JP5007698B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile machine, and a composite machine of these, and in particular, includes a photosensitive unit provided with a photosensitive member and a developing roller for conveying the developer to the photosensitive member. In an image forming apparatus in which the developing unit can be separated, the photosensitive unit and the developing unit can be separated to easily perform the work of separately exchanging the photosensitive unit and the developing unit. This is characterized in that the positional relationship between the body and the developing roller can be appropriately set.

  2. Description of the Related Art Conventionally, image forming apparatuses such as copiers, printers, facsimiles, and multifunction machines of these have various configurations.

  As one of such image forming apparatuses, in recent years, a photoconductor unit provided with a photoconductor and a development unit provided with a developing roller for conveying the developer to the photoconductor are provided in a separable manner. A photoconductor unit and a development unit that can be individually replaced are used.

  Here, in the image forming apparatus as described above, when the photoreceptor unit and the development unit are provided to be separable, the photoreceptor unit and the development unit are rotated by pins as shown in Patent Documents 1 to 4 and the like. Proposed to be mounted movably.

  However, when the photosensitive unit and the developing unit are rotatably attached by the pins as described above, it is necessary to remove the above-mentioned pins in order to separate and replace the photosensitive unit and the developing unit. Therefore, the work of separating and replacing the photosensitive unit and the developing unit is cumbersome and time-consuming, and the positional accuracy of the pin is deteriorated or the pin is deformed. There has been a problem that the positional relationship with the developing roller in the unit fluctuates, making it impossible to form a good image.

  Further, as shown in Patent Document 5, pins are provided on both sides in the longitudinal direction of the developing unit, while overhanging side walls provided with support holes for inserting the pins are provided on both sides of the photosensitive unit. There has also been proposed a structure in which the photosensitive unit and the developing unit are provided so as to be separable by elastically deforming the side wall and inserting or removing the pin into or from the support hole.

However, the operation of elastically deforming the overhanging side wall and inserting or removing the pin into or from the support hole is troublesome, and if the above operation is repeated many times, the overhanging side wall is However, it gradually plastically deforms, changing the positional relationship between the photoconductor in the photoconductor unit and the developing roller in the developing unit, resulting in problems such as failure to form a good image and breakage of the protruding side wall. It was.
JP-A-6-110263 JP-A-8-110748 JP 2000-293086 A JP 2001-154565 A Japanese Patent Laid-Open No. 2004-271654

  The present invention relates to an image forming apparatus in which a photoconductor unit including a photoconductor and a developing unit including a developing roller that conveys a developer to the photoconductor are detachable. It is an object of the present invention to make it possible to easily perform the work of separately exchanging the photosensitive unit and the developing unit and to appropriately set the positional relationship between the photosensitive member and the developing roller. Is.

  In the image forming apparatus of the present invention, in order to solve the above-described problems, a photoconductor unit provided with a photoconductor and a development unit provided with a developing roller that conveys developer to the photoconductor can be separated. In the image forming apparatus provided in the image forming apparatus, a rotating member that rotates about a fulcrum is provided on at least one axial end side of the photosensitive member in the photosensitive unit, and the developing member in the developing unit is provided on the rotating member. A holding portion that holds the developing roller rotatably while being in contact with a rotating shaft portion on one end side of the roller and an operation portion that rotates and rotates the rotating member to hold and release the developing roller by the holding portion are provided. An urging means is provided for urging the holding portion of the rotating member in contact with the rotating shaft portion of the developing roller, and is further brought into contact with the rotating shaft portion of the developing roller held by the holding portion. The The positioning member for positioning the image rollers to attach movably.

  Here, in the image forming apparatus of the present invention, the rotating shaft portion of the developing roller may be the rotating shaft itself of the developing roller or a rotating roller rotatably attached to the rotating shaft of the developing roller. However, in particular, if the holding part or positioning member of the rotating member is brought into contact with and held by a rotating roller rotatably attached to the rotating shaft of the developing roller, the contact with the holding part or the positioning member is possible. This prevents the rotation of the developing roller from being suppressed.

  Further, when mounting the positioning member movably, it is preferable that the positioning member is mounted so as to move along a line connecting the center of the photoreceptor and the center of the developing roller held by the holding portion. .

  In the image forming apparatus of the present invention, the rotating member, the urging unit, and the positioning member may be provided at least on one end side in the axial direction of the photosensitive member in the photosensitive unit. In order to more easily separate the developing unit from each other and to set the positional relationship between the photosensitive member and the developing roller more appropriately, the rotating member, the biasing unit, and the positioning member are provided. It is preferable to provide the photoconductor unit on both sides in the axial direction of the photoconductor.

  In the image forming apparatus of the present invention, as described above, a rotating member that rotates about a fulcrum is provided on at least one axial end side of the photosensitive member in the photosensitive unit, and the above-described development is provided in a holding portion of the rotating member. The rotating shaft portion on one end side of the developing roller in the unit is brought into contact so that the developing roller is rotatably held by the holding portion, and the operation portion provided on a different side through the holding portion and the fulcrum is used. The developing member is rotated to hold and release the developing roller by the holding unit.

  For this reason, in the image forming apparatus of the present invention, the photosensitive member unit is attached to the developing unit by rotating the rotating member by the operation unit and holding and releasing the developing roller by the holding unit. The operation of separating the photosensitive unit from the developing unit can be easily performed, and the operation of individually replacing the photosensitive unit and the developing unit can be easily performed.

  In the image forming apparatus of the present invention, the holding portion of the rotating member is brought into contact with the rotating shaft portion on one end side of the developing roller in the developing unit, and the developing roller is rotatably held. Since the holding portion is urged by the urging means, the developing roller is held at an appropriate position by the holding portion of the rotating member, and the photosensitive unit and the developing unit are arbitrarily separated. Will be prevented.

  In the image forming apparatus of the present invention, since the positioning member for positioning the developing roller by being brought into contact with the rotating shaft portion of the developing roller held by the holding unit is movably attached, the positioning member By appropriately moving and mounting the developing roller, the developing roller can be set at an appropriate position with respect to the photoconductor in the photoconductor unit. In particular, the positioning member is held by the center of the photoconductor and the holding portion. If the developing roller is mounted so as to move along a line connecting the center of the developing roller, the developing roller can be appropriately held at a position facing the photosensitive member with a required interval.

  In the image forming apparatus according to the present invention, when the rotating member, the urging unit, and the positioning member are provided on both sides of the photosensitive member in the axial direction of the photosensitive member, the rotating members on both sides are rotated. The work of attaching the photoconductor unit to the development unit or separating the photoconductor unit from the development unit is further simplified, and the work of individually replacing the photoconductor unit and the development unit can be performed more easily. At the same time, the developing roller can be held more appropriately at a position facing the photoconductor with a required interval.

  Next, an image forming apparatus according to an embodiment of the present invention will be specifically described with reference to the accompanying drawings. Note that the image forming apparatus according to the present invention is not limited to those shown in the following embodiments, and can be implemented with appropriate modifications within a range not changing the gist thereof.

  In the image forming apparatus according to this embodiment, as shown in FIG. 1, the photosensitive member 11, the charging device 12 for charging the photosensitive member 11, and the toner remaining on the surface of the photosensitive member 11 after the transfer are removed. The photosensitive unit 10 provided with the cleaning device 13 and the developing unit 20 provided with the developing roller 21 that conveys the developer to the photosensitive member 11 are made separable, and each of the four photosensitive units 10 and 10 is separated. A developing unit 20 is provided in the main body 1 of the image forming apparatus, and each developing unit 20 contains a developer containing toners of different colors of black, yellow, magenta, and cyan. In this embodiment, the photosensitive member 11 and the developing roller 21 are provided so as to face each other with a required interval. However, the photosensitive member 11 and the developing roller 21 may be provided so as to contact each other. It is.

  Here, in the image forming apparatus of this embodiment, when full-color image formation is performed, the photoreceptor 11 in each photoreceptor unit 10 is rotated, and the surface of each photoreceptor 11 is charged by the charging device 12. Then, each of the charged photoreceptors 11 is exposed according to the image data by the exposure device 31 to form an electrostatic latent image on the surface of each photoreceptor 11.

  Then, a developer containing toner of each color is conveyed to each photoconductor 11 on which the electrostatic latent image is formed in this manner by a developing roller 21 provided in each corresponding developing unit 20, and A toner image of each color corresponding to the electrostatic latent image is formed on the surface of the body 11.

  Next, the toner images of the respective colors formed on the respective photoconductors 11 are primarily transferred sequentially to an intermediate transfer body 33 in the form of an endless belt that is driven around a roller 32. A full-color toner image is formed on the intermediate transfer member 33, and a residue such as toner remaining on the surface of each photoconductor 11 after the toner image is transferred is provided in each photoconductor unit 10. Further, the cleaning device 13 is used to remove the surface of each photoconductor 11.

  The full-color toner image formed on the intermediate transfer member 33 as described above is guided to a position facing the roller-like secondary transfer device 34, and the sheet-like recording medium S is transferred to the intermediate transfer member. 33 and the secondary transfer device 34, the full-color toner image formed on the intermediate transfer body 33 by the secondary transfer device 34 is secondarily transferred to the recording medium S, while the full-color toner image Residue such as toner remaining on the surface of the intermediate transfer member 33 after the toner is transferred is removed from the surface of the intermediate transfer member 33 by the cleaning device 36.

  Then, the recording medium S to which the full color toner image is transferred as described above is guided to the fixing device 35 and the transferred full color toner image is fixed to the recording medium S, and then the full color toner image is fixed. The recording medium S is discharged.

  Here, in the image forming apparatus according to this embodiment, when the photosensitive unit 10 and the developing unit 20 are detachably provided, as shown in FIG. 2, the developing roller 21 provided in the developing unit 20 is provided. The rotating roller 21b is rotatably attached to the rotating shaft 21a, while the rotating shaft 21a of the developing roller 21 is rotatable on the inner surface side of the side wall 10a of the axial end portion of the photosensitive member 11 in the photosensitive unit 10. And a pivot member 15 that pivots around a fulcrum 15a.

  In this embodiment, the rotating member 15 is provided with a holding portion 15b that contacts the rotating roller 21b that is rotatably attached to the rotating shaft 21a of the developing roller 21 and holds the developing roller 21 rotatably. At the same time, an operating portion 15c is provided on a different side via the holding portion 15b and the fulcrum 15a to hold and release the developing roller 21 by the holding portion 15b.

  Further, a biasing member 16 made of a pressing spring is attached to the operating portion 15c of the rotating member 15, and the operating portion 15c is biased so as to push the holding portion 15b. The urging is performed while being in contact with the roller 21b.

  In this embodiment, the positioning member 17 is provided so as to face the holding portion 15b via the rotating roller 21b, and the positioning member 17 is held by the center of the photoreceptor 11 and the holding portion 15b. It attaches so that it can move along the line which connects with the center of the developing roller 21, and makes the holding | maintenance part 15b in the rotation member 15 contact | abut to the rotation roller 21b of the developing roller 21 as mentioned above, and is different from this holding | maintenance part 15b. At the position, the rotating roller 21b is brought into contact with the positioning member 17. In this embodiment, the rotating roller 21b is brought into contact with the holding portion 15b at one location and the positioning member 17 at two locations, and these three abutting positions correspond to the rotating roller 21b. The circumference is divided into three equal parts.

  Here, in this embodiment, when mounting the positioning member 17 so as to be movable along a line connecting the center of the photoconductor 11 and the center of the developing roller 21 held by the holding portion 15b, The positioning member 17 is provided with a long hole 17a along the above-described line, and the positioning member 17 is attached to the side wall 10a of the photosensitive unit 10 by the screw 17b through the long hole 17a. A position adjusting hole 17c for adjusting the position of the positioning member 17 is provided by inserting a position adjusting cam (not shown) into the position adjusting hole 17c.

  Then, the position adjusting cam is inserted into the position adjusting hole 17c, the position adjusting cam is rotated, the positioning member 17 is slid along the elongated hole 17a, and the photosensitive member 11 and the developing roller 21 are moved. After adjusting the facing distance, the screw 17b is tightened to fix the positioning member 17 to the side wall 10a of the photosensitive unit 10.

  In this way, the rotating roller 21b of the developing roller 21 is sandwiched between the holding portion 15b and the positioning member 17, the developing roller 21 is positioned at a predetermined position, and the photosensitive member 11 and the developing roller 21 are predetermined. It comes to oppose through an interval. Note that the method of attaching the positioning member 17 so as to move along the line connecting the center of the photosensitive member 11 and the center of the developing roller 21 held by the holding portion 15b is not particularly limited to the above. .

  In the image forming apparatus according to this embodiment, when the photosensitive unit 10 and the developing unit 20 are separated and either or both of the photosensitive unit 10 and the developing unit 20 are replaced, The image forming apparatus main body 1 is taken out and the operating member 15c of the rotating member 15 is pushed against the biasing member 16 made of the pressing spring to rotate the rotating member 15, and the developing roller 21 is rotated as described above. The holding portion 15b of the rotating member 15 in contact with the rotating roller 21b is rotated in a direction away from the rotating roller 21b of the developing roller 21, so that the holding of the developing roller 21 by the holding portion 15b is released. To.

  Then, in the state where the holding of the developing roller 21 by the holding portion 15b is released as described above, the above-described photosensitive unit 10 is lifted, and the photosensitive unit 10 is separated from the developing unit 20 as shown in FIG. Either one or both of the photosensitive unit 10 and the developing unit 20 are exchanged.

  Further, when one or both of the photosensitive unit 10 and the developing unit 20 are exchanged and used in the image forming apparatus as described above, the rotating roller 21b of the developing roller 21 is used as the rotating member 15 as described above. The developing roller 21 is positioned so that the rotating roller 21b of the developing roller 21 is sandwiched between the holding portion 15b and the positioning member 17 so that the developing roller 21 is positioned. And the developing roller 21 are opposed to each other with a predetermined interval, and the photosensitive unit 10 is attached to the developing unit 20.

  Here, when the interval between the photoconductor 11 and the developing roller 21 in the newly installed photoconductor unit 10 and the development unit 20 varies, the positioning member 17 is set to the center of the photoconductor 11 as described above. The positioning member 17 is moved so as to move along a line connecting the center of the developing roller 21 held by the holding portion 15b and the photosensitive member 11 and the developing roller 21 face each other with a predetermined interval. After the adjustment, the positioning member 17 is fixed to the side wall 10a of the photoreceptor unit 10.

  In the image forming apparatus according to this embodiment, the positioning member 17 is slid along the elongated hole 17a when adjusting the distance between the photosensitive member 11 and the developing roller 21 facing each other. It is also possible to adjust the distance between the photosensitive member 11 and the developing roller 21 by tilting the member 17.

1 is a schematic explanatory view showing an image forming apparatus according to an embodiment of the present invention. In the image forming apparatus of the above embodiment, it is a schematic explanatory view showing a state in which a photosensitive unit and a developing unit are provided in a separable manner. FIG. 3 is a partial perspective view showing a state where a photosensitive unit and a developing unit are separated in the image forming apparatus of the embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus main body 10 Photoconductor unit 10a Side wall 11 Photoconductor 12 Charging device 13 Cleaning device 14 Bearing part 15 Rotating member 15a Support point 15b Holding part 15c Operation part 16 Energizing member 17 Positioning member 17a Elongate hole 17b Screw 17c Position adjustment Hole 20 Developing unit 21 Developing roller 21a Rotating shaft 21b Rotating roller 31 Exposure device 32 Roller 33 Intermediate transfer member 34 Secondary transfer device 35 Fixing device 36 Cleaning device S Recording medium

Claims (5)

  In an image forming apparatus in which a photoconductor unit including a photoconductor and a developing unit including a developing roller that conveys a developer to the photoconductor are detachably provided, at least the photoconductor in the photoconductor unit is provided. A rotating member that rotates about a fulcrum is provided on one axial end side, and the developing roller can be rotated by contacting the rotating member on one end side of the developing roller in the developing unit. A holding portion that holds the developing roller and an operation portion that holds and releases the developing roller by the holding portion by rotating the rotating member, and the holding portion of the rotating member contacts the rotating shaft portion of the developing roller. There is provided a biasing means for biasing the contacted state, and a positioning member for positioning the developing roller by being brought into contact with the rotating shaft portion of the developing roller held by the holding unit is movably movable. An image forming apparatus characterized in that attached.   2. The image forming apparatus according to claim 1, wherein the rotating member, the urging unit, and the positioning member are provided on both sides of the photosensitive member in the axial direction of the photosensitive member.   The image forming apparatus according to claim 1, wherein the positioning member is movably attached along a line connecting the center of the photosensitive member and the center of the developing roller held by the holding unit. An image forming apparatus.   4. The image forming apparatus according to claim 1, wherein the rotating shaft portion of the developing roller is a rotating roller rotatably attached to the rotating shaft of the developing roller. An image forming apparatus, wherein the holding portion and the positioning member in the rotating member are in contact with each other.   5. The image forming apparatus according to claim 1, wherein the developing roller is held by the holding unit at a position facing the photoconductor with a predetermined interval. An image forming apparatus.

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