JP5868726B2 - Transfer unit and image forming apparatus - Google Patents

Description

  The present invention relates to a transfer unit mounted on an electrophotographic image forming apparatus and an image forming apparatus including the transfer unit.

  In an electrophotographic image forming apparatus, an image forming process is performed in which a toner image is directly or indirectly transferred from a surface of an image carrier to a sheet by a transfer member. The toner remains on the surface of the image carrier after the image forming process. Residual toner may move and adhere from the surface of the image carrier to the surface of the transfer member. The toner remaining on the surface of the transfer member causes dirt and transfer failure in the next image forming process, and deteriorates the image quality. Therefore, a cleaning member that removes residual toner from the surface of the transfer member, and a conveyance path from a receiving port that receives the toner removed by the cleaning member to a discharge port that directly or indirectly discharges toner to a waste toner box are provided. And a toner conveying unit.

  Here, the paper may cause a jam when passing between the image carrier and the transfer body. In order to facilitate the jam processing, there is a type in which a transfer body is disposed on a door that opens the inside of the apparatus, and the transfer body is separated from an image carrier inside the apparatus by opening the door.

  When the transfer body is separated from the image carrier, the toner transport section entrance moves as the transfer body moves and distortion occurs in the toner transport section, so part of the transport path is divided to eliminate the distortion. There is a need to. When the conveyance path is divided, the toner leaks from the divided portion. Therefore, after the divided portion is closed, the transfer member is separated from the image carrier.

  For example, a cartridge of the image forming apparatus includes a shutter that opens and closes a supply port for supplying toner, a guide member that is detachable below the supply port and guides opening and closing of the supply port by the shutter, (For example, refer to Patent Document 1). The guide member opens the supply port with a shutter when the cartridge is attached to the cartridge, and closes the supply port with the shutter when the guide member is detached from the cartridge.

  By applying the shutter configuration of the cartridge to the toner conveyance path, the dividing portion can be opened and closed by the shutter, and the toner can be prevented from leaking.

JP 2008-233677 A

  However, since the transfer unit vibrates with the vibration at the time of opening and closing the door, even if the divided part is closed by the shutter, the toner remaining in the gap between the divided part and the shutter falls down, and the inside of the apparatus and the apparatus Dirty the installation location.

  An object of the present invention is to provide a transfer unit and an image forming apparatus that can reliably prevent the inside of the apparatus and the installation place of the apparatus from being contaminated.

  The transfer unit according to the present invention includes a transfer member, a cleaning member, a toner transport unit, and a tray, and is movable between a first position inside the image forming apparatus and a second position outside the image forming apparatus. Yes. The transfer body transfers the toner image onto the paper. The cleaning member removes the toner from the surface of the transfer body. The toner transport unit constitutes a transport path through which the toner removed by the cleaning member is transported, and a divided portion where a part of the transport path is divided while the transfer unit moves from the first position to the second position. Have. The saucer is located below the divided portion.

  As the transfer unit moves, the toner transport unit divides a part of the transport path through which the toner removed by the cleaning member is transported. The toner leaking from the divided portion falls on a tray placed below the divided portion.

  In this configuration, the tray is preferably provided with a capturing member on the upper surface for adsorbing and holding the toner. Even if the tray vibrates with the movement of the transfer unit, the toner can be prevented from dropping from the tray, and the interior of the image forming apparatus and the installation location of the image forming apparatus are not soiled.

  In addition, it is preferable that a shutter mechanism that opens and closes the divided portion is provided that closes the divided portion when a part of the transport path is divided. The shutter mechanism can prevent the toner from leaking from the divided portion by closing the divided portion when it is divided at a part of the conveying path of the toner conveying portion.

  A moving mechanism that allows the tray to move horizontally between an exposure position located below the dividing portion and a retreat position retracted from the exposure position, the exposure position being moved along with the movement of the transfer unit to the second position; It is preferable to provide a moving mechanism that moves the tray to the retracted position as the transfer unit moves to the first position.

  The moving mechanism horizontally moves the tray to an exposure position below the divided portion when the transfer path of the toner conveying portion is divided along with the movement of the transfer unit, and the conveying route of the toner conveying portion is divided. Move the pan horizontally to the retracted position when not in use. When a part of the conveying path of the toner conveying unit is divided, the toner leaked from the dividing part falls on the tray, and when the conveying path of the toner conveying unit is not divided, the member arranged at the exposed position Even if there is, there is no interference between the member arranged at the exposed position and the tray located at the retracted position. By moving the saucer between the exposure position and the retracted position, it is possible to contribute to downsizing the placement space of the saucer.

  Further, in the configuration including the urging member that urges the tray in the direction from the retracted position to the exposure position, and the abutting member that is disposed inside the image forming apparatus and abuts the tray, the tray is the first of the transfer unit. In accordance with the movement from the second position to the first position, it is preferable to move from the exposure position to the retracted position by the contact force against the contact member that opposes the biasing force of the biasing member.

  The tray moves from the retracted position to the exposed position by the biasing force of the biasing member as the transfer unit moves from the first position to the second position. Further, the tray comes into contact with the contact member as the transfer unit moves from the second position to the first position, and the contact force against the contact member opposes the urging force of the urging member. To the retreat position. The tray can be moved horizontally between the exposed position and the retracted position with a simple configuration.

  The image forming apparatus of the present invention includes an apparatus main body, a door, an image carrying unit, the transfer unit described above, and a waste toner box. The door opens the inside of the apparatus main body. The image carrying unit is disposed inside the apparatus main body. The waste toner box is disposed inside the apparatus main body, and is directly or indirectly connected to the toner conveyance unit. The transfer unit is disposed on the door, and is located at the first position when the door is closed, and is located at the second position when the door is opened.

  The transfer unit moves so that the transfer unit is positioned inside the image forming apparatus when the door is closed and the transfer unit is positioned outside the image forming apparatus when the door is opened. In accordance with the movement of the transfer unit, the toner transport unit divides a part of the transport path through which the toner removed by the cleaning member is transported. A tray is disposed below the divided portion, and the toner leaking from the divided portion falls on the tray.

  The transfer unit and the image forming apparatus of the present invention can reliably prevent the interior of the apparatus and the installation location of the apparatus from being contaminated.

1 is a schematic front sectional view of a part of an image forming apparatus according to an embodiment of the present invention. FIG. 3 is a perspective view when the door of the transfer unit included in the image forming apparatus is closed. FIG. 3 is a cross-sectional view of a toner transport unit included in the transfer unit. FIG. 3 is a perspective view when the door of the transfer unit is opened.

  As shown in FIG. 1, an image forming apparatus 100 to which a secondary transfer unit (corresponding to a transfer unit of the present invention) 3 according to the first embodiment of the present invention is applied is an external device (not shown) as an example. Multi-color or single-color image forming processing by electrophotography is performed on the paper based on the image data input from. Therefore, the image forming apparatus 100 includes an image forming unit 1, an intermediate transfer unit 2, a secondary transfer unit 3, a fixing unit 4, and a sheet conveyance path S. The apparatus main body (not shown) is provided with an image forming unit 1, an intermediate transfer unit 2, a fixing unit 4, and a paper transport path S. An openable / closable door (not shown) that opens the inside of the apparatus main body is provided. A secondary transfer unit 3 is disposed.

  The image forming unit 1 irradiates image light based on the image data from the exposure unit 11 to form electrostatic latent images on the surfaces of the photosensitive drums 12A to 12D, is supplied with toner, and the electrostatic latent image is converted into a toner image. Visualized.

  The intermediate transfer unit (image carrying unit of the present invention) 2 includes an intermediate transfer belt 21, a driving roller 22, a driven roller 23, a cleaning member 24, and a toner transport unit 25. The intermediate transfer belt 21 is stretched around the driving roller 22 and the driven roller 23, and moves along a circulation path that passes through the photosensitive drums 12D, 12C, 12B, and 12A in this order. Along with this movement, the toner images formed on the surfaces of the photosensitive drums 12A to 12D are primarily transferred onto the surface of the intermediate transfer belt 21. The cleaning member 24 is disposed so that one end thereof is in contact with the surface of the intermediate transfer belt 21, and the toner transport unit 25 is parallel to the axial direction of the driven roller 23 and faces the surface of the intermediate transfer belt 21. It is arranged as follows.

  The secondary transfer unit 3 includes a secondary transfer belt (corresponding to a transfer body of the present invention) 31, a secondary transfer roller 32, a driving roller 33, a driven roller 34, a cleaning member 35, and a toner transport unit 6. The secondary transfer belt 31 is stretched around the secondary transfer roller 32, the drive roller 33, and the driven roller 34, and moves along a predetermined circulation path. The secondary transfer roller 32 is disposed so as to face the drive roller 22 with the intermediate transfer belt 21 and the secondary transfer belt 31 interposed therebetween. The secondary transfer unit 3 secondarily transfers the toner image on the surface of the intermediate transfer belt 21 to a sheet conveyed to a secondary transfer position between the intermediate transfer belt 21 and the secondary transfer belt 31. The cleaning member 35 is disposed so that one end thereof is in contact with the surface of the secondary transfer belt 31.

  Deposits including toner remaining on the surface of the intermediate transfer belt 21 after the secondary transfer and attached paper dust are removed by the cleaning member 24. The removed deposit is indirectly discharged to the waste toner box 5 through the toner transport unit 25 and the toner transport unit 51 along a predetermined transport direction. The waste toner box 5 is disposed inside the apparatus main body, and stores discharged deposits.

  Deposits adhering to the surface of the secondary transfer belt 31 after the secondary transfer are removed by the cleaning member 35. The removed deposit is indirectly discharged to the waste toner box 5 through the toner transport unit 6 and the toner transport section 51 along the predetermined transport direction X. The deposits on the surface of the intermediate transfer belt 21 and the surface of the secondary transfer belt 31 may be directly discharged to the waste toner box 5 without passing through the toner transport unit 51.

  The fixing unit 4 heats and pressurizes the paper on which the toner image is transferred, and firmly fixes the toner image transferred on the paper to the surface of the paper.

  The paper transport path S is formed between a paper feed cassette (not shown) and a secondary transfer position and the fixing unit 4 to reach a paper discharge tray (not shown).

  As shown in FIG. 2, the secondary transfer unit 3 is arranged such that the drive roller 33, the secondary transfer roller 34, and the driven roller 34 are positioned in this order from the top to the bottom in the vertical direction. A roller 32 and a driven roller 34 are disposed. In the secondary transfer roller 32, the drive roller 33, and the driven roller 34, both end portions of the rotation shaft are held by holding members 71 and 72 via bearings (not shown). In the transport direction X, the holding member 71 is located on the downstream side of the secondary transfer belt 31, and the holding member 72 is located on the upstream side of the secondary transfer belt 31.

  The holding members 71 and 72 are attached to the door in a floating state at both ends on the side holding the drive roller 33 via support members 73 and 74 each having a spring 75 which is an elastic member. The support members 73 and 74 are detachably provided on the door.

  Accordingly, since the secondary transfer unit 3 is supported by the door in a floating state, an attachment error of the door to the apparatus main body can be absorbed, and the secondary transfer unit 3 can be accurately positioned. Even if the door vibrates due to the influence of vibration or noise at the installation location, the secondary transfer unit 3 can be accurately positioned without being affected by the vibration of the door. Further, since the support members 73 and 74 are detachable from the door, the secondary transfer unit 3 is also detachable from the door.

  Further, the toner transport unit 6 includes a toner transport unit 60, a discharge port 63, and a shutter 64, and transports the deposits removed from the surface of the secondary transfer belt 31 along the transport direction X.

  The toner transport unit 60 includes a first toner transport unit 61 and a second toner transport unit 62. The first toner conveying portion 61 has a cylindrical shape, and is disposed so that its longitudinal direction coincides with the axial direction of the secondary transfer roller 32 and is opposed and fixed along the surface of the secondary transfer belt 31. . The first toner transport unit 61 is disposed on the lower side in the vertical direction of the secondary transfer belt 31, and receives a deposit (not shown) that receives the deposits removed from the surface of the secondary transfer belt 31 by the cleaning member 35. ) On the top surface in the vertical direction. The first toner transport unit 61 is connected to the downstream end in the transport direction X at the upstream end of the second toner transport unit 62.

  The second toner transport unit 62 extends outward from the downstream end of the secondary transfer belt 31 in the transport direction X. The second toner conveying portion 62 has a flexible cylindrical shape and is freely deformable. The second toner transport unit 62 includes a discharge port 63 at the downstream end in the transport direction X.

  As shown in FIG. 3, a spiral conveyance member 66 is disposed inside the toner conveyance unit 60 so as to be rotatable around a rotation axis parallel to the axial direction of the secondary transfer roller 32. The spiral conveyance member 66 is a member that contacts a part of the inner peripheral surface of the toner conveyance unit 60 by rotation, and conveys the adhered matter along the conveyance direction X by rotating. The spiral conveying member 66 is supplied with rotation from a motor (not shown).

  The spiral conveying member 66 includes a first conveying member 67 and a second conveying member 68 having an upstream end in the conveying direction X connected to a downstream end of the first conveying member 67. The The first conveyance member 67 is a screw having a rotation shaft 671 and a spiral blade 672 provided around the rotation shaft 671, and is disposed inside the first toner conveyance unit 61. The first conveying member 67 always maintains a state in which the axial direction is parallel to the axial direction of the secondary transfer roller 32. The second transport member 68 is a deformable spiral wire rod, and is disposed inside the second toner transport unit 62.

  When the second toner conveying portion 62 is deformed, the second conveying member 68 is deformed so as to maintain a state in contact with a part of the inner peripheral surface. That is, the second conveying member 68 can be deformed according to the deformation of the second toner conveying portion 62. At this time, the first toner conveyance unit 61 and the first conveyance member 67 are not deformed while the axial direction is maintained parallel to the axial direction of the secondary transfer roller 32.

  As described above, since the second conveying member 68 is deformed along with the deformation of the second toner conveying portion 62, the spiral conveying member 66 is in contact with a part of the inner peripheral surface of the toner conveying portion 60 over the entire area. The state can be maintained, and the deposit can be transported to the discharge port 63 without stagnation.

  As shown in FIGS. 2 and 4, the discharge port 63 is an opening formed on the lower surface in the vertical direction, and is detachably provided in the connection port 52 of the toner transport unit 51. The discharge port 63 is attached to the connection port 52 when the door is closed, and is detached from the connection port 52 when the door is opened.

  The connection port 52 is disposed below the discharge port 63 when the door is closed. In the vertical direction, an opening for receiving the toner discharged from the discharge port 63 is formed on the upper surface of the connection port 52, and the lower surface in the vertical direction of the connection port 52 is connected to the toner conveying portion 51 to the waste toner box 5. It is connected. The opening of the connection port 52 is larger than the opening of the discharge port 63.

  The discharge port 63 can be opened and closed by a shutter 64. The shutter 64 has a cylindrical shape and is disposed along the outer surface of the downstream end portion of the second toner conveying portion 62 in the conveying direction X. The shutter 64 has an opening 641 having the same shape as the discharge port 63 on the side surface, and is disposed so as to be rotatable around a rotation axis parallel to the transport direction X. When the opening 641 overlaps the discharge port 63, the shutter 64 opens the overlapping portion of the discharge port 63. When the opening 641 is positioned on the lower surface side in the vertical direction, the shutter 64 coincides with the discharge port 63 and opens the discharge port 63. When the opening 641 is located on the front side (other than the lower surface in the vertical direction), the shutter 64 does not overlap the discharge port 63 and closes the discharge port 63.

  The shutter 64 is rotatable with the opening and closing of the door, and is configured to close the discharge port 63 when the door is opened and open the discharge port 63 when the door is closed. ing. That is, the shutter 64 opens the discharge port 63 with the discharge port 63 attached to the connection port 52, and closes the discharge port 63 with the discharge port 63 detached from the connection port 52.

  A storage unit 80 is disposed on the door. The storage unit 80 moves together with the secondary transfer unit 3 as the door is opened and closed. The storage unit 80 includes a tray 81 and a spring (not shown).

  As the door is opened and closed, the tray 81 moves horizontally between a retracted position stored in the storage unit 80 and an exposed position exposed from the storage unit 80 and below the discharge port 63. It is free. The tray 81 is biased by a spring in a direction from the retracted position toward the exposed position. When the door is opened, the tray 81 moves from the retracted position to the exposed position by the biasing force of the spring. When the door is closed, the tray 81 contacts the connection port 52, and the contact force against the connection port 52 moves from the exposed position to the retracted position against the urging force of the spring.

  The receiving tray 81 is provided with a capturing member 82 on the entire upper surface in the vertical direction. The capture member 82 is a member that is made of a flocking member such as a moquette or suede, or a porous foam member such as a sponge, and adsorbs and holds an adhering substance.

  As a result, even if the secondary transfer unit 3 vibrates due to opening and closing of the door and the adhering matter falls from the gap between the discharge port 63 and the shutter 64, it falls on the tray 81, so that the inside of the image forming apparatus 100. And contamination of the installation place of the image forming apparatus 100 can be prevented. Even if the tray 81 vibrates due to the opening and closing of the door, the deposit that has fallen by the capture member 82 is adsorbed and held, so that the deposit from the tray 81 can be prevented from falling.

  Further, by moving the tray 81 with the opening and closing of the door, the tray 81 is arranged directly below the discharge port 63 when the discharge port 63 is detached from the connection port 52 and moves from above the connection port 52. When the discharge port 63 moves above the connection port 52 and is attached to the connection port 52, the tray 81 and the connection port 52 do not interfere with each other, and the tray 81 is retracted from directly below the discharge port 63. Can be made. By horizontally moving the tray 81, the deposits are less likely to fall from the top of the tray 81.

  In the above-described embodiment, only the first conveying member 67 is disposed in the first toner conveying portion 61, and only the second conveying member 68 is disposed in the second toner conveying portion 62. However, upstream of the first conveyance member 67 and the second conveyance member 68 in the conveyance direction X so that the conveyance member 66 always contacts a part of the inner peripheral surface of the toner conveyance unit 60 when the second toner conveyance unit 62 is deformed. A part of the first conveying unit 61 may be disposed in the first toner conveying unit 61. A part of the first conveying member 67 on the downstream side in the conveying direction X and the second conveying member 68 may be arranged in the second toner conveying unit 62. You may arrange | position in.

  Furthermore, the 1st conveyance member 67 may be comprised from the rod-shaped shaft body which penetrates the inside of a helical wire and a helical wire, and may be comprised from a rigid helical wire. Further, the second toner transport unit 62 may be flexible at least at a part of the downstream side in the transport direction X.

  The above description of the embodiment is to be considered in all respects as illustrative and not restrictive. The scope of the present invention is shown not by the above embodiments but by the claims. Furthermore, the scope of the present invention is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

3 ... secondary transfer unit 6 ... toner transport unit 31 ... secondary transfer belt 35 ... cleaning member 63 ... discharge port 81 ... tray

Claims (6)

A transfer unit movable between a first position inside the image forming apparatus and a second position outside the image forming apparatus;
A transfer body for transferring a toner image to paper;
A cleaning member for removing toner from the surface of the transfer member;
A toner transport unit that forms a transport path through which the toner removed by the cleaning member is transported, and a part of the transport path is moved while the transfer unit moves from the first position to the second position; A toner conveying portion having a divided portion to be divided;
A saucer located below the divided portion ,
The toner conveying portion has a flexible portion extending outward from the downstream end portion of the transfer member in the toner conveying direction, and a deformable spiral wire is disposed in the portion. transfer unit that has been.   The transfer unit according to claim 1, wherein the tray includes a capturing member that adsorbs and holds toner on an upper surface thereof.   3. The transfer unit according to claim 1, further comprising a shutter mechanism that opens and closes the divided portion, and that closes the divided portion when a part of the transport path is divided.   A moving mechanism that allows the tray to move horizontally between an exposure position positioned below the dividing portion and a retracted position retracted from the exposure position, the moving unit being moved to the second position; 4. The apparatus according to claim 1, further comprising a moving mechanism that moves the tray to the exposure position and moves the tray to the retracted position as the transfer unit moves to the first position. The transcription unit described in 1. A biasing member that biases the tray in the direction from the retracted position toward the exposed position;
An abutting member disposed inside the image forming apparatus and against which the saucer abuts,
As the transfer unit moves from the second position to the first position, the tray is moved from the exposed position to the retracted position by a contact force against the contact member against a biasing force of the biasing member. The transfer unit according to claim 4, which moves to. The device body;
A door that opens the inside of the apparatus body;
An image carrier unit;
The transfer unit according to any one of claims 1 to 5,
A waste toner box connected directly or indirectly to the toner conveying unit,
The image carrying unit and the waste toner box are disposed inside the apparatus main body,
The image forming apparatus, wherein the transfer unit is disposed on the door, is located at the first position when the door is closed, and is located at the second position when the door is opened.

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