JP7226297B2 - image forming device - Google Patents

Description

The present disclosure relates to an image forming apparatus that includes a drum cartridge and a developing cartridge that can be attached to and detached from a main housing.

Conventionally, there is known an image forming apparatus in which a drum cartridge and a developing cartridge can be separately attached to and detached from a main body housing (see Japanese Patent Application Laid-Open No. 2002-200013). In this technology, the drum cartridge and the developing cartridge are detachable in the axial direction of the photosensitive drum. The body housing has an opening for inserting the drum cartridge and the developer cartridge, and a slot into which the drum cartridge and the developer cartridge are mounted.
In addition, the slot includes a guide portion for guiding the drum cartridge during attachment and detachment, and a guide portion for guiding the developing cartridge during attachment and detachment.

JP 2017-173805 A

In the configuration disclosed in Patent Document 1, the drum cartridge and the developing cartridge are installed in respective slots. Also, as the number of guide portions increases, the width of each guide portion and the interval between adjacent guide portions are narrowed.
With such a configuration, it becomes difficult for the user to install the drum cartridge and the developing cartridge into the slots of the main housing.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an image forming apparatus in which a drum cartridge can be easily attached to a main housing even when the width of the guide portion is narrowed.

In order to solve the above-described problems, an image forming apparatus according to the present invention provides a main body housing having an opening, the main body housing having a slot extending in a first direction toward the inside of the main body housing from the opening; A drum cartridge having a photosensitive drum rotatable about a first axis extending in the first direction, the drum cartridge being mountable in the slot through the opening in the first direction; A developing cartridge having a developing roller rotatable about two axes, the developing cartridge being mountable in the slot through the opening in the first direction. The developer cartridge is aligned with the drum cartridge in a second direction crossing the first direction in a state in which the drum cartridge and the developer cartridge are mounted in the slot.
The body housing has a drum guide groove or a drum guide protrusion extending in the first direction for guiding the drum cartridge.
The drum cartridge has a drum projection that extends in the first direction and fits into the drum guide groove, or a drum groove that extends in the first direction and fits into the drum guide projection.
When the body housing has the drum guide groove, the width of the drum guide groove in the second direction narrows from the opening toward the inside of the body housing, or the drum in the second direction The width of the protrusion becomes narrower toward the inside of the main housing from the opening when the drum cartridge is mounted in the slot.
When the body housing has the drum guide projection, the width of the drum guide projection in the second direction increases toward the inside of the body housing from the opening, or the drum in the second direction The width of the groove becomes wider toward the inside of the main housing from the opening when the drum cartridge is mounted in the slot.

According to this configuration, when the main body housing has the drum guide groove, the drum cartridge has the drum protrusion that fits into the drum guide groove, and when the drum cartridge is mounted in the slot, the drum protrusion in the second direction can be positioned. The width is substantially equal to the minimum width of the drum guide groove in the second direction on the mounting direction tip (end away from the opening) side. The width of the drum guide groove in the second direction narrows from the opening toward the interior of the main housing, or the width of the drum protrusion in the second direction decreases from the opening toward the interior of the main housing. narrow.
Further, when the main body housing has the drum guide projection, the drum cartridge has a drum groove in which the drum guide projection fits, and when the drum cartridge is mounted in the slot, the width of the drum groove in the second direction is It is substantially equal to the maximum width of the drum guide protrusion in the second direction on the direction leading end side. The width of the drum guide projection in the second direction increases toward the inside of the main housing from the opening, or the width of the drum groove in the second direction increases toward the inside of the main housing from the opening. It's wide.
Since the width of the drum guide groove on the opening side is larger than the width of the drum protrusion on the front end side in the mounting direction, the drum cartridge can be easily mounted in the slot. Similarly, since the width of the drum guide projection on the opening side is smaller than the width of the drum groove on the leading end side in the mounting direction, the drum cartridge can be easily mounted in the slot.

In the image forming apparatus described above, the main housing has the drum guide groove, the drum cartridge has the drum protrusion, and the width of the drum guide groove in the second direction is the width from the opening to the width of the drum guide groove. It may become narrower toward the inside of the body housing.
In this configuration, the width of the drum projection in the second direction may become narrower from the opening toward the interior of the main housing when the drum cartridge is mounted in the slot.

In the image forming apparatus described above, the drum guide groove may have a tapered shape.
In this configuration, the drum protrusion may have a tapered shape.

According to this, by having a tapered shape, it is possible to more smoothly mount the drum cartridge in the slot.

In the image forming apparatus described above, the main housing may have a development guide groove or a development guide protrusion extending in the first direction for guiding the development cartridge.
The developing cartridge may have a developing protrusion extending in the first direction and fitted into the developing guide groove, or a developing groove extending in the first direction and fitted with the developing guide protrusion.
When the body housing has the development guide groove, the width of the development guide groove in the second direction becomes narrower toward the inside of the body housing from the opening, or the development in the second direction. The width of the projection becomes narrower toward the inside of the main housing from the opening when the developing cartridge is installed in the slot.
When the body housing has the development guide projection, the width of the development guide projection in the second direction increases toward the inside of the body housing from the opening, or the development in the second direction The width of the groove becomes wider toward the inside of the main housing from the opening when the developing cartridge is mounted in the slot.

According to this configuration, when the main body housing has the development guide groove, the drum cartridge has the development projection that fits into the development guide groove, and when the drum cartridge is mounted in the slot, the development projection is positioned in the second direction. The width is substantially equal to the minimum width of the developing guide groove in the second direction on the mounting direction leading end (end away from the opening) side. Then, the width of the development guide groove in the second direction narrows from the opening toward the inside of the main housing, or the width of the development projection in the second direction decreases from the opening toward the inside of the main housing. narrow.
Further, when the main housing has the development guide projection, the development cartridge has a development groove in which the development guide projection fits, and when the development cartridge is mounted in the slot, the width of the development groove in the second direction is It is substantially equal to the maximum width of the development guide protrusion in the second direction at the direction leading end side. Then, the width of the development guide projection in the second direction increases from the opening toward the inside of the main housing, or the width of the development groove in the second direction increases from the opening toward the inside of the main housing. It's wide.
Since the width of the developing guide groove on the opening side is larger than the width of the developing projection on the leading end side in the mounting direction, the developing cartridge can be easily mounted in the slot. Similarly, since the width of the development guide protrusion on the opening side is smaller than the width of the development groove on the leading end side in the mounting direction, the development cartridge can be easily mounted in the slot.

In the image forming apparatus described above, the main housing has the development guide projection, the development cartridge has the development groove, and the width of the development guide projection in the second direction is the width from the opening to the width of the development guide projection. It may be widened toward the inside of the main housing.
In this configuration, the width of the developing groove in the second direction may increase from the opening toward the inside of the main housing when the developing cartridge is mounted in the slot.

In the image forming apparatus described above, the development guide protrusion may have a tapered shape.
In this configuration, the development groove may have a tapered shape.

According to this, by having a tapered shape, it is possible to more smoothly mount the developing cartridge in the slot.

The image forming apparatus may include an intermediate transfer belt positioned above the drum cartridge and the developing cartridge when the drum cartridge and the developing cartridge are attached to the main housing.
The body housing may have a drum guide surface for guiding the drum cartridge, the drum guide surface being aligned with the drum guide groove or the drum guide protrusion in the second direction. The drum cartridge may have a drum contact surface that contacts the drum guide surface when the drum cartridge is mounted in the slot.
The drum guide surface may be configured to approach the intermediate transfer belt from the opening toward the inside of the main housing.

According to this, since the distance between the drum guide surface and the intermediate transfer belt becomes large on the opening side of the main housing, when the drum cartridge is installed in the slot, the photosensitive drum is inserted from a position where it is difficult for the intermediate transfer belt to hit. can do.

In the image forming apparatus described above, the drum contact surface may be configured so as to approach the intermediate transfer belt from the opening toward the interior of the main housing when the drum cartridge is mounted in the slot. good.

In the image forming apparatus described above, the main housing has a development guide surface for guiding the development cartridge, the development guide surface being aligned with the development guide groove or the development guide protrusion in the second direction. may be The developer cartridge may have a developer contact surface that contacts the developer guide surface when the developer cartridge is mounted in the slot.
The development guide surface may be configured to approach the intermediate transfer belt from the opening toward the inside of the main housing.

According to this, since the distance between the development guide surface and the intermediate transfer belt becomes large on the opening side of the main housing, when the development cartridge is installed in the slot, it is possible to insert the development cartridge from a position where it is difficult to hit the intermediate transfer belt. can.

In the image forming apparatus described above, the development contact surface is configured to approach the intermediate transfer belt from the opening toward the inside of the main housing when the developing cartridge is mounted in the main housing. may be

In the image forming apparatus described above, the developer cartridge includes a first developer cartridge containing a developer of a first color and a second developer cartridge containing a developer of a second color different from the first color. may contain.
When the body housing has the development guide groove, the development guide groove includes a first development guide groove that guides the first development cartridge and a second development guide groove that guides the second development cartridge. , the length of the first development guide groove in the second direction may be different from the length of the second development guide groove in the second direction.
Further, when the main housing has the development guide protrusion, the development guide protrusion includes a first development guide protrusion that guides the first development cartridge, a second development guide protrusion that guides the second development cartridge, and the length of the first development guide protrusion in the second direction may be different from the length of the second development guide protrusion in the second direction.

According to this, the width of the development guide groove or the development guide protrusion in the second direction is different corresponding to the different color of the development cartridge, so that it is possible to prevent mis-insertion of the development cartridge.

In the image forming apparatus described above, the developer cartridge includes a first developer cartridge containing a developer of a first color and a second developer cartridge containing a developer of a second color different from the first color. may contain. The drum cartridges may include a first drum cartridge corresponding to the first developer cartridge and a second drum cartridge corresponding to the second developer cartridge.
When the body housing has the drum guide groove, the drum guide groove includes a first drum guide groove that guides the first drum cartridge and a second drum guide groove that guides the second drum cartridge. The length of the first drum guide groove in the second direction may be the same as the length of the second drum guide groove in the second direction.
Further, when the main housing has the drum guide projection, the drum guide projection includes a first drum guide projection that guides the first drum cartridge and a second drum guide projection that guides the second drum cartridge. , wherein the length of the first drum guide protrusion in the second direction may be the same as the length of the second drum guide protrusion in the second direction.

According to this, a common drum cartridge can be used corresponding to a plurality of developing cartridges, so that the manufacturing cost can be reduced.

In the image forming apparatus described above, the main housing has a cover that opens and closes the opening, and a side wall that is positioned away from the cover in the first direction when the cover is in the closed position. , the sidewall may have a first protrusion or first slot and a second protrusion or second slot.
The drum cartridge has a long drum hole into which the first projection fits or a drum projection into which the first long hole fits when the drum cartridge is attached to the main housing. may have a development slot into which the second projection fits or a development projection to fit into the second slot when the development cartridge is mounted in the main housing.

According to this, the drum cartridge and the developing cartridge can be brought into contact with and separated from the intermediate transfer belt.

In the image forming apparatus described above, the intermediate transfer belt may be positioned above the drum cartridge and the developing cartridge when the drum cartridge and the developing cartridge are mounted in the main housing.
In such a configuration, the paper discharge section may be positioned above the intermediate transfer belt.

According to the present invention, it is possible to provide an image forming apparatus in which the drum cartridge can be easily attached to the main housing.

1 is a cross-sectional view showing a schematic configuration of a color printer according to one embodiment of the present invention; FIG. FIG. 4 is a perspective view showing a state in which the cover of the main body housing is opened, and shows a state in which the drum cartridge and the developing cartridge are removed from the slots; They are a perspective view (a) of the drum cartridge, a front view (b) of the drum cartridge, and a bottom view (c) of the drum cartridge. They are a perspective view (a) of a developing cartridge, a front view (b) of the developing cartridge, and a bottom view (c) of the developing cartridge. FIG. 5 is an explanatory diagram illustrating the relationship between the drum guide groove and development guide projection of the slot, the drum projection of the drum cartridge and the development groove of the development cartridge; FIG. 10 is an explanatory diagram illustrating a state in which the drum cartridge is mounted in the slot of the main body housing; FIG. 10 is an explanatory diagram illustrating a state in which the developing cartridge is attached to the slot of the main body housing; FIG. 10 is an explanatory diagram relating to a first modified example for explaining the relationship between the drum guide groove and development guide projections, and the drum projection and development groove; FIG. 10 is an explanatory diagram for explaining the relationship between the drum guide groove and the development guide projection, and the drum projection and the development groove, including an explanatory diagram (a) according to the second modified example and an explanatory diagram (b) according to the third modified example; , and an explanatory diagram (c) according to a fourth modified example. FIG. 10 is an explanatory diagram for explaining the relationship between the drum guide groove and the development guide projection, and the drum projection and the development groove; be.

Next, one embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the following description, first, the overall configuration of a color printer 1 as an example of an image forming apparatus will be described.
In the following description, the direction shown in FIG. 1 will be used. 1 is defined as "front", the right side of FIG. 1 is defined as "rear", the front side of FIG. 1 is defined as "right", and the back side of FIG. 1 is defined as "left". Moreover, the upper and lower sides of FIG. 1 are referred to as "up and down".

As shown in FIG. 1 , the color printer 1 includes a main housing 2 , a paper feed section 3 , an image forming section 4 and a paper discharge section 5 . The paper feeding section 3 supplies the paper P to the image forming section 4 . The image forming section 4 forms an image on the paper P. As shown in FIG. The paper discharge unit 5 discharges the paper P.

The paper feeding unit 3 is positioned at the bottom inside the main body housing 2 . The paper feed unit 3 includes a paper feed tray 31 and a paper feed mechanism 32 . The paper feed tray 31 is detachable from the main housing 2 . The paper feed mechanism 32 conveys the paper P from the paper feed tray 31 to the image forming section 4 .

The image forming section 4 includes four drum cartridges 40 , four developing cartridges 50 , an exposure device SU, a transfer unit 60 and a fixing unit 70 .
The image forming section 4 is inclined so that the four drum cartridges 40, the four developing cartridges 50, the exposure unit SU, and the transfer unit 60 are positioned downward from the front to the rear of the main housing 2. are placed.

Each drum cartridge 40 has a photosensitive drum 41, a charger (not shown), and a drum frame PF. The photosensitive drum 41 is rotatable about a first axis X1 extending in the first direction. The four drum cartridges 40 are arranged in a second direction orthogonal to the first direction while being attached to the main housing 2 .
In this embodiment, the image forming section 4 has four drum cartridges 40 . The four drum cartridges 40 correspond to black (K), yellow (Y), magenta (M), and cyan (C) toners. The four drum cartridges 40 are for black (K ), yellow (Y), magenta (M), and cyan (C).
In the following description, when specifying the drum cartridge 40 corresponding to the toner color, the symbols K, Y, M, and C are added after the reference numeral 40 corresponding to black, yellow, magenta, and cyan, respectively. I decided to.

Each developer cartridge 50 has a developer roller 51 and a developer frame DF. The development frame DF accommodates developer. The developing roller 51 is rotatable about a second axis X2 extending in the first direction. The four developer cartridges 50 are arranged in the second direction while being attached to the main housing 2 .
When the four drum cartridges 40 and the four developing cartridges 50 are attached to the main housing 2, the developing cartridges 50 are aligned with the drum cartridges 40 in the second direction.
In this embodiment, the image forming section 4 includes four developer cartridges 50 . The four developer cartridges 50 correspond to toners of respective colors of black (K), yellow (Y), magenta (M) and cyan (C). The four developing cartridges 50 are for black (K ), yellow (Y), magenta (M), and cyan (C).
In the following description, when specifying the developing cartridge 50 corresponding to the toner color, the symbols K, Y, M, and C are added after the reference numeral 50 corresponding to black, yellow, magenta, and cyan, respectively. I decided to.

An exposure unit SU is positioned below each drum cartridge 40 . The exposure unit SU emits laser light to each photosensitive drum 41 .

The transfer unit 60 is positioned between the four photosensitive drums 41 and the paper discharge tray 21 . 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 primary transfer roller 64 is positioned inside the intermediate transfer belt 63 . The intermediate transfer belt 63 is sandwiched between the primary transfer roller 64 and the photosensitive drum 41 .

The secondary transfer roller 65 is positioned outside the intermediate transfer belt 63 . The secondary transfer roller 65 and the driving roller 61 sandwich the intermediate transfer belt 63 .

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 .

The paper discharge section 5 is positioned above the main housing 2 . The paper discharge section 5 is positioned above the intermediate transfer belt 63 . The paper discharge section 5 includes a paper discharge roller 9 and a paper discharge tray 21 . The discharge roller 9 conveys the paper P toward the paper discharge tray 21 .

In the color printer 1 , the charger first charges the surface of the photosensitive drum 41 . 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 .

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

The developer image on the intermediate transfer belt 63 is transferred onto the paper P when the paper P passes between the intermediate transfer belt 63 and the secondary transfer roller 65 . After that, the developer image on the paper P is fixed by the fixing unit 70 . The paper P is then discharged to the paper discharge tray 21 by the discharge rollers 9 .

As shown in FIG. 2, the main housing 2 has an opening 22A, a slot 22B, and a cover C. As shown in FIG.
The opening 22A allows each drum cartridge 40 and each developer cartridge 50 to pass through when the drum cartridge 40 and developer cartridge 50 are attached or detached.

The slot 22B extends in the first direction from the opening 22A toward the inside of the main body housing 2 . The slot 22B is a space for accommodating four drum cartridges 40 and four developing cartridges 50. As shown in FIG.

The cover C is a member for opening and closing the opening 22A. The cover C rotates around the lower end of the cover C. As shown in FIG. The cover C is movable between an open position (position shown in FIG. 2) that opens the opening 22A and a closed position (not shown) that closes the opening 22A.
The cover C has a first protrusion C1 fitted in a drum slot 43 of each drum cartridge 40 (described later) and a second protrusion C2 fitted into a development slot 53 (described later) of each developer cartridge 50 .

The body housing 2 has a first protrusion D1 and a second protrusion D2 inside the side wall 2A. The first protrusions D1 are fitted into drum long holes 43 of each drum cartridge 40, which will be described later. The second protrusions D2 are fitted into development elongated holes 53 of each development cartridge 50, which will be described later. The side wall 2A is a side wall positioned apart from the cover C in the first direction when the cover C is in the closed position.
The first protrusion D1 and the second protrusion D2 face the first protrusion C1 and the second protrusion C2 of the cover C in the first direction when the cover C is in the closed position.
Further, the main housing 2 has a cartridge guide portion 2B at the bottom of the slot 22B.

The cartridge guide portion 2B has a drum guide groove 24 and a development guide projection 26. As shown in FIG. The drum guide groove 24 and the development guide protrusion 26 are positioned on the upper surface of the cartridge guide portion 2B. Four drum guide grooves 24 and four development guide projections 26 are arranged in the second direction (see also FIG. 5).
Further, the cartridge guide portion 2B has a through hole (not shown) through which the laser beam from the exposure unit SU passes.
As shown in FIG. 5, each drum guide groove 24 is a groove for guiding the drum cartridge 40 extending in the first direction. The width of the drum guide groove 24 in the second direction narrows from the opening 22A toward the side wall 2A (that is, the inside of the main housing 2). More specifically, the drum guide groove 24 has a tapered shape in which both opposing side surfaces forming the groove are symmetrically and continuously inclined. The four drum guide grooves 24K, 24Y, 24M and 24C have the same shape.
Each development guide projection 26 is a projection that extends in the first direction and guides the development cartridge 50 . The width of the development guide protrusion 26 in the second direction increases from the opening 22A toward the side wall 2A (that is, the inside of the main housing 2). More specifically, the development guide protrusion 26 has a tapered shape in which the opposite side surfaces forming the protrusion are symmetrically and continuously inclined. The four development guide projections 26K, 26Y, 26M and 26C have the same shape.
Further, as shown in FIG. 2, the upper surface of the cartridge guide portion 2B is inclined upward so as to approach the intermediate transfer belt 63 from the opening 22A toward the side wall 2A (that is, the inside of the main housing 2).

As shown in FIG. 5, the upper surface of the cartridge guide portion 2B has a drum guide surface 25 and a development guide surface 27. As shown in FIG.
The drum guide surfaces 25 are positioned on both sides of the drum guide groove 24 . The drum guide surface 25 is a surface for guiding the drum cartridge 40, and is aligned with the drum guide groove 24 in the second direction.
As described above, the upper surface of the cartridge guide portion 2B is inclined so as to approach the intermediate transfer belt 63. As shown in FIG. Therefore, the drum guide surface 25 is inclined so as to approach the intermediate transfer belt 63 from the opening 22A toward the interior of the main housing 2 .
The development guide surface 27 is positioned on both sides of the development guide protrusion 26 . The development guide surface 27 is a surface for guiding the development cartridge 50, and is aligned with the development guide protrusion 26 in the second direction.
As described above, the upper surface of the cartridge guide portion 2B is inclined so as to approach the intermediate transfer belt 63. As shown in FIG. Therefore, the development guide surface 27 is inclined so as to approach the intermediate transfer belt 63 from the opening 22A toward the interior of the main housing 2 .
Incidentally, as shown in FIG. 6, the bottom surface 24A of the drum guide groove 24 is parallel to the lower surface of the intermediate transfer belt 63. As shown in FIG. On the other hand, the drum guide surface 25 is inclined with respect to the lower surface of the intermediate transfer belt 63 .
Similarly, as shown in FIG. 7, the upper surface 26A of the development guide protrusion 26 is parallel to the lower surface of the intermediate transfer belt 63. As shown in FIG. On the other hand, the development guide surface 27 is inclined with respect to the lower surface of the intermediate transfer belt 63 .

The drum cartridge 40 and the developing cartridge 50 are each independently attachable to and detachable from the main housing 2 in the first direction.
Specifically, each drum cartridge 40 can be mounted in the slot 22B through the opening 22A in the first direction. Similarly, each developer cartridge 50 can be mounted in the slot 22B through the opening 22A in the first direction.
The four drum cartridges 40 have the same structure. The four developer cartridges 50 have the same structure.

As shown in FIG. 3, the drum frame PF of the drum cartridge 40 includes a first drum side wall PF1 and a second drum side wall PF2 facing each other in the first direction when the drum cartridge 40 is mounted in the slot 22B. It has a third drum sidewall PF3 and a fourth drum sidewall PF4 corresponding in direction, and a fifth drum sidewall PF5 forming a bottom surface.
The first drum side wall PF1 is a side wall positioned near the opening 22A when the drum cartridge 40 is mounted in the slot 22B. The first drum side wall PF1 has a drum oblong hole 43 into which the first protrusion C1 of the cover C is fitted when the cover C is moved to the closed position.
The second drum side wall PF2 is a side wall positioned far from the opening 22A when the drum cartridge 40 is attached to the main body housing 2 . The second drum side wall PF2 has a drum oblong hole into which the first protrusion D1 of the main housing 2 is fitted. Since this drum slot has the same shape as the drum slot 43, illustration is omitted.
The first drum side wall PF1 and the second drum side wall PF2 rotatably support the photosensitive drum 41 .
A third drum sidewall PF3 and a fourth drum sidewall PF4 connect the first drum sidewall PF1 and the second drum sidewall PF2, respectively.

The fifth drum side wall PF5 connects the first drum side wall PF1, the second drum side wall PF2, the third drum side wall PF3 and the fourth drum side wall PF4.
The fifth drum side wall PF5 has a drum contact surface 45 that contacts the drum guide surface 25 when the drum cartridge 40 is mounted in the slot 22B. More specifically, when the drum cartridge 40 is installed in the slot 22B, the drum contact surface 45 is inclined toward the intermediate transfer belt 63 from the opening 22A toward the inside of the main housing 2 (Fig. 6). The inclination angle of the drum contact surface 45 with respect to the first axis X1 of the photosensitive drum 41 is equal to the inclination angle of the drum guide surface 25 with respect to the lower surface of the intermediate transfer belt 63 . Therefore, when the drum cartridge 40 is installed in the slot 22B, the drum guide surface 25 and the drum contact surface 45 are in contact with each other, and the photosensitive drum 41 and the intermediate transfer belt 63 are parallel.
Further, the fifth drum side wall PF5 has a drum projection 46 projecting from the drum contact surface 45. As shown in FIG. The drum projection 46 extends in the first direction and fits into the drum guide groove 24 . The width of the drum projection 46 in the second direction narrows from the opening 22A toward the inside of the main housing 2 when the drum cartridge 40 is installed in the slot 22B. More specifically, the drum protrusion 46 has a tapered shape in which the opposite sides forming the protrusion are symmetrically and continuously inclined. Both side surfaces of the drum protrusion 46 contact both side walls of the drum guide groove 24 when the drum cartridge 40 is mounted in the slot 22B.
As shown in FIG. 3, the lower surface of the drum protrusion 46 is parallel to the first axis X1 of the photosensitive drum 41, while the drum contact surface 45 is parallel to the first axis X1 of the photosensitive drum 41. Inclined. More specifically, the drum contact surface 45 is slanted upward from the opening 22A toward the inside of the main housing 2 when the drum cartridge 40 is installed in the slot 22B.

As shown in FIG. 4, the development frame DF of the development cartridge 50 includes a first development side wall DF1 and a second development side wall DF2 facing each other in the first direction when the development cartridge 50 is mounted in the slot 22B, and a second development side wall DF2. It has a third developing sidewall DF3 and a fourth developing sidewall DF4 corresponding in direction, and a fifth developing sidewall DF5 forming a bottom surface.
The first developing side wall DF1 is a side wall positioned near the opening 22A when the developing cartridge 50 is installed in the slot 22B. The first developing side wall DF1 has a developing oblong hole 53 into which the second projection C2 of the cover C is fitted when the cover C is moved to the closed position.
The second developing side wall DF2 is a side wall positioned far from the opening 22A when the developing cartridge 50 is installed in the slot 22B. The second development side wall DF2 has a development slot into which the second protrusion D2 of the main body housing 2 is fitted. Since this development slot has the same shape as the development slot 53, illustration is omitted.
The first developing side wall DF1 and the second developing side wall DF2 rotatably support the developing roller 51 .
A third development sidewall DF3 and a fourth development sidewall DF4 connect the first development sidewall DF1 and the second development sidewall DF2, respectively.

The fifth development sidewall DF5 connects the first development sidewall DF1, the second development sidewall DF2, the third development sidewall DF3 and the fourth development sidewall DF4.
The fifth development side wall DF5 has a development contact surface 55 that contacts the development guide surface 27 when the development cartridge 50 is mounted in the slot 22B. More specifically, when the developer cartridge 50 is attached to the body housing 2, the development contact surface 55 is inclined so as to approach the intermediate transfer belt 63 from the opening 22A toward the inside of the body housing 2. (See FIG. 7). The inclination angle of the development contact surface 55 with respect to the second axis X2 of the development roller 51 is equal to the inclination angle of the development guide surface 27 with respect to the lower surface of the intermediate transfer belt 63 . Therefore, when the developer cartridge 50 is installed in the slot 22B, the developer guide surface 27 and the developer contact surface 55 are in contact with each other, and the developer roller 51 and the intermediate transfer belt 63 are parallel.
Further, the fifth development side wall DF5 has a development groove 56 of the development contact surface 55. As shown in FIG. The development groove 56 extends in the first direction and fits into the development guide projection 26 when the development cartridge 50 is mounted in the slot 22B. The width of the developing groove 56 in the second direction increases from the opening 22A toward the inside of the main housing 2 when the developing cartridge 50 is installed in the slot 22B. More specifically, the development groove 56 has a tapered shape in which the opposing side surfaces on both sides forming the groove are symmetrically and continuously inclined. Both side surfaces of the development groove 56 are in contact with both side walls of the development guide projection 26 when the development cartridge 50 is installed in the slot 22B.
As shown in FIG. 4, the upper surface of the developing groove 56 is parallel to the second axis X2 of the developing roller 51, whereas the developing contact surface 55 is parallel to the second axis X2 of the developing roller 51. Inclined. More specifically, the developer contact surface 55 is inclined upward from the opening 22A toward the interior of the main body housing 2 when the developer cartridge 50 is installed in the slot 22B.

Next, a procedure for mounting the drum cartridge 40 and the developing cartridge 50 in the slot 22B of the main housing 2 will be described with reference to FIGS. 6 and 7. FIG.
As shown in FIGS. 2 and 6, when mounting the drum cartridge 40 in the slot 22B, the opening 22A and the slot 22B are exposed by moving the cover C to the open position. Then, after inserting the tip of the drum projection 46 into the drum guide groove 24 of the cartridge guide portion 2B, the drum cartridge 40 is inserted in the first direction, and the drum cartridge 40 is attached to the main housing 2 . At this time, since the width of the drum guide groove 24 on the opening 22A side is larger than the width of the drum projection 46 on the leading end side in the mounting direction, the drum cartridge 40 can be easily mounted in the slot 22B.
When the tip of the drum protrusion 46 is inserted into the drum guide groove 24 , the drum contact surface 45 comes into contact with the drum guide surface 25 . As the drum cartridge 40 is inserted in the first direction, the tip of the drum protrusion 46 is guided by the gradually narrowing drum guide groove 24 , so that the drum cartridge 40 can be accurately positioned within the main body housing 2 . installed in the correct position.

According to such a configuration, by inserting the drum cartridge 40 into the drum guide groove 24 from the side of the second drum side wall PF2, the narrow end of the drum protrusion 46 in the second direction is inserted first, and the drum The wide end of projection 46 will be inserted last. On the other hand, the width in the second direction of the drum guide groove 24 into which the drum projection 46 is fitted is the widest on the side of the opening 22A and the narrowest on the side of the side wall 2A. Therefore, the drum cartridge 40 is easily attached to the main housing 2 due to the large dimensional difference on the inlet (opening 22A) side.
Further, since the distance between the drum guide surface 25 and the intermediate transfer belt 63 becomes large on the inlet (opening 22A) side, when the drum cartridge 40 is mounted, the photosensitive drum 41 and the intermediate transfer belt 63 come into contact with each other and the surface of the photosensitive drum 41 is displaced. can be prevented from being damaged. That is, when mounting the drum cartridge 40 in the slot 22</b>B, the drum cartridge 40 can be inserted from a position where it is unlikely to hit the intermediate transfer belt 63 .

As shown in FIGS. 2 and 7, when mounting the developer cartridge 50 in the slot 22B, the opening 22A and the slot 22B are exposed by moving the cover C to the open position. Then, after inserting the tip of the developing groove 56 into the developing guide projection 26 of the cartridge guide portion 2B, the developing cartridge 50 is attached to the main housing 2 by inserting the drum cartridge 40 in the first direction. At this time, since the width of the development guide protrusion 26 on the opening 22A side is smaller than the width of the development groove 56 on the front end side in the mounting direction, the development cartridge 50 can be easily mounted in the slot 22B.
When the tip of the development groove 56 is inserted into the development guide projection 26 , the development contact surface 55 comes into contact with the development guide surface 27 . As the developer cartridge 50 is inserted in the first direction, the tip of the developer groove 56 is guided by the developer guide protrusion 26 that gradually widens, so that the developer cartridge 50 can be accurately inserted into the main body housing 2 . installed in the correct position.

According to such a configuration, by inserting the developing cartridge 50 into the drum guide groove 24 from the side of the second developing side wall DF2, the wide end of the developing groove 56 in the second direction is inserted first, and the developing groove 56 is inserted first. The narrow end of groove 56 will be inserted last. On the other hand, the development guide protrusion 26 into which the development groove 56 is fitted has the narrowest width in the second direction on the opening 22A side and the widest on the side wall 2A side. Therefore, the developing cartridge 50 is easily attached to the main housing 2 due to the large dimensional difference on the inlet (opening 22A) side.
Further, since the distance between the development guide surface 27 and the intermediate transfer belt 63 becomes large on the entrance (opening 22A) side, when the developing cartridge 50 is mounted, the developing roller 51 and the intermediate transfer belt 63 come into contact with each other and the surface of the developing roller 51 is displaced. can be prevented from being damaged. That is, when the developer cartridge 50 is installed in the slot 22B, the developer cartridge 50 can be inserted from a position where it is difficult to hit the intermediate transfer belt 63 .

When the drum cartridge 40 is attached to the slot 22B, the first protrusion D1 of the side wall 2A of the main body housing 2 fits into the drum oblong hole of the second drum side wall PF2 of the drum cartridge 40. As shown in FIG.
When the developer cartridge 50 is attached to the slot 22B, the second projection D2 of the side wall 2A of the main body housing 2 fits into the development slot of the second developer side wall DF2 of the developer cartridge 50. As shown in FIG.
Then, when the cover C is moved to the closed position, the first projection C1 of the cover C fits into the drum elongated hole 43 of the first drum side wall PF1 of the drum cartridge 40, and the second projection C2 of the cover C becomes the first projection C2 of the developing cartridge 50. It fits into the development slot 53 of the development side wall DF1.
When the drum pressing member 80 (see FIG. 1) is lifted in this state, the drum cartridge 40 is lifted and the photosensitive drum 41 contacts the intermediate transfer belt 63 . Further, when the developing pressing member (not shown) is lifted, the developing cartridge 50 is lifted and the developing roller 51 comes into contact with the photosensitive drum 41 at a predetermined position.

According to the above, the following effects can be obtained in this embodiment.
Since the width of the drum guide groove 24 on the opening 22A side is larger than the width of the drum protrusion 46 on the front end side in the mounting direction, the drum cartridge 40 can be easily mounted in the slot 22B.

The drum guide groove 24 of the main body housing 2 has a tapered shape, and the corresponding drum protrusion 46 of the drum cartridge 40 has a tapered shape, so that the drum cartridge 40 can be more smoothly mounted in the slot 22B. .

Since the width of the opening side 22A of the development guide projection 26 is smaller than the width of the development groove 56 on the leading end side in the mounting direction, the development cartridge 50 can be easily mounted in the slot 22B.

Since the development guide protrusion 26 of the main body housing 2 has a tapered shape and the corresponding development groove 56 of the development cartridge 50 has a tapered shape, the development cartridge 50 can be more smoothly mounted in the slot 22B. .

Since the distance between the drum guide surface 25 and the intermediate transfer belt 63 increases on the side of the opening 22A of the main body housing 2, when the drum cartridge 40 is installed in the slot 22B, the photosensitive drum 41 does not easily hit the intermediate transfer belt 63. A cartridge 40 can be inserted.

Since the distance between the development guide surface 27 and the intermediate transfer belt 63 increases on the side of the opening 22A of the main body housing 2, when the developer cartridge 50 is installed in the slot 22B, the developer cartridge 50 is inserted from a position where it is difficult to hit the intermediate transfer belt 63. can do.

Since the first protrusion D1 and the second protrusion D2 of the side wall 2A of the main body housing 2 are fitted into the drum slot of the drum cartridge 40 and the development slot of the development cartridge 50, respectively, the drum cartridge 40 and the development cartridge 50 are intermediately transferred. It can be brought into contact with and separated from the belt 63 .

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. The specific configuration can be changed as appropriate without departing from the gist of the present invention.

Although the drum guide groove 24 and the development guide protrusion 26 are positioned on the upper surface of the cartridge guide portion 2B in the above embodiment, the present invention is not limited to such a configuration.
For example, the body housing 2 may have a drum guide projection instead of the drum guide groove 24 and a development guide groove instead of the development guide projection 26 . In this case, the drum cartridge 40 has a drum groove that extends in the first direction and into which the drum guide projection is fitted when the drum cartridge 40 is mounted in the slot 22B. Similarly, the developer cartridge 50 has a developer projection that extends in the first direction and fits into the developer guide groove when the developer cartridge 50 is installed in the slot 22B.
When the body housing 2 has drum guide projections, the width of the drum guide projections in the second direction increases toward the inside of the body housing 2 from the opening 22A. The width of the drum groove of the drum cartridge 40 in the second direction increases toward the inside of the main housing 2 from the opening 22A in the state where the drum cartridge 40 is mounted in the slot 22B.
Further, when the main body housing 2 has the development guide groove, the width of the development guide groove in the second direction becomes narrower from the opening 22A toward the inside of the main body housing 2 . The width of the developing projection of the developing cartridge 50 in the second direction becomes narrower from the opening 22A toward the inside of the main housing 2 when the developing cartridge 50 is installed in the slot 22B.

Further, the main body housing 2 may have a drum guide groove and a development guide groove, the drum cartridge 40 may have a drum projection, and the development cartridge 50 may have a development projection.
Similarly, the body housing 2 may have a drum guide projection and a development guide projection, the drum cartridge 40 may have a drum groove, and the development cartridge 50 may have a development groove.
Furthermore, the body housing 2 may be configured to have a drum guide groove and a drum guide projection, and a development guide groove and a development guide projection.

In the above-described embodiment, the drum guide surface 25 and the development guide surface 27 on the upper surface of the cartridge guide portion 2B are inclined so as to approach the intermediate transfer belt 63 from the opening 22A toward the inside of the main housing 2. The invention is not limited to such configurations.
The drum guide surface 25 and the development guide surface 27 can also be configured so as not to be inclined so as to approach the intermediate transfer belt 63 from the opening 22A toward the inside of the main housing 2 . For example, the drum guide surface 25 and the development guide surface 27 can be configured parallel to the lower surface of the intermediate transfer belt 63 . In this case, the drum contact surface 45 of the drum cartridge 40 is parallel to the first axis X1 of the photosensitive drum 41, and the development contact surface 55 of the developing cartridge 50 is parallel to the second axis X2 of the developing roller 51.

In the above embodiment, the side wall 2A of the main housing 2 has the first protrusion D1 and the second protrusion D2, and the cover C has the first protrusion C1 and the second protrusion C2. Not limited.
For example, the side wall 2A of the main housing 2 may have a first elongated hole instead of the first protrusion D1, and a second elongated hole instead of the second protrusion D2. In this case, the drum cartridge 40 has a drum protrusion that fits into the first long hole when the drum cartridge 40 is attached to the main housing 2 . Similarly, the developer cartridge 50 has a developer projection that fits into the second elongated hole when the developer cartridge 50 is attached to the main housing 2 .
Similarly, in the cover C, the first projection C1 and the first long hole, and the second projection C2 and the second long hole may be exchanged. In this case, the drum cartridge 40 has a drum projection, and the developer cartridge 50 has a developer projection. Also, different combinations can be used for the entrance (opening 22A) side and the back (side wall 2A) side.

In the above-described embodiment, the four drum guide grooves 24 of the main housing 2 have the same shape, and the four development guide projections 26 have the same shape. The four drum cartridges 40 and the four developing cartridges 50 have the same shape. However, the invention is not limited to such a configuration.
For example, developer cartridge 50 may include four developer cartridges, each having a different width of developer groove or developer protrusion. On the other hand, the drum cartridge 40 may include four drum cartridges, each having drum projections or drum grooves of the same width.

More specifically, as shown in the first modification of FIG. 8, the developer cartridge 50 includes four developer cartridges 50K, 50Y, 50M and 50C. Of these, for example, the black developing cartridge 50K is the first developing cartridge that contains the developer of the first color. The other developing cartridges 50Y, 50M, and 50C are second developing cartridges containing developer of a second color different from the first color.
As shown in FIG. 8, the width of the developing groove 56 of the developing cartridge 50K is wider than the width of the developing groove 56 of the developing cartridge 50Y, the developing groove 56 of the developing cartridge 50M, and the developing groove 56 of the developing cartridge 50C. Specifically, the width of the developing cartridge 50K on the front end side in the mounting direction is wider than the widths on the front end side of the mounting direction of the other developing cartridges 50Y, 50M, and 50C. The widths of the developing grooves 56 of the developing cartridges 50Y, 50M, and 50C may be different for each toner color.

On the other hand, the drum cartridge 40 includes four drum cartridges 40K, 40Y, 40M and 40C. Of these, the black drum cartridge 40K is the first drum cartridge corresponding to the first developing cartridge. Other drum cartridges 40Y, 40M, and 40C are second drum cartridges corresponding to the second developing cartridges.
The lengths (widths) of the drum projections 46 of the drum cartridge 40 in the second direction are all the same regardless of the color of the toner. Specifically, the widths of the developing cartridges 50K, 50Y, 50M, and 50C on the leading end side in the mounting direction are all equal.

The main housing 2 has a first drum guide groove 24K that guides the drum cartridge 40K for black, a second drum guide groove 24Y that guides the drum cartridge 40Y for yellow, and a drum for magenta. It has a second drum guide groove 24M for guiding the cartridge 40M and a second drum guide groove 24C for guiding the cyan drum cartridge 40C. The length of the first drum guide groove 24K in the second direction is the same as the length of the second drum guide grooves 24Y, 24M and 24C in the second direction. Specifically, the first drum guide groove 24K and the second drum guide grooves 24Y, 24M, and 24C all have the same width on the opening 22A side.
The main housing 2 also has a first development guide projection 26K that guides the black development cartridge 50K, a second development guide projection 26Y that guides the yellow development cartridge 50Y, and a magenta development guide projection 26Y that guides the yellow development cartridge 50Y. a second development guide projection 26M for guiding the development cartridge 50M for cyan, and a second development guide projection 26C for guiding the development cartridge 50C for cyan. The widths of the first development guide projection 26K and the second development guide projections 26Y, 26M, 26C are different corresponding to the width of the development groove 56 of each development cartridge 50. As shown in FIG. That is, the length of the first development guide projection 26K in the second direction is different from the length of the second development guide projections 26Y, 26M, 26C in the second direction. Specifically, the width of the first development guide protrusion 26K on the opening 22A side is wider than the width of the second development guide protrusions 26Y, 26M, and 26C on the opening 22A side.

According to the configuration of the first modified example described above, the widths of the developing grooves 56 in the second direction are different corresponding to the different colors of the developing cartridges 50, so that the wrong insertion of the developing cartridges 50 can be prevented.
In addition, since the common drum cartridge 40 can be used for a plurality of developing cartridges 50, the manufacturing cost can be reduced.

In the configuration of the first modified example described above, the main body housing 2 has first drum guide projections and second drum guide projections instead of the first drum guide groove 24K and the second drum guide grooves 24Y, 24M, and 24C. can also be configured. Further, the body housing 2 can be configured to have a first development guide groove and a second development guide groove instead of the first development guide projection 26K and the second development guide projections 26Y, 26M, and 26C.
In this case, the first drum cartridge 40K has a first drum groove that extends in the first direction and into which the first drum guide protrusion is fitted when it is mounted in the slot 22B, and the second drum cartridges 40Y, 40M, and 40C , and has a second drum groove extending in the first direction and into which the second drum guide projection is fitted when it is mounted in the slot 22B.
Similarly, the first developer cartridge 50K has a first developer projection extending in the first direction and fitted in the first developer guide groove when mounted in the slot 22B, and the second developer cartridges 50Y, 50M, 50 , and has a second developing protrusion extending in the first direction and fitted in the second developing guide groove when the developer is mounted in the slot 22B.
The length of the first drum guide projection in the second direction is the same as the length of the second drum guide projection in the second direction. Also, the length of the first development guide groove in the second direction is different from the length of the second development guide groove in the second direction.

The second to sixth modifications will be described below with reference to FIGS. 9 and 10. FIG. In the following description, the same reference numerals are given to the same constituent elements as in the above-described embodiment, and detailed description thereof will be omitted.

As shown in FIG. 9A, in the configuration of the second modified example, the main housing 2 has a drum guide groove 124 and a development guide protrusion 126 on the upper surface of the cartridge guide portion 2B.
The width of the drum guide groove 124 in the second direction tapers toward the inside of the main housing 2 from the opening 22A to the middle of the side wall 2A, and then has a constant width.
The width of the development guide projection 126 in the second direction tapers toward the inside of the main housing 2 from the opening 22A to the middle of the side wall 2A, and then has a constant width.
The drum cartridge 40 has a drum protrusion 146 corresponding to the shape of the drum guide groove 124 . The developer cartridge 50 has a developer groove 156 corresponding to the shape of the developer guide protrusion 126 .
Even with such a configuration, the drum cartridge 40 and the developing cartridge 50 are easily attached to the main housing 2 due to the large dimensional difference on the entrance (opening 22A) side.

As shown in FIG. 9B, in the configuration of the third modification, the main body housing 2 has the drum guide groove 124 and the development guide protrusion 126 similar to those of the second modification.
On the other hand, the drum protrusion 246 of the drum cartridge 40 has a constant width corresponding to the width of the straight portion of the drum guide groove 124 . The development groove 256 of the development cartridge 50 has a constant width corresponding to the width of the linear portion of the development guide protrusion 126 .
Even with such a configuration, the drum cartridge 40 and the developing cartridge 50 can be easily attached to the main housing 2 due to the large dimensional difference on the inlet side.

As shown in FIG. 9C, in the configuration of the fourth modification, the main body housing 2 has a drum guide groove 324 and a development guide protrusion 326 on the upper surface of the cartridge guide portion 2B.
The width of the drum guide groove 324 in the second direction narrows stepwise from the opening 22A to the side wall 2A toward the interior of the main body housing 2 .
The width of the development guide projection 326 in the second direction widens stepwise toward the inside of the main housing 2 from the opening 22A to the side wall 2A.
The drum cartridge 40 has a drum protrusion 346 corresponding to the shape of the drum guide groove 324 . The developer cartridge 50 has a developer groove 356 corresponding to the shape of the developer guide protrusion 326 .
Even with such a configuration, the drum cartridge 40 and the developing cartridge 50 can be easily attached to the main housing 2 due to the large dimensional difference on the inlet side.

As shown in FIG. 10A, in the configuration of the fifth modification, the main body housing 2 has a drum guide groove 424 and a development guide projection 426 on the upper surface of the cartridge guide portion 2B.
The width of the drum guide groove 424 in the second direction is constant from the opening 22A to the side wall 2A.
Similarly, the width of the development guide projection 426 in the second direction is constant from the opening 22A to the side wall 2A.
In the drum cartridge 40, the width of the drum protrusion 446 in the second direction has a constant width corresponding to the width of the drum guide groove 424 from the opening 22A to the middle of the side wall 2A, and then toward the side wall 2A. It becomes narrower in a tapered shape.
In the developing cartridge 50, the width of the developing groove 456 in the second direction has a constant width corresponding to the width of the developing guide projection 426 from the opening 22A to the middle of the side wall 2A, and then tapers toward the side wall 2A. It is wide in shape.
Even with such a configuration, the drum cartridge 40 and the developing cartridge 50 can be easily attached to the main housing 2 due to the large dimensional difference on the inlet side.

As shown in FIG. 10B, in the configuration of the sixth modification, the main body housing 2 has a drum guide groove 524 and a development guide projection 526 on the upper surface of the cartridge guide portion 2B.
The width of the drum guide groove 524 in the second direction tapers toward the interior of the main housing 2 from the opening 22A and the side wall 2A, and has a constant width at the central portion.
On the other hand, the width of the development guide protrusion 526 in the second direction is constant from the opening 22A to the side wall 2A.
The drum projection 546 of the drum cartridge 40 has a constant width from the opening 22A to the side wall 2A.
The developing groove 556 of the developing cartridge 50 narrows in a tapered shape from the opening 22A and the side wall 2A toward the inside of the main body housing 2, and the central portion has a constant width corresponding to the width of the developing guide projection 526. .
Even with such a configuration, the drum cartridge 40 and the developing cartridge 50 can be easily attached to the main housing 2 due to the large dimensional difference on the inlet side.

Although the present invention is applied to the color printer 1 in the above-described embodiment and modifications, the present invention is not limited to this, and can be applied to other image forming apparatuses such as monochrome printers, copiers, multi-function machines, and the like. may apply.

Each element described in the above embodiment and modifications may be implemented in any combination.

Reference Signs List 1 color printer 2 main housing 22A opening 22B slot 24 drum guide groove 26 development guide projection 40 drum cartridge 41 photosensitive drum 46 drum projection 50 development cartridge 51 development roller 56 development groove

Claims (13)

a body housing having an opening, the body housing having a slot extending in a first direction from the opening toward the inside of the body housing;
a drum cartridge having a photosensitive drum rotatable about a first axis extending in the first direction, the drum cartridge being mountable in the slot through the opening in the first direction;
A developing cartridge having a developing roller rotatable about a second axis extending in the first direction, the developing cartridge being mountable in the slot through the opening in the first direction, the drum cartridge and the developing device a developer cartridge aligned with the drum cartridge in a second direction intersecting the first direction when the cartridge is mounted in the slot,
the body housing has a development guide groove extending in the first direction for guiding the development cartridge;
The developer cartridge has a developer protrusion extending in the first direction and fitted into the developer guide groove,
The image forming apparatus, wherein the width of the developing guide groove in the second direction narrows from the opening toward the inside of the main housing. 2. The method according to claim 1, wherein the width of the developing projection in the second direction becomes narrower from the opening toward the inside of the main housing when the developing cartridge is mounted in the slot. Image forming device. The developer cartridge includes a first developer cartridge containing a developer of a first color and a second developer cartridge containing a developer of a second color different from the first color,
The development guide groove is
including a first development guide groove for guiding the first development cartridge and a second development guide groove for guiding the second development cartridge;
3. The image forming apparatus according to claim 1, wherein the length of the first development guide groove in the second direction is different from the length of the second development guide groove in the second direction. . the body housing has a drum guide groove extending in the first direction for guiding the drum cartridge;
4. The image forming apparatus according to claim 1, wherein the drum cartridge has a drum protrusion extending in the first direction and fitted in the drum guide groove. 5. An image forming apparatus according to claim 4, wherein said drum guide groove has a tapered shape. 6. An image forming apparatus according to claim 4, wherein said drum protrusion has a tapered shape. The developer cartridge includes a first developer cartridge containing a developer of a first color and a second developer cartridge containing a developer of a second color different from the first color,
The drum cartridge includes a first drum cartridge corresponding to the first developing cartridge and a second drum cartridge corresponding to the second developing cartridge,
The drum guide groove is
a first drum guide groove that guides the first drum cartridge; and a second drum guide groove that guides the second drum cartridge;
7. The length of the first drum guide groove in the second direction is the same as the length of the second drum guide groove in the second direction. The image forming apparatus according to . The main body housing is
a cover for opening and closing the opening;
a side wall positioned apart from the cover in the first direction when the cover is in the closed position;
The side walls are
having a first projection,
The drum cartridge is
8. The image forming apparatus according to claim 1, further comprising a drum elongated hole into which said first protrusion is fitted when said drum cartridge is attached to said main body housing. The main body housing is
a cover that opens and closes the opening;
a side wall positioned apart from the cover in the first direction when the cover is in the closed position;
The side walls are
having a first oblong hole,
The drum cartridge is
8. The image forming apparatus according to any one of claims 1 to 7, further comprising a drum projection that fits into the first long hole when the drum cartridge is attached to the main housing. The side walls are
having a second projection,
The developing cartridge is
10. The image forming apparatus according to claim 9, further comprising a developing elongated hole into which said second protrusion is fitted when said developing cartridge is mounted in said main housing. The side walls are
having a second oblong hole,
The developing cartridge is
11. The image forming apparatus according to claim 9, further comprising a developing protrusion that fits into the second elongated hole when the developing cartridge is attached to the main housing. 12. An intermediate transfer belt positioned above the drum cartridge and the developing cartridge when the drum cartridge and the developing cartridge are attached to the main housing. The image forming apparatus according to any one of items 1 to 3. 13. The image forming apparatus according to claim 12, further comprising a paper discharge section positioned above the intermediate transfer belt.

Images