axial direction, the developing cartridge and the drum cartridge interference can be suppressed. In the fourth embodiment, since there is no wall between each drum cartridge 340 and each developing cartridge 150, the size can be reduced in the orthogonal direction.

In each of the above-described embodiments, the inclination of the first inclined surface of the first internal surface and the inclination of the second inclined surface of the second internal surface are the same angle of inclination, but they may be different angles of inclination.

For example, in the first modification shown in FIG. 10, the inclination of the first inclined surface 421B of the first protrusion 421 and the inclination of the second inclined surface 422B of the second protrusion 422 are different. Specifically, the inclination angle θ1 with respect to the axial direction of the first inclined surface 421B is smaller than the inclination angle θ2 with respect to the axial direction of the second inclined surface 422B.

As in the first modified example, by making the inclination angle θ1 of the first inclined surface 421B different from the inclination angle θ2 of the second inclined surface 422B, the pressing force of the first pressing member 453 and the second pressing member 454 is increased. Tendency can be adjusted.

Also, in the above-described first embodiment, a plurality of projecting portions projecting from the inner surface of the slot 20 are provided, but the number of projecting portions may be one. For example, in the second modification shown in FIG. 11(a), the first inner surface 521A and the second inner surface 522A are connected by the third inclined surface 523A, and there is one projecting portion. This form also provides the same effects as the first embodiment.

Further, in the above-described second embodiment, a plurality of protrusions protruding from the developing housing are provided, but the number of protrusions may be one. For example, in the third modification shown in FIG. 11B, the first inner surface 621A and the second inner surface 622A are connected by a third inclined surface 623A, and there is one projecting portion projecting from the developing housing 652. is. This form also provides the same effects as the second embodiment.

Further, in the above-described first embodiment, the first pressing member and the second pressing member are biased by the spring, but the spring itself may be the pressing member.

For example, in the fourth modification shown in FIG. 12A, the developer cartridge 750 has a first leaf spring 753 and a second leaf spring 754 in the developer housing 752 . The first leaf spring 753 and the second leaf spring 754 are fixed to the developing housing 752 . The first contact surface 753B is located at the tip of the first plate spring 753. As shown in FIG. The second contact surface 754B is located at the tip of the second leaf spring 754. As shown in FIG.

According to the fourth modification, the developing roller 51 can press the photosensitive drum 41 by inserting the developing cartridge 750 into the slot 20 as in the above-described embodiments. Note that the spring is not limited to a leaf spring, and may be a torsion spring or the like. According to this fourth modification, the number of parts can be reduced.

Also, in the above-described second embodiment, the first inner surface 121A is provided at the tip of the first pressing member 121, but the first inner surface may be provided at the tip of the biasing member. Similarly, although the second inner surface 122A is provided at the tip of the second pressing member 122, the second inner surface may be provided at the tip of the biasing member.

For example, in a fifth modification shown in FIG. 12B, a first leaf spring 821 and a second leaf spring 822 are provided on the inner surface of the slot 820 . The first inner surface 821A is located at the tip of the first plate spring 821. As shown in FIG. The first inner surface 822A is located at the tip of the second plate spring 822. As shown in FIG.

According to the fifth modification, too, the developing roller 51 can press the photosensitive drum 41 by inserting the developing cartridge 150 into the slot 820 as in the second embodiment. Note that the spring is not limited to a leaf spring, and may be a torsion spring or the like. According to this fifth modification, the number of parts can be reduced.

In each of the above-described embodiments, the image forming apparatus 1 is a color printer, but the present invention is not limited to this, and the present invention can be applied to other image forming apparatuses such as monochrome printers, copiers, multifunction machines, and the like. You may

Each element described in the above-described embodiment and modified examples may be combined arbitrarily and implemented.

REFERENCE SIGNS LIST 1 image forming apparatus 2 main body housing 2A cover 2E discharge section 20 slot 21 first protrusion 21A first inner surface 21B first inclined surface 22 second protrusion 22A second inner surface 22B second inclined surface 40 drum cartridge 41 photosensitive body drum 42 frame 50 developing cartridge 51 developing roller 52 developing housing 53 first pressing member 53B first contact surface 54 second pressing member 54B second contact surface 63 intermediate transfer belt X1 first axis X2 second axis

Claims (13)

a drum cartridge having a photoreceptor drum rotatable about an axially extending first axis;
a developing cartridge having a developing roller rotatable about a second shaft extending in the axial direction and a developing housing capable of accommodating toner;
A body housing having a slot extending in the axial direction, wherein the slot allows attachment and detachment of the drum cartridge in the axial direction and allows attachment and detachment of the developing cartridge in the axial direction. a body housing that allows,
a cover having a closed state that closes the slot and an open state that opens the slot;
a first inner surface located inside the slot;
a second inner surface positioned inside the slot and positioned farther from the cover in the axial direction than the first inner surface;
An image forming apparatus comprising
The development housing further includes:
a first contact surface that contacts the first inner surface when the developer cartridge is mounted in the slot in a state where the drum cartridge is mounted in the slot;
a second contact surface that contacts the second inner surface when the developer cartridge is mounted in the slot in a state where the drum cartridge is mounted in the slot;
with
a first contact position between the first inner surface and the first contact surface is further away from the developing roller than a second contact position between the second inner surface and the second contact surface;
In the image forming apparatus, the developing roller is further moved to the photosensitive drum in a state in which the first inner surface is in contact with the first contact surface and the second inner surface is in contact with the second contact surface. An image forming apparatus, comprising: a pressing member that presses against the image forming apparatus. The image forming apparatus further includes an intermediate transfer belt positioned above the drum cartridge and the developing cartridge in a state in which the drum cartridge and the developing cartridge are mounted in the main housing, the intermediate transfer belt comprising the drum cartridge and the developing cartridge. 2. The image forming apparatus according to claim 1, further comprising an intermediate transfer belt with which a surface of said photosensitive drum contacts when said developing cartridge is attached to said main housing. 3. The image forming apparatus according to claim 2, further comprising a discharge section positioned above the intermediate transfer belt for discharging the recording sheet. 3. The first inner surface is located farther from the photoreceptor drum than the second inner surface when the drum cartridge is attached to the main housing. The image forming apparatus according to any one of . 5. The image forming apparatus according to claim 1, wherein the first contact surface is located farther from the developing roller than the second contact surface. 2. The second contact surface does not come into contact with the first inner surface when the developing cartridge is mounted in the slot with the drum cartridge mounted in the main housing. The image forming apparatus according to claim 5 . The first inner surface is located at the tip of the first projecting portion projecting from the slot,
The image forming apparatus according to any one of claims 1 to 6, wherein the second inner surface is positioned at a tip of a second projecting portion projecting from the slot. The pressing member includes a first pressing member and a second pressing member,
The first contact surface is located at the tip of the first pressing member,
8. The image forming apparatus according to claim 7, wherein the second contact surface is positioned at the tip of the second pressing member. The pressing member includes a first pressing member and a second pressing member,
The first inner surface is located at the tip of the first pressing member,
7. The image forming apparatus according to claim 1, wherein the second inner surface is positioned at the tip of the second pressing member. The first contact surface is positioned at the tip of a first projecting portion projecting from the developing housing,
10. The image forming apparatus according to claim 9, wherein the second contact surface is positioned at a tip of a second projecting portion projecting from the developing housing. the main housing has a first inclined surface located on one side of the first inner surface in the axial direction;
The first inclined surface extends away from the developing roller as it approaches the cover from the first inner surface when the drum cartridge and the developing cartridge are attached to the main housing. 11. The image forming apparatus according to any one of claims 1 to 10. the main housing has a second inclined surface located on one side of the second inner surface in the axial direction,
The second inclined surface extends away from the developing roller as it approaches the cover from the second contact surface in a state in which the drum cartridge and the developing cartridge are attached to the main housing. 12. The image forming apparatus according to any one of claims 1 to 11. The slot has a guide portion that guides the developing cartridge when the developing cartridge is installed,
The guide section
regulating the developing roller so that it does not come into contact with the photosensitive drum when the developing cartridge is attached or detached;
12. The image forming apparatus according to claim 1, wherein contact between the developing roller and the photosensitive drum is allowed when the developing cartridge is mounted in the slot.

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