Image forming apparatus

Abstract

To provide a new form of an image forming apparatus including a pump unit.SOLUTION: An image forming apparatus comprises: an apparatus body; a first toner container that stores first toner and is removably supported on the apparatus body, the first toner container configured to be capable of supplying the first toner to a first developer container with air; a second toner container that stores second toner and is removably supported on the apparatus body, the second toner container configured to be capable of supplying the second toner to a second developer container with air, and being aligned with the first toner container in a first direction; and a pump unit that has a first pump for conveying the air to the first toner container, and a second pump for conveying the air to the second toner container. The first pump and the second pump are actuated by one driving source, and are aligned in the first direction.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus including a pump unit. [Background technology]

[0002] Conventionally, an image forming apparatus has been proposed that incorporates a cartridge equipped with a developer container that stores toner and an attachment portion to which a refill pack that stores toner can be attached (see Patent Document 1). Toner discharged from the refill pack attached to the attachment portion is temporarily stored in a reserve tank provided in the cartridge, and then transported from the reserve tank to the developer container. The toner is transported from the reserve tank to the developer container by air flowing using a screw or pump. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-134401 Summary of the Invention [Problem to be solved by the invention]

[0004] SUMMARY OF THE INVENTION An object of the present invention is to provide a new embodiment of an image forming apparatus including a pump unit. [Means for solving the problem]

[0005] The present invention provides an image forming apparatus for forming an image on a sheet, the apparatus comprising: an apparatus main body having a first developing unit having a first developing container configured to store a first toner and a first developing roller that carries the first toner; a second developing unit having a second developing container configured to store a second toner and a second developing roller that carries the second toner; a first toner container that stores the first toner and is detachably supported by the apparatus main body, the first toner container being configured to be able to replenish the first toner together with air to the first developing container; a second toner container that stores the second toner and is detachably supported by the apparatus main body, the second toner container being configured to be able to replenish the second toner together with air to the second developing container, the second toner container being aligned with the first toner container in a first direction; and a pump unit having a first pump for transporting air to the first toner container and a second pump for transporting air to the second toner container, the first pump and the second pump being operated by a single driving source and aligned in the first direction.

[0006] The present invention also provides an image forming apparatus for forming an image on a sheet, the image forming apparatus comprising: an apparatus main body having a first developing unit including a first developing container configured to contain a first toner and a first developing roller that carries the first toner; a second developing unit including a second developing container configured to contain a second toner and a second developing roller that carries the second toner; a first toner container that contains the first toner and is detachably supported by the apparatus main body, the first toner container being configured to be able to replenish the first toner together with air to the first developing container; and a second toner container that contains the second toner and is detachably supported by the apparatus main body, the second toner being replenished together with air to the first developing container. and a pump unit configured to be able to replenish a second developing container, the pump unit having a second toner container aligned with the first toner container in a first direction, a first pump for transporting air to the first toner container, and a second pump for transporting air to the second toner container, wherein the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction, the first toner container and the second toner container are positioned closer to the first developing unit than the second developing unit in the second direction, and the pump unit is positioned so as to overlap with the first developing unit when viewed in a third direction perpendicular to both the first direction and the second direction. [Effects of the Invention]

[0007] According to the present invention, a new embodiment of an image forming apparatus including a pump unit can be provided. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram illustrating an entire image forming apparatus according to an embodiment of the present invention. [Figure 2] 1A is a perspective view showing an image forming apparatus, FIG. 1B is a perspective view showing an image forming apparatus with a front door open, and FIG. 1C is a perspective view showing an image forming apparatus with a toner cartridge removed. [Figure 3]FIG. 4A is a perspective view showing an image forming unit, and FIG. 4B is a perspective view showing the image forming unit with a toner cartridge removed. [Figure 4] FIG. 2A is a plan view showing a laser scanner and an image forming unit, and FIG. 2B is a plan view showing the image forming unit. [Figure 5] 5A is a cross-sectional view showing the cross section 5A-5A in FIG. 4A, and FIG. 5B is a cross-sectional view showing the cross section 5B-5B in FIG. 4A. [Figure 6] FIG. [Figure 7] FIG. [Figure 8] (a) is a front view of the toner cartridge, (b) is a plan view of the toner cartridge, (c) is a bottom view of the toner cartridge, (d) is a side view of the toner cartridge, and (e) is a rear view of the toner cartridge. [Figure 9] 8(e) is a cross-sectional view showing the 9A-9A cross section, FIG. 8(b) is a perspective view showing the toner cartridge cut along the XZ plane, and FIG. 8(c) is an exploded view showing the toner cartridge cut along the XZ plane. [Figure 10] 8A is a cross-sectional view showing the cross section taken along line 10A-10A in FIG. 8B, and FIG. 8B is a perspective view showing the toner cartridge cut along the YZ plane. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Overall structure] The image forming apparatus 100 according to this embodiment is an electrophotographic laser beam printer. The image forming apparatus includes printers, copiers, facsimiles, and multifunction peripherals, and refers to an apparatus that forms an image on a sheet used as a recording medium based on image information input from an external PC or image information read from an original. In addition to the main body having an image forming function, an image forming apparatus may be connected to accessory devices such as an optional feeder, an image reader, and a sheet processing device, and the entire system connected to such accessory devices is also considered a type of image forming apparatus.

[0010] As shown in Fig. 1, the image forming apparatus 100 has an image forming section 40 that forms an image on a sheet S, a feeding unit 18, a fixing unit 21, and a pair of discharge rollers 22. The image forming section 40 has four process cartridges PY, PM, PC, and PK that form toner images of four colors, yellow (Y), magenta (M), cyan (C), and black (K), respectively, and a laser scanner LB. The laser scanner LB, which serves as an exposure unit, is disposed above the process cartridges PY, PM, PC, and PK. Note that an LED exposure unit may be used instead of the laser scanner LB.

[0011] The image forming apparatus 100 excluding the process cartridges PY, PM, PC, and PK and toner cartridges 430Y, 430M, 430C, and 430K (described later) may be referred to as the main body of the image forming apparatus 100 or the apparatus main body 72. In the following description, the toner cartridges 430Y, 430M, 430C, and 430K may be simply referred to as cartridges 430Y, 430M, 430C, and 430K. The toner cartridge 430K is an example of a first toner container capable of replenishing black toner together with air to the developing container 43K, and the toner cartridge 430C is an example of a second toner container capable of replenishing cyan toner together with air to the developing container 43C. The process cartridges PY, PM, PC, and PK may be detachably supported by the apparatus main body 72 or may be non-detachably fixed to the apparatus main body 72.

[0012] In this embodiment, the reference numerals of the components corresponding to the yellow, magenta, cyan, and black toners are given the suffixes P, Y, M, C, and K. The configurations and operations of the components given these suffixes are essentially the same except for the toner colors. Therefore, in the following, unless a particular distinction is required, the suffixes Y to K may be omitted and the components may be generally described.

[0013] Furthermore, in the following explanation, unless otherwise specified, it is assumed that the process cartridges PY, PM, PC, PK and toner cartridges 430Y, 430M, 430C, 430K are in their normal positions, i.e., the positions when they are installed in the device main body 72, and directions (X, Y, Z) are defined as follows:

[0014] 2(a), the front-to-rear direction is indicated by the X axis, and the direction from the back to the front of the image forming apparatus 100 is referred to as the X direction. The X direction may also be referred to as the second direction, the front direction, the near direction, or the toner cartridge installation / removal direction. The downstream side of the image forming apparatus 100 in the X direction may also be referred to as the front side, and the upstream side may also be referred to as the rear side.

[0015] The left-right direction is indicated by the Y axis, and the direction from left to right of image forming apparatus 100 is referred to as the Y direction. The Y direction may also be referred to as the direction of rotation axis AL1, the first direction, or the right direction. The downstream side of image forming apparatus 100 in the Y direction may also be referred to as the right side, and the upstream side may also be referred to as the left side.

[0016] The vertical direction is indicated by the Z axis, and the direction from the bottom to the top of image forming apparatus 100 is referred to as the Z direction. The Z direction may also be referred to as the third direction, upward direction, height direction, or vertical direction. The downstream side of image forming apparatus 100 in the Z direction may also be referred to as the upper side, top side, or top surface side, and the upstream side may also be referred to as the lower side, bottom side, or bottom surface side.

[0017] The X-axis, Y-axis, and Z-axis are perpendicular to each other. For example, the X-axis is perpendicular to both the Y-axis and the Z-axis. A plane perpendicular to the X-axis is sometimes called the YZ-plane, a plane perpendicular to the Y-axis is sometimes called the ZX-plane, and a plane perpendicular to the Z-axis is sometimes called the XY-plane. For example, the XY-plane is a horizontal plane. The X-direction and Y-direction are directions along the horizontal XY-plane, i.e., the horizontal direction.

[0018] The process cartridge PY has a drum unit 8Y and a developing unit 9Y. The drum unit 8Y has a photosensitive drum 44Y and a charging roller 45Y. The photosensitive drum 44Y is configured by coating the outer periphery of an aluminum cylinder with an organic photoconductive layer and is rotated by a drive motor (not shown). Note that a photosensitive belt may be used instead of the photosensitive drum 44Y. The developing unit 9Y has a developer container 43Y that contains yellow toner and a developing roller 46Y that develops the electrostatic latent image on the photosensitive drum 44Y.

[0019] Similarly, the process cartridge PM has a drum unit 8M and a developing unit 9M. The drum unit 8M has a photosensitive drum 44M and a charging roller 45M. The photosensitive drum 44M is configured by coating the outer periphery of an aluminum cylinder with an organic photoconductive layer and is rotated by a drive motor (not shown). Note that a photosensitive belt may be used instead of the photosensitive drum 44M. The developing unit 9M has a developer container 43M that contains magenta toner and a developing roller 46M that develops the electrostatic latent image on the photosensitive drum 44M.

[0020] The process cartridge PC also includes a drum unit 8C and a developing unit 9C. The drum unit 8C includes a photosensitive drum 44C as a second photosensitive member and a charging roller 45C. The photosensitive drum 44C is configured by coating the outer periphery of an aluminum cylinder with an organic photoconductive layer and is rotated by a drive motor (not shown). A photosensitive belt may be used instead of the photosensitive drum 44C. The developing unit 9C as a second developing unit includes a developing container 43C that contains cyan toner and a developing roller 46C that develops the electrostatic latent image on the photosensitive drum 44C. That is, the developing container 43C as a second developing container is configured to contain cyan toner as a second toner, and the developing roller 46C as a second developing roller is configured to carry cyan toner.

[0021] The process cartridge PK also includes a drum unit 8K and a developing unit 9K. The drum unit 8K includes a photosensitive drum 44K as a first photosensitive member and a charging roller 45K. The photosensitive drum 44K is configured by coating the outer periphery of an aluminum cylinder with an organic photoconductive layer and is rotated by a drive motor (not shown). Note that a photosensitive belt may be used instead of the photosensitive drum 44K. The developing unit 9K as a first developing unit includes a developing container 43K that contains black toner and a developing roller 46K that develops the electrostatic latent image on the photosensitive drum 44K. That is, the developing container 43K as a first developing container is configured to contain black toner as a first toner, and the developing roller 46K as a first developing roller is configured to carry black toner.

[0022] These four process cartridges PY, PM, PC, and PK are arranged side by side in the X direction. The image forming section 40 also includes an intermediate transfer belt unit 11 arranged below the process cartridges PY, PM, PC, and PK. The intermediate transfer belt unit 11 includes an intermediate transfer belt 12 wound around a drive roller 14, a tension roller 13, and an assist roller 15, and a secondary transfer roller 17. The intermediate transfer belt 12 is rotated clockwise in FIG. 1 by the drive roller 14. Primary transfer rollers 16Y, 16M, 16C, and 16K are provided inside the intermediate transfer belt 12.

[0023] Primary transfer rollers 16Y, 16M, 16C, and 16K are in contact with photosensitive drums 44Y, 44M, 44C, and 44K, respectively, and form primary transfer sections 30Y, 30M, 30C, and 30K. Secondary transfer roller 17 is disposed opposite drive roller 14 across intermediate transfer belt 12. Secondary transfer roller 17 and intermediate transfer belt 12 are in contact with each other, and form secondary transfer section 31.

[0024] The fixing unit 21 has a fixing film 21a heated by a heater, and a pressure roller 21b that presses against the fixing film 21a. The feeding unit 18 is provided in the lower part of the image forming apparatus 100. The feeding unit 18 has a feeding cassette 19 that can be pulled out and attached to the apparatus main body 72, and a feeding roller 20 that feeds the sheets S stored in the feeding cassette 19. The feeding unit 18 also has a manual feeding port 330 through which sheets are manually inserted. The sheets include paper such as paper sheets and envelopes, plastic films such as overhead projector sheets (OHP), cloth, etc.

[0025] [Image formation operation] Next, an image forming operation of the image forming apparatus 100 configured as described above will be described. When an image signal is input to the laser scanner LB from a personal computer (not shown) or the like, the laser scanner LB emits laser beams LY, LM, LC, and LK corresponding to the image signal. The laser beams LY, LM, LC, and LK for exposing each photosensitive drum are irradiated onto the photosensitive drums 44Y, 44M, 44C, and 44K through exposure windows 10Y, 10M, 10C, and 10K of the laser scanner LB.

[0026] At this time, the surface of the photosensitive drum 44Y is uniformly charged to a predetermined polarity and potential by the charging roller 45Y, and an electrostatic latent image is formed on the surface by irradiating it with laser light LY from the laser scanner LB. The electrostatic latent image formed on the photosensitive drum 44Y is developed by the developing roller 46Y, and a yellow (Y) toner image is formed on the photosensitive drum 44Y.

[0027] Similarly, magenta (M), cyan (C), and black (K) toner images are formed on the photosensitive drums 44M, 44C, and 44K. The toner images of each color formed on each photosensitive drum are transferred onto the intermediate transfer belt 12 by primary transfer rollers 16Y, 16M, 16C, and 16K, and are transported to the secondary transfer roller 17 by the intermediate transfer belt 12 rotated by the drive roller 14.

[0028] The image forming process for each color is performed at a timing to overlap an upstream toner image that has been primarily transferred onto the intermediate transfer belt 12. After the toner images for each color are transferred onto the intermediate transfer belt 12, the toner remaining on the surface of each photosensitive drum is removed by a cleaning device (not shown).

[0029] In parallel with this image formation process, a sheet S stored in a feeding cassette 19 of a feeding unit 18 or a sheet supplied from a manual feeding port 330 is conveyed toward a secondary transfer section 31. In the secondary transfer section 31, a full-color toner image on the intermediate transfer belt 12 is transferred onto the sheet S by a secondary transfer bias applied to a secondary transfer roller 17. A fixing film 21a and a pressure roller 21b of a fixing unit 21 apply predetermined heat and pressure to the sheet S onto which the toner image has been transferred, thereby melting and fixing (fixing) the toner. After passing through the fixing unit 21, the sheet S is discharged in the X direction by a pair of discharge rollers 22 and is stacked on a discharge tray 23 provided at the top of the device main body 72.

[0030] [Outline of toner cartridge configuration] Next, the schematic configuration of the toner cartridges 430Y, 430M, 430C, and 430K will be described with reference to Figures 2(a) to 2(c). Figure 2(a) is a perspective view showing the image forming apparatus 100, Figure 2(b) is a perspective view showing the image forming apparatus 100 with the front door 72b open, and Figure 2(c) is a perspective view showing the image forming apparatus 100 with the toner cartridge 430Y removed.

[0031] As shown in Fig. 2(a), the image forming apparatus 100 has a front door 72b that is supported on the housing of the apparatus main body 72 so as to be able to open and close. As shown in Figs. 2(a) and 2(b), the front door 72b covers an opening 72a provided at the front of the apparatus main body 72, i.e., at the downstream end in the X direction, when positioned at the closed position. Furthermore, as shown in Fig. 2(b), the front door 72b opens the opening 72a of the apparatus main body 72 when positioned at the open position. The front door 72b can maintain its posture in the open position.

[0032] 2(b), when the front door 72b is opened from the closed position to the open position, the toner cartridges 430Y, 430M, 430C, and 430K are exposed to the outside of the image forming apparatus 100 through the opening 72a. This allows the user to access the toner cartridges 430Y, 430M, 430C, and 430K. The toner cartridges 430Y, 430M, 430C, and 430K can replenish toner to the developing containers 43Y, 43M, 43C, and 43K of the process cartridges PY, PM, PC, and PK.

[0033] The toner cartridges 430Y, 430M, 430C, and 430K are disposed downstream in the X direction and downstream in the Z direction of the device main body 72, i.e., on the front side and upper side of the device main body 72. In other words, the toner cartridges 430Y, 430M, 430C, and 430K are disposed downstream of the device main body 72 in the sheet discharge direction of the discharge roller pair 22. The toner cartridges 430Y, 430M, 430C, and 430K are also disposed side by side in the Y direction, which is the arrangement direction, i.e., aligned. In other words, the X direction, which is the alignment direction of the process cartridges PY, PM, PC, and PK, and the Y direction, which is the alignment direction of the toner cartridges 430Y, 430M, 430C, and 430K, are perpendicular to each other.

[0034] As shown in FIG. 2(c), the toner cartridges 430Y, 430M, 430C, and 430K are supported by a cartridge holder 51 provided in the apparatus main body 72 so as to be detachable in the X direction. That is, the X direction (as well as the -X direction) as a second direction intersecting the Y direction is the attachment / detachment direction of the toner cartridges 430Y, 430M, 430C, and 430K. Therefore, the toner cartridges 430Y, 430M, 430C, and 430K can be replaced without removing the process cartridges PY, PM, PC, and PK from the apparatus main body 72. The toner cartridges 430Y, 430M, 430C, and 430K are located on the front side of the apparatus main body 72 and are exposed by opening the front door 72b, allowing for easy replacement.

[0035] The cartridge holder 51 is disposed on the front side of the apparatus main body 72 and downstream of the process cartridges PY, PM, PC, and PK in the X direction. Therefore, even when the toner cartridges 430Y, 430M, 430C, and 430K are removed from the cartridge holder 51, the process cartridges PY, PM, PC, and PK are covered by the cartridge holder 51 and are not exposed to the outside of the image forming apparatus 100 through the opening 72a. The toner cartridges 430Y, 430M, 430C, and 430K are housed within the apparatus main body 72 with the front door 72b in the closed position.

[0036] 2A, indicators 208Y, 208M, 208C, and 208K are provided on the front surface 72c of the apparatus main body 72. These indicators 208Y, 208M, 208C, and 208K are intended to clearly indicate to the user the color of the toner contained in the toner cartridges 430Y, 430M, 430C, and 430K. The indicators 208Y, 208M, 208C, and 208K are configured with LEDs, stickers, or the like. For example, the indicator 208Y is configured with an LED that lights up or flashes yellow, or a yellow sticker. The indicators 208Y, 208M, 208C, and 208K may also have the function of displaying the remaining amount of toner contained in the corresponding process cartridges PY, PM, PC, and PK.

[0037] As shown in FIG. 2(b), an inclined portion 51a is formed on the lower portion of the cartridge holder 51. The inclined portion 51a is a slope that faces diagonally upward. In other words, the inclined portion 51a is a slope that extends downstream in the Z direction as it moves upstream in the X direction. Labels 210Y, 210M, 210C, and 210K corresponding to the colors of the toner contained in the toner cartridges 430Y, 430M, 430C, and 430K are attached to the inclined portion 51a. For example, the labels 210Y, 210M, 210C, and 210K are colored yellow, magenta, cyan, and black, respectively, or have the letters yellow, magenta, cyan, and black written on them. When replacing the toner cartridges 430Y, 430M, 430C, and 430K, the user can visually check the labels 210Y, 210M, 210C, and 210K attached to the inclined portion 51a, which allows the user to install each toner cartridge in the appropriate position.

[0038] [Image formation unit] Next, using Figures 3(a) to 5(b), an image forming unit 500 including a toner transport mechanism for transporting toner from the toner cartridges 430Y, 430M, 430C, and 430K to the process cartridges PY, PM, PC, and PK will be described. Figure 3(a) is a perspective view showing the image forming unit 500, and Figure 3(b) is a perspective view showing the image forming unit 500 with the toner cartridges 430Y, 430M, 430C, and 430K removed.

[0039] Fig. 4(a) is a plan view showing the laser scanner LB and the image forming unit 500, and Fig. 4(b) is a plan view showing the image forming unit 500. Fig. 5(a) is a cross-sectional view showing the 5A-5A cross section of Fig. 4(a), and Fig. 5(b) is a cross-sectional view showing the 5B-5B cross section of Fig. 4(a).

[0040] 3(a) and 3(b), the image forming unit 500 has process cartridges PY, PM, PC, and PK, toner cartridges 430Y, 430M, 430C, and 430K, a cartridge holder 51, and a pump unit 1. As shown in FIGS. 1 and 3(a), the pump unit 1 is disposed behind the cartridge holder 51 and above the process cartridge PK.

[0041] 3(b), the air delivered from the pump unit 1 is discharged from discharge holes 514a, 514b, 514c, and 514d provided in the cartridge holder 51. The discharge holes 514a, 514b, 514c, and 514d are open upward, i.e., in the Z direction.

[0042] Further, receiving openings 51aY, 51aM, 51aC, and 51aK are provided in the cartridge holder 51. The receiving openings 51aY, 51aM, 51aC, and 51aK are through holes provided in the back surface of the cartridge holder 51. The opening direction of the receiving openings 51aY, 51aM, 51aC, and 51aK is the X direction, which intersects with the Z direction, which is the opening direction of the discharge holes 514a, 514b, 514c, and 514d.

[0043] When the toner cartridges 430Y, 430M, 430C, and 430K are attached to the cartridge holder 51, air is discharged from the discharge holes 514a, 514b, 514c, and 514d and supplied to the interiors of the toner cartridges 430Y, 430M, 430C, and 430K. The toner discharged together with the air from the toner cartridges 430Y, 430M, 430C, and 430K is received by the supply pipes 62Y, 62M, 62C, and 62K via the receiving ports 51aY, 51aM, 51aC, and 51aK of the cartridge holder 51.

[0044] As shown in Figure 4(b), the supply pipes 62Y, 62M, 62C, and 62K have upstream ends 62Yu, 62Mu, 62Cu, and 62Ku connected to the receiving ports 51aY, 51aM, 51aC, and 51aK, respectively, and downstream ends 62Yd, 62Md, 62Cd, and 62Kd connected to the developing containers 43Y, 43M, 43C, and 43K, respectively.

[0045] The toner discharged together with the air from the toner cartridges 430Y, 430M, 430C, and 430K passes through the supply pipes 62Y, 62M, 62C, and 62K and is supplied to the developing containers 43Y, 43M, 43C, and 43K.

[0046] The supply pipes 62Y and 62Md are arranged at the upstream ends of the developer containers 43Y and 43M, respectively, in the Y direction. The supply pipes 62C and 62K are arranged at the downstream ends of the developer containers 43C and 43K, respectively, in the Y direction. By arranging the supply pipes 62Y, 62M, 62C, and 62K on the left and right sides of the developer containers 43Y, 43M, 43C, and 43K in this manner, the lengths of the supply pipes 62Y, 62M, 62C, and 62K can be shortened. This reduces pressure loss in the supply pipes 62Y, 62M, 62C, and 62K, and allows the image forming unit 500 to be made smaller.

[0047] Next, the arrangement of the toner cartridge 430Y will be described. As shown in FIG. 5B, the toner cartridge 430Y and the process cartridges PY, PM, PC, and PK are arranged so as to overlap with an imaginary line VL1 extending in the X direction. That is, as shown in FIGS. 1 and 6B, the toner cartridges 430Y, 430M, 430C, and 430K are arranged side by side with the process cartridges PY, PM, PC, and PK in the X direction. In other words, when viewed in the X direction, at least a portion of each toner cartridge 430Y, 430M, 430C, and 430K is arranged so as to overlap with the process cartridges PY, PM, PC, and PK in the Z direction. This allows the image forming unit 500 to be made smaller in the Z direction, i.e., the up-down direction, and thus the image forming apparatus 100 can be made smaller.

[0048] In the present embodiment, the toner cartridges 430Y, 430M, 430C, and 430K are arranged as described above, but the present invention is not limited to this. That is, the toner cartridges 430Y, 430M, 430C, and 430K may be arranged higher than the process cartridges PY, PM, PC, and PK in the Z direction.

[0049] Furthermore, it is preferable that the image forming unit 500 be configured to allow easy access to the process cartridges PY, PM, PC, PK and the replenishment pipes 62Y, 62M, 62C, 62K for maintenance or replacement of the process cartridges PY, PM, PC, PK, the replenishment pipes 62Y, 62M, 62C, 62K, etc. For this reason, in the present embodiment, the image forming unit 500 has a tray 55 that supports the process cartridges PY, PM, PC, PK, and the cartridge holder 51. The tray 55 is configured to be removable in the X direction from the apparatus main body 72. By removing the tray 55 in the X direction with the front door 72b open, the user can easily access the process cartridges PY, PM, PC, PK, the toner cartridges 430Y, 430M, 430C, 430K supported by the cartridge holder 51, and the pump unit 1.

[0050] [Pump unit] Next, the pump unit 1 will be described with reference to FIGS. 6 and 7. FIG. 6 is a perspective view showing the pump unit 1 according to this embodiment. FIG. 7 is an exploded perspective view showing the pump unit 1. The pump unit 1 shown in FIGS. 6 and 7 is rotated 180 degrees about the X-axis from the pump unit 1 shown in FIGS. 1 to 5(b). That is, the short side direction of the pump unit 1 is indicated by the X-axis, and the direction from the back to the front of the pump unit 1 is referred to as the X-direction. The direction of the rotation axes of the first and second dual-shaft motors 4L and 4R of the pump unit 1 is indicated by the Y-axis, and the direction from the second dual-shaft motor 4R to the first dual-shaft motor 4L is referred to as the Y-direction. The Y-direction may also be referred to as the axial direction or longitudinal direction. The up-down direction of the pump unit 1 is indicated by the Z-axis, and the Z-direction may also be referred to as the height direction or vertical direction.

[0051] 6 and 7, the pump unit 1 includes a first double-shaft motor 4L, a second double-shaft motor 4R, a first drive transmission unit 5L1, a second drive transmission unit 5L2, a third drive transmission unit 5R1, and a fourth drive transmission unit 5R2. The pump unit 1 also includes a first pump 3L1, a second pump 3L2, a third pump 3R1, a fourth pump 3R2, a first holding member 7L, a second holding member 7R, a first pipe 6L1, a second pipe 6L2, a third pipe 6R1, and a fourth pipe 6R2.

[0052] The first pump 3L1 conveys (sends) air to the first pipe 6L1 by transmitting the drive of the first double-axial motor 4L via the first drive transmission unit 5L1. The first pipe 6L1 is connected to a flow path (not shown) provided in the cartridge holder 51. The air sent to the first pipe 6L1 is then conveyed to the discharge hole 514d via the flow path. The discharge hole 514d is connected to an intake port of the toner cartridge 430K (described later), and air is supplied to the toner cartridge 430K from the discharge hole 514d.

[0053] The second pump 3L2 transfers air to the second pipe 6L2 by transmitting the drive of the first double-axial motor 4L via the second drive transmission unit 5L2. The second pipe 6L2 is connected to a flow path (not shown) provided in the cartridge holder 51. The air sent to the second pipe 6L2 is then transported through the flow path to the discharge hole 514c. The discharge hole 514c is connected to an intake port of the toner cartridge 430C (described later), and air is supplied to the toner cartridge 430C from the discharge hole 514d.

[0054] The third pump 3R1 transfers air to the third pipe 6R1 by transmitting the drive of the second double-axial motor 4R via the third drive transmission part 5R1. The third pipe 6R1 is connected to a flow path (not shown) provided in the cartridge holder 51. The air sent to the third pipe 6R1 is then transferred to the discharge hole 514b via the flow path. The discharge hole 514b is connected to an intake port of the toner cartridge 430M (described later), and air is supplied to the toner cartridge 430M from the discharge hole 514b.

[0055] The fourth pump 3R2 conveys air to a fourth pipe 6R2 by receiving drive power from the second double-axial motor 4R via a fourth drive transmission unit 5R2. The fourth pipe 6R2 is connected to a flow path (not shown) provided in the cartridge holder 51. The air sent to the fourth pipe 6R2 is then conveyed to a discharge hole 514a via the flow path. The discharge hole 514a is connected to an intake port 430Yb1 of the toner cartridge 430Y (described later), and air is supplied to the toner cartridge 430Y from the discharge hole 514b.

[0056] The above-mentioned flow paths provided in the cartridge holder 51 are formed independently within the cartridge holder 51 and do not communicate with each other.

[0057] The pump unit 1 has a mounting member 37, and the first double-shaft motor 4L is held by a first holding member 7L attached to the mounting member 37. The second double-shaft motor 4R is held by a second holding member 7R attached to the mounting member 37.

[0058] The first double-shaft motor 4L includes a first rotating shaft 4Ls as a rotating shaft extending in the Y direction and a first housing 4Lc that rotatably supports the first rotating shaft 4Ls. The first rotating shaft 4Ls penetrates the first housing 4Lc and is configured to be rotatable about a rotation axis AL1 in a first rotation direction R1 and a second rotation direction R2 opposite to the first rotation direction R1. The first rotating shaft 4Ls also includes a first protrusion 4La that protrudes from one side of the first housing 4Lc in the Y direction and a second protrusion 4Lb that protrudes from the other side of the first housing 4Lc. The first protrusion 4La, which serves as a first end, is located on one side of the first rotating shaft 4Ls in the Y direction, and the first protrusion 4Lb, which serves as a second end, is located on the other side of the first rotating shaft 4Ls in the Y direction.

[0059] The second double-shaft motor 4R has a second rotating shaft 4Rs extending in the Y direction and a second housing 4Rc that rotatably supports the second rotating shaft 4Rs. The second rotating shaft 4Rs penetrates the second housing 4Rc and is configured to be rotatable about a rotation axis AL1 in a third rotation direction R3 and a fourth rotation direction R4 opposite to the third rotation direction R3. The second rotating shaft 4Rs also has a third protrusion 4Ra that protrudes from one side of the second housing 4Rc in the Y direction and a fourth protrusion 4Rb that protrudes from the other side of the second housing 4Rc. The third protrusion 4Ra, which serves as a third end, is located on one side of the second rotating shaft 4Rs in the Y direction, and the fourth protrusion 4Rb, which serves as a fourth end, is located on the other side of the second rotating shaft 4Rs in the Y direction.

[0060] A first drive transmission unit 5L1 and a second drive transmission unit 5L2 are attached to the first protrusion 4La and the second protrusion 4Lb of the first dual-shaft motor 4L, respectively. As shown in FIG. 7, the first drive transmission unit 5L1 includes a first clutch unit 5dL1 and a first eccentric shaft 5eL1 provided on the output member 5c of the first clutch unit 5dL1. The first clutch unit 5dL1 includes an input member 5a to which drive is input from the first protrusion 4La, an output member 5c, and a clutch member 5b disposed between the input member 5a and the output member 5c. The clutch member 5b rotates in response to the input member 5a, which rotates together with the first protrusion 4La. The clutch member 5b transmits or cuts off drive to the output member 5c.

[0061] The clutch member 5b has a sawtooth surface and transmits driving force to the output member 5c only when the first rotating shaft 4Ls of the first double-shaft motor 4L rotates in the first rotation direction R1. That is, the first clutch portion 5dL1 is in a transmitting state when the first rotating shaft 4Ls rotates in the first rotation direction R1, and is in a non-transmitting state in which driving force is not transmitted when the first rotating shaft 4Ls rotates in the second rotation direction R2.

[0062] The first eccentric shaft 5eL1 provided on the output member 5c is eccentric with respect to the first rotation shaft 4Ls and rotates integrally with the output member 5c, which rotates around the first rotation shaft 4Ls. The first eccentric shaft 5eL1 is connected to the first pump 3L1, and the first pump 3L1 is activated when the first eccentric shaft 5eL1 rotates around the first rotation shaft 4Ls in the first rotation direction R1. When the first pump 3L1 is activated, air is discharged from the first discharge portion 35L1 of the first pump 3L1. As shown in FIG. 6, a first pipe 6L1 is connected to the first discharge portion 35L1, and the air discharged from the first discharge portion 35L1 is sent through the first pipe 6L1 toward the toner cartridge 430K.

[0063] 6 and 7, the second drive transmission unit 5L2 has a second clutch unit and a second eccentric shaft 5eL2 provided on the output member of the second clutch unit. The second clutch unit has a configuration similar to that of the first clutch unit 5dL1, and is disposed symmetrically with the first clutch unit 5dL1 in the Y direction with respect to the first housing 4Lc.

[0064] The second eccentric shaft 5eL2 provided on the output member of the second clutch unit is eccentric with respect to the first rotary shaft 4Ls and rotates integrally with the output member, which rotates around the first rotary shaft 4Ls. The second eccentric shaft 5eL2 is connected to the second pump 3L2, and the second pump 3L2 is activated when the second eccentric shaft 5eL2 rotates around the first rotary shaft 4Ls in the second rotation direction R2. When the second pump 3L2 is activated, air is discharged from the second discharge portion 35L2 of the second pump 3L2. As shown in FIG. 6, a second pipe 6L2 is connected to the second discharge portion 35L2, and the air discharged from the second discharge portion 35L2 is sent through the second pipe 6L2 toward the toner cartridge 430C.

[0065] A third drive transmission unit 5R1 and a fourth drive transmission unit 5R2 are attached to the third protrusion 4Ra and the fourth protrusion 4Rb of the second dual-shaft motor 4R, respectively. As shown in Figures 6 and 7, the third drive transmission unit 5R1 has a third clutch unit and a third eccentric shaft 5eR1 provided on the output member of the third clutch unit. The third clutch unit has a configuration similar to that of the first clutch unit 5dL1.

[0066] The third eccentric shaft 5eR1, which is provided on the output member of the third clutch unit, is eccentric to the second rotary shaft 4Rs and rotates integrally with the output member, which rotates around the second rotary shaft 4Rs. The third eccentric shaft 5eR1 is connected to the third pump 3R1, and the third pump 3R1 is activated when the third eccentric shaft 5eR1 rotates around the second rotary shaft 4Rs in the third rotation direction R3. When the third pump 3R1 is activated, air is discharged from the third discharge portion 35R1 of the third pump 3R1. As shown in FIG. 6, a third pipe 6R1 is connected to the third discharge portion 35R1, and the air discharged from the third discharge portion 35R1 is sent through the third pipe 6R1 toward the toner cartridge 430M.

[0067] 6 and 7, the fourth drive transmission unit 5R2 has a fourth clutch unit and a fourth eccentric shaft 5eR2 provided on the output member of the fourth clutch unit. The fourth clutch unit has a configuration similar to that of the first clutch unit 5dL1, and is disposed symmetrically with the third clutch unit in the Y direction with respect to the second housing 4Rc.

[0068] The fourth eccentric shaft 5eR2, which is provided on the output member of the fourth clutch unit, is eccentric to the second rotary shaft 4Rs and rotates integrally with the output member, which rotates around the second rotary shaft 4Rs. The fourth eccentric shaft 5eR2 is connected to the fourth pump 3R2, and the fourth pump 3R2 is activated when the fourth eccentric shaft 5eR2 rotates around the second rotary shaft 4Rs in the fourth rotation direction R4. When the fourth pump 3R2 is activated, air is discharged from the fourth discharge portion 35R2 of the fourth pump 3R2. As shown in FIG. 6, a fourth pipe 6R2 is connected to the fourth discharge portion 35R2, and the air discharged from the fourth discharge portion 35R2 is sent through the fourth pipe 6R2 toward the toner cartridge 430Y.

[0069] As described above, the clutch portions have the same configuration, but can transition to a transmission state or a non-transmission state depending on the rotation direction of the first rotating shaft 4Ls and the rotation direction of the second rotating shaft 4Rs.

[0070] That is, when the first rotating shaft 4Ls of the first double-shaft motor 4L rotates in the first rotation direction R1, the first clutch portion 5dL1 is in the engaged state and the second clutch portion is in the disengaged state. Therefore, the first pump 3L1 is operated and the second pump 3L2 is not operated. On the other hand, when the first rotating shaft 4Ls of the first double-shaft motor 4L rotates in the second rotation direction R2, the first clutch portion 5dL1 is in the disengaged state and the second clutch portion is in the engaged state. Therefore, the first pump 3L1 is not operated and the second pump 3L2 is operated.

[0071] Furthermore, when the second rotating shaft 4Ls of the second double-shaft motor 4L rotates in the third rotational direction R3, the third clutch portion is in the transmission state and the fourth clutch portion is in the disengagement state. Therefore, the third pump 3R1 is operated and the fourth pump 3R2 is not operated. Also, as described above, when the second rotating shaft 4Ls of the second double-shaft motor 4L rotates in the fourth rotational direction R4, the third clutch portion is in the disengagement state and the fourth clutch portion is in the transmission state. Therefore, the third pump 3R1 is not operated and the fourth pump 3R2 is operated.

[0072] The transmission states of the first clutch portion 5dL1, the second clutch portion, the third clutch portion, and the fourth clutch portion are also referred to as the first transmission state, the second transmission state, the third transmission state, and the fourth transmission state, respectively.Furthermore, the states of the first drive transmission portion 5L1, the second drive transmission portion 5L2, the third drive transmission portion 5R1, and the fourth drive transmission portion 5R2 at this time can also be referred to as the first transmission state, the second transmission state, the third transmission state, and the fourth transmission state, respectively.

[0073] The non-transmission states of the first clutch portion 5dL1, the second clutch portion, the third clutch portion, and the fourth clutch portion are also referred to as the first non-transmission state, the second non-transmission state, the third non-transmission state, and the fourth non-transmission state, respectively.Furthermore, the states of the first power transmission portion 5L1, the second power transmission portion 5L2, the third power transmission portion 5R1, and the fourth power transmission portion 5R2 at this time can also be referred to as the first non-transmission state, the second non-transmission state, the third non-transmission state, and the fourth non-transmission state, respectively.

[0074] The above-described configurations of the clutch units are merely examples and are not limiting. That is, the clutch unit may be configured in any way as long as it changes the interruption or transmission of drive to the output shaft depending on the rotation direction of the rotating shaft.

[0075] [Pump detailed configuration] Next, the detailed configuration of each pump will be described using Figure 3. As each pump has a similar configuration as described above, the following description will use the first pump 3L1 as an example. As shown in Figure 3, the first pump 3L1 has a base member 36L1 fixed to a mounting member 37 and a membrane member 31L1 sandwiched between the mounting member 37 and the base member 36L1. The base member 36L1 has an intake section 34 through which air is drawn, an exhaust section 35L1 through which air is exhausted, and a hole (not shown).

[0076] The membrane member 31L1 has a flat portion 31b and a pillar portion 31bL1 extending in the Z direction from the flat portion 31b. When the base member 36L1 and the membrane member 31L1 are attached to the attachment member 37, the pillar portion 31bL1 of the membrane member 31L1 passes through a hole in the base member 36L1. An intake valve 31c and a discharge valve 31d are provided on the flat portion 31b. The pillar portion 31bL1 is provided with a shaft hole 31aL1 into which the first eccentric shaft 5eL1 is inserted via a bearing 32. In other words, the first eccentric shaft 5eL1 is rotatably supported in the shaft hole 31aL1 via the bearing 32.

[0077] The mounting member 37 has a recess 37a at a position corresponding to the flat surface 31b of the membrane member 31L1. When the membrane member 31L1 and the base member 36L1 are attached to the mounting member 37, the recess 37a of the mounting member 37 and the flat surface 31b of the membrane member 31L1 form a volume change portion 33L1. The volume change portion 33L1 is a space surrounded by the recess 37a and the flat surface 31b, and the first pump 3L1 is a diaphragm pump that can change the volume of the volume change portion 33L1, which is the internal space. The volume of the volume change portion 33L1 repeatedly increases and decreases as the membrane member 31L1 moves in accordance with the rotation of the first eccentric shaft 5eL1. As a result, the first pump 3L1 functions as a diaphragm pump that draws air through the suction portion 34 and discharges air through the discharge portion 35L1.

[0078] The second pump 3L2, the third pump 3R1, and the fourth pump 3R2 have the same configuration as the first pump 3L1, and can pump air by rotating their respective eccentric shafts. In this way, the pump unit 1 can operate any of the pumps (3L1, 3L2, 3R1, 3R2) by switching the rotation direction of the rotating shafts (4Ls, 4Rs) of the first double-shaft motor 4L and the second double-shaft motor 4R.

[0079] [Toner cartridge configuration] Next, the schematic configuration of the toner cartridge 430Y will be described with reference to FIGS. 8(a) to 10(b). FIG. 8(a) is a front view of the toner cartridge 430Y, and FIG. 8(b) is a plan view of the toner cartridge 430Y. FIG. 8(c) is a bottom view of the toner cartridge 430Y, FIG. 8(d) is a side view of the toner cartridge 430Y, and FIG. 8(e) is a rear view of the toner cartridge 430Y. FIG. 9(a) is a cross-sectional view showing the 9A-9A cross section of FIG. 8(e), and FIG. 9(b) is a perspective view of the toner cartridge 430Y cut along the XZ plane. FIG. 9(c) is an exploded view of the toner cartridge 430Y cut along the XZ plane. FIG. 10(a) is a cross-sectional view showing the 10A-10A cross section of FIG. 8(b), and FIG. 10(b) is a perspective view of the toner cartridge 430Y cut along the YZ plane.

[0080] As shown in FIG. 3A, the toner cartridge 430K has a width La in the Y direction, which is wider than the width Lb1 of each of the toner cartridges 430Y, 430M, and 430C. Therefore, the toner capacity of the toner cartridge 430K is larger than the capacity of each of the toner cartridges 430Y, 430M, and 430C. Generally, black toner is consumed in greater quantities than the other colors of toner, but as described above, the toner cartridge 430K can accommodate more toner than the other toner cartridges 430Y, 430M, and 430C. This allows the number of replacement times for the toner cartridges 430Y, 430M, 430C, and 430K to be equalized, improving usability.

[0081] Since the toner cartridges 430Y, 430M, 430C, and 430K have the same configuration except for their width in the Y direction, only the toner cartridge 430Y will be described below, and descriptions of the toner cartridges 430M, 430C, and 430K will be omitted. Note that the following description of the toner cartridge 430Y will be given with the toner cartridge 430Y attached to the cartridge holder 51.

[0082] As shown in Figures 8(a) to 10(b), the toner cartridge 430Y has a first frame 430Ya, a second frame 430Yb, a filter 83Y, and a discharge pipe 85Y. In this embodiment, the first frame 430Ya and the second frame 430Yb are made of a resin material, but they may also be made of paper, rubber, or the like. The filter 83Y is formed in a sheet shape and is fixed in a state where it is sandwiched between the first frame 430Ya and the second frame 430Yb.

[0083] The internal space SPY of the toner cartridge 430Y is partitioned by a filter 83Y into a toner storage chamber 430Yc and an air chamber 430Yd. That is, the toner storage chamber 430Yc is formed by the first frame 430Ya and the filter 83Y, and the air chamber 430Yd is formed by the second frame 430Yb and the filter 83Y. The air chamber 430Yd is located below the filter 83Y, and the toner storage chamber 430Yc is located above the filter 83Y.

[0084] The toner storage chamber 430Yc is configured to store toner T (see FIG. 9(a)), and the toner T is supported in the toner storage chamber 430Yc in the direction of gravity (-Z direction) by the filter 83Y. No toner T is stored in the air chamber 430Yd. The filter 83Y is made of a porous member made of, for example, resin fibers. The pores of the filter 83Y have a size and density that allows air to pass through but restricts the passage of toner T. In other words, the filter 83Y is configured to allow air to pass through but prevent the passage of toner T.

[0085] A flange portion 430Ya2 extending along the XY plane is formed at the lower end of the first frame 430Ya, and a flange portion 430Yb3 extending along the XY plane is formed at the upper end of the second frame 430Yb. These flange portions 430Ya2, 430Yb3 are ultrasonically welded to each other, thereby joining the first frame 430Ya and the second frame 430Yb, and the outer edge portion 83Ya of the filter 83Y is sandwiched between the first frame 430Ya and the second frame 430Yb. Note that the flange portions 430Ya2, 430Yb3 may be fixed to each other not only by ultrasonic welding, but also by heat welding, adhesives such as double-sided tape or hot melt, screws, etc.

[0086] The filter 83Y is inclined from the outer edge 83Ya toward the lowest part 83Yb, which is located below the outer edge 83Ya. That is, the filter 83Y has an inclined portion that slopes downward in the X direction, Y direction, or horizontal direction toward (closer to) the lowest part 83Yb. The lowest part 83Yb is a portion that protrudes from the outer edge 83Ya in the direction from the toner storage chamber 430Yc toward the air chamber 430Yd. As shown in FIGS. 9(a) and 10(b), the lowest part 83Yb is located in the center of the filter 83Y in the X direction and the Y direction.

[0087] 8(e), a discharge port 430Ya1 is provided on the rear surface 4300Ya of the first frame 430Ya, through which the toner in the toner storage chamber 430Yc is discharged to the outside of the toner cartridge 430Y. The discharge port 430Ya1 is formed of a through-hole that penetrates the first frame 430Ya in the X direction.

[0088] 8(a), (c), and (e), a convex portion 4301 is provided on the bottom surface 4300Yb of the second frame 430Yb so as to protrude downward. The convex portion 4301 is provided with an intake port 430Yb1 which is a through-hole that penetrates the second frame 430Yb in the Z direction. The discharge port 430Ya1 and the intake port 430Yb1 communicate with the outside of the toner cartridge 430Y.

[0089] The outlet 430Ya1 and the inlet 430Yb1 are preferably provided on all sides of the toner cartridge 430Y except for the left and right sides. In other words, the outlet 430Ya1 and the inlet 430Yb1 are preferably provided on all sides of the toner cartridge 430Y except for the side facing the Y direction, which is the direction in which the toner cartridges 430Y, 430M, 430C, and 430K are aligned. This allows the gaps Gym, Gmc, and Gck in the Y direction between the toner cartridges 430Y, 430M, 430C, and 430K to be narrowed, as shown in FIG. 3(a). As a result, the width of the toner cartridges 430Y, 430M, 430C, and 430K in the Y direction can be increased, thereby increasing the toner capacity that can be accommodated in the toner cartridges 430Y, 430M, 430C, and 430K.

[0090] Gap Gym is the gap in the Y direction between toner cartridge 430Y and toner cartridge 430M. Gap Gmc is the gap in the Y direction between toner cartridge 430M and toner cartridge 430C. Gap Gck is the gap in the Y direction between toner cartridge 430C and toner cartridge 430K.

[0091] As shown in FIG. 3(a), the cartridge holder 51 is provided with a positioning portion 51b that engages with the protrusion 4301. In this embodiment, the positioning portion 51b is a recess formed in the cartridge holder 51, and a discharge hole 514a through which air sent from the pump unit 1 is discharged is formed in the bottom surface of the positioning portion 51b. The toner cartridge 430Y is positioned relative to the cartridge holder 51 by the engagement of the protrusion 4301 with the positioning portion 51b. At this time, an intake port 430Yb1 provided in the protrusion 4301 of the toner cartridge 430Y communicates with the fourth pipe 6R2 of the pump unit 80Y.

[0092] Furthermore, the discharge port 430Ya1 provided in the first frame 430Ya of the toner cartridge 430Y opens upstream in the X direction. That is, the discharge port 430Ya1 opens in the same direction as the mounting direction of the toner cartridge 430Y into the cartridge holder 51. Therefore, when the toner cartridge 430Y is mounted upstream in the X direction into the cartridge holder 51, the discharge port 430Ya1 can be easily engaged with the receiving port 51aY of the cartridge holder 51 so as to communicate with each other.

[0093] The positions are not limited to those described above, and the outlet 430Ya1 may be provided on the bottom surface 4300Yb or the top surface of the toner cartridge 430Y, and the inlet 430Yb1 may be provided on the back surface 4300Ya or the top surface of the toner cartridge 430Y. If there is sufficient space in the device main body 72, the outlet 430Ya1 and the inlet 430Yb1 may be provided on both the left and right sides of each side surface of the toner cartridge 430Y.

[0094] The toner cartridge 430Y may also be provided with a sealing member (not shown) that seals the discharge port 430Ya1. The sealing member may be a seal, a shutter, or the like. When the toner cartridge 430Y is not attached to the cartridge holder 51, the sealing member seals the discharge port 430Ya1, thereby preventing toner in the toner storage chamber 430Yc from leaking out of the toner cartridge 430Y. If the sealing member is a seal, the sealing member is removed from the rear surface 4300Ya of the toner cartridge 430Y when the toner cartridge 430Y is attached to the cartridge holder 51. If the sealing member is a shutter, the sealing member is moved relative to the rear surface 4300Ya of the toner cartridge 430Y to open the discharge port 430Ya1 when the toner cartridge 430Y is attached to the cartridge holder 51.

[0095] As shown in FIG. 8(a), a label 430Ys is provided on the front surface 4304 of the toner cartridge 430Y. The label 430Ys indicates the color of the toner contained in the toner cartridge 430Y. The label 430Ys is omitted in figures other than FIG. 8(a). The label 430Ys may indicate how to mount the toner cartridge 430Y in the cartridge holder 51 or information related to the toner cartridge 430Y. For example, the label 430Ys may indicate the amount of toner that can be contained in the toner cartridge 430Y, the expiration date of the toner, how to store the toner cartridge 430Y, how to remove the sealing member described above, etc.

[0096] As shown in FIGS. 9(a) to 10(b), a discharge pipe 85Y is disposed inside the toner storage chamber 430Yc. The discharge pipe 85Y has an inlet 85Ya that opens downward in the direction of gravity and an outlet 85Yb that opens rearward, i.e., upstream in the X direction, and communicates with the discharge port 430Ya1 of the toner cartridge 430Y and the outside of the toner cartridge 430Y. The outlet 85Yb is located above the inlet 85Ya. The discharge pipe 85Y has a first pipe portion 85Y1 that is provided with the inlet 85Ya and extends in the Z direction, and a second pipe portion 85Y2 that is provided with the outlet 85Yb connected to the discharge port 430Ya1 and extends in the X direction, and is bent midway. In this manner, the discharge pipe 85Y connects the inlet 85Ya and the outlet 85Yb. The inlet 85Ya is disposed opposite the lowermost portion 83Yb of the filter 83Y with a gap in the direction of gravity. The inlet 85Ya is preferably located close to the filter 83Y. The discharge pipe 85Y in this embodiment is made of a resin material, but may be made of paper, rubber, or the like.

[0097] [Toner transport mechanism] Next, the mechanism by which the toner contained in the toner storage chamber 430Yc of the toner cartridge 430Y is transported to the developing container 43Y of the process cartridge PY will be described. As shown in FIGS. 3(b) and 6, when the fourth pump 3R2 of the pump unit 1 operates, air is discharged from the discharge hole 514a via the fourth pipe 6R2 and the flow path of the cartridge holder 51. The air discharged upward from the discharge hole 514a is taken into the air chamber 430Yd through the intake port 430Yb1 of the toner cartridge 430Y, as shown in FIG. 9(a). This air then fills the air chamber 430Yd, passes through the filter 83Y, and flows into the toner storage chamber 430Yc.

[0098] The air that flows into the toner storage chamber 430Yc penetrates between the particles of toner T, fluidizing the toner T. The air flowing in from the pump unit 80Y creates a positive pressure inside the toner cartridge 430Y, and the air passes through the discharge pipe 85Y and attempts to exit the toner cartridge 430Y from the discharge port 430Ya1. At this time, the toner T in the toner storage chamber 430Yc is moved along with the air through the discharge pipe 85Y and is discharged from the discharge port 430Ya1 to the outside of the toner cartridge 430Y. In other words, the discharge pipe 85Y guides the toner in the toner storage chamber 430Yc together with the air from the inlet 85Ya to the discharge port 430Ya1.

[0099] The toner T discharged from the discharge port 430Ya1 enters the upstream end 62Yu of the supply pipe 62Y through the receiving port 51aY of the cartridge holder 51. The toner T is then transported inside the supply pipe 62Y by the air that has flowed into the supply pipe 62Y together with the toner T, and is replenished from the downstream end 62Yd of the supply pipe 62Y to the developing container 43Y of the process cartridge PY.

[0100] 5(b), rotatable agitation members SY1 and SY2 for agitating the toner in the developer container 43Y are provided inside the developer container 43Y. Similarly, agitation members SY1 and SY2, agitation members SM1 and SM2, agitation members SC1 and SC2, and agitation members SK1 and SK2 are provided inside the developer containers 43M, 43C, and 43K, respectively.

[0101] The toner in the developer container 43Y is leveled and transported in the Y direction by the rotation of the agitating members SY1 and SY2. In this embodiment, the supply pipes 62Y, 62M, 62C, and 62K are connected to the centers of the developer units 9Y, 9M, 9C, and 9K (developer containers 43Y, 43M, 43C, and 43K) in the Y direction, respectively. This reduces the variation in the time required for the rotation of the agitating members SY1 and SY2 to level the toner agent surfaces of each color in the developer units 9Y, 9M, 9C, and 9K corresponding to the four colors of toner. Note that in this embodiment, these agitating members are composed of a rotating shaft and a sheet member fixed to the rotating shaft, but this is not limiting. For example, the agitating members may be composed of a screw configured to transport the toner in the developer container along the Y direction.

[0102] Since not only toner T but also air flows into the developer container 43Y, the internal pressure within the developer container 43Y increases. For this reason, in this embodiment, as shown in FIGS. 3(a) and 4(b), a through-hole (not shown) is provided in the upper surface of the developer container 43Y, and the through-hole is covered with an exhaust filter PfY. The exhaust filter PfY is made of a nonwoven fabric or the like and is configured to allow air to pass through but restrict the passage of toner. As a result, the toner that has flowed into the developer container 43Y is restricted from being discharged to the outside by the exhaust filter PfY and remains within the developer container 43Y. Meanwhile, at least a portion of the air that has flowed into the developer container 43Y passes through the exhaust filter PfY and is discharged to the outside of the developer container 43Y. This suppresses an increase in the internal pressure of the developer container 43Y, allowing toner to be smoothly replenished to the developer container 43Y.

[0103] Similarly, exhaust filters PfM, PfC, PfK and through holes (not shown) covered by the exhaust filters PfM, PfC, PfK are provided on the upper surfaces of the developing containers 43M, 43C, 43K.

[0104] The number of these exhaust filters and through holes is not limited to one, and a plurality of exhaust filters and through holes may be provided in the developing container 43Y. By providing a plurality of exhaust filters and through holes for one developing container, an increase in the internal pressure in the developing container can be efficiently suppressed.

[0105] As described above, the toner contained in the toner cartridge 430Y is transported to the developer container 43Y together with air, and replenished to the developer container 43Y. In a configuration in which the direction of the transport path changes midway, or in which the transport path differs depending on the toner color, as in the case of the supply pipes 62Y, 62M, 62C, and 62K of this embodiment, it is preferable to transport the toner using air. By transporting the toner using air, the design freedom of the toner transport path is improved, and components such as screws for transporting the toner are no longer necessary, thereby reducing the number of parts and lowering costs.

[0106] In this embodiment, by providing the air chamber 430Yd, which is a tightly sealed space, between the discharge hole 514a and the filter 83Y, the air discharged from the discharge hole 514a is efficiently directed toward the filter 83Y without dispersing outside the toner cartridge 430Y. For example, if the toner cartridge 430Y is subjected to vibration or left unused for a long period of time, causing the toner T in the toner storage chamber 430Yc to aggregate, the pressure required to pass through the filter 83Y and flow into the toner storage chamber 430Yc increases. Even in such a case, by continuing to send air from the pump unit 1 to the air chamber 430Yd and increasing the pressure (air pressure) within the air chamber 430Yd, it becomes possible to send air into the toner storage chamber 430Yc through the filter 83Y.

[0107] Furthermore, by providing the air chamber 430Yd, it is sufficient for the pump unit 1 to have the performance to generate pressure that allows it to continue sending air into the air chamber 430Yd until the pressure reaches the pressure required for air to pass through the filter 83Y into the toner-accommodating chamber 430Yc. Therefore, since there are no special requirements for the air discharge speed or discharge amount, it is possible to employ a small pump unit, which contributes to the miniaturization of the device.

[0108] [Pump unit layout] Next, the layout of the pump unit 1 will be described in detail. As shown in Figures 6 and 7, the first rotating shaft 4Ls of the first dual-shaft motor 4L and the second rotating shaft 4Rs of the second dual-shaft motor 4R are arranged coaxially. That is, as shown in Figure 1, the first rotating shaft 4Ls and the second rotating shaft 4Rs are arranged on the same rotation axis AL1. This allows the pump unit 1 to be reduced in size in the X and Z directions.

[0109] Furthermore, the first double-shaft motor 4L, the first pump 3L1, the first drive transmission unit 5L1, the second drive transmission unit 5L2, and the second pump 3L2 are arranged side by side in the Y direction. Similarly, the second double-shaft motor 4R, the third pump 3R1, the third drive transmission unit 5R1, the fourth drive transmission unit 5R2, and the fourth pump 3R2 are arranged side by side in the Y direction. Furthermore, the first pump 3L1, the second pump 3L2, the third pump 3R1, and the fourth pump 3R2 are aligned in the Y direction, which is the first direction. This allows the size of the pump unit 1 to be reduced in the X and Z directions.

[0110] By miniaturizing the pump unit 1 in the X and Z directions as described above, the pump unit 1 can be disposed between the laser beam LC that exposes the photosensitive drum 44C and the laser beam LK that exposes the photosensitive drum 44K in the X direction, as shown in FIG. 1. The laser beam LC is an example of a second optical path for exposing the photosensitive drum 44C, and the laser beam LK is an example of a first optical path for exposing the photosensitive drum 44K. The pump unit 1 can also be disposed between the laser scanner LB and the developing unit 9K in the Z direction, which is a third direction perpendicular to both the X and Y directions. In particular, as shown in FIG. 5(b), when the developing units 9Y, 9M, 9C, and 9K are disposed so as to move away from the laser scanner LB in the Z direction as they move toward the X direction, a space is created between the laser scanner LB and the developing unit 9K. Disposing the pump unit 1 in this space improves the space efficiency of the image forming apparatus 100.

[0111] Furthermore, the pump unit 1 is disposed farther from the fixing unit 21 in the X direction than the developing units 9Y, 9M, and 9C. In other words, the developing unit 9Y is disposed closer to the fixing unit 21 in the X direction than the developing unit 9M, and the pump unit 1 is disposed farther from the fixing unit 21 in the X direction than the developing unit 9Y. The fixing unit 21 generates heat during the fixing operation of fixing the toner image to the sheet. Therefore, by disposing the pump unit 1 farther from the fixing unit 21, it is possible to suppress temperature increases in the first double-shaft motor 4L and the second double-shaft motor 4R of the pump unit 1. Furthermore, the pump unit 1 creates an airflow in the image forming unit 500, thereby reducing the temperature of the air around the image forming unit 500.

[0112] Additionally, the intake ports (430Yb1) of the cartridges that take in air sent from each pump are also arranged side by side in the Y direction. This allows the air path from each pump (for example, the first pump 3L1) to each intake port (for example, 430Yb1) to be shortened, improving the air transport efficiency and reducing the space occupied by the pump unit 1 and the toner cartridges 430Y, 430M, 430C, and 430K.

[0113] Furthermore, as described above, the first pump 3L1 and the second pump 3L2 are selectively driven by a single drive source, the first double-shaft motor 4L. Similarly, the third pump 3R1 and the fourth pump 3R2 are selectively driven by a single drive source, the second double-shaft motor 4R. This allows for a reduction in the number of drive sources in the pump unit 1, resulting in space savings and cost reductions.

[0114] As shown in FIGS. 1 and 5(b), the developing units 9Y, 9M, 9C, and 9K and the toner cartridges 430Y, 430M, 430C, and 430K are arranged to overlap an imaginary line VL1 extending in the X direction when viewed in the Y direction. The pump unit 1 is arranged above the imaginary line VL1. Furthermore, the toner cartridges 430Y, 430M, 430C, and 430K are positioned closer to the developing unit 9K than the developing unit 9C in the X direction, and the pump unit 1 is positioned to overlap the developing unit 9K when viewed in the Z direction. This allows the pump unit 1 to be arranged close to the toner cartridges 430Y, 430M, 430C, and 430K and the developing unit 9K. This reduces pressure loss when sending air between the pump unit 1 and the toner cartridges 430Y, 430M, 430C, and 430K, allowing the pump unit 1 and the image forming unit 500 to be made smaller.

[0115] As described above, by arranging the pump unit 1 and its peripheral configuration, it is possible to provide a new form of image forming apparatus including the pump unit 1. Furthermore, it is possible to reduce the size of the pump unit 1 and the image forming apparatus 100.

[0116] <Other embodiments> In the present embodiment, the first pump 3L1 is configured to operate when the first rotating shaft 4Ls rotates in the first rotation direction R1, but this is not limiting. Which pump operates when the first rotating shaft 4Ls or the second rotating shaft 4Rs rotates in which direction may be set as appropriate.

[0117] In addition, in this embodiment, the first dual-shaft motor 4L, the first clutch unit 5dL1, the first eccentric shaft 5eL1, the second clutch unit, and the second eccentric shaft 5eL2 are arranged side by side in the Y direction, but are not limited to this. For example, the first dual-shaft motor 4L, the first clutch unit 5dL1, the first eccentric shaft 5eL1, the second clutch unit, and the second eccentric shaft 5eL2 may be arranged side by side in the X direction or the Z direction.

[0118] In this embodiment, the first rotating shaft 4Ls of the first dual-shaft motor 4L and the second rotating shaft 4Rs of the second dual-shaft motor 4R are arranged coaxially, but this is not limiting. For example, the first rotating shaft 4Ls and the second rotating shaft 4Rs do not necessarily have to be arranged coaxially, and they may be slightly misaligned in the X or Z direction.

[0119] Furthermore, the above-described pumps are not limited to diaphragm pumps, but may be reciprocating pumps such as piston pumps and plunger pumps. Furthermore, the pumps may be non-positive-displacement pumps such as centrifugal pumps, propeller pumps, and viscous pumps. In the pump unit 1, the first pump 3L1 and the second pump 3L2 are driven by a single first double-shaft motor 4L, but this is not limiting. For example, the first pump 3L1 and the second pump 3L2 may be driven by two drive sources instead of a single drive source.

[0120] In addition, in the present embodiment, the pump unit 1 is disposed above the developing unit 9K, but this is not limiting. For example, the pump unit 1 may be disposed below the developing unit 9K. In this case, the pump unit 1 may be disposed so as not to overlap with the toner cartridges 430Y, 430M, 430C, and 430Y when viewed in the Z direction.

[0121] The disclosure of the present embodiment also includes the following configuration examples and method examples. (Configuration 1) In an image forming apparatus for forming an image on a sheet, an apparatus main body having a first developing unit having a first developing container configured to contain a first toner and a first developing roller that carries the first toner, and a second developing unit having a second developing container configured to contain a second toner and a second developing roller that carries the second toner; a first toner container that contains the first toner and is detachably supported by the apparatus main body, the first toner container being configured to be able to replenish the first toner together with air to the first developing container; a second toner container that contains the second toner and is detachably supported by the apparatus main body, the second toner container being configured to be able to replenish the second toner together with air to the second developing container, and being aligned with the first toner container in a first direction; a pump unit having a first pump for transporting air to the first toner container and a second pump for transporting air to the second toner container, the first pump and the second pump are operated by a single driving source and are aligned in the first direction; An image forming apparatus characterized by: (Configuration 2) the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction; 2. The image forming apparatus according to claim 1, (Configuration 3) the first toner container and the second toner container are provided at positions closer to the first developing unit than the second developing unit in the second direction; the pump unit is provided at a position overlapping with the first developing unit when viewed in a third direction perpendicular to both the first direction and the second direction; 3. The image forming apparatus according to configuration 2. (Configuration 4) the pump unit is disposed above the first developing unit; 4. The image forming apparatus according to configuration 3. (Configuration 5) The pump unit comprises: a motor as the drive source, the motor having a rotation shaft that is rotatable about a rotation axis in a first rotation direction and a second rotation direction opposite to the first rotation direction, the rotation shaft having a first end on one side in the direction of the rotation axis and a second end on the other side; a first drive transmission unit that can transition between a first transmission state in which drive is transmitted from the first end of the rotary shaft to the first pump and a first non-transmission state in which drive is not transmitted from the first end to the first pump; a second drive transmission unit that can transition between a second transmission state in which drive is transmitted from the second end of the rotating shaft to the second pump and a second non-transmission state in which drive is not transmitted from the second end to the second pump, the first drive transmission unit is configured to operate the first pump by transitioning to the first transmission state when the rotating shaft rotates in the first rotation direction, and to not operate the first pump by transitioning to the first non-transmission state when the rotating shaft rotates in the second rotation direction, the second drive transmission unit is configured to transition to the second non-transmission state when the rotating shaft rotates in the first rotation direction, thereby not operating the second pump, and to transition to the second transmission state when the rotating shaft rotates in the second rotation direction, thereby operating the second pump. 5. The image forming apparatus according to any one of configurations 1 to 4. (Configuration 6) the motor, the first pump, the second pump, the first drive transmission unit, and the second drive transmission unit are arranged side by side in the first direction. 6. The image forming apparatus according to configuration 5. (Configuration 7) The first pump and the second pump are diaphragm pumps. 7. The image forming apparatus according to configuration 5 or 6. (Configuration 8) the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction, the device body has a fixing unit that applies heat and pressure to the toner image transferred onto the sheet to fix it to the sheet; the second developing unit is disposed at a position closer to the fixing unit than the first developing unit in the second direction; the pump unit is disposed at a position farther from the fixing unit than the second developing unit in the second direction. 8. The image forming apparatus according to any one of configurations 1 to 7. (Configuration 9) the first developing unit, the second developing unit, and the pump unit are aligned in a second direction perpendicular to the first direction; 9. The image forming apparatus according to any one of configurations 1 to 8. (Configuration 10) the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction, When viewed in the first direction, the first developing unit, the second developing unit, the first toner container, and the second toner container are arranged so as to overlap one imaginary line extending in the second direction; The pump unit is disposed above the imaginary line. 10. The image forming apparatus according to any one of configurations 1 to 9. (Configuration 11) the device main body includes a first photoconductor that carries an electrostatic latent image to be developed by the first developing roller, a second photoconductor that carries an electrostatic latent image to be developed by the second developing roller, and an exposure unit that exposes the first photoconductor and the second photoconductor; the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction, the pump unit is disposed between a first optical path through which the exposure unit exposes the first photosensitive member and a second optical path through which the exposure unit exposes the second photosensitive member in the second direction. 11. The image forming apparatus according to any one of configurations 1 to 10. (Configuration 12) the device main body includes a first photoconductor that carries an electrostatic latent image to be developed by the first developing roller, a second photoconductor that carries an electrostatic latent image to be developed by the second developing roller, and an exposure unit that exposes the first photoconductor and the second photoconductor; the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction, the pump unit is disposed between the exposure unit and the first developing unit in a third direction perpendicular to both the first direction and the second direction; 12. The image forming apparatus according to any one of configurations 1 to 11. (Configuration 13) In an image forming apparatus for forming an image on a sheet, an apparatus main body having a first developing unit having a first developing container configured to contain a first toner and a first developing roller that carries the first toner, and a second developing unit having a second developing container configured to contain a second toner and a second developing roller that carries the second toner; a first toner container that contains the first toner and is detachably supported by the apparatus main body, the first toner container being configured to be able to replenish the first toner together with air to the first developing container; a second toner container that contains the second toner and is detachably supported by the apparatus main body, the second toner container being configured to be able to replenish the second toner together with air to the second developing container, and being aligned with the first toner container in a first direction; a pump unit having a first pump for transporting air to the first toner container and a second pump for transporting air to the second toner container, the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction, the first toner container and the second toner container are provided at positions closer to the first developing unit than the second developing unit in the second direction; the pump unit is provided at a position overlapping with the first developing unit when viewed in a third direction perpendicular to both the first direction and the second direction; An image forming apparatus characterized by: (Configuration 14) the pump unit is disposed above the first developing unit; 14. The image forming apparatus according to claim 13, [Explanation of symbols]

[0122] 1: Pump unit / 3L1: First pump / 3L2: Second pump / 4L: Drive source, motor (first double-shaft motor) / 4La: First protrusion / 4Lb: Second protrusion / 4Ls: Rotating shaft (first rotating shaft) / 5L1: First drive transmission part / 5L2: Second drive transmission part / 9C: Second developing unit (developing unit) / 9K: First developing unit (developing unit) / 21: Fixing unit / 43C: Second developing container (developing container) / 43K: First developing container (developing container) / 44C: Second photosensitive body (photosensitive drum) / 44K: First photosensitive body (photosensitive drum) (system) / 46C: second developing roller (developing roller) / 46K: first developing roller (developing roller) / 72: device main body / 100: image forming device / 430C: second toner container (toner cartridge) / 430K: first toner container (toner cartridge) / AL1: rotation axis / LB: exposure unit (laser scanner) / LC: second optical path (laser light) / LK: first optical path (laser light) / R1: first rotation direction / R2: second rotation direction / VL1: virtual line / X: second direction (direction) / Y: first direction (direction) / Z: third direction (direction)

Claims

1. In an image forming apparatus for forming an image on a sheet, an apparatus main body having a first developing unit having a first developing container configured to contain a first toner and a first developing roller that carries the first toner, and a second developing unit having a second developing container configured to contain a second toner and a second developing roller that carries the second toner; a first toner container that contains the first toner and is detachably supported by the apparatus main body, the first toner container being configured to be able to replenish the first toner together with air to the first developing container; a second toner container that contains the second toner and is detachably supported by the device main body, the second toner container being configured to be able to replenish the second toner together with air to the second developing container, and being aligned with the first toner container in a first direction; a pump unit having a first pump for transporting air to the first toner container and a second pump for transporting air to the second toner container, the first pump and the second pump are operated by a single driving source and are aligned in the first direction; An image forming apparatus characterized by:

2. the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction; 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

3. the first toner container and the second toner container are provided at positions closer to the first developing unit than the second developing unit in the second direction; the pump unit is provided at a position overlapping the first developing unit when viewed in a third direction perpendicular to both the first direction and the second direction; 3. The image forming apparatus according to claim 2, wherein the image forming apparatus is a recording medium.

4. the pump unit is disposed above the first developing unit; 4. The image forming apparatus according to claim 3, wherein the image forming apparatus is a recording medium.

5. The pump unit comprises: a motor as the drive source, the motor having a rotation shaft that is rotatable about a rotation axis in a first rotation direction and a second rotation direction opposite to the first rotation direction, the rotation shaft having a first end on one side in the direction of the rotation axis and a second end on the other side; a first drive transmission unit that can transition between a first transmission state in which drive is transmitted from the first end of the rotary shaft to the first pump and a first non-transmission state in which drive is not transmitted from the first end to the first pump; a second drive transmission unit that can transition between a second transmission state in which drive is transmitted from the second end of the rotary shaft to the second pump and a second non-transmission state in which drive is not transmitted from the second end to the second pump, the first drive transmission unit is configured to transition to the first transmission state when the rotating shaft rotates in the first rotational direction, thereby actuating the first pump, and to transition to the first non-transmission state when the rotating shaft rotates in the second rotational direction, thereby not actuating the first pump, the second drive transmission unit is configured to transition to the second non-transmission state when the rotating shaft rotates in the first rotation direction, thereby not operating the second pump, and to transition to the second transmission state when the rotating shaft rotates in the second rotation direction, thereby operating the second pump.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

6. the motor, the first pump, the second pump, the first drive transmission unit, and the second drive transmission unit are arranged side by side in the first direction.

6. The image forming apparatus according to claim 5,

7. the first pump and the second pump are diaphragm pumps; 6. The image forming apparatus according to claim 5,

8. the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction, the device body has a fixing unit that applies heat and pressure to the toner image transferred onto the sheet to fix it to the sheet; the second developing unit is disposed at a position closer to the fixing unit than the first developing unit in the second direction; the pump unit is disposed at a position farther from the fixing unit than the second developing unit in the second direction.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

9. the first developing unit, the second developing unit, and the pump unit are aligned in a second direction perpendicular to the first direction; 9. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

10. the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction, When viewed in the first direction, the first developing unit, the second developing unit, the first toner container, and the second toner container are arranged so as to overlap one imaginary line extending in the second direction, The pump unit is disposed above the imaginary line.

9. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

11. the device main body includes a first photoconductor that carries an electrostatic latent image to be developed by the first developing roller, a second photoconductor that carries an electrostatic latent image to be developed by the second developing roller, and an exposure unit that exposes the first photoconductor and the second photoconductor; the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction, the pump unit is disposed between a first optical path through which the exposure unit exposes the first photosensitive member and a second optical path through which the exposure unit exposes the second photosensitive member in the second direction.

9. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

12. the device main body includes a first photoconductor that carries an electrostatic latent image to be developed by the first developing roller, a second photoconductor that carries an electrostatic latent image to be developed by the second developing roller, and an exposure unit that exposes the first photoconductor and the second photoconductor; the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction, the pump unit is disposed between the exposure unit and the first developing unit in a third direction perpendicular to both the first direction and the second direction; 9. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

13. In an image forming apparatus for forming an image on a sheet, an apparatus main body having a first developing unit having a first developing container configured to contain a first toner and a first developing roller that carries the first toner, and a second developing unit having a second developing container configured to contain a second toner and a second developing roller that carries the second toner; a first toner container that contains the first toner and is detachably supported by the apparatus main body, the first toner container being configured to be able to replenish the first toner together with air to the first developing container; a second toner container that contains the second toner and is detachably supported by the device main body, the second toner container being configured to be able to replenish the second toner together with air to the second developing container, and being aligned with the first toner container in a first direction; a pump unit having a first pump for transporting air to the first toner container and a second pump for transporting air to the second toner container, the first developing unit and the second developing unit are aligned in a second direction perpendicular to the first direction, the first toner container and the second toner container are provided at positions closer to the first developing unit than the second developing unit in the second direction; the pump unit is provided at a position overlapping the first developing unit when viewed in a third direction perpendicular to both the first direction and the second direction; An image forming apparatus characterized by:

14. the pump unit is disposed above the first developing unit; 14. The image forming apparatus according to claim 13.

Images