JP2008164693A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of surely conveying a recording medium even when an image holding body and a conveying member are made away from each other. <P>SOLUTION: The image forming apparatus 10 has: the conveying member 60 formed in belt shape and conveying the recording medium; a plurality of image holding bodies 40 arranged side by side in the conveying direction of the conveying member 60 so as to be opposed to the conveying member 60 and holding images; and a plurality of transfer members 62 respectively arranged to be opposed to the plurality of image holding bodies 40 through the conveying member 60, coming into contact with the conveying member 60 and transferring the image held by the image holding body 40 to the recording medium conveyed by the conveying member 60. In the image forming apparatus 10, one image holding body 40 is opposed to the conveying member 60 and other three image holding bodies 40 are separated from the conveying member 60. In such a case, a pressing member 76 is interposed between the image holding body 40 and the conveying member 60, which are made away from each other, and presses to hold the recording medium conveyed by the conveying member 60 with the transfer member 62 through the conveying member 60. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

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

  As this type of image forming apparatus, an image holding body for holding images of a plurality of colors and a conveying member for conveying a recording member, and a plurality of image holding bodies are arranged side by side in the conveying direction of the conveying member It has been known. In such an image forming apparatus, when a monochrome image is formed, a technique is known in which a black image holding member is opposed to a conveying member, and the other image holding member and the conveying member are separated from each other. ing. Further, if the image holding member and the transport member are separated from each other in this way, the recording medium transported by the transport member may be peeled off from the transport member, or the position with respect to the transport member may be shifted. It is also known to arrange and press against a conveying member (Patent Document 1).

JP 2000-352883 A

  An object of the present invention is to ensure that a recording medium can be conveyed even when the image carrier and the conveying member are separated from each other.

  The present invention according to claim 1 is a belt-shaped conveyance member that conveys a recording medium, and a plurality of image carriers that are arranged side by side in the conveyance direction of the conveyance member so as to face the conveyance member and hold an image. Each of the plurality of image holders is disposed to face each other via the transport member, contacts the transport member, and transfers the image held by the image holder to a recording medium transported to the transport member. When a plurality of transfer members, one image holding member, and the conveying member are in contact with each other and at least one other image holding member is separated from the conveying member, the space between the separated image holding member and the conveying member is And a pressing member that presses the recording medium conveyed by the conveying member between the transfer member and the transfer member via the conveying member.

  According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the image forming apparatus further includes a covering member that covers a portion of the image holding member facing the conveying member, and the pressing member is supported by the covering member. is there.

  The present invention according to claim 3 is the image forming apparatus according to claim 2, wherein the covering member has a guide portion for guiding a recording medium conveyed to the conveying member.

  The present invention according to claim 4 is the image forming apparatus according to claim 2 or 3, wherein the pressing member is supported by the covering member so as to rotate in accordance with the conveyance of the conveyance member.

  According to a fifth aspect of the present invention, the conveying member conveys a recording medium upward in the gravitational direction, and the plurality of image carriers are arranged along the gravitational direction. This is an image forming apparatus.

  The present invention according to claim 6 is a belt-shaped conveyance member that conveys a recording medium, and a plurality of image holders that are arranged side by side in the conveyance direction of the conveyance member so as to face the conveyance member and hold an image. Each of the plurality of image holders is disposed to face each other via the transport member, contacts the transport member, and transfers the image held by the image holder to a recording medium transported to the transport member. A plurality of transfer members, a first state in which all of the plurality of image holding members are in contact with the conveying member, one image holding member and the conveying member are in contact, and at least one other image holding member and the conveying member A switching mechanism that switches to a second state in which the member is separated, and when the switching mechanism is switched to the second state, the switching mechanism is interposed between the separated image carrier and the transport member, Transported to and from the transfer member A pressing member for pressing so as to sandwich the recording medium timber is conveyed, an image forming apparatus having a.

  According to a seventh aspect of the present invention, the first state is a state in which a plurality of colors are formed on a recording medium, and the second state is a state in which a monochrome single color is formed on the recording medium. An image forming apparatus.

  The present invention according to claim 8 is a belt-shaped conveyance member that conveys a recording medium, and a plurality of image holders that are arranged side by side in the conveyance direction of the conveyance member so as to face the conveyance member and hold an image. Each of the plurality of image holders is disposed to face each other via the transport member, contacts the transport member, and transfers the image held by the image holder to a recording medium transported to the transport member. A plurality of transfer members, a first state in which all of the plurality of image holding members are in contact with the conveying member, one image holding member and the conveying member are in contact, and at least one other image holding member and the conveying member A switching mechanism that switches between a second state in which the members are separated from each other and a third state in which all of the plurality of image carriers and the conveying member are separated from each other, and the switching mechanism switches to the second state. The separated image carrier and the conveying member And a pressing member that presses the recording medium conveyed by the conveyance member between the transfer member and the transfer member via the conveyance member, and the switching mechanism switches to the third state, An image forming apparatus having a plurality of covering members that respectively cover portions of the plurality of image holding members facing the conveying member.

  The present invention according to claim 9 is the image forming apparatus according to claim 8, wherein the pressing member is supported by the covering member so as to rotate in accordance with the conveyance of the conveyance member.

  According to a tenth aspect of the present invention, in the image forming apparatus according to the eighth or ninth aspect, the pressing member is provided only with respect to the image holding member that is separated in the second state.

  According to an eleventh aspect of the present invention, there is provided an image forming apparatus main body in which at least the transport member, the image holding member, and the transfer member are incorporated, and the image forming apparatus so as to open the inside of the image forming apparatus main body to the outside. The image according to any one of claims 8 to 10, further comprising an opening / closing member provided on a main body, wherein the switching mechanism switches from the first state or the second state to the third state in conjunction with the opening / closing member. Forming device.

  According to the first aspect of the present invention, it is possible to provide an image forming apparatus capable of reliably transporting a recording medium as compared with a case where the present configuration is not provided.

  According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, the image carrier can be protected from the recording medium being conveyed.

  According to the third aspect of the present invention, in addition to the effect of the first or second aspect, the recording medium can be guided so that the recording medium is sandwiched between the pressing member and the conveying member.

  According to the fourth aspect of the present invention, in addition to the effect of the present invention according to any one of the first to third aspects, the conveyance load of the recording medium can be reduced as compared with the case where the present configuration is not provided. Can do.

  According to the fifth aspect of the present invention, the recording medium can be reliably conveyed even when the recording medium is conveyed upward in the direction of gravity.

  According to the sixth aspect of the present invention, there is provided an image forming apparatus capable of reliably transporting a recording medium even when switched to the second state as compared with the case where the present configuration is not provided. can do.

  According to the seventh aspect of the present invention, in addition to the effect of the sixth aspect of the invention, the recording medium can be reliably conveyed even when an image is formed in monochrome monochrome.

  According to the eighth aspect of the present invention, the recording medium can be reliably conveyed as compared with the case where the present configuration is not provided, and the image carrier is protected in the third state. It is possible to provide an image forming apparatus capable of performing the above.

  According to the ninth aspect of the present invention, in addition to the effect of the present invention according to the eighth aspect, the conveyance load of the recording medium can be reduced as compared with the case where the present configuration is not provided.

  According to the present invention of claim 10, in addition to the effect of the present invention of claim 9, the configuration can be simplified.

  According to the eleventh aspect of the present invention, in addition to the effect of the present invention according to any one of the eighth to tenth aspects, the image holding body can be protected according to the opening / closing of the opening / closing member.

Embodiments of the present invention will be described below. In addition, the following description is only an example in implementing this invention, and this invention is not necessarily limited to the matter demonstrated below, It can change suitably as needed.
1 to 3 show an image forming apparatus 10 according to an embodiment of the present invention. The image forming apparatus 10 includes an image forming apparatus main body 12. A recording medium supply device 14 is disposed below the image forming apparatus main body 12. A discharge unit 16 is disposed above the image forming apparatus main body 12. Is formed.

  The recording medium supply device 14 includes a recording medium storage unit 18, and a large number of recording media are stacked on the recording medium storage unit 18. A feed roll 20 is disposed on the upper end of the recording medium storage unit 18, and a roll 22 is provided facing the feed roll 20. The recording medium at the top of the recording medium storage unit 18 is sent out by the feed roll 20, and the recording medium is rolled and conveyed by the cooperation of the feed roll 20 and the rolling roll 22.

  The recording medium conveyed from the recording medium storage unit 18 is temporarily stopped by a registration roller 24, and is passed between an image carrier unit 26 and a transfer unit 28, which will be described later, and through a fixing device 30 by a discharge roller 32 at a predetermined timing. It is discharged to the discharge unit 16. The fixing device 30 includes a pressure roll and a heating roll, and the developer transferred to the recording medium is fixed to the recording medium by heat and pressure by passing the recording medium between the pressure roll and the heating roll. .

  In the image forming apparatus main body 12, an image carrier unit 26, a transfer unit 28, a power supply unit 34, and a control unit 36 are arranged. In the image carrier unit 26, for example, four image carriers 40 are arranged side by side in the direction of gravity. Around each image carrier 40, a charging device 42 as a charging unit provided with a charging roll for uniformly charging the image carrier 40, and a latent image written on each image carrier 40 is developed with a developer (toner). The developing device 44 as a developing means for developing in step (1), a charge eliminating device 46 for discharging the image carrier 40 after the transfer, and a developer removing means for removing the developer remaining on the image carrier 40 after the transfer. And a cleaning device 48.

  The four developer cartridges 50 are connected to the back side of the image carrier unit 26. Each developer cartridge 50 is detachably attached to the image forming apparatus main body 12 on the side surface of the image forming apparatus main body 12. Each developer cartridge 50 is for yellow, magenta, cyan, and black in order from the bottom, and a developer supply unit 52 and a developer recovery unit 54 are integrated. The developer supply unit 52 is connected to the developing device 44 to supply each color developer to the developing device 44, and the developer collecting unit 54 is connected to the cleaning device 48 to collect each color developer.

  Each of the optical writing devices 56 is composed of a laser exposure device, and is disposed on the back side of the image carrier unit 26 at a position corresponding to each image carrier 40, and is applied to the uniformly charged image carrier 40. A latent image is formed by laser irradiation.

  The transfer unit 28 is on the front side of the image carrier unit 26 and is disposed in the vertical direction so as to face the image carrier unit 26. The transfer unit 28 has a belt-like transport member 60, and the transport member 60 is stretched between two support rolls 58 provided in the vertical direction, and transports the recording medium in the direction of gravity. In addition, the transfer unit 28 is provided with a roll-shaped transfer member 62 so as to face each image carrier 40 with the conveying member 60 interposed therebetween. These transfer members 62 are urged to press the back surface of the transport member 60 and are in contact with the back surface of the transport member 60. These transfer members 62 are applied with a potential having a polarity opposite to that of the developer held on the image holding body 40, and the developer held on the image holding body 40 is transferred to the recording medium conveyed by the conveying member 60. .

A first tension roll 64 is disposed on the upstream side (lower side) of the yellow transfer member 62 disposed on the lowermost side, and the black transfer member 62 disposed on the uppermost side and the black transfer member 62 are disposed on the black side. A second tension roll 66 is disposed between the cyan transfer member 62 and the cyan transfer member 62. The first tension roll 64 and the second tension roll 66 are in contact with the back surface of the transport member 60 and support the transport member 60 so that a predetermined tension is applied to the transport member 60. Further, three auxiliary rolls 68 are in contact with the back surface on the opposite side of the conveying member 60 so as to face the transfer members 62 for yellow, magenta, and cyan.
A charge imparting member (not shown) that imparts a charge to the recording medium is provided on the upstream side of the inlet portion of the conveying member 60, and a potential difference is provided between the recording medium and the conveying member 60 so that the recording medium can be used. It is attracted to the conveying member 60.

  The opening / closing member 70 is provided in the image forming apparatus main body 12 so as to rotate via an opening / closing member support shaft 72. As shown in FIG. 3, the opening / closing member 70 is opened and closed integrally with the transfer unit 28. By opening the opening / closing member 70, the jammed recording medium is removed, and the image carrier unit 26 is formed with an image. It is intended to be detachable from the apparatus main body 12.

  As shown in FIG. 1, the state in which all of the four image carriers 40 are in contact with the conveying member 60 so as to face the conveying member 60 is the first state, which is the full color mode. In this first state, a full-color image is formed on the recording medium that is transported by the transport member 60 by driving all of the image carriers 40.

  As shown in FIG. 2, the yellow, magenta, and cyan image holders 40 are separated from the transport member 60, and only the black image holder 40 faces the transport member 60 and contacts the transport member 60. The state is the second state and the monochrome single-color mode. In this second state, the driving of the image carrier 40 is stopped for yellow, magenta and cyan, and only the black image carrier 40 is driven, and a monochrome image is formed on the conveyed recording medium. Is done. In order to separate the image carrier 40 from the conveying member 60 for yellow, magenta, and cyan, a transfer member 40 for yellow, magenta, and cyan, a first tension roll 64, a second tension roll 66, and an auxiliary roll 68 are provided. It moves in a direction away from the image carrier 40. The auxiliary roll 68 is also moved in order to keep the circumference of the conveying member 60 constant.

In this second state, the surface on the conveying member 60 side of the image carrier 40 is covered with the covering member 74 for yellow, magenta, and cyan. Further, as shown in FIG. 4, the covering member 74 is provided with a pressing member 76. For example, four pressing members 76 are provided in the axial direction of the image holding body 40 and are rotatably supported by the covering member 74 so as to protrude toward the conveying member 60 side of the covering member 74. The pressing member 76 is interposed between the image carrier 40 and the conveying member 60 which are separated from each other. The pressing member 76 is driven to rotate as the conveying member 60 moves, and transfer members for yellow, magenta and cyan are conveyed via the conveying member 60. A recording medium conveyed by the conveying member 60 is pressed between the recording medium 62 and the recording medium 62. Further, a guide portion 78 is formed in the axial direction of the image carrier 40 at a portion of the covering member 74 on the upstream side of the pressing member 76. The guide portion 78 is formed to protrude toward the transport member 60 and guides the recording medium so that the transported recording medium does not peel from the transport member 60.
In this embodiment, the pressing member 76 is configured to rotate following the movement of the conveying member 60. However, as another embodiment, the pressing member 76 is fixed to the covering member 74. Can be configured. Further, the covering member 74 can be omitted.

  As shown in FIG. 3, the state where all the four image carriers 40 are separated from the conveying member 60 in conjunction with the opening / closing member 70 is the third state. In this third state, in addition to the yellow, magenta, and cyan image carriers 40, the surface of the black image carrier 40 on the side of the conveying member 60 is covered with the covering member 74. However, the covering member 74 is not provided with a pressing member.

The first state, the second state, and the third state described above are switched by the switching mechanism.
5 to 9, a first specific example relating to the switching mechanism 80 is shown.
As shown in FIGS. 7 to 9, the transfer unit 26 has a transfer unit main body 82, and the above-described support roll 58 is rotatably supported by the transfer unit main body 82. A support shaft of the upper support roll 58 is supported by the transfer unit main body 82 so as to be movable in the vertical direction with respect to the transfer unit main body 82, and there is a first gap between the support roll 58 and the transfer unit main body 82. One urging member 83 is provided. The first urging member 83 is, for example, a tension spring, and urges the upper support roll 58 upward to apply tension to the transport member 60. On the other hand, the lower support roll 58 is connected to a drive source and rotates to drive the transport member 60.

  A support member 84 is provided in the transfer unit main body 82 so as to be movable in a direction orthogonal to the transport direction of the transport member 60. The support member 84 supports a transfer member 62 for yellow, magenta, and cyan, a first tension roll 64, a second tension roll 66, and an auxiliary roll 68 (not shown in FIGS. 5 to 9). Yes. Cams 86, 86 are provided between the transfer unit main body 82 and the support member 84. The cams 86, 86 are connected to a drive source such as a motor, and move the support member 84 in a direction orthogonal to the transport direction of the transport member 60. In addition, second urging members 88, 88 are provided between the transfer unit main body 82 and the support member 84. The second urging members 88 and 88 are, for example, pressing springs, and urge the support member 84 in the direction of the conveying member 60. In the first state shown in FIG. 7, the cams 88 and 88 are at bottom dead center, and the support member 84 is urged by the second urging members 88 and 88 to transfer yellow, magenta, and cyan. The member 62 comes into contact with the image carrier 40 with the conveying member 60 interposed therebetween. When the cams 88, 88 are rotated to the top dead center from this state, the support member 84 moves away from the conveying member 60 against the second urging members 88, 88, and yellow, magenta, and cyan are used. The image holding body 40 and the conveying member 60 are separated from each other, and the second state shown in FIG. 8 can be obtained. Further, the support member 84 is formed with an abutting portion 90 so as to be opposed to a distal end of a driving member 94 described later.

  The image carrier unit 26 is provided with an image carrier support portion 92, and the image carrier 40 is rotatably supported by the image carrier support portion 92. A driving member 94 is provided on the image carrier support portion 92 so as to be slidable in a direction orthogonal to the conveying direction of the conveying member 60. That is, the image carrier support portion 92 is provided with first guide pins 96 and second guide pins 98 arranged in a direction perpendicular to the transport direction of the transport member 60, and the drive member 94 includes A first guide groove 100 and a second guide groove 102 that are long in a direction orthogonal to the conveyance direction of the conveyance member 60 are formed in a direction orthogonal to the conveyance direction of the conveyance member 60, and the first guide pin 96 The second guide pin 98 is engaged with the first guide groove 100 and the second guide groove 102, and the drive member 94 includes the first guide pin 96, the second guide pin 98, and the first guide groove 98. It is slidable with respect to the image carrier support portion 92 via the guide groove 100 and the second guide groove 102.

  A third urging member 104 is provided between the image carrier support portion 92 and the drive member 94. The third urging member 104 is, for example, a tension spring, and urges the driving member 94 so that the tip of the driving member 94 contacts the abutting portion 90 described above.

  In addition, the covering member support shaft 106 is rotatably provided on the image carrier support portion 92. A first connecting member 108 and a second connecting member 110 are fixed to the covering member support shaft 106. The first connecting member 108 is provided with a third guide pin 112, and the third guide pin 112 is engaged with a third guide groove 114 formed in the image carrier support portion 92. A buffer member 116 is disposed in the third guide groove 114, and this buffer member 116 causes a buffering action when the covering member 74 covers the image holding body 40.

  The distal end of the second connecting member 110 is connected to the covering member 74. A fourth guide pin 118 is provided at the other end of the covering member 74. On the other hand, a fourth guide groove 120 is formed in the image carrier support portion 92, and a fourth guide pin 118 is engaged with the fourth guide groove 120. The first connecting member 108 is provided with a fifth guide pin 122. On the other hand, a fifth guide groove 124 is formed in the drive member 94, and the fifth guide pin 122 is engaged with the fifth guide groove 124.

  In the first state shown in FIG. 7, since the support member 84 is urged toward the image carrier 40 by the second urging member 88, all the transfer members 62 are conveyed to the image carrier 40. The contact is made through the member 60. Further, since the abutting portion 90 is located near the image holding body 40, the driving member 94 whose tip is abutted against the abutting portion 90 is in a position retracted against the third urging member 104, The covering member 74 is pulled through the fifth guide groove 124, the fifth guide pin 122, and the second connecting member 110, and the covering member 74 and the pressing member 76 are fixed at positions away from the image carrier 40. .

  Here, when the abutting member 90 moves in the direction A in FIG. 5, the driving member 94 maintains a state where the tip of the driving member 94 abuts against the abutting portion 90 by the urging force of the third urging member 104. Move in direction A. As a result, the fifth guide pin 122 is pressed by the fifth guide groove 124, and the first connecting member 108 and the second connecting member 110 rotate counterclockwise with the covering member support shaft 106 as a fulcrum. When the second connecting member 110 rotates counterclockwise, the fourth guide pin 118 is guided by the fourth guide groove 120, and the covering member 74 moves so as to cover the open portion of the image holding body 40. Then, the pressing member 76 moves to a position where the conveying member 60 is sandwiched between the pressing member 76 and the transfer member 60, and the second state shown in FIG.

  In the third state shown in FIG. 9, since the transfer unit 26 is separated from the black image carrier 40, the tip of the drive member 94 is separated from the abutting portion 90, and the drive member 94 is subjected to the third urging force. The member 104 moves to the conveying member 60 side by the urging force of the member 104. Accordingly, the covering member 74 is moved by the driving member 94, and the open portion of the image carrier 40 is covered by the covering member 74.

10 to 12, a second specific example regarding the switching mechanism 80 is shown.
In the second specific example, the first cam member 126 and the second cam member 128 are provided in the above-described image carrier unit so as to be slidable in the vertical direction. The first cam member 126 is engaged with the cams 86 described above. Further, the first cam member 126 is urged upward by a fourth urging member 130 which is, for example, a compression spring. The upper end of the second cam member 128 is restricted by the upper end of the restricting portion 132 provided in the transfer unit main body, and the second cam member 128 is restricted upward by the fifth biasing member 134 that is a compression spring, for example. Is being energized.

  In the first cam member 126, sixth guide grooves 136 are formed corresponding to the covering members 74 for yellow, magenta, and cyan, respectively. The covering member 74 for yellow, magenta, and cyan is provided with a sixth guide pin 138, and the sixth guide pin 138 engages with the sixth guide groove 136, respectively.

A seventh guide groove 140 is formed in the second cam member 128 corresponding to the black covering member 74. The black covering member 74 is provided with a seventh guide pin 142, and the seventh guide pin 142 is engaged with the seventh guide groove 140.
A third tension roll 144 is provided above the black transfer member 62.

  In the first state shown in FIG. 10, since the support member 84 is urged toward the image carrier 40 by the second urging member 88, all the transfer members 62 are conveyed to the image carrier 40. The contact is made through the member 60. Further, since the first cam member 126 is pressed by the cams 86 and 86 and is in the lower position, and the second cam member 128 is restricted by the restriction portion 132 and is in the lower position, all the covering member covering members 74 and The pressing member 76 is fixed at a position away from the image holding body 40.

  Here, when the cams 86 and 86 are rotated 90 ° counterclockwise from the position of FIG. 10, the support member 84 moves against the second urging member 88 in a direction away from the image holding body 40. The magenta and cyan image carriers 40 and the conveying member 60 are separated from each other. Further, the first cam member 126 is pressed by the fourth urging member 130 and moves upward. When the first cam member 126 moves upward, the covering member 74 and the pressing member 76 for yellow, magenta, and cyan are moved counterclockwise via the sixth guide groove 136 and the sixth guide pin 138. As a result, the covering member 74 moves so as to cover the open portion of the image holding member 40, and the pressing member 76 moves to a position where the conveying member 60 is sandwiched between the pressing member 76 and the second member shown in FIG. It becomes a state.

  In the third state shown in FIG. 12, the restricting portion 132 of the transfer unit 26 is separated from the second cam member 128, so that the second cam member 128 is pressed by the fifth biasing member 134 and moved upward. Move to. When the second cam member moves upward, the black covering member 74 is moved counterclockwise via the seventh guide groove 140 and the seventh guide pin 142. As a result, the covering member 74 moves so as to cover the open portion of the image carrier 40.

  In the second specific example, the first cam member and the second cam member are driven by the urging member. However, the present invention is not limited to this. In conjunction with the movement of the body unit 26, various driving means such as a cam or a rack and pinion can be used. In the first and second specific examples, the lower support roll 58 is connected to the drive source and rotates to drive the conveying member 60. However, even if the upper support roll 58 is driven, Good. In this case, the recording medium conveying surface is on the side where the tension of the conveying member 60 is high, which is preferable for conveying the recording medium.

1 is a side view of an image forming apparatus according to an embodiment of the present invention and shows a first state (full color mode). FIG. 3 is a side view of the image forming apparatus according to the embodiment of the present invention, showing a second state (monochrome monochrome mode). It is a side view of the image forming apparatus which concerns on embodiment of this invention, and shows a 3rd state (open state). It is a perspective view which shows the image holding body, the coating | coated member, and pressing member which were used for embodiment of this invention. 1 is a side view showing a periphery of a yellow image carrier, which is a first specific example of a switching mechanism used in an embodiment of the present invention, and shows a first state. FIG. FIG. 4 is a side view showing a periphery of a yellow image carrier, which is a first specific example of a switching mechanism used in the embodiment of the present invention, and shows a second state. It is a 1st example of the switching mechanism used for embodiment of this invention, is a side view which shows the whole, and shows a 1st state. It is a 1st example of the switching mechanism used for embodiment of this invention, is a side view which shows the whole, and shows a 2nd state. It is a 1st example of the switching mechanism used for embodiment of this invention, is a side view which shows the whole, and shows a 3rd state. It is a 2nd example of the switching mechanism used for embodiment of this invention, is a side view which shows the whole, and shows a 1st state. It is a 2nd example of the switching mechanism used for embodiment of this invention, is a side view which shows the whole, and shows a 2nd state. It is a 2nd example of the switching mechanism used for embodiment of this invention, is a side view which shows the whole, and shows a 3rd state.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 12 Image forming apparatus main body 26 Image holding body unit 28 Transfer unit 40 Image holding body 60 Conveying member 62 Transfer member 70 Opening / closing member 74 Cover member 76 Pushing member 78 Guide part 80 Switching mechanism 83 1st biasing member 88 Second urging member 90 Abutting portion 94 Drive member 104 Third urging member 126 First cam member 128 Second cam member 130 Fourth urging member 132 Restricting portion 134 Fifth urging member

Claims (11)

A conveying member that is formed in a belt shape and conveys a recording medium;
A plurality of image holders that are arranged in the conveying direction of the conveying member so as to face the conveying member, and hold images.
A plurality of image holders arranged opposite to each other via the conveying member, in contact with the conveying member, and transferred to a recording medium conveyed by the conveying member to an image held by the image holding member A transfer member;
When one image carrier and the conveying member are in contact with each other and at least one other image carrier and the conveying member are separated, the image carrier is interposed between the separated image holding member and the conveying member, and the conveying A pressing member that presses the recording medium that is conveyed by the conveying member between the transfer member and a member via the member;
An image forming apparatus.   The image forming apparatus according to claim 1, further comprising a covering member that covers a portion of the image holding member facing the conveying member, and the pressing member is supported by the covering member.   The image forming apparatus according to claim 2, wherein the covering member includes a guide unit that guides a recording medium conveyed to the conveying member.   The image forming apparatus according to claim 2, wherein the pressing member is supported by the covering member so as to rotate according to the conveyance of the conveyance member.   The image forming apparatus according to claim 1, wherein the conveying member conveys a recording medium upward in a gravitational direction, and the plurality of image holding bodies are arranged along the gravitational direction. A conveying member that is formed in a belt shape and conveys a recording medium;
A plurality of image holders that are arranged in the conveying direction of the conveying member so as to face the conveying member, and hold images.
A plurality of image holders arranged opposite to each other via the conveying member, in contact with the conveying member, and transferred to a recording medium conveyed by the conveying member to the image held by the image holding member A transfer member;
A first state in which all of the plurality of image holding members are in contact with the conveying member, a first image holding member and the conveying member are in contact, and at least one other image holding member and the conveying member are separated from each other. A switching mechanism for switching between two states;
When switched to the second state by this switching mechanism, a recording medium that is interposed between the separated image carrier and the transport member and is transported between the transfer member and the transfer member via the transport member A pressing member that presses to sandwich
An image forming apparatus.   The image forming apparatus according to claim 6, wherein the first state is a state in which a plurality of colors are formed on a recording medium, and the second state is a state in which a monochrome monochrome is formed on the recording medium. A conveying member that is formed in a belt shape and conveys a recording medium;
A plurality of image holders that are arranged in the conveying direction of the conveying member so as to face the conveying member, and hold images.
A plurality of image holders arranged opposite to each other via the conveying member, in contact with the conveying member, and transferred to a recording medium conveyed by the conveying member to the image held by the image holding member A transfer member;
A first state in which all of the plurality of image holding members are in contact with the conveying member, a first image holding member and the conveying member are in contact, and at least one other image holding member and the conveying member are separated from each other. A switching mechanism that switches between a second state and a third state in which all of the plurality of image carriers and the conveying member are separated from each other;
When switched to the second state by this switching mechanism, a recording medium that is interposed between the separated image carrier and the transport member and is transported between the transfer member and the transfer member via the transport member A pressing member that presses to sandwich
When the switching mechanism is switched to the third state, a plurality of covering members that respectively cover portions facing the conveying members of the plurality of image holding members,
An image forming apparatus.   The image forming apparatus according to claim 8, wherein the pressing member is supported by the covering member so as to rotate in accordance with the conveyance of the conveyance member.   The image forming apparatus according to claim 8, wherein the pressing member is provided only with respect to the image holding member that is separated in the second state.   An image forming apparatus main body in which at least the conveying member, the image holding member, and the transfer member are incorporated, and an opening / closing member provided in the image forming apparatus main body so as to open the inside of the image forming apparatus main body to the outside. The image forming apparatus according to claim 8, further comprising a switching mechanism that switches from the first state or the second state to the third state in conjunction with the opening / closing member.

Images