JP2009276535A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and suitably set the developing roller of a developing unit in a predetermined position with respect to the photoreceptor of a photoreceptor unit, when independently replacing the photoreceptor unit and developing unit in an image forming apparatus in which the photoreceptor unit and developing unit are disposed so as to be brought into contact with or separated from each other. <P>SOLUTION: The image forming apparatus is configured so that the photoreceptor unit 10 having the photoreceptor 11 and the developing unit 20 having the developing roller 21 for conveying developer to the photoreceptor are disposed so as to be brought into contact with or separated from each other. In the image forming apparatus, an adjustment member 14 is movably attached to the axial end of the photoreceptor of the photoreceptor unit, the adjustment member being abutted with the rotation shaft part 22b of an end of the developing roller, thereby adjusting the position of the developing roller with respect to the photoreceptor. <P>COPYRIGHT: (C)2010,JPO&INPIT

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 photoconductor unit including a photoconductor and a developing roller that conveys a developer to the photoconductor. In an image forming apparatus provided with a developing unit so as to be able to approach and be separated from each other, when the photosensitive unit and the developing unit are separated and the photosensitive unit and the developing unit are individually replaced, the photosensitive unit It is characterized in that the developing roller in the developing unit can be easily and appropriately set at a predetermined position with respect to the photoconductor in FIG.

  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 photosensitive unit provided with a photosensitive member and a developing unit provided with a developing roller for transporting the developer to the photosensitive member can be brought close to and separated from each other. The photosensitive member unit and the developing unit are separated from each other so that the photosensitive member unit and the developing unit can be individually replaced.

  Here, when the photosensitive unit and the developing unit are separated from each other as described above and the photosensitive unit and the developing unit are individually replaced, an appropriate image can be formed even after the replacement. In order to achieve this, for example, the developing roller provided in the developing unit is opposed to the photosensitive member provided in the photosensitive unit with a predetermined interval. Therefore, it is necessary to set it appropriately at a predetermined position.

  Here, in the image forming apparatus as described above, in order to set the developing roller provided in the developing unit so as to face the photosensitive member provided in the photosensitive unit with a required interval, in general, in general, A gap roller having an outer diameter larger than the outer diameter of the developing roller is provided on the rotating shaft of the developing roller, and the developing unit is biased toward the photosensitive unit, and the gap roller is placed on the outer peripheral surface of the photosensitive member. The developing roller is made to face the photosensitive member with a predetermined gap by the gap roller.

  However, when the gap roller, which is larger than the outer diameter of the developing roller as described above, is brought into contact with the outer peripheral surface of the photosensitive member to adjust the distance between the developing roller and the photosensitive member, the gap roller has a very high dimension. It is difficult to make the developing roller face the photoconductor at a constant and appropriate distance due to variations in dimensional accuracy, etc., and the photoconductor unit and the development unit can be replaced separately. In such a case, there is a problem that proper image formation cannot be performed.

  Conventionally, as disclosed in Patent Document 1, a bearing for holding the rotating shaft of the developing roller is provided to be movable with respect to the photosensitive member, and in addition to the bearing for holding the rotating shaft of the photosensitive member, the photosensitive member. Providing a gap setting unit that auxiliaryly holds the shaft of the developing roller, and a gap adjusting mechanism for setting the gap between the bearing of the developing roller and the gap setting unit so as to always maintain a constant minute distance is proposed. ing.

  However, in this case, the mechanism for adjusting the developing roller and the photosensitive member to a predetermined distance becomes complicated, and the dimensional accuracy is extremely high with respect to the bearing of the developing roller and the gap setting portion. In addition, if the bearing for holding the rotation shaft of the developing roller is moved as described above, the position of the developing roller in the developing unit is shifted and the developing roller is provided in the developing unit. There has been a problem that the position of the developing roller with respect to a regulating member that regulates the amount of developer conveyed to the photosensitive member by the developing roller, for example, is shifted, and stable image formation cannot be performed.

  Further, as shown in Patent Document 2, a bearing for holding the rotating shaft of the photosensitive member is movably provided, and a position adjusting member for adjusting the position of the bearing is provided. It has been proposed to adjust the position to change the position of the photosensitive member so that the photosensitive member is set at a position facing the developing roller with a predetermined interval.

However, it is very troublesome to change the position of the photosensitive member by adjusting the position of the bearing of the photosensitive member by the position adjusting member so that the photosensitive member faces the developing roller with a predetermined interval. At the same time, there is a problem that it is difficult to set the photosensitive member at a predetermined position. Further, when the position of the photoconductor in the photoconductor unit is changed as described above, it remains on another device provided in the photoconductor unit, for example, a charging device for charging the surface of the photoconductor or the surface of the photoconductor. The position of the photoconductor is shifted with respect to a cleaning device or the like that removes toner, and a latent image forming device that performs exposure according to image information on the photoconductor, or a toner image formed on the surface of the photoconductor is transferred to a transfer medium. There has been a problem that the position of the photoconductor with respect to the transfer device or the like is shifted and stable image formation cannot be performed.
JP 2002-72680 A JP 2005-292426 A

  The present invention provides an image forming apparatus in which a photoconductor unit including a photoconductor and a developing unit including a developing roller that transports a developer to the photoconductor are provided so as to be close to and away from each other. When the unit and the developing unit are separated from each other and the photosensitive unit and the developing unit are individually replaced, the developing roller is exposed to the photosensitive member, for example, by making the developing roller face the photosensitive member with a required interval. It is an object to enable easy and appropriate setting at a predetermined position with respect to the body.

  In the present invention, in order to solve the above-described problems, a photoconductor unit provided with a photoconductor and a developing unit provided with a developing roller that conveys the developer to the photoconductor are provided so as to be close to and away from each other. In the obtained image forming apparatus, the adjusting member for adjusting the position of the developing roller with respect to the photosensitive member is moved to the axial end portion of the photosensitive member in the photosensitive unit so as to be in contact with the rotating shaft portion of the developing roller end portion. I tried to attach it as possible.

  Here, in the image forming apparatus of the present invention, in adjusting the position of the developing roller with respect to the photosensitive member by the adjusting member, in addition to adjusting the photosensitive member and the developing roller to face each other with a predetermined interval, It is also possible to adjust so that the photosensitive member and the developing roller are in proper contact and face each other.

  Further, when the adjustment member is movably attached to the axial end portion of the photoconductor in the photoconductor unit as described above, the adjustment member is attached along the line connecting the center of the photoconductor and the center of the developing roller. It is preferable that the mounting is possible.

  Further, in order to appropriately adjust the position of the developing roller with respect to the photosensitive member in the entire axial direction, it is preferable to provide the adjusting members at both ends of the photosensitive member in the axial direction of the photosensitive member.

  In the image forming apparatus of the present invention, the rotation shaft portion of the developing roller with which the adjusting member is brought into contact may be the rotation shaft of the developing roller itself or rotatably attached to the rotating shaft of the developing roller. Although it may be a rotating roller, in particular, when the adjusting member is brought into contact with the rotating roller rotatably attached to the rotating shaft of the developing roller, the rotation of the developing roller is suppressed by the contact with the adjusting member. It will not be done.

  In the present invention, in an image forming apparatus in which a photosensitive unit provided with a photosensitive member and a developing unit provided with a developing roller for transporting a developer to the photosensitive member are provided so as to be close to and away from each other. An adjustment member is movably attached to the axial end portion of the photoconductor in the photoconductor unit, and this adjustment member is brought into contact with the rotation shaft portion at the end portion of the developing roller to adjust the position of the developing roller with respect to the photoconductor. I did it.

  For this reason, in the image forming apparatus of the present invention, the developing roller is adjusted by a simple operation of adjusting the position of the developing roller with respect to the photosensitive member by bringing the adjusting member into contact with the rotating shaft at the end of the developing roller. The developing roller can be easily and properly set at a predetermined position with respect to the photosensitive member, such as by allowing the photosensitive member to face the photosensitive member with a required interval, and the photosensitive member unit and the developing unit can be replaced separately. Even in this case, the developing roller can be appropriately set at a predetermined position with respect to the photosensitive member, and appropriate image formation can be performed.

  In the image forming apparatus of the present invention, when the adjusting member is attached so as to move along a line connecting the center of the photosensitive member and the center of the developing roller, the developing roller is placed on the photosensitive member with a predetermined interval. Thus, it can be more appropriately held at the opposite positions.

  In the image forming apparatus of the present invention, when the adjusting member is provided at both axial ends of the photosensitive member in the photosensitive unit, the developing roller is set at an appropriate position with respect to the photosensitive member in the entire axial direction. It becomes like this.

  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 brought into a state in which they can be brought close to and separated from each other. 10 and the developing unit 20 are provided in the image forming apparatus main body 1, and each developing unit 20 accommodates 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 in contact with each other. Is possible.

  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. The latent image forming device 31 performs exposure according to the image data on each of the photosensitive members 11 thus charged to form an electrostatic latent image on the surface of each of the photosensitive members 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, as shown in FIGS. 2 and 3, the rotation shaft 11 a of the photoconductor 11 is provided on the side walls 10 a on both sides in the axial direction of the photoconductor 11 in the photoconductor unit 10. A bearing portion 10b that is rotatably held is provided, and an inner surface of the side wall 10a is in contact with a rotating roller 21b that is rotatably attached to a rotating shaft 21a of the developing roller 21 so that the developing roller 21 with respect to the photoreceptor 11 is in contact with the rotating roller 21b. The adjustment member 14 for adjusting the position is movably attached.

  In the image forming apparatus according to this embodiment, when the adjustment member 14 is movably attached as described above, the adjustment member 14 is larger than the hole of the bearing portion 10b that holds the rotating shaft 11a of the photoreceptor 11. A through hole 14a is provided, and the rotating shaft 11a of the photoconductor 11 is rotatably held by the bearing portion 10b through the through hole 14a.

  The adjustment member 14 has two elongated holes 14b along the line L so that the adjustment member 14 moves along a line L connecting the center of the photosensitive member 11 and the center of the developing roller 21. In addition, a position adjusting hole 14d for adjusting the position of the adjusting member 14 is provided by inserting and rotating a position adjusting eccentric pin (not shown), and the adjusting member 14 is adjusted by the screw 14c through each of the long holes 14b. Is attached to the side wall 10a of the photoconductor unit 10.

  In the image forming apparatus according to this embodiment, when setting the developing roller 21 provided in the developing unit 20 so as to face the photosensitive member 11 provided in the photosensitive unit 10 with a predetermined interval therebetween. The adjusting member 14 is temporarily fixed to an appropriate position on the side wall 10a of the photosensitive unit 10 by a screw 14c through each of the long holes 14b provided in the adjusting member 14, and the position adjusting eccentric pin is fixed. The rotating roller 21b attached to the rotating shaft 21a of the developing roller 21 is brought into contact with the adjusting member 14 in this state by being inserted into the hole 10c provided in the side wall 10a of the photosensitive unit 10 through the position adjusting hole 14d. Make contact.

  Next, while measuring the distance between the photoconductor 11 and the developing roller 21, the position adjusting eccentric pin is rotated to connect the adjusting member 14 to the line L connecting the center of the photoconductor 11 and the center of the developing roller 21. In this state, the adjusting member 14 is fixed to a predetermined position on the side wall 10a of the photosensitive unit 10 by the screws 14c. I will let you.

  Thus, the rotating roller 21b of the developing roller 21 is brought into contact with the adjusting member 14 so that the developing roller 21 is positioned at a predetermined position, and the photoconductor 11 and the developing roller 21 face each other with a predetermined interval. Thus, even when the photoconductor unit 10 and the developing unit 20 are individually replaced, the developing roller 21 can be set at an appropriate position with a predetermined distance from the photoconductor 11, and appropriate image formation can be performed. Can be performed stably. A method for attaching the position adjusting member 14 so as to be movable along a line L connecting the center of the photosensitive member 11 and the center of the developing roller 21 is not particularly limited to the above.

  In the image forming apparatus according to this embodiment, an example of a full-color image forming apparatus provided with a plurality of photosensitive units 10 and developing units 20 has been described. However, one photosensitive unit 10 and one developing unit 20 are provided. It may be a monochrome image forming apparatus provided.

1 is a schematic explanatory view showing an image forming apparatus according to an embodiment of the present invention. In the image forming apparatus according to the above-described embodiment, the position of the developing roller with respect to the photosensitive member is adjusted by contacting the rotating roller attached to the rotating shaft of the developing roller on the side wall of the axial end portion of the photosensitive member in the photosensitive unit. It is the schematic explanatory drawing which showed the state which attached the adjustment member to perform so that a movement was possible. In the image forming apparatus according to the above-described embodiment, the adjusting member attached to the side wall of the photosensitive unit is brought into contact with the rotating roller attached to the rotating shaft of the developing roller so that the developing roller is appropriately connected to the photosensitive member through a predetermined interval. It is the partial explanatory view which showed the state set to the correct position.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus main body 10 Photoconductor unit 10a Side wall 10b Bearing part 10c Hole 11 Photoconductor 12 Charging device 13 Cleaning device 14 Adjustment member 14a Through hole 14b Long hole 14c Screw 14d Position adjustment hole 20 Developing unit 21 Developing roller 21a Rotating shaft 21b Rotating roller 31 Latent image forming device 32 Roller 33 Intermediate transfer member 34 Secondary transfer device 35 Fixing device 36 Cleaning device L Line connecting the center of the photosensitive member and the center of the developing roller S Recording medium

Claims (5)

  In the 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 provided so as to be close to and away from each other, the photoconductor in the photoconductor unit An image forming apparatus characterized in that an adjustment member that adjusts the position of the developing roller relative to the photosensitive member by being brought into contact with the rotating shaft at the end of the developing roller is movably attached to the end in the axial direction.   2. The image forming apparatus according to claim 1, wherein an interval between the photosensitive member and the developing roller is adjusted by the adjusting member.   3. The image forming apparatus according to claim 1, wherein the adjustment member is attached so as to be movable along a line connecting the center of the photosensitive member and the center of the developing roller. Forming equipment.   4. The image forming apparatus according to claim 1, wherein the adjusting member is provided at both ends of the photosensitive unit in the axial direction of the photosensitive member. 5. apparatus.   5. 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 adjustment member is in contact with the image forming apparatus.

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