JP2014157373A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus which can be simply and surely operated by a general user, without fail, in the replacement work of an image carrier unit.SOLUTION: A copying machine includes an operation member 20 which is freely displaceable between a first position where two or more members (a developing unit c2, a transfer roller, etc.) are interlocked with each other, to be located at a proximity position and a second position where two or more members are interlocked with each other, to be located at a separate position. The operation member 20 includes a rotary shaft 22 to which a lever member 21 is connected and cam members 23 provided in the rotary shaft 22 and moving the developing unit c2 between the proximity position and the separate position, according to the displacement around the axis of the rotary shaft 22. The cam members 23 are provided as a pair at an interval in the axial direction of the rotary shaft 22 and the developing unit c2 is moved in a contact state with the cam members 23 at two points.

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, or a facsimile machine.

  In the image forming apparatus described in Patent Document 1, an electrostatic latent image is formed on an image carrier such as a photosensitive drum, the electrostatic latent image is developed with toner, and the developed toner image is transferred to a predetermined sheet. It is configured to transfer to the material. For this purpose, two or more members, for example, a developing roller for developing a toner image, a transfer roller for transferring a toner image to a sheet material, and the like are arranged on the peripheral surface of the image carrier to face each other.

  Incidentally, the image carrier is generally unitized so as to be detachable from the apparatus main body in a predetermined direction (for example, the axial direction of the drum). When replacing the image carrier unit, in order to remove the image carrier unit from the apparatus main body, the two or more members that are in contact with or close to the peripheral surface of the image carrier are removed from the image carrier. Need to be separated.

In the image forming apparatus described in Patent Document 2 below, when a unit (image carrier unit including an intermediate transfer belt) is attached to or detached from the apparatus main body, a member abutting against the unit is interlocked with the unlocking of the unit. It is configured to perform contact release.
Specifically, the secondary transfer roller provided on the open / close cover is interlocked with the unlocking of the unit by interlocking the latch release of the open / close cover provided on the side of the apparatus body with the unlocking of the unit. Thus, it is configured to be separated from the opening / closing cover.

JP 2001-134164 A JP 2007-304500 A

  However, in the above prior art, an operation of closing the opening / closing cover is required after replacement of the image carrier unit. This operation is not a problem when a so-called service person who is familiar with the internal configuration of the apparatus performs the operation. For example, when the image carrier unit is set as a user replaceable unit, a general user performs this operation. Therefore, an unexpected problem may occur.

  For example, when the image carrier unit is pulled out to the front side of the apparatus main body, it is necessary to operate the opening / closing cover on the side of the apparatus main body, which is an operation that is difficult to imagine intuitively. For this reason, after the image carrier unit is replaced, there is a risk of forgetting to close the open / close cover on the side of the apparatus body.

  Further, for example, when the opening / closing cover is opened in conjunction with the unlocking of the unit, the user does not know the reason, and there is a fear that the user may feel anxious about why it is opened. Also, if the user forgets about the open / close cover, or if the amount of the open / close cover is small and he / she has not noticed, forget to close the open / close cover.

  In addition, when the image carrier unit is removed, the open / close cover automatically opens. However, when installing the image carrier unit, the open / close cover must be manually closed. The operation becomes different and the possibility of an erroneous operation increases, and the operation becomes complicated.

  The present invention has been made in view of the above problems, and provides an image forming apparatus that is simple and can be surely operated by a general user with respect to an image carrier unit replacement operation. With the goal.

  In order to solve the above-described problems, the present invention provides an image forming apparatus in which an image carrier unit having an image carrier that carries a toner image is detachably provided in a predetermined direction with respect to the apparatus main body. Each of the two or more members including two or more members arranged to face the image carrier in a direction other than the predetermined direction when the image carrier unit is attached to the apparatus main body. Are independently provided so as to be movable between a proximity position in contact with or close to the image carrier and a separation position separated from the image carrier. An operating member that is displaceable between a first position that links each of the two or more members to the close position and a second position that links each of the two or more members to the spaced position. The two or more members have a front A developing unit having a developing roller for developing a toner image; and a transfer roller for transferring the toner image of the image carrier onto a predetermined sheet material. The operating member is a rotating shaft to which a lever member is connected. And a cam member that is provided on the rotation shaft and moves the developing unit between the proximity position and the separation position in accordance with a displacement around the rotation shaft, and is connected to the rotation shaft and rotates. A link member that moves the transfer roller between the proximity position and the separation position in accordance with a displacement around the axis of the shaft, and the cam member is spaced apart in the axial direction of the rotation shaft A pair is provided, and the developing unit employs a configuration in which the developing unit moves in contact with the cam member at two points.

  In the present invention, the link member is provided in pairs in the axial direction of the rotation shaft, and the transfer roller moves in contact with the link member at two points at both ends. Adopting a configuration to do.

  In the present invention, the two or more members further include a transfer guide plate that guides the sheet material between the image carrier and the transfer roller, and the link member is displaced around the rotation axis. And a contact portion that moves the transfer roller between the proximity position and the separation position, and the transfer guide plate between the proximity position and the separation position according to a displacement around the rotation axis. A configuration of having a hook part to be moved is adopted.

  In the present invention, the contact portion and the hook portion are arranged with a clearance from the transfer roller and the transfer guide plate when the transfer roller and the transfer guide plate are located at the close position. The configuration is adopted.

  According to the present invention, the operation for replacing the image carrier unit can be performed simply and surely by a general user without fail.

1 is a schematic configuration diagram of a copying machine according to an embodiment of the present invention. It is a perspective view which shows the external appearance of the apparatus main body in embodiment of this invention. It is an expansion perspective view which shows the principal part in FIG. It is a block diagram which shows arrangement | positioning of each unit when the operation member in embodiment of this invention is located in a 1st position. It is a block diagram which shows arrangement | positioning of each unit when the operation member in embodiment of this invention is located in a 2nd position. It is a perspective view which shows the bottom face side external appearance of the operation member in embodiment of this invention. It is an expansion perspective view which shows the principal part in FIG. It is a perspective view which shows the plane side external appearance of the operation member in embodiment of this invention. It is a perspective view which shows the principal part in FIG.

  Hereinafter, an embodiment of an image forming apparatus according to the present invention will be described with reference to the drawings. In the following drawings, the scale of each member is appropriately changed in order to make each member a recognizable size. In the following description, an XYZ orthogonal coordinate system may be set, and the positional relationship of each member may be described with reference to this XYZ orthogonal coordinate system.

(Schematic configuration of image forming apparatus)
FIG. 1 is a schematic configuration diagram of a copying machine P according to an embodiment of the present invention.
The copying machine (image forming apparatus) P includes a discharge unit a, a toner storage unit b, an image forming unit c, and a paper unit d. Further, the copying machine P is provided with a transport section e from a sheet section d positioned at the lower part to a discharge section a positioned at the upper section. In addition, the copying machine P is provided with a scanner unit f for reading a document on the upper portion of the discharge unit a.

The discharge unit a is configured such that a sheet (sheet material) on which a predetermined image is formed is discharged through the transport unit e. The bottom surface of the discharge part a is inclined so that when a plurality of sheets are discharged, one end side is aligned and stacked.
The toner storage unit b is made of, for example, a black toner (BK) toner container, and is configured to supply toner to the developing unit c2 of the image forming unit c.

The image forming unit c includes a laser scanning unit c1, a developing unit c2, a drum unit c3, a transfer unit c4, and a fixing unit c5.
Similarly to the known laser scanning unit, the laser scanning unit c1 includes a light beam generator that generates laser light, a polygon mirror that scans a light beam emitted from the light beam generator, and the polygon mirror. And an fθ lens (both not shown) that forms an image on a photosensitive drum (image carrier) 1 described later.

The developing unit c <b> 2 develops an electrostatic latent image formed on the peripheral surface of the photosensitive drum 1 by supplying toner to the photosensitive drum 1. The developing roller 2 is disposed so as to face each other in the radial direction.
The drum unit c3 is a photosensitive drum on which an electrostatic latent image is generated on the circumferential surface of the drum by using the laser scanning unit c1 and a toner image is formed by toner supplied from the toner storage unit b to the developing unit c2. 1

Around the photosensitive drum 1, a charger 3 for charging the peripheral surface thereof and a cleaner 4 for removing toner remaining on the peripheral surface after the transfer are opposed to each other. The charger 3 and the cleaner 4 of the present embodiment are detachably united together with the photosensitive drum 1 as a drum unit c3.
The transfer unit c4 includes a transfer roller 5 that is disposed to face the circumferential surface of the photosensitive drum 1 in the radial direction. The transfer roller 5 is provided so as to press the photosensitive drum 1.

  Accordingly, when the photosensitive drum 1 is driven to rotate, the transfer roller 5 can rotate along with the rotation. In addition, when a predetermined sheet material, for example, a sheet has been conveyed through the conveying unit e, the transfer roller 5 can be rotated while the sheet is interposed between the photosensitive drum 1 and the sheet. The sheet can be conveyed to the fixing unit c5 side.

  The fixing unit c5 is provided in a part of the transport unit e on the downstream side of the transfer unit c4, and is a pair of rollers arranged so as to sandwich the paper transported through the transport unit e. It is configured. The fixing unit c5 is configured so that the toner image on the paper transferred by the transfer unit c4 by being pressed and heated by the pair of rollers can be fixed on the paper.

  The paper portion d includes a paper feed tray d1 provided so as to be openable and closable with respect to the apparatus main body 10 and a paper feed cassette d2 provided so as to be drawable with respect to the apparatus main body 10. The sheet feeding tray d1 or the sheet feeding cassette d2 is configured to be able to supply sheets one by one to the transport unit e.

  The conveyance part e is provided from the paper part d located in the lower part to the discharge part a located in the upper part, and includes a plurality of conveyance rollers and a guide plate. The transport unit e is configured to transport the sheets supplied from the sheet unit d one by one toward the discharge unit a.

  In the copying machine P configured as described above, an electrostatic latent image is formed by irradiating the photosensitive drum 1 with laser light corresponding to the image data from the laser scanning unit c1, and the toner image is developed with the supplied toner. . The toner image carried on the photosensitive drum 1 is transferred to a sheet by the transfer unit c4, and then subjected to a fixing process by being pressurized and heated by the fixing unit c5. Finally, the sheet on which the image is printed is discharged to the discharge unit a.

(Configuration of the device body and each unit)
FIG. 2 is a perspective view showing an appearance of the apparatus main body 10 according to the embodiment of the present invention. FIG. 3 is an enlarged perspective view showing a main part in FIG.
As shown in FIG. 2, a cover 11 on the front side (+ Y side) of the apparatus main body 10 is provided so as to be freely opened and closed. When the cover 11 is opened, as shown in FIG. 3, a part of the drum unit c3 and a part of the toner storage part b are exposed outside the apparatus.

  The drum unit c3 is provided with a handle 12, and is configured to be detachable in a predetermined direction (Y-axis direction) with respect to the apparatus main body 10 by a guide (not shown). Therefore, the photosensitive drum 1 and a part of its peripheral members can be integrally removed from the apparatus main body 10 by pulling out the drum unit c3 to the front side.

In the drum unit c3, by operating an operation member 20 provided below the handle portion 12, two or more members disposed facing the photosensitive drum 1 inside the apparatus main body 10 are separated from each other, and a predetermined direction is obtained. It is configured to be detachable.
Hereinafter, the configuration of the operation member 20 will be described with reference to FIGS. 4 to 9.

  FIG. 4 is a configuration diagram showing the arrangement of the units when the operation member 20 is located at the first position in the embodiment of the present invention. FIG. 5 is a configuration diagram showing the arrangement of the units when the operation member 20 is located at the second position in the embodiment of the present invention. FIG. 6 is a perspective view showing the bottom side appearance of the operation member 20 according to the embodiment of the present invention. FIG. 7 is an enlarged perspective view showing a main part in FIG. FIG. 8 is a perspective view showing an external appearance of the operation member 20 on the plane side according to the embodiment of the present invention. FIG. 9 is a perspective view showing a main part in FIG.

  As shown in FIG. 4, when the drum unit c <b> 3 is mounted on the apparatus main body 10, two or more members are arranged facing the photosensitive drum 1 in a direction other than a predetermined direction (Y-axis direction). The two or more members of the present embodiment include a developing unit c2 having a developing roller 2 that develops a toner image, and a transfer roller 5 that transfers the toner image on the photosensitive drum 1 to a predetermined sheet material.

  The developing unit c2 moves between a proximity position that is in contact with or close to the photosensitive drum 1 as shown in FIG. 4 and a separation position that is separated from the photosensitive drum 1 as shown in FIG. It is provided freely. The developing unit c2 is urged and pressed by the pressing unit 13 from the separation position toward the proximity position. The pressing unit 13 is provided so as to be slidable in the X-axis direction and is biased to the + X side by a pressing spring (biasing member) 14 fixed to the apparatus main body 10.

  The developing unit c2 has a long hole 16 into which a rotation fulcrum 15 provided in the apparatus main body 10 is fitted. The long hole 16 extends in the X-axis direction. When the developing unit c <b> 2 is pressed to the + X side by the pressing unit 13, the developing unit c <b> 2 moves in the X-axis direction through the long hole 16, and rotates when the rotation fulcrum 15 contacts the side wall on the −X side of the long hole 16. Move in the direction. That is, the developing unit c2 is rotated in the counterclockwise direction in FIG. 4 around the rotation fulcrum 15 so that the developing roller 2 is positioned in a proximity position where the developing roller 2 is pressed and positioned on the photosensitive drum 1.

  As shown in FIG. 4, the transfer roller 5 moves between a proximity position that is in contact with or close to the photosensitive drum 1 and a separation position that is separated from the photosensitive drum 1 as shown in FIG. It is provided freely. The transfer roller 5 is urged and pressed by the pressing spring 17 from the separated position toward the close position. The transfer unit c4 having the transfer roller 5 is configured to be rotatable about the rotation fulcrum 19 shown in FIGS. 4 and 5 when the side cover 18 of the apparatus main body 10 shown in FIG. 2 is opened.

  The operating member 20 is a first position where the developing unit c2 and the transfer roller 5 that can be moved close to / separated from the photosensitive drum 1 independently as described above are positioned close to each other (see FIG. 4). And a second position (see FIG. 5) where each of the developing unit c2 and the transfer roller 5 is interlocked and positioned at a separated position. Further, when the operation member 20 is displaced from the first position to the second position, the developing unit c2 and the transfer roller 5 are moved from the proximity position to the separation position against the urging force of the pressing unit 13 and the pressing spring 17. It is configured to move.

  Specifically, the operation member 20 is provided on the rotation shaft 22 to which the lever member 21 is connected, and the rotation shaft 22, and the developing unit c <b> 2 is moved between the proximity position and the separation position according to the displacement around the rotation shaft 22. And a link member 24 that is connected to the rotation shaft 22 and moves the transfer roller 5 between the proximity position and the separation position in accordance with the displacement around the rotation shaft 22. .

  The rotary shaft 22 is provided so as to be rotatable around an axis extending in the Y-axis direction by a bearing portion (not shown) provided in the apparatus main body 10. A lever member 21 is connected to the + Y side end of the rotating shaft 22 (see FIG. 6). As shown in FIG. 3, the lever member 21 is configured to be exposed to the front side (+ Y side) of the apparatus main body 10 together with the drum unit c3 when the cover 11 is opened. As shown in FIG. 3, the position at which the lever member 21 assumes a substantially oblique 45 degree position is the first position (see FIG. 4). In addition, the posture in which the lever member 21 is tilted substantially horizontally from the posture is the second position (see FIG. 5).

  The cam member 23 has a substantially claw shape with a rounded tip, and is fixed to the rotating shaft 22 at a predetermined angle. The distal end portion of the cam member 23 is configured to be able to contact the pressing unit 13. The pressing unit 13 has a contact surface 13 a having a predetermined curvature centered on a position below the rotation shaft 22 and not centered with the rotation shaft 22. Therefore, when the cam member 23 is moved by the rotation of the rotary shaft 22, the contact position between the tip end portion of the cam member 23 and the contact surface 13a of the pressing unit 13 is displaced in the X-axis direction (FIG. 4 and FIG. 4). (See FIG. 5).

  As shown in FIG. 6, the cam members 23 are provided in pairs on the rotary shaft 22 with a gap in the Y-axis direction. The cam members 23 are provided at positions corresponding to both sides of the pressing unit 13 in the width direction. The pressing unit 13 also has contact surfaces 13a corresponding to the cam members 23, respectively. Therefore, the pressing unit 13 can stably move in the X-axis direction by contacting the cam member 23 at two points.

As shown in FIG. 4, the link member 24 includes a rotating frame 25 that is rotatably provided with respect to the apparatus main body 10, and a connecting frame 26 that connects the rotating shaft 22 and the rotating frame 25.
As shown in FIG. 7, the rotary frame 25 is provided to be rotatable around an axis extending in the Y-axis direction by a rotation fulcrum pin 27 fixed to the apparatus main body 10. One end portion of the rotating frame 25 sandwiching the rotating fulcrum provided with the rotating fulcrum pin 27 has an abutting portion 28 that contacts the transfer roller 5, and the other end portion of the rotating frame 25 sandwiching the rotating fulcrum pin is The connecting frame 26 is connected. Further, the other end of the rotary frame 25 is normally biased to the + X side by a spring 25a.

  The contact portion 28 of the rotating frame 25 has a shape cut out into a substantially semicircular shape. As shown in FIGS. 8 and 9, the contact portion 28 is configured to be able to contact a bearing collar 5 a that rotatably supports the transfer roller 5. In addition to the contact portion 28, a hook portion 29 is provided at one end portion of the rotating frame 25 of the present embodiment. The hook portion 29 is disposed at a position where it can contact the transfer guide plate 30 provided on the front side of the transfer roller 5 in the transport direction (see FIG. 9). The transfer guide plate 30 is rotatably provided around a rotation fulcrum 31 as shown in FIGS. Note that the contact portion 28 and the hook portion 29 are disposed with a slight clearance from the transfer roller 5 and the transfer guide plate 30 so that the position accuracy is not affected in a normal state.

  As shown in FIG. 7, the connection frame 26 has a substantially long plate shape, and a first engagement hole 32 that engages the other end of the rotary frame 25 is formed at one end on the + X side. A second engagement hole 34 is formed at the other end on the −X side. The second engagement hole 34 engages with the claw member 33 provided on the rotary shaft 22. The claw member 33 is provided adjacent to the cam member 23. When the claw member 33 moves due to the rotation of the rotation shaft 22, the connecting frame 26 that engages with the claw member 33 moves, and the other end of the rotating frame 25 that engages with the connecting frame 26 moves.

  The movement of the other end of the rotary frame 25 is converted into a movement in the rotation direction by the rotation fulcrum pin 27. That is, the rotation frame 25 rotates about the rotation fulcrum pin 27, so that one end portion thereof swings, and the transfer roller 5 that is in contact with the contact portion 28 provided at the one end portion moves. Further, the transfer guide plate 30 is also moved by the hook portion 29 provided at the one end portion.

  As shown in FIG. 6, the link members 24 are provided in pairs on the rotary shaft 22 with a gap in the Y-axis direction. The link members 24 are provided at positions corresponding to both sides of the transfer roller 5 in the Y-axis direction. That is, the link member 24 is in contact with not only the + Y side end portion of the transfer roller 5 but also the −Y side end portion of the transfer roller 5. Therefore, the transfer roller 5 can move in a stable parallel manner without tilting the shaft by contacting the link member 24 at two points at both ends.

  Subsequently, a unit attaching / detaching operation of the drum unit c3 in the copying machine P having the above configuration will be described.

  When taking out the drum unit c3 from the apparatus main body 10, first, the operator opens the cover 11 provided on the front side of the apparatus main body 10 as shown in FIG. When the cover 11 is opened, the handle portion 12 of the drum unit c3 and the lever member 21 of the operation member 20 are exposed to the front side of the apparatus main body 10 as shown in FIG.

  Next, the operator displaces the operation member 20 from the first position to the second position before pulling the handle portion 12 of the drum unit c3. Specifically, the operator holds the lever member 21 and tilts it from the substantially oblique 45 degree posture shown in FIG. 4 to the substantially horizontal posture shown in FIG. When the lever member 21 is tilted and the operation member 20 is displaced from the first position to the second position, each of the developing unit c2 and the transfer roller 5 is moved from the proximity position to the separation position in conjunction with each other.

  More specifically, when the lever member 21 falls, the rotating shaft 22 connected to the lever member 21 rotates. When the rotating shaft 22 rotates, the tip of the cam member 23 swings, the contact surface 13a is pressed, and the pressing unit 13 moves to the -X side against the biasing force of the pressing spring 14. When the pressing unit 13 moves to the −X side, the pressing on the developing unit c2 is released, and the pressing / positioning of the developing roller 2 on the photosensitive drum 1 is released. The developing unit c <b> 2 moves to the −X side together with the pressing unit 13 through the long hole 16, thereby being positioned at a separated position separated from the photosensitive drum 1.

  Further, when the rotation shaft 22 rotates, the link member 24 is moved together with the cam member 23. Specifically, when the rotating shaft 22 rotates and the claw member 33 rotates, the connecting frame 26 that engages with the claw member 33 is pulled to the −X side, and the other end of the rotating frame 25 that engages with the connecting frame 26. Moves to the -X side against the bias of the spring 25a. The movement of the other end portion of the rotating frame 25 to the −X side is converted into a movement in the rotating direction by the rotating fulcrum pin 27, and one end portion of the rotating frame 25 is opposite to the other end portion, that is, the rotating fulcrum pin 27 is moved. Move to the + X side as the center.

  A contact portion 28 is provided at one end of the rotating frame 25, and the transfer roller 5 is pushed to the + X side against the bias of the pressing spring 17 together with the bearing collar 5 a, so The pressing / positioning of the transfer roller 5 is released. Then, the transfer roller 5 is located at a separated position away from the photosensitive drum 1. In this embodiment, since the transfer guide plate 30 is also arranged at a position close to the photosensitive drum 1, the transfer guide plate 30 is also moved by the hook portion 29 when the transfer roller 5 is positioned at the separated position. 1 so as to be separated from 1.

By displacing the operation member 20 to the second position, two or more members (the developing unit c2, the transfer roller 5, and the transfer guide plate 30) arranged around the photosensitive drum 1 are moved to the separated positions shown in FIG. After being positioned and released, the operator grasps the handle portion 12 shown in FIG. 3 provided above the lever member 21 and pulls out the drum unit c3 to the front side (+ Y side).
At this time, since the two or more members facing the photosensitive drum 1 in a direction other than the drawing direction (Y-axis direction) of the drum unit c3 are separated from the photosensitive drum 1, the drum unit c3 is pulled out in the Y-axis direction. It can be removed from the apparatus main body 10.

  On the other hand, when the drum unit c3 after maintenance or a new drum unit c3 is mounted on the apparatus main body 10, the operator positions the operation member 20 at the second position and moves the drum unit c3 to the apparatus main body 10 with respect to Y. Insert in the axial direction. At this time, when the drum unit c3 is mounted on the apparatus main body 10, since the two or more members facing the photosensitive drum 1 are located at the separated positions as described above, the drum unit c3 is inserted in the Y-axis direction. Then, it can be attached to the apparatus main body 10.

  When the drum unit c3 is inserted, the operator displaces the operation member 20 from the second position to the first position. Specifically, the operator holds the lever member 21 and raises it from a substantially horizontal posture shown in FIG. 5 to a substantially oblique 45 ° posture shown in FIG. When the lever member 21 is raised and the operation member 20 is displaced from the second position to the first position, each of the developing unit c2 and the transfer roller 5 moves from the separated position to the close position in conjunction with each other.

  More specifically, when the lever member 21 is raised, the rotating shaft 22 connected to the lever member 21 rotates. When the rotating shaft 22 rotates, the tip of the cam member 23 swings, the pressure on the contact surface 13 a is released, and the pressing unit 13 moves to the + X side by the urging of the pressing spring 14. When the pressing unit 13 moves to the + X side, the developing unit c2 moves and is pressed, and the developing roller 2 is returned to the proximity position where the developing roller 2 is pressed and positioned with respect to the photosensitive drum 1.

  Further, when the rotation shaft 22 rotates, the link member 24 is moved together with the cam member 23. Specifically, when the rotating shaft 22 rotates and the claw member 33 rotates, the pulling of the other end portion of the rotating frame 25 through the connecting frame 26 to the −X side is released, and the one end portion of the rotating frame 25 is provided. The pressure on the transfer roller 5 by the contact portion 28 is released. The abutting portion 28 moves to the −X side by the urging force of the pressing spring 17 of the transfer roller 5. The contact portion 28 is separated from the transfer roller 5 with a predetermined clearance by the bias of the spring 25 a at the other end of the rotating frame 25. The transfer roller 5 is positioned by the positioning member 35 and the like, and returns to the close position where the transfer roller 5 is pressed and positioned with respect to the photosensitive drum 1 by the biasing force of the pressing spring 17. At this time, the pressing by the hook portion 29 of the transfer guide plate 30 is also released, and the transfer guide plate 30 returns to the original position.

  By displacing the operation member 20 to the first position, two or more members (the developing unit c2, the transfer roller 5, and the transfer guide plate 30) arranged around the photosensitive drum 1 are moved to the close positions shown in FIG. By positioning the drum unit c3, the drum unit c3 is attached to the apparatus main body 10. Thereafter, the operator closes the cover 11 shown in FIG. 3 to complete the attachment of the drum unit c3 to the apparatus main body 10.

  As described above, in the present embodiment, two or more members arranged around the photosensitive drum 1 are interlocked and moved in close proximity by the displacement operation between the first position and the second position of the operation member 20. / Separate is selectively possible. For this reason, if the operation member 20 is displaced from the second position to the first position after replacement of the drum unit c3, the cover 18 (see FIG. 3) on the side of the apparatus body 10 is manually opened and closed as in the prior art. Without equalization, each of the two or more members can be automatically positioned from the separated position to the original proximity position.

Therefore, the operation of attaching / removing the drum unit c3 does not change the direction of the operation by the operator (that is, only the operation from the front side (+ Y side) of the apparatus main body 10), and the operation member 20 can be simplified. This is possible through intuitive operation.
In addition, when the drum unit c3 is set as a user replaceable unit and the user is replaced, forgetting to open the cover 18 when the drum unit c3 is pulled out to the near side or forgetting to close the cover 18 after replacing the drum unit c3. The drum unit can be exchanged securely without any anxiety.

  Therefore, according to the present embodiment, the drum unit c3 having the photosensitive drum 1 that carries the toner image is the copying machine P that is detachably provided in a predetermined direction with respect to the apparatus main body 10, and the drum unit c3 is Two or more members (developing unit c2, transfer roller 5, etc.) disposed opposite to the photosensitive drum 1 in directions other than the predetermined direction when mounted on the apparatus main body 10 are provided. Each of the members is independently provided so as to be movable between a proximity position that is in contact with or close to the photosensitive drum 1 and a separation position that is separated from the photosensitive drum 1. An operation member 2 that is displaceable between a first position that links each of the members to a close position and a second position that links each of the two or more members to a separated position. By adopting a structure of having it relates drum unit c3 replacement work concise, and generally the user can perform a reliable operation definitely.

  As mentioned above, although preferred embodiment of this invention was described referring drawings, this invention is not limited to the said embodiment. Various shapes, combinations, and the like of the constituent members shown in the above-described embodiments are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the above-described embodiment, the developing unit c2, the transfer roller 5, and the transfer guide plate 30 are exemplified as the two or more members, but the present invention is not limited to this configuration. For example, when the charger 3, the cleaner 4 and the like, which are peripheral members of the photosensitive drum 1, are not unitized, these are also included in two or more members so as to be closely moved / separated by the operation member 20. May be.

  Further, for example, in the above embodiment, the drum unit is exemplified as the image carrier unit, but the present invention is not limited to this configuration. For example, a belt unit including an intermediate transfer belt may be employed as the image carrier unit.

  For example, in the above-described embodiment, a copying machine is exemplified as the image forming apparatus, but the present invention is also applicable to an image forming apparatus such as a printer or a facsimile apparatus.

  P: copier (image forming apparatus), 1 ... photosensitive drum (image carrier), 2 ... developing roller, 5 ... transfer roller (two or more members), 10 ... device main body, 14 ... pressing spring (biasing member) , 17 ... Pressing spring (biasing member), 20 ... Operating member, 21 ... Lever member, 22 ... Rotating shaft, 23 ... Cam member, 30 ... Transfer guide plate (two or more members), c2 ... Developing unit, c3 ... Drum unit (image carrier unit)

Claims (4)

An image forming apparatus in which an image carrier unit having an image carrier for carrying a toner image is detachably provided in a predetermined direction with respect to the apparatus main body,
When the image carrier unit is mounted on the apparatus main body, the image carrier unit includes two or more members arranged to face the image carrier in directions other than the predetermined direction, each of the two or more members being Independently, it is movably provided between a proximity position that is in contact with or close to the image carrier and a separation position that is separated from the image carrier,
Displacement between a first position that links each of the two or more members to the close position and a second position that links each of the two or more members to the separated position It has a free operation member,
The two or more members are:
A developing unit having a developing roller for developing the toner image;
A transfer roller for transferring the toner image of the image carrier to a predetermined sheet material,
The operating member is
A rotating shaft to which a lever member is coupled;
A cam member provided on the rotation shaft and configured to move the developing unit between the proximity position and the separation position in accordance with a displacement around the rotation shaft;
A link member connected to the rotation shaft and moving the transfer roller between the proximity position and the separation position in accordance with a displacement around the rotation shaft axis;
The cam members are provided in pairs in the axial direction of the rotary shaft, and the developing unit moves in contact with the cam member at two points. .   The link members are provided in pairs in the axial direction of the rotation shaft, and the transfer roller moves in contact with the link member at two points at both ends. The image forming apparatus according to claim 1. The two or more members further include a transfer guide plate that guides the sheet material between the image carrier and the transfer roller,
The link member is
A contact portion that moves the transfer roller between the proximity position and the separation position in accordance with a displacement around the rotation axis;
The image forming apparatus according to claim 1, further comprising: a hook portion that moves the transfer guide plate between the proximity position and the separation position in accordance with a displacement around the rotation axis.   The contact portion and the hook portion are arranged with a clearance from the transfer roller and the transfer guide plate when the transfer roller and the transfer guide plate are located at the close position. Item 4. The image forming apparatus according to Item 3.

Images