JP4360367B2 - Image forming apparatus using process cartridge - Google Patents

Description

The present invention relates to an image forming apparatus using the process cartridge.

  In an image forming apparatus used for a copying machine, a printer, or the like, a process cartridge including the element is detachably attached to the image forming apparatus for replacement or repair of an element necessary for an image forming process, jamming, or the like. ing. Such a process cartridge needs to be securely mounted and positioned on the image forming apparatus so as not to cause a malfunction.

For this reason, in Patent Document 1, if the process cartridge is not completely pushed into the main body, a part of the holding member that holds the process cartridge protrudes from the opening of the handle so that the process cartridge reaches a predetermined position. There is a proposal that can determine whether or not it has been pushed. Patent Document 2 proposes a mechanism in which when a cover is closed, a stopper mechanism provided on the cover presses and fixes the process unit in conjunction with the cover. Patent Document 3 proposes a process unit that is positioned by rotating a process unit that is detachable in a direction in which it is in contact with or away from the photoreceptor.
Patent No. 2555753 Japanese Utility Model Publication No. 6-31473 No. 6-8595

  However, in the process cartridge positioning that has been proposed in the past, if the half-locked state or the half-inserted state is left, or if the rotation operation is neglected, re-operation is required, or the pressing and fixing mechanism is There was a problem of being complicated.

The present invention has been made in view of the above problems, the positioning of the body easily performed with a simple mechanism, and a process cartridge that can be attached to reliably be left half-locked state and insufficiently inserted body It is an object of the present invention to provide an image forming apparatus to be used.

As means for solving the above problems, the present invention provides:
An image is formed by using a process cartridge having an element necessary for image formation that can be attached to and detached from a rotating rack that is rotated and provided in the main body of the image forming apparatus, and an element of the process cartridge and other elements necessary for an image forming process. In an image forming apparatus comprising image forming means for forming
The process cartridge is
A unit section having a current image roller as a necessary elements to the image forming process,
The process cartridge moves to the image forming apparatus body in the direction of the rotation axis of the rotating rack in conjunction with the process cartridge moving around the rotation axis of the rotating rack in the image forming apparatus body by the rotation of the rotating rack. The first pressing portion is pressed by a first pressing portion provided in the image forming apparatus main body in the mounting direction and positions the process cartridge at a first predetermined position of the image forming apparatus main body.

Thus, when the process cartridge is moved an image forming apparatus main body, the first pressed portion of the process cartridge in the first pressing portion of the image forming apparatus main body is positioned by being pressed, mounting of the process unit is not Even if it is complete, it is securely mounted in place.

A positioning portion that engages with an engaged portion provided in the image forming apparatus main body and positions the unit portion at a predetermined mounting position of the image forming apparatus main body ;
It is preferable that the positioning portion has the first pressed portion.

In conjunction with opening and closing of the cover of the image forming apparatus main body, wherein the rotation axis direction is a by the process cartridge carousel in the direction of attaching to the image forming apparatus main body, is pressed by the second pressing portion provided on the cover, the It is preferable to further include a second pressed portion that positions the process cartridge at a second predetermined position of the image forming apparatus main body.

When the process cartridge moves in the image forming apparatus main body to the third predetermined position, the image forming apparatus main body is provided in the direction of the rotation axis of the rotating rack and in the direction in which the process cartridge is attached to the image forming apparatus main body. It is preferable to further include a third pressed portion that is pressed by the three pressing portions and positions the process cartridge at the third predetermined position.

  The first pressed part and the second pressed part are preferably the same part.

It is preferable that the first pressed portion and the second pressed portion are not pressed by the first pressed portion and the second pressed portion when the process cartridge is completely attached to the image forming apparatus main body .

As apparent from the above description, according to the present invention, when the process cartridge is moved an image forming apparatus main body, the first pressed portion of the process cartridge is pressed by the first pressing portion of the image forming apparatus main body Therefore, even if the process unit is not completely mounted, it is securely mounted at a predetermined position.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is an overall configuration diagram of a color printer 10 to which the present invention is applied. The color printer 10 includes a developing unit 20, a photoreceptor unit 30, a laser print head 40, an intermediate transfer unit 50, and a fixing unit 60.

  The developing unit 20 has a rotating rack 22 that is driven to rotate in the direction of arrow a. The rotating rack 22 holds four developing devices 24Y, 24M, 24C, and 24K side by side in the circumferential direction. Each of the developing devices 24Y, 24M, 24C, and 24K stores yellow, magenta, cyan, and black toners. The developing devices 24Y, 24M, 24C, and 24K have developing rollers 26Y, 26M, 26C, and 26K that convey the toner held on the outer peripheral surface while rotating.

  The photoreceptor unit 30 has a photoreceptor drum 32 that is rotationally driven in the direction of arrow b. The photosensitive drum 32 is opposed to the developing rollers 26Y, 26M, 26C, and 26K of the developing devices 24Y, 24M, 24C, and 24K that have reached the developing position by the rotation of the rotating rack 22. In FIG. 1, the position where the developing unit 24Y is located is the developing position. Around the photosensitive drum 32, a charging charger 34 for uniformly charging the surface of the photosensitive drum 32 and a cleaner 36 for removing toner remaining on the surface of the photosensitive drum 32 after the primary transfer are disposed.

  The laser print head 40 irradiates the surface of the uniformly charged photoreceptor drum 32 with a laser beam 42 in accordance with image information input from the outside. As a result, an electrostatic latent image for each color toner image is formed on the surface of the photosensitive drum 32.

  The intermediate transfer unit 50 includes an intermediate transfer belt 56 that is looped around the four rollers 51, 52, 53, and 54 and is driven to rotate in the direction of arrow c. A primary transfer roller 58 is provided adjacent to the roller 54, and the intermediate transfer belt 56 faces the photosensitive drum 32 in the vicinity of the primary transfer roller 58. Further, the intermediate transfer belt 56 is opposed to the secondary transfer roller 59 at a portion supported by the roller 51. The facing portion between the secondary transfer roller 59 and the intermediate transfer belt 56 is an image forming portion A. A cleaner 57 that removes toner remaining on the surface of the intermediate transfer belt 56 after the secondary transfer is disposed on the outer surface of the intermediate transfer belt 56. Note that the intermediate transfer member is not limited to a belt shape, and may have another shape, for example, a drum shape.

  The fixing unit 60 includes a fixing device 62 and two discharge roller pairs 64 and 66 constituting a discharge unit. The sheet on which the image has been fixed by passing through the fixing device 62 is discharged onto the discharge tray 68 by the rotation of the discharge roller pair 64 and 66. In addition, the discharge unit may be configured with one roller pair or a belt pair.

  A paper feed cassette 70 serving as a paper feed unit is disposed below the color printer 10. In the paper feed cassette 70, sheets S such as recording paper are stacked and accommodated. The sheets S are sent out one by one in order from the uppermost one by the rotation of the paper feed roller 70.

  A sheet conveying path 74 is generally formed extending from the sheet feeding cassette 70 in the vertical direction. The sheet conveyance path 74 extends from the paper feed cassette 70 to the discharge roller pair 64 and 66 through the image forming unit A and the fixing device 62. The sheet S sent out from the paper feed cassette 70 is transported upward in the sheet transport path 74 by the respective transport roller pairs 76, 78, 80, and 82 that rotate.

  In the space between the sheet conveyance path 74 and the substantially flat side wall 12 of the printer main body, the sheet on which the image is formed on one side by the image forming unit A is temporarily stopped in the state shown in FIG. A refeed path 86 for refeeding the image forming unit A in a state where the front and back sides are reversed is provided.

  The upper part of the refeed path 86 extends to the inside of the fixing unit 60 and joins the sheet conveyance path 74 before the discharge roller pair 64. Further, the lower part of the refeed path 86 joins the sheet conveyance path 74 before the conveyance roller pair 78.

  Referring again to FIG. 1, a manual feed tray 96 is attached to the outside of the side wall 12 of the printer body. The manual feed tray 96 can be opened and closed by rotating about a shaft 97, and the sheet S is manually set in the opened state (the state shown in FIG. 1). The sheets S set on the manual feed tray 96 are sent one by one from the uppermost one to the sheet conveyance path 74 by the rotation of the paper feed roller 98.

  Since the developing units 24Y, 24M, 24C, and 24K are detachable from the printer main body, they are hereinafter referred to as a toner cartridge 200 (one form of the process cartridge of the present invention).

  First, the structure on the printer body side for mounting and positioning the toner cartridge 200 on the printer body will be described. As shown in FIG. 2, the front wall 14 of the main body has an opening 101 for taking out and inserting the toner cartridge 200 and an opening 102 for taking out and inserting the photosensitive unit 30 and the intermediate transfer unit 50. Is formed. As shown in FIG. 3, two arc-shaped ribs 104 and 105 having radii r1 and r2 around the shaft hole 103 that supports the rotating rack 22 are provided on the back of the front wall 14 (the first press according to the present invention). Corresponding to the portion). The upstream end portions of the ribs 104 and 105 with respect to the rotational direction a of the carousel 22 are inclined surfaces 104a and 105a. Further, on the downstream side of the ribs 104 and 105 with respect to the rotation direction of the rotating rack 22, the pressing lever 106 (the first embodiment of the present invention) is located at a radius r3 (r1> r2> r3) from the shaft hole 103 of the rotating rack 22. 3 corresponds to the pressing portion.) Is rotatably attached by the shaft 107. The pressing lever 106 is urged inward from the front wall 14 by a spring 108, and the tip thereof is in contact with an inverted U-shaped stopper 109.

  A cover 110 is provided outside the front wall 14 of the main body so as to cover the openings 101 and 102. As shown in FIG. 2, a protrusion 111 that presses the toner cartridge 200 inserted into the opening 101 when the cover 110 is closed (corresponding to a second pressing portion of the present invention) is provided inside the cover 110. Is provided.

  As shown in FIG. 4, the rotating rack 22 includes a rotating shaft 121, a circular end plate 122 provided at one end of the rotating shaft 121, and four wing plates 123 arranged around the rotating shaft 121. It is configured as an integral part and can be rotated as a whole around the axis of the rotating shaft 121. In a region surrounded by the two blades 123 of the end plate 122, a rotation shaft portion 124 made of a pin is provided so as to protrude in parallel to the rotation shaft 121. A first positioning recess 125, a second positioning recess 126, and a letter-shaped notch 127 are formed on the end face of each vane plate 123 in order from the outside toward the inside. The first positioning recess 125 of a certain blade 123 is positioned with the second positioning recess 126 of the blade 123 adjacent to the rotation direction of the rotating rack 22 and the positioning portion of the toner cartridge 200 inserted between them. Engaging portion).

  A first guide piece 128 extending in parallel with the rotating shaft 121 is formed on the outermost edge of one surface of the blade plate 123, and the other surface is located on the inner side of the first guide piece 128, Similarly, a second guide piece 129 extending in parallel with the rotation shaft 121 is formed. A first guide piece 128 of a blade plate 123 and a second guide piece 129 of the blade plate 123 adjacent to each other in the rotation direction of the rotating rack 22 constitute a guide portion of the toner cartridge 200 inserted therebetween. . Each blade 123 has a positioning lever 130, a first pressing lever 131, and a second pressing lever 132 inside the second guide piece 129 so that the blades 123 can rotate around shafts 133, 134, and 135, respectively. As shown in FIG. 13 (A), it is biased toward the second guide piece 129 by springs 136, 137, and 138.

  Next, the structure of the toner cartridge 200 itself will be described. As illustrated in FIG. 5, the toner cartridge 200 includes a unit portion 201, a positioning portion 202, a holding portion 203, a restriction release mechanism 204, and a protective cover 205.

  As shown in FIG. 6, the unit unit 201 includes a toner tank 25 and a developing roller 26 as elements necessary for the image forming process. The toner tank 25 is formed of an elongated container and stores toner of a predetermined color. The toner can be replenished from a replenishing port 27 provided at one end of the toner tank 25. The developing roller 26 is rotatably provided so that a part of the developing roller 26 is exposed at the opening 28 of the toner tank 25, and holds the toner in the toner tank 25 on the outer peripheral surface. Rollers 206 are provided at both ends of the developing roller 26. These rollers 206 are in pressure contact with the photosensitive drum 32 at the development position, so that the gap between the developing roller 26 and the photosensitive drum 32 is maintained with high accuracy to maintain high image quality.

  A guide surface 207 and a guide projection 208 are formed on the outer surface of the toner tank 25 and guided by the first guide piece 128 and the second guide piece 129 of the rotating rack 22 when the toner cartridge 200 is mounted. A pressing piece 209 is formed in parallel with the protrusion 208. The pressing piece 209 is configured such that the first pressing lever 131 and the second pressing lever 132 of the rotating rack 22 are in pressure contact with each other. Further, as shown in FIG. 12, the pressing piece 209 is formed with a locking portion 210 where the positioning lever 130 of the rotating rack 22 is locked.

  On the end surface of the toner tank 25 on the replenishing port 27 side, there are a rotation shaft portion 211 constituting a holding portion 203 and a rotation range restriction protrusion 212 for restricting the rotation of the unit portion 201 with respect to the positioning portion 202 as will be described later. Is formed. A screw hole 213 is formed in the rotation shaft portion 211. Further, as shown in FIG. 5, a shaft hole 214 is formed on the end surface of the toner tank 25 opposite to the replenishing port 27 at a position corresponding to the rotation shaft portion 211. The shaft hole 214 is adapted to fit the rotating shaft portion 124 of the end plate 122 of the rotating rack 22.

  The positioning portion 202 has a substantially plate shape covering the end portion of the toner tank 25 on the replenishing port 27 side. A first positioning convex portion 215 and a second positioning convex portion 216 extending in the longitudinal direction of the toner tank 25 are formed on the inner surfaces of both end portions of the positioning portion 202. The first positioning convex portion 215 and the second positioning convex portion 216 (corresponding to the positioning portion of the present invention) are engaged with the first positioning concave portion 125 and the second positioning concave portion 126 of the rotating rack 22. Yes. A holding hole 217 is formed at a position corresponding to the rotation shaft portion 211 of the toner tank 25 substantially at the center of the positioning portion 202. On the inner surface of the positioning portion 202, a V-shaped restriction that engages a fan-shaped rotation range restriction rib 218 into which the rotation range restriction protrusion 212 of the toner tank 25 enters and a restriction release pin 228 of a restriction release mechanism 204 described later. Ribs 219 are formed. On the other hand, on the outer surface of the positioning portion 202, as shown in FIG. 5, a fan-shaped first step portion 220 having a predetermined width at the position of the outermost radius r1 from the center of the rotating shaft 121 of the carousel 22 (the first step 220 of the present invention). 1), and a sector-shaped second step portion 221 having a predetermined width at the positions of the radii r2 and r3 (corresponding to the first and third pressed portions of the present invention). And a third step portion 222 is formed on the inner side.

  The holding portion 203 includes a rotation shaft portion 211 of the toner tank 25 and a holding hole 217 of the positioning portion 202 into which the rotation shaft portion 211 is fitted, and the unit portion 201 is connected to the positioning portion 202. So that it can be pivoted. The positioning portion 202 is prevented from coming off by screwing a screw 223 into the screw hole 213 of the rotating shaft portion 211 through the holding hole 217. Further, the rotation of the unit portion 201 is restricted within a predetermined range by the rotation range restriction projection 212 of the toner tank 25 entering the rotation range restriction rib 218 of the positioning portion 202.

  The restriction release mechanism 204 includes a restriction release lever 225 provided in the toner tank 25 and a restriction rib 219 formed in the positioning portion 202. The restriction release lever 225 is provided at the end of the toner tank 25 on the supply port 27 side so as to be rotatable about a shaft 226. A protruding piece 227 that protrudes away from the positioning portion 202 is formed at one end of the limiting release lever 225, and a limiting release pin 228 that protrudes toward the positioning portion 202 is formed at the other end. The restriction release lever 225 is biased by a spring 229 in a direction in which the restriction release pin 228 engages with the restriction rib 219 of the positioning portion 202. The protrusion 227 of the restriction release lever 225 contacts the slope of the notch 127 of the blade 123 of the rotating rack 22 when the toner cartridge 200 is mounted, and rotates the restriction release lever 225 about the shaft 226 in the arrow direction. The restriction release pin 228 is moved away from the restriction rib 219.

  The protective cover 205 is formed in a plate shape that covers the developing roller 26 of the unit portion 201. The protective cover 205 extends from both ends thereof and extends from the first wire lever 231 fitted in the shaft holes 230 provided at both ends of the toner tank 25 and the end of the toner tank 25 on the supply port 27 side. 25, a covering position that covers the developing roller 26 by a second wire lever 233 that is fitted in a shaft hole 232 provided on the end surface on the supply port 27 side and is smaller than the first wire lever 231, and away from the developing roller 26 Thus, it can move substantially parallel to the retracted position where the developing roller 26 is exposed.

  The movement of the protective cover 205 is interlocked with the rotation of the restriction release lever 225 by an interlocking mechanism. The interlock mechanism includes a link lever 234 that is rotatably provided coaxially with the shaft hole 230 of the first wire lever 231, one end wound around the first wire lever 231, and the other end of the restriction release lever 225. The link wire 235 is wound around the restriction release pin 228. An engaging portion 236 for engaging the link wire 235 is formed on the shaft side of the link lever 234, and a hole 237 through which the second wire lever 233 passes is formed on the distal end side.

  Incidentally, in the color printer 10 of the present embodiment, as shown in FIG. 2, a toner collection box 300 is provided between the front wall 14 of the main body and the cover 110. As shown in FIGS. 7 and 8, the toner collection box 300 has a substantially rectangular shape and is partitioned by a partition wall 301 at an upper portion and a lower portion. Below the toner collection box 300 are a first receiving port 302 that receives residual toner that is scraped by the cleaner 36 of the photosensitive drum 32 and conveyed by a conveying screw (not shown), and a cleaner 57 of the intermediate transfer belt 56. And a second receiving port 303 that receives residual toner that is scraped off and conveyed by a conveying screw (not shown). In addition, the toner collection box 300 has an upper portion of a toner jet 304 and an exhaust port 305, and a filter 306 is filled therebetween. The smoke toner inlet 304 is connected to a suction box 308 through a suction duct 307. The suction box 308 is a rectangular elongated box and is installed along the photosensitive drum 32. The suction box 308 is formed with a plurality of suction ports 309 on the surface facing the photosensitive drum 32. The exhaust port 305 is connected to a fan provided on a rear wall (not shown) via an exhaust duct 310.

  The toner collection box 300 collects residual toner scraped by the cleaner 36 of the photosensitive drum 32 and the cleaner 57 of the intermediate transfer belt 56 in the lower portion of the toner collection box 300. Smoke toner generated in the development area enters the upper part of the toner collection box 300 along the suction airflow indicated by the arrow of the fan rotation, and is collected and collected by the filter 306 here. As described above, since the collection of the residual toner on the photosensitive drum 32 and the intermediate transfer belt 56 and the collection of the fumed toner in the development area can be performed by the same toner collection box 300, the collection operation is simple. Further, since the fuming toner in the development area can be removed by the suction airflow, image defects such as toner fog are reduced.

  Hereinafter, the attaching / detaching operation of the toner cartridge 200 in the color printer 10 having the above-described configuration will be described.

  In FIG. 9, when the developing roller 26 indicated by hatching is in the developing area, the toner cartridge 200 is displaced from the opening 101 and cannot be taken out. This is to prevent the roller 206 of the developing roller 26 in the developing region from being damaged by the shaking or impact when the toner cartridge 200 is attached or detached, or the photosensitive drum 32 from being damaged by the roller 206. Here, for example, in order to take out the toner cartridge 200 having the developing roller 26 indicated by the hatching for replenishing or repairing the toner, the cover 110 is opened and the rotating rack 22 is rotated in the direction of the arrow by a handle (not shown), The toner cartridge 200 is positioned in the opening 101 as shown in FIG. At this time, the developing roller 26 of the other toner cartridge 200 is separated from the photosensitive drum 32 and there is no fear of contact. Therefore, the corresponding toner cartridge 200 can be removed with peace of mind. A part of the toner cartridge 200 is exposed to the outside from the opening 101 by a drawing mechanism (not shown), and then the toner cartridge 200 can be pulled out in the axial direction of the rotating rack 22 and taken out.

  When the toner cartridge 200 is taken out, the protrusion 227 of the restriction release lever 225 shown in FIG. 6 is separated from the notch 127 of the blade 123 of the rotating rack 22, so that the restriction release lever 225 is moved by the biasing force of the spring 229. In the counterclockwise direction. As a result, the first wire lever 231 and the second wire lever 233 are rotated clockwise in FIG. 6 via the link lever 234 and the link wire 235, and the protective cover 205 is moved to the covering position. As a result, the developing roller 26 is protected, and the operator's hand and clothes are not contaminated by the toner held on the developing roller 26. Further, as the restriction release lever 225 is rotated in the counterclockwise direction in FIG. 6, the restriction release pin 228 engages with the restriction rib 219 of the positioning portion 202, so that the positioning portion 202 rotates around the holding portion 203. Is regulated. As a result, the toner cartridge 200 after removal is in a state in which the unit portion 201 and the positioning portion 202 are relatively fixed, and there is no backlash.

  Next, in order to mount the toner cartridge 200 that has been replenished or repaired, or a new toner cartridge 200, the cover 110 is opened, and a handle (not shown) is turned so that the empty storage portion of the rotating rack 22 is opened. To be located. Subsequently, as shown in FIG. 2, the tip of the unit unit 201 is inserted into the opening 101 with the positioning unit 202 side of the toner cartridge 200 facing forward. At this time, since the guide surface 207 and the guide projection 208 of the unit part 201 are guided by the first guide piece 128 and the second guide piece 129 of the carousel 22, respectively, the unit part 201 is accommodated in the carousel 22 smoothly and reliably. . Here, even when the toner cartridge 200 is in a half-inserted state, the protrusion 111 of the cover 110 presses the outer surface of the positioning portion 202 of the toner cartridge 200 by closing the cover 110 as shown in FIG. The cartridge 200 is inserted into the rotating rack 22 (see FIGS. 11A and 11B).

  The state in which the toner cartridge 200 is inserted in this manner is in the first positioning state (corresponding to the second predetermined position of the present invention) as shown in FIG. In this first positioning state, in the toner cartridge 200, the rotating shaft portion 124 of the rotating rack 22 is slightly engaged with the shaft hole 214 of the unit portion 201, and the first positioning convex portion 215 and the first positioning convex portion 215 of the positioning portion 202 are engaged. The two positioning projections 216 are slightly engaged with the first positioning recess 125 and the second positioning recess 126 of the rotating rack 22. Further, the positioning lever 130 of the rotating rack 22 is not yet locked with the locking portion 210 of the toner cartridge 200. As described above, since the rotation of the positioning unit 202 around the holding unit 203 is restricted and the unit unit 201 and the positioning unit 202 are relatively fixed, the positioning unit of the toner cartridge 200 is fixed. The first positioning convex portion 215 and the second positioning convex portion 216 of 202 enter the first positioning concave portion 125 and the second positioning concave portion 126 of the rotating rack 22 reliably without shifting.

  When the toner cartridge 200 is inserted into the first positioning state, the protruding piece 227 of the restriction release lever 225 shown in FIG. 6 is pressed against the inclined surface of the notch 127 of the blade plate 123 of the rotating rack 22. The restriction release lever 225 rotates against the urging force of the spring 229. As a result, the first wire lever 231 and the second wire lever 233 rotate via the link lever 234 and the link wire 235, and the protective cover 205 moves to the open position. As a result, the developing roller 26 is exposed as shown in FIG.

  Further, as the restriction release lever 225 rotates, the restriction release pin 228 is detached from the restriction rib 219 of the positioning part 202, so that the rotation around the holding part 203 of the positioning part 202 is released. As a result, the toner cartridge 200 inserted in the first positioning state can be rotated by the unit portion 201 using the holding hole 217 of the positioning portion 202 and the rotating shaft portion 124 of the rotating rack 22 as fulcrums. At this time, the rotation range of the unit portion 201 is restricted to about ± 3 ° by the rotation range restriction protrusion 212 of the unit portion 201 coming into contact with the rotation range restriction rib 218 of the positioning portion 202.

  When the rotating rack 22 is rotated in the direction of the arrow by a handle (not shown) from the first positioning state, the first step portion 220 and the second step portion 221 of the positioning portion 202 of the toner cartridge 200 are sequentially placed on the rib 104 of the front wall 14. As a result, the toner cartridge 200 is further pushed in the axial direction of the rotating rack 22 (see FIGS. 11C and 11D), and corresponds to the second positioning state (corresponding to the first predetermined position of the present invention). .) In this second positioning state, the positioning lever 130 of the rotating rack 22 has not yet been locked with the locking portion 210 of the toner cartridge 200.

  When the rotating rack 22 is further rotated in the direction of the arrow from the second positioning state, the second step portion 221 (or the third step portion 222) of the positioning portion 202 of the toner cartridge 200 is pressed by the lever 106 of the front wall 14. As a result, the toner cartridge 200 is further pushed in the axial direction of the rotating rack 22 (see FIG. 11E), and is in a final positioning state (corresponding to the third predetermined position of the present invention). In this final positioning state, as shown in FIG. 13B through FIG. 12, in the toner cartridge 200, the rotating shaft portion 124 of the rotating rack 22 is completely engaged with the shaft hole 214 of the unit portion 201, The first positioning convex portion 215 and the second positioning convex portion 216 of the positioning portion 202 are completely engaged with the first positioning concave portion 125 and the second positioning concave portion 126 of the rotating rack 22. The positioning lever 130 of the rotating rack 22 is locked with the locking portion 210 of the toner cartridge 200 and is prevented from coming off.

  In this final positioning state, the positioning portion 202 of the toner cartridge 200 is separated from the ribs 104 and 105 of the front wall 14, so that the rotation of the rotating rack 22 is not hindered. In the final positioning state, the positioning lever 130, the first pressing lever 131, and the second pressing lever 132 of the rotating rack 22 press the unit portion 201 of the toner cartridge 200 by the urging force of the springs 136, 137, and 138. The piece 209 is pressed. As a result, as shown in FIG. 14, the unit portion 201 that can rotate around the holding portion 203 is urged in the rotation direction indicated by the arrow around the holding portion 203. Therefore, when the developing roller 26 of the toner cartridge 200 comes to the developing position facing the photosensitive drum 32, the roller 206 of the developing roller 26 comes into contact with the photosensitive drum 32, and the biasing force of the springs 136, 137, and 138 is exerted. It is pushed down against. As a result, a pressure contact force between the photosensitive drum 32 and 206 is generated, the gap between the developing roller 26 and the photosensitive drum 32 is maintained with high accuracy, and high image quality is achieved.

  In the embodiment described above, the toner cartridge 200 of the developing unit 20 has been described as the process cartridge of the present invention. However, the present invention is not limited to this, and the photoreceptor unit 30, the intermediate transfer unit 50, and the fixing unit of the above-described embodiment. The present invention may also be applied to a cartridge for charging, transfer, cleaning, fixing, exposure, static elimination, and other replacement members.

  In the above embodiment, a color printer has been described as an example, but the present invention can also be applied to a monochrome printer. Further, the present invention is not limited to a printer, and can be applied to an image forming apparatus such as a copying machine, a facsimile machine, a complex machine of these, or a printing machine. Furthermore, the present invention is not limited to the electrophotographic method, and can be applied to a direct recording method, an electrostatic recording method, and an ink jet method image forming apparatus.

1 is a schematic configuration diagram of a color printer which is an embodiment of an image forming apparatus. FIG. 3 is a perspective view illustrating a state where a cover of the main body is closed and a toner cartridge is mounted. The perspective view seen from the inner side of the front wall of a main body. The perspective view of a rotation rack and a toner cartridge. FIG. 3 is a perspective view of a toner cartridge. The perspective view of the process cartridge of the state which removed the positioning part. FIG. 6 is a front view showing a toner recovery box attached state. The perspective view of a toner collection box. The front view which shows the relationship between a process cartridge and an opening part. The front view which shows the relationship between a process cartridge and an opening part. The schematic plan view which shows the state at the time of mounting | wearing of a process cartridge in order. FIG. 5 is a schematic side view showing a first positioning state of the process cartridge. FIG. 4A is a side view of a rotating rack showing a state before mounting a process cartridge, and FIG. 4B is a schematic side view showing a final positioning state of the process cartridge. FIG. 3 is a schematic front view showing a final positioning state of a process cartridge.

10 Color Printer 200 Toner Cartridge (Process Cartridge)
201 Unit parts 104 and 105 Rib (1st press part)
106 Pressing lever (third pressing part)
110 Cover 111 Projection (second pressing part)
125, 126 First and second positioning recesses (engaged portions)
215, 216 First and second positioning convex portions (positioning portions)
220, 221 First and second step portions (first, second, and third pressed portions)

Claims (6)

An image is formed by using a process cartridge having an element necessary for image formation that can be attached to and detached from a rotating rack that is rotated and provided in the main body of the image forming apparatus, and an element of the process cartridge and other elements necessary for an image forming process. In an image forming apparatus comprising image forming means for forming
The process cartridge is
A unit section having a current image roller as a necessary elements to the image forming process,
The process cartridge moves to the image forming apparatus body in the direction of the rotation axis of the rotating rack in conjunction with the process cartridge moving around the rotation axis of the rotating rack in the image forming apparatus body by the rotation of the rotating rack. An image forming apparatus comprising a first pressed portion that is pressed by a first pressing portion provided in a main body of the image forming apparatus in a mounting direction and positions the process cartridge at a first predetermined position of the main body of the image forming apparatus. A positioning portion that engages with an engaged portion provided in the image forming apparatus main body and positions the unit portion at a predetermined mounting position of the image forming apparatus main body;
The image forming apparatus according to claim 1, wherein the positioning portion includes the first pressed portion. In conjunction with opening and closing of the cover of the image forming apparatus main body, wherein the rotation axis direction is a by the process cartridge carousel in the direction of attaching to the image forming apparatus main body, is pressed by the second pressing portion provided on the cover, the The image forming apparatus according to claim 1, further comprising a second pressed portion that positions the process cartridge at a second predetermined position of the image forming apparatus main body. When the process cartridge moves in the image forming apparatus main body to the third predetermined position, the image forming apparatus main body is provided in the direction of the rotation axis of the rotating rack and in the direction in which the process cartridge is attached to the image forming apparatus main body. The image forming apparatus according to claim 1, further comprising a third pressed portion that is pressed by the three pressing portions and positions the process cartridge at the third predetermined position.   The image forming apparatus according to claim 3, wherein the first pressed portion and the second pressed portion are the same portion.   The first pressed portion and the second pressed portion are not pressed by the first pressed portion and the second pressed portion when the process cartridge is completely attached to the image forming apparatus main body. The image forming apparatus according to claim 3.

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