Image forming apparatus

Abstract

An image forming apparatus for transporting toner and a form of toner container used therein can be provided. [Solution] The invention comprises a first developing unit located above a first toner container and a second toner container, a second developing unit aligned with the first developing unit in a second direction intersecting a first direction and the direction of gravity, and located above the first toner container and the second toner container, a first passage through which the first toner passes, and a second passage through which the second toner passes, wherein the first toner is supplied from the first toner container to the first developing container via the first passage, and the second toner is supplied from the second toner container to the second developing container via the second passage.

Description

Technical Field

[0001] The present invention relates to an image forming apparatus and a toner container used therefor.

Background Art

[0002] In an electrophotographic image forming apparatus, a configuration is known in which a toner container detachable from the image forming apparatus is used to supply toner to a developing container in the image forming apparatus. Patent Document 1 discloses a configuration in which a supply pack is attached to the image forming apparatus, and toner can be easily supplied without replacing the developing container.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a new form of an image forming apparatus for transporting toner and a toner container used therefor.

Means for Solving the Problems

[0005] To solve the aforementioned problems, the image forming apparatus of the present invention comprises a first toner container for containing a first toner, a second toner container for containing a second toner, the second toner container being aligned with the first toner container in a first direction intersecting the direction of gravity, and an apparatus body configured such that the first toner container and the second toner container are detachably attached, the apparatus body having a rotatable first developing roller for carrying the first toner, and a first developing container for containing the first toner carried on the first developing roller, a first developing unit located above the first toner container and the second toner container, and a rotatable second developing unit for carrying the second toner A second developing unit having two developing rollers and a second developing container for containing a second toner supplied to the second developing roller, wherein the second developing unit is aligned with the first developing unit in a second direction intersecting the first direction and the direction of gravity, and is located above the first toner container and the second toner container, and has a first passage through which the first toner passes and a second passage through which the second toner passes, wherein the first toner is supplied from the first toner container to the first developing container via the first passage, and the second toner is supplied from the second toner container to the second developing container via the second passage. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a new form of an image forming apparatus for transporting toner and a toner container used therein. [Brief explanation of the drawing]

[0007] [Figure 1] This is a cross-sectional view of the image forming apparatus according to Example 1. [Figure 2] This is a perspective view of the image forming apparatus according to Example 1. [Figure 3] This is a perspective view of the toner container and image forming unit of the image forming apparatus according to Example 1. [Figure 4] This diagram shows the connection portion between the toner supply unit and the toner container according to Example 1. [Figure 5]This is a cross-sectional view of the toner container in the attached / detached state according to Example 1. [Figure 6] This is a top view showing the arrangement of the process cartridge and toner cartridge according to Example 1. [Figure 7] This diagram shows the linkage operation caused by the opening and closing of the front door according to Example 1. [Figure 8] This is a perspective view of the image forming apparatus according to Example 2. [Figure 9] This is a cross-sectional view of the toner supply unit according to Example 2. [Modes for carrying out the invention]

[0008] <First Embodiment> (Image forming apparatus) An image forming apparatus 1 according to the first embodiment of the present invention will be described with reference to Figure 1. The electrophotographic image forming apparatus of this embodiment is a full-color image forming apparatus equipped with four color process units. Figure 1 is a main cross-section of the image forming apparatus 1.

[0009] Image forming apparatus 1 is a full-color laser printer using an electrophotographic process, and is capable of forming full-color images on a recording medium S. Image forming apparatus 1 comprises process units PY, PM, PC, and PK (hereinafter referred to as each process unit P) and a main body 72. Each process unit P is arranged in alignment along a first direction X (first direction), and the toner colors contained inside are different from each other. The longitudinal direction of the process unit P is along a second direction Y (second direction) perpendicular to the first direction. Process units PY, PM, PC, and PK are referred to as the first process unit, second process unit, third process unit, and fourth process unit, respectively. The suffixes Y, M, C, and K represent toner colors. Y is yellow, M is magenta, C is cyan, and K is black. The same applies to process units other than P thereafter.

[0010] Each process unit P has an electrophotographic process element. Rotational driving force is transmitted to the process unit P from the drive output section (not shown) of the apparatus body 72, and a bias voltage (charging bias, development bias, etc.) is supplied from the bias application section (not shown) of the apparatus body 72.

[0011] As shown in Figure 1, each process unit P comprises drum units 8Y, 8M, 8C, and 8K (hereinafter referred to as each drum unit 8). Each drum unit 8 comprises a photosensitive drum 4Y, 4M, 4C, and 4K (hereinafter referred to as each photosensitive drum 4) and charging rollers 5Y, 5M, 5C, and 5K (hereinafter referred to as each charging roller 5) which act as process means on the photosensitive drum 4. Each photosensitive drum 4 is rotatably arranged such that the direction of its rotation axis is aligned with the second direction Y. The photosensitive drums 4Y, 4M, 4C, and 4K are referred to as the first photosensitive drum, second photosensitive drum, third photosensitive drum, and fourth photosensitive drum, respectively.

[0012] Each process unit P comprises developing units 9Y, 9M, 9C, 9K (hereinafter referred to as each developing unit 9), each having developing rollers 6Y, 6M, 6C, 6K (hereinafter referred to as each developing roller 6) for developing the electrostatic latent image on the corresponding photosensitive drum 4. Each developing unit 9 is aligned along a first direction X. These rotatably configured developing rollers 6Y, 6M, 6C, 6K are designated as the first developing roller, second developing roller, third developing roller, and fourth developing roller, respectively. The developing units 9Y, 9M, 9C, 9K are designated as the first developing unit, second developing unit, third developing unit, and fourth developing unit, respectively.

[0013] The developing unit 9Y has a developing container 3Y (first developing container) that contains yellow (Y) toner (first toner), and is configured so that the yellow (Y) toner is supplied to the surface of the photosensitive drum 4Y by a developing roller 6Y that carries the yellow (Y) toner.

[0014] The developing unit 9M has a developing container 3M (second developing container) that houses magenta (M) toner (second toner), and is configured such that the magenta (M) toner is supplied to the surface of the photosensitive drum 4M by a developing roller 6M that carries the magenta (M) toner.

[0015] The developing unit 9C has a developing container 3C (third developing container) that houses cyan (C) toner (third toner), and is configured such that the cyan (C) toner is supplied to the surface of the photosensitive drum 4C by a developing roller 6C that carries the cyan (C) toner.

[0016] The developing unit 9K has a developing container 3K (fourth developing container) that houses black (K) toner (fourth toner), and is configured such that the black (K) toner is supplied to the surface of the photosensitive drum 4K by a developing roller 6K that carries the black (K) toner.

[0017] In a third direction Z that intersects both the first direction X and the second direction Y, above the process unit P (photosensitive drum 4), a laser scanner unit LB (exposure unit) is provided. This laser scanner unit LB outputs laser light corresponding to image information.

[0018] Note that the third direction Z in this embodiment is a direction along the gravitational direction.

[0019] Hereinafter, the optical paths of the laser light directed at the photosensitive drums 4Y, 4M, 4C, 4K are respectively referred to as optical paths LY, LM, LC, LK (hereinafter, each optical path L or optical path L is also denoted as such). And the laser light passes through the exposure windows 10Y, 10M, 10C, 10K of the laser scanner unit LB and scans and exposes the surface of each photosensitive drum 4. Note that an LED exposure unit may be used instead of the laser scanner unit LB.

[0020] In the third direction Z, an intermediate transfer belt unit 11 is provided below the process unit P as a transfer member. This intermediate transfer belt unit 11 has a drive roller 14, a tension roller 13, and an assist roller 15, and a flexible transfer belt 12 is stretched across it.

[0021] Each photosensitive drum 4 has its lower surface in contact with the upper surface of the transfer belt 12. The contact areas between each photosensitive drum 4 and the transfer belt 12 form primary transfer sections 30Y, 30M, 30C, and 30K (hereinafter referred to as primary transfer sections 30). On the inside of the transfer belt 12, primary transfer rollers 16Y, 16M, 16C, and 16K (hereinafter referred to as transfer rollers 16) are provided facing the photosensitive drum 4.

[0022] The secondary transfer roller 17 is pressed against the drive roller 14 via the transfer belt 12. A secondary transfer portion 31 is formed at the contact point between the transfer belt 12 and the secondary transfer roller 17.

[0023] In the third direction Z, a feeding unit 18 is provided below the intermediate transfer belt unit 11. The feeding unit 18 includes a paper feed tray 19 for loading and storing recording media S, and a paper feed roller 20 for picking up and transporting the recording media S from the paper feed tray 19.

[0024] In Figure 1, the upper part of the main body 72 of the device is provided with a fixing unit 21 for fixing the toner image onto the recording medium S, and an discharge roller 22 for discharging the recording medium S with the fixed toner image to the discharge tray 23. The discharge roller 22 discharges the recording medium S in a direction along the first direction X.

[0025] In this embodiment, the downstream side in the discharge direction from which the recording material S is discharged toward the discharge tray 23 by the discharge roller 22 is the front side of the image forming apparatus 1, and the upstream side in the discharge direction is the rear side of the image forming apparatus 1.

[0026] In the third direction Z, a replenishment toner unit 40 is provided below the supply unit 18. The replenishment toner unit 40 can replenish the toner T contained in the toner cartridge 41 to the developing container 3 via the toner transport path 51.

[0027] The configuration of the toner container 41 will now be described. In the toner cartridge 41, the toner chamber (toner storage chamber) 41a in which the toner is stored and the air chamber 41b connected to the outside are separated by a filter 42. The filter 42 allows air to pass through but prevents and restricts the passage of toner. The toner chamber 41a is provided with a toner path 43 connecting the toner intake port 43a and the toner discharge port 43b. The outer circumference of the filter 42 is fixed to the frame.

[0028] Next, the toner transport process will be explained. Air is supplied from the air pump 50 located in the replenishment toner unit 40 to the air supply port 44 of the toner cartridge 41. The supplied air passes through the filter 42 and is supplied to the toner chamber 41a. The air supplied from the air supply port 44 is fluidized by mixing with the toner T. The fluidized toner T flows into the toner path 43 from the toner intake port 43a. The toner T passes through the toner transport path 51 and is supplied to the developing container 3.

[0029] Alternatively, a shaftless screw that rotates by receiving driving force from an actuator may be used instead of an air pump.

[0030] The replenishment toner unit 40 has a front cover 46 that can be opened and closed to cover an opening for accessing the toner cartridge 41. After opening the front cover 46, the user can reach their hand through the opening and pull out the toner container 41 by the handle 45 on the front side.

[0031] In the third direction Z, a feed option unit 60 is provided below the replenishment toner unit 40. The feed option unit 60 is provided with a paper feed tray 69 on which recording media S are loaded and stored, and a paper feed roller 70 that picks up the recording media S from the paper feed tray 69 and transports them.

[0032] The toner supply unit 40 is equipped with transport rollers 48 and transport guides 49 for transporting the recording medium S picked up in the feeding option unit 60 to the main body of the image forming apparatus 72.

[0033] (Image formation process) The image forming operation for creating a full-color image is as follows: Each photosensitive drum 4 is driven to rotate counterclockwise at a predetermined speed in Figure 1. The transfer belt 12 is driven to rotate in the forward direction (direction of arrow C in Figure 1) of the rotation of each photosensitive drum 4 at a speed corresponding to the rotation speed of each photosensitive drum 4.

[0034] In synchronization with the operation of the laser scanner unit LB, each process unit P uniformly charges the surface of each photosensitive drum 4 corresponding to each charging roller 5 to a predetermined polarity and potential. The laser scanner unit LB scans and exposes the charged surface of each photosensitive drum 4 with laser light L according to the image signal of each color. An electrostatic latent image corresponding to the image signal of each color is formed on the surface of each photosensitive drum 4.

[0035] The laser scanner unit LB exposes the photosensitive drum 4Y, and a first electrostatic latent image is formed on the photosensitive drum 4Y.

[0036] Similarly, the laser beams LY, LM, and LK emitted from the laser scanner unit LB expose the photosensitive drums 4M, 4C, and 4K. A second electrostatic latent image, a third electrostatic latent image, and a fourth electrostatic latent image are then formed on the photosensitive drums 4M, 4C, and 4K, respectively.

[0037] Toner is supplied to each photosensitive drum 4 by each developing roller 6, which is driven to rotate clockwise at a predetermined speed in Figure 1, thereby developing the electrostatic latent image on each photosensitive drum 4.

[0038] Through the electrophotographic image formation process described above, a yellow toner image is formed on the photosensitive drum 4Y of the process unit P. This yellow toner image is then primary transferred onto the transfer belt 12.

[0039] A magenta toner image is formed on the photosensitive drum 4M of the process unit PM through a similar process. Then, the magenta toner image is primary transferred onto the transfer belt 12 so as to be superimposed on the yellow toner image on the transfer belt 12.

[0040] A cyan toner image is formed on the photosensitive drum 4C of the process unit PC. Then, the cyan toner image is primary transferred onto the transfer belt 12 so as to be superimposed on the yellow and magenta toner images on the transfer belt 12.

[0041] A black toner image is formed on the photosensitive drum 4K of the process unit PK. Then, the black toner image is primary transferred onto the transfer belt 12 so as to be superimposed on the yellow, magenta, and cyan toner images on the transfer belt 12.

[0042] In this way, a full-color, unfixed toner image of four colors—yellow, magenta, cyan, and black—is formed on the transfer belt 12. Meanwhile, at a predetermined control timing, the recording media S are separated one by one from the paper tray 19 by the paper feed roller 20 and fed. The recording media S are then transported at a predetermined control timing to the secondary transfer section 31, which is the contact point between the secondary transfer roller 17 and the transfer belt 12. As the recording media S is transported through the secondary transfer section 31, the four-color superimposed toner image on the transfer belt 12 is transferred to the recording media S. The recording media S on which the toner image has been transferred is heated and pressurized by the fixing unit 21, thereby fixing the toner image to the recording media S. The recording media S on which the toner image has been fixed is then discharged to the discharge tray 23 by the discharge roller 22.

[0043] As shown in Figure 3, the image forming apparatus 1 has toner cartridges 41Y, 41M, 41C, and 41K (hereinafter referred to as each cartridge 41) that can be attached to and removed from the replenishment toner unit 40. Each cartridge 41 is aligned along the second direction Y. That is, each toner cartridge 41 is aligned in a direction that intersects with the first direction X in which each developing unit 9 is aligned. In this embodiment, direction X and direction Y are orthogonal. The toner cartridges 41Y, 41M, 41C, and 41K will also be referred to as the first cartridge (first toner container), the second cartridge (second toner container), the third cartridge (third toner container), and the fourth cartridge (fourth toner container), respectively.

[0044] Figure 2 is a perspective view showing the image forming apparatus 1 with the front door 72b of the main body 72 and the front cover 46 of the replenishment toner unit 40 open.

[0045] The front door 72b is configured to be movable between a closed position (see Figure 1) that closes the opening of the front-facing device body 72 and an open position (see Figure 2) that opens the opening.

[0046] The process unit P is held in the process cartridge tray 35, as shown in Figure 2. The process cartridge tray 35 is configured to move between the inside and outside of the main body of the apparatus 72.

[0047] Figure 2 shows the process cartridge tray 35 in the state where it has been pulled out from the main unit 72 of the device. When the process cartridge tray 35 is pulled out to the outside of the main unit 72 of the device, the user can replace the process cartridge P.

[0048] Each toner cartridge 41 is mounted on the front side of the replenishment toner unit 40 so that it can be accessed by the user when the front cover 46 is opened. That is, as shown in Figure 2, the toner cartridges 41 of each color are arranged in a second direction Y and are configured to be detachable from the main body of the device 72 along a first direction X. The direction of the arrow in direction X is the detachment direction for removing the toner cartridge 41. The opposite direction of the arrow in direction X is the installation direction for installing the toner cartridge 41. The toner cartridges 41 are configured to be detachable in this way.

[0049] The toner transport mechanism and toner transport path from each toner cartridge 41 to the corresponding developing container 3 of each process unit P will be explained using Figures 3, 4, and 5(a).

[0050] Figure 3 is a perspective view showing the replenishment toner unit 40 with each toner cartridge 41 installed, each process cartridge P mounted on the process cartridge tray 35 (Figure 2), and the toner transport path 51 connecting each toner cartridge 41 and each process cartridge P. Figure 4(a) is a perspective view showing the configuration of the toner transport mechanism with each toner cartridge 41 removed from the replenishment toner unit 40, and Figure 4(b) is a front view. Figure 5(a) is a cross-sectional view showing the toner cartridge 41.

[0051] As shown in Figures 3 and 4(a) and 4(b), pump units 50Y, 50M, 50C, and 50K (hereinafter referred to as each pump unit 50) are provided behind the replenishment toner unit 40. Each pump unit 50 is aligned in the second direction Y. Pump units 50Y, 50M, 50C, and 50K are designated as the first pump unit (first pump), the second pump unit (second pump), the third pump unit (third pump), and the fourth pump unit (fourth pump), respectively. Each pump unit 50 uses a positive displacement pump such as a reciprocating pump or a rotary pump. A reciprocating pump is a pump that performs suction and discharge by the reciprocating motion of a piston or plunger, and includes piston pumps, plunger pumps, and diaphragm pumps. A rotary pump is a pump that performs suction and discharge by the rotational motion of gears or a rotor, and includes gear pumps, screw pumps, and vane pumps. In this embodiment, a diaphragm pump is used. Furthermore, the four pump units (pumps) may be configured as a single pump unit. In this embodiment, each pump unit 50 is provided on the main body 72 of the device, but it may also be provided on each cartridge 41.

[0052] As shown in Figure 5(a), each cartridge 41 has exposed outlets 50aY, 50aM, 50aC, and 50aK (hereinafter referred to as each outlet 50a) on the rear side of the main body in the first direction X, through which the air generated (sent out) by each pump unit 50 is discharged. Each outlet 50a opens toward the first direction X.

[0053] Air discharged from each outlet 50a in the first direction X is supplied to the inside of each toner cartridge 41 through the air supply port 44 shown in Figure 5(a). The air supplied to the inside of each toner cartridge 41 is discharged to the outside along with the toner. The internal structure of each cartridge 41 will be described later.

[0054] The toner discharged along with air from the outlet of each cartridge 41 is received into the receiving ports 51aY, 51aM, 51aC, and 51aK of the replenishment toner unit 40 shown in Figures 3 and 5(a). The receiving ports 51aY, 51aM, 51aC, and 51aK will be referred to as receiving ports 51a below.

[0055] The toner received through each receiving port 51a is received into toner transport paths 51Y, 51M, 51C, and 51K. The toner transport paths 51Y, 51M, 51C, and 51K will hereafter be referred to as toner transport paths 51. They may also be called the first passage, second passage, third passage, and fourth passage, respectively. Each toner transport path is made of a flexible tube that can be bent.

[0056] In this way, the output port of each cartridge 41 is connected to each toner transport path 51.

[0057] Each toner transport path 51 extends to each developing container 3 and is connected to developing containers 3Y, 3M, 3C, and 3K respectively (Figure 3). In each toner transport path 51, the direction in which the toner is transported will be referred to as the toner transport direction.

[0058] Each inlet 51a opens toward a first direction X, which is the direction in which each developing container unit 9 is lined up. The direction in which each inlet 51a opens is the same as the direction in which each outlet 50a opens, but the flow direction is opposite.

[0059] The toner received from each inlet 51a is discharged from each toner cartridge 41 along with air. The toner is then transported through each toner transport path 51 from the inlet 51a to the downstream ends 51bY, 51bM, 51bC, and 51bK (hereinafter referred to as each downstream end 51b) and supplied to each process unit P.

[0060] Each downstream end 51b of each toner transport path 51 is connected to the end of each developing unit 9 in the second direction Y. Specifically, the downstream end 51bY of the toner transport path 51Y is connected to the LE side end of the developing container 3Y. The developing container 3Y is part of the process unit PY. As shown in Figure 3, the LE side is the downstream direction in which arrow Y is pointed, and the RE side refers to the upstream side in arrow Y.

[0061] The same applies to the downstream end 51bM of the toner transport path 51M, the downstream end 51bC of the toner transport path 51C, and the downstream end 51bK of the toner transport path 51K. The downstream ends 51bM, 51bC, and 51bK are connected to the LE-side ends of the developing containers 3M, 3C, and 3K, respectively. By minimizing the difference in length of each toner transport path 51, the difference in pressure loss due to the difference in length can be reduced. Furthermore, by reducing the difference in pressure loss, the difference in the amount of toner transported for each toner becomes smaller, so the control of the pump 50 can be easily configured without making differences for each toner color.

[0062] Next, the arrangement of the toner cartridge 41Y will be explained using Figures 3 and 6. Figure 6 is a view of the toner cartridge 41 and the process unit P from the Z direction.

[0063] As shown in Figure 3, the toner cartridges 41 and each process unit P (each developing unit 9) are arranged so that their longitudinal directions are perpendicular to each other. In other words, when viewed in direction Z, at least a portion of the multiple toner cartridges 41 are arranged to overlap with each developing unit 9. It can also be said that when viewed in direction Z, at least a portion of the multiple developing units 9 are arranged to overlap with each toner cartridge 41.

[0064] By arranging each toner cartridge 41 in this manner, the four toner cartridges 41 can be inserted and removed from the X direction, which is the direction in which the recording material S is ejected.

[0065] The longitudinal direction of the process unit P is the Y direction. As shown in Figure 1, the rotation axes of the photosensitive drum 4 and the developing rollers 6 are also in the Y direction. Therefore, the transport direction of the recording material is the X direction when viewed from the Z direction. The rotation axes of the four developing rollers 6 may also be called the first rotation axis, second rotation axis, third rotation axis, and fourth rotation axis, respectively.

[0066] Here, the longitudinal direction of the toner cartridge 41 is aligned with the X direction, and as shown in Figure 4, the ejection port 50a and the receiving port 51a are also positioned to open along the X direction. Therefore, the insertion and removal direction of the toner cartridge 41 is also along the X direction. It is also advisable to provide a guide shape on the replenishment toner unit 40 to support the insertion and removal of the toner cartridge 41.

[0067] In this way, when removing the recording material S from the output tray 23, the user can access it from the X direction on the front of the main unit. Similarly, when replacing the toner cartridge 41, the user can directly access each color toner cartridge 41. Thus, the user can access both the recording material S and the toner cartridge 41 from the same direction, resulting in excellent usability.

[0068] Furthermore, the paper feed tray 19 shown in Figure 1 can also be accessed by the user from the X direction on the front of the unit. In other words, this configuration allows the user to access the paper feed, paper output, and toner cartridge from the same direction, resulting in good usability.

[0069] Next, the arrangement of each toner transport path 51 will be described.

[0070] The toner transport path 51, which receives toner from the receiving port 51a corresponding to each toner cartridge 41 in Figure 4, is gathered at one end in the second direction Y, as shown in Figures 3 and 6, and is then connected to the upper process unit P.

[0071] One end of this second direction Y will be referred to as the first end of the device body. The other end on the opposite side will be referred to as the second end of the device body. The side of the device body where the first end is located will be referred to as the first end side, and the side of the device body where the second end is located will be referred to as the second end side.

[0072] Since the toner transport path 51 connecting the replenishment toner unit 40 and the main unit 72 is consolidated into a single bundle, the number of parts (not shown) that hold them inside the main unit 72 can be reduced. In other words, the configuration of the main unit 72 can be simplified.

[0073] A connection part may be provided in the toner transport path 51 so that it can be separated between the toner supply unit 40 and the main unit 72 of the device. In this way, the toner supply unit 40 can be attached and detached while the toner transport path 51 is separated at the connection part.

[0074] (Connection between the process cartridge and the toner transport path) Figure 7 illustrates the operation of the connection between the process cartridge P and the toner transport path 51. Figure 7(a) shows the front door 72b in the closed position, and Figure 7(b) shows the front door 72b in the open position.

[0075] The toner transport path 51 is supported by a vertically moving member 75. The vertically moving member 75 is pressed downward by a sliding member 74. The toner transport path 51 connects its downstream end 51b to the process cartridge P via the vertically moving member 75.

[0076] The opening to which the downstream end 51b is connected corresponds to the receiving port of the developing container of the process cartridge P. The yellow receiving port will be called the first receiving port, the magenta receiving port the second receiving port, the cyan receiving port the third receiving port, and the black receiving port the fourth receiving port.

[0077] The operation when the connection of the downstream end 51b of the toner transport path 51 is released will be explained using Figure 7(b). The front door 72b is opened by rotating around the pivot shaft 72b2. The link member 73 rotates around the pivot shaft 73a while engaging with the elongated hole 72b1 of the front door 72b.

[0078] The sliding member 74 is held so as to be slidable in the first direction X by the engagement of a shaft 72c provided on the main body of the device with an elongated hole in the sliding member 74.

[0079] The slide member 74 moves along the first direction X as it is pulled along the direction X by the axis 73b of the link member 73. The slope formed in the hole 74a of the slide member 74 also moves along the direction X. The axis 75a of the vertical movement member 75 moves relative to the third direction, the Z direction, along the slope. This movement causes the vertical movement member 75 to move away from the process cartridge P, and the connection between the downstream end 51b of the toner transport path 51 and the process cartridge P is released, so that the tray 35 can be pulled out in the first direction X as shown in Figure 2.

[0080] (Cartridge structure) The structure of each toner cartridge 41 in this embodiment will be explained using Figure 5(a). The toner cartridge 41 has a first frame 41c, a second frame 41d, and a filter 42. The toner outlets 43b (first outlet, second outlet, third outlet, and fourth outlet) are provided in the first frame 41c.

[0081] The first frame 41c and the second frame 41d are injection-molded resin components. A sealing member (seal or shutter) not shown may be provided at the toner outlet 43b. When the toner cartridge 41 is not installed in the replenishment toner unit 40, the sealing member is configured to seal the toner outlet 43b, preventing the toner T contained inside from leaking out of the toner cartridge 41. When the toner cartridge 41 is installed in the replenishment toner unit 40, the sealing member is removed or moved, leaving the toner outlet 43b open.

[0082] The first frame 41c and the second frame 41d each have flange portions 41c1 and 41d2, respectively. The internal space SPY of the toner cartridge 41 shown in Figure 5(a) is formed by welding the flange portions 41c1 and 41d2 to each other by ultrasonic welding. The flange portions 41c1 and 41d2 may also be fixed to each other with adhesive or screws. The first frame is assembled to the second frame in this manner.

[0083] The filter 42 is provided to divide the internal space SPY of the toner cartridge 41 into two parts: the toner chamber 41a and the air chamber 41b. In other words, the air chamber 41b is adjacent to the toner chamber 41a via the filter 42.

[0084] The toner chamber 41a is configured to contain toner T. In the toner chamber 41a, the toner T is supported in the Z direction by the filter 42. The air chamber 41b does not contain toner. The filter 42 is made of a porous material, for example, made of resin fibers, and has a pore size and density that allows air to pass through but inhibits toner passage. In other words, the filter 42 is configured to allow air to pass through but inhibit toner passage.

[0085] As described above, the filter 42 is held by the first frame 41c and the second frame 41d, sandwiched between the flange portion 41c1 of the first frame 41c and the flange portion 41d2 of the second frame 41d. The filter 42 has an inclined portion that slopes downward towards the bottom 42a in the first direction X.

[0086] A toner path 43 is provided in the toner chamber 41a. In this embodiment, the toner path 43 is a tubular member injection-molded from resin. The toner path 43 may also be made of paper or rubber. The toner path 43 has a toner intake port 43a and a toner discharge port 43b. The toner path 43 is the path through which the toner T contained in the toner chamber 41a is transported toward the toner discharge port 43b. The toner path 43 has a first portion 43c that is provided with a toner intake port 43a which is an inlet and extends along a third direction Z, and a second portion 43d that is provided with a toner discharge port 43b which is an outlet and extends in a first direction X.

[0087] The direction in which the first portion 43c extends and the direction in which the second portion 43d extends are configured to intersect. The toner intake port 43a is positioned opposite the lowest part 42a, which is part of the filter 42, with a gap between them. Preferably, the toner intake port 43a is positioned close to the lowest part 42a.

[0088] When the amount of toner T in the toner chamber 41a becomes low, the toner T, which has been fluidized by the air received from the air supply port 44, moves along the slope of the filter 42 described above and is collected at the bottom 42a. The toner intake port 43a of the toner path 43 guides the toner T collected at the bottom 42a of the filter 42 to the discharge port 43b. In this way, the slope of the filter 42 collects the toner at the bottom of the filter 42, and the collected toner is transported to the discharge port 43b through the toner intake port 43a which is close to the bottom 42a.

[0089] In this way, even when the amount of toner stored in the toner chamber 41a of the toner cartridge 41 becomes low, the toner T at the bottom 42 can be efficiently discharged to the outside of the toner cartridge 41.

[0090] The cartridge in this embodiment has a structure that uses air to expel toner from the cartridge, eliminating the need for rotating members such as screws. Therefore, this allows the cartridge to have a simple structure with fewer parts.

[0091] (Toner transport mechanism) The mechanism by which toner contained in the toner chamber 41a of the toner cartridge 41 is transported to the developing unit P will be explained using Figure 5(a).

[0092] Air discharged from the discharge port 50a of the pump unit 50 is received into the air chamber 41b via the air supply port 44 of the toner cartridge 41. This air then increases the air pressure in the air chamber 41b, passes through the filter 42, and flows into the toner chamber 41a. The air that flows into the toner chamber 41a penetrates between the toner particles T, causing the toner T to become fluid. The toner T, now fluidized with the air, is transported by the air received into the air chamber 41a via the air supply port 44. The toner T is transported through the toner path 43 from the toner intake port 43a to the toner discharge port 43b and is discharged to the outside of the toner cartridge 41 from the toner discharge port 43b.

[0093] As in this embodiment, by providing an air chamber 41b, which is a highly sealed space, between the air supply port 44 and the filter 42, the air discharged from the air outlet 50a is efficiently directed to the filter 42 without being dispersed outside the toner cartridge 41. For example, suppose the toner cartridge 41 is subjected to vibration or left unattended for a long time, which can cause the toner T in the toner chamber 41a to aggregate. In such cases, the pressure required to allow air to flow into the toner cartridge 41 through the filter 42 becomes high. Even in such cases, by continuously supplying air from the pump unit 50 to the air chamber 41a and increasing the pressure (atmospheric pressure) inside the air chamber 41a, it becomes possible to supply air to the toner chamber 41a through the filter 42. Furthermore, in a configuration with an air chamber 41b, it is sufficient for the pump unit 50 to generate enough pressure to continuously supply air into the air chamber 41b until the pressure is sufficient for air to pass from the filter 42 into the toner chamber 41a. In addition, since no special performance is required for discharge speed or discharge volume, it is possible to use a small pump unit. This can ultimately contribute to the miniaturization of the image forming apparatus.

[0094] As shown in Figure 5(a), the toner T discharged from the toner outlet 43b of the toner cartridge 41 is transported to the downstream end 51b via the receiving port 51a of the toner transport path 51 and supplied to the developing container 3 of the process unit P.

[0095] As shown in Figure 3, air as well as toner T flows into the developing container 3 of the process unit P from the toner transport path 51, which can easily cause the internal pressure inside the developing container 3 to rise. Therefore, a filter is provided on the top surface of the developing container 3 of the process unit P. This filter is the exhaust filter section 25. The exhaust filter section 25 is a part in which through holes are provided in the frame portion that constitutes the developing container 3 of the process unit P, and a filter such as nonwoven fabric is provided in the through holes. Toner T flows into the inside of the developing container 3 of the process unit P along with air from the toner transport path 51. The exhaust filter 25 allows the passage of air but blocks the passage of toner T, and the toner T is discharged to the outside of the process unit P. This suppresses the rise in internal pressure inside the developing container 3 of the process unit P. If the internal pressure rises, it becomes difficult for toner T and air to flow into the developing container 3 from the toner cartridge 41 via the toner transport path 51, but this can be made less likely to occur.

[0096] (Removing and installing the toner cartridge) Figure 5 illustrates the operation of connecting the toner outlet 43b and the air supply port 44 when inserting or removing the toner cartridge 41.

[0097] Figure 5(a) shows the toner cartridge 41 installed in the toner supply unit 40. Figure 5(b) shows the toner cartridge 41 slightly pulled out from the toner supply unit 40. Figure 5(c) shows the toner cartridge 41 pulled out even further from the toner supply unit 40 than in the state shown in Figure 5(b).

[0098] As the toner cartridge 41 is pulled out in the first direction X, the air supply port 44 moves away from the discharge port 50a, as shown in Figure 5(b). Further pulling out then causes the toner discharge port 43b to move away from the toner receiving port 51a, as shown in Figure 5(c).

[0099] The toner inlet 51a is positioned to protrude from the discharge port 50a of the pump 50 by a distance L1 in the first direction X as shown in Figure 5(c). The toner outlet 43b of the toner cartridge 41 is positioned to protrude from the air supply port 44 by a distance L2 in the insertion direction in the first direction X as shown in Figure 5(c).

[0100] The system is configured such that when cartridge 41 is removed, the air supply path by the pump is released first, followed by the toner discharge path. Even if the internal pressure of toner cartridge 41 is high immediately after the toner transport operation, toner leakage is unlikely to occur. This is because the air supply path is released first, and the toner discharge path is released only after the internal pressure of toner cartridge 41 has sufficiently decreased.

[0101] <Second Embodiment> An image forming apparatus 1 according to a second embodiment of the present invention will be described with reference to Figures 8 and 9. Figure 8 is a perspective view showing the toner cartridge tray 146 of the image forming apparatus 1 in the extended state. Descriptions of parts of the image forming section that are the same as those in the first embodiment will be omitted.

[0102] A configuration different from the first embodiment will be explained using Figure 9, which shows a cross-sectional view of the replenishment toner unit 40.

[0103] The replenishment toner unit 40 is capable of mounting a toner cartridge 41 and has a toner cartridge tray 146 for holding the cartridge when mounted. As shown in Figure 8, the toner cartridge tray 146 has a handle portion 146a for pulling it out in a first direction X. The toner cartridge tray 146 is configured to slide relative to the replenishment toner unit 40 in the first direction X. The toner cartridge tray 146 has a first positioning portion 146b and a second positioning portion 146c for positioning the toner cartridge 41. The first engaged portion 41e and the second engaged portion 41f of the toner cartridge 41 are engaged with the first positioning portion 146b and the second positioning portion 146c, respectively.

[0104] When the toner cartridge tray 146 is pulled out from the replenishment toner unit 40 along a first direction X from an internal position to an external position, the cartridge 41 is positioned relative to the toner cartridge tray 146 and is pulled out together with the toner cartridge. After pulling out the toner cartridge tray 146, the user can replace the toner cartridge 41 by removing it from the toner cartridge tray 146 in a third direction Z.

[0105] The toner cartridge 41 can be replaced while it is placed on the toner cartridge tray 146, which has been pulled out to the external position of the replenishment toner unit 40. The user can pull out the toner cartridge 41 close to their hand for replacement. In addition, the toner cartridge 41 can be kept at a height that is easy to work with during the replacement process. Therefore, the workability when replacing the toner cartridge 41 is excellent.

[0106] Furthermore, the direction in which the toner cartridge tray 146 is pulled out is the same direction X as the direction in which the paper feed tray for the recording medium S is pulled out and the paper feed option tray is pulled out. The user can operate all of these from the front of the image forming apparatus, and can replace the toner cartridge 41, replenish the recording material S, and remove the recording material S from the output tray, resulting in excellent operability. [Explanation of symbols]

[0107] 1. Image forming apparatus 40 Toner Refill Unit 41 Toner Cartridges 42 filters 50 Air Pump 51 Toner transport path

Claims

1. An image forming apparatus, A first toner container for containing the first toner, A second toner container for containing a second toner, the second toner container being aligned with the first toner container in a first direction intersecting the direction of gravity, The device body is configured such that the first toner container and the second toner container can be attached to and detached from each other. Equipped with, The main body of the aforementioned device is A first developing unit comprising a rotatable first developing roller that carries a first toner, and a first developing container that houses the first toner carried on the first developing roller, the first developing unit being located above the first toner container and the second toner container, A second developing unit comprising a rotatable second developing roller for carrying a second toner, and a second developing container for containing the second toner supplied to the second developing roller, wherein the second developing unit is aligned with the first developing unit in a second direction intersecting the first direction and the direction of gravity, and is located above the first toner container and the second toner container, The first passage through which the first toner passes, The second passage through which the second toner passes, It has, The first toner is supplied from the first toner container to the first developer container via the first passage, and the second toner is supplied from the second toner container to the second developer container via the second passage. An image forming apparatus characterized by the following:

2. The first developing unit overlaps with at least a portion of the first toner container and at least a portion of the second toner container when viewed in the direction of gravity. The image forming apparatus according to feature 1.

3. The first toner container overlaps with at least a portion of the first developing unit and at least a portion of the second developing unit when viewed in the direction of gravity. The image forming apparatus according to feature 1.

4. The image forming apparatus according to claim 1, characterized in that the longitudinal direction of the first toner container and the longitudinal direction of the second toner container are the second direction.

5. The main body of the device has a pump for discharging air, The first toner is supplied from the first toner container to the first developer container via the first passage by air discharged by the pump. The second toner is supplied from the second toner container to the second developing container via the second passage by air discharged by the pump. The image forming apparatus according to feature 1.

6. The first toner container and the second toner container are mounted on the device body by being moved in a mounting direction along a second direction relative to the device body, and are detachable from the device body by being moved in a detachment direction opposite to the mounting direction relative to the device body. The image forming apparatus according to feature 1.

7. A first discharge port for discharging the first toner is provided at the downstream end of the first toner container in the mounting direction, and the first discharge port communicates with the upstream end of the first passage in the toner transport direction. A second discharge port for discharging the second toner is provided at the downstream end of the second toner container in the mounting direction, and the second discharge port communicates with the upstream end of the second passage in the toner transport direction. The image forming apparatus according to feature 6.

8. When the first end and the other end of the device body in the first direction are designated as the first end and the second end, A first receiving port is provided at the end of the first developing container on the first end side in the first direction, which is a first receiving port that communicates with the downstream end of the first passage in the toner transport direction. A second receiving port is provided at the end of the second developing container on the first end side in the first direction, which communicates with the downstream end of the second passage in the toner transport direction. The image forming apparatus according to feature 7.

9. The first passage has a first portion that extends upward, The second passage has a second portion that extends upward, The first and second portions are provided on the first end side in the first direction of the device body and on the downstream side in the mounting direction. The image forming apparatus according to feature 8.

10. The first passage and the second passage are each composed of a flexible tube that can be bent. The image forming apparatus according to feature 1.

11. The first passage and the second passage are each composed of a flexible tube that can be bent. The image forming apparatus according to feature 9.

12. The apparatus has a movable member that can move along the second direction between an internal position where the first and second developing units are inside the apparatus body and an external position where at least a portion of the first developing unit and at least a portion of the second developing unit are exposed outside the apparatus body, on which the first developing unit and the second developing unit can be mounted. The image forming apparatus according to feature 1.

13. The device is capable of mounting the first toner container and the second toner container, and has a movable member that can move along the second direction between an internal position where the first toner container and the second toner container are inside the device body and an external position where at least a portion of the first toner container and at least a portion of the second toner container are exposed outside the device body. The image forming apparatus according to feature 1.

14. The first toner container is, A first frame having an inlet for receiving air from the pump, A second frame which is assembled to the first frame and together with the first frame forms a space inside, A filter having a fixed outer perimeter and partitioning the space into an air chamber having the inlet and a toner storage chamber for storing toner, wherein the filter restricts the passage of toner between the air chamber and the toner storage chamber while allowing the passage of air, An outlet for discharging toner from the toner storage chamber to the outside along with air, The image forming apparatus according to feature 5.

Images