Image forming apparatus

Abstract

To provide an image forming apparatus in a new form developed from a conventional technique.SOLUTION: An image forming apparatus has: (i) a developing unit that has a developing frame body including a developing opening, and a toner regulation part movable to a cover position where it covers the developing opening and a retreated position where it is retreated from the cover position; (ii) a rotary that supports the developing unit; and (iii) a toner cartridge that is removably attached to the rotary, and that has a frame body including a discharge port. When the rotary is in a first posture, the developing opening is located above the discharge port, and the toner regulation part is located at the cover position. When the rotary is in a second posture, the developing opening is located below the discharge port, and the toner regulation part is located at the retreated position.SELECTED DRAWING: Figure 14

Description

Technical Field

[0001] The present invention relates to an image forming apparatus that forms an image on a recording material.

Background Art

[0002] In an electrophotographic image forming apparatus, a rotary developing method is known in which a rotary member having a plurality of developing rollers is rotated to form a color image. Patent Documents 1 and 2 describe an image forming apparatus including a rotary member having a plurality of developing rollers and a plurality of toner cartridges (toner storage containers) that are each detachable from the rotary member.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a new form of image forming apparatus that develops conventional technology.

Means for Solving the Problems

[0005] One aspect of the present invention is as follows.

[0006] A developing unit having a developing roller, a developing frame body having a receiving side accommodation chamber and a developing opening communicating with the receiving side accommodation chamber, a cover position covering the developing opening, and a toner regulating unit movable between the cover position and a retracted position retracted from the cover position; A rotary member that supports the developing unit and is rotatable around a rotation axis extending in the axial direction; A toner cartridge detachable from the rotary, (i) A supply-side storage chamber for storing toner, and (ii) a frame body including a discharge port communicating with the supply-side storage chamber, A toner cartridge having Having When the rotary is in the first posture, the developing opening is positioned above the discharge port, and the toner regulating portion is positioned at the cover position. When the rotary is in the second posture, the developing opening is positioned below the discharge port, the toner regulating portion is positioned at the retracted position, and toner discharged from the discharge port is allowed to enter the receiving-side storage chamber. An image forming apparatus characterized by the above.

[0007] One aspect of the present invention is as follows.

[0008] A developing unit having a developing roller, a developing frame body having a receiving-side storage chamber and a developing opening communicating with the receiving-side storage chamber, a cover position covering the developing opening, and a toner regulating portion movable between the cover position and a retracted position retracted from the cover position. A rotary that supports the developing unit and is rotatable about a rotational axis extending in the axial direction. A toner cartridge detachable from the rotary, (i) A supply-side storage chamber for storing toner, and (ii) a frame body including a discharge port communicating with the supply-side storage chamber, A toner cartridge having Having The toner regulating portion is configured to move between the cover position and the retracted position by its own weight. When the rotary with the toner cartridge mounted is in the first posture, the developing opening is positioned above the discharge port, and the self-weight of the toner regulating portion acts from the retracted position toward the cover position so that the toner regulating portion is positioned at the cover position. When the rotary with the toner cartridge attached is in the second position, the developing opening is located below the discharge port, and the toner regulating portion is located at the retracted position. The weight of the toner regulating portion acts from the cover position toward the retracted position, allowing the toner discharged from the discharge port to enter the receiving-side storage chamber. The toner regulating portion includes one end fixed to the developing frame and the other end opposite to the one end. When the toner regulating portion moves between the cover position and the retracted position, the toner regulating portion is elastically deformable between the one end and the other end. An image forming apparatus characterized by the above.

Effect of the Invention

[0009] According to the present invention, it is possible to provide a new form of image forming apparatus that develops the prior art.

Brief Description of the Drawings

[0010]

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Mode for Carrying Out the Invention

[0011] Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings.

[0012] 《Example 1》 The image forming apparatus 1 according to Example 1 will be described with reference to FIGS. 1 to 12(a, b). In the following description and each drawing, when the image forming apparatus 1 is installed on a horizontal plane, the vertical 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 main body 90 (the rotary axis direction), 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.

[0013] (Overall Configuration of the 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 having different sizes and materials can be used, such as paper such as 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.

[0014] The schematic configuration and the image forming operation of the image forming apparatus 1 will be described with reference to FIGS. 1, 2, and 3. FIG. 1 is a schematic view showing a cross-sectional configuration of the image forming apparatus 1. FIG. 2 is a view for explaining the drive source of the image forming apparatus 1. FIG. 3 is a conceptual view showing a configuration for supplying toner from the toner cartridge 70 to the developing unit 50.

[0015] As shown in FIG. 1, the image forming apparatus 1 has an image forming apparatus main body (hereinafter, the apparatus main body) 1A and toner cartridges 70y, 70m, 70c, and 70k that are detachable from the apparatus main body 1A. The apparatus main body 1A of this embodiment is the part of the image forming apparatus 1 excluding the toner cartridges 70y, 70m, 70c, and 70k.

[0016] The apparatus main body 1A of the image forming apparatus 1 includes an electrophotographic photoreceptor (hereinafter referred to as a photosensitive drum) 2 having a drum shape (cylindrical shape) as an image carrier that carries an electrostatic latent image. Around the photosensitive drum 2, a charging roller 3, a scanner 4 as an exposure device, and a cleaning unit 6 are arranged.

[0017] The charging roller 3 is an example of a charging means or a charging unit for uniformly charging the photosensitive drum 2. The scanner 4 is an example of an exposure means or an exposure unit that irradiates the photosensitive drum 2 with laser light according to image information to perform exposure. 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 or a cleaning portion that removes toner remaining on the surface of the photosensitive drum 2.

[0018] Furthermore, the apparatus main body 1A includes a sheet storage unit 300, a pickup roller 310, a feed roller 311, a separation roller 312, a pair of conveyance rollers 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 or a feeding unit that feeds the sheet S. The feed roller 311 and the separation roller 312 are examples of a separation conveyance unit that conveys the sheet S one by one while separating it by frictional force. The secondary transfer roller 12 is an example of a transfer means or a transfer unit that transfers an image from the intermediate transfer belt 10a to the sheet S.

[0019] 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 an image transferred (primary transfer) from the photosensitive drum 2 and conveys it for transfer (secondary transfer) to the sheet S. The intermediate transfer belt 10a is stretched between the belt drive roller 10b and the tension roller 10c. The belt drive roller 10b is a drive member that conveys the intermediate transfer belt 10a by being rotationally driven by a drive source.

[0020] The apparatus main body 1A also includes a rotary main body (rotary body, rotating body, developing device) 90 having developing units 50y, 50m, 50c, and 50k. As will be described later, in this embodiment, trays (support members) 80y, 80m, 80c, and 80k are attached to the rotary main body 90. Toner cartridges 70y, 70m, 70c, and 70k are removably mounted on the trays 80y, 80m, 80c, and 80k.

[0021] In the following description, a plurality of members or the like having similar functions can be distinguished by numbering. For example, one of the toner cartridges 70y, 70m, 70c, and 70k can be called the first toner cartridge, one of the remaining three can be called the second toner cartridge, one of the remaining two can be called the third toner cartridge, and the last one can be called the fourth toner cartridge. Similarly, one of the trays 80y, 80m, 80c, and 80k can be called the first tray, one of the remaining three can be called the second tray, one of the remaining two can be called the third tray, and the last one can be called the fourth tray. That is, one of the trays 80y to 80k is an example of a first support member, another one of the trays 80y to 80k is an example of a second support member, yet another one of the trays 80y to 80k is an example of a third support member, and the last one of the trays 80y to 80k is an example of a fourth support member. These numberings are only for convenience in description and can be appropriately interchanged in principle.

[0022] The developing units (first to fourth developing units) 50y, 50m, 50c, and 50k are examples of developing means or a developing section that develop (visualize) an electrostatic latent image formed on the photosensitive drum 2 into a toner image using toner of a 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. The developing units 50y, 50m, 50c, and 50k may be arranged in an order different from the order shown in FIG. 1.

[0023] The developing unit 50y includes a developing roller 51y, a supply roller 52y, and a developing blade. The developing roller 51y is a developer carrier that rotates while carrying toner as a developer and supplies it to the photosensitive drum 2. The supply roller 52y is a supply member that is disposed in contact with the developing roller 51y and supplies toner to the developing roller 51y. The developing blade 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, and 51k, supply rollers 52m, 52c, and 52k, and developing blades.

[0024] Toner cartridges 70y, 70m, 70c, and 70k corresponding to the developing units 50y, 50m, 50c, and 50k are mounted on the rotary main body 90. Inside the toner cartridges 70y, 70m, 70c, and 70k, yellow toner, magenta toner, cyan toner, and black toner are respectively accommodated as toner for replenishing the developing units 50y, 50m, 50c, and 50k. One of the four-color toners can be referred to as the first toner, one of the remaining three-color toners can be referred to as the second toner, one of the remaining two-color toners can be referred to as the third toner, and the last toner can be referred to as the fourth toner. For example, the black toner can be an example of the first toner, and the magenta toner can be an example of the second toner. These numberings are only used for convenience in explanation and can be appropriately interchanged in principle.

[0025] Here, the rotary main 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 rotary support.

[0026] In addition, trays 80y, 80m, 80c, and 80k are attached to the rotary main body 90. The portion combining the rotary main body 90 and the trays 80y, 80m, 80c, and 80k can be called a rotary unit 90U. In other words, the rotary unit 90U includes the rotary main body 90 and the trays 80y, 80m, 80c, and 80k.

[0027] The toner cartridges 70y to 70k are detachably held in the trays 80y to 80k. As will be described later, the trays 80y to 80k are slidably supported to the outside of the rotary main body 90. The portion combining the rotary unit 90U and the toner cartridges 70y, 70m, 70c, 70k can be called the rotary assembly 90A. In other words, the rotary assembly 90A has the rotary unit 90U and the toner cartridges 70y, 70m, 70c, 70k.

[0028] As will be described later, the rotary main body 90 is rotatable around the rotation axis (rotation center) 90C. The rotation axis 90C coincides with the rotation axes of the rotary frame 90f, the rotary unit 90U, and the rotary assembly 90A. Further, the rotation axis 90C is substantially parallel to the rotation axis (rotation center) of the photosensitive drum 2.

[0029] By rotating around the rotation axis 90C, the rotary main body 90 can take a developing posture in which any one of the developing rollers 51y, 51m, 51c, 51k faces the photosensitive drum 2. The posture in which the developing roller 51y faces the photosensitive drum 2 is called the yellow developing posture. The posture in which the developing roller 51m faces the photosensitive drum 2 is called the magenta developing posture. The posture in which the developing roller 51c faces the photosensitive drum 2 is called the cyan developing posture. The posture in which the developing roller 51k faces the photosensitive drum 2 is called the black developing posture. That is, the rotary main body 90 can rotate around the rotation axis 90C so that the positions of the developing rollers 51y, 51m, 51c, 51k with respect to the photosensitive drum 2 change. The black developing posture is an example of the first developing posture in which the first developing roller (developing roller 51k) faces the photosensitive drum 2. The other developing postures are examples of the second developing postures in which the second developing rollers (developing rollers 51y to 51c) face the photosensitive drum 2. The yellow / magenta / cyan / black developing postures can also be called the first to fourth developing postures. These numberings are only for convenience in explanation and can be changed as appropriate in principle.

[0030] As shown in FIG. 2, the apparatus main body 1A has motors M1, M2, and M3 as drive sources. As will be described later, the motor M1 supplies a driving force for rotating the rotary main body 90 around the rotation axis 90C. In other words, the motor M1 rotates the rotary assembly 90A and the rotary unit 90U around the rotation axis 90C.

[0031] Further, the apparatus main body 1A has a drive device 98 including the motor M2 and a transmission device. The transmission device includes drive racks 15L and 15R as drive gears to be described later, 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 main body 90 via the drive racks 15L and 15R.

[0032] The motor M3 drives members other than the members driven by the motors M1 and M2. For example, the motor M3 drives the photosensitive drum 2, the developing units 50y, 50m, 50c, and 50k, the pickup roller 310, the feed roller 311, the pair of conveyance rollers 320, the secondary transfer roller 12, the belt drive roller 10b, and the fixing device 40.

[0033] Note that the members driven by the motors M1, M2, and M3 can be changed as appropriate. Also, the roles of any two or all three of the motors M1, M2, and M3 can be consolidated into one motor. On the other hand, a drive source other than the motors M1, M2, and M3 may be added.

[0034] Here, the subscripts y, m, c, k attached to the developing units 50y, 50m, 50c, 50k, the toner cartridges 70y, 70m, 70c, 70k, the trays 80y, 80m, 80c, 80k, etc. indicate the color of the toner. The basic configurations and functions of the developing units 50y, 50m, 50c, 50k are common. The basic configurations and functions of the toner cartridges 70y, 70m, 70c, 70k are common. Also, the basic configurations and functions of the trays 80y, 80m, 80c, 80k are common. Therefore, when there is no need to distinguish them, the subscripts y, m, c, k are omitted and described as any one of the four units, cartridges, and trays.

[0035] As shown in FIG. 3, the toner cartridge 70 has a toner frame 71. The toner frame 71 includes a toner storage portion 71a for storing toner and a discharge opening 71b communicating with the toner storage portion 71a.

[0036] The developing unit 50 has a developing frame (accommodation frame) 53. The developing frame 53 includes a developing side accommodation portion 53a and a receiving opening 53b communicating with the developing side accommodation portion (toner supply chamber) 53a. As described above, the developing unit 50 has a developing roller 51, a supply roller 52, etc., but these members are omitted in FIG. 3.

[0037] 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 (FIG. 4(a)) of the developing unit 50k provided with the developing side accommodation portion 53a is an example of a first accommodation frame provided with a first accommodation portion. The developing frame 53m (FIG. 4(a)) of the developing unit 50m provided with the developing side accommodation portion 53a is an example of a second accommodation frame provided with a second accommodation portion. The rotary body 90 is an example of a rotatable rotary having a first developing roller, a second developing roller, a first accommodation frame provided with a first accommodation portion, and a second accommodation frame provided with a second accommodation portion. In this embodiment, the rotary body 90 has first to fourth developing rollers and first to fourth accommodation frames.

[0038] As described below, the toner cartridge 70 is movable relative to the developing frame 53 between a mounting position and a retracted position retracted from the mounting position. In a state where the toner cartridge 70 is in the mounting position relative to the developing frame 53, the discharge opening 71b faces the receiving opening 53b. That is, the toner storage portion 71a of the toner cartridge 70 and the developing-side storage portion 53a of the developing unit 50 communicate with each other via the discharge opening 71b and the receiving opening 53b. When toner is replenished from the toner cartridge 70 to the developing unit 50, at least a part of the receiving opening 53b is positioned below at least a part of the discharge opening 71b.

[0039] Then, the toner stored in the toner storage portion 71a is discharged from the discharge opening 71b, and the toner discharged from the discharge opening 71b is stored in the developing-side storage portion 53a through the receiving opening 53b. The toner stored in the developing-side storage portion 53a is supplied to the developing roller 51 by the supply roller 52. Through such a path, the toner stored in the toner storage portion 71a is supplied to the developing roller 51.

[0040] The toner cartridge 70 preferably has a sealing member (first sealing member), not shown, that covers the discharge opening 71b. Further, the developing unit 50 preferably has a sealing member (second sealing member), not shown, that covers the receiving opening 53b.

[0041] In a state where the toner cartridge 70 is not mounted on the developing unit 50, it is desirable that the discharge opening 71b and the receiving opening 53b are each covered with a sealing member so as to suppress the outflow of toner from the discharge opening 71b and the receiving opening 53b.

[0042] (Image forming operation) The image forming operation in this embodiment will be described. First, the photosensitive drum 2 is rotated in the direction of the arrow in FIG. 1 (counterclockwise) 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.

[0043] When forming a color image on the sheet S, as follows, the rotary main body 90 rotates in the direction of the arrow in FIG. 1 (clockwise) while supporting the developing units 50y, 50m, 50c, and 50k. Then, while moving the developing rollers 51y, 51m, 51c, and 51k to the developing positions one by one, the electrophotographic process is repeated.

[0044] First, the scanner 4 irradiates laser light based on the image data corresponding to the yellow image, and forms 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 main body 90, and the rotary main body 90 takes the yellow developing posture. When the rotary main body 90 takes the yellow developing posture, the developing roller 51y is in the developing position, and develops the electrostatic latent image formed on the photosensitive drum 2 with yellow toner.

[0045] Here, in this embodiment, each of the developing rollers 51y, 51m, 51c, and 51k is an elastic roller with rubber coated around a metal shaft. At the developing position, each of the developing rollers 51y, 51m, 51c, and 51k develops the electrostatic latent image in a state of being in contact with the photosensitive drum 2. That is, the contact developing method is adopted in the image forming apparatus 1 in this embodiment. However, at the developing position, each of the developing rollers 51y, 51m, 51c, and 51k may develop the electrostatic latent image in a state where there is a gap between the developing rollers and the photosensitive drum 2. That is, the image forming apparatus 1 may adopt a non-contact developing method.

[0046] When the yellow toner image is developed, the yellow toner image on the photosensitive drum 2 is primarily transferred to the intermediate transfer belt 10a by the primary transfer roller 11 disposed inside the intermediate transfer belt 10a.

[0047] After this, by rotating the rotary body 90 to move the developing rollers 51m, 51c, and 51k to the developing positions in order, toner images of each color are formed. That is, after the yellow toner image is formed on the intermediate transfer belt 10a, the rotary body 90 assumes the magenta developing posture, and the magenta toner image is formed on the intermediate transfer belt 10a. After the magenta toner image is formed on the intermediate transfer belt 10a, the rotary body 90 assumes the cyan developing posture, and the cyan toner image is formed on the intermediate transfer belt 10a. After the cyan toner image is formed on the intermediate transfer belt 10a, the rotary body 90 assumes the black developing posture, and the black toner image is formed on the intermediate transfer belt 10a. After the black toner image is formed on the intermediate transfer belt 10a, the rotary body 90 rotates around the rotation axis 90C in the direction of the arrow shown in FIG. 1 (clockwise) and returns to the yellow developing posture. Note that the color of the image first formed on the intermediate transfer belt 10a is arbitrary, and for example, a black toner image may be formed first.

[0048] Then, primary transfer is repeated so as to overlap the four-color toner images on the intermediate transfer belt 10a, and a color image is formed on the intermediate transfer belt 10a. Note that until the color image is formed on the intermediate transfer belt 10a, the secondary transfer roller 12 and the cleaning device 13 are not in contact with the intermediate transfer belt 10a.

[0049] On the other hand, the sheet S is fed from the sheet storage unit 300 provided at the lower part of the apparatus main body 1A by the pickup roller 310. The sheet S is separated one by one by the feed roller 311 and the separation roller 312 and sent to the pair of conveyance rollers 320. The pair of conveyance rollers 320 sends the fed sheet S to the transfer part (secondary transfer part), which is the nip part between the intermediate transfer belt 10a and the secondary transfer roller 12. The color image on the intermediate transfer belt 10a is transferred (secondary transferred) onto the surface of the conveyed sheet S.

[0050] 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 pressed, and the image is fixed on the sheet S. The sheet S that has passed through the fixing device 40 is discharged outside the image forming apparatus 1 as a finished product.

[0051] On the other hand, when forming a monochrome image on the sheet S, the rotary main body 90 assumes a black developing posture. In this state, after an electrostatic latent image is formed on the surface of the photosensitive drum 2 by charging and exposure of the photosensitive drum 2, the electrostatic latent image is developed with black toner by the developing roller 51k located at 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 those in the case of the color image.

[0052] (Rotary configuration) The configuration of the rotary main body 90 will be described with reference to FIGS. 1, 4(a, b), and 5.

[0053] FIGS. 4(a, b) are cross-sectional views showing the rotary main body 90 of the image forming apparatus 1 and its periphery. Note that FIGS. 4(a, b) are cross-sectional views of the apparatus cut by a virtual plane perpendicular to the rotation axis 90C of the rotary main body 90. FIG. 5 is a perspective view of the rotary main body 90.

[0054] As described above, the toner cartridges 70y to 70k are detachable from the rotary main body 90. When the toner in the toner cartridges 70y to 70k runs out, the user can supply toner to the image forming apparatus 1 by replacing the toner cartridges 70y to 70k.

[0055] As shown in FIG. 1, the apparatus main body 1A has a frame 16 that houses the rotary main body 90. The frame 16 is the main body frame of the image forming apparatus 1 of the present embodiment. The frame 16 is the housing (body) of the apparatus main body 1A composed of a frame and exterior members, and is substantially rectangular parallelepiped-shaped in the present embodiment.

[0056] The frame body 16 is provided with an opening 16a. More specifically, the frame body 16 is provided with side surfaces 16b that extend in a direction intersecting the horizontal direction. The side surfaces 16b constitute at least a part of the outer surface on the +X side of the apparatus main body 1A. The opening 16a is disposed on this side surface 16b. The side surface 16b is a side surface disposed on the downstream side of the discharge port in the discharge direction in which the sheet S on which an image is formed is discharged from the discharge port of the apparatus main body 1A. The user can access the sheet storage unit 300 from the side of the side surface 16b of the image forming apparatus 1 to replenish the sheet S or acquire the sheet S discharged from the discharge port. Therefore, the side surface 16b can be referred to as the front (front surface) of the apparatus main body 1A.

[0057] The toner cartridges 70y, 70m, 70c, and 70k are detachable from the rotary main body 90 through the opening 16a. That is, it can be said that the toner cartridge 70k is an example of a first toner cartridge that stores toner supplied to the first developing roller (developing roller 51k) and is detachable from the rotary (rotary main body 90) through the opening 16a of the frame body 16 of the apparatus main body 1A. The toner cartridge 70m is an example of a second toner cartridge that stores toner supplied to the second developing roller (developing roller 51m) and is detachable from the rotary (rotary main body 90) through the opening 16a of the frame body 16 of the apparatus main body 1A.

[0058] In this embodiment, the toner cartridges 70y, 70m, 70c, and 70k are detached from and attached to the rotary main body 90 through the opening 16a while being supported by the trays 80y to 80k.

[0059] In other words, the user can detach and attach the toner cartridges 70y to 70k to and from the rotary main body 90 via the trays 80y to 80k.

[0060] The opening 16a is disposed on the side surface 16b of the frame 16. In the present embodiment, the side surface 16b is a plane substantially parallel to the rotation axis 90C of the rotary body 90. For this reason, when the toner cartridge 70 is replaced, the toner cartridge 70 passes through the opening 16a in a direction (preferably perpendicular direction) intersecting the rotation axis 90C.

[0061] 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 movable between a closed position covering the opening 16a (see also Fig. 6(a)) and an open position where the opening 16a is exposed (see also Fig. 6(b, c)).

[0062] As described above, in the present embodiment, the toner cartridge 70 is configured to be detachable from the rotary body 90 via the tray 80. For this reason, the toner cartridge 70 can be stably attached to and detached from the rotary body 90.

[0063] More specifically, the user can replace the toner cartridge 70 by an operation of attaching and detaching the toner cartridge 70 to and from the tray 80 that is configured to be movable with respect to the rotary body 90 (that is, with respect to the apparatus main body 1A). In the case of a configuration in which the user directly inserts and removes the toner cartridge with respect to the apparatus main body, the user is required to insert the toner cartridge to a predetermined mounting position within the apparatus main body. In the present embodiment, the tray 80 is movable such that the toner cartridge 70 moves to the mounting position while supporting the toner cartridge 70. Therefore, the user can replace the toner cartridge 70 by a simple operation of placing the toner cartridge 70 on the tray 80, and the operability is improved.

[0064] Note that the toner cartridge 70 is shaped to be elongated with the Y direction parallel to the rotation axis 90C of the rotary main body 90 as the longitudinal direction. That is, the longitudinal dimension of the toner cartridge 70 is larger than the height and width in the cross section orthogonal to the longitudinal direction. When handling the toner cartridge 70 having such an elongated shape, by arranging the opening 16a on the side surface 16b of the frame body 16 substantially parallel to the longitudinal direction (Y direction) of the toner cartridge 70, the toner cartridge 70 can pass through the opening 16a with a short moving distance. For example, compared with the case of inserting and removing the toner cartridge 70 through an opening provided on one side (+Y side or -Y side) of the frame body 16 in the longitudinal direction of the toner cartridge 70, the replacement of the toner cartridge 70 becomes easier.

[0065] The rotary main body 90 can rotate around the rotation axis 90C and take an exchange posture in which any one of the toner cartridges 70y to 70k can be removed from the rotary main body 90. The posture in which the removal of the toner cartridge 70y is allowed is called the yellow exchange posture. The posture in which the removal of the toner cartridge 70m is allowed is called the magenta exchange posture. The posture in which the removal of the toner cartridge 70c is allowed is called the cyan exchange posture.

[0066] The posture in which the removal of the toner cartridge 70k is allowed is called the black exchange posture. The black exchange posture is an example of the first exchange posture in which the removal of the first toner cartridge from the rotary main body 90 is allowed. The yellow / magenta / cyan exchange postures are examples of the second exchange postures in which the removal of the second toner cartridge from the rotary main body 90 is allowed. The yellow / magenta / cyan / black exchange postures can also be called the first to fourth exchange postures. These numberings are only for convenience in explanation and can be appropriately interchanged in principle.

[0067] The rotary main body 90 rotates clockwise in FIG. 1 around the rotation axis 90C and can sequentially take the yellow / magenta / cyan / black replacement postures. In the present embodiment, the rotary main body 90 rotates clockwise in FIG. 1 around the rotation axis 90C, so that the developing posture and the replacement posture are alternately switched. For example, in FIG. 1, the rotary main body 90 is in the black developing posture. From this state, when the rotary main body 90 rotates clockwise, the posture of the rotary main body 90 is switched in the order of cyan replacement posture, yellow developing posture, black replacement posture, magenta developing posture, yellow replacement posture, cyan developing posture, magenta replacement posture. When the rotary main body 90 rotates clockwise from the magenta replacement posture, the rotary main body 90 returns to the black developing posture. That is, the rotary main body 90 can rotate one or more turns (360°) clockwise.

[0068] FIG. 4(a) shows a cross-section of the rotary main body 90 in the developing posture (specifically, the yellow developing posture). FIG. 4(b) shows a cross-section of the rotary main body 90 in the replacement posture (specifically, the black replacement posture).

[0069] As shown in FIGS. 4(a, b), four trays 80y to 80k are attached to the rotary main body 90. Toner cartridges 70y to 70k are respectively held in the trays 80y to 80k. In FIGS. 4(a, b), the trays 80y to 80k are in a state of being housed inside the rotary main body 90, and this state can be said to be a state where the toner cartridges 70y to 70k are attached to the developing units 50y, 50m, 50c, 50k.

[0070] As described above, the toner cartridge 70 is movable relative to the developing frame 53 of the developing unit 50 between a mounting position and a retracted position retracted from the mounting position. That is, the first toner cartridge (toner cartridge 70k) is movable relative to the first housing frame (developing frame 53k) between a first mounting position and a first retracted position. The second toner cartridge (toner cartridge 70m) is movable relative to the second housing frame (developing frame 53m) between a second mounting position and a second retracted position.

[0071] When the toner cartridge 70 is in the mounting position relative to the developing frame 53, as shown in FIG. 3, the discharge opening 71b and the receiving opening 53b face each other. In this state, the toner cartridge 70 is configured to supply toner to the developing-side housing portion 53a through the receiving opening 53b (the opening of the housing frame).

[0072] The apparatus main body 1A has a moving device 85 configured to move the toner cartridge 70 from the mounting position to the retracted position relative to the rotary main body 90 (more specifically, relative to the developing frame 53 of the developing unit 50). The moving device 85 will be described later with reference to FIG. 8 and the like. In the present embodiment, a plurality of moving devices 85y to 85k corresponding to a plurality of toner cartridges 70y to 70k are arranged on the rotary main body 90. The trays 80y to 80k can be said to be a part of the moving devices 85y to 85k.

[0073] In the present embodiment, the toner cartridge 70k containing black toner is larger in size than the toner cartridges 70y to 70c containing yellow toner, magenta toner, and cyan toner, and can accommodate more toner. In other words, the first toner cartridge can accommodate a first amount of toner, the second toner cartridge can accommodate a second amount of toner, and it can be said that the first amount is more than the second amount.

[0074] Specifically, the length of the black toner cartridge 70k in the first radial direction with respect to the rotation axis 90C of the rotary body 90 is greater than the length of the magenta toner cartridge 70m in the second radial direction. Here, the first radial direction is the radial direction of the rotary radius of the rotary body 90 (the radial direction of the virtual circle centered on the rotation axis 90C), and it is the direction in which the toner cartridge 70k extends with respect to the rotation axis 90C when viewed in the direction of the rotation axis 90C. The second radial direction is the radial direction of the rotary radius of the rotary body 90, and it is the direction in which the toner cartridge 70m extends with respect to the rotation axis 90C when viewed in the direction of the rotation axis 90C. Similarly, the length of the black toner cartridge 70k in the first radial direction is greater than the lengths of the toner cartridges 70y and 70c in the radial directions corresponding to the other toner cartridges 70y and 70c.

[0075] Therefore, the tray 80k for holding the black toner cartridge 70k is larger in size than the trays 80y to 80c for holding the other toner cartridges 70y, 70m, and 70c. That is, four toner cartridges 70y to 70k and trays 80y to 80k of different sizes are arranged in the rotary body 90. In other words, the rotary body 90 is detachable from the toner cartridge 70k as an example of the first toner cartridge and the toner cartridge 70y as an example of the second toner cartridge that is smaller in size than the first toner cartridge. Accordingly, the rotary body 90 is provided with a tray 80k as an example of the first support member for supporting the first toner cartridge and a tray 80y as an example of the second support member that is smaller in size than the first support member. Further, the rotary body 90 is detachable from the toner cartridges 70m and 70c as examples of the third toner cartridge and the fourth toner cartridge that are smaller in size than the first toner cartridge. Accordingly, the rotary body 90 is provided with trays 80m and 80c as examples of the third support member and the fourth support member that are smaller in size than the first support member.

[0076] Here, with reference to FIG. 5, the rotational drive of the rotary body 90 will be described. As shown in FIG. 5, disk gears 92L and 92R are formed at both ends of the rotary body 90. Further, rotary drive gears 93L and 93R are connected to both ends of the swing shaft 91 in a manner that allows drive transmission. Here, the driving force of the motor M1 is transmitted to the rotary drive gear 93R by the drive transmission mechanism. Next, the driving force is transmitted from the rotary drive gears 93L and 93R to the disk gears 92L and 92R, thereby rotationally driving the rotary body 90. The rotary body 90 rotates around the rotation axis 90C in the clockwise direction in FIG. 1.

[0077] Further, the rotary body 90 is supported so as to be swingable about the swing shaft 91. The rotary body 90 is biased by a biasing member (not shown) in the counterclockwise direction in FIGS. 4(a) and 4(b) about the swing shaft 91. This direction can be said to be 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 posture, each of the developing rollers 51y to 51k contacts the photosensitive drum 2.

[0078] On the other hand, as shown in FIG. 5, rotary cams 90eL and 90eR are provided at both ends of the rotary body 90. When the rotary body 90 rotates clockwise in FIGS. 4(a) and 4(b) about the rotation axis 90C, the rotary cams 90eL and 90eR contact the rollers 96 (shown in FIGS. 4(a) and 4(b)) supported by the frame body 16. Then, it moves in the clockwise direction in FIGS. 4(a) and 4(b) about the swing shaft 91. This direction can be said to be the direction in which each of the developing rollers 51y to 51k moves away from the photosensitive drum 2. Also, this direction can be said to be the direction in which the rotary body 90 approaches the opening 16a of the frame body 16 and the door 14.

[0079] Thereby, when the rotary body 90 rotates and switches from the developing posture to the replacement posture, the rotary body 90 swings about the swing shaft 91. When the rotary body 90 is in the replacement posture, the developing roller 51 is separated from the photosensitive drum 2.

[0080] As shown in FIG. 4(b), in the black replacement posture, the toner cartridge 70k stops at a position facing the opening 16a and the door 14 provided on the side surface 16b of the apparatus main body 1A. From this state, when the tray 80k is slid and moved from the mounting position to the developing unit 50k to the outside of the rotary main body 90, the user can replace the toner cartridge 70k.

[0081] (Toner Cartridge Replacement Operation) The toner cartridge replacement operation will be described with reference to FIGS. 4(a), 6(a - c), and 7(a, b). FIGS. 6(a - c) are external views of the apparatus main body 1A. FIGS. 7(a, b) are cross-sectional views around the rotary main body 90 when the toner cartridge is replaced. Note that FIGS. 7(a, b) are cross-sectional views of the apparatus in a virtual plane perpendicular to the rotation axis 90C of the rotary main body 90.

[0082] FIG. 6(a) shows the external appearance of the apparatus main body 1A during the image forming operation and in the standby state. The image forming operation period is the period during which the image forming apparatus 1 feeds the sheet S, forms an image on the sheet S, and then discharges it as a product. The standby state is a state in which the image forming apparatus 1 can start the image forming operation when it receives an image forming instruction (printing instruction), and is waiting for an image forming instruction from the user. As shown in FIG. 6(a), during the image forming operation and in the standby state, the door 14 is in the closed state.

[0083] FIG. 6(b) shows the external appearance of the apparatus main body 1A when the toner cartridge is replaced. When the toner cartridge is replaced, the door 14 is in the open state, and the tray 80 and the toner cartridge 70 are moved to the outside of the apparatus main body 1A.

[0084] The toner cartridge 70 is movable relative to the developing frame 53 of the developing unit 50 between a mounting position and a retracted position retracted from the mounting position. When the toner cartridge 70 is in the mounting position relative to the developing frame 53, as shown in FIG. 3, the discharge opening 71b and the receiving opening 53b face each other. As shown in FIGS. 4(a, b), the rotary main body 90 is configured to rotate around the rotation axis 90C and assume a developing posture or an exchange posture when the toner cartridge 70 is in the mounting position.

[0085] The replacement operation of the toner cartridge will be described. First, the user instructs the control unit of the apparatus main body 1A to perform the toner cartridge replacement operation. The instruction for the toner cartridge replacement operation is performed, for example, by input via an operation panel (operation unit) provided on the apparatus main body 1A.

[0086] When the control unit receives the instruction for the toner cartridge replacement operation, the rotary main body 90 rotates to the replacement posture of the toner cartridge 70 to be replaced (the toner cartridge 70 with no toner left) and stops. That is, the control unit rotates the rotary main body 90 to the replacement posture of the toner cartridge specified in the instruction for the toner cartridge replacement operation (the black replacement posture for replacing the black toner cartridge 70k in FIG. 4(b)). In the replacement posture, the tray 80 that supports the toner cartridge 70 for which replacement has been instructed faces the opening 16a of the frame 16 of the apparatus main body 1A.

[0087] For example, the rotary main body 90 in Fig. 4(a) is in the yellow developing posture where the yellow developing roller 51y faces the photosensitive drum 2. At this time, the black toner cartridge 70k and the tray 80k do not necessarily face the opening 16a and the door 14. In other words, the toner cartridge 70 and the tray 80 do not necessarily face the opening 16a and the door 14 when the rotary main body 90 is in an exchanging posture other than the exchanging posture of the toner cartridge or in a developing posture. Therefore, the opening 16a only needs to be large enough for each toner cartridge 70 to pass through individually. When the rotary main body 90 rotates a predetermined angle clockwise in the figure from the yellow developing posture, as shown in Fig. 4(b), the black toner cartridge 70k and the tray 80k face the opening 16a and the door 14.

[0088] Here, "the tray 80 faces the opening 16a" means that the tray 80 is positioned so as to be movable outside the apparatus main body 1A through the opening 16a. That is, when the tray 80 faces the opening 16a, the tray 80 is moved outward in the radial direction of the rotation radius of the rotary main body 90 by a moving mechanism described later, so that the tray 80 and the toner cartridge 70 supported by the tray 80 can protrude outside the apparatus main body 1A. In Fig. 4(a), none of the trays 80y to 80k face the opening 16a. In Fig. 4(b), only the black tray 80k faces the opening 16a, and the other trays 80y to 80c do not face the opening 16a.

[0089] When the rotary main body 90 is positioned in the exchanging posture, the motor M2 moves the tray 80 that supports the toner cartridge 70 to be exchanged outward toward the outside of the apparatus main body 1A. Thereby, the toner cartridge 70 to be exchanged moves from the mounting position to the retracted position with respect to the rotary main body 90. Also, as shown in Figs. 6(b, c) and 7(a, b), the tray 80 and the toner cartridge 70 to be exchanged supported by the tray 80 protrude outside the apparatus main body 1A through the opening 16a.

[0090] More specifically, the tray 80 is movable relative to the rotary body 90 between a storage position and a take-out position. The storage position is a position where the tray 80 is stored inside the rotary body 90. The take-out position is a position where the tray 80 protrudes outside the rotary body 90 and the toner cartridge 70 can be taken out from the tray 80 (removal position, replaceable position). Examples of the storage position are the positions of the trays 80y to 80k in FIGS. 4(a, b). Examples of the take-out position are the positions of the tray 80 in FIGS. 6(b, c), the tray 80k in FIG. 7(a), and the tray 80m in FIG. 7(b).

[0091] When the tray 80 is in the storage position, the toner cartridge 70 attached to the tray 80 is in the mounted position. When the tray 80 is in the take-out position, the toner cartridge 70 attached to the tray 80 is in the retracted position.

[0092] Here, as shown in FIGS. 7(a, b), the rotary body 90 has a convex portion 95 for holding the tray 80 in the storage position and holding the toner cartridge 70 in the mounted position. As shown in FIG. 8, the tray 80 is provided with a concave portion 87 that fits into the convex portion 95. In FIGS. 7(a, b), the convex portions 95k and 95m corresponding to the trays 80k and 80m are shown, and in FIG. 8, the concave portions 87y and 87m of the trays 80y and 80m are shown. However, the convex portion 95 and the concave portion 87 are provided for each of the trays 80y to 80k. The convex portion 95 is preferably biased in a direction to engage with the concave portion 87.

[0093] When the convex portion 95 fits into the concave portion 87 of the tray 80, the tray 80 is locked to the rotary frame body 90f. Thereby, even when the rotary body 90 rotates, the tray 80 remains in the storage position, and the toner cartridge 70 is prevented from moving from the mounted position. When the tray 80 is moved between the storage position and the take-out position by a moving device described later, the convex portion 95 can be configured to be moved by the tray 80 and the convex portion 95 is disengaged from the concave portion 87.

[0094] In this embodiment, the door 14 is rotatably supported with respect to the apparatus main body 1A. As shown in FIG. 7(a), the door 14 is biased by a spring 14s from the open position toward the closed position. The spring 14s is, for example, a tension spring, and biases the door 14 about the support shaft 14c of the door 14 to generate a moment in the counterclockwise direction in FIGS. 7(a) and 7(b).

[0095] When the tray 80 pushes the door 14, the door 14 is in an open state (the state shown in FIG. 6(b)). This state can also be said to be a state in which the tray 80 is supported by the door 14. By the door 14 supporting at least a part of the tray 80 protruding outside the apparatus main body 1A, the toner cartridge 70 can be supported more stably. In other words, when the first toner cartridge (toner cartridge 70k) is in the first retracted position, the opening / closing member (door 14) in the open position supports the first support member (tray 80k). Also, when the second toner cartridge (toner cartridges 70y to 70c) is in the second retracted position, the opening / closing member (door 14) in the open position supports the second support members (trays 80y to 80c).

[0096] Note that the door 14 is configured to abut against a part of the frame body 16 of the apparatus main body 1A (for example, the lower edge 16c of the opening 16a) in the open position and not to rotate downward beyond the open position. When the tray 80 is pulled back from the outside to the inside of the apparatus main body 1A, the door 14 returns to the closed position by the biasing force of the spring 14s.

[0097] The toner cartridge 70 is detachably held on the tray 80. Therefore, as shown in FIG. 6(c), the user can remove the toner cartridge 70 from the tray 80 and perform an operation (replacement operation) of attaching a new toner cartridge 70. When replacing a plurality of toner cartridges 70, the replacement operation can be performed by repeating the above operation.

[0098] Figs. 7(a) and 7(b) show cross-sections around the rotary body 90 when replacing the toner cartridge. Fig. 7(a) shows the state when replacing the black toner cartridge 70k. Fig. 7(b) shows the state when replacing the magenta toner cartridge 70m.

[0099] The image forming apparatus 1 includes a moving device 85 (Fig. 8) that moves the toner cartridge 70 from the mounting position to the retracted position. In this embodiment, it can be said that the moving device 85 includes the tray 80. The moving device 85k including the tray 80k can be said to be an example of a first moving device including a first support member. The moving device 85m including the tray 80m can be said to be an example of a second moving device including a second support member.

[0100] Even when the toner cartridge 70 is in the retracted position, the tray 80 is in a state of being connected to the rotary body 90 (a state supported by the rotary body 90). In order to easily perform the operation of removing the toner cartridge 70 from the rotary body 90, it is preferable that the length by which the toner cartridge 70 protrudes from the rotary body 90 is long at the retracted position. Since the toner cartridge 70 is detachably configured to the rotary body 90 via the tray 80, even when the length by which the toner cartridge 70 protrudes from the rotary body 90 is long, the toner cartridge 70 can be stably supported by the tray 80.

[0101] The moving direction of the toner cartridge 70 when it moves from the mounting position to the retracted position is called the retracting direction. In this embodiment, the retracting direction of the toner cartridge 70 is a direction intersecting the direction of the rotation axis 90C (Y direction). Therefore, as shown in Figs. 7(a) and 7(b), when viewed in the direction of the rotation axis 90C (Y direction), the retracting direction of the toner cartridge 70 is a direction orthogonal to the direction of the rotation axis 90C (Y direction). Also, it can be said that the retracting direction of the toner cartridge 70 is a direction outward in the radial direction of rotation of the rotary body 90 (a direction away from the rotation axis 90C).

[0102] As shown in FIGS. 7(a) and 7(b), when the user performs an operation to remove the toner cartridge 70 from the rotary main body 90, at least a part of the toner cartridge 70 preferably protrudes from the rotary main body 90 when the toner cartridge 70 is removed. In the present embodiment, when the toner cartridge 70 is in the retracted position, the entire toner cartridge 70 protrudes from the rotary main body 90.

[0103] When the rotary main body 90 rotates around the rotation axis 90C, it can be said that the rotation locus of the rotary main body 90 coincides with the circumscribed circle of the rotary main body 90 centered on the rotation axis 90C (the virtual circle 90V shown by the broken line in FIGS. 7(a) and 7(b)). When the toner cartridge 70 is in the retracted position, it is preferable that at least half of the length of the toner cartridge 70 in the retraction direction is outside the rotation locus of the rotary main body 90. That is, when viewed in the direction of the rotation axis of the rotary, in a state where the toner cartridge is in the retracted position, for the moving direction of the toner cartridge from the mounting position to the retracted position, it is preferable that at least half of the total length of the toner cartridge is located outside the rotation locus of the rotary. This applies to each toner cartridge 70 including the toner cartridge 70k as an example of the first cartridge and the toner cartridge 70m as an example of the second cartridge. Further, in the present embodiment, as shown in FIGS. 7(a) and 7(b), when the toner cartridge 70 is in the retracted position, the entire toner cartridge 70 is outside the rotation locus (virtual circle 90V) of the rotary main body 90.

[0104] Furthermore, in order for the user to easily grasp the toner cartridge 70, when the toner cartridge 70 is in the retracted position, at least a part of the toner cartridge 70 is preferably outside the image forming apparatus 1 (outside the apparatus main body 1A). Here, the outside of the apparatus refers to a space outside the image forming apparatus 1 (outside the apparatus main body 1A) when the image forming apparatus 1 is used, such as an image forming operation on the sheet S.

[0105] In this embodiment, the outer surface of the apparatus main body 1A is formed by the outer surface of the frame body 16. That is to say, the outside of the machine can also mean the outside of the frame body 16. Therefore, the state where at least a part of the toner cartridge 70 is outside the machine can also be said to be a state where at least a part of the toner cartridge 70 protrudes outward from the opening 16a of the frame body 16 of the apparatus main body 1A.

[0106] In this embodiment, when the door 14 is in the closed position, the opening 16a of the frame body 16 of the apparatus main body 1A is covered by the door 14. And a part of the outer surface of the apparatus main body 1A is formed by the outer surface 14a of the door 14 in the closed position. In this case, the outside of the machine means the outside of the outer surface 14a of the door 14 in the closed position. That is to say, if the position of the outer surface 14a of the door 14 in the closed position is taken as the appearance position, when the toner cartridge 70 is in the retracted position, at least a part of the toner cartridge 70 is located outside the apparatus main body 1A rather than at this appearance position.

[0107] In other words, at least a part of the toner cartridge 70 is located in the space that would be outside the apparatus main body 1A if the door 14 were in the closed position. And regarding the retraction direction of the toner cartridge 70, at least a part of the toner cartridge 70 is located on the downstream side of the appearance position.

[0108] Also, taking the side surface 16b provided with the opening 16a as the front of the apparatus main body 1A, when the toner cartridge 70 is in the retracted position, at least a part of the toner cartridge 70 can be said to protrude more forward than the outer surface on the front side of the apparatus main body 1A. In this case, the user can access the toner cartridge 70 from the front side of the image forming apparatus and easily perform the replacement operation of the toner cartridge 70.

[0109] Incidentally, when the toner cartridge 70 is in the retracted position, it is preferable that at least half of the length of the toner cartridge 70 in the retraction direction is outside the apparatus. That is, when viewed in the direction of the rotary axis, it is preferable that at least half of the total length of the toner cartridge is located outside the main body frame in the moving direction of the toner cartridge from the mounting position toward the retracted position with the toner cartridge in the retracted position. This applies to each toner cartridge 70 including the toner cartridge 70k as an example of the first cartridge and the toner cartridge 70m as an example of the second cartridge. Further, when the toner cartridge 70 is in the retracted position, it is more preferable that the entire toner cartridge 70 is outside the apparatus. In the present embodiment, the outer surface on the front side of the apparatus main body 1A is formed by the outer surface 14a and the side surface 16b of the door 14, but the configuration of the door 14 is not limited to this. For example, the size of the door 14 may be such that it covers the entire side surface 16b. In this case, the outer surface 14a of the door 14 forms the outer surface on the front side of the apparatus main body 1A.

[0110] The tray 80 includes a cartridge holding portion 81 (see FIGS. 3 and 6(c)) for holding the toner cartridge 70. The cartridge holding portion 81 is a portion to which the toner cartridge 70 is attached. When the tray 80 is in the take-out position, it is preferable that the entire cartridge holding portion 81 is outside the rotation locus of the rotary main body 90 in the retraction direction. When the tray 80 is in the take-out position, it is preferable that at least half of the length of the cartridge holding portion 81 is outside the apparatus in the retraction direction.

[0111] Here, as described above, the toner cartridge 70k and the tray 80k are larger in size than the other toner cartridges 70y to 70c and trays 80y to 80c. Therefore, as shown in FIGS. 7(a) and 7(b), in the present embodiment, the moving amount of the tray 80 at the time of toner cartridge replacement is changed according to the size of the toner cartridge 70.

[0112] Specifically, as shown in FIG. 7(a), the moving distance of the tray 80k (the first support member) when moving from the accommodation position (the first accommodation position) to the extraction position (the first extraction position) is L1. The moving distance of the tray 80m (the second support member) when moving from the accommodation position to the extraction position (the third extraction position) is L2. FIG. 7(b) shows the state where the toner cartridge 70m and the tray 80m have moved, but the moving distance of the trays 80y and 80c when moving from the accommodation position to the extraction position is also L2. At this time, L1 is greater than L2. In other words, it can be said that the moving distance of the first support member when the first toner cartridge moves from the first mounting position to the first retracted position is longer than the moving distance of the second support member when the second toner cartridge moves from the second mounting position to the second retracted position.

[0113] Also, as shown in FIG. 7(a), with the tray 80k in the extraction position and the toner cartridge 70k in the retracted position, the toner cartridge 70k protrudes a distance P1 outside the apparatus from the outer surface of the apparatus main body 1A. In this embodiment, the tray 80k also protrudes a distance P1 outside the apparatus from the outer surface of the apparatus main body 1A.

[0114] Also, as shown in FIG. 7(b), with the tray 80m in the extraction position and the toner cartridge 70m in the retracted position, the toner cartridge 70m protrudes a distance P2 outside the apparatus from the outer surface of the apparatus main body 1A. In this embodiment, the tray 80m also protrudes a distance P2 outside the apparatus from the outer surface of the apparatus main body 1A. Note that the toner cartridges 70y and 70c also protrude a distance P2 outside the apparatus from the outer surface of the apparatus main body 1A.

[0115] The above distance P1 is greater than the distance P2. That is, the length by which the first toner cartridge in the first retracted position protrudes from the opening 16a of the apparatus main body 1A is defined as the first length (P1), and the length by which the second toner cartridge in the second retracted position protrudes from the opening 16a is defined as the second length (P2). In this case, it can be said that the first length is longer than the second length.

[0116] Compared with the toner cartridge 70k, the toner cartridges 70y to 70c with a smaller size are preferably designed such that the distance P2 by which they protrude outside the apparatus at the retracted position is shorter than the distance P1 by which the toner cartridge 70k protrudes outside the apparatus at the retracted position. This is for the following reasons. When the toner cartridge 70 is in the retracted position, at least a part of the toner cartridge 70 protrudes outside the rotary locus of the rotary main body 90 or outside the external surface of the apparatus main body 1A. At this time, the tray 80 is supported cantilevered by the rotary main body 90 and supports the weight of the toner cartridge 70. Therefore, reducing the distance P2 by which the toner cartridges 70y to 70c protrude outside the apparatus at the retracted position can reduce the load applied to the trays 80y to 80c and the guide portion 97 of the rotary main body 90 that supports the trays 80y to 80k. Further, since the toner cartridges 70y to 70c are smaller in size than the toner cartridge 70k, even if the distance P2 is made shorter than the distance P1, the workability of replacing the cartridges with respect to the trays 80y to 80c can be maintained.

[0117] (Tray Arrangement within the Rotary Unit) The arrangement of the trays 80y to 80k within the rotary main body 90 will be described with reference to FIGS. 8, 9, and 10. FIG. 8 is a perspective view showing the arrangement of the trays 80y to 80k within the rotary main body 90. FIG. 9 is a cross-sectional view showing the arrangement of the trays 80y to 80k within the rotary main body 90. FIG. 10 is a view showing the member arrangement at one end side in the Y direction of the trays 80y to 80k. Note that FIG. 9 shows a cross-section of the rotary main body 90 in a virtual plane perpendicular to the rotation axis 90C of the rotary main body 90. Also, the upper half of FIG. 10 is a view of the rotary main body 90 and the trays 80m, 80k in FIG. 8 as seen from the upper right side (+Z side) of FIG. 8, and the lower half of FIG. 10 is a view of the rotary main body 90 and the trays 80c, 80y in FIG. 8 as seen from the left side (-X side) of FIG. 8.

[0118] As shown in FIG. 8, each of the trays 80y to 80k is provided with cartridge holding portions 81y to 81k and guided portions 82y to 82k.

[0119] The toner cartridges 70y-70k are attached to the cartridge holding portions 81y-81k, respectively. Each of the cartridge holding portions 81y-81k accommodates at least a portion of the toner cartridges 70y-70k attached thereto.

[0120] The guided portions 82y-82k are provided on both ends of the trays 80y-80k that sandwich the cartridge holding portions 81y-81k in the Y direction. The guided portions 82y-82k are elongated members that extend in a direction perpendicular to the rotation axis of the rotary body 90.

[0121] In this embodiment, a reinforcing rib 82k1 is formed on a part of the guided portion 82k in the moving direction Dk of the tray 80k, and a reinforcing rib 82m1 is formed on a part of the guided portion 82m in the moving direction Dm of the tray 80m (see also Figs. 11(a) and 11(b)). The reinforcing ribs 82k1 and 82m1 are rib shapes (protrusions) that protrude outward in the Y direction from the guided portions 82k and 82m provided at both ends of the trays 80k and 80m in the Y direction and extend in the moving directions Dk and Dm of the trays 80k and 80m. The reinforcing ribs 82k1 and 82m1 improve the rigidity of the guided portions 82k and 82m.

[0122] In this embodiment, the length of the reinforcing ribs 82m1 and 82k1 is limited to avoid the guided portions 82y and 82c, but if there is no interference with the guided portions 82y and 82c, the reinforcing ribs 82m1 and 82k1 may be provided over the entire length of the guided portions 82m and 82k. Reinforcing ribs may be added to the guided portions 82y and 82c. If the rigidity of the guided portions 82m and 82k is sufficient, the reinforcing ribs 82m1 and 82k1 may not be provided.

[0123] Rack portions 83y to 83k (rack gears) are formed on the guided portions 82y to 82k. Pinion gears 94y to 94k are rotatably held within the rotary body 90. The pinion gears 94y to 94k are engaged with the rack portions 83y to 83k, respectively, so as to be capable of transmitting driving force.

[0124] The rack portions 83y to 83k and the pinion gears 94y to 94k are part of the moving devices 85y to 85k configured to move the toner cartridges 70y to 70k from the mounting positions to the retracted positions. Also, it can be said that the rack portions 83y to 83k and the pinion gears 94y to 94k are part of the driven devices driven by the driving device 98 of the apparatus main body 1A. The pinion gears 94y to 94k can be said to be rotating bodies (rotating members) that move the trays 80y to 80k relative to the rotary main body 90 by rotating.

[0125] The pinion gears 94y to 94k and the rack portions 83y to 83k function as driven parts for the moving devices 85y to 85k of the rotary main body 90 to receive driving force from the driving device 98 of the apparatus main body 1A. The pinion gear 94k and the rack portion 83k are examples of a first pinion gear and a first rack gear that constitute at least part of the first driven part provided in the first moving device. The pinion gear 94m and the rack portion 83m are examples of a second pinion gear and a second rack gear that constitute at least part of the second driven part provided in the second moving device.

[0126] The rotary main body 90 has guide portions 97 (see FIGS. 7(a) and 7(b)) that engage with the respective guided portions 82y to 82k. FIG. 7(a) shows the guide portion 97 (97k) that engages with the guided portion 82k of the tray 80k, and FIG. 7(b) shows the guide portion 97 (97m) that engages with the guided portion 82m of the tray 80m. Similar guide portions are provided on the rotary main body 90 for engaging with the guided portions 82y and 82c of the trays 80y and 80c. Also, in FIGS. 7(a) and 7(b), the guide portion 97 provided on one side (+Y side) of the rotary main body 90 in the Y direction is shown, but similar guide portions 97 are also provided on the other side (-Y side) of the rotary main body 90 in the Y direction.

[0127] When the tray 80 moves between the storage position and the take-out position, in at least a part of the moving range, the guide part 97 maintains the engaged state with the guided part 82 and guides the moving direction of the tray 80. In this embodiment, in the entire moving range between the storage position and the take-out position of the tray 80k, the guide part 97k maintains the engaged state with the guided part 82k. Also, in this embodiment, in the entire moving range between the storage position and the take-out position of the tray 80m, the guide part 97m maintains the engaged state with the guided part 82m.

[0128] Also, as shown in FIGS. 8 and 9, in the rotary main body 90, four trays 80y to 80k are arranged so as to overlap each other, as will be specifically described below.

[0129] When the pinion gears 94y to 94k rotate, the rack parts 83y to 83k and the trays 80y to 80k move with respect to the rotary main body 90. As shown in FIG. 9, with respect to the rotary main body 90, the moving directions of the four trays 80y to 80k are arranged to be rotated by 90 degrees each. Therefore, the tray 80y and the tray 80c, and the tray 80m and the tray 80k are each held slidably in substantially the same direction (parallel direction). The moving directions of the respective trays 80y to 80k during such sliding movement are restricted by the engagement between the aforementioned guided parts 82y to 82k and the guide part 97.

[0130] Note that the trays 80y to 80k move outside the machine through the opening 16a. When each of the trays 80y to 80k moves outside the machine from the opening 16a, the moving directions of the respective trays are substantially the same direction (parallel).

[0131] As shown in FIG. 9, with respect to the moving direction Dk of the tray 80k, the range where the tray 80k is arranged is arranged so as to overlap the range where the tray 80y is arranged and the range where the tray 80c is arranged. Also, with respect to the moving direction Dk of the tray 80k, the range where the tray 80k is arranged overlaps the rotation axis 90C of the rotary body 90. That is, it can be said that the toner cartridge 70k held by the cartridge holding portion 81k of the tray 80k overlaps the rotation axis 90C of the rotary body 90 (FIG. 4(b)).

[0132] On the other hand, with respect to the moving direction Dm of the tray 80m, the range where the tray 80m is arranged is arranged offset so as not to overlap the range where the tray 80y is arranged and the range where the tray 80c is arranged. Further, with respect to the moving direction Dy of the tray 80y, the range where the tray 80y is arranged is arranged offset so as not to overlap the range where the tray 80m is arranged and the range where the tray 80k is arranged. Similarly, with respect to the moving direction Dc of the tray 80c, the range where the tray 80c is arranged is arranged offset so as not to overlap the range where the tray 80m is arranged and the range where the tray 80k is arranged.

[0133] The positional relationship between the trays 80 can also be expressed as follows. When viewed in the moving direction Dy of the tray 80y, the tray 80y and the tray 80k overlap, but the tray 80y and the tray 80m do not overlap. When viewed in the moving direction Dm of the tray 80m, the tray 80m and the tray 80k overlap, but the tray 80m and the trays 80y, 80c do not overlap. When viewed in the moving direction Dc of the tray 80c, the tray 80c and the tray 80k overlap, but the tray 80c and the tray 80m do not overlap.

[0134] Here, for two elements (members, parts, units, etc.) to overlap when viewed in a specific direction means that when each element is perpendicularly projected onto a virtual plane perpendicular to the said direction, the projection area of one element and the projection area of the other element at least partially overlap.

[0135] As shown in FIGS. 8 and 10, in the direction of the rotation axis 90C (Y direction), the range where the rack portion 83m and the guided portion 82m are arranged and the range where the rack portion 83k and the guided portion 82k are arranged overlap at least partially. That is, in this embodiment, it can be said that in the rotary rotation axis direction (Y direction), the range where the first rack gear (rack portion 83k) is arranged and the range where the second rack gear (rack portion 83m) is arranged overlap at least partially. Therefore, compared with the arrangement where the rack portion 83m and the guided portion 82m do not overlap with the rack portion 83k and the guided portion 82k, in the Y direction, the rack portions 83m, 83k and the guided portions 82m, 82k can be arranged in a space-saving manner.

[0136] In the direction of the rotation axis 90C (Y direction), the range where the rack portion 83y and the guided portion 82y are arranged and the range where the rack portion 83c and the guided portion 82c are arranged overlap at least partially. That is, in this embodiment, it can be said that in the rotary rotation axis direction (Y direction), the range where the third rack gear (rack portion 83y) is arranged and the range where the fourth rack gear (rack portion 83c) is arranged overlap at least partially. Therefore, compared with the arrangement where the rack portion 83y and the guided portion 82y do not overlap with the rack portion 83c and the guided portion 82c, in the Y direction, the rack portions 83y, 83c and the guided portions 82y, 82c can be arranged in a space-saving manner.

[0137] Here, the meshing position of the rack portion 83 with the pinion gear 94 will be described with reference to FIG. 10. The upper half of FIG. 10 shows the meshing position of the rack portion 83k and the pinion gear 94k. The lower half of FIG. 10 shows the meshing position of the rack portion 83y and the pinion gear 94y.

[0138] Regarding the direction (Y direction) of the rotation axis 90C of the rotary body 90, in the region Y1 in the figure, the driving force transmitted from the motor M2 (Fig. 2) as the driving source to the transmission device described later is transmitted to the pinion gears 94y to 94k. In the region Y2 in the figure regarding the Y direction, the pinion gear 94k is in mesh with the rack portion 83k so as to enable driving transmission. In the region Y3 in the figure regarding the Y direction, the pinion gear 94y is in mesh with the rack portion 83y so as to enable driving transmission. Note that the rack portion 83m is in mesh with the pinion gear 94m (Fig. 8) in the region Y2 in the same manner as the rack portion 83k so as to enable driving transmission. The rack portion 83c is in mesh with the pinion gear 94c (Fig. 8) in the region Y3 in the same manner as the rack portion 83y so as to enable driving transmission.

[0139] Here, the region Y2 and the region Y3 are at different positions in the Y direction (shifted in the Y direction). Also, the region Y1 is at a different position in the Y direction from both the region Y2 and the region Y3. That is, the region Y1 is shifted in the Y direction with respect to the region Y2 and the region Y3.

[0140] Furthermore, with the toner cartridges 70y, 70c in the mounted positions, regarding the moving direction (moving direction Dy of the tray 80y) of the rack portion 83y, the range where the rack portion 83y is arranged and the range where the rack portion 83c is arranged overlap at least partially. In this embodiment, since the moving directions Dy, Dc of the trays 80y, 80c are substantially in the same direction (parallel), regarding the moving direction Dc of the tray 80c as well, the range where the rack portion 83y is arranged and the range where the rack portion 83c is arranged overlap at least partially. Therefore, with the toner cartridges 70y, 70c in the mounted positions, regarding the direction orthogonal to the moving directions Dy, Dc of the rack portions 83y, 83c (the left - right direction in Fig. 8), the tooth surfaces of the rack portion 83y and the rack portion 83c face each other.

[0141] Furthermore, with the toner cartridges 70m and 70k in the mounting positions, regarding the moving direction of the rack portion 83m (the moving direction Dm of the tray 80m), the range where the rack portion 83m is disposed and the range where the rack portion 83k is disposed overlap at least partially. In this embodiment, since the moving directions Dm and Dk of the trays 80m and 80k are substantially in the same direction (parallel), regarding the moving direction Dk of the tray 80k as well, the range where the rack portion 83m is disposed and the range where the rack portion 83k is disposed overlap at least partially. Therefore, with the toner cartridges 70m and 70k in the mounting positions, regarding the direction orthogonal to the moving directions Dm and Dk of the rack portions 83m and 83k (the vertical direction in FIG. 8), the tooth surfaces of the rack portion 83m and the rack portion 83k face each other.

[0142] Also, as shown in FIG. 12(a) described later, when viewed in the direction of the rotation axis 90C (Y direction), the rack portion 83y overlaps the rack portion 83m and the rack portion 83k. When viewed in the direction of the rotation axis 90C (Y direction), the rack portion 83m overlaps the rack portion 83y and the rack portion 83c. When viewed in the direction of the rotation axis 90C (Y direction), the rack portion 83c overlaps the rack portion 83m and the rack portion 83k. When viewed in the direction of the rotation axis 90C (Y direction), the rack portion 83k overlaps the rack portion 83y and the rack portion 83c. In other words, regarding the rotary rotation axis direction (Y direction), it can be said that the range where the first rack gear (rack portion 83k) is disposed and the range where the second rack gear (rack portion 83y) is disposed do not overlap. Also, when viewed in the rotary rotation axis direction (Y direction), with the first toner cartridge 70k in the first mounting position and the second toner cartridge 70y in the second mounting position, it can be said that the first rack gear (rack portion 83k) and the second rack gear (rack portion 83y) overlap.

[0143] Thus, since the positions where the rack portions 83k and 83m are disposed are different from the positions where the rack portions 83y and 83c are disposed in the Y direction, the rack portions 83y and 83c and the rack portions 83m and 83k can be arranged to overlap when viewed in the Y direction.

[0144] This enables space savings in the four tray arrangements within the rotary body 90, and realizes miniaturization in the radial direction of the rotary body 90. That is, if we try to arrange the racks 83 so that they do not overlap when viewed in the Y direction while keeping the movement distances of the respective trays 80y to 80k the same as in this embodiment, the area required for the arrangement of the four racks when viewed in the Y direction becomes larger. Compared with such a configuration, by arranging a plurality of racks 83 with their positions shifted in the Y direction and overlapping the racks 83 with each other when viewed in the Y direction, the arrangement area of the racks 83 when viewed in the Y direction can be reduced.

[0145] Also, in this embodiment, the four racks 83y to 83k are divided into two sets of two and arranged with their positions shifted in the Y direction. That is, regarding the rotational axis direction (Y direction) of the rotary, it can be said that the ranges where the first rack gear and the second rack gear are arranged overlap, and the ranges where the third rack gear and the fourth rack gear are arranged overlap. Also, regarding the Y direction, it can be said that the range where the first rack gear and the second rack gear are arranged and the range where the third rack gear and the fourth rack gear are arranged are arranged so as not to overlap. Thereby, compared with the case where each of the four racks 83y to 83k is shifted in the Y direction, miniaturization of the rotary body 90 in the Y direction is possible.

[0146] (Tray movement configuration) The configuration regarding the movement of the trays 80y to 80k arranged in the rotary body 90 will be described with reference to FIGS. 11(a, b) and 12(a, b). FIGS. 11(a, b) are perspective views showing the configuration regarding the movement of the tray 80k. FIGS. 12(a, b) are cross-sectional views showing the configuration regarding the movement of the tray 80k.

[0147] In this embodiment, trays 80y to 80k are all driven by the driving force of motor M2 being transmitted to pinion gears 94y to 94k by driving racks 15L and 15R as transmission devices. Here, the configuration of moving tray 80k with respect to rotary body 90 will be described. The configurations of moving trays 80y to 80c with respect to rotary body 90 are substantially the same as the configuration of moving tray 80k, and thus the description thereof will be omitted.

[0148] FIG. 11(a) shows a state where tray 80k is inside rotary body 90 (that is, a state where toner cartridge 70k is mounted on developing unit 50k). That is, FIG. 11(a) shows a state where tray 80k is at the storage position, corresponding to a state where toner cartridge 70k is at the mounting position with respect to developing frame 53k (FIG. 4(a)). FIG. 11(b) shows a state where tray 80k is slid and moved outside rotary body 90. That is, FIG. 11(b) shows a state where tray 80k is at the extraction position, corresponding to a state where toner cartridge 70k is at the retracted position with respect to developing frame 53k (FIG. 4(b)).

[0149] The apparatus main body 1A of this embodiment has driving racks 15L and 15R as driving gears for driving pinion gear 94. Each driving rack 15 is driven by motor M2 via a driving transmission mechanism (not shown).

[0150] As described above, two rack portions 83k are formed at both ends of tray 80k in the Y direction. Two pinion gears 94k and two driving racks 15L and 15R are respectively arranged at positions corresponding to the rack portions 83k at both ends. That is, the apparatus main body 1A of this embodiment has driving racks 15L and 15R as the first driving gear and the second driving gear. It can be said that driving rack 15L is an example of the first driving gear, and driving rack 15R is an example of the second driving gear. However, these numberings are merely used for convenience in description and can be appropriately interchanged in principle. When it is not necessary to distinguish between driving racks 15L and 15R, they are denoted as "driving rack 15".

[0151] The rack portion 83 of this embodiment is configured as a pair of rack gears, and the pinion gear 94 of this embodiment is configured as a pair of pinion gears. In this embodiment, the pair of rack gears and the pair of pinion gears are arranged on one end side and the other end side of the support member (tray 80) in the Y direction, but they may be arranged at other positions. The rack portion 83k and the pinion gear 94k of the moving device 85k corresponding to the tray 80k can be said to be examples of a first pair of rack gears and a first pair of pinion gears, respectively. The rack portions 83y to 83c and the pinion gears 94y to 94c of the moving devices 85y to 85c corresponding to any one of the other trays 80y to 80c can be said to be examples of a second pair of rack gears and a second pair of pinion gears, respectively.

[0152] One of the pair of rack gears meshes with one of the pair of pinion gears, and the other of the pair of rack gears meshes with the other of the pair of pinion gears. At least one of the pair of pinion gears is driven by the drive rack 15L as a first drive rack. In this embodiment, both of the pair of pinion gears are simultaneously driven by the drive racks 15L and 15R as the first drive rack and the second drive rack. As a result, the rotation of the tray 80 is less likely to occur, and the stable movement of the toner cartridge 70 becomes possible.

[0153] Note that the tray 80 may have a configuration in which it has one rack portion 83 and is moved by one drive rack 15 via one pinion gear 94.

[0154] The tray 80k is held so as to be slidable in a direction parallel to the guided portion 82k (i.e., the moving direction Dk) with respect to the rotary main body 90. The drive rack 15 is held so as to be slidable in a direction intersecting the moving direction Dk of the tray 80k with respect to the apparatus main body 1A. The drive rack 15 is configured to slide (reciprocate) with respect to the apparatus main body 1A in a first direction (vertically upward in this embodiment) and a second direction opposite to the first direction (vertically downward in this embodiment). That is, the moving direction of the drive rack 15 in this embodiment is a direction (preferably a direction perpendicular) intersecting both the moving direction Dk of the tray 80k and the direction (Y direction) of the rotation axis 90C of the rotary main body 90.

[0155] Using FIGS. 11(a) and 11(b), the tray movement operation for sliding the tray 80k between the storage position and the take-out position will be described. The tray movement operation of the tray 80k is performed by the motor M2 (FIG. 2), a drive transmission mechanism (not shown), the drive rack 15, the pinion gear 94k, and the rack portion 83k.

[0156] First, the tray movement operation (tray pulling-out operation) when removing the toner cartridge 70k from the rotary main body 90 will be described. Before the start of the tray pulling-out operation, the drive rack 15 is positioned below the position where it meshes with the pinion gear 94k (FIG. 11(a)). Also, as described above, in the replacement operation of the toner cartridge 70k, the rotary main body 90 takes the replacement posture of the toner cartridge 70k (FIG. 4(b)).

[0157] When the tray pulling-out operation is started, the drive rack 15 is slid upward on the apparatus main body 1A by the driving force of the motor M2. During the movement of the drive rack 15, it meshes with the pinion gear 94k, and the pinion gear 94k is rotationally driven.

[0158] As shown in FIG. 11(b), when the pinion gear 94k is rotationally driven in the direction of the arrow in the figure, a driving force is input to the rack portion 83k that meshes with the pinion gear 94k. As a result, the tray 80k is pushed out of the machine and moves from the storage position to the take-out position with respect to the rotary main body 90. At this time, the moving direction of the tray 80k is guided in a predetermined moving direction Dk by the engagement between the guided portion 82k and the guide portion 97k (FIG. 7(a)) of the rotary main body 90. As a result of the tray 80k moving from the storage position to the take-out position, the toner cartridge 70k is moved from the mounting position to the retracted position with respect to the developing unit 50k.

[0159] In a state where the tray 80k is in the take-out position and the toner cartridge 70k is in the retracted position, the user can attach and detach the toner cartridge 70k with respect to the tray 80k.

[0160] When attaching the toner cartridge 70 to the rotary main body 90, the tray movement operations (tray insertion operation, tray insertion operation) are performed in the reverse process of the tray extraction operation. Before the tray insertion operation starts, the drive rack 15 is positioned above the position where it meshes with the pinion gear 94k. For example, when the user operates a predetermined operation unit, the tray insertion operation starts. When the tray insertion operation starts, the drive rack 15 is slid downward by the driving force of the motor M2. Here, the rotation direction of the motor M2 in the tray insertion operation is opposite to that in the tray extraction operation. As the drive rack 15 moves, it meshes with the pinion gear 94k, and the pinion gear 94k is rotationally driven.

[0161] When the pinion gear 94k is rotationally driven in the direction opposite to the arrow in FIG. 11(b), a driving force is input to the rack portion 83k that meshes with the pinion gear 94k. As a result, the tray 80k is drawn into the machine and moves from the take-out position to the storage position with respect to the rotary main body 90. The moving direction of the tray 80k is guided in the moving direction Dk (opposite to the arrow in FIG. 11(b)) by the engagement between the guided portion 82k and the guide portion 97k (FIG. 7(a)) of the rotary main body 90. As a result of the tray 80k moving from the take-out position to the storage position, the toner cartridge 70k is moved from the retracted position to the mounted position with respect to the developing unit 50k.

[0162] The movement of the black tray 80k and toner cartridge 70k has been described above. The movement of the other trays 80y to 80c and toner cartridges 70y to 70c is also performed by the same mechanism. That is, in the replacement posture of each toner cartridge, the drive rack 15 transmits the drive to the pinion gears 94y to 94c.

[0163] A drive device 98 for driving the moving device 85 provided on the rotary main body 90 is constituted by the motor M2 provided on the apparatus main body 1A, the drive rack 15 (15L, 15R), and a transmission device including a drive transmission mechanism.

[0164] As described above, in the present embodiment, a plurality of moving devices 85k to 85y corresponding to a plurality of toner cartridges 70k to 70y are arranged on the rotary main body 90. The drive device 98 of the device main body 1A is a common drive device that drives a plurality of moving devices 85k to 85y (a plurality of driven devices) of the rotary main body 90.

[0165] Also, in the present embodiment, the drive target of the drive device 98 is switched by the rotation of the rotary main body 90. In other words, the drive device of the present embodiment includes a drive rack 15 as a transmission member that transmits the driving force of the drive source. The drive device can take a state in which the transmission member is in driving engagement with the first driven part (pinion gear 94k) and a state in which the transmission member is in driving engagement with the second driven part (pinion gear 94m). Further, the drive device can take a state in which the transmission member is disengaged from the first driven part and the second driven part.

[0166] As described above, the pinion gears 94y to 94k are held by the rotary main body 90. Therefore, when the rotary main body 90 rotates, it is preferable that the meshing between the pinion gears 94y to 94k and the drive rack 15 is released.

[0167] FIG. 12(a) shows a state where the tray 80k is inside the rotary main body 90 (in the storage position). FIG. 12(b) shows a state where the tray 80k has moved outside the rotary main body 90 (moved to the take-out position).

[0168] As shown in FIG. 12(a), when the tray 80k is inside the rotary main body 90, the drive rack 15 is located at the lower part inside the device main body 1A. At this time, the drive rack 15 is retracted from the pinion gear 94k. Therefore, the drive rack 15 does not interfere, and the rotary main body 90 can be rotated. More specifically, the drive rack 15 can be retracted outside the rotation locus of the rotary main body 90 indicated by the dotted line in FIGS. 12(a) and 12(b).

[0169] As described above, by rotationally driving the motor M2 in the forward and reverse directions, the tray 80 attached to the rotary body 90 can be moved with respect to the rotary body 90 from the storage position to the take-out position and also from the take-out position to the storage position. That is, the drive device of the present embodiment can not only drive each moving device of the rotary so that the toner cartridge moves from the mounting position to the retracted position, but also drive each moving device so that the toner cartridge moves from the retracted position to the mounting position.

[0170] Here, as described above, in the present embodiment, the moving amount of the tray 80 at the time of toner cartridge replacement is changed according to the size of the toner cartridge 70. Specifically, as shown in FIGS. 7(a, b), the moving distance L1 when the black tray 80k moves from the storage position to the take-out position is longer than the moving distance L2 when the other trays 80y to 80c move from the storage position to the take-out position.

[0171] Therefore, in the present embodiment, when moving the toner cartridges 70y to 70k from the mounting position to the retracted position, the value obtained by dividing the speed of the rack portion 83k by the speed of the drive rack 15 is larger than the value obtained by dividing the speed of the rack portions 83y to 83c by the speed of the drive rack 15.

[0172] For example, as shown in FIG. 10, the pinion gear 94y is a stepped gear, and the pitch circle radius of the small-diameter gear 942 that meshes with the rack portion 83y is made smaller than the pitch circle radius of the large-diameter gear 941 that meshes with the drive rack 15. The pinion gears 94m and 94c are also similar stepped gears. On the other hand, the pinion gear 94k has the same pitch circle radius for the portion that meshes with the drive rack 15 and the portion that meshes with the rack portion 83k. At this time, the pitch circle radius of the pinion gear 94k can be made the same as the pitch circle radius of the large-diameter gear 941 of the pinion gears 94y to 94c. According to this configuration, even if the moving distance of the drive rack 15 is the same, the moving distance of the rack portion 83k can be made larger than the moving distances of the other rack portions 83y to 83c. That is, the moving distance L1 when the black tray 80k moves from the storage position to the take-out position can be made longer than the moving distance L2 when the other trays 80y to 80c move from the storage position to the take-out position.

[0173] Also, by making the pinion gears 94y to 94c stepped gears, it is possible to make the moving distance L1 of the tray 80k larger than the moving distances L2 of the other trays 80y to 80c while the pinion gears 94y to 94k are configured to receive driving force from the same drive rack 15.

[0174] Note that instead of (or in combination with) the configuration in which the pinion gears 94y to 94c are stepped gears, the pinion gear 94k may be a stepped gear. In this case, the portion of the pinion gear 94k that meshes with the drive rack 15 may be a small-diameter gear, and the portion of the pinion gear 94k that meshes with the rack portion 83k may be a large-diameter gear having a pitch circle radius larger than that of the small-diameter gear. Also, the stepped gear is an example of a speed reduction mechanism, and it may be replaced with a known speed reduction mechanism that makes the moving amount of the member on the output side (tray 80 side) smaller than the moving amount of the member on the input side (drive source side).

[0175] Also, the moving amount of the drive rack 15 when the toner cartridge 70k moves from the mounting position to the retracted position may be made larger than the moving amount of the drive rack 15 when the toner cartridges 70y to 70c move from the mounting position to the retracted position.

[0176] Incidentally, the shorter the distance that the toner cartridge 70 moves from the mounting position to the retracted position, the shorter the movement time of the toner cartridge 70 can be, and the shorter the time that the user has to wait for the movement of the toner cartridge 70 can be. If the configuration is such that the amount of movement of the drive rack 15 with respect to the toner cartridge 70k is larger than the amount of movement of the drive rack 15 with respect to the toner cartridges 70y to 70c as described above, the time that the user has to wait for the movement of the toner cartridges 70y to 70c can be shortened.

[0177] With the configuration shown above, the movement distance L1 can be made longer than the movement distance L2. These configurations can also be used in combination.

[0178] (Modification example) Although the configuration in which the driven part has the pinion gear 94 that meshes with both the drive rack 15 and the rack part 83 has been described, the driven part may have a gear that meshes with the drive rack 15 and a gear that meshes with the rack part 83.

[0179] Also, the configuration of the moving device 85 that moves the tray 80 is not limited to the so-called rack and pinion configuration. For example, a member corresponding to the pinion gear 94 may be replaced with a roller that rotates under the drive of the motor M2, and the tray 80 may be moved by the friction between the roller and the tray 80.

[0180] Also, when using a roller that rotates under the drive of the motor M2, the roller may be brought into contact with the toner cartridge 70. In this case, the toner cartridges 70y to 70k can be made directly detachable from the rotary body 90 without going through the trays 80y to 80k. In this case, the moving device 85 is constituted by a roller. Furthermore, in this case, the rotary assembly 90A can be said to have the rotary body 90 and the toner cartridges 70y to 70k.

[0181] <Prevention of toner backflow from the developing unit to the toner cartridge> As the rotary assembly 90A rotates, the receiving opening (development opening) 53b may be positioned above the discharge opening 71b. For example, when the toner cartridge 70 is attached to the rotary main body 90 and the rotary main body 90 assumes the replacement posture (attachment / detachment posture), the receiving opening 53b is positioned above the discharge opening 71b. When the receiving opening 53b is positioned above the discharge opening 71b, it is preferable to suppress the backflow of toner from the developing unit 50 to the toner cartridge 70.

[0182] Hereinafter, with reference to FIGS. 13 and 14, a configuration for suppressing the backflow of toner from the developing unit 50 to the toner cartridge 70 will be described. In the following description, it is assumed that the toner cartridge 70 is attached to the rotary main body 90.

[0183] FIGS. 13(a) and (b) are cross-sectional views of the toner cartridge 70 and the developing unit 50 according to the present embodiment. FIGS. 13(a) and (b) are cross-sectional views taken in a direction perpendicular to the Y direction as viewed in the Y direction.

[0184] As shown in FIGS. 13(a) and (b), the developing unit 50 has a cover (restricting portion, toner restricting portion) 54. The cover 54 is housed in the developing-side housing portion (receiving-side housing chamber, developing-side housing chamber) 53a. The cover 54 is movable with respect to the receiving opening 53b and is movable between a cover position covering the receiving opening 53b and a retracted position (cover retracted position) retracted from the cover position.

[0185] In this embodiment, the developing unit 50 has a connecting portion 55 that supports the cover 54. The connecting portion 55 is connected to the cover 54 and is movable relative to the receiving opening 53b. The connecting portion 55 and the cover 54 are configured to move integrally. When the connecting portion 55 is moved, the cover 54 is moved between the cover position and the cover retracted position. The connecting portion 55 includes a shaft (transmission portion) 55a, and the cover 54 is attached to the shaft 55a. The shaft 55a is swingable about the cover swing axis 55c, and when the shaft 55a swings, the cover 54 also swings about the cover swing axis 55c and moves between the cover position and the cover retracted position. Details of the configuration for moving the cover 54 will be described later.

[0186] As shown in FIG. 13(b), with the receiving opening 53b located above the discharge opening (discharge port) 71b, the cover 54 is in the cover position. At this time, the cover 54 covers the receiving opening 53b, and the toner accommodated in the developing side accommodating portion 53a is restricted from being discharged to the outside of the developing unit 50 through the receiving opening 53b. The posture of the rotary body 90 in which the receiving opening 53b is located above the discharge opening 71b and the cover 54 is in the cover position can be referred to as the cover posture (first posture).

[0187] FIG. 13(b) can be said to be a view showing a state in which the rotary body 90 takes the first posture with the toner cartridge 70 attached to the rotary body 90. In other words, FIG. 13(b) can be said to be a view showing a state in which the rotary assembly 90A takes the first posture.

[0188] As shown in FIG. 13(a), with the receiving opening 53b positioned below the discharging opening 71b, the cover 54 is located at a cover retracted position retracted from the cover position. At this time, a gap through which toner can pass is formed between the cover 54 and the receiving opening 53b. When the cover 54 is located at the cover retracted position, it is allowed for the toner discharged from the discharging opening 71b to enter the developing side housing portion 53a through the space between the cover 54 and the receiving opening 53b. The posture of the rotary main body 90 in which the receiving opening 53b is positioned below the discharging opening 71b and the cover 54 is located at the cover retracted position can be referred to as a cover retracted posture (second posture).

[0189] FIG. 13(a) can be said to be a view showing a state in which the rotary main body 90 takes the second posture with the toner cartridge 70 attached to the rotary main body 90. In other words, FIG. 13(a) can be said to be a view showing a state in which the rotary assembly 90A takes the second posture.

[0190] In this embodiment, when the rotary main body 90 is in the cover retracted posture, the self-weight of the cover 54 acts from the cover position toward the cover retracted position. Further, when the rotary main body 90 is in the cover posture, the self-weight of the cover 54 acts from the cover retracted position toward the cover position.

[0191] Note that when the cover 54 is located at the cover position, it is not necessary for the receiving opening 53b to be completely closed by the cover 54. That is, it is not necessary for the discharge of toner from the receiving opening 53b to be completely restricted by the cover 54. For example, a gap may be formed between the cover 54 and the receiving opening 53b when the cover 54 is located at the cover position. In this case, the size of the gap formed between the cover 54 and the receiving opening 53b is smaller when the cover 54 is at the cover position as compared with the state where the cover 54 is at the cover retracted position.

[0192] Also, in a state where the cover 54 is located at the cover position, the cover 54 may block the receiving opening 53b so that no gap is formed between the cover 54 and the receiving opening 53b. That is, the discharge of toner from the receiving opening 53b may be completely restricted.

[0193] FIG. 14 is a cross-sectional view of the rotary assembly 90A according to the present embodiment. FIG. 14 is a cross-sectional view of a cross-section perpendicular to the Y direction as viewed in the Y direction. In FIG. 14, a state where the developing unit 50 and the corresponding toner cartridge 70 are located at positions Tp1, Tp2, Tp3, and Tp4, respectively, is shown.

[0194] When the rotary main body 90 to which the toner cartridge 70 is attached is in the replacement posture, the developing unit 50 and the toner cartridge 70 are located at position TP1. At this time, the receiving opening 53b is located above the discharge opening 71b, and the cover 54 is located at the cover position. In this state, the backflow of toner from the developing unit 50 to the toner cartridge 70 is suppressed. Therefore, toner leakage when replacing the toner cartridge 70 is suppressed.

[0195] Also, the cover 54 suppresses the toner once discharged from the toner cartridge 70 from returning to the toner cartridge 70. Therefore, after using the toner cartridge 70, the amount of toner remaining inside the toner cartridge 70 can be reduced. In other words, more of the toner stored in the toner cartridge 70 can be used up.

[0196] In this embodiment, the rotary main body 90 to which the toner cartridge 70 is attached rotates clockwise when viewed in the Y direction, rotates in the order of positions TP2, TP3, and TP4 from position TP1, and returns to position TP1 again. When the developing unit 50 and the toner cartridge 70 are at position TP2, the receiving opening 53b and the discharging opening 71b are located below the rotation axis 90C, and the receiving opening 53b is aligned horizontally with the discharging opening 71b. When the developing unit 50 and the toner cartridge 70 are at position TP3, the receiving opening 53b is located below the discharging opening 71b. When the developing unit 50 and the toner cartridge 70 are at position TP4, the receiving opening 53b and the discharging opening 71b are located above the rotation axis 90C, and the receiving opening 53b is aligned horizontally with the discharging opening 71b.

[0197] In this example, when the developing unit 50 and the toner cartridge 70 are at position TP4 and at position TP2, the cover 54 is positioned at the cover position. When the developing unit 50 and the toner cartridge 70 move from position TP4 to position TP2 via position TP1, at least a part of the receiving opening 53b is located above the discharging opening 71b. In this example, due to the rotation of the rotary assembly 90A, while the developing unit 50 and the toner cartridge 70 move from position TP4 to position TP2 via position TP1, the cover 54 is positioned at the cover position.

[0198] On the other hand, when the developing unit 50 and the toner cartridge 70 are at position TP3, the cover 54 is positioned at the cover retracted position. In this example, the position where the developing roller 51 of the developing unit 50 faces the photosensitive drum 2 is downstream of position TP3 and upstream of position TP4. In other words, while the posture of the rotary main body 90 changes from the exchange posture to the developing posture, the rotary main body 90 takes the cover retracted posture, and the cover 54 is positioned at the cover retracted position. In this example, when the developing unit 50 is at the developing position, the receiving opening 53b is located below the discharging opening 71b, and the cover 54 is positioned at the cover retracted position.

[0199] When the rotary body 90 rotates, the cover 54 moves to the cover retracted position after the developing unit 50 and the toner cartridge 70 pass through the position TP2, and moves to the cover position before the developing unit 50 and the toner cartridge 70 reach the position TP4. As a result, in a state where at least a part of the receiving opening 53b is positioned above the discharge opening 71b, the cover 54 is positioned at the cover position, and the backflow of toner from the developing unit 50 to the toner cartridge 70 is more reliably suppressed.

[0200] <Movement of the cover> Using FIGS. 15, 16, 17, 18, and 19, the configuration of the cover 54 and the configuration for moving the cover 54 will be described.

[0201] FIGS. 15(a), (b), 16(a), and (b) are diagrams showing the configuration of the cover 54 and the connecting portion 55 according to the present embodiment. In FIGS. 15(a) and (b), the cover 54 is positioned at the cover retracted position. In FIGS. 16(a) and (b), the cover 54 is positioned at the cover position. FIGS. 15(a) and 16(a) are diagrams showing the inside of the developing unit 50. FIGS. 15(b) and 16(b) are perspective views of the rotary body 90 as viewed from the outside of the developing unit 50. FIGS. 17(a) and (b) are cross-sectional views of the developing unit 50.

[0202] As shown in FIGS. 15(a) and 16(a), in the present embodiment, the developing frame 51 is provided with a plurality of receiving openings 53b. Further, the developing unit 50 has a plurality of covers 54. In other words, the developing opening includes a plurality of receiving openings 53b, and the regulating portion (toner regulating portion) includes a plurality of covers 54. When the plurality of covers 54 are at the cover position, the plurality of covers 54 cover the plurality of receiving openings 53b, and when the plurality of covers 54 are at the cover retracted position, the toner discharged from the toner cartridge 70 is allowed to pass between the plurality of covers 54 and the plurality of receiving openings 53b and enter the developing side accommodating portion 53a.

[0203] Note that in this embodiment, the number of the receiving openings 53b is two, but the number of the receiving openings 53b may be one or more than two. The covers 54 are arranged corresponding to the respective receiving openings 53b. Therefore, the number of the covers 54 may be one or more than two.

[0204] As described above, the developing unit 50 includes the connecting portion 55. The connecting portion 55 includes a shaft 55a that is swingable around a cover swing axis 55c, and the cover 54 is attached to the shaft 55a. Hereinafter, the direction in which the cover swing axis 55c extends is referred to as the swing axis direction. In this embodiment, the swing axis direction is parallel to the direction of the rotation axis 90C.

[0205] In a direction orthogonal to the swing axis direction, the cover 54 is arranged at a position away from the cover swing axis 55c. More specifically, the shaft 55a is bent, and a portion overlapping the cover swing axis 55c and a portion away from the cover swing axis 55c are formed. The cover 54 is attached to the portion away from the cover swing axis 55c.

[0206] The connecting portion 55 includes a receiving portion (held portion) 55b attached to the shaft 55a. When the receiving portion 55b is moved, the cover 54 is moved between a cover position and a cover retracted position via the shaft 55a. As shown in FIGS. 17(a) and (b), the receiving portion 55b is attached to one end of the shaft 55a, and the other end of the shaft 55a is supported by the developing frame 53.

[0207] The receiving part 55b is rotatably supported by the developing frame body 53c and includes a protruding part (contact part, restricted part) 55b1. While the cover 54 is accommodated in the developing side accommodating part 53a, the protruding part 55b1 is located outside the developing side accommodating part 53a. In a direction orthogonal to the swinging axis direction, the protruding part 55b1 is arranged at a position away from the cover swinging axis 55c. When the protruding part 55b1 is moved, the cover 54 moves between the cover position and the cover retracted position. That is, it can be said that the protruding part 55b1 is connected to the cover 54 so that the cover 54 moves in conjunction with the protruding part 55b1. In this embodiment, the rotary main body 90 has a movement restricting part 56r facing the receiving part 55b.

[0208] As understood from FIGS. 15(b) and 16(b), the position of the protruding part 55b1 when the cover 54 is in the cover retracted position is farther from the rotation axis 90C of the rotary main body 90 than the position of the protruding part 55b1 when the cover 54 is in the cover position. That is, in a direction orthogonal to the rotation axis 90C, when the protruding part 55b1 moves in a direction away from the rotation axis 90C, the cover 54 moves from the cover position toward the cover retracted position. In a direction orthogonal to the rotation axis 90C, when the protruding part 55b1 moves in a direction approaching the rotation axis 90C, the cover 54 moves from the cover retracted position toward the cover position. In other words, when the protruding part 55b1 (see FIG. 16(b)) when the cover 54 is in the cover position is moved in a direction away from the rotation axis 90C, the cover 54 moves to the cover retracted position. When the protruding part 55b1 (see FIG. 15(b)) when the cover 54 is in the cover retracted position is moved in a direction approaching the rotation axis 90C, the cover 54 moves to the cover position.

[0209] The protruding part 55b1 is moved along with the rotation of the rotary main body 90. Hereinafter, the rotation of the rotary main body 90 and the movement of the protruding part 55b1 will be described.

[0210] Figs. 18(a), (b), and (c) are views showing a rotary holder 99 that supports a rotary body 90. Fig. 18(a) is a view of the rotary holder 99 seen in the Y direction, Fig. 18(b) is a view of the rotary holder 99 seen in the direction opposite to the Y direction, and Fig. 18(c) is a perspective view of the rotary holder 99.

[0211] Figs. 19(a), (b), and (c) are views showing the relationship between the rotation of the rotary body 90 and the movement of the protrusion 55b1 with respect to the rotary holder 99. Fig. 19(a) is a perspective view showing the rotary holder 99 and the protrusion 55b1, and Figs. 19(b) and 19(c) are side views of the rotary holder 99 and the rotary body 90. Figs. 19(b) and (c) are views of the rotary holder 99 and the rotary body 90 seen in the Y direction.

[0212] The apparatus main body 1A has a rotary holder (rotary connection member, rotary support member) 99. The rotary holder 99 has a rotary connection part (rotary support part) 99h. The rotary body 90 (rotary assembly 90A) is supported by the rotary connection part 99h so as to be rotatable around the rotation axis 90C. The rotary holder 99 is provided with a connection hole 99r.

[0213] The rotary holder 99 is swingable so that the rotation axis 90C of the rotary body 90 is displaced. More specifically, a swing axis 91 (Fig. 5) is inserted into the connection hole 99r. Thereby, the rotary holder 99 is swingably supported around the swing axis 91. When the rotary cams 90eL, 90eR (Fig. 5) come into contact with the roller 96, the rotary holder 99 swings around the swing axis 91. As a result, the rotary body 90 swings around the swing axis 91. In Fig. 19(b), the rotary body 90 is in the developing posture, and the rotation axis 90C of the rotary body 90 is at a position closer to the photosensitive drum 2. In Fig. 19(c), the rotary body 90 is in the replacement posture, and the rotation axis 90C of the rotary body 90 is at a position farther from the photosensitive drum 2.

[0214] The rotary holder 99 has surfaces 99sr, 99sc1, and 99sc2. In this embodiment, the surfaces 99sr, 99sc1, and 99sc2 have an arc shape centered on the rotation axis 90C. The length of the arc shape of the surface 99sc1 is longer than half of the circumference of a circle having the same radius as the radius of the arc shape of the surface 99sc1. The length of the arc shape of the surface 99sc2 is longer than half of the circumference of a circle having the same radius as the radius of the arc shape of the surface 99sc2.

[0215] When the rotary body 90 rotates with respect to the rotary holder 99, the protrusion 55b1 is displaced with respect to the surfaces 99sr, 99sc1, and 99sc2. Specifically, the protrusion 55b1 rotates around the centers of the arc shapes of the surfaces 99sr, 99s1, and 99s2, respectively. The surfaces 99sr, 99sc1, and 99sc2 form a guide portion for guiding the connecting portion 55. In other words, the guide portion for guiding the connecting portion 55 includes the surfaces 99sr, 99sc1, and 99sc2. The protrusion 55b1 as a part of the connecting portion 55 engages with the guide portion.

[0216] When the rotary body 90 rotates with respect to the rotary holder 99, the protrusion 55b1 passes through the portion indicated by the dotted line in Fig. 19(b). The position of the protrusion 55b1 in contact with the surface 99sr is farther from the rotation axis 90C than the position of the protrusion 55b1 in contact with the surface 99sc1. Also, the position of the protrusion 55b1 in contact with the surface 99sr is farther from the rotation axis 90C than the position of the protrusion 55b1 in contact with the surface 99sc2.

[0217] Each of the surfaces 99sr, 99sc1, and 99sc2 has a function as a holding portion for holding the cover 54 in the cover position or the cover retracted position. When the rotary body 90 rotates around the rotation axis 90C, the protrusion 55b1 is displaced with respect to the holding portion (surfaces 99sr, 99sc1, and 99sc2). When the rotary body 90 (rotary assembly 90A) rotates with respect to the rotary holder 99, the connecting portion 55 abuts against each of the surfaces 99sr, 99sc1, and 99sc2, so that the cover 54 is positioned in the cover position or the cover retracted position.

[0218] With the protrusion 55b1 as a part of the connecting portion 55 in contact with the surface 99sr, the cover 54 is positioned at the cover retracted position. The surface 99sr restricts the cover 54 from moving from the cover retracted position toward the cover position. More specifically, when the protrusion 55b1 is in contact with the surface 99sr and the cover 54 is at the cover retracted position, the surface 99sr is closer to the rotation axis 90C than the protrusion 55b1. That is, in the moving direction of the protrusion 55b1 when the cover 54 moves from the cover retracted position toward the cover position, the surface 99sr is located on the downstream side of the protrusion 55b1. Therefore, the movement of the protrusion 55b1 is restricted, and the cover 54 is restricted from moving from the cover retracted position toward the cover position.

[0219] In addition, when the connecting portion 55 moves in a direction away from the rotation axis 90 with the protrusion 55b1 of the connecting portion 55 in contact with the surface 99sr, the receiving portion 55b comes into contact with the movement restricting portion 56r. Therefore, the moving distance of the cover 54 in a direction away from the receiving opening 53b is restricted within a predetermined range.

[0220] With the protrusion 55b1 in contact with the surface 99sc1, the cover 54 is positioned at the cover position. The surface 99sc1 restricts the cover 54 from moving from the cover position toward the cover retracted position. More specifically, when the protrusion 55b1 is in contact with the surface 99sc1 and the cover 54 is at the cover position, the surface 99sc1 is farther from the rotation axis 90C than the protrusion 55b1. That is, in the moving direction of the protrusion 55b1 when the cover 54 moves from the cover position toward the cover retracted position, the surface 99sc1 is located on the downstream side of the protrusion 55b1. Therefore, the movement of the protrusion 55b1 is restricted, and the cover 54 is restricted from moving from the cover position toward the cover retracted position.

[0221] As described above, when the cover 54 is in the cover position, the passage of toner between the cover 54 and the receiving opening 53b may be completely restricted. In this case, for example, the cover 54 may have elasticity and may be deformed by coming into contact with the periphery of the receiving opening 53a in a state where the cover 54 is positioned at the cover position.

[0222] With the protruding portion 55b1 in contact with the surface 99sc2, the cover 54 is positioned at the cover position. With the protruding portion 55b1 of the connecting portion 55 in contact with the surface 99sc2, the movement of the connecting portion 55 in the direction approaching the rotation axis 90 is restricted.

[0223] When the size of the protruding portion 55b1 is smaller than the distance between the surfaces 99sc1 and 99sc2, the position of the cover 54 when the protruding portion 55b1 contacts the surface 99sc1 and the position of the cover 54 when the protruding portion 55b1 contacts the surface 99sc2 are not completely the same. However, in both the case where the protruding portion 55b1 contacts the surface 99sc1 and the case where it contacts the surface 99sc2, the discharge of toner from the receiving opening 53b is suppressed by the cover 54. Therefore, both the position of the cover 54 when the protruding portion 55b1 contacts the surface 99sc1 and the position of the cover 54 when the protruding portion 55b1 contacts the surface 99sc2 can be referred to as the cover position.

[0224] In this way, the surface (first restricting portion) 99sc1 is configured to restrict the movement of the cover 54 from the cover position toward the cover retracted position when the rotary main body 90 (rotary assembly 90A) is in the cover posture. Further, the surface (second restricting portion) 99sr is configured to restrict the movement of the cover 54 from the cover retracted position toward the cover position when the rotary main body 90 (rotary assembly 90A) is in the cover retracted posture.

[0225] When the rotary body 90 (rotary assembly 90A) rotates with respect to the rotary holder 99, the protrusion 55b1 is positioned upstream of the cover swing axis 55c. As a result, the protrusion 55b1 can move smoothly while sliding on the surfaces 99sr, 99sc1, and 99sc2.

[0226] After the rotary body 90 (rotary assembly 90A) rotates with respect to the rotary holder 99 and the developing unit 50 and the toner cartridge 70 pass through the position TP2 (see FIG. 14), the protrusion 55b1 abuts against the surface 99sr. As a result, the cover 54 is positioned at the cover retracted position. The surface 99sr can be referred to as a holding surface (second holding surface) that abuts against the protrusion 55b1 and holds the cover 54 at the cover retracted position. When the protrusion 55b1 abuts against the surface 99sr, the cover 54 is restricted from retracting from the cover retracted position. In the present embodiment, when the developing unit 50 is at the developing position, the protrusion 55b1 abuts against the surface 99sr. In a state where the cover 54 is positioned at the cover retracted position, toner discharged from the discharge opening 71b of the toner cartridge 70 is allowed to be supplied to the developing unit 50.

[0227] When the rotary body 90 (rotary assembly 90A) further rotates with respect to the rotary holder 99 from the state where the developing unit 50 is at the developing position, before the developing unit 50 and the toner cartridge 70 reach the position TP4 (see FIG. 14), the protrusion 55b1 separates from the surface 99sr.

[0228] After the protrusion 55b1 separates from the surface 99sr and before the developing unit 50 and the toner cartridge 70 reach the position TP4, the protrusion 55b1 enters the guide groove formed by the surfaces 99sc1 and 99sc2. In the present embodiment, the width of the guide groove is larger than that of the protrusion 55b1. The protrusion 55b1 that has entered the guide groove can abut against at least one of the surfaces 99sc1 and 99sc2. In a state where the protrusion 55b1 has entered the guide groove, the cover 54 is positioned at the cover position.

[0229] In this embodiment, when the rotary body 90 (rotary assembly 90A) is in the replacement posture, the protrusion 55b1 is in the state of entering the guide groove and can be in contact with at least one of the surface 99sc1 and the surface 99sc2. At least one of the surface 99sc1 and the surface 99sc2 can be called a holding surface (first holding surface) that contacts the protrusion 55b1 to hold the cover 54 in the cover position. By the protrusion 55b1 contacting at least one of the surface 99sc1 and the surface 99sc2, the cover 54 is restricted from retreating from the cover position. Therefore, when the rotary body 90 (rotary assembly 90A) is in the replacement posture, the cover 54 is positioned at the cover position. Further, when the rotary body 90 (rotary assembly 90A) is in the replacement posture, the cover 54 is restricted from moving to the cover retreat position. As a result, when the rotary body 90 (rotary assembly 90A) is in the replacement posture, the cover 54 can suppress the reverse flow of toner from the developing unit 50 to the toner cartridge 70.

[0230] <Example 2> With reference to FIGS. 20 and 21, a configuration for suppressing the reverse flow of toner from the developing unit 50 to the toner cartridge 70 according to Example 2 will be described. In Example 2, the same components as those described in Example 1 are denoted by the same reference numerals, and detailed descriptions are omitted in principle.

[0231] FIGS. 20(a), (b), (c) and FIGS. 21(a), (b), (c) are diagrams showing the configuration of the cover 154 as a restricting portion according to Example 2 and the connecting portion 155 connected to the cover 154. In FIGS. 21(a), (b), (c), the cover 154 is positioned at the cover position, and the cover 154 covers the receiving opening 53b. In FIGS. 20(a), (b), (c), the cover 154 is in the cover retreat position retreated from the cover position.

[0232] The developing unit 50 has a cover 154 as a regulating part (toner regulating part). The cover 154 is accommodated in the developing side accommodating part 53a. The cover 154 is movable with respect to the receiving opening 53b, and is movable between a cover position covering the receiving opening 53b and a cover retracted position retracted from the cover position.

[0233] In this embodiment, the developing unit 50 has a connecting part 155 that supports the cover 154. The connecting part 155 is connected to the cover 154 and is movable with respect to the receiving opening 53b. The connecting part 155 and the cover 154 are configured to move integrally. By moving the connecting part 155, the cover 154 is moved between the cover position and the cover retracted position. The connecting part 155 includes a shaft (transmission part) 155a, and the cover 154 is attached to the shaft 155a. The shaft 155a is swingable around a cover swing axis 155c, and by swinging the shaft 155a, the cover 154 moves linearly and moves between the cover position and the cover retracted position.

[0234] The cover 154 is provided with a hole 154a. When the cover 154 is in the cover position, the hole 154a does not overlap with the receiving opening 53b. When the cover 154 is in the cover retracted position, the hole 154a overlaps with the receiving opening 53b, and the toner discharged from the toner cartridge 70 can enter the receiving side accommodating part 53a via the receiving opening 53b and the hole 154a.

[0235] Note that, in the state where the cover 154 is in the cover position, it is not necessary for the receiving opening 53b to be completely closed by the cover 154. That is, it is not necessary for the discharge of toner from the receiving opening 53b to be completely restricted by the cover 154. Also, in the state where the cover 154 is in the cover position, the cover 154 may block the receiving opening 53b so that no gap is generated between the cover 154 and the receiving opening 53b. That is, the discharge of toner from the receiving opening 53b may be completely restricted.

[0236] In this embodiment, the developing frame 51 is provided with a plurality of receiving openings 53b. Further, the developing unit 50 has a plurality of covers 154. In other words, the developing opening includes the plurality of receiving openings 53b, and the regulating part (toner regulating part) includes the plurality of covers 154. When the plurality of covers 154 are in the cover position, the plurality of covers 154 cover the plurality of receiving openings 53b, and when the plurality of covers 154 are in the cover retracted position, the toner discharged from the toner cartridge 70 is allowed to enter the developing side accommodating portion 53a through the respective holes 154a of the plurality of covers 154 and the plurality of receiving openings 53b.

[0237] Note that, in this embodiment, the number of the receiving openings 53b is two, but the number of the receiving openings 53b may be one or more than two. The covers 154 are arranged corresponding to the respective receiving openings 53b. Therefore, the number of the covers 154 may be one or more than two.

[0238] As described above, the developing unit 50 includes a connecting portion 155. The connecting portion 155 includes a shaft 155a that is swingable around a cover swing axis 155c, and the cover 154 is attached to the shaft 155a. Hereinafter, the direction in which the cover swing axis 155c extends is referred to as the swing axis direction. In this embodiment, the swing axis direction is parallel to the direction of the rotation axis 90C.

[0239] In a direction orthogonal to the swing axis direction, the cover 154 is arranged at a position away from the cover swing axis 155c. More specifically, the shaft 155a is bent, and a portion overlapping the cover swing axis 155c and a portion away from the cover swing axis 155c are formed. The cover 154 is attached to the portion away from the cover swing axis 155c.

[0240] The connecting portion 155 includes a receiving portion (held portion) 155b attached to the shaft 155a. When the receiving portion 155b is moved, the cover 154 moves between the cover position and the cover retracted position via the shaft 155a. The receiving portion 155b is attached to one end of the shaft 155a, and the other end of the shaft 155a is supported by the developing frame 53.

[0241] The receiving portion 155b is rotatably supported by the developing frame 53c and includes a protrusion (contact portion, restricted portion) 155b1. While the cover 154 is housed in the developing side housing portion 53a, the protrusion 155b1 is positioned outside the developing side housing portion 53a. In a direction orthogonal to the rocking axis direction, the protrusion 155b1 is disposed at a position away from the cover rocking axis 155c. When the protrusion 155b1 is moved, the cover 154 moves between the cover position and the cover retracted position. That is, it can be said that the protrusion 155b1 is connected to the cover 154 so that the cover 154 moves in conjunction with the protrusion 155b1.

[0242] Also in this embodiment, as in Embodiment 1, when the protrusion 155b1 contacts the holding portion of the rotary holder 99, the cover 154 is moved between the cover position and the cover retracted position. That is, also in this embodiment, the rotary holder 99 has portions corresponding to the surfaces 99sr, 99sc1, and 99sc2 of Embodiment 1. The shape and arrangement of these portions can be appropriately changed so that the timing at which the cover 154 moves between the cover position and the cover retracted position is the same as that in Embodiment 1.

[0243] <Embodiment 3> With reference to FIGS. 22 and 23, a configuration for suppressing the backflow of toner from the developing unit 50 to the toner cartridge 70 according to Embodiment 3 will be described. In Embodiment 3, the same components as those in the configuration described in Embodiment 1 are denoted by the same reference numerals, and detailed descriptions are generally omitted.

[0244] Figs. 22(a) and 22(b) are cross-sectional views of the toner cartridge 70 and the developing unit 50 according to this embodiment. Figs. 22(a) and 22(b) are cross-sectional views of a cross-section in a direction perpendicular to the Y direction as viewed in the Y direction.

[0245] As shown in Figs. 22(a) and 22(b), the developing unit 50 has a cover 254 as a regulating part (toner regulating part). The cover 254 is housed in a developing-side housing part (receiving-side housing chamber, developing-side housing chamber) 53a. The cover 254 is movable between a cover position covering the receiving opening 53b as a developing opening and a cover retracted position retracted from the cover position. The cover 254 has a sheet part (cover main body) 254a and a weight 254b.

[0246] The sheet part 254a of the cover 254 includes one end fixed to the developing frame 53 and the other end opposite to the one end. When the cover 254 moves between the cover position and the cover retracted position, the sheet part 254a of the cover 254 deforms between the one end and the other end. Also, when viewed in the direction of the rotation axis 90C of the rotary main body 90, the other end is closer to the rotation axis 90C than the one end.

[0247] As shown in Fig. 22(b), the cover 254 is in the cover position with the receiving opening 53b located above the discharge opening (discharge port) 71b. At this time, the cover 254 covers the receiving opening 53b, and the toner housed in the developing-side housing part 53a is regulated from being discharged to the outside of the developing unit 50 through the receiving opening 53b. The posture of the rotary main body 90 in which the receiving opening 53b is located above the discharge opening 71b and the cover 254 is in the cover position can be called a cover posture (first posture).

[0248] As shown in Fig. 22(a), with the receiving opening 53b positioned below the discharge opening 71b, the cover 254 is located at the cover retracted position retracted from the cover position. At this time, a gap through which toner can pass is formed between the cover 254 and the receiving opening 53b for the toner discharged from the discharge opening 71b. When the cover 254 is located at the cover retracted position, it is allowed to pass through between the cover 254 and the receiving opening 53b and enter the developing side housing portion 53a. The posture of the rotary main body 90 in which the receiving opening 53b is positioned below the discharge opening 71b and the cover 254 is located at the cover retracted position can be referred to as the cover retracted posture (second posture).

[0249] In this embodiment, when the rotary main body 90 is in the cover retracted posture, the self-weight of the cover 254 acts from the cover position toward the cover retracted position. Further, when the rotary main body 90 is in the cover posture, the self-weight of the cover 254 acts from the cover retracted position toward the cover position. As the rotary main body 90 rotates, the direction in which the self-weight of the cover 254 acts changes. The cover 254 of this embodiment can move between the cover retracted position and the cover position due to the change in the direction in which the self-weight of the cover 254 acts. By the cover 254 having the weight 254b, the self-weight of the cover 254 increases. Therefore, the cover 254 is more likely to move by its own weight. Note that if the self-weight of the sheet portion 254a is heavy enough, the cover 254 does not need to have the weight 254b.

[0250] The cover 254 in this embodiment is configured to move between the cover position and the cover retracted position by its own weight.

[0251] In this embodiment, the sheet portion 254a is configured to be elastically deformable, and in the natural state of the sheet portion 254a (the state where the sheet 254a is not deformed), the cover 254 is positioned at the cover position. When the cover 254 moves from the cover position to the cover retracted position, the sheet portion 254a is deformed, so the cover 254 moves by its own weight against the restoring force of the sheet portion 254a. When the cover 254 moves from the cover retracted position to the cover position, the deformation of the sheet portion 254a is eliminated, so the cover 254 moves by the restoring force of the sheet portion 254a and its own weight.

[0252] Note that when the cover 254 moves from the cover retracted position to the cover position, the cover 254 may move by its own weight against the restoring force of the sheet portion 254a. In this case, when the cover 254 moves from the cover position to the cover retracted position, the cover 254 moves by the restoring force of the sheet portion 254a and its own weight.

[0253] Also, the cover body corresponding to the sheet portion 254a may be substantially non-deformable and supported movably with respect to the developing frame body 53. In this case, the cover 254 moves from the cover retracted position to the cover position by its own weight, and further moves from the cover position to the cover retracted position by its own weight.

[0254] Note that in the state where the cover 254 is positioned at the cover position, it is not necessary for the receiving opening 53b to be completely closed by the cover 254. That is, it is not necessary for the discharge of toner from the receiving opening 53b to be completely restricted by the cover 254. For example, a gap may be formed between the cover 254 and the receiving opening 53b in the state where the cover 254 is positioned at the cover position. In this case, the size of the gap formed between the cover 254 and the receiving opening 53b is smaller when the cover 254 is at the cover position than when the cover 254 is at the cover retracted position.

[0255] Also, in a state where the cover 254 is positioned at the cover position, the cover 254 may block the receiving opening 53b so that no gap is formed between the cover 254 and the receiving opening 53b. That is, the discharge of toner from the receiving opening 53b may be completely restricted.

[0256] FIG. 23 is a cross-sectional view of the rotary assembly 90A according to this embodiment. FIG. 23 is a cross-sectional view taken in a direction perpendicular to the Y direction as viewed in the Y direction. In FIG. 23, a state is shown in which the developing unit 50 and the corresponding toner cartridge 70 are positioned at positions Tp1, Tp2, Tp3, and Tp4, respectively.

[0257] When the rotary body 90 is in the replacement posture, the developing unit 50 and the toner cartridge 70 are positioned at position TP1. At this time, the receiving opening 53b is positioned above the discharge opening 71b, and the cover 254 is positioned at the cover position. In this state, the backflow of toner from the developing unit 50 to the toner cartridge 70 is suppressed. Therefore, toner leakage when replacing the toner cartridge 70 is suppressed. Also, the toner once discharged from the toner cartridge 70 is suppressed from returning to the toner cartridge 70. Therefore, after using the toner cartridge 70, the amount of toner remaining inside the toner cartridge 70 can be reduced. In other words, more of the toner stored in the toner cartridge 70 is used up.

[0258] In this embodiment, the rotary main body 90 rotates clockwise when viewed in the Y direction, rotates in the order of positions TP2, TP3, TP4 from position TP1, and returns to position TP1 again. When the developing unit 50 and the toner cartridge 70 are at position TP2, the receiving opening 53b and the discharging opening 71b are located below the rotation axis 90C, and the receiving opening 53b is horizontally aligned with the discharging opening 71b. When the developing unit 50 and the toner cartridge 70 are at position TP3, the receiving opening 53b is located below the discharging opening 71b. When the developing unit 50 and the toner cartridge 70 are at position TP4, the receiving opening 53b and the discharging opening 71b are located above the rotation axis 90C, and the receiving opening 53b is horizontally aligned with the discharging opening 71b.

[0259] In this example, when the developing unit 50 and the toner cartridge 70 are at position TP4 and at position TP2, the cover 254 is located at the cover position. When the developing unit 50 and the toner cartridge 70 move from position TP4 to position TP2 via position TP1, at least a part of the receiving opening 53b is located above the discharging opening 71b. In this example, due to the rotation of the rotary assembly 90A, while the developing unit 50 and the toner cartridge 70 move from position TP4 to position TP2 via position TP1, the cover 254 is located at the cover position.

[0260] On the other hand, when the developing unit 50 and the toner cartridge 70 are at position TP3, the cover 254 is located at the cover retracted position. The position where the developing roller 51 of the developing unit 50 faces the photosensitive drum 2 is downstream of position TP3 and upstream of position TP4. In other words, while the posture of the rotary main body 90 changes from the exchanging posture to the developing posture, the rotary main body 90 takes the cover retracted posture, and the cover 254 is located at the cover retracted position. In this example, when the developing unit 50 is at the developing position, the receiving opening 53b is located below the discharging opening 71b, and the cover 254 is located at the cover retracted position.

[0261] When the rotary body 90 rotates, the cover 254 moves to the cover retracted position after the developing unit 50 and the toner cartridge 70 pass through the position TP2, and moves to the cover position before the developing unit 50 and the toner cartridge 70 reach the position TP4. As a result, in a state where at least a part of the receiving opening 53b is positioned above the discharge opening 71b, the cover 254 is positioned at the cover position, and backflow of toner from the developing unit 50 to the toner cartridge 70 is more reliably suppressed.

[0262] In the present embodiment, the developing frame 51 is provided with a plurality of receiving openings 53b. Further, the developing unit 50 has a plurality of covers 254. In other words, the developing opening includes a plurality of receiving openings 53b, and the regulating unit (toner regulating unit) includes a plurality of covers 254. When the plurality of covers 254 are at the cover positions, the plurality of covers 254 cover the plurality of receiving openings 53b, and when the plurality of covers 254 are at the cover retracted positions, toner discharged from the toner cartridge 70 is allowed to enter the developing side housing portion 53a through the gaps between the plurality of covers 254 and the plurality of receiving openings 53b.

[0263] In the present embodiment, the number of the receiving openings 53b is two, but the number of the receiving openings 53b may be one or more than two. The covers 254 are arranged corresponding to the respective receiving openings 53b. Therefore, the number of the covers 254 may be one or more than two.

[0264] As described above, according to the present invention, backflow of toner from the developing unit 50 to the toner cartridge 70 is suppressed.

Explanation of Signs

[0265] 16 Main body frame (frame) 16a Opening 51 Developing roller 51k Developing roller, first developing roller 51y, 51m, 51c Developing roller, second developing roller 53a Housing portion, first housing portion, second housing portion (developing side housing portion) 53k housing frame, first housing frame (development frame) 53y, 53m, 53c housing frames, second housing frame (development frame) 70k toner cartridge, first toner cartridge 70y, 70m, 70c toner cartridges, second toner cartridge 54, 154, 254 covers (restriction part, toner restriction part) 99 rotary holder

Claims

1. A developing unit having a developing roller, a developing frame body provided with a receiving-side accommodation chamber and a developing opening communicating with the receiving-side accommodation chamber, a cover position covering the developing opening, and a toner regulating portion movable between the cover position and a retracted position retracted from the cover position, and a contact portion connected to the toner regulating portion; A rotary member that supports the developing unit and is rotatable about a rotational axis extending in the axial direction; A holding portion capable of contacting the contact portion; A toner cartridge detachable from the rotary member, the toner cartridge having: (i) A supply-side accommodation chamber for accommodating toner; and (ii) A discharge port communicating with the supply-side accommodation chamber; And a frame body including the above; And having; When the rotary member rotates, the contact portion is movable relative to the holding portion; When the rotary member is in the first posture, the developing opening is positioned above the discharge port, and the holding portion and the contact portion are in contact with each other such that the toner regulating portion is positioned at the cover position; When the rotary member is in the second posture, the developing opening is positioned below the discharge port, the toner regulating portion is positioned at the retracted position, and toner discharged from the discharge port is allowed to enter the receiving-side accommodation chamber. An image forming apparatus characterized by the above.

2. The image forming apparatus according to claim 1, further comprising a rotary holder that supports the rotary member and has the holding portion.

3. The image forming apparatus according to claim 2, wherein the rotary holder is configured to be swingable such that the rotational axis of the rotary member is displaced.

4. The image forming apparatus according to claim 1, wherein when the rotary member is in the first posture, the holding portion is configured to restrict the toner regulating portion from moving from the cover position to the retracted position.

5. The image forming apparatus according to claim 1, wherein when the rotary member is in the second posture, the holding portion and the contact portion are in contact with each other such that the toner regulating portion is positioned at the retracted position.

6. The image forming apparatus according to claim 5, wherein when the rotary member is in the second posture, the holding portion is configured to restrict the toner regulating portion from moving from the retracted position to the cover position.

7. The image forming apparatus according to any one of claims 1 to 6, wherein the holding portion forms a groove into which the contact portion is inserted.

8. The image forming apparatus according to any one of claims 1 to 6, wherein the toner regulating portion is swingable between the cover position and the retracted position.

9. The image forming apparatus according to any one of claims 1 to 6, wherein the contact portion is located outside the receiving side housing chamber.

10. The developing opening includes a plurality of openings, The toner regulating portion includes a plurality of covers. When the toner regulating portion is in the cover position, the plurality of covers cover the plurality of openings. When the toner regulating portion is in the retracted position, toner discharged from the toner cartridge is allowed to enter the receiving side housing chamber. The image forming apparatus according to any one of claims 1 to 6, characterized in that.

11. The image forming apparatus according to any one of claims 1 to 6, wherein the toner regulating portion is housed in the receiving side housing chamber.

12. The image forming apparatus according to any one of claims 1 to 6, wherein when the rotary is in an exchange posture allowing attachment and detachment of the toner cartridge, the developing opening is located above the discharge port, and the toner regulating portion is located at the cover position.

13. Further having a photosensitive drum, When the rotary is in the developing posture, the developing roller faces the photosensitive drum, The image forming apparatus according to claim 12, wherein the rotary takes the second posture while the posture of the rotary changes from the exchange posture to the developing posture.

14. A developing unit having a developing roller, a developing frame body having a receiving side housing chamber and a developing opening communicating with the receiving side housing chamber, a toner regulating portion movable between a cover position covering the developing opening and a retracted position retracted from the cover position, A rotary that supports the developing unit and is rotatable around a rotation axis extending in the axial direction, A toner cartridge detachable from the rotary, A frame body including (i) a supply side housing chamber for housing toner and (ii) a discharge port communicating with the supply side housing chamber, Having a toner cartridge, Having, The toner regulating portion is configured to move between the cover position and the retracted position by the weight of the toner regulating portion, When the rotary unit with the toner cartridge mounted thereon is in the first posture, the developing opening is positioned above the discharge port, and the self-weight of the toner regulating unit acts from the retracted position toward the cover position so that the toner regulating unit is positioned at the cover position. When the rotary unit with the toner cartridge mounted thereon is in the second posture, the developing opening is positioned below the discharge port, and the self-weight of the toner regulating unit acts from the cover position toward the retracted position so that the toner regulating unit is positioned at the retracted position, and toner discharged from the discharge port is allowed to enter the receiving-side storage chamber. The toner regulating unit includes one end fixed to the developing frame body and the other end opposite to the one end, and when the toner regulating unit moves between the cover position and the retracted position, the toner regulating unit is elastically deformable between the one end and the other end. An image forming apparatus characterized by the above.

15. The image forming apparatus according to claim 14, wherein, when viewed in the axial direction, the other end is closer to the rotation axis than the one end.

16. The developing opening includes a plurality of openings. The toner regulating unit includes a plurality of covers. When the toner regulating unit is at the cover position, the plurality of covers cover the plurality of openings. When the toner regulating unit is at the retracted position, toner discharged from the toner cartridge is allowed to enter the receiving-side storage chamber. The image forming apparatus according to claim 14 or 15, characterized by the above.

17. The image forming apparatus according to claim 14 or 15, characterized in that the toner regulating unit is accommodated in the receiving-side storage chamber.

18. The image forming apparatus according to claim 14 or 15, characterized in that when the rotary unit is in the replacement posture allowing attachment and detachment of the toner cartridge, the developing opening is positioned above the discharge port, and the toner regulating unit is positioned at the cover position.

19. Further comprising a photosensitive drum. When the rotary unit is in the developing posture, the developing roller faces the photosensitive drum. The image forming apparatus according to claim 18, characterized in that the rotary unit takes the second posture while the posture of the rotary unit changes from the replacement posture to the developing posture.

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