Shutter mechanism and image forming apparatus

Abstract

The sheet-like material attached to the elastic sealing member is less likely to get caught on the edge of the shutter opening when the shutter is opened and closed. [Solution] A shutter opening 97a is formed that can communicate with a toner outlet 96a through which toner flows out, and a shutter 97 is provided that slides to open and close the toner outlet 96a. An opening 98a is formed that communicates with the toner outlet 96a, and an elastic sealing member 98 is provided that is attached to the edge so as to seal the gap between the shutter 97 and the edge of the toner outlet 96a. An opening 99a is formed that communicates with the toner outlet 96a, and a sheet-like member 99 is provided that is attached to the opposing surface 98x of the elastic sealing member 98 that faces the shutter 97. The sheet-like member 99 has a bent portion 99b formed that is bent away from the shutter 97, with the end in the direction corresponding to the upstream side in the opening direction of the shutter 97 as the bending source.

Description

Technical Field

[0001] This invention relates to a shutter mechanism for opening and closing a main body opening through which a fluid such as a developer flows in or out, and an image forming apparatus such as a copying machine, a printer, a facsimile machine, or a multifunction machine equipped with the same.

Background Art

[0002] Conventionally, in image forming apparatuses such as copying machines and printers, in order to prevent leakage of toner (developer) from a main body opening (toner supply port) provided in a toner supply device or a developing device, a shutter mechanism for opening and closing the main body opening has been widely known (see, for example, Patent Document 1).

[0003] In such a shutter mechanism, an elastic seal member made of foamed polyurethane or the like is adhered to the edge of the main body opening (toner supply port), and leakage of toner from the gap between the main body opening and the shutter is suppressed. Further, in order to reduce the sliding resistance with the elastic seal member when the shutter is opened and closed, a sheet-like member made of PET or the like is adhered to the surface of the elastic seal member facing the shutter.

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the conventional shutter mechanism, when the shutter is opened and closed, there is a possibility that the sheet-like member adhered to the elastic seal member may be caught by the edge of the shutter opening, causing problems such as the sheet-like member or the elastic seal member being rolled up or damaged.

[0005] This invention has been made to solve the above-described problems, and provides a shutter mechanism and an image forming apparatus in which the sheet-like member adhered to the elastic seal member is less likely to be caught by the edge of the shutter opening when the shutter is opened and closed. [[ID=...]]

Means for Solving the Problems

[0006] The shutter mechanism in this invention comprises: a shutter having a shutter opening that can communicate with a main body opening through which a fluid flows out or into, and a shutter that slides to open and close the main body opening; an elastic sealing member having an opening that communicates with the main body opening and being attached to the edge so as to seal the gap between the shutter and the edge of the main body opening; and a sheet-like member having an opening that communicates with the main body opening and being attached to the opposing surface of the elastic sealing member that faces the shutter, wherein the sheet-like member has a bent portion that is bent at a predetermined angle with respect to the opposing surface in a direction away from the shutter, with the end in the direction corresponding to the upstream side in the opening direction of the shutter being the bending source. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a shutter mechanism and an image forming apparatus in which the sheet-like member attached to the elastic sealing member is less likely to get caught on the edge of the main body opening when the shutter is opened and closed. [Brief explanation of the drawing]

[0008] [Figure 1] This is an overall configuration diagram showing an image forming apparatus according to an embodiment of the present invention. [Figure 2] This is a cross-sectional view showing the image-forming section. [Figure 3] This is an overall diagram showing the toner replenishment device and the developing device. [Figure 4] This is a cross-sectional view showing the shutter mechanism and its vicinity. [Figure 5] This is a cross-sectional view showing the elastic sealing member and the sheet-like member. [Figure 6] This is a perspective view showing the shutter mechanism. [Figure 7] This is a perspective view showing a shutter mechanism as a comparative example. [Figure 8] This is a perspective view showing the shutter mechanism as an example of modification 1. [Figure 9] This is a cross-sectional view showing the shutter mechanism and its vicinity, as a modified example (2). [Figure 10] This is a cross-sectional view showing the shutter, as a variation 3. [Figure 11] This is a cross-sectional view showing the shutter mechanism and its vicinity, as a modified example (modification 4). [Figure 12] This is a cross-sectional view showing the shutter mechanism and its vicinity, as a modified example (5). [Modes for carrying out the invention]

[0009] Hereinafter, embodiments for carrying out this invention will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and redundant explanations will be simplified or omitted as appropriate.

[0010] First, the overall configuration and operation of the image forming apparatus 100 will be explained using Figures 1 to 3. Figure 1 is a configuration diagram showing a printer as an image forming apparatus, Figure 2 is an enlarged view showing the image forming section, and Figure 3 is a configuration diagram showing its toner supply device and its vicinity. As shown in Figure 1, four roughly cylindrical toner containers 32Y, 32M, 32C, and 32K, corresponding to each color (yellow, magenta, cyan, and black), are detachably (replaceable) mounted on the mounting section 31 (toner container holder) located above the main body 100 of the image forming apparatus. Below each toner container 32Y, 32M, 32C, and 32K, toner supply hoppers 81Y, 81M, 81C, and 81K are respectively provided. Furthermore, an intermediate transfer unit 15 is positioned below the installation section 31. Opposite the intermediate transfer belt 8 of the intermediate transfer unit 15, image units 6Y, 6M, 6C, and 6K corresponding to each color (yellow, magenta, cyan, and black) are arranged side by side.

[0011] Referring to FIG. 2, the image forming unit 6Y corresponding to yellow is composed of a photosensitive drum 1Y (image carrier), a charging device 4Y disposed around the photosensitive drum 1Y, a developing device 5Y, a cleaning device 2Y, a charge removing device (not shown), etc. And on the photosensitive drum 1Y, an image forming process (charging process, exposure process, developing process, transfer process, cleaning process, charge removing process) is performed, and a yellow image is formed on the surface of the photosensitive drum 1Y.

[0012] Note that the other three image forming units 6M, 6C, and 6K have substantially the same configuration as the image forming unit 6Y corresponding to yellow, except that the color of the toner used is different, and images corresponding to their respective toner colors are formed. Hereinafter, the description of the other three image forming units 6M, 6C, and 6K will be appropriately omitted, and only the description of the image forming unit 6Y corresponding to yellow will be given.

[0013] Referring to FIG. 2, the photosensitive drum 1Y is rotationally driven in the clockwise direction of FIG. 2 by a motor. And at the position of the charging device 4Y, the surface of the photosensitive drum 1Y is uniformly charged (this is the charging process). Thereafter, the surface of the photosensitive drum 1Y reaches the irradiation position of the laser beam L emitted from the exposure device 7 (writing unit), and an electrostatic latent image corresponding to yellow is formed by exposure scanning at this position (this is the exposure process).

[0014] Thereafter, the surface of the photosensitive drum 1Y reaches the position facing the developing device 5Y, and the electrostatic latent image is developed at this position to form a yellow toner image (this is the developing process). Thereafter, the surface of the photosensitive drum 1Y reaches the position facing the intermediate transfer belt 8 and the primary transfer roller 9Y, and the toner image on the photosensitive drum 1Y is transferred onto the intermediate transfer belt 8 at this position (this is the primary transfer process). At this time, a small amount of untransferred toner remains on the photosensitive drum 1Y

[0015] Thereafter, the surface of the photosensitive drum 1Y reaches the position facing the cleaning device 2Y, and the untransferred toner remaining on the photosensitive drum 1Y is recovered at this position (this is the cleaning process). Finally, the surface of the photoreceptor drum 1Y reaches the position facing the charge eliminator (not shown), and the residual potential on the photoreceptor drum 1 is removed at this position. Thus, a series of image forming processes performed on the photoreceptor drum 1Y ends.

[0016] Note that the above-described image forming process is also performed in the other image forming units 6M, 6C, and 6K in the same manner as in the yellow image forming unit 6Y. That is, the laser light L based on the image information is irradiated onto the photoreceptor drums of the respective image forming units 6M, 6C, and 6K from the exposure device 7 disposed below the image forming unit. Specifically, the exposure device 7 emits the laser light L from the light source, scans the laser light L with a polygon mirror driven to rotate, and irradiates it onto the photoreceptor drum through a plurality of optical elements. Thereafter, the toner images of respective colors formed on the respective photoreceptor drums through the developing process are transferred and overlapped onto the intermediate transfer belt 8. Thus, a color image is formed on the intermediate transfer belt 8.

[0017] Here, the intermediate transfer unit 15 includes the intermediate transfer belt 8, four primary transfer rollers 9Y, 9M, 9C, 9K, a secondary transfer opposing roller 12, a cleaning backup roller 13, a tension roller 14, an intermediate transfer cleaning device 10, etc. The intermediate transfer belt 8 is stretched and supported by three rollers 12 to 14, and is endlessly moved in the direction of the arrow in FIG. 1 by the rotational drive of one roller 12.

[0018] The four primary transfer rollers 9Y, 9M, 9C, 9K sandwich the intermediate transfer belt 8 between the photoreceptor drums 1Y, 1M, 1C, 1K, respectively, to form primary transfer nips. A transfer bias opposite to the polarity of the toner is applied to the primary transfer rollers 9Y, 9M, 9C, 9K. Then, the intermediate transfer belt 8 travels in the direction of the arrow and sequentially passes through the primary transfer nips of the respective primary transfer rollers 9Y, 9M, 9C, 9K. Thus, the toner images of respective colors on the photoreceptor drums 1Y, 1M, 1C, 1K are primarily transferred and overlapped onto the intermediate transfer belt 8.

[0019] Subsequently, the intermediate transfer belt 8, on which the toner images of each color have been superimposed, reaches a position opposite the secondary transfer roller 19. At this position, the secondary transfer opposing roller 12 sandwiches the intermediate transfer belt 8 between itself and the secondary transfer roller 19, forming a secondary transfer nip. The four toner images formed on the intermediate transfer belt 8 are then transferred onto a sheet P, such as paper, which has been transported to the position of this secondary transfer nip. At this time, untransferred toner remains on the intermediate transfer belt 8 that has not been transferred to the sheet P.

[0020] Subsequently, the intermediate transfer belt 8 reaches the intermediate transfer cleaning device 10. At this location, any untransferred toner on the intermediate transfer belt 8 is collected. Thus, the series of transfer processes performed on the intermediate transfer belt 8 are completed.

[0021] Here, the sheet P that is transported to the secondary transfer nip position is transported from a paper feed device 26 located below the main body of the apparatus 100, via paper feed rollers 27 and a pair of registration rollers 28, etc. More specifically, the paper feeder 26 stores multiple sheets P of paper or other materials stacked together. When the paper feed roller 27 is driven to rotate counterclockwise in Figure 1, the top sheet P is fed towards the space between the registration rollers 28.

[0022] The sheet P, transported to the position of the register roller pair 28 (timing roller pair), temporarily stops at the roller nip of the register roller pair 28, where the rotational drive has been stopped. Then, in time with the color image on the intermediate transfer belt 8, the register roller pair 28 is driven to rotate, and the sheet P is transported toward the secondary transfer nip. In this way, the desired color image is transferred onto the sheet P.

[0023] Subsequently, the sheet P, on which the color image has been transferred at the secondary transfer nip, is transported to the fixing device 20. At this location, the color image transferred to the surface is fixed onto the sheet P by heat and pressure from the fixing roller and pressure roller. Subsequently, the sheet P is discharged outside the device via the rollers of the paper discharge roller pair 29. The sheet P discharged outside the device by the paper discharge roller pair 29 is sequentially stacked on the stacking unit 30 as an output image. Thus, the series of image formation processes in the image forming apparatus are completed.

[0024] Next, Figure 2 will provide a more detailed explanation of the configuration and operation of the developing device (replenishment unit) in the image-making section. The developing device 5Y consists of a developing roller 51 facing the photoreceptor drum 1Y, a doctor blade 52 facing the developing roller 51, two transport screws 55 arranged in the developer storage sections 53 and 54, a density detection sensor 56 for detecting the toner concentration in the developer, and the like. The developing roller 51 consists of a magnet fixed inside and a sleeve that rotates around the magnet. The developer storage sections 53 and 54 contain a two-component developer G (developer) consisting of a carrier and toner. Furthermore, the developing unit 5Y is configured to be detachable (replaceable) from the main image forming apparatus 100 (toner supply unit 90).

[0025] The developing apparatus 5Y, configured in this way, operates as follows: The sleeve of the developing roller 51 rotates in the direction of the arrow in Figure 2. The developer, which is supported on the developing roller 51 by the magnetic field formed by the magnet, moves along the developing roller 51 as the sleeve rotates. Here, the developer G in the developing device 5Y is adjusted so that the proportion of toner in the developer G (toner concentration) is within a predetermined range. Specifically, in accordance with the toner consumption in the developing device 5Y, the toner contained in the toner container 32Y is replenished (flows) into the developer storage section 54 via the toner replenishment device 90, which acts as a developer replenishment device. In this embodiment, the image forming apparatus 100 is provided with a shutter 97 that opens and closes the toner outlet 96a (main body opening) of the transport pipe 96 of the toner supply device 90, which discharges toner (fluid) toward the developing device 5Y (developer storage section 54). This will be explained in detail later using Figure 4 and other figures.

[0026] Subsequently, the toner supplied to the developer container 54 is mixed and agitated together with the developer by two transport screws 55, and circulates through the two developer containers 53 and 54 (movement in the longitudinal direction perpendicular to the paper surface in Figure 2). The toner in the developer is then attracted to the carrier by triboelectric charging and, together with the carrier, is supported on the developing roller 51 by the magnetic force formed on the developing roller 51. The developer supported on the developing roller 51 is transported in the direction of the arrow in Figure 3 to the position of the doctor blade 52. At this position, the amount of developer on the developing roller 51 is adjusted to the appropriate level, and then it is transported to the position opposite the photoreceptor drum 1Y (the developing area). Then, the toner is attracted to the latent image formed on the photoreceptor drum 1Y by the electric field formed in the developing area. After that, the developer remaining on the developing roller 51 reaches above the developer storage section 53 as the sleeve rotates, and at this position it is detached from the developing roller 51.

[0027] Next, Figure 3 will briefly explain the configuration and operation of the toner replenishment device 90 (replenishment device). The toner supply device 90 rotates the container body 33 of the toner container 32Y installed in the installation section 31 in a predetermined direction (the direction of the arrow in Figure 3), discharges the toner, which is stored inside the toner container 32Y as a fluid (powder), out of the container, and guides it to the developing device 5Y via the sub-hopper 70, thereby forming a toner supply path (toner transport path). Note that Figure 3 shows the toner container 32Y, toner replenishment device 90, and developing device 5Y arranged in different directions for easier understanding. In reality, in Figure 3, the toner container 32Y and a portion of the toner replenishment device 90 are arranged so that their longitudinal directions are perpendicular to the plane of the paper (see Figure 1). Also, the orientation and arrangement of the transport pipes 95 and 96 are simplified in the illustration.

[0028] The toner in each toner container 32Y, 32M, 32C, and 32K installed in the mounting section 31 of the image forming apparatus main body 100 is replenished into each developing unit as needed, via toner replenishment devices provided for each toner color, according to the toner consumption in each developing unit. The four toner replenishment devices have almost identical structures except for the different toner colors used in the image formation process. For details, please refer to Figure 3. When the toner container 32Y is set in the installation section 31 of the image forming apparatus body 100, the shutter member 36 of the toner container 32Y is pushed by the toner transport nozzle 91 of the image forming apparatus body 100, and the toner transport nozzle 91 is inserted into the inside of the toner container 32Y (container body 33). This enables the discharge of the toner contained inside the toner container 32Y (discharge via the toner transport nozzle 91). Furthermore, a gripping portion 33d is formed at the bottom of the toner container 32Y (the left side in Figure 3) to facilitate the operation of attaching the toner container 32Y to the installation portion 31. The user will hold the gripping portion 33d while setting the toner container 32Y into the installation portion 31 or removing the toner container 32Y from the installation portion 31.

[0029] Referring to Figures 3 and 4, the toner container 32Y is provided with a container body 33 having a spiral groove 33a formed in the longitudinal direction (the left-right direction in Figure 3, which is the rotation axis direction of the container body 33). Specifically, this spiral groove 33a is formed from the outer circumferential surface to the inner circumferential surface of the container body 33 and is for rotating the container body 33 to transport the toner inside the container body 33 from left to right in Figure 3. The toner transported from left to right in Figure 3 inside the container body 33 is discharged to the outside of the container via the toner transport nozzle 91. Furthermore, a gear 33b is formed on the outer circumferential surface of the top side (right side in Figure 3) of the container body 33, which meshes with the drive gear 110 of the image forming apparatus body 100. When the toner container 32Y is mounted on the installation section 31, the gear 33b of the container body 33 meshes with the drive gear 110 of the image forming apparatus body 100. When the drive motor 115 is driven, the drive (rotational drive) is transmitted from the drive gear 110 installed on the motor shaft to the gear 33b, causing the container body 33 to rotate. In other words, the drive motor 115 and the drive gear 110 function as a drive mechanism that rotates the container body 33.

[0030] On the other hand, referring to Figure 3, a transport screw 92 is installed inside the toner transport nozzle 91. The transport screw 92 is rotated by the motor 93, and the toner that flows from inside the toner container 32Y into the toner transport nozzle 91 is transported by the transport screw 92 from left to right in Figure 3. The toner is then discharged from the outlet of the toner transport nozzle 91 toward the hopper 81. Here, a hopper 81 is provided below the outlet of the toner transport nozzle 91 via a drop path 82. The toner stored in the hopper 81 is transported downstream to the developing device by a transport means. The configuration of the transport mechanism shown in Figure 3 is described below. A suction port 83 is provided at the bottom of the hopper 81, and this suction port 83 is connected to one end of the transport pipe 95 (tube). The transport pipe 95 is made of a flexible rubber material with low toner-receptive properties, and the other end is connected to the developer pump 60 (diaphragm pump). The developer pump 60 is connected to the developing device 5Y via the sub-hopper 70 and the transport pipe 96. In the toner supply device 90 configured in this way, the container body 33 of the toner container 32Y is rotated by the drive motor 115 (drive mechanism), and the toner contained inside the toner container 32Y is discharged to the outside of the container via the toner transport nozzle 91. The toner discharged from the toner container 32Y falls down the drop path 82 and is stored in the hopper 81. The toner stored in the hopper 81 is sucked up through the suction port 83 along with air when the developer pump 60 is operated, and is transported from the developer pump 60 to the sub-hopper 70 via the transport pipe 95. The toner transported to and stored in the sub-hopper 70 is then supplied to the developer device 5Y as needed via the transport pipe 96. In other words, the toner in the toner container 32Y is transported in the direction of the dashed arrow in Figure 3. The transport means is not limited to those described above. For example, the toner stored in the hopper 81 may be directly transported to the developing device 5Y by a screw or the like provided in the hopper 81.

[0031] The toner level detection sensor 86 is used to indirectly detect when the toner stored inside the toner container 32Y is empty (toner end state) or close to that state (toner near end state), and is installed near the suction port 83. Based on the detection result of the toner level detection sensor 86, toner is discharged from the toner container 32Y. For more details, the toner level detection sensor 86 can be a piezoelectric sensor, a transmitted light sensor, or the like. The height of the detection surface of the toner level detection sensor 86 is set so that the amount of toner accumulated above the suction port 83 (accumulation height) reaches the target value. Based on the detection results of the toner level detection sensor 86, the driving timing and driving time of the drive motor 115 that rotates the toner container 32Y (container body 33) are controlled. Specifically, if the toner level detection sensor 86 determines that there is no toner at that position, the drive motor 115 is driven for a predetermined time, and if the toner level detection sensor 86 determines that there is toner at that position, the drive of the drive motor 115 is stopped. Even if such control is repeated, if the toner level detection sensor 86 continuously detects that there is no toner at that position, it is determined that the toner contained inside the toner container 32Y is empty (toner end state) or close to that state (toner near end state).

[0032] The shutter mechanisms 97-99, which are characteristic of the image forming apparatus 100 in this embodiment, will be described in detail below with reference to Figures 4-6 and others. As shown in Figure 4 (and Figure 2), the image forming apparatus 100 in this embodiment is provided with shutter mechanisms 97 to 99 for opening and closing the toner supply path from the toner supply device 90 (transport pipe 96) to the developing device 5Y (developer storage section 54). Referring to Figures 4 to 6, this shutter mechanism consists of a shutter 97, an elastic sealing member 98, a sheet-like member 99, and the like.

[0033] The shutter 97 slides open and closes the toner outlet 96a, which is the main opening formed in the transport pipe 96 (housing) of the toner supply device 90 (this is horizontal movement in the left-right direction in Figure 4). In this embodiment, the shutter 97 is slidably installed in the toner supply device 90, which serves as a developer supply device. In the toner supply device 90, a guide holding part (not shown) is installed near the transport pipe 96 to hold the shutter 97 in a slidable position. With the developer storage unit 54 of the developer device 5Y connected to the transport pipe 96 of the toner supply device 90 (the toner inlet 54a of the developer storage unit 54 is located below the toner outlet 96a), the shutter 97 slides to open and close the toner outlet 96a. Furthermore, the sliding movement of the shutter 97 (opening and closing of the toner outlet 96a) can be performed manually by the user using an operating lever, or it can be performed automatically by detecting the connection status between the transport tube 96 and the developer storage section 54 using a sensor and driving the pinion rack mechanism in forward or reverse directions.

[0034] Furthermore, the shutter 97 has a shutter opening 97a that can communicate with a toner outlet 96a (main body opening) from which toner (a one-component developer) as a fluid is discharged. This toner outlet 96a (main body opening) is formed in a toner supply device 90 (transport pipe 96) that discharges toner as a developer towards the inside of the developing device 5Y.

[0035] Specifically, when the shutter 97 is in the position shown in Figure 4(A), the shutter opening 97a is not in communication with the toner outlet 96a (and the toner inlet 54a, and the openings 98a and 99a of the elastic sealing member 98 and sheet-like member 99, which will be described later) (the shutter main surface 97x (see Figure 6) is blocking the toner outlet 96a and the toner inlet 54a). As a result, the transfer of toner (fluid) from the toner outlet 96a to the toner inlet 54a becomes impossible. This state occurs when the image formation process, which was explained earlier using Figures 1 to 3, is not performed, and is particularly common when the developing device 5 is not properly set up, such as when it is removed from the toner supply device 90 (image forming device main body 100). When removing the developing unit 5Y from the toner supply unit 90 (for example, when disconnecting the toner outlet 96a from the toner inlet 54a), the shutter 97 can be used to close the toner outlet 96a, thereby preventing toner leakage from the toner outlet 96a. In contrast, when the shutter 97 is moved to the position shown in Figure 4(B), the shutter opening 97a is in communication with the toner outlet 96a (and the toner inlet 54a, and the openings 98a and 99a of the elastic sealing member 98 and sheet-like member 99, which will be described later). This allows for the transfer of toner (fluid) from the toner outlet 96a to the toner inlet 54a. This state is when the image formation process, which was explained earlier using Figures 1 to 3, is executed. Note that the dashed arrows in Figure 4(A) and the solid arrows in Figure 6 indicate the opening direction of the shutter 97, while the opposite direction indicates the closing direction of the shutter 97.

[0036] Referring to Figures 4 to 6, the elastic sealing member 98 is attached to the edge (periphery) of the shutter 97 via double-sided tape or the like to seal the gap between the shutter 97 and the edge (periphery) of the toner outlet 96a (main body opening). The elastic sealing member 98 also has an opening 98a that communicates with the toner outlet 96a (main body opening). More specifically, the elastic sealing member 98 is a roughly rectangular sealing material made of an elastic material such as foamed polyurethane with a thickness of several millimeters to about 10 millimeters, and is intended to seal the gap between the shutter 97 and the edge of the toner outlet 96a (the surrounding area excluding the toner outlet 96a). In addition, the elastic sealing member 98 has an opening 98a that is the same size as (or slightly larger than) the toner outlet 96a so as not to block the toner outlet 96a.

[0037] Referring to Figures 4 to 6, the sheet-like member 99 is attached to the opposing surface 98x (lower surface) of the elastic sealing member 98 that faces the shutter 97 via double-sided tape or the like. The sheet-like member 99 also has an opening 99a that communicates with the toner outlet 96a (main body opening) via the opening 98a of the elastic sealing member 98. More specifically, the sheet-like member 99 is made of a low-friction material such as PET (polyethylene terephthalate) with a thickness of about 0.05 to 1.5 mm and is a flexible member that can deform in accordance with the elastic deformation of the elastic sealing member 98. Its purpose is to reduce the sliding resistance between the elastic sealing member 98 and the shutter 97 due to the sliding movement (opening and closing operation) of the shutter 97 while maintaining the sealing performance of the elastic sealing member 98. Furthermore, the sheet-like member 99 has an opening 99a that is the same size as (or slightly larger than) the toner outlet 96a (and the opening 98a of the elastic sealing member 98) so as not to block the toner outlet 96a (and the opening 98a of the elastic sealing member 98).

[0038] Referring to Figures 4 to 6, in the shutter mechanisms 97 to 99 of this embodiment, the sheet-like member 99 has a bent portion 99b that is bent at a predetermined angle with respect to the opposing surface 98x of the elastic sealing member 98 (the surface facing the shutter 97), with the end in the direction corresponding to the upstream side in the opening direction (or the downstream side in the closing direction) of the shutter 97 (the left end in Figures 4 and 5) as the bending source, in the direction away from the shutter 97 (upwards in Figures 4 and 5). More specifically, the sheet-like member 99 differs from the substantially planar sheet-like member 199 shown as a comparative example in Figure 7 in having a substantially L-shaped cross-section. In other words, the sheet-like member 99 has a bent portion 99b that extends upward from a flat end (the end located upstream of the opening direction of the shutter 97, indicated by the arrow in Figure 6) formed to be aligned with (adhered to) the opposing surface 98x of the elastic sealing member 98. That is, the bent portion 99b of the sheet-like member 99 is located opposite the edge portion 97z (the upstream edge portion in the opening direction) of the shutter 97 in the closed state (as shown in Figure 4(A)). Such a bent portion 99b can be formed by bending a planar sheet.

[0039] As described above, in this embodiment, the shutter mechanisms 97-99 are provided with a bent portion 99b at the upstream end of the sheet-like member 99 in the opening direction. Therefore, when the shutter 97 is opened or closed (especially when opened in the direction of the dashed arrow in Figure 4 or the arrow in Figure 6), the sheet-like member 99 attached to the elastic sealing member 98 is less likely to get caught on the edge portion 97z of the shutter opening 97a. As a result, problems such as the sheet-like member 99 or the elastic sealing member 98 being curled up or damaged are less likely to occur.

[0040] More specifically, as shown in Figure 7 as a comparative example, in a shutter mechanism where a substantially flat sheet-like member 199 without a bent portion is attached to an elastic sealing member 98, when the shutter opening 97a approaches the opposing position, the difference in height between the shutter main surface 97x and the shutter opening 97a (resulting in parts that contact the shutter main surface 97x and parts that do not) causes the sheet-like member 199, together with the elastic sealing member 98, to deform downward in an arc shape as enclosed by the dashed line. Then, when the shutter 97 is opened (movement in the direction of the arrow in Figure 7), the portion of the sheet-like member 99 (or elastic sealing member 98) that has deformed downward in an arc shape catches on the edge portion 97z of the shutter opening 97a, causing the sheet-like member 199 to curl up or otherwise become damaged. When such a malfunction occurs, the sheet-like member 199 and the elastic sealing member 98 will no longer function properly, resulting in toner leakage to the outside from the toner outlet 96a. In contrast, in this embodiment, a bent portion 99b is provided at the upstream end of the sheet-like member 99 in the opening direction. This increases the rigidity of that portion, making it less likely for the sheet-like member 99 to deform downward into an arc shape together with the elastic sealing member 98 (making it easier to maintain a substantially flat state on the lower surface). Therefore, when the shutter 97 is opened (movement in the direction of the arrow in Figure 6), it is less likely to get caught on the edge portion 97z of the shutter opening 97a, thus reducing the likelihood of the aforementioned problems occurring. Furthermore, in this embodiment, since a bent portion 99b is provided at the upstream end of the sheet-like member 99 in the opening direction, even if the sheet-like member 99 deforms downward into an arc shape together with the elastic sealing member 98, when the shutter 97 is opened, the bent portion 99b will be in surface contact with the edge portion 97z of the shutter opening 97a. This makes it difficult for forces that would peel off the sheet-like member 99 or the elastic sealing member 98 to occur, thus reducing the likelihood of the aforementioned problems.

[0041] In this embodiment, in order to reduce the deformation of the bent portion 99b due to the compressive deformation of the elastic sealing member 98, the bent portion 99b is configured not to be attached to the side surface of the elastic sealing member 98. In contrast, if the deformation of the bent portion 99b due to the compressive deformation of the elastic sealing member 98 is minor, attaching the bent portion 99b to the side surface of the elastic sealing member 98 makes it easier to maintain the posture of the bent portion 99b even if it gets caught on the edge portion 97z when the shutter is opened.

[0042] Referring to Figure 5, etc., in this embodiment, the bent portion 99b of the sheet-like member 99 is bent at approximately 90 degrees with respect to the opposing surface 98x (which is approximately a horizontal plane) of the elastic sealing member 98. In other words, the bent portion 99b is formed to stand upright in an approximately vertical direction. By bending the bent portion 99b nearly vertically in this way, even if the bent portion 99b comes into contact with the edge portion 97z, the likelihood of the bent portion 99b deforming and getting caught on the edge portion 97z is reduced compared to bending it at a smaller angle. However, even if the bending angle of the bent portion 99b is 90 degrees or less, if it is close to that angle, a similar effect to the one described above can be obtained.

[0043] <Example 1> As shown in Figure 8, in the modified example 1, the shutter mechanism 97-99 has a shorter length in the width direction (indicated by the dashed double arrow in Figure 8, which is perpendicular to the opening and closing direction) of the bent portion 99b of the sheet-like member 99 compared to that in Figure 6. More specifically, the sheet-like member 99 shown in Figure 6 is formed such that the widthwise range of the bent portion 99b is the same as the widthwise range of the elastic sealing member 98, similar to the flat portion that contacts the shutter main surface 97x. In contrast, in the modified example 1 shown in Figure 8, the sheet-like member 99 has a flat portion in contact with the main shutter surface 97x that is equivalent to the widthwise range of the elastic sealing member 98, but the bent portion 99b is formed to be within the range included in the widthwise range and to include the widthwise range of the shutter opening 97a. Even with this configuration, when the shutter 97 is opened (movement in the direction of the arrow in Figure 8), the sheet-like member 99 (bent portion 99b) is less likely to get caught on the edge portion 97z of the shutter opening 97a, thus reducing the likelihood of the sheet-like member 99 curling up. Furthermore, in the modified example 1, the amount of material required to manufacture the sheet-like member 99 can be reduced by the amount by which the widthwise length of the bent portion 99b is shortened.

[0044] <Modification 2> As shown in Figure 9(A), in the shutter mechanism 97-99 of the modified example 2, the bent portion 99b of the sheet-like member 99 is bent within a range in the thickness direction that does not exceed the thickness of the elastic sealing member 98 when it is installed in the gap between the shutter 97 and the edge of the toner outlet 96a (in a compressed and deformed state). In other words, in the shutter mechanisms 97-99 under actual use, a certain gap δ (a gap in the height direction) is formed between the bent portion 97b and the edge of the toner outlet 96a (the bottom surface of the transport pipe 96). With this configuration, even if the elastic sealing member 98 is compressed between the shutter 97 and the edge of the toner outlet 96a, it becomes less likely that the upper end of the bent portion 99b will interfere with the edge of the toner outlet 96a (the bottom surface of the transport pipe 96), causing the bent portion 99b to buckle. In another configuration, the shutter mechanisms 97-99 shown in Figure 9(B) have a sheet-like member 99 whose bent end protrudes upstream in the opening direction (left side in Figure 9(B)) from the transport pipe 96, which serves as the housing where the toner outlet 96a (main body opening) is formed. In other words, the ends of the elastic sealing member 98 and the sheet-like member 99 shown in Figure 9(B) do not coincide approximately with the position of the end of the transport pipe 96 on the upstream side in the opening direction, but rather are located further upstream in the opening direction (in the direction indicated by the solid arrow in Figure 9(B)). Even with this configuration, the elastic sealing member 98 is compressed between the shutter 97 and the edge of the toner outlet 96a, making it less likely for the upper end of the bent portion 99b to interfere with the edge of the toner outlet 96a (the bottom surface of the transport pipe 96) and cause the bent portion 99b to buckle.

[0045] <Variation 3> As shown in Figure 10(A), in the shutter mechanism 97-99 of modified example 3, the shutter opening 97a of the shutter 97 has a chamfered edge portion 97z on the upstream side in the opening direction (the left side in Figure 10). Furthermore, in the shutter mechanisms 97-99 shown as an alternative configuration in Figure 10(B), the shutter opening 97a of the shutter 97 has an edge portion 97z on the upstream side in the opening direction that is formed in an R-shape. By configuring the device in this way, even if the bent portion 99b comes into contact with the edge portion 97z when the shutter 97 is opened, it becomes less likely that the bent portion 99b will get caught on the edge portion 97z, which is formed in a C-shape or R-shape.

[0046] <Modification 4> As shown in Figure 11, the shutter mechanisms 97-99 in the modified example 4 are configured such that the shutter 97 opens and closes the toner outlet 96a in conjunction with the operation of attaching and detaching the developing device 5Y (toner inlet 54a of the developer storage unit 54) to the toner supply device 90 (toner outlet 96a of the transport pipe 96). Although not shown in the diagram, the shutter 97, which is slidably mounted on the toner supply device 90 (image forming apparatus main body 100), is positioned to close the toner outlet 96a due to the biasing force of the spring when the developing device 5Y is not set on the toner supply device 90 (this is the state shown in Figure 11(A)). In contrast, as the developing device 5Y is set on the toner supply device 90 in the direction of the white arrow, a push part formed on the developing device 5Y pushes the shutter 97 in the direction of the dashed arrow, causing the shutter 97 to move to a position where it opens the toner outlet 96a, resisting the biasing force of the spring mentioned above (this is the state shown in Figure 11(B)). Furthermore, when the developing unit 5Y is removed from the toner supply unit 90, the reverse operation of the installation process described above will occur. Furthermore, in the shutter mechanisms 97-99 configured in this way, when the shutter 97 is opened and closed, the sheet-like member 99 attached to the elastic sealing member 98 is less likely to get caught on the edge portion 97z of the shutter opening 97a.

[0047] <Modification 5> As shown in Figure 12, in the modified example 5, the image forming apparatus 100 is provided with a second set of shutter mechanisms 57-59 for opening and closing the toner inlet 54a, in addition to the shutter mechanisms 97-99 for opening and closing the toner outlet 96a, as explained using Figures 4-6, etc. More specifically, the second shutter mechanism is designed to prevent toner leakage from the toner inlet 54a when the developing unit 5Y is removed from the toner supply unit 90, and consists of a shutter 57, an elastic sealing member 58, a sheet-like member 59, and the like. In this case, the toner inlet 54a formed in the developing unit 5Y (developer storage unit 54) into which toner (developer) as a fluid flows from the toner supply unit 90 (developer supply unit) functions as a main body opening. The shutter 57 is slidably installed in the developing unit 5Y and has a shutter opening 57a that can communicate with the toner inlet 54a. Furthermore, the elastic sealing member 58 is attached to the edge of the shutter 57 to seal the gap between the shutter 57 and the edge of the toner inlet 54a, and an opening is formed that communicates with the toner inlet 54a. Furthermore, the sheet-like member 59 is attached to the opposing surface of the elastic sealing member 58 that faces the shutter 57, and has an opening that communicates with the toner inlet 54a. The sheet-like member 59 has a bent portion 59b formed on it, which is bent at a predetermined angle relative to the opposing surface of the elastic sealing member 58 in the direction away from the shutter 57 (downward in Figure 12), with the end of the sheet-like member 59 in the direction corresponding to the upstream side in the opening direction of the shutter 57 (left side in Figure 12) as the bending source. In the second shutter mechanism 57-59 configured in this way, the sheet-like member 59 attached to the elastic sealing member 58 is less likely to get caught on the edge of the shutter opening 57a when the shutter 57 is opened and closed.

[0048] As described above, the shutter mechanism in this embodiment has a shutter opening 97a that can communicate with the toner outlet 96a (main body opening) through which the toner (fluid) flows out, and a shutter 97 that slides to open and close the toner outlet 96a. In addition, an opening 98a that communicates with the toner outlet 96a is formed, and an elastic sealing member 98 is attached to the edge to seal the gap between the shutter 97 and the edge of the toner outlet 96a. Furthermore, an opening 99a that communicates with the toner outlet 96a is formed, and a sheet-like member 99 is attached to the opposing surface 98x of the elastic sealing member 98 that faces the shutter 97. The sheet-like member 99 has a bent portion 99b formed by bending the end corresponding to the upstream side in the opening direction of the shutter 97 at a predetermined angle with respect to the opposing surface 98x in a direction away from the shutter 97. This makes it less likely for the sheet-like member 99 attached to the elastic sealing member 98 to get caught on the edge portion 97z of the shutter opening 97a when the shutter 97 is opened and closed.

[0049] In this embodiment, the present invention was applied to shutter mechanisms 97-99 that open and close the toner outlet 96a (main body opening) of the transport pipe 96 through which toner (one-component developer) flows out as a fluid. However, the toner container to which the present invention is applied is not limited to this. For example, the present invention can also be applied to shutter mechanisms that open and close the main body opening through which a two-component developer consisting of toner and a carrier flows out as a fluid, shutter mechanisms that open and close the main body opening through which a fluid such as fresh toner, recycled toner, or untransferred toner flows out or into, and shutter mechanisms that open and close the main body opening through which a fluid other than developer flows out or into. Furthermore, although the image forming apparatus 100 in this embodiment is configured so that the developing device 5Y can be attached to and detached (replaced) independently from the toner supply device 90, it is also possible to configure the apparatus so that the developing device 5Y is integrated into a process cartridge (a unit in which two or more devices that constitute the image forming section are integrally formed) to which the process cartridge is attached to and detached (replaced) from the toner supply device 90. Furthermore, in this embodiment, a bottle-shaped toner container 32Y is installed, and the present invention is applied to shutter mechanisms 97-99 that open and close the toner outlet 96a (main body opening) of a toner supply device 90 using a developer pump 60. However, the configuration of the toner supply device and toner container is not limited to these. Furthermore, even in such cases, it is possible to obtain effects that are almost the same as those of this embodiment.

[0050] It should be noted that the present invention is not limited to this embodiment, and within the scope of the technical concept of the present invention, this embodiment can be modified as appropriate in ways other than those suggested here. Furthermore, the number, position, shape, etc. of the above-mentioned components are not limited to this embodiment, and can be set to a number, position, shape, etc. that is suitable for carrying out the present invention. [Explanation of symbols]

[0051] 5Y developing machine, 54 Developer storage section, 54a Toner inlet, 57 shutters, 57a Shutter opening, 58 Elastic sealing member, 59 Sheet-like member, 59b Bent section, 90 Toner replenishment device (developer replenishment device), 96 Conveyor pipe (housing section), 96a Toner outlet (main unit opening), 97 shutters, 97a Shutter opening, 97x Shutter main surface, 97z edge section, 98 Elastic sealing member, 98a Opening (seal opening), 98x opposing surfaces, 99 Sheet-like member, 99a Opening (sheet opening), 99b Bent section, 100 Image forming apparatus (image forming apparatus main unit).

[0052] Furthermore, the embodiments of the present invention can also be, for example, combinations of appendices 1 to 8 as follows. (Note 1) A shutter opening is formed that can communicate with the main body opening through which a fluid flows out or into, and the shutter slides to open and close the main body opening, An elastic sealing member is attached to the edge portion so as to seal the gap between the shutter and the edge portion of the main body opening, and an opening is formed therein that communicates with the main body opening. An opening communicating with the main body opening is formed, and a sheet-like member is attached to the opposing surface of the elastic sealing member that faces the shutter, Equipped with, The shutter mechanism is characterized in that the sheet-like member has a bent portion which is bent at a predetermined angle with respect to the opposing surface in a direction away from the shutter, with the end in the direction corresponding to the upstream side in the opening direction of the shutter being the bending source. (Note 2) The shutter mechanism according to Appendix 1, characterized in that the bent portion of the sheet-like member is bent at approximately 90 degrees with respect to the opposing surface. (Note 3) The shutter mechanism according to Appendix 1 or Appendix 2, characterized in that the bent portion of the sheet-like member is bent within a range in the thickness direction that does not exceed the thickness of the elastic sealing member when installed in the gap. (Note 4) The shutter mechanism according to any one of the appendices 1 to 3, characterized in that the end portion of the sheet-like member that is the source of the bend protrudes from the housing portion in which the main body opening is formed toward the upstream side in the opening direction. (Note 5) The shutter mechanism according to any one of the appendices 1 to 4, characterized in that the edge portion on the upstream side in the opening direction of the shutter opening is formed in a C-shape or R-shape. (Note 6) The shutter mechanism according to any one of the appendices 1 to 5, characterized in that the sheet-like member is formed of a low-friction material. (Note 7) The aforementioned fluid is a developer, The opening in the main body is formed in a developer supply device that discharges the developer towards the inside of the developing device, or in the developing device into which the developer flows from the developer supply device. The shutter mechanism according to any one of the appendices 1 to 6, characterized in that the shutter is installed in the developer supply device or the developing device. (Note 8) An image forming apparatus characterized by being equipped with a shutter mechanism described in any of the appendices 1 to 7. [Prior art documents] [Patent Documents]

[0053] [Patent Document 1] Patent No. 6198133

Claims

1. A shutter opening is formed that can communicate with the main body opening through which a fluid flows out or into, and the shutter slides to open and close the main body opening, An elastic sealing member is attached to the edge portion so as to seal the gap between the shutter and the edge portion of the main body opening, and an opening is formed therein that communicates with the main body opening. An opening communicating with the main body opening is formed, and a sheet-like member is attached to the opposing surface of the elastic sealing member that faces the shutter, Equipped with, The shutter mechanism is characterized in that the sheet-like member has a bent portion which is bent at a predetermined angle with respect to the opposing surface in a direction away from the shutter, with the end in the direction corresponding to the upstream side in the opening direction of the shutter being the bending source.

2. The shutter mechanism according to claim 1, characterized in that the bent portion of the sheet-like member is bent at approximately 90 degrees with respect to the opposing surface.

3. The shutter mechanism according to claim 1 or 2, characterized in that the bent portion of the sheet-like member is bent within a range in the thickness direction that does not exceed the thickness of the elastic sealing member when installed in the gap.

4. The shutter mechanism according to claim 1 or 2, characterized in that the end portion of the sheet-like member that is the source of the bend protrudes upstream in the opening direction from the housing portion in which the main body opening is formed.

5. The shutter mechanism according to claim 1 or 2, characterized in that the edge portion on the upstream side in the opening direction of the shutter opening is formed in a C-shape or R-shape.

6. The shutter mechanism according to claim 1 or 2, characterized in that the sheet-like member is formed of a low-friction material.

7. The aforementioned fluid is a developer, The opening in the main body is formed in a developer supply device that discharges the developer towards the inside of the developing device, or in the developing device into which the developer flows from the developer supply device. The shutter mechanism according to claim 1 or 2, characterized in that the shutter is installed in the developer supply device or the developing device.

8. An image forming apparatus characterized by being equipped with the shutter mechanism described in claim 1 or claim 2.

Images