Developing device, process cartridge and image forming apparatus

Abstract

To provide a development device that realizes a configuration that can supply a developer from a developer storage chamber located below to a development chamber located above, and that can suppress backflow of a developer to a replenishment port provided in the developer storage chamber, a process cartridge, and an image forming device.SOLUTION: A developer storage chamber is provided with a replenishment port for replenishing a developer from the outside to the developer storage chamber; when viewed along a rotational axis direction of a rotational shaft part in a posture during use, when a rotation center of a rotational shaft part and a downstream side end part of a communication port in a rotational direction of a rotational shaft part are connected with a straight line, the communication port and the replenishment port are arranged on different sides of the straight line; and a restoration part is not provided on one side where the replenishment port is present, but is provided on the other side where the communication port is present.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus, a developing device and a process cartridge used in the image forming apparatus, and more particularly to an electrophotographic image forming apparatus that employs an electrophotographic system, and a developing device and a process cartridge used in the electrophotographic image forming apparatus. [Background technology]

[0002] Conventionally, detachable (replaceable) configurations such as a developing cartridge (including a developing means) and a process cartridge (including a developing means and a photosensitive drum) for the main body of an electrophotographic image forming apparatus have been widely known.

[0003] Among them, there is also a cartridge such as that described in Patent Document 1, which transports developer by flying it from a lower developer storage chamber to an upper developing chamber by using elastic deformation (elastic restoring force) of an agitating sheet.

[0004] On the other hand, in order to improve image formation efficiency, a technology is being considered in which a supply port is provided in the developer storage chamber of a cartridge as in Patent Document 1, and developer is directly supplied to the developer storage chamber from the outside through the supply port. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2011-253203 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the cartridge described in Patent Document 1, if a supply port is provided in the developer storage chamber, the rotation of the stirring sheet placed in the developer storage chamber may cause the developer in the developer storage chamber to flow back into the supply port when it is transported to the developing chamber located above.

[0007] The present invention aims to provide a developing device, a process cartridge, and an image forming apparatus that realize a configuration that enables developer to be supplied from a developer storage chamber located below to a developing chamber located above, and that can suppress backflow of developer into a supply port provided in the developer storage chamber. [Means for solving the problem]

[0008] The developing device of the present invention is a developing device that can be attached to the main body of an image forming device, and includes a developing frame, a developing chamber that accommodates a developer carrier that carries developer, a developer storage chamber that is located below the developing chamber in an orientation during use and that stores developer, and a communication port that communicates the developing chamber with the developer storage chamber; a receiving and conveying path having a receiving port for receiving developer from the outside of the developing device and a conveying path through which the developer is conveyed; a conveying member provided in the developer accommodating chamber and configured to convey the developer accommodated in the developer accommodating chamber to the developing chamber, the conveying member comprising a rotatable rotary shaft portion and an elastically deformable sheet portion having one end fixed to the rotary shaft portion and the other end being a free end; a developing device having the above-mentioned structure, wherein the developer storage chamber has a deformation portion, a restoration portion, and a supply port, and the deformation portion is a part of an inner wall of the developer accommodating chamber, the part abutting against the free end of the sheet part which rotates in accordance with the rotation of the rotary shaft part, thereby bending and elastically deforming the sheet part; The restoration unit is the developer storage chamber is a part of an inner wall of the developer storage chamber, and is provided in the developer storage chamber at a position upstream of the communication opening and downstream of the deformation portion in the rotation direction of the rotary shaft portion, and the deformation portion releases the deflection of the sheet portion in a state in which the sheet portion has been elastically deformed and restores it to its original state, thereby causing the developer carried on the sheet portion to fly toward the communication opening, The supply port is provided at the center in the longitudinal direction of the developer storage chamber, and communicates with the receiving and conveying path. The developer passing through the receiving and conveying path is supplied from the outside of the developer storage chamber to the developer storage chamber through the supply port. Resupply And, When viewed along the rotational axis of the rotating shaft portion in the posture attached to the device main body, when a straight line is drawn between the rotation center of the rotating shaft portion and the downstream end of the communication port in the rotational direction of the rotating shaft portion, the communication port and the supply port are located on different sides of the line, the restoration portion is not located on the side where the supply port is located, but on the other side where the communication port is located, and the supply port is located at a position closer to the rotation center in the direction of gravity than the lower end of the developer storage chamber.

[0009] The process cartridge of the present invention is characterized by comprising an image carrier that carries a developer image and the developing device, and being detachably mountable to an image forming apparatus.

[0010] The image forming apparatus of the present invention is characterized by comprising at least one of the developing device and the process cartridge, and a transfer member. [Effects of the Invention]

[0011] According to the present invention, a configuration is realized that allows developer to be supplied from a developer storage chamber located below to a developing chamber located above, and backflow of developer into a supply port provided in the developer storage chamber can be suppressed. [Brief explanation of the drawings]

[0012] [Figure 1] (a) is a cross-sectional conceptual diagram of a developing unit used in an image forming apparatus according to an embodiment of the present invention; (b) is an enlarged view of a main part of the developing unit; [Figure 2] 1 is a cross-sectional view of an image forming apparatus according to an embodiment of the present invention; [Figure 3] 1 is a cross-sectional view of a process cartridge used in an image forming apparatus according to an embodiment of the present invention; [Figure 4] FIG. 1 is a schematic perspective view of a process cartridge according to an embodiment of the present invention, viewed from above on the non-drive side; [Figure 5] (a) is a schematic perspective view of the process cartridge according to the embodiment of the present invention, seen from below on the drive side; (b) is a schematic perspective view of the process cartridge according to the embodiment of the present invention, seen from above on the drive side; [Figure 6] (a) A cross-sectional view of a toner cartridge (Y·M·C) used in an image forming apparatus according to an embodiment of the present invention, taken along the line A-A in FIG. 8; (b) A cross-sectional view of a toner cartridge (Y·M·C) taken along the line B-B in FIG. 8. [Figure 7](a) A cross-sectional view of a toner cartridge (K) used in an image forming apparatus according to an embodiment of the present invention, taken along the line A-A in FIG. 8; (b) A cross-sectional view of a toner cartridge (K) taken along the line B-B in FIG. 8. [Figure 8] (a) A perspective conceptual diagram of a toner cartridge (Y·M·C·K) according to an embodiment of the present invention, viewed from above on the drive side; (b) A perspective conceptual diagram of a toner cartridge (Y·M·C·K) with the side cover removed. [Figure 9] 1(a) to 1(d) are conceptual diagrams showing the toner transport state in the developing unit according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] The present invention can be embodied in the form of either an electrophotographic image forming apparatus (hereinafter sometimes simply referred to as "image forming apparatus"), or a process cartridge or developing device that constitutes a part of the image forming apparatus.

[0014] An image forming apparatus according to the present invention will now be described with reference to the drawings.

[0015] The examples described below are merely illustrative of the present invention, and the dimensions, materials, shapes, relative positional relationships, etc. of the components described below do not limit the scope of the present invention unless otherwise specified.

[0016] Here, an electrophotographic image forming apparatus is an apparatus that forms an image on a recording medium using an electrophotographic image forming method, and examples of the electrophotographic image forming apparatus include electrophotographic copying machines, electrophotographic printers (e.g., laser beam printers, LED printers, etc.), facsimile machines, word processors, etc.

[0017] The developing device used in the image forming apparatus has at least a developing means. The developing device is made into a cartridge that can be attached to and detached from the main body of the electrophotographic image forming apparatus. The developing device may also include a toner cartridge that can be attached to and detached from the frame of the developing device and that can replenish toner to the developing device.

[0018] Furthermore, a process cartridge constituting a part of an image forming apparatus is a cartridge in which a charging means, a developing means or a cleaning means and an electrophotographic photosensitive drum are integrated, and the cartridge is detachably mountable to the main body of an electrophotographic image forming apparatus. Also, a cartridge in which at least one of a charging means, a developing means or a cleaning means and an electrophotographic photosensitive drum are integrated, and the cartridge is detachably mountable to the main body of an electrophotographic image forming apparatus. Furthermore, a cartridge in which at least a developing means and an electrophotographic photosensitive drum are integrated, and the cartridge is detachably mountable to the main body of an electrophotographic image forming apparatus. It is also possible to use a process cartridge fixed to an image forming apparatus. [Example]

[0019] <Overall Configuration of Image Forming Apparatus 100> The overall configuration of the image forming apparatus 100 according to this embodiment will be described with reference to FIG.

[0020] FIG. 2 is a conceptual cross-sectional view of an image forming apparatus according to an embodiment of the present invention.

[0021] In this embodiment, the process cartridge 1 and the toner cartridge 13 are detachably mounted to the apparatus main body 100A of the image forming apparatus 100.

[0022] In this embodiment, the configurations and operations of the first to fourth image forming units are substantially the same except for the colors of the images they form. Therefore, in the following, unless a distinction is particularly required, the subscripts Y to K will be omitted and the description will be generalized.

[0023] The first to fourth process cartridges 1 are arranged in a row in the horizontal direction. Each process cartridge 1 is formed of a cleaning unit 4 and a developing unit 6 (developing device).

[0024] The cleaning unit 4 has a photosensitive drum 7 (image carrier), a charging roller 8 as charging means for uniformly charging the surface of the photosensitive drum 7, and a cleaning blade 10 as cleaning means.

[0025] The developing unit 6 includes a developing roller 11 (developer carrier) and a developing means for accommodating a developer T (hereinafter, toner) and developing an electrostatic latent image on the photosensitive drum 7.

[0026] The cleaning unit 4 and the developing unit 6 are supported so as to be able to swing relative to each other. The first to fourth process cartridges 1Y, 1M, 1C, and 1K accommodate yellow (Y), magenta (M), cyan (C), and black (K) toner in the developing unit 6, respectively.

[0027] The process cartridge 1 is detachably mountable to the image forming apparatus 100 via mounting means such as a mounting guide (not shown) and a positioning member (not shown) provided in the image forming apparatus 100.

[0028] A scanner unit 12 for forming an electrostatic latent image is disposed below the process cartridge 1. Furthermore, a waste toner transport unit 23 is disposed behind the process cartridge 1 (downstream in the mounting / removal direction of the process cartridge 1) in the image forming device.

[0029] The first to fourth toner cartridges 13 are arranged horizontally below the process cartridge 1 in an order corresponding to the color of the toner contained in each process cartridge 1.

[0030] That is, the first to fourth toner cartridges 13Y, 13M, 13C, and 13K contain yellow (Y), magenta (M), cyan (C), and black (K) toner, respectively. Each toner cartridge 13 supplies toner to the process cartridge 1 that contains toner of the same color.

[0031] The toner cartridge 13 is replenished when a remaining amount detection unit (not shown) provided in the apparatus main body 100A of the image forming apparatus 100 detects that the amount of toner remaining in the process cartridge 1 is insufficient. The toner cartridge 13 is detachably mountable to the image forming apparatus 100 via mounting means such as a mounting guide (not shown) and a positioning member (not shown) provided in the image forming apparatus 100. The process cartridge 1 and the toner cartridge 13 will be described in detail later.

[0032] Below the toner cartridges 13, first to fourth toner transport devices 14 are arranged corresponding to the respective toner cartridges 13. Each toner transport device 14 transports the toner received from each toner cartridge 13 upward and supplies the toner to each development unit 6.

[0033] An intermediate transfer unit 19 serving as an intermediate transfer member is provided above the process cartridge 1. The intermediate transfer unit 19 is disposed substantially horizontally with the primary transfer portion S1 side facing downward.

[0034] The intermediate transfer belt 18 facing each photosensitive drum 7 is a rotatable endless belt that is stretched around multiple stretching rollers. Primary transfer rollers 20 (transfer members) are arranged on the inner surface of the intermediate transfer belt 18 at positions that form primary transfer sections S1 with each photosensitive drum 7 via the intermediate transfer belt 18.

[0035] Furthermore, a secondary transfer roller 21, which is a secondary transfer member, contacts the intermediate transfer belt 18 and forms a secondary transfer section S2 with an opposing roller via the intermediate transfer belt 18. Furthermore, an intermediate transfer belt cleaning unit 22 is disposed on the opposite side of the secondary transfer section S2 in the left-right direction (the direction in which the secondary transfer section S2 and the intermediate transfer belt are stretched).

[0036] A fixing unit 25 is disposed above the intermediate transfer unit 19. The fixing unit is composed of a heating unit 26 and a pressure roller 27 that is in pressure contact with the heating unit. A discharge tray 32 is disposed on the top surface of the apparatus main body 100A, and a waste toner collection container 24 is disposed between the discharge tray 32 and the intermediate transfer unit. A paper feed tray 2 for storing recording material 3 is disposed at the bottom of the apparatus main body.

[0037] <Image formation process> Next, the image forming operation in the image forming apparatus 100 will be described with reference to FIGS.

[0038] FIG. 3 is a conceptual cross-sectional view of a process cartridge used in the image forming apparatus according to the embodiment of the present invention.

[0039] During image formation, the photosensitive drum 7 is rotated at a predetermined speed in the direction of arrow A in Figure 3. The intermediate transfer belt 18 is rotated in the direction of arrow B (the same direction as the rotation of the photosensitive drum 7).

[0040] First, the surface of the photosensitive drum 7 is uniformly charged by the charging roller 8. Next, the surface of the photosensitive drum 7 is scanned and exposed to laser light emitted from the scanner unit 12, thereby forming an electrostatic latent image on the photosensitive drum 7 based on image information.

[0041] The electrostatic latent image formed on the photosensitive drum 7 is developed into a toner image by the developing unit 6. At this time, the developing unit 6 is pressurized by a developing pressure unit (not shown) provided in the apparatus main body 100A. Then, the toner image formed on the photosensitive drum 7 is primarily transferred onto the intermediate transfer belt 18 by the primary transfer roller 20.

[0042] For example, when a full-color image is formed, the above-described process is sequentially performed in the image forming units S1Y to S1K, which are the first to fourth primary transfer units, so that toner images of each color are sequentially superimposed on the intermediate transfer belt 18.

[0043] Meanwhile, the recording material 3 stored in the paper feed tray 2 is fed at a predetermined control timing and transported to the secondary transfer section S2 in synchronization with the movement of the intermediate transfer belt 18. Then, the four-color toner image on the intermediate transfer belt 18 is secondarily transferred onto the recording material 3 all at once by a secondary transfer roller 21 that is in contact with the intermediate transfer belt 18 via the recording material 3.

[0044] Thereafter, the recording material 3 onto which the toner image has been transferred is conveyed to the fixing unit 25. In the fixing unit 25, the recording material 3 is heated and pressurized, so that the toner image is fixed onto the recording material 3. Thereafter, the fixed recording material 3 is conveyed to the discharge tray 32, and the image forming operation is completed.

[0045] Furthermore, primary transfer residual toner (waste toner) remaining on the photosensitive drum 7 after the primary transfer process is removed by a cleaning blade 10. Secondary transfer residual toner (waste toner) remaining on the intermediate transfer belt 18 after the secondary transfer process is removed by an intermediate transfer belt cleaning unit 22.

[0046] The waste toner removed by the cleaning blade 10 and the intermediate transfer belt cleaning unit 22 is transported by a waste toner transport unit 23 provided in the apparatus main body 100A and accumulated in a waste toner collection container 24. Note that the image forming apparatus 100 is also capable of forming a monochromatic or multicolor image using only a desired single or several (but not all) image forming units.

[0047] <Process cartridge> Next, the overall structure of the process cartridge 1 to be mounted in the image forming apparatus 100 according to this embodiment will be described with reference to FIGS.

[0048] 1(a) is a cross-sectional conceptual view of a developer unit used in an image forming apparatus according to an embodiment of the present invention, and FIG. 1(b) is an enlarged view of a main part of the developer unit.

[0049] 4 is a conceptual perspective view of the process cartridge 1 according to the embodiment of the present invention, viewed from above on the non-drive side, showing the state of the process cartridge 1 as viewed from the front (upstream side in the process cartridge mounting / removal direction).

[0050] Fig. 5(a) is a conceptual perspective view of the process cartridge according to an embodiment of the present invention, viewed from below on the drive side. Fig. 5(b) is a conceptual perspective view of the process cartridge, viewed from above on the drive side. That is, Fig. 5(a) shows the state of the process cartridge 1 as viewed from the rear (downstream side in the process cartridge mounting / removal direction).

[0051] The process cartridge 1 is made up of a cleaning unit 4 and a developing unit 6. The cleaning unit 4 and the developing unit 6 are coupled to each other so as to be able to swing about a rotation support pin 30.

[0052] The cleaning unit 4 has a cleaning frame 5 that supports various members inside the cleaning unit 4. In addition to the photosensitive drum 7, charging roller 8, and cleaning blade 10, the cleaning unit 4 also has a waste toner screw 15 that extends in a direction parallel to the rotation axis of the photosensitive drum 7.

[0053] The cleaning frame 5 rotatably supports the photosensitive drum 7, and cleaning bearings 33 equipped with cleaning gear trains 31 for transmitting drive from the photosensitive drum to the waste toner screw 15 are arranged at both longitudinal ends of the cleaning unit 4.

[0054] The charging roller provided in the cleaning unit 4 is biased in the direction of arrow C toward the photosensitive drum 7 by charging roller pressure springs 36 arranged on both ends. The charging roller is provided to follow the rotation of the photosensitive drum, and when the photosensitive drum 7 is rotationally driven in the direction of arrow A during image formation, the charging roller rotates in the direction of arrow D (the forward direction of the rotation of the photosensitive drum 7).

[0055] The cleaning blade 10 provided in the cleaning unit 4 is composed of an elastic member 10a for removing residual toner (waste toner) remaining on the surface of the photosensitive drum 7 after the primary transfer, and a support member 10b for supporting the elastic member 10a. The waste toner removed from the surface of the photosensitive drum 7 by the cleaning blade 10 is stored in a waste toner storage chamber 9 formed by the cleaning blade 10 and the cleaning frame 5.

[0056] The waste toner contained in the waste toner storage chamber 9 is transported toward the rear of the image forming apparatus 100 (downstream in the attachment / detachment direction of the process cartridge 1) by a waste toner transport screw 15 installed in the waste toner storage chamber 9. The transported waste toner is discharged from a waste toner discharge section 35 and delivered to a waste toner transport unit 23 of the image forming apparatus 100.

[0057] The developing unit 6 has a developing frame 16 that supports various members within the developing unit 6. The developing frame 16 is divided into a developing chamber 16a in which the developing roller 11 and a supply roller 17 (supply member) are provided, and a toner storage chamber 16b (developer storage chamber) in which toner is stored and a stirring member 29 (conveying member) is provided.

[0058] The developing chamber 16a is provided with a developing roller 11, a supply roller 17, and a developing blade 28. The developing roller 11 carries toner, and during image formation, rotates in the direction of arrow E and conveys the toner to the photosensitive drum 7 by coming into contact with the photosensitive drum 7.

[0059] The developing roller 11 is rotatably supported by the developing frame 16 at both ends in its longitudinal direction (direction of rotation axis) by developing bearing units 34. The supply roller 17 is rotatably supported by the developing frame 16 by the developing bearing units 34 while in contact with the developing roller 11, and rotates in the direction of arrow F during image formation. Furthermore, a developing blade 28 serving as a layer thickness regulating member for regulating the thickness of the toner layer formed on the developing roller 11 is disposed so as to abut against the surface of the developing roller 11.

[0060] The toner storage chamber 16b is provided with an agitating member 29 for agitating the stored toner T and transporting the toner to the supply roller 17 via the development chamber communication port 16c (communication port). The agitating member 29 has a rotation shaft 29a (rotation shaft portion) parallel to the rotation axis direction of the development roller 11, and an agitating sheet 29b, which is a flexible sheet and serves as a transport member. One end (29b1) of the agitating sheet 29b is attached to the rotation shaft 29a, and the other end (29b2) of the agitating sheet 29b is a free end. The rotation shaft 29a rotates, causing the agitating sheet 29b to rotate in the direction of arrow G (rotation direction), thereby agitating the toner.

[0061] The developing unit 6 has a developing chamber communication port 16c that communicates between the developing chamber 16a and the toner storage chamber 16b. In this embodiment, when the developing unit 6 is in a normal use position (position during use), the developing chamber 16a is located above the toner storage chamber 16b. The toner in the toner storage chamber 16b that is pumped up by the agitating member 29 is supplied to the developing chamber 16a through the developing chamber communication port 16c.

[0062] Furthermore, the developing unit 6 is provided with a toner receiving port 40 at one end downstream in the attachment / detachment direction. A toner receiving port seal member 45 and a toner receiving port shutter 41 that is movable in the front-to-rear direction are disposed above the toner receiving port 40. The toner receiving port 40 is closed by the receiving port shutter 41 when the process cartridge 1 is not attached to the image forming apparatus 100. The receiving port shutter 41 is configured to open when urged by the image forming apparatus 100 in conjunction with the attachment / detachment operation of the process cartridge 1.

[0063] A receiving and conveying path 42 is provided in communication with the toner receiving port 40, and a receiving and conveying screw 43 is disposed inside the path. Furthermore, a storage chamber communication port 44 (supply port) for supplying toner to the toner storage chamber 16b is provided near the longitudinal center of the developing unit 6, and the receiving and conveying path 42 communicates with the toner storage chamber 16b. The receiving and conveying screw 43 extends parallel to the rotational axes of the developing roller 11 and the supply roller 17, and conveys the toner received through the toner receiving port 40 to the toner storage chamber 16b via the storage chamber communication port 44.

[0064] Thus, in this embodiment, the developing unit includes the developing frame (16) and the transport member 29.

[0065] The developing frame (16) includes a developing chamber (16a) that houses a developer carrier (11) that carries developer, a developer storage chamber (16b) that is located below the developing chamber when in an in-use position and stores developer, and a communication port (16c) that connects the developing chamber and the developer storage chamber.

[0066] The transport member 29 is provided in the developer storage chamber and transports the developer stored in the developer storage chamber to the developing chamber. The transport member includes a rotatable shaft portion (29a) and an elastically deformable sheet portion (29b) having one end (29b1) fixed to the shaft portion and the other end (29b2) being a free end.

[0067] The developer storage chamber is provided with a deformation portion (67), which abuts against the free end of the sheet portion that rotates in conjunction with the rotation of the rotating shaft portion, thereby causing the sheet portion to bend and elastically deform.

[0068] The developer storage chamber is also provided with a restoring portion (68). The restoring portion (68) is provided in the developer storage chamber at a position upstream of the communication opening and downstream of the deformation portion in the rotation direction (G) of the rotating shaft. The restoring portion releases and restores the sheet portion that has been elastically deformed by the deformation portion, thereby causing the developer carried on the sheet portion to fly toward the communication opening.

[0069] The developer storage chamber is also provided with a supply port (44) for supplying developer from the outside to the developer storage chamber.

[0070] When viewed along the rotation axis (X1) of the rotating shaft in the posture during use, the rotation center (X0) of the rotating shaft and the downstream end (16c1) of the communication port in the rotation direction of the rotating shaft are connected by an imaginary straight line (H). In this case, the communication port and the supply port are located on different sides (H1, H2) of the straight line.

[0071] The restoring portion is not provided on the one side (H2) where the supply port is present, but on the other side (H1) where the communication port is present.

[0072] <Toner cartridge> Next, the overall configuration of the toner cartridge 13 to be mounted in the image forming apparatus 100 according to this embodiment will be described with reference to FIG.

[0073] Fig. 6(a) is a conceptual cross-sectional view of a toner cartridge (Y·M·C) used in an image forming apparatus according to an embodiment of the present invention, taken along the line A-A in Fig. 8 (described later). Fig. 6(b) is a conceptual cross-sectional view of the toner cartridge (Y·M·C) taken along the line B-B in Fig. 8.

[0074] 6(a) shows a cross section of the toner cartridge (13Y, 13M, 13C) at the center in the longitudinal direction (front-rear direction), and FIG. 6(b) shows a cross section of the toner cartridge (13Y, 13M, 13C) at the supply opening 52 on the rear side in the longitudinal direction (front-rear direction).

[0075] Fig. 7(a) is a conceptual cross-sectional view of a toner cartridge (K) used in an image forming apparatus according to an embodiment of the present invention, taken along the line A-A in Fig. 8 (described later). Fig. 7(b) is a conceptual cross-sectional view of the toner cartridge (K) taken along the line B-B in Fig. 8.

[0076] 7(a) shows a cross section of the toner cartridge (13K) at the center in the longitudinal direction (front-to-back direction), and FIG. 7(b) shows a cross section of the toner cartridge (13K) at the supply opening 52 on the rear side in the longitudinal direction (front-to-back direction).

[0077] Fig. 8(a) is a schematic perspective view of the toner cartridge (Y·M·C·K) according to an embodiment of the present invention, viewed from above the drive side. Fig. 8(b) is a schematic perspective view of the toner cartridge (Y·M·C·K) with the side cover removed.

[0078] That is, Figure 8(a) shows the toner cartridges (13Y, 13M, 13C) as viewed from the rear, and Figure 8(b) shows the toner cartridges (13Y, 13M, 13C) as viewed from the rear with the side cover 62 removed.

[0079] The toner cartridge 13 includes a supply frame 50 that supports various components inside the toner cartridge 13, and a supply toner storage chamber 51 that stores toner inside. In addition, when the toner cartridge 13 is in a normal use position (position during use), a supply frame opening 52 is provided on the bottom side.

[0080] A supply toner stirring member 53, a supply toner transport screw 54, and a partition member 55 are provided in the supply toner storage chamber 51. In this embodiment, the black (K) toner cartridge (13K) is larger in the width direction (left-right direction) than the color (Y, M, C) toner cartridges (13Y, 13M, 13C).

[0081] The supply agitation member 53 is disposed parallel to the longitudinal direction of the toner cartridge 13 and is rotatably supported by the supply frame 50. The supply agitation member 53 also has a rotating shaft 53a and a supply agitation sheet 53b, which is a flexible sheet and serves as a conveying member. One end of the supply agitation sheet 53b is attached to the rotating shaft 53a, and the other end of the supply agitation sheet 53b is a free end. When the rotating shaft 53a rotates, the supply agitation sheet 53b rotates in the direction of arrow G, causing the toner to be agitated by the supply agitation sheet 53b and sent to the supply conveying screw 54.

[0082] The supply toner transport screw 54 is disposed parallel to the rotation axis of the supply toner agitator and is rotatably supported by the supply frame 50. As the supply toner transport screw 54 rotates, it transports the toner in the supply toner storage chamber from front to rear (from upstream to downstream in the toner cartridge installation / removal direction). That is, it transports the toner toward the toner supply opening 52.

[0083] The partition member 55 forms a tunnel portion 56 together with the supply frame 50. The tunnel portion 56 is formed to correspond to the outer diameter of the supply toner transport screw 54, and serves to scrape and transport a fixed amount of toner transported by the supply toner transport screw 54. Similarly, the partition member 55 forms a toner discharge chamber 57 together with the supply frame 50.

[0084] Toner discharge chamber 57 is provided with supply frame opening 52. Pump 58, which has an expandable bellows portion 58a, is provided in communication with the interior. Pump 58 expands and contracts using a drive train (described later), allowing its internal volume to vary. As pump 58 expands and contracts, the internal pressure of supply toner storage chamber 51 and toner discharge chamber 57 fluctuates, and air is suctioned and exhausted through supply frame opening 52, allowing toner to be stably discharged.

[0085] A drive train is disposed on the rear side of the toner cartridge 13. A drive input gear 59 receives a rotational drive from the apparatus main body 100A and transmits the rotation to a cam gear 60. A cam groove 60a is provided in the cam gear 60, and a link protrusion 61a of a link mechanism 61 engages with the cam groove 60a.

[0086] The link mechanism 61 is supported by the side cover 62 so as to be movable in the front-rear direction. When the cam gear 60 rotates, the cam protrusion 61a passes alternately through the peaks and valleys of the cam groove 60a, causing the link mechanism 61 to reciprocate in the front-rear direction.

[0087] Link mechanism 61 is connected to coupling portion 58b of pump 58, and coupling portion 58b of pump 58 reciprocates in conjunction with link mechanism 61. When bellows portion 58a of pump 58 expands and contracts, the internal volume of pump 58 fluctuates, and as a result, the internal pressures of replenishment toner storage chamber 51 and toner discharge chamber 57 fluctuate.

[0088] Next, a screw gear 64 is provided at the end of the aforementioned supply toner transport screw 54 , and the screw gear 64 receives rotational drive from the cam gear 60 to rotate the supply toner transport screw 54 .

[0089] In addition, in the toner discharge chamber 57, in the normal position (position during use), a supply frame body opening 52 and a supply port shutter 41, which has a supply port 63 on the lower surface, are supported by the supply frame body 50 so as to be movable in the front-rear direction. When the toner cartridge 13 is not attached to the image forming apparatus 100, the supply frame body opening 52 is closed by the supply port shutter 41.

[0090] The supply port shutter 41 is configured to move to a predetermined position by being urged by the image forming apparatus 100 in conjunction with the installation and removal of the toner cartridge 13. When the supply port shutter 41 is attached to the image forming apparatus 100, the supply frame opening 52 and the supply port 63 communicate with each other, allowing toner to be discharged from the toner cartridge 13.

[0091] <Toner transport configuration> Next, the toner transport configuration in the developing unit 6 will be described in detail with reference to FIG.

[0092] Fig. 1(a) shows the toner transport state, and Fig. 1(b) shows the configuration in the vicinity of the developer chamber communication port.

[0093] In this embodiment, unless otherwise specified, terms indicating directions such as up, down, vertical, and horizontal in the configuration of the developing unit 6 indicate the directions when viewed in a normal state of use. In other words, the normal state of use of the developing unit 6 is a state in which the developing unit 6 is properly attached to the apparatus main body 100A of the image forming apparatus that is properly arranged, and is available for image formation operations.

[0094] 1(a), the developing unit 6 has a developing chamber 16a and a toner storage chamber 16b. The developing chamber 16a contains the developing roller 11, the supply roller 17, the developing blade 28, etc. The toner storage chamber 16b contains the toner to be supplied to the developing chamber 16a, and is provided with an agitating member 29 (conveying member) that supplies the toner to the developing chamber 16a.

[0095] The toner storage chamber 16b is disposed vertically lower than the developing chamber 16a, so that the toner is transported from the toner storage chamber 16b to the developing chamber 16a against the force of gravity.

[0096] As described above, when the agitator 29 transports the toner from the toner storage chamber 16b to the developing chamber 16a against gravity, the toner is transported to the supply port (the storage chamber communication port 44) through which the toner is replenished from the toner cartridge. This can cause toner clogging at the storage chamber communication port 44, which can easily lead to poor toner supply from the receiving / transporting screw 43 to the toner storage chamber 16b.

[0097] Therefore, the object of this embodiment is to prevent the toner transported from the toner storage chamber 16b to the developing chamber 16a from flowing back into the storage chamber communication port 44 when the toner is transported against gravity.

[0098] The developing unit 6 has a developing chamber 16a and a toner storage chamber 16b formed in a developing frame 16. The developing chamber 16a is provided with a developing roller 11 and a supply roller 17. The toner storage chamber 16b is disposed below the developing chamber 16a. The toner storage chamber 16b stores toner to be supplied to the developing chamber 16a.

[0099] Between the developing chamber 16a and the toner storage chamber 16b, a partition wall 66 (partition portion) having a developing chamber communication port 16c through which toner passes is provided. The developing chamber communication port 16c is provided above the toner storage chamber 16b. A resilient stirring member 29 is rotatably provided in the toner storage chamber 16b to supply toner to the developing chamber 16a.

[0100] The toner-accommodating chamber 16b is provided with a deformation portion 67 below the developing chamber communication port 16c, which comes into contact with the agitation sheet 29b. As the agitation sheet 29b rotates, it comes into contact with the deformation portion 67. This causes the agitation sheet 29b to receive force from the deformation portion 67. As a result, the agitation sheet 29b deforms against its own elastic force.

[0101] Furthermore, the agitation sheet 29b rotates while in contact with the deformation portion 67, and thereby carries and transports the toner on the surface downstream of the rotation direction of the agitation sheet 29b. In this embodiment, the deformation portion 67 refers to the portion of the inner wall of the toner storage chamber 16b from below the developing chamber communication port 16c to the point P where the agitation sheet 29b separates (only a portion is shown in FIG. 1(a)).

[0102] Furthermore, a restoring portion 68 is provided in the toner storage chamber 16b downstream of the deforming portion 67 in the rotation direction of the agitating member 29 and upstream of the developing chamber communication port 16c. Here, the restoring portion 68 is a portion for releasing the contact between the agitating sheet 29b and the inner wall of the toner storage chamber 16b. In this embodiment, the restoring portion 68 refers to the portion of the inner wall of the toner storage chamber 16b from the position of point P to the developing chamber communication port 16c. Furthermore, the restoring portion 68 is disposed above a horizontal plane including the rotation axis of the agitating member 29.

[0103] Therefore, as the agitating member 29 rotates in the direction of arrow G, the leading end of the free end side (the inner wall side of the toner storage chamber 16b) of the agitating sheet 29b passes through the deformation portion 67, and then the agitating sheet 29b is released from contact with the inner wall of the toner storage chamber 16b. Then, the agitating sheet 29b is released from the state deformed by the deformation portion 67, and returns to its natural state (original shape) due to the elastic restoring force of the agitating sheet 29b.

[0104] Due to the change in shape of the agitation sheet 29b in the restoration direction (the direction of arrow J), the toner carried and transported on the agitation sheet 29b is transported against gravity toward the developing chamber communication port 16c. The developing chamber communication port 16c is located downstream of the restoration portion 68 in the rotation direction of the agitation member 29.

[0105] <Positional relationship of the containment room communication opening> Next, the positional relationship of the storage chamber communication opening 44 in the developing unit 6 will be described in detail with reference to FIGS.

[0106] 9(a) to 9(d) are conceptual diagrams showing the state of toner transport within the development unit of the embodiment of the present invention. In the configuration of this embodiment, toner is transported in the order of FIG. 9(a) to 9(d).

[0107] 1(a), when viewed along the rotational axis direction X1, a (virtual) straight line H can be seen to connect the rotation center X0 of the agitating member 29 and the downstream end 16c1 (downstream end) of the developing chamber communication port 16c in the rotational direction G of the agitating member 29. When the straight line H is used as a reference, in this embodiment, the restoring portion 68 is provided on the other side (H1) where the developing chamber communication port 16c is present.

[0108] 9(a), the density of toner T1 is in a "sparse state" before agitation member 29 rotates and toner T1 is conveyed by agitation sheet 29b. On the other hand, as shown in FIG. 9(b), when agitation member 29 rotates, toner T2 is sandwiched between the wall surface of toner storage chamber 16b and agitation sheet 29b, and the toner (its density) becomes "dense."

[0109] A case will be considered where the containing chamber communication port 44 is provided below the point P position on the other side (H1) where the developing chamber communication port 16c exists when the straight line H is used as the reference.

[0110] In this case, as shown in Fig. 9(b), when the agitator 29 rotates, the dense toner T2 conveyed to the agitator sheet 29b exerts a higher pressure on the wall surface of the toner storage chamber 16b than the sparse toner T1 as shown in Fig. 9(a). As a result, the toner may flow back from the toner storage chamber 16b through the storage chamber communication port 44 to the receiving and conveying path 42 for the replenishment toner, causing a blockage and resulting in a failure to supply toner from the toner cartridge.

[0111] Also, a case will be considered where the containing chamber communication port 44 is provided above the point P position on the other side (H1) where the developing chamber communication port 16c exists when the straight line H is used as the reference.

[0112] 9(d), there is a possibility that the toner transported against gravity toward the developing chamber communication port 16c (in the direction of arrow I) may flow back from the toner storage chamber 16b through the storage chamber communication port 44 into the receiving and transporting path 42 for replenishment of toner. This may cause toner clogging and lead to poor toner supply from the toner cartridge.

[0113] Therefore, in this embodiment, when the straight line H is used as a reference, the storage chamber communication port 44 is provided on one side (H2) where the developing chamber communication port 16c does not exist and below the partition wall 66. As a result, after the agitation member 29 rotates and the agitation sheet 29b passes through the deformation portion 67, the toner carried and transported on the opened agitation sheet 29b is transported against gravity toward the developing chamber communication port 16c. Therefore, it is possible to suppress toner transport (backflow) toward the storage chamber communication port 44, which is provided on one side (H2) when the straight line H is used as a reference.

[0114] The configuration of the present invention can be summarized as follows.

[0115] (1) The developing device (6) of the present invention is a developing frame (16) including a developing chamber (16a) that accommodates a developer carrier (11) that carries developer, a developer storage chamber (16b) that is located below the developing chamber in an orientation during use and that stores developer, and a communication port (16c) that communicates the developing chamber with the developer storage chamber; and a transport member (29) provided in the developer storage chamber (16b) for transporting the developer stored in the developer storage chamber to the developing chamber.

[0116] The conveying member 29 includes a rotatable shaft portion (29a) and an elastically deformable sheet portion (29b) having one end (29b1) fixed to the shaft portion and the other end (29b2) being a free end.

[0117] The developing device (6) a deformation portion (67) provided in the developer storage chamber (16b) and configured to come into contact with a free end (29b2) of the seat portion (29b) that rotates in accordance with the rotation of the rotation shaft portion (29a), thereby bending and elastically deforming the seat portion; The developer storage chamber (16b) further includes a restoring portion (68) provided in the developer storage chamber (16b) at a position upstream of the communication opening (16c) and downstream of the deforming portion (67) in the rotation direction (G) of the rotating shaft portion (29a).

[0118] The restoring portion (68) is configured to release and restore the sheet portion (29b) that has been elastically deformed by the deforming portion (67), thereby causing the developer carried on the sheet portion (29b) to fly toward the communication opening (16c).

[0119] The developer storage chamber (16b) is provided with a supply port (44) for supplying developer from the outside to the developer storage chamber. When viewed along the rotation axis direction (X1) of the rotating shaft portion (29a) in the attitude during use, when a straight line (H) connects the rotation center (X0) of the rotating shaft portion and the downstream end portion (16c1) of the communication port (16c) in the rotation direction (G) of the rotating shaft portion, The communication port (16c) and the supply port (44) are arranged on different sides (H1, H2) of a straight line (H), The restoring portion (68) is not provided on the one side (H2) where the supply port (44) is present, but is provided on the other side (H1) where the communication port (16c) is present.

[0120] (2) In the developing device of the present invention, In the usage position, at least a portion of the supply port (44) may be located below the center of rotation (X0) of the rotation shaft portion (29a).

[0121] (3) In the developing device of the present invention, In the posture during use, the highest position (P11) of the supply port (44) may be located lower than the lowest position (P21) of the restoring portion (68). In the present invention, the lowest position of the restoring portion (68) is the position at which the free end (29b2) of the seat portion (29b) starts to change from a state of contact with the inner wall surface of the developing frame that constitutes the restoring portion (68) to a state of separation during rotation.

[0122] (4) In the developing device of the present invention, In the posture during use, the highest position (P11) of the supply port (44) may be located lower than the highest position (P31) of the deformation portion (67). The highest position of the deformation portion (67) is the position on the inner wall surface of the developing frame that constitutes the deformation portion (67) that is the shortest distance from the rotation center X0 of the rotation shaft portion (29a).

[0123] (5) In the developing device of the present invention, In the attitude during use, the highest position (P11) of the supply port (44) may be positioned above the developer surface (LV) of the developer contained in the developer containing chamber (16b) when the developer is not in use.

[0124] (6) In the developing device of the present invention, The developing frame (16) may include a partition (66) that separates the developing chamber (16a) from the developer storage chamber (16b), and the partition (66) may include a first partition (66A) and a second partition (66B) located upstream of the first partition.

[0125] In addition, in the posture during use, the second partition portion (66B) may be set to have a larger inclination angle (66B1) with respect to the horizontal direction (W) than the first partition portion (66A) (66B1>66A1), and the communication opening (16c) may be provided in the second partition portion (66B).

[0126] (7) In the developing device of the present invention, When viewed along the rotation axis direction (X1) of the rotating shaft portion (29a) in the posture during use, a perpendicular line (G1) passing through the position of the lowermost end (66B2) of the second partition portion (66B) can be used as a reference.

[0127] In this case, the supply port (44) may be located on a side (G12) of the perpendicular line that is different from the side (G11) on which the communication port (16c) is located.

[0128] (8) In the developing device of the present invention, The developing chamber (16a) may be provided with a supply member (17) that comes into contact with the developer carrier (11) and supplies the developer to the developer carrier.

[0129] (9) In the developing device of the present invention, The developer may be a one-component non-magnetic developer.

[0130] (10) In the developing device of the present invention, The developing device (6) may be detachable from the image forming device (100) that forms the image.

[0131] (11) The process cartridge (1) of the present invention is an image carrier (7) that carries a developer image; The developing device (6) is detachably attached to the image forming apparatus (100).

[0132] (12) In the process cartridge of the present invention, After the developer image is transferred from the image carrier (7), the developer remaining on the image carrier may be collected by the developer carrier (11).

[0133] (13) The image forming apparatus of the present invention comprises: At least one of the developing device (6) or the process cartridge (1); and a transfer member (20). [Explanation of symbols]

[0134] 6. Development unit (developing device) 11 Developing roller (developer carrier) 16 Developing frame 16a Developing Room 16b Toner storage chamber (developer storage chamber) 16c Developing chamber communication port (communication port) 16c1 Downstream end 29 Stirring member (conveying member) 29a Rotating shaft (rotating shaft part) 29b Stirring sheet (sheet part) 29b1 One end (fixed end) 29b2 Other end (free end) 44 Containment Room Communication Port (Supply Port) 67 Deformed part 68 Restoration Department G Rotation direction H (imaginary) line H1 Other side (side with communication port) H2 One side (the side where the supply port is located) X0 rotation center X1 Rotation axis direction

Claims

1. A developing device configured to be mountable to a main body of an image forming apparatus, A developing frame, a developing chamber containing a developer carrier that carries a developer; a developer storage chamber located below the developing chamber in an in-use position and configured to store a developer; a communication port that communicates the developing chamber with the developer storage chamber; a receiving and conveying path having a receiving port for receiving developer from the outside of the developing device and a conveying path through which the developer is conveyed; a developing frame body including the developing device; a transport member provided in the developer storage chamber and configured to transport the developer stored in the developer storage chamber to the developing chamber, a rotatable rotation shaft portion; a sheet portion having one end fixed to the rotary shaft portion and the other end being a free end and capable of elastic deformation; a conveying member comprising: A developing device having the developer storage chamber has a deforming portion, a restoring portion, and a supply port, the deformation portion is a part of an inner wall of the developer accommodating chamber, and abuts against the free end of the sheet portion that rotates in accordance with the rotation of the rotary shaft portion, thereby bending and elastically deforming the sheet portion; the restoring portion is a part of an inner wall of the developer accommodating chamber, and is provided in the developer accommodating chamber at a position upstream of the communication opening and downstream of the deformation portion in the rotation direction of the rotary shaft portion, and the deformation portion releases the deflection of the sheet portion in a state in which the sheet portion has been elastically deformed, thereby causing the developer carried on the sheet portion to fly toward the communication opening, the supply port is provided at a center portion in a longitudinal direction of the developer storage chamber and communicates with the receiving and conveying path; the developer passing through the receiving and conveying path is replenished from the outside of the developer accommodating chamber to the developer accommodating chamber through the replenishment port, When viewed along the rotation axis direction of the rotating shaft portion in a posture where the rotating shaft portion is attached to the device body, when a straight line is drawn between a rotation center of the rotary shaft portion and a downstream end of the communication port in the rotation direction of the rotary shaft portion, the communication port and the supply port are arranged on different sides of the straight line, The restoring portion is provided on the other side where the communication port is present. A developing device characterized by:

2. 2. The developing device according to claim 1, wherein, in an orientation during use, at least a portion of said supply port is positioned below the center of rotation of said rotary shaft portion.

3. 3. The developing device according to claim 1, wherein, in an orientation during use, the highest position of said supply port is located below the lowest position of said restoring portion.

4. 4. The developing device according to claim 1, wherein, in an orientation during use, the highest position of the supply port is located below the highest position of the deformation portion.

5. The developing device according to any one of claims 1 to 4, characterized in that, in a posture during use, the highest position of the supply port is located above the surface of the developer contained in the developer storage chamber when the device is unused.

6. the developing frame includes a partition portion that separates the developing chamber from the developer storage chamber, The partition section includes a first partition section and a second partition section located upstream of the first partition section, Equipped with In a posture during use, the second partition portion has a larger inclination angle with respect to the horizontal direction than the first partition portion, 6. The developing device according to claim 1, wherein the communication opening is provided in the second partition portion.

7. 7. The developing device according to claim 6, wherein, when viewed along the rotational axis of the rotating shaft portion in an attitude during use, the supply port is located on a side of an imaginary line that passes through the lowermost position of the second partition portion and is parallel to the direction of gravity, and the supply port is located on a side different from the side on which the communication port is located with respect to the imaginary line.

8. 8. The developing device according to claim 1, wherein the developing chamber is provided with a supply member that comes into contact with the developer carrier and supplies the developer to the developer carrier.

9. 9. The developing device according to claim 1, wherein the developer is a one-component non-magnetic developer.

10. 10. The developing device according to claim 1, wherein the developing device is detachable from an image forming device that forms an image.

11. an image carrier that carries a developer image; A process cartridge comprising the developing device according to any one of claims 1 to 10, and being detachable from an image forming apparatus.

12. 12. The process cartridge according to claim 11, wherein the developer carrier recovers the developer remaining on the image carrier after the developer image has been transferred from the image carrier.

13. At least one of the developing device according to any one of claims 1 to 10 and the process cartridge according to claim 11 or 12; A transfer member; An image forming apparatus comprising:

Images