Image forming apparatus and storage cartridge

Abstract

To provide an image forming apparatus capable of recovering degraded toner accumulated in the developing room. [Solution] An image forming apparatus comprising: a rotatably supported developing roller; a rotatable rotary having a developing chamber that includes the developing roller and has a receiving opening; and a toner cartridge that is detachable from the rotary and has an opening for containing toner and supplying toner to the developing chamber; and an image forming apparatus comprising a refresh cartridge that is detachable from the rotary and has a means for discharging toner from the developing chamber, wherein when the refresh cartridge is installed, the toner from the developing chamber is discharged into the refresh cartridge.

Description

Technical Field

[0006] , , ,

[0001] The present invention relates to an image forming apparatus and a storage cartridge.

Background Art

[0002] In an electrophotographic image forming apparatus, a rotary development method is known in which a color image is formed by rotating a rotary body provided with a plurality of developing chambers including a developing roller. Patent Document 1 describes an image forming apparatus including a rotary body provided with a plurality of developing chambers including a developing roller, and a plurality of toner cartridges each detachable from the rotary body.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

[0007] According to the present invention, it is possible to provide an image forming apparatus capable of recovering deteriorated toner accumulated in the developing chamber. [Brief explanation of the drawing]

[0008] [Figure 1] Schematic diagram of the image forming apparatus in Example 1 [Figure 2] Configuration diagram of the image forming apparatus in Example 1 [Figure 3] Schematic diagram of the developing unit, toner cartridge, and tray of Example 1 [Figure 4A] Cross-sectional view of the image forming apparatus in Example 1 [Figure 4B]Cross-sectional view of the image forming apparatus according to Embodiment 1 [Figure 5] Perspective view of the rotary body according to Embodiment 1 [Figure 6] Schematic configuration diagram of the developing unit according to Embodiment 1 [Figure 7] Explanatory diagram when toner is supplied to the developing unit according to Embodiment 1 [Figure 8] Cross-sectional view of the developing unit at each phase with the rotary body according to Embodiment 1 [Figure 9] Cross-sectional view of the refresh cartridge according to Embodiment 1 [Figure 10A] Cross-sectional view of the developing unit, refresh cartridge, and tray according to Embodiment 1 [Figure 10B] Cross-sectional view of the developing unit, refresh cartridge, and tray according to Embodiment 1 [Figure 11] Cross-sectional view of the refresh cartridge according to Embodiment 2 [Figure 12A] Cross-sectional view of the developing unit, refresh cartridge, and tray according to Embodiment 2 [Figure 12B] Cross-sectional view of the developing unit, refresh cartridge, and tray according to Embodiment 2 [Figure 13] Cross-sectional view of the developing unit at each phase with the rotary body according to Embodiment 2.

Mode for Carrying Out the Invention

[0009] Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings.

[0010] [Embodiment 1] Using FIGS. 1 to 7, the image forming apparatus 1 according to Embodiment 1 will be described. In the following description and each drawing, when the image forming apparatus 1 is installed on a horizontal plane, the vertical direction (gravity direction) is defined as the Z direction. A direction intersecting the Z direction and in the direction of the rotation axis 90C of the rotary body 90 (the rotary axis direction of the rotary body), which will be described later, is defined as the Y direction. A direction intersecting both the Z direction and the Y direction is defined as the X direction. The X direction and the Y direction are preferably horizontal directions. Also, the X direction, the Y direction, and the Z direction are preferably orthogonal to each other. Further, if necessary, the directions of the arrows X, Y, and Z shown in each drawing are represented as the +X side, the +Y side, and the +Z side, respectively, and the opposite sides are represented as the -X side, the -Y side, and the -Z side, respectively.

[0011] (Overall Configuration of Image Forming Apparatus) First, the overall configuration of the image forming apparatus 1 will be described. The image forming apparatus 1 is a laser beam printer that forms an image on a sheet S by an electrophotographic method. More specifically, the image forming apparatus 1 is a color laser beam printer including four developing units 50y, 50m, 50c, and 50k. As the sheet S (recording medium), various sheet materials with different sizes and materials can be used, such as paper including plain paper and thick paper, plastic film, cloth, sheet materials with surface treatment such as coated paper, and special-shaped sheet materials such as envelopes and index paper.

[0012] Using FIGS. 1, FIGS. 2, and FIGS. 3, the schematic configuration and the image forming operation of the image forming apparatus 1 will be described. FIG. 1 is a schematic view showing a cross-sectional configuration of the image forming apparatus 1. FIG. 2 is a diagram for explaining the drive source of the image forming apparatus 1. FIG. 3 is a conceptual diagram showing a configuration for supplying toner from the toner cartridge 70 to the developing unit 50.

[0013] As shown in FIG. 1, the image forming apparatus 1 includes an image forming apparatus main body (hereinafter, the main body) 1A and toner cartridges 70y, 70m, 70c, and 70k as developer cartridges detachable from the main body 1A. The main body 1A of this embodiment is the portion of the image forming apparatus 1 excluding the toner cartridges 70y, 70m, 70c, and 70k.

[0014] The main body 1A of the image forming apparatus 1 has an electrophotographic photoreceptor (hereinafter referred to as a photosensitive drum) 2 having a drum shape (cylindrical shape) as an image carrier for holding an electrostatic latent image. Around the photosensitive drum 2 are a charging roller 3, a scanner 4 as an exposure device, and a cleaning unit 6.

[0015] The charging roller 3 is an example of a charging means for uniformly charging the photosensitive drum 2. The scanner 4 is an example of an exposure means for exposing the photosensitive drum 2 by irradiating it with laser light corresponding to image information. By irradiating the charged photosensitive drum 2 with laser light, an electrostatic latent image is formed on the surface of the photosensitive drum 2. The cleaning unit 6 is an example of a cleaning means for removing toner remaining on the surface of the photosensitive drum 2.

[0016] Furthermore, the main body of the device 1A includes a sheet storage section 300, a pickup roller 310, a feed roller 311, a separation roller 312, a transport roller pair 320, a secondary transfer roller 12, a fixing device 40, and an intermediate transfer unit 10. The pickup roller 310 is an example of a feeding means for feeding the sheets S. The feed roller 311 and the separation roller 312 are examples of a separation transport unit that transports the sheets S one by one while separating them by frictional force. The secondary transfer roller 12 is an example of a transfer means for transferring an image from the intermediate transfer belt 10a to the sheets S.

[0017] The intermediate transfer unit 10 includes an intermediate transfer belt 10a, a belt drive roller 10b, a tension roller 10c, a cleaning device 13, and a primary transfer roller 11. The intermediate transfer belt 10a is an example of an intermediate transfer body that carries the image transferred from the photosensitive drum 2 (primary transfer) and transports it for transfer to the sheet S (secondary transfer). The intermediate transfer belt 10a is stretched over the belt drive roller 10b and the tension roller 10c. The belt drive roller 10b is a drive member that transports the intermediate transfer belt 10a by being rotationally driven by a drive source.

[0018] Furthermore, the main unit 1A of the apparatus has a rotary body (rotary, rotating body) 90 having developing units 50y, 50m, 50c, and 50k. In this embodiment, trays 80y, 80m, 80c, and 80k are attached to the rotary body 90 as support parts. Toner cartridges 70y, 70m, 70c, and 70k are removablely mounted on the trays 80y, 80m, 80c, and 80k. Toner cartridge 70k is an example of a first toner cartridge. Toner cartridge 70m is an example of a second toner cartridge. Toner cartridge 70y is an example of a third toner cartridge. Toner cartridge 70c is an example of a fourth toner cartridge.

[0019] Tray 80k is an example of a first support member that supports the first toner cartridge. Tray 80m is an example of a second support member that supports the second toner cartridge. Tray 80y is an example of a third support member that supports the third toner cartridge. Tray 80c is an example of a fourth support member that supports the fourth toner cartridge. Although tray 80 is shown here as a support part, the toner cartridge 70 may be detachably mounted directly to the rotary body 90 without using tray 80.

[0020] The developing units 50y, 50m, 50c, and 50k are examples of developing means that develop (reveal) an electrostatic latent image formed on the photosensitive drum 2 into a toner image using toner of the corresponding color. The developing units 50y, 50m, 50c, and 50k develop the electrostatic latent image formed on the photosensitive drum 2 using yellow toner, magenta toner, cyan toner, or black toner, respectively.

[0021] The developing unit 50y includes a developing roller 51y, a supply roller 52y, and a developing blade 54. The developing roller 51y is a developer carrier that carries toner as a developer, rotates, and supplies it to the photosensitive drum 2. The supply roller 52y is positioned in contact with the developing roller 51y and is a supply member that supplies toner to the developing roller 51. The developing blade 54 is a regulating member that regulates the thickness of the toner layer carried on the developing roller 51y. The other developing units 50m, 50c, and 50k also include similar developing rollers 51m, 51c, 51k, supply rollers 52m, 52c, 52k, and a developing blade 54.

[0022] The rotary unit 90 is fitted with toner cartridges 70y, 70m, 70c, and 70k, which correspond to the developing units 50y, 50m, 50c, and 50k. Inside the toner cartridges 70y, 70m, 70c, and 70k are yellow toner, magenta toner, cyan toner, and black toner, respectively, to replenish the developing units 50y, 50m, 50c, and 50k. The black toner is an example of the first toner, and the magenta toner is an example of the second toner.

[0023] Here, the rotary body 90 has a rotary frame 90f that supports the developing units 50y, 50m, 50c, and 50k. The developing units 50y, 50m, 50c, and 50k are supported by the rotary frame 90f, which is a rotatable rotating support.

[0024] Furthermore, trays 80y, 80m, 80c, and 80k are attached to the rotary body 90. The part consisting of the rotary body 90 and trays 80y, 80m, 80c, and 80k can be called the rotary unit 90U. In other words, the rotary unit 90U consists of the rotary body 90 and trays 80y, 80m, 80c, and 80k.

[0025] The toner cartridges 70y to 70k are detachably held in trays 80y to 80k. Furthermore, trays 80y to 80k are supported so as to be slidable outside the rotary unit 90. The combined portion of the rotary unit 90U and the toner cartridges 70y, 70m, 70c, and 70k can be called the rotary assembly 90A. In other words, the rotary assembly 90A comprises the rotary unit 90U and the toner cartridges 70y, 70m, 70c, and 70k.

[0026] As will be described later, the rotary body 90 is rotatable around the axis of rotation (center of rotation) 90C. The axis of rotation 90C coincides with the axis of rotation of the rotary frame 90f, the rotary unit 90U, and the rotary assembly 90A. In addition, the axis of rotation 90C is substantially parallel to the axis of rotation (center of rotation) of the photosensitive drum 2.

[0027] The rotary body 90 rotates around the rotation axis 90C, allowing any of the developing rollers 51y, 51m, 51c, or 51k to face the photosensitive drum 2. The position where developing roller 51y faces the photosensitive drum 2 is called the yellow developing position. The position where developing roller 51m faces the photosensitive drum 2 is called the magenta developing position. The position where developing roller 51c faces the photosensitive drum 2 is called the cyan developing position. The position where developing roller 51k faces the photosensitive drum 2 is called the black developing position. In other words, the rotary body 90 can rotate around the rotation axis 90C so that the positions of the developing rollers 51y, 51m, 51c, and 51k relative to the photosensitive drum 2 change. The black developing position is an example of the first developing position where the first developing roller (developing roller 51k) faces the photosensitive drum 2. Another developing orientation is an example of the second developing orientation in which the second developing roller (developing rollers 51y~51c) faces the photosensitive drum 2.

[0028] As shown in Figure 2, the main body of the device 1A has motors M1, M2, and M3 as drive sources. Motor M1 supplies the driving force to rotate the rotary body 90 around the rotation axis 90C. In other words, motor M1 rotates the rotary assembly 90A and the rotary unit 90U around the rotation axis 90C.

[0029] Furthermore, the main body 1A of the device has a drive unit 98 including a motor M2 and a transmission unit. The transmission unit includes drive racks 15L and 15R as drive gears and a transmission unit 15t. The driving force of the motor M2 is transmitted to the drive racks 15L and 15R by the transmission unit 15t. In other words, the motor M2 is configured to drive the drive racks 15L and 15R, and moves the trays 80y, 80m, 80c, and 80k relative to the rotary body 90 via the drive racks 15L and 15R.

[0030] Motor M3 drives components other than those driven by motors M1 and M2. For example, motor M3 drives the photosensitive drum 2, developing units 50y, 50m, 50c, 50k, pickup roller 310, feed roller 311, transport roller pair 320, secondary transfer roller 12, belt-driven roller 10b, and fixing device 40.

[0031] The components driven by motors M1, M2, and M3 can be changed as appropriate. Furthermore, the functions of any two or all three of motors M1, M2, and M3 can be combined into a single motor. Alternatively, additional drive sources other than motors M1, M2, and M3 may be added.

[0032] Here, the subscripts y, m, c, and k attached to the developing units 50y, 50m, 50c, and 50k, the toner cartridges 70y, 70m, 70c, and 70k, and the trays 80y, 80m, 80c, and 80k indicate the toner color. The basic configuration and function of the developing units 50y, 50m, 50c, and 50k are common. The basic configuration and function of the toner cartridges 70y, 70m, 70c, and 70k are also common. Furthermore, the basic configuration and function of the trays 80y, 80m, 80c, and 80k are also common. Therefore, when there is no need to distinguish between them, the subscripts y, m, c, and k are omitted, and they are described as any one of the four units, cartridges, or trays.

[0033] As shown in Figure 3, the toner cartridge 70 has a toner frame 71. The toner frame 71 includes a toner storage section 71a for storing toner and an discharge opening 71b communicating with the toner storage section 71a.

[0034] The developing unit 50 has a developing frame (storage frame) 53. The developing frame 53 includes a developing-side storage section 53a, which serves as a developer storage section provided on the developing side, a receiving opening 53b that communicates with the developing-side storage section (toner supply chamber) 53a, and a backflow prevention member 55 that prevents toner from flowing from the developing-side storage section 53a to the toner storage section 71a. It also has a sealing member 53c for sealing the receiving opening 53b when the toner cartridge 70 is removed. As mentioned above, the developing unit 50 also includes a developing roller 51, a supply roller 52, a developing blade 54, etc.

[0035] As shown in Figure 4A, the developing roller 51k provided in the developing unit 50k is an example of a first developing roller. The developing roller 51m provided in the developing unit 50m is an example of a second developing roller. The developing frame 53k of the developing unit 50k equipped with a developing-side housing 53a is an example of a first housing frame equipped with a first housing. The developing frame 53m of the developing unit 50m equipped with a developing-side housing 53a is an example of a second housing frame equipped with a second housing. The rotary body 90 is an example of a rotatable rotary having a first developing roller, a second developing roller, a third developing roller, a fourth developing roller, a first housing frame equipped with a first housing, a second housing frame equipped with a second housing, a third housing frame equipped with a third housing, and a fourth housing frame equipped with a fourth housing.

[0036] The toner cartridge 70 is movable between an installed position and a retracted position relative to the developing frame 53. When the toner cartridge 70 is in the installed position relative to the developing frame 53, the discharge opening 71b faces the receiving opening 53b. In other words, the toner storage section 71a of the toner cartridge 70 and the developing-side storage section 53a of the developing unit 50 are in communication via the discharge opening 71b and the receiving opening 53b. When toner is supplied from the toner cartridge 70 to the developing unit 50, at least a portion of the receiving opening 53b is located below at least a portion of the discharge opening 71b.

[0037] Then, the toner stored in the toner storage section 71a is discharged from the discharge opening 71b, and the toner discharged from the discharge opening 71b is stored in the developer-side storage section 53a through the receiving opening 53b. The toner stored in the developer-side storage section 53a is supplied to the developer roller 51. Through this path, the toner stored in the toner storage section 71a is supplied to the developer roller 51.

[0038] It is desirable that the toner cartridge 70 has a sealing member (first sealing member) not shown that covers the discharge opening 71b. It is also desirable that the developing unit 50 has a sealing member (second sealing member) not shown that covers the receiving opening 53b.

[0039] When the toner cartridge 70 is not installed in the developing unit 50, it is desirable that the discharge opening 71b and the receiving opening 53b be covered with sealing members so as toner outflow from the discharge opening 71b and the receiving opening 53b.

[0040] (Image formation process) The image forming operation in this embodiment will now be described. First, the photosensitive drum 2 is rotated in the direction of arrow R1 (counterclockwise) in Figure 1, in synchronization with the rotation of the intermediate transfer belt 10a. Then, the surface of the photosensitive drum 2 is uniformly charged by the charging roller 3.

[0041] When forming a color image on sheet S, the rotary body 90 rotates in the direction of arrow R2 (clockwise) in Figure 1, supporting the developing units 50y, 50m, 50c, and 50k, as shown below. The electrophotographic process is then repeated, moving the developing rollers 51y, 51m, 51c, and 51k one by one to the developing position.

[0042] First, the scanner 4 irradiates the photosensitive drum 2 with laser light based on image data corresponding to the yellow image, forming an electrostatic latent image corresponding to the yellow image on the surface of the photosensitive drum 2. In parallel with the formation of this electrostatic latent image, the motor M1 rotates the rotary body 90, causing the rotary body 90 to assume the yellow developing position. When the rotary body 90 is in the yellow developing position, the developing roller 51y is in the developing position and develops the electrostatic latent image formed on the photosensitive drum 2 with yellow toner.

[0043] In this embodiment, each of the developing rollers 51y, 51m, 51c, and 51k is an elastic roller with rubber covering a metal shaft. In the developing position, each of the developing rollers 51y, 51m, 51c, and 51k is in contact with the photosensitive drum 2 to develop the electrostatic latent image. In other words, the image forming apparatus 1 in this embodiment employs a contact developing method. However, in the developing position, each of the developing rollers 51y, 51m, 51c, and 51k may develop the electrostatic latent image with a gap between them and the photosensitive drum 2. In other words, the image forming apparatus 1 may employ a non-contact developing method. Details of the developing unit will be described later. When in the developing position, the rotary body 90 is in a first position.

[0044] When the yellow toner image is developed, the primary transfer belt located inside the intermediate transfer belt 10a The yellow toner image on the photosensitive drum 2 is first transferred to the intermediate transfer belt 10a by the photo roller 11.

[0045] From this point onward, the rotary unit 90 is rotated to move the developing rollers 51m, 51c, and 51k sequentially to the developing position, thereby forming toner images of each color. Specifically, after a yellow toner image is formed on the intermediate transfer belt 10a, the rotary unit 90 assumes the magenta developing position, and a magenta toner image is formed on the intermediate transfer belt 10a. After a magenta toner image is formed on the intermediate transfer belt 10a, the rotary unit 90 assumes the cyan developing position, and a cyan toner image is formed on the intermediate transfer belt 10a. After a cyan toner image is formed on the intermediate transfer belt 10a, the rotary unit 90 assumes the black developing position, and a black toner image is formed on the intermediate transfer belt 10a.

[0046] Then, the primary transfer is repeated on the intermediate transfer belt 10a so that the four toner images are superimposed, thereby forming a color image on the intermediate transfer belt 10a.

[0047] Meanwhile, the sheets S are fed from a sheet storage section 300 located at the bottom of the main body 1A of the device by a pickup roller 310. The sheets S are separated one by one by a feed roller 311 and a separation roller 312 and then sent to a transport roller pair 320. The transport roller pair 320 sends the fed sheets S to the transfer section (secondary transfer section), which is the nip of the intermediate transfer belt 10a and the secondary transfer roller 12. The color image on the intermediate transfer belt 10a is transferred (secondary transfer) to the surface of the transported sheets S.

[0048] The sheet S onto which the color image has been transferred is sent to the fixing device 40. In the fixing device 40, the sheet S is heated and pressurized, and the image is fixed to the sheet S. After passing through the fixing device 40, the sheet S is discharged outside the image forming apparatus 1 as a finished product.

[0049] On the other hand, when forming a monochrome image on the sheet S, the rotary unit 90 assumes a black developing position. In this state, an electrostatic latent image is formed on the surface of the photosensitive drum 2 by charging and exposure of the photosensitive drum 2, and then the electrostatic latent image is developed with black toner by the developing roller 51k located in the developing position. The black toner image is first transferred to the intermediate transfer belt 10a, and then secondarily transferred to the sheet S. The subsequent steps are the same as for color images.

[0050] (Rotary configuration) The configuration of the rotary body 90 will be explained using Figures 1, 4A, 4B, and 5. Figures 4A and 4B are cross-sectional views showing the rotary body 90 and its surroundings of the image forming apparatus 1. Note that Figures 4A and 4B are cross-sectional views obtained by cutting the apparatus with a virtual plane perpendicular to the rotation axis 90C of the rotary body 90. Figure 5 is a perspective view of the rotary body 90.

[0051] As mentioned above, the toner cartridges 70y to 70k are detachable from the rotary body 90. When the toner in the toner cartridges 70y to 70k runs out, the user can replenish the toner in the image forming apparatus 1 by replacing the toner cartridges 70y to 70k.

[0052] As shown in Figure 1, the apparatus body 1A has a frame 16 that houses the rotary body 90. The frame 16 is the main frame of the image forming apparatus 1 in this embodiment. The frame 16 is the housing (structure) of the apparatus body 1A, which is composed of a frame and exterior members, and in this embodiment it is in the shape of a roughly rectangular parallelepiped.

[0053] The frame 16 has an opening 16a. More specifically, the frame 16 has a side surface 16b that extends in a direction intersecting the horizontal direction. The side surface 16b is the +X side of the device body 1A. It constitutes at least a part of the surface. The opening 16a is located on this side surface 16b. Side surface 16b is the side surface located downstream of the discharge port in the discharge direction from which the image-formed sheet S is discharged from the discharge port of the apparatus body 1A. From the side surface 16b of the image forming apparatus 1, the user can access the sheet storage section 300 to replenish the sheet S or retrieve the sheet S discharged from the discharge port. Therefore, side surface 16b can be said to be the front (front) of the apparatus body 1A.

[0054] Toner cartridges 70y, 70m, 70c, and 70k are detachable from the rotary body 90 through the opening 16a. In other words, toner cartridge 70k is an example of a first toner cartridge that contains toner supplied to the first developing roller (developing roller 51k) and is detachable from the rotary (rotary body 90) through the opening 16a of the frame 16 of the device body 1A. Toner cartridge 70m is an example of a second toner cartridge that contains toner supplied to the second developing roller (developing roller 51m) and is detachable from the rotary (rotary body 90) through the opening 16a of the frame 16 of the device body 1A.

[0055] In this embodiment, the toner cartridges 70y, 70m, 70c, and 70k are supported by trays 80y, 80m, 80c, and 80k, and are attached to and detached from the rotary body 90 through the opening 16a. In other words, the user can attach and detach the toner cartridges 70y to 70k to the rotary body 90 via trays 80y to 80k.

[0056] The opening 16a is located on the side surface 16b of the frame 16, which is substantially parallel to the rotation axis 90C of the rotary body 90. Therefore, when the toner cartridge 70 is replaced, the toner cartridge 70 passes through the opening 16a in a direction that intersects (preferably perpendicular to) the rotation axis 90C.

[0057] The image forming apparatus 1 has a door 14 that covers the opening 16a of the frame 16. The door 14 is an opening / closing member that can move between a closed position that covers the opening 16a and an open position that exposes the opening 16a.

[0058] As described above, in this embodiment, the toner cartridge 70 is configured to be detachable from the rotary body 90 via the tray 80. Therefore, the toner cartridge 70 can be stably attached to and detached from the rotary body 90.

[0059] More specifically, the user can replace the toner cartridge 70 by attaching and detaching the toner cartridge 70 to a tray 80 that is configured to be movable relative to the rotary body 90 (i.e., relative to the device body 1A). In comparison, in a configuration where the user replaces the toner cartridge by directly inserting and removing it from the device body, the user is required to insert the toner cartridge to a predetermined mounting position (attachment / detachment position) inside the device body. In this embodiment, the tray 80 is movable so that the toner cartridge 70 moves to the mounting position while supporting the toner cartridge 70. That is, the tray 80 is movable in and out of the device body. Therefore, the user can replace the toner cartridge 70 with a simple operation of placing the toner cartridge 70 on the tray 80, improving operability. At this time, the rotary body 90 is in a second position.

[0060] Furthermore, the toner cartridge 70 has a long, slender shape with its longitudinal direction being the Y-direction, which is parallel to the rotation axis 90C of the rotary body 90. In other words, the longitudinal dimension of the toner cartridge 70 is greater than the height and width of the cross-section perpendicular to the longitudinal direction. When handling such a long, slender toner cartridge 70, an opening 16a is placed on the side surface 16b of the frame 16, which is approximately parallel to the longitudinal direction (Y-direction) of the toner cartridge 70, allowing the toner cartridge to be opened. The 70 can pass through the opening 16a with a short travel distance. For example, this makes it easier to replace the toner cartridge 70 compared to inserting or removing the toner cartridge 70 through an opening provided on either side (+Y side or -Y side) of the frame 16 in the longitudinal direction of the toner cartridge 70.

[0061] The rotary body 90 can rotate around the rotation axis 90C to assume a replacement position that allows the removal of any of the toner cartridges 70y to 70k from the rotary body 90. The position in which the removal of toner cartridge 70y is permitted is called the yellow replacement position. The position in which the removal of toner cartridge 70m is permitted is called the magenta replacement position. The position in which the removal of toner cartridge 70c is permitted is called the cyan replacement position. The position in which the removal of toner cartridge 70k is permitted is called the black replacement position. The black replacement position is an example of the first replacement position in which the removal of the first toner cartridge from the rotary is permitted. The yellow / magenta / cyan replacement positions are examples of the second replacement positions in which the removal of the second toner cartridge from the rotary is permitted.

[0062] Figure 4A shows a cross-section of the rotary body 90 in the developing position (specifically, the yellow developing position). Figure 4B shows a cross-section of the rotary body 90 in the replacement position (specifically, the black replacement position).

[0063] As shown in Figures 4A and 4B, four trays 80y to 80k are attached to the rotary body 90. Each tray 80y to 80k holds a toner cartridge 70y to 70k. In Figures 4A and 4B, the trays 80y to 80k are housed inside the rotary body 90, and this state can be said to be the state in which the toner cartridges 70y to 70k are mounted on the developing units 50y, 50m, 50c, and 50k.

[0064] As described above, the toner cartridge 70 is movable between an installed position and a retracted position relative to the developing frame 53 of the developing unit 50. In other words, the first toner cartridge (toner cartridge 70k) is movable between a first installed position and a first retracted position relative to the first housing frame (developing frame 53k). The second toner cartridge (toner cartridge 70m) is movable between a second installed position and a second retracted position relative to the second housing frame (developing frame 53m).

[0065] When the toner cartridge 70 is in the mounting position relative to the developing frame 53, the discharge opening 71b and the receiving opening 53b face each other, as shown in Figure 3. In this state, the toner cartridge 70 is configured to supply toner to the developing side storage section 53a through the receiving opening 53b (the opening of the storage frame).

[0066] Trays 80y to 80k are configured to move the toner cartridge 70 relative to the rotary body 90 (more specifically, relative to the developing frame 53 of the developing unit 50). In other words, trays 80y to 80k are configured to move the toner cartridge 70 between the mounting position and the retracted position.

[0067] Here, the rotational drive of the rotary body 90 will be explained using Figure 5. As shown in Figure 5, disc gears 92L and 92R are formed at both ends of the rotary body 90. Rotary drive gears 93L and 93R are connected to both ends of the oscillating shaft 91 in a way that allows for power transmission. Here, the driving force of the motor M1 is transmitted to the rotary drive gear 93R by the power transmission mechanism. Next, the driving force is transmitted from the rotary drive gears 93L and 93R to the disc gears 92L and 92R, thereby driving the rotary body 90 to rotation.

[0068] Furthermore, the rotary body 90 is supported so as to be able to swing around the pivot shaft 91. The rotary body 90 is biased by a biasing member (not shown) in a counterclockwise direction around the pivot axis 91, as shown in Figures 4A and 4B. This direction can be described as the direction in which each of the developing rollers 51y to 51k approaches the photosensitive drum 2. As a result, when the rotary body 90 is in the developing position, each of the developing rollers 51y to 51k is in contact with the photosensitive drum 2.

[0069] On the other hand, as shown in Figure 5, rotary cams 90eL and 90eR are provided at both ends of the rotary body 90. When the rotary body 90 rotates clockwise around the rotation axis 90C in Figures 4A and 4B, the rotary cams 90eL and 90eR come into contact with the rollers 96 (Figures 4A and 4B) supported by the frame 16. Then, they move clockwise around the pivot axis 91 in Figures 4A and 4B. This direction can be described as the direction in which each of the developing rollers 51y to 51k moves away from the photosensitive drum 2. This direction can also be described as the direction in which the rotary body 90 moves closer to the opening 16a and door 14 of the frame 16.

[0070] As a result, when the rotary body 90 rotates and switches from the developing position to the replacement position, the rotary body 90 oscillates around the pivot axis 91. When the rotary body 90 is in the replacement position, the developing roller 51 is separated from the photosensitive drum 2.

[0071] As shown in Figure 4B, in the black cartridge replacement position, the toner cartridge 70k stops in a position facing the opening 16a and door 14 provided on the side 16b of the main body 1A of the device. From this position, when the tray 80k is slid from the mounting position on the developing unit 50k to the outside of the rotary body 90, the user can replace the toner cartridge 70k.

[0072] (Developing unit configuration) Next, the details of the developing unit 50 according to this embodiment will be described using Figure 6. Figure 6 is a schematic diagram showing an example of the developing unit 50 of this embodiment.

[0073] The developing unit 50 of this embodiment includes a developing frame 53 as the frame of the developing unit 50, a developing roller 51, a supply roller 52, a developing blade 54, and a backflow prevention member 55.

[0074] The developing roller 51 has a multilayer structure in which a conductive elastic layer, consisting of a base layer and a surface layer, is provided around a 6 mm core made of a metal such as aluminum, its alloy, or stainless steel, with an outer diameter of 10 mm. The base layer of the elastic layer is made of rubber such as butadiene acrylonitrile rubber (NBR), ethylene-propylene-diene polyethylene (EPDM), silicone rubber, or urethane rubber, and the surface layer is made of ether urethane or nylon. Of course, it is not limited to these, and a structure in which a foam such as sponge is used as the base layer and a rubber elastic layer is formed as the surface layer can also be used. Alternatively, a single-layer structure consisting only of a rubber elastic layer such as NBR, EPDM, or urethane rubber may be used.

[0075] When the developing unit 50 is in the developing position, the developing roller 51 is driven by the motor M3 and rotated in the direction of arrow R3 in Figure 6, while contacting the photosensitive drum 2 at the developing section a. At this time, the angle ra between the developing section a and the center of the developing roller 51 is 285 degrees in the direction of arrow R3, with the apex of the developing roller 51 in the +z direction being 0 degrees. The developing roller 51 has penetration amount regulating rollers (not shown) at both ends in its longitudinal direction (axial direction), and by bringing these rollers into contact with the photosensitive drum 2, the amount of penetration between the developing roller 51 and the surface of the photosensitive drum 2 is set to a predetermined value.

[0076] Below the developing roller 51, a developing blade 54, which is a toner regulating member, is supported by a pressing plate 541, and is configured such that the vicinity of the tip on the free end side abuts against the outer circumferential surface of the developing roller 51. Here, the part of the developing roller 51 that the developing blade 54 contacts (contact portion) is referred to as the regulating portion b. At the regulating portion b, the developing blade 54 regulates the thickness of the toner on the developing roller 51 and also imparts an electric charge to the toner through friction. The contact direction of the developing blade 54 is the so-called counter direction, where the tip side of the developing blade 54 is located upstream of the developing roller 51 in the rotational direction relative to the contact portion.

[0077] The developing blade 54 is a thin metal sheet with spring elasticity, such as a stainless steel sheet or a phosphor bronze sheet, which is in contact with the surface of the developing roller 51 at a predetermined linear pressure. A blade bias is applied to the press plate 541, which is a support member of the developing blade 54, by a voltage application means (not shown) so that there is a predetermined potential difference between it and the developing roller 51. When the toner is a negatively charged toner, the developing blade is set to be higher on the negative polarity side relative to the developing roller.

[0078] In this embodiment, the developing blade 54 uses a 0.1 mm thick stainless steel sheet with spring elasticity, and -200V is applied to the potential of the developing roller 51 as a blade bias. Alternatively, the developing blade 54 may be constructed by bonding or injection molding a polyamide elastomer, which is an elastic member, to the tip of a metal sheet with spring elasticity, and the elastic member side contacts the surface of the developing roller 51 with a predetermined linear pressure. In this case, the metal sheet maintains the pressure of the developing blade 54 against the developing roller 51, and if the toner is, for example, a negatively charged toner, the polyamide elastomer imparts chargeability to the toner. The metal sheet is not particularly limited as long as it maintains the pressure of the developing blade 54, and the elastic member can also be selected considering the chargeability of the toner. Furthermore, to impart further chargeability, the elastic member can be made conductive and used in combination with the blade bias.

[0079] A backflow prevention member 55 is formed near the receiving opening 53b of the developing unit 50. The backflow prevention member 55 has a long sheet portion 55a extending in the x-axis direction of the receiving opening 53b and a weight portion 55b formed on a part of the sheet portion 55a, with a part of the sheet portion fixed to the developing container of the developing unit 50. The sheet portion 55a is a thin film sheet made of resin such as PET (polyethylene terephthalate) or polyimide, or rubber such as urethane rubber. The weight portion stabilizes the behavior of the sheet portion and has the effect of directing the tip of the backflow prevention member 55 toward region C in the developing position. In addition, one end of the sheet portion is fixed to the developing frame 53 by double-sided tape or welding. In this embodiment, the backflow prevention member 55 uses a PET resin sheet with a thickness of 100 μm as the sheet member, and when the developing unit 50 is in the developing position, its end is fixed to the developing frame 53 on the +Z direction side with respect to the receiving opening 53b by double-sided tape.

[0080] In this embodiment, a toner with a particle size of 6 μm and a normal charge polarity of negative polarity is used. As an example, the toner used in this embodiment is a polymerized toner produced by polymerization. Furthermore, the toner in this embodiment does not contain magnetic components, and is a so-called non-magnetic one-component developer, where the toner is supported on the developing roller 51 mainly by intermolecular forces and electrostatic forces (mirror image forces). However, a one-component developer containing magnetic components may also be used. In addition, the one-component developer may contain additives (e.g., wax or silica microparticles) to adjust the toner's fluidity and charging performance. Alternatively, a two-component developer composed of a non-magnetic toner and a magnetic carrier may be used. When a magnetic developer is used, a cylindrical developing sleeve with a magnet placed inside may be used as the developer carrier.

[0081] The toner supported on the developing roller 51 is restricted to the desired toner thickness by the contact pressure of the developing blade 54. When developing onto the photosensitive drum 2 in the developing unit a, the peripheral speed of the developing roller 51 is set to a different speed from the peripheral speed of the photosensitive drum 2 in order to obtain the appropriate image density. This is possible. The peripheral speed ratio is preferably in the range of 0.5 to 3.0 times the peripheral speed of the developing roller 51 relative to the peripheral speed of the photosensitive drum 2. In this embodiment, the peripheral speed ratio was set to 1.5 times.

[0082] The supply roller 52 contacts the developing roller 51 at the supply section c, supplying toner to the developing roller 51 and simultaneously peeling off and recovering any undeveloped toner (remaining toner) from the developing roller 51. The supply roller 52 is preferably a sponge structure using a foamed elastic material or a fur brush structure with rayon, nylon, or other fibers implanted on a metal core, from the standpoint of supplying toner to the developing roller 51 and peeling off the remaining toner. Furthermore, the sponge structure using a foamed elastic material can be either closed-cell foam with independent internal cells or continuous-cell foam with interconnected internal cells, but the continuous-cell foam is more preferable because it can store a larger amount of toner internally, thus enabling a more stable toner supply. In this embodiment, a foam roller is used in which a continuously foamed polyurethane foam has interconnected cells with diameters of 10 to 800 μm as a foamed elastic material, on a 5 mm metal core, with an elastic material having conductivity by dispersing carbon or the like, provided to a diameter of 11 mm.

[0083] The supply roller 52, which is made of foam roller, contacts the developing roller 51 and rotates in the counter direction relative to the developing roller 51, i.e., in the direction of arrow R4. In this embodiment, the surface speed of the supply roller 52 rotates at a speed that is 75% of the surface speed of the developing roller 51. Here, it is preferable that the supply roller 52 contacts the developing roller 51 with an intrusion amount in the range of 0.1 to 1.5 mm, from the viewpoint of supplying toner to the developing roller 51 and removing residual toner. In this embodiment, the intrusion amount of the supply roller 52 into the developing roller 51 is 1.0 mm. In addition, a supply roller bias is applied to the core metal of the supply roller 52 by a voltage application means (not shown) so as to create a predetermined potential difference with the developing roller 51. In this embodiment, -200V is applied relative to the potential of the developing roller 51 so as to supply negatively charged toner.

[0084] (Toner supply configuration) Next, the toner supply path to the developing roller 51 according to this embodiment will be explained using Figure 7. Figure 7 is a schematic cross-sectional view of the area near the receiving opening 53b when the developing unit 50 is in the developing position, and arrow D indicates the movement of toner from the toner cartridge 70. In Figure 7, L1 is the common tangent line between the developing roller 51 and the supply roller 52 on the receiving opening 53b side, and the contact points between L1 and the developing roller 51 and the supply roller 52 are indicated as P51 and P52, respectively. The area enclosed by P51, P52 and the supply section c is designated as area C and is shown with diagonal lines.

[0085] As described above, when the toner cartridge 70 is in the mounting position relative to the developing frame 53, the discharge opening 71b faces the receiving opening 53b. In other words, the toner storage section 71a of the toner cartridge 70 and the developing-side storage section 53a of the developing unit 50 are in communication via the discharge opening 71b and the receiving opening 53b. The toner stored in the toner storage section 71a is discharged from the discharge opening 71b, and the toner discharged from the discharge opening 71b is stored in the developing-side storage section 53a through the receiving opening 53b. Here, the receiving opening 53b may be located along the entire length (Y-axis direction) of the developing frame 53, or it may be located only in a part of it. In this embodiment, the receiving opening 53b is located at two locations near both ends of the length of the developing frame 53.

[0086] The toner stored in the developing-side storage section 53a is supplied to the developing roller 51 by the supply roller 52. In this embodiment, the supply roller 52 contacts the developing roller 51 with a predetermined amount of penetration in the supply section c, so the cells of the supply roller 52 are in a crushed state when in contact with the supply section. As the supply roller 52 rotates in the direction of arrow R4, the crushed cell is released downstream of the supply unit c in the direction of arrow R4, drawing in the toner from area C, and simultaneously stripping and recovering the toner on the developing roller 51 at the cell wall. Furthermore, as the cell is crushed upstream of the supply unit c in the direction of arrow R4, the toner inside the cell is discharged and supplied to the developing roller 51. At this time, the toner near the upstream side of the supply unit c in the direction of arrow R4 is pushed out by the toner discharged from the supply roller 52 and moves in the direction of arrow A through the gap between the supply roller 52 and the developing container. The toner that has moved in the direction of arrow A mixes with other toner in area C within the developing side storage unit 53a and is then drawn back into the cell of the supply roller 52 at the supply unit c.

[0087] In this manner, the toner stored in the developing-side storage section 53a is supplied to the developing roller 51 by the supply roller 52 while circulating in the direction of arrow A.

[0088] (Operation of backflow prevention member 55) The operation of the backflow prevention member 55 as a suppression member will be explained using Figure 8. Figure 8 is a cross-sectional view of the rotary body 90, showing the phases of the developing unit 50 divided into states TP1 to TP4.

[0089] While the rotary rotates from TP1 to TP2, the backflow prevention member 55 blocks the receiving opening 53b due to the weight of its weight portion 55b. In other words, the backflow prevention member 55 is in a restraining position that covers the receiving opening 53b, thereby suppressing the movement of toner.

[0090] As the rotary rotates from TP2 to TP3, the backflow prevention member 55 hangs down in the -Z direction due to the weight of its weight portion 55b, opening the receiving opening 53b. As a result, the toner contained in the toner storage section 71a is received in the developing-side storage section 53a through the discharge opening 71b and the receiving opening 53b. Arrow E indicates the movement of the toner at that time. In other words, the backflow prevention member 55 is movable from the suppression position to a retracted position, and in the retracted position, it does not cover the receiving opening 53b, allowing the toner to move.

[0091] As the rotary rotates from TP3 to TP4, the developing unit 50 approaches the phase of TP4, and the backflow prevention member 55 closes the receiving opening 53b due to the weight of the weight portion 55b.

[0092] While the rotary rotates from TP4 to TP1, the backflow prevention member 55 blocks the receiving opening 53b due to the weight of its weight portion 55b.

[0093] As a result of the above operation, the backflow prevention member 55 closes the receiving opening 53b while rotating from TP4 to TP2, preventing toner in the developer-side storage section 53a from flowing back into the toner storage section 71a. Therefore, backflow of toner from the developer-side storage section 53a to the toner storage section 71a is suppressed during the phase from TP4 to TP2, including the toner cartridge replacement position TP1.

[0094] (Overlap and countermeasure configuration) Incidentally, the toner carried on the developing roller 51 is subjected to mechanical stress by rubbing against the developing blade 54, the photosensitive drum 2, and the supply roller 52, which can cause phenomena such as the removal of external additives from the surface of the toner particles or the deformation of the toner particles. As the number of printed pages increases and these phenomena become more pronounced, the toner becomes less likely to be charged to its normal charging polarity even when rubbed against the developing blade 54. Such toner is called "degraded toner." In contrast to degraded toner, the toner stored in the developing side storage section 53a, which is in a state where it is easily charged to its normal charging polarity, is called "normal toner."

[0095] When the proportion of degraded toner to normal toner increases among the toner carried on the developing roller 51, a state of insufficient toner charge occurs. Insufficient toner charge means that among the toner particles carried on the developing roller 51 and rubbed against the developing blade 54, there are a relatively large number of particles with a charge close to zero or with a charge opposite to the normal charge polarity. In such a state of insufficient toner charge, toner adheres to areas on the surface of the photosensitive drum 2 where an electrostatic latent image has not been formed, is transferred from the photosensitive drum 2 to the intermediate transfer belt, and then to the recording material, resulting in a thin toner image adhering to areas of the recording material where an image should not be formed. This type of image defect is called "fogging."

[0096] Furthermore, in a configuration where the toner cartridge 70 is replaced, the toner stored in the toner storage section 71a of the toner cartridge 70 and newly supplied to the developer storage section 53a is called "new toner" or "fresh toner." In a configuration where the toner cartridge 70 is replaced, supplying new toner to the developer storage section 53a can reduce the proportion of deteriorated toner in the developer storage section. However, if a certain amount of deteriorated toner accumulates in the developer storage section 53a, it becomes difficult to completely suppress fogging even if new toner is supplied. Therefore, it is preferable to discharge the deteriorated toner from the developer storage section 53a in order to suppress fogging.

[0097] (Refresh operation) In this embodiment, when deteriorated toner has accumulated in the developing-side storage section 53a, the deteriorated toner in the developing-side storage section 53a can be stored in the refresh cartridge 72 by installing the refresh cartridge 72 as a storage cartridge. The stored deteriorated toner can then be discharged from the main unit along with the refresh cartridge 72. This reduces the proportion of deteriorated toner in the developing-side storage section 53a and suppresses fogging. A detailed explanation follows below.

[0098] (Refresh cartridge configuration) In this embodiment, the refresh operation is performed using a refresh cartridge 72. The refresh cartridge 72 is a separate container specifically for refreshing, distinct from the toner cartridge 70, and has the same external shape as the toner cartridge 70. Like the toner cartridge 70, the refresh cartridge 72 is configured to be detachably attached to the rotary body 90 via a tray 80. That is, the tray 80 functions not only as a support for the toner cartridge 70 as a developer cartridge, but also as a cartridge support for the refresh cartridge 72 as a storage cartridge. When the refresh cartridge 72 is removed from the rotary body 90 and the developing unit 50, the rotary body 90 is in the replacement position.

[0099] The configuration of the refresh cartridge 72 will be explained using Figure 9. The refresh cartridge 72 has a toner frame 73. The toner frame 73 has a deteriorated toner storage section 73a for storing deteriorated toner, a return opening 73b which is a storage opening communicating with the deteriorated toner storage section 73a, and a cartridge sealing member 73c which is a storage opening sealing member that covers and seals the return opening 73b. It also has a release projection 73h for moving the sealing member 53c of the developing unit 50 when it is mounted on the rotary body 90. Inside the deteriorated toner storage section 73a, there is a moving member 74 which moves the backflow prevention member 55 inside the developing side storage section 53a, and a connecting member 73d which suspends and connects the cartridge sealing member 73c and the moving member 74 from support members 73e, 73f, and 73g.

[0100] (Operation of the movable member 74) The operation of the moving member 74 will be explained using Figures 10A and 10B. Figure 10A shows the state before the refresh cartridge 72 is attached to the developing unit 50.

[0101] The movable member 74 consists of a spring 74a and a pressing member 74b. The spring 74a is fixed to the inner surface of the deteriorated toner storage section 73a facing the return opening 73b, and pressurizes the pressing member 74b toward the return opening 73b.

[0102] When the refresh cartridge 72 is not mounted on the developing unit 50, the cartridge sealing member 73c covers the return opening 73b. The cartridge sealing member 73c is slidable in the +X direction, and sliding it exposes the return opening 73b.

[0103] The connecting member 73d is suspended and connected to the cartridge sealing member 73c and the push member 74b by the support members 73e, 73f, and 73g. When the cartridge sealing member 73c covers the return opening 73b, the connecting member 73d pulls the push member 74b in the opposite direction to the spring 74a's pushing direction, thereby housing the movable member 74 within the deteriorated toner storage section 73a. In the same state, the receiving opening 53b of the developing unit 50 is sealed by the sealing member 53c.

[0104] The sealing member 53c of the developing unit 50 is slidable in the -X direction, and sliding it opens the receiving opening 53b. The developing frame 53 is equipped with a release projection 53d for moving the cartridge sealing member 73c when the refresh cartridge 72 is mounted on the rotary body 90.

[0105] The refresh cartridge 72 is movable relative to the developing frame 53 between a retracted position (Figure 10A) and the mounted position (Figure 10B).

[0106] As the refresh cartridge 72 moves to the mounting position, the release projection 73h on the refresh cartridge 72 side contacts the sealing member 53c on the developing unit 50 side, pushing in the sealing member 53c. As a result, the sealing member 53c slides as it is pushed in the -X direction by the release projection 73h, opening the receiving opening 53b.

[0107] Simultaneously, the release projection 53d on the developing unit 50 side contacts the cartridge sealing member 73c on the refresh cartridge 72 side and pushes it in the +X direction. This causes the cartridge sealing member 73c to slide, and the return opening 73b opens. In this way, the cartridge sealing member 73c is movable between a housing opening sealing position that covers the return opening 73b as a housing opening and a housing opening open position in which the return opening 73b is exposed.

[0108] When the refresh cartridge 72 is in the mounting position relative to the developing frame 53, the return opening 73b faces the receiving opening 53b. In other words, the deteriorated toner storage section 72a of the refresh cartridge 72 and the developing-side storage section 53a of the developing unit 50 are in communication via the return opening 73b and the receiving opening 53b.

[0109] Figure 10B shows the refresh cartridge 72 and the developing unit 50 when installed in the developing unit 50.

[0110] When the refresh cartridge 72 is mounted on the rotary body, the connecting member 73d moves by the amount that the cartridge sealing member 73c slides in the +X direction. As a result, the push member 74b is pushed in the +Z direction through the return opening 73b by the pushing force of the spring 74a.

[0111] As a result, the pushing member 74b moves in the +Z direction, pushing up the backflow prevention member 55. Consequently, the deteriorated toner storage section 73a of the refresh cartridge 72 and the developing unit The developing side housing section 53a of 50 is in communication with the return opening 73b and the receiving opening 53b.

[0112] When the backflow prevention member 55 is pushed up, the receiving opening 53b is opened, and the deteriorated toner accumulated in the developing side storage section 53a is discharged from the receiving opening 53b, and the deteriorated toner discharged from the receiving opening 53b is stored in the deteriorated toner storage section 73a through the return opening 73b. Arrow F indicates the movement of the deteriorated toner at that time. In this way, when the refresh cartridge 72 as a storage cartridge is installed, the moving member 74 as a suppression prevention mechanism can retract the backflow prevention member 55 as a suppression member from the suppression position. The rotary body 90 may rotate with the refresh cartridge 72 installed. In this case, the rotary body 90 can rotate one or more times.

[0113] After the refresh cartridge 72 has finished discharging the degraded toner from the developing-side storage section 53a, it moves from the mounting position to the retracted position in the same manner as the toner cartridge 70. During retraction, the cartridge sealing member 73c slides in the -X direction, covering the return opening 73b. As the sealing member 72c slides in the -X direction, the connecting member 73d moves, and the connecting member 73d pulls the push member 74b in the opposite direction to the push direction of the spring 74a, thereby re-storing the push member 74b into the degraded toner storage section 73a. When the refresh cartridge 72 is removed from the rotary body 90 and the developing unit 50, the rotary body 90 is in the replacement position. That is, when the refresh cartridge 72 moves from the mounting position to the retracted position, the return opening 73b is located below the receiving opening 53b. Therefore, the return of the toner collected in the refresh cartridge 72 to the developing-side storage section 53a is suppressed.

[0114] As described above, in this embodiment, the amount of deteriorated toner accumulated in the developing-side storage unit 53a can be reduced by using the refresh cartridge 72 to recover the deteriorated toner. After the refresh cartridge 72 is removed and replaced with a new toner cartridge 70, new toner is supplied to the developing unit 50. As a result, the proportion of deteriorated toner in the developing-side storage unit 53a is reduced, and image defects such as fogging are suppressed.

[0115] [Example 2] In this embodiment, the main unit performs a refresh operation after the refresh cartridge is installed in order to discharge the deteriorated toner in the developing side storage section 53a using the refresh cartridge. The other configurations are the same as in Embodiment 1, so their explanation is omitted.

[0116] (Second refresh cartridge 75) In this embodiment, the refresh operation is performed using a second refresh cartridge 75. The second refresh cartridge 75 is a separate container specifically for refreshing, distinct from the toner cartridge 70. It has the same external shape as the toner cartridge 70 and, like the toner cartridge 70, is configured to be detachably attached to the rotary body 90 via a tray 80.

[0117] The configuration of the second refresh cartridge 75 will be explained using Figure 11. As shown in Figure 11, the second refresh cartridge 75 has a toner frame 76. The toner frame 76 has a deteriorated toner storage section 76a for storing deteriorated toner, an discharge opening 76b communicating with the deteriorated toner storage section 76a, and a cartridge sealing member 76c that covers and seals the discharge opening 76b.

[0118] Furthermore, when the rotary body 90 is attached, it is equipped with a release projection 76d for moving the sealing member 53c of the developing unit 50.

[0119] The deteriorated toner storage section 76a includes a moving member 77 that operates in conjunction with the cartridge sealing member 76c to move the backflow prevention member 55 in the developer-side storage section 53a, and a deteriorated toner backflow prevention section 78 that prevents deteriorated toner from flowing from the deteriorated toner storage section 76a to the developer-side storage section 53a.

[0120] The deteriorated toner backflow prevention unit 78 has a long sheet portion 78a and a weight portion 78b formed on a part of the sheet portion 78a, and a part of the sheet portion is fixed to the movable member 77.

[0121] (Operation of the movable member 77) The operation of the moving member 77 will be explained using Figures 12A and 12B. Figure 12A shows the state before the second refresh cartridge 75 is attached to the developing unit 50.

[0122] The movable member 77 consists of a spring 77a and a pressing member 77b, and operates in conjunction with the cartridge sealing member 76c. The spring 77a is fixed to the end of the pressing member 77b and is inverted to press the pressing member 77b in the +Z direction.

[0123] When the second refresh cartridge 75 is not mounted on the developing unit 50, the cartridge sealing member 76c covers the discharge opening 76b. The cartridge sealing member 76c is slidable in the +X direction, and sliding it opens the discharge opening 76b.

[0124] Similarly, in the uninstalled state, the receiving opening 53b of the developing unit 50 is sealed by the sealing member 53c. The sealing member 53c is slidable in the -X direction, and sliding it opens the receiving opening 53b.

[0125] The developing frame 53 is equipped with a release projection 53d for moving the cartridge sealing member 76c when the second refresh cartridge 75 is mounted on the rotary body 90.

[0126] The second refresh cartridge 75 is movable relative to the developing frame 53 between a retracted position (Figure 12A) and the mounted position (Figure 12B).

[0127] As the second refresh cartridge 75 moves to the mounting position, the release projection 76d contacts the sealing member 53c and pushes the sealing member 53c in. The sealing member 53c slides as it is pushed in the -X direction by the release projection 76d, opening the receiving opening 53b.

[0128] At the same time, the release projection 53d comes into contact with the cartridge sealing member 76c and is pushed in the +X direction, causing the cartridge sealing member 76c to slide and the return opening 73b to open.

[0129] Figure 12B shows the second refresh cartridge 75 and the developing unit 50 when mounted on the developing unit 50. When the second refresh cartridge 75 is mounted on the rotary body, the cartridge sealing member 76c slides in the +X direction, and the moving member 77 slides in the same direction. When the pushing member 77b slides to the position of the discharge opening 76b, it is pushed in the +Z direction through the discharge opening 76b by the pushing force of the spring 77a.

[0130] As a result, the pushing member 77b pushes up the backflow prevention member 55 in the developing-side storage section 53a. Consequently, the deteriorated toner storage section 76a of the second refresh cartridge 75 and the developing-side storage section 53a of the developing unit 50 are in communication via the discharge opening 76b and the receiving opening 53b.

[0131] The pushing member 77b is preferably a rod-shaped object that is sufficiently thin compared to the width of the discharge opening 76b and the receiving opening 53b. With this shape, even when the backflow prevention member 55 is pushed up, blocking of the discharge opening 76b and the receiving opening 53b is suppressed.

[0132] When the backflow prevention member 55 is pushed up and the receiving opening 53b is opened, the degraded toner accumulated in the developing side storage section 53a is discharged from the receiving opening 53b and stored in the degraded toner storage section 76a through the discharge opening 76b. Arrow G indicates the movement of the degraded toner at that time.

[0133] However, the openings (receiving opening 53b and discharge opening 76b) are not provided along the entire length of the second refresh cartridge 75. Therefore, deteriorated toner in the developing-side storage section 53a is not easily discharged in areas other than those where the openings are provided along the length. In this embodiment, after installing the second refresh cartridge 75, a refresh operation accompanied by rotary rotation is performed to promote the discharge of deteriorated toner remaining in the developing-side storage section 53a.

[0134] The more times the rotary is rotated, the more opportunities there are for degraded toner to be discharged from the developing-side storage section 53a, and the lower the proportion of degraded toner in the developing-side storage section 53a becomes. Approximately 10 rotary rotations are preferable for sufficient discharge of degraded toner, but the number of rotations may be determined as needed based on the size and number of openings.

[0135] By the way, in the refresh operation involving rotary rotation in this embodiment, after the second refresh cartridge 75 is installed, the backflow prevention member 55 is pushed up by the moving member 77, and the backflow prevention member 55 does not block the receiving opening 53b. Therefore, even if the deteriorated toner is collected in the deteriorated toner storage section 76a, at the supply position of the developing unit 50, there is a risk that it will return to the developing-side storage section 53a again through the discharge opening 76b from the deteriorated toner storage section 76a.

[0136] Therefore, in this embodiment, a deteriorated toner backflow prevention unit 78 is provided in the deteriorated toner storage unit 76a of the second refresh cartridge 75. This prevents the backflow of deteriorated toner from the deteriorated toner storage unit 76a to the developer-side storage unit 53a.

[0137] (Operation of the degraded toner backflow prevention unit 78) The operation of the degraded toner backflow prevention unit 78 will be explained using Figure 13. Figure 13 is a cross-sectional view of the rotary body 90, showing the phases of the developing unit 50 divided into states TP1 to TP4.

[0138] As the rotary rotates from TP1 to TP2, the deteriorated toner backflow prevention unit 78 hangs down in the -Z direction due to the weight of the weight portion 78b, and the discharge opening 76b is open.

[0139] The moving member 77 pushes up the backflow prevention member 55, and the receiving opening 53b opens, so deteriorated toner is discharged from the developing side storage section 53a to the deteriorated toner storage section 76a.

[0140] As the rotary rotates from TP2 to TP3, the deteriorated toner backflow prevention unit 78 blocks the discharge opening 76b due to the weight of the weight portion 78b. Therefore, the deteriorated toner in the deteriorated toner storage unit 76a is prevented from flowing back into the developer-side storage unit 53a.

[0141] As the rotary rotates from TP3 to TP4, and the developing unit 50 approaches the phase of TP4, the deteriorated toner backflow prevention unit 78 sags due to the weight of the weight portion 78b, opening the deteriorated toner storage unit 76a. At the same time, the deteriorated toner inside the deteriorated toner storage unit 76a The toner slides down in the -Z direction, moving away from the discharge opening 76b, thus preventing the deteriorated toner in the deteriorated toner storage section 76a from flowing back into the developer-side storage section 53a.

[0142] As the rotary rotates from TP4 to TP1, the degraded toner backflow prevention unit 78 sags again in the -Z direction due to the weight of the weight portion 78b, opening the discharge opening 76b. Therefore, in the phase from TP4 to TP2, which includes the toner cartridge replacement position TP1, the discharge opening 76b is open, and degraded toner can be discharged from the developer-side storage portion 53a to the degraded toner storage portion 76a. On the other hand, in the phase from TP2 to TP4, which includes TP3, the degraded toner backflow prevention unit 78 closes the discharge opening 76b, thereby suppressing the backflow of degraded toner from the degraded toner storage portion 76a to the developer-side storage portion 53a.

[0143] As described above, in this embodiment, the amount of deteriorated toner accumulated in the developer-side storage section 53a can be reduced by using a refresh cartridge to recover the deteriorated toner. Furthermore, by rotating the rotary motor with the refresh cartridge installed as part of the refresh operation, the recovery of deteriorated toner is promoted, further reducing the amount of deteriorated toner in the developer-side storage section 53a. In addition, a backflow prevention mechanism is in place during rotary rotation, which prevents deteriorated toner from returning to the developer-side storage section 53a. When the toner cartridge 70 is replaced with a new one, the supply of new toner reduces the proportion of deteriorated toner in the developer-side storage section 53a, thereby suppressing fogging.

[0144] Note that in Examples 1 and 2, toner cartridges 70y to 70c and 70k have different shapes. Consequently, the refresh cartridges will have different shapes for the 70y~70c and 70k models, but the only difference is the width in the depth direction; the operational details are the same for both. You can use one refresh cartridge for the 70y, 70m, and 70c models, or you can prepare multiple cartridges.

[0145] As described above, by installing a discharge container in place of the toner cartridge in the tray and performing the discharge operation, degraded toner in the developing chamber can be collected in the discharge container. This suppresses the occurrence of image defects and fogging caused by degraded toner in the developing chamber.

[0146] [Configuration 1] Image carrier and, A developing unit having a developer storage section and a receiving opening communicating with the developer storage section, configured to develop the electrostatic latent image formed on the image carrier with a developer, It has a support section on which a developer cartridge containing the developer supplied to the developer storage section through the receiving opening is removably mounted, The support portion functions as a cartridge support portion to which a cartridge containing the developer discharged from the developer storage portion through the receiving opening is removably mounted. An image forming apparatus characterized by the following: [Configuration 2] The developing unit further includes a restraining position that covers the receiving opening and a restraining member that is movable to a retracted position that is moved away from the restraining position. The storage cartridge has a suppression prevention mechanism that retracts the suppression member from the suppression position. The image forming apparatus according to configuration 1, characterized in that it is a picture forming apparatus. [Configuration 3] The aforementioned storage cartridge is When the storage cartridge is mounted on the support part, the receiving of the developing unit A receiving opening that communicates with the opening, A housing opening sealing member that is movable between a housing opening sealing position that covers the housing opening and a housing opening open position in which the housing opening is exposed, It has, The suppression prevention mechanism moves the housing opening sealing member to the housing opening open position when the housing cartridge is mounted on the support portion. The image forming apparatus according to configuration 2, characterized in that... [Structure 4] The developing unit further comprises a rotating body that supports the support portion. An image forming apparatus according to any one of configurations 1 to 3, characterized by the above. [Composition 5] The rotating body can take on a developing position in which the developing unit can develop the electrostatic latent image formed on the image carrier, and a detachable position in which the developer cartridge or the storage cartridge can be attached to or detached from the support. The image forming apparatus according to configuration 4, characterized in that... [Composition 6] The rotating body is capable of supporting the developing unit and the support portion, and is capable of assuming a first and second position, wherein when the rotating body assumes the first position, the developing position is in the developing position for developing the electrostatic latent image, and when the rotating body assumes the second position, the developer cartridge or the storage cartridge is in the attachment / detachment position. The image forming apparatus according to configuration 5, characterized by the features described herein. [Composition 7] The support portion is movable relative to the rotating body. The image forming apparatus according to configuration 5 or 6, characterized by the above. [Structure 8] The apparatus further comprises a main body that houses the image carrier, the developing unit, and the support section. The support portion is movable inside and outside the main body of the device. An image forming apparatus according to any one of configurations 1 to 3, characterized by the above. [Composition 9] A storage cartridge that is removably mounted in an image forming apparatus, the image forming apparatus comprising: an image carrier; a developer storage section; a developing unit having a receiving opening communicating with the developer storage section and configured to develop an electrostatic latent image formed on the image carrier into a developer; and a support section to which a developer cartridge containing a developer supplied to the developer storage section through the receiving opening is removably mounted. It has a storage section for storing the developer discharged from the developer storage section through the receiving opening, and is detachable from the support section. A storage cartridge characterized by the following features. [Configuration 10] The developing unit further includes a restraining position that covers the receiving opening and a restraining member that is movable to a retracted position that is moved away from the restraining position. The storage cartridge further includes a suppression prevention mechanism that retracts the suppression member from the suppression member. The storage cartridge according to configuration 9, characterized by the features described therein. [Composition 11] A receiving opening that communicates with the receiving opening of the developing unit when the receiving cartridge is mounted on the support portion, A housing opening sealing member that is movable between a housing opening sealing position that covers the housing opening and a housing opening open position that does not cover the housing opening, It further possesses, The suppression prevention mechanism moves the housing opening sealing member to the housing opening open position when the housing cartridge is mounted on the support portion. The storage cartridge according to configuration 10, characterized by the above. [Explanation of Symbols]

[0147] 1…Image forming apparatus / 50…Developing unit / 51…Developing roller / 52…Supply roller / 53…Developing frame / 53a…Developing side housing / 53b…Receiving opening / 55…Backflow prevention member / 70…Toner cartridge / 71b…Discharge opening / 72…Refresh cartridge / 74…Moving member / 90…Rotary (rotary body)

Claims

1. Image carrier and, A developing unit having a developer storage section and a receiving opening communicating with the developer storage section, configured to develop the electrostatic latent image formed on the image carrier with a developer, It has a support section on which a developer cartridge containing the developer supplied to the developer storage section through the receiving opening is removably mounted, The support portion functions as a cartridge support portion to which a cartridge containing the developer discharged from the developer storage portion through the receiving opening is removably mounted. An image forming apparatus characterized by the following features.

2. The developing unit further includes a restraining position that covers the receiving opening and a restraining member that is movable to a retracted position that is moved away from the restraining position. The storage cartridge has a suppression prevention mechanism that retracts the suppression member from the suppression position. The image forming apparatus according to feature 1.

3. The aforementioned storage cartridge is A receiving opening that communicates with the receiving opening of the developing unit when the receiving cartridge is mounted on the support portion, A housing opening sealing member that is movable between a housing opening sealing position that covers the housing opening and a housing opening open position in which the housing opening is exposed, It has, The suppression prevention mechanism moves the housing opening sealing member to the housing opening open position when the housing cartridge is mounted on the support portion. The image forming apparatus according to feature 2.

4. The developing unit further comprises a rotating body that supports the support portion. The image forming apparatus according to any one of claims 1 to 3.

5. The rotating body can take on a developing position in which the developing unit can develop the electrostatic latent image formed on the image carrier, and a detachable position in which the developer cartridge or the storage cartridge can be attached to or detached from the support. The image forming apparatus according to feature 4.

6. The rotating body is capable of supporting the developing unit and the support portion, and is capable of assuming a first and second position, wherein when the rotating body assumes the first position, the developing position is in the developing position for developing the electrostatic latent image, and when the rotating body assumes the second position, the developer cartridge or the storage cartridge is in the attachment / detachment position. The image forming apparatus according to feature 5.

7. The support portion is movable relative to the rotating body. The image forming apparatus according to feature 5.

8. The apparatus further comprises a main body that houses the image carrier, the developing unit, and the support section. The support portion is movable inside and outside the main body of the device. The image forming apparatus according to any one of claims 1 to 3.

9. A storage cartridge that is removably mounted in an image forming apparatus, the image forming apparatus comprising: an image carrier; a developer storage section; a developing unit having a receiving opening communicating with the developer storage section and configured to develop an electrostatic latent image formed on the image carrier into a developer; and a support section to which a developer cartridge containing a developer supplied to the developer storage section through the receiving opening is removably mounted. It has a storage section for storing the developer discharged from the developer storage section through the receiving opening, and is detachable from the support section. A storage cartridge characterized by the following features.

10. The developing unit further includes a restraining position that covers the receiving opening and a restraining member that is movable to a retracted position that is moved away from the restraining position. The storage cartridge further includes a suppression prevention mechanism that retracts the suppression member from the suppression member. The storage cartridge according to feature 9.

11. A receiving opening that communicates with the receiving opening of the developing unit when the receiving cartridge is mounted on the support portion, A housing opening sealing member that is movable between a housing opening sealing position that covers the housing opening and a housing opening open position that does not cover the housing opening, It further possesses, The suppression prevention mechanism moves the housing opening sealing member to the housing opening open position when the housing cartridge is mounted on the support portion. The storage cartridge according to feature 10.

Images