JP2020196617A - Cleaning device and image formation apparatus having the same - Google Patents

Abstract

To provide a cleaning device which can contact the surface of a conveyance roller for conveying a sheet without applying an excessive load onto the surface and can clean the surface, and an image formation apparatus having the same.SOLUTION: A cleaning device 7 comprises: a cleaning unit 70; and a movement mechanism 75. The cleaning unit 70 has a pair of unit fulcrum pins 70P. The movement mechanism 75 includes a pair of rotation levers 454 which rotatably supports the pair of unit fulcrum pins 70P and moves the cleaning unit 70 between the cleaning position and the attachment/detachment position following the rotation of the rotation levers 454. At the cleaning position, the cleaning unit 70 contacts a positioning part 102S and the cleaning unit 70 can clean a register lower roller 32. At the attachment/detachment position, the cleaning unit 70 can be attached/detached to/from an apparatus body 10.SELECTED DRAWING: Figure 2

Description

The present invention relates to a cleaning device and an image forming device including the cleaning device.

In an image forming apparatus such as a printer, a sheet is conveyed to a predetermined image forming position, and an image is formed on the sheet at the image forming position. Conventionally, a resist roller pair that feeds a sheet to an image forming position has been known. Each of the resist roller pairs has a length corresponding to the width of the sheet, and forms a nip portion through which the sheet passes. When the tip of the sheet comes into contact with the nip while the rotation of the resist roller pair is stopped, the skew of the sheet is corrected. After that, when the resist roller pair rotates, the sheet is carried into the nip portion, and then the sheet is sent out (conveyed) at an appropriate image formation timing at the image formation position.

Patent Documents 1 and 2 disclose a cleaning device that removes paper dust adhering to the surface of a resist roller. The cleaning device has a web wound in a roll shape and a pressing roller that presses the web against the surface of the resist roller, and the web is sequentially sent out so that a new web surface comes into contact with the surface of the resist roller. And remove the paper dust.

Japanese Unexamined Patent Publication No. 2004-345805 Japanese Unexamined Patent Publication No. 2006-117420

In the techniques described in Patent Documents 1 and 2, the pressing roller presses the web against the lower resist roller of the resist roller pair, and the web cleans the surface of the resist roller. In the resist roller pair, the nip loads of each other need to be properly managed in order to feed the sheet. If the pressing roller presses the web against the lower resist roller too strongly in order to improve the cleanability of the surface of the resist roller, the nip load of the resist roller pair fluctuates, making it difficult to properly feed the sheet. was there. Further, such a problem may occur not only in the resist roller pair but also in the transport roller for transporting the sheet. If paper dust or toner adheres to the surface of the transport roller, poor transport of the sheet or stain of the toner on the sheet occurs, so it is necessary to clean the transport roller. Then, if a cleaning member such as a web abuts too strongly on the transport roller, the transport roller is deformed and its transport function is deteriorated.

The present invention has been made in view of such circumstances, and an object of the present invention is to contact the surface of a transport roller that transports a sheet without applying an excessive load, and to clean the surface thereof. It is an object of the present invention to provide a possible cleaning device and an image forming device including the same.

The cleaning device according to one aspect of the present invention is a cleaning device that is rotatably supported by the main body of the image forming device and can clean the surface of a transport roller that transports a sheet, and is a shaft of the transport roller. Cleaning having a cleaning portion having a contact surface extending along a direction and having the contact surface abutting against the surface of the transport roller from below to clean the surface, and a cleaning housing supporting the cleaning portion. A moving mechanism capable of moving the unit and the cleaning unit between a cleaning position and a attachment / detachment position below the cleaning position. At the cleaning position, the cleaning unit comes into contact with the transport roller. The moving mechanism and the device, which allow the cleaning unit to be disposed downward with respect to the transport roller and the cleaning unit to be attached to and detached from the device main body at the attachment / detachment position. The cleaning unit is arranged at a position different from that of the transport roller in the main body, and abuts on the cleaning unit moved to the cleaning position by the moving mechanism to regulate the positions of the cleaning unit and the transport roller. A positioning unit for positioning the cleaning unit so that the transport roller can be cleaned is provided.

According to this configuration, the cleaning device has a cleaning unit and a moving mechanism to clean the surface of the transport roller. The moving mechanism can move the cleaning unit between the cleaning position and the attachment / detachment position. When the moving mechanism places the cleaning unit in the cleaning position, the positioning unit regulates the relative position between the cleaning unit and the transport roller so that the cleaning unit of the cleaning unit can clean the transport roller, while the moving mechanism cleans the cleaning unit. When placed in the attachment / detachment position, the cleaning unit is separated from the transport roller and the cleaning unit can be attached / detached to / from the device body. As a result, the cleaning unit can be detached from the apparatus main body without imposing a load on the transport roller. Further, since the positioning portion is arranged at a position different from that of the transport roller at the cleaning position, the pressing force of the cleaning portion is compared with the case where another positioning portion is provided at the portion where the cleaning portion and the transport roller are in direct contact with each other. Is prevented from being excessively applied to the transport roller.

In the above configuration, the cleaning housings are arranged so as to face each other in the axial direction of the transport roller and project from a pair of wall portions supporting the cleaning portion and the outer surfaces of the pair of wall portions in the axial direction. It is desirable that the positioning portion has a pair of columnar guide members to be provided, and the positioning portion has an inner peripheral surface along the outer peripheral surface of the pair of guide members and is composed of a recess for receiving the guide member.

According to this configuration, the outer peripheral surface of the guide member is fitted into the positioning portion formed of the recess, so that the relative position between the cleaning portion and the transport roller can be stably regulated.

In the above configuration, the cleaning housing further has a pair of housing shafts projecting in the axial direction from the outer surfaces of the pair of wall portions at positions different from the pair of guide members, and the movement. The mechanism may support the cleaning housing so as to sandwich the cleaning housing from both sides in the axial direction, which is arranged in the unit housing portion and the unit housing portion that accommodates the cleaning unit arranged at the attachment / detachment position. A pair of possible support members, the pair of support members each having a shaft support that receives the housing shaft and rotatably supports the housing shaft, and the pair of housing shafts. The cleaning unit is arranged above the shaft support and parallel to the axial direction so that the cleaning unit moves between the cleaning position and the attachment / detachment position while the portions are pivotally supported by the pair of shaft support. A rotation drive unit that rotates the pair of support members around the first central axis, and the rotation drive unit is such that the cleaning unit maintains a posture in which the cleaning unit faces upward. It is desirable to have a rotation drive unit that rotates the pair of support members while allowing the housing shaft portion to rotate relative to the pair of shaft support portions.

According to this configuration, the rotation drive unit only rotates the pair of support members around the first central axis.
The cleaning unit can be moved between the attachment / detachment position and the cleaning position. At this time, the cleaning unit can maintain the posture in which the cleaning portion faces upward by rotating the pair of housing shaft portions relative to the pair of shaft support portions. Therefore, when the cleaning unit reaches the cleaning position, the cleaning unit can quickly come into contact with the transport roller from below.

In the above configuration, the cleaning housing is supported by the pair of wall portions above the housing shaft portion, and includes a pair of outer peripheral surfaces that are rotatable around a second central axis parallel to the axial direction. Further having a guide roller, the moving mechanism is one end side in a width direction orthogonal to and horizontal to the axial direction of the cleaning unit arranged at the attachment / detachment position, and is spaced apart from each other in the axial direction. In addition, each of the pair of guide portions is arranged so as to extend in the vertical direction, and allows the pair of guide rollers to come into contact with each other as the pair of support members rotate around the first central axis. It is desirable to further have a pair of guide portions that guide the cleaning unit between the cleaning position and the attachment / detachment position.

According to this configuration, the cleaning housing has a pair of guide rollers. Therefore, the cleaning unit can be stably guided between the attachment / detachment position and the cleaning position by the pair of guide rollers and the pair of guide portions in response to the rotation of the pair of support members by the rotation drive portion. ..

In the above configuration, with the cleaning unit arranged at the attachment / detachment position, the pair of support members are arranged so as to extend downward from the first central axis, and the shaft support portion is the support member among the support members. The side portion on the one end side in the width direction has a shape cut out on the other end side opposite to the one end side in the width direction and downward, and the housing shaft portion is orthogonal to the axial direction. Accepted along the direction, the rotation drive unit supports the pair of supports so that the housing shaft portion moves upward and one end side in the width direction from the state where the cleaning unit is arranged at the attachment / detachment position. It is desirable to move the cleaning unit to the cleaning position by rotating the member around the first central axis.

According to this configuration, at the attachment / detachment position, the pair of housing shafts of the cleaning housing can be easily taken in and out of the shaft support of the pair of support members along the direction orthogonal to the axial direction. Further, the cleaning unit can be stably moved to a cleaning position above the attachment / detachment position in a state where the pair of housing shaft portions are fitted into the shaft support portions of the pair of support members.

In the above configuration, when the cleaning unit arranged at the attachment / detachment position is viewed from a direction parallel to the axial direction, the center of the housing shaft portion supported by the shaft support portion is below the first central axis and The cleaning unit is arranged on the one end side in the width direction, the center of gravity of the cleaning unit is arranged on the one end side in the width direction with respect to the housing shaft portion, and the cleaning unit is rotated from the state of being arranged in the attachment / detachment position. When the drive unit rotates the pair of support members around the first central axis, the cleaning unit tilts toward one end side in the width direction about the housing shaft portion due to the weight of the cleaning unit. It is desirable that the pair of guide rollers come into contact with the pair of guide portions.

According to this configuration, when the rotation drive unit rotates the pair of support members around the first central axis at the attachment / detachment position, the cleaning unit tilts by its own weight, and the pair of guide rollers hit the pair of guide portions, respectively. Get in touch. Therefore, the cleaning unit can be stably moved from the attachment / detachment position to the cleaning position by the rotation drive unit without requiring another drive mechanism for bringing the pair of guide rollers into contact with the pair of guide portions.

In the above configuration, the cleaning housing is made of a magnetic material, has a connecting wall that connects the pair of wall portions along the axial direction, and the unit accommodating portion is the cleaning arranged at the attachment / detachment position. It is desirable to have at least one magnetic member that is located opposite the connecting wall of the housing and generates a magnetic field that holds the cleaning unit.

According to this configuration, at least one magnetic member generates a magnetic field that holds the cleaning unit at the attachment / detachment position. Therefore, the magnetic binding force of the magnetic member prevents the cleaning unit from falling out of the unit housing portion.

In the above configuration, the connecting wall of the cleaning housing is a bottom wall defining the bottom of the cleaning housing, and the at least one magnetic member is the bottom wall of the cleaning unit arranged at the attachment / detachment position. When the cleaning unit arranged at the attachment / detachment position is viewed from a direction parallel to the axial direction, the center of the magnetic member in the width direction is the housing supported by the shaft support portion. It is desirable that the shaft portion is arranged on the one end side in the width direction with respect to the center of the shaft portion.

According to this configuration, when the rotation driving unit rotates a pair of support members, the bottom portion of the cleaning unit is tilted to reduce the influence of the magnetic binding force of the magnetic member on the bottom portion, thereby making the cleaning unit. It can be easily moved toward the cleaning position.

In the above configuration, the cleaning unit includes a strip-shaped web having an abutting surface capable of contacting the transport roller, a pressing roller that presses the web against the transport roller, and the transport roller of the web. It has a feeding roller for feeding the web and a winding roller for winding the web so that the portion abutting the web changes, and is connected to the cleaning unit arranged at the cleaning position, and the feeding roller and the said It is desirable to further include at least a web drive mechanism for rotationally driving the take-up roller among the take-up rollers.

According to this configuration, the surface of the transport roller can be stably cleaned by the strip-shaped web. Further, even if the surface of the web becomes dirty, the web can be moved by the rotation of the take-up roller, and the surface of the transport roller can be cleaned by the new contact surface.

In the above configuration, the moving mechanism can move the cleaning unit to a separation position between the cleaning position and the attachment / detachment position in addition to the cleaning position and the attachment / detachment position. It is desirable that the cleaning unit is arranged downward with respect to the transport roller and the connection between the cleaning unit and the web drive mechanism is released.

According to this configuration, when the image is formed under the condition that the surface of the transport roller is not easily soiled, the cleaning unit is arranged at a separated position, so that the load of the transport roller is caused by the cleaning unit coming into contact with the transport roller. It is possible to suppress unnecessary feeding of the web while reducing the number of images.

The image forming apparatus according to another aspect of the present invention includes an apparatus main body, a conveying roller that conveys a sheet, an image forming portion that forms an image on the sheet, and any of the above that can clean the conveying roller. The cleaning device according to the above 1 is provided.

According to this configuration, when the moving mechanism places the cleaning unit in the cleaning position, the cleaning unit of the cleaning unit can clean the transport roller, while when the moving mechanism places the cleaning unit in the detachable position, the cleaning unit is placed in the device body. On the other hand, it can be attached and detached. Therefore, it is possible to stably form an image in the image forming apparatus while stably cleaning the surface of the conveying roller.

In the above configuration, the transport portion that transports the sheet at a position different from that of the transport roller is included, and can be mounted on the apparatus main body along a first direction parallel to the axial direction and opposite to the first direction. A transport unit that can be detached from the apparatus main body is further provided along the second direction of the above, the unit accommodating portion is arranged in the transport unit, and when the cleaning unit is arranged in the detachable position, the cleaning unit is arranged. It is desirable that the device body can be mounted and detached integrally with the transport unit.

According to this configuration, the cleaning unit can be easily attached to and detached from the apparatus main body as well as the attachment and detachment of the conveying unit for conveying the sheet to the apparatus main body.

In the above configuration, when the cleaning unit is integrally detached from the apparatus main body together with the transport unit, a part of the drive transmission system between the rotation drive unit and the pair of support members is cut off. It is desirable that the pair of support members be rotatable around the first central axis so as to assist the pair of housing shafts of the cleaning unit from being detached from the pair of shaft supports. ..

According to this configuration, when the cleaning unit is integrally detached from the apparatus main body together with the transport unit, the pair of support members become rotatable around the first central axis, so that the pair of housing shafts of the cleaning unit Can be easily detached from the pair of shaft branches. As a result, the cleaning unit can be easily removed from the transport unit.

In the above configuration, the transport units are arranged so as to face each other in the axial direction, and the pair of unit frames supporting the transport portion and the pair of unit frames are connected to each other along the axial direction. The lower connection frame that supports the cleaning unit arranged at the attachment / detachment position from below and the pair of unit frames above the lower connection frame are connected to each other along the axial direction, and at the attachment / detachment position. It has an upper connecting frame that defines the unit accommodating portion between the lower connecting frame and the lower connecting frame so as to cover at least a part of the arranged cleaning unit, and the rotation driving unit is said to have the same. The pair of support members are rotated around the first central axis so that the cleaning unit comes out of the unit accommodating portion in a horizontal direction orthogonal to the axial direction and reaches the cleaning position above the upper connection frame. It is desirable to move it.

According to this configuration, the rigidity of the transport unit can be maintained by connecting the pair of unit frames to the upper connection frame and the lower connection frame around the unit accommodating portion provided in the transport unit. Further, although the upper part of the cleaning unit arranged at the attachment / detachment position is covered with the upper connection frame, the cleaning unit comes out from the unit housing portion in the horizontal direction orthogonal to the axial direction and is above the upper connection frame. You can reach the cleaning position.

In the above configuration, an upper resist roller that conveys the sheet toward the image forming portion at the image forming timing in the image forming portion is further provided, and the conveying roller is arranged below the upper resist roller. A nip portion through which the sheet passes is formed between the upper resist roller and a lower resist roller that conveys the sheet toward the image forming portion in accordance with the image forming timing, and the cleaning device comprises the cleaning device. It is desirable to clean the surface of the lower resist roller.

According to this configuration, the cleaning device can stably feed the sheet to the image forming portion by cleaning the surface of the lower resist roller.

According to the present invention, it is possible to provide a cleaning device capable of contacting the surface of a transport roller for transporting a sheet without applying an excessive load and cleaning the surface, and an image forming apparatus provided with the cleaning device. ..

It is a schematic cross-sectional view which shows the internal structure of the image forming apparatus which concerns on one Embodiment of this invention. It is sectional drawing of the periphery of the resist roller pair and cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention, and is the sectional view of the state which the cleaning unit is arranged at the cleaning position. It is a perspective view of the cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention. It is a perspective view of the cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention. It is a perspective view of the cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention. It is sectional drawing of the cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention. It is a front view which showed omitting some members in the cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention. It is a perspective view which shows the internal structure of the cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention. It is a perspective view of the cleaning unit and the web feeding mechanism of the image forming apparatus which concerns on one Embodiment of this invention. It is an enlarged perspective view of a part of the cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention. It is an enlarged perspective view of a part of the cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention. It is a perspective view which shows the appearance that the transport unit frame was detached from the main body frame which constitutes the apparatus main body of the image forming apparatus which concerns on one Embodiment of this invention. It is a perspective view which shows the appearance that the transport unit frame is attached to the main body frame which comprises the apparatus main body of the image forming apparatus which concerns on one Embodiment of this invention. It is a perspective view of the transport unit frame of the image forming apparatus which concerns on one Embodiment of this invention. It is a perspective view of the transport unit frame of the image forming apparatus which concerns on one Embodiment of this invention. It is a perspective view of the cleaning unit rotating part of the transport unit frame which concerns on one Embodiment of this invention. It is an enlarged perspective view of a part of the cleaning unit rotating part of the transport unit frame which concerns on one Embodiment of this invention. It is an enlarged perspective view of a part of the cleaning unit rotating part of the transport unit frame which concerns on one Embodiment of this invention. It is sectional drawing which shows the appearance that the cleaning unit is attached to the transport unit frame which concerns on one Embodiment of this invention. It is sectional drawing which shows the appearance that the cleaning unit was attached to the transport unit frame which concerns on one Embodiment of this invention. It is an enlarged perspective view which shows the appearance that the cleaning unit was attached to the transport unit frame which concerns on one Embodiment of this invention. It is an enlarged perspective view which shows the appearance that the cleaning unit was attached to the transport unit frame which concerns on one Embodiment of this invention. It is a perspective view which shows the appearance that the cleaning unit was attached to the transport unit frame which concerns on one Embodiment of this invention. It is sectional drawing of the periphery of the resist roller pair and the cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention, and is the sectional view of the state which the cleaning unit is arranged in the attachment / detachment position. It is sectional drawing of the periphery of the resist roller pair and cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention, and is the sectional view of the state which the cleaning unit was slightly pushed up from the attachment and detachment position. It is sectional drawing of the periphery of the resist roller pair and the cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention, and is the sectional view of the state which the cleaning unit is arranged at the separated position. FIG. 5 is a cross-sectional perspective view of a resist roller pair and a cleaning unit of an image forming apparatus according to an embodiment of the present invention, in a state where the cleaning unit is arranged at a detachable position. FIG. 5 is a cross-sectional perspective view of a pair of resist rollers and a cleaning unit of an image forming apparatus according to an embodiment of the present invention, in a state where the cleaning unit is arranged at a cleaning position. FIG. 5 is a cross-sectional perspective view of a resist roller pair and a cleaning unit of an image forming apparatus according to an embodiment of the present invention, in a state where the cleaning unit is arranged at a detachable position. FIG. 5 is a cross-sectional perspective view of a pair of resist rollers and a cleaning unit of an image forming apparatus according to an embodiment of the present invention, in a state where the cleaning unit is arranged at a cleaning position. It is sectional drawing of the resist roller pair and cleaning unit of the image forming apparatus which concerns on one Embodiment of this invention, and is the sectional view of the state which the cleaning unit is arranged at the cleaning position. It is a graph (A), (B) and (C) which shows the nip load distribution of a resist roller pair. FIG. 5 is a cross-sectional perspective view of another resist roller pair and cleaning unit compared to one embodiment of the present invention.

Hereinafter, the cleaning device and the image forming device according to the embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic cross-sectional view showing the internal structure of the image forming apparatus 1 according to the embodiment of the present invention. The image forming apparatus 1 shown in FIG. 1 is an inkjet recording apparatus that ejects ink droplets to form (record) an image on the sheet S. The image forming apparatus 1 includes an apparatus main body 10, a paper feeding unit 20, a resist roller unit 30, a belt transport unit 40, an image forming unit 50, and a curl correction unit 60.

The device main body 10 is a box-shaped housing that houses various devices for forming an image on the sheet S. The apparatus main body 10 is formed with a first transport passage 11, a second transport passage 12, and a third transport passage 13 that serve as transport passages for the sheet S.

The paper feeding unit 20 feeds the sheet S to the first transport path 11. The paper feed unit 20 includes a paper feed cassette 21 and a paper feed roller 22. The paper feed cassette 21 is removable from the device main body 10 and houses the sheet S inside. The paper feed roller 22 is arranged on the right side of the upper end portion of the paper feed cassette 21. The paper feed roller 22 transports the sheet S housed in the paper feed cassette 21 to the downstream side of the first transport path 11.

The sheet S fed into the first transport path 11 reaches the resist roller portion 30 arranged at the downstream end of the first transport path 11 by the first transport roller pair 111 provided in the first transport path 11. Be transported. Further, a paper feed tray 24 is arranged on the right side surface of the apparatus main body 10, and a sheet S can be placed on the upper surface portion of the paper feed tray 24. The sheet S placed on the paper feed tray 24 is sent out toward the resist roller unit 30 by the paper feed roller 23.

The resist roller unit 30 is a device that conveys the sheet S carried in through the first transfer path 11 or the paper feed roller 23 toward the transfer belt 41 in the belt transfer unit 40 in the sheet transfer direction A1. The resist roller unit 30 and the belt transport unit 40 transport the sheet S at different positions from each other. Details of the resist roller unit 30 will be described later.

The sheet S conveyed by the resist roller unit 30 is conveyed in the sheet transfer direction A2 by the belt transfer unit 40. The sheet transport directions A1 and A2 are in the left direction in FIG.

The belt transport unit 40 is arranged below the image forming unit 50. The belt transport unit 40 transports the sheet S conveyed by the resist roller unit 30 in the sheet transfer direction A2 toward the curl correction unit 60 so that the sheet S passes below the image forming unit 50. The belt transport unit 40 includes a transport belt 41 (conveyance unit), a first support roller 421, a second support roller 422, a third support roller 423, a pair of fourth support rollers 424, and a suction unit 43. Has.

The transport belt 41 is an endless belt having a predetermined width in the front-rear direction and extending in the left-right direction. The transport belt 41 is arranged so as to face the image forming portion 50, and transports the sheet S in the sheet transport direction A2 on the outer peripheral surface 411. An image forming position at which image formation is formed on the sheet S is set by the image forming portion 50 on the orbital movement path of the transport belt 41.

The transport belt 41 is stretched on a first support roller 421, a second support roller 422, a third support roller 423, and a pair of fourth support rollers 424. Inside the stretched transport belt 41, a suction portion 43 is arranged so as to face the inner peripheral surface 412 of the transport belt 41. The first support roller 421 is rotationally driven by a drive motor (not shown) to orbit the transport belt 41 in a predetermined circumferential direction. Further, the transport belt 41 has a plurality of suction holes penetrating in the thickness direction from the outer peripheral surface 411 to the inner peripheral surface 412.

The suction unit 43 is arranged so as to face the image forming unit 50 via the transport belt 41. The suction unit 43 causes the sheet S to be brought into close contact with the outer peripheral surface 411 of the transfer belt 41 by generating a negative pressure between the sheet S held on the outer peripheral surface 411 of the transfer belt 41 and the transfer belt 41. The suction unit 43 includes a belt guide member 431, a suction housing 432, a suction device 433, and an exhaust duct 434.

The belt guide member 431 guides the orbital movement of the transport belt 41 linked to the rotation of the first support roller 421 between the first support roller 421 and the second support roller 422.

The suction portion 43 generates a suction force by sucking air from the space above the transport belt 41 through the groove portion and the through hole formed in the belt guide member 431 and the suction hole of the transport belt 41. Due to this suction force, an air flow (suction wind) toward the suction portion 43 is generated in the space above the transport belt 41. When the sheet S is conveyed onto the transfer belt 41 by the resist roller portion 30 and covers a part of the outer peripheral surface 411 of the transfer belt 41, a suction force (negative pressure) acts on the sheet S, and the sheet S is transferred to the transfer belt 41. It is in close contact with the outer peripheral surface 411 of the.

The suction housing 432 is a box-shaped housing having an opening on the upper side, and is arranged below the transport belt 41 so that the opening on the upper side is covered by the belt guide member 431. The suction housing 432 defines the suction space 432A in cooperation with the belt guide member 431.

An opening 432B is formed in the bottom wall portion of the suction housing 432, and a suction device 433 is arranged corresponding to the opening 432B. An exhaust duct 434 is connected to the suction device 433. The exhaust duct 434 is connected to an exhaust port (not shown) provided in the apparatus main body 10.

An image forming unit 50 is arranged on the upper side of the belt transport unit 40. The image forming unit 50 performs an image forming process on the sheet S which is conveyed in the sheet conveying direction A2 while being held on the outer peripheral surface 411 of the conveying belt 41 to form an image. In the present embodiment, the image forming method of the image forming unit 50 is an inkjet method, and ink droplets are ejected to form an image on the sheet S.

The image forming unit 50 includes a line head 51 (51Bk, 51C, 51M, 51Y). The line head 51Bk ejects black ink droplets, the line head 51C ejects cyan ink droplets, the line head 51M ejects magenta ink droplets, and the line head 51Y ejects yellow ink droplets. To do. The line heads 51Bk, 51C, 51M, and 51Y are arranged side by side from the upstream side to the downstream side in the sheet transport direction A1.

The line head 51 ejects ink droplets onto the sheet S transported in the sheet transport direction A2 while being held on the outer peripheral surface 411 of the transport belt 41 to form an image on the sheet S. As a result, an image is formed on the sheet S.

The sheet S on which the image is formed is conveyed by the conveying belt 41, guided by the sheet discharging guide section 44, and discharged (delivered) toward the curl correction section 60. The curl correction unit 60 is arranged on the downstream side of the sheet transport direction A2 of the transport belt 41 with the sheet discharge guide portion 44 interposed therebetween. The curl correction unit 60 corrects the curl of the sheet S while transporting the sheet S on which the image is formed to the downstream side.

The sheet S whose curl has been corrected by the curl correction unit 60 is sent to the second transport path 12. The second transport path 12 extends along the left side surface of the apparatus main body 10. The sheet S delivered to the second transport path 12 is transported toward the paper ejection port 12A formed on the left side of the apparatus main body 10 by the second transport roller pair 121 provided in the second transport path 12. It is discharged onto the paper ejection unit 14 from the paper ejection port 12A.

On the other hand, when double-sided printing is performed on the sheet S, the sheet S for which the image forming process of the first surface (front surface) is completed is sent out from the second transport path 12 to the sheet reversing portion 15. The sheet reversing portion 15 is a transport path branched in the middle of the second transport path 12, and is a portion where the sheet S is reversed (switched back). The sheet S whose front and back sides are inverted by the sheet inversion unit 15 is sent to the third transport path 13. The sheet S sent out to the third transport path 13 is back-fed by the third transport roller pair 131 provided in the third transport path 13, and is conveyed again through the resist roller portion 30 in a state where the front and back sides are reversed. It is supplied on the outer peripheral surface 411 of the belt 41. The sheet S supplied on the outer peripheral surface 411 of the transport belt 41 in such a state that the front and back sides are reversed is conveyed by the image forming portion 50 while being conveyed by the transfer belt 41, and the second surface opposite to the first surface. Image formation processing is applied to (back surface). The sheet S for which double-sided printing has been completed passes through the second transport path 12 and is discharged from the paper ejection port 12A onto the paper ejection unit 14.

FIG. 2 is a cross-sectional view of the periphery of the resist roller pair and the cleaning unit 70 of the image forming apparatus 1 according to the present embodiment, and is a cross-sectional view of a state in which the cleaning unit 70 is arranged at the cleaning position.

The resist roller portion 30 described above includes a resist housing 30H and a resist roller pair including a resist upper roller 31 (upper resist roller) and a resist lower roller 32 (conveyor roller, lower resist roller). The resist housing 30H is mounted on the apparatus main body 10 and rotatably supports the resist upper roller 31 and the resist lower roller 32. The sheet S is carried into the resist housing 30H into the nip portion of the resist roller pair as shown by the arrow in FIG. The resist roller unit 30 has a roller drive unit (not shown) that rotationally drives the resist upper roller 31 and the resist lower roller 32.

The resist upper roller 31 is a roller arranged on the upper side of the resist roller pair. The resist roller 31 is made of a metal roller.

The resist lower roller 32 is a roller arranged on the lower side of the resist roller pair. The under-resist roller 32 is made of a rubber roller, and a PFA (tetrafluoroethylene / perfluoroalkoxy alkane copolymer resin) tube is wound (fitted) around the outer peripheral surface thereof.

As shown in FIG. 2, the straight line L connecting the center of the upper resist roller 31 and the center of the lower resist roller 32 is inclined at an acute angle (for example, 10 degrees) with respect to the vertical direction. In other words, the lower resist roller 32 is located at a position shifted upstream of the resist upper roller 31 in the transport direction of the sheet S.

Further, the image forming apparatus 1 includes a cleaning apparatus 7. The cleaning device 7 is capable of cleaning the surface of the roller 32 under the resist. The cleaning device 7 has a cleaning unit 70 and a moving mechanism 75 (see FIG. 14). The moving mechanism 75 has a function of moving the cleaning unit 70 between the cleaning position (FIG. 2), the attachment / detachment position (FIG. 24), and the separation position (FIG. 26).

3 to 5 are perspective views of the cleaning unit 70 of the image forming apparatus 1 according to the present embodiment. FIG. 6 is a cross-sectional view of the cleaning unit 70 at the cross-sectional position I-I of FIG. FIG. 7 is a front view showing the cleaning unit 70 with some members omitted. FIG. 8 is a perspective view showing the internal structure (cleaning unit 70A) of the cleaning unit 70.

The cleaning unit 70 has a cleaning unit 70A and a cleaning housing 70H. The cleaning unit 70A has a shape extending along the axial direction of the resist lower roller 32 and comes into contact with the surface of the resist lower roller 32 from below to clean the surface.

The cleaning housing 70H supports the cleaning portion 70A. The cleaning housing 70H includes a front wall 701 and a rear wall 702 (a pair of wall portions), a connection wall 703, a pair of unit fulcrum pins 70P (housing shaft portion), a seat member 704, and a pair of guide rollers 705 (guides). Roller, guide member) and. The front wall 701, the rear wall 702, and the connecting wall 703 of the cleaning housing 70H are made of a metal material (magnetic material).

The front wall 701 and the rear wall 702 are arranged so as to face each other in the front-rear direction (axial direction of the roller 32 under the resist) and support the cleaning portion 70A. The connecting wall 703 connects the front wall 701 and the rear wall 702 along the front-rear direction. The connecting wall 703 has a side wall 703A and a bottom wall 703B (FIGS. 5 and 6). A pair of front and rear ribs 703T are provided so as to project from the bottom wall 703B (see FIGS. 19 and 20).

The pair of unit fulcrum pins 70P project from the outer surfaces of the front wall 701 and the rear wall 702 (a pair of wall portions) in the front-rear direction, respectively. The unit fulcrum pin 70P is arranged in the lower left portion of the front wall 701 and the rear wall 702. Each unit fulcrum pin 70P has a two-stage cylindrical shape whose outer diameter decreases toward the tip.

The sheet member 704 is fixed to the bottom wall 703B so as to define the left side surface of the cleaning unit 70 (FIG. 6). The sheet member 704 prevents collected materials such as paper dust collected by the cleaning unit 70 from scattering toward the belt transport unit 40 (FIG. 1).

The pair of guide rollers 705 are supported by the front wall 701 and the rear wall 702 above the unit fulcrum pin 70P, respectively, and include an outer peripheral surface that can rotate around a central axis (second central axis) parallel to the front-rear direction. It is a columnar member. The guide roller 705 is arranged (protruding in the axial direction) in the upper right portion of each outer surface of the front wall 701 and the rear wall 702. The pair of guide rollers 705 have a function of guiding the cleaning unit 70 when the cleaning unit 70 moves to the above-mentioned attachment / detachment position, separation position, and cleaning position.

The cleaning unit 70A includes a web W, a web driven roller 71 (feeding roller) rotatably supported by the front wall 701 and the rear wall 702, a pressing roller 72, and a web driving roller 73 (winding roller), respectively. , (FIGS. 6 to 8). The web W is composed of a band-shaped member having an abutting surface capable of abutting on the surface of the roller 32 under resist, and is made of a cloth material such as a non-woven fabric as an example. In the present embodiment, as shown in FIGS. 6 and 8, a web roll WR in which the web W is previously wound in a roll shape is fitted onto the web driven roller 71. Then, the tip of the web W is hung on the outer peripheral surface of the pressing roller 72 and then fixed to the outer peripheral surface of the web driving roller 73. The pressing roller 72 abuts on the back surface of the web W and presses the front surface of the web W against the roller 32 under the resist. When the cleaning unit 70 is arranged at the above-mentioned cleaning position (FIG. 2), the pressing roller 72 comes into contact with the resist lower roller 32 with the web W in between. The web driven roller 71 feeds out the web W so that the portion of the web W that comes into contact with the under-resist roller 32 changes, and the web driving roller 73 winds up the web W. As shown in FIG. 5, the state of the web roll WR held by the web driven roller 71 can be visually recognized from the outside of the cleaning unit 70 through the opening formed between the side wall 703A and the bottom wall 703B. it can. Therefore, it is possible to prevent the cleaning unit 70, which has been detached from the device main body 10 during use and has a small amount of web W that can be fed out, accidentally attached to the device main body 10.

Further, the cleaning unit 70 has a unit input gear 711 (FIG. 4), an interlocking gear 711T, a transmission gear 712, and a drive roller gear 713 (FIG. 6).

The unit input gear 711 is rotatably supported at the lower end and the right end of the front wall 701. The input gear shaft 711S of the unit input gear 711 penetrates the front wall 701 and extends to the inside (back side) of the front wall 701. The interlocking gear 711T is fixed to the input gear shaft 711S and rotates integrally with the unit input gear 711.

The transmission gear 712 is rotatably supported inside the front wall 701 and is engaged with the interlocking gear 711T and the drive roller gear 713, respectively. The drive roller gear 713 is a gear fixed to one end of the web drive roller 73.

FIG. 9 is a perspective view of the cleaning unit 70 and the web feeding mechanism 81 of the image forming apparatus 1 according to the present embodiment. 10 and 11 are enlarged perspective views of a part of the cleaning unit 70.

The cleaning device 7 further includes a web feeding mechanism 81 (web driving mechanism) and a control unit 90. The web feeding mechanism 81 is attached to the apparatus main body 10 of the image forming apparatus 1. The web sending mechanism 81 has a function of sending out the web W of the cleaning unit 70. The web feeding mechanism 81 is connected to the cleaning unit 70 by arranging the cleaning unit 70 at the cleaning position. The web feeding mechanism 81 includes a solenoid 811, a rotating arm 812, a third detection sensor 813, a transmission gear 814, and a transmission gear 815.

The solenoid 811 receives a command signal from the control unit 90 to generate a driving force for moving the web W. The solenoid 811 includes a haunting shaft 811S. The haunting shaft 811S haunts the main body of the solenoid 811. The solenoid 811 is supported by a sheet metal drive frame (not shown) arranged in the apparatus main body 10.

The rotating arm 812 is rotatably supported by a shaft 812S (FIG. 9) provided in the drive frame in the apparatus main body 10. The shaft 812S is supported by the drive frame so as to be rotatable around a rotation center axis extending in the front-rear direction. The rotating arm 812 has a first arm portion 812A and a second arm portion 812B. The first arm portion 812A extends to the right from the rotation center axis of the rotation arm 812. The tip of the first arm portion 812A is connected to the haunting shaft 811S. The second arm portion 812B extends downward from the rotation center axis of the rotation arm 812 on the side opposite to the first arm portion 812A. A detection piece 812C is arranged at the tip end portion (lower end portion) of the second arm portion 812B. Further, the rear end portion of the shaft 812S is provided with a gear portion 812T capable of rotating integrally with the shaft 812S. Further, the web feeding mechanism 81 has a first one-way clutch and a second one-way clutch (both not shown). The first one-way clutch is fixed inside the rotating arm 812 and fitted to the shaft 812S. Further, the second one-way clutch is fixed to the drive frame so as to be adjacent to the first one-way clutch and is fitted to the shaft 812S.

The third detection sensor 813 is fixed to the left end of the main body of the solenoid 811. The third detection sensor 813 is a PI sensor that detects the movement (rotation) of the detection piece 812C. The control unit 90 can detect the amount of feeding of the web roll WR according to the number of detections of the detection piece 812C output from the third detection sensor 813. Further, when the number of detections reaches a preset threshold number, the control unit 90 displays a replacement message of the cleaning unit 70 on a display unit (not shown) of the image forming apparatus 1.

The transmission gear 814 is rotatably supported by the apparatus main body 10 and is engaged with the gear portion 812T. The transmission gear 814 is composed of a two-stage gear. Similarly, the transmission gear 815 is rotatably supported by the apparatus main body 10 and engages with the rear gear portion of the two-stage gear of the transmission gear 814 and also engages with the unit input gear 711 described above. doing.

FIG. 9 shows a state in which the haunting shaft 811S is immersed (contracted) with respect to the main body of the solenoid 811. When the control unit 90 inputs a command signal to the solenoid 811 from the state of FIG. 9, the infestation shaft 811S protrudes (extends) from the main body of the solenoid 811, so that the rotating arm 812 rotates around the shaft 812S and is counterclockwise in FIG. Rotate clockwise. At this time, the rotating arm 812 rotates relative to the shaft 812S due to the action of the first one-way clutch described above, so that the shaft 812S does not rotate. On the other hand, when sending out a predetermined amount of the web W, the control unit 90 inputs a command signal to the solenoid 811 to contract the haunting shaft 811S with respect to the main body of the solenoid 811. As a result, the rotating arm 812 rotates clockwise around the shaft 812S in FIG. 9. At this time, the shaft 812S rotates integrally with the rotating arm 812 by a predetermined angle by the action of the first one-way clutch described above. As a result, the rotational driving force is input from the gear portion 812T fixed to the shaft 81S to the unit input gear 711 via the transmission gear 814 and the transmission gear 815. Then, the rotational driving force is further transmitted to the unit input gear 711, the interlocking gear 711T, the transmission gear 712, and the drive roller gear 713 of the cleaning unit 70, the web drive roller 73 rotates by a preset rotation angle, and the web W Moves so that it is wound up by the web drive roller 73. As a result, the portion of the contact surface of the web W that faces the roller 32 under the resist changes. Each time the rotation arm 812 rotates for one reciprocation, the third detection sensor 813 detects the detection piece 812C, so that the unit input gear 711 rotates and the web W moves.

When the web W moves, the control unit 90 inputs a command signal to the solenoid 811 to cause the haunting shaft 811S to project again with respect to the main body of the solenoid 811. At this time, the shaft 812S is prevented from rotating in the reverse direction by the action of the second one-way clutch described above. Further, as shown in FIG. 11, the one-way clutch 73T provided on the drive roller shaft 73S of the web drive roller 73 functions, and the web drive roller 73 is prevented from rotating in the reverse direction. Therefore, each time the control unit 90 performs the infestation operation of the infestation shaft 811S, the web W moves to the web drive roller 73 side by a predetermined amount. As described above, in the present embodiment, it is possible to send out the web W from the web roll WR by utilizing the slight infestation stroke of the infestation shaft 811S of the solenoid 811. In another embodiment, the web feeding mechanism 81 may rotationally drive the web driven roller 71 in addition to the web driving roller 73.

In addition, referring to FIG. 9, the pressing roller shaft 72S of the pressing roller 72 is provided with a torque limiter 72T. The web W (pressing roller 72) of the cleaning device 7 is in contact with the lower resist roller 32, and the sheet S is clogged in the image forming apparatus 1 with the sheet S sandwiched between the upper resist roller 31 and the lower resist roller 32. May occur. In this case, the user opens the predetermined cover of the apparatus main body 10 of the image forming apparatus 1 and pulls out the sheet S in the direction opposite to the arrow in FIG. 2, thereby causing the resist upper roller 31 and the resist lower roller 32. Attempts to remove the sheet S stuck between and. At this time, when the force for pulling out the sheet S is transmitted from the resist lower roller 32 to the pressing roller 72, the web W is excessively sent out from the pressing roller 72 to the web driving roller 73 side. In the present embodiment, since the pressing roller shaft 72S is provided with the torque limiter 72T, when a sudden rotational force is applied to the pressing roller 72, the rotation of the pressing roller 72 is locked and the web W is unwound. Be prevented.

Further, referring to FIG. 10, in the present embodiment, the brake spring 71T is interposed between the E-ring 71R1 and the flange 71R2 in the driven roller shaft 71S of the web driven roller 71 in a compressed and deformed state. .. In FIG. 10, the front wall 701 of FIG. 9 is not shown. The flange 71R2 is a ring-shaped flange fixed to the pressing roller shaft 72S of the pressing roller 72. The rear end of the brake spring 71T is in contact with the flange 71R2. Further, the front end portion of the brake spring 71T is in contact with the back surface of the front wall 701. As a result, the compressive force of the brake spring 71T is applied to the pressing roller 72 via the flange 71R2, and the pressing roller 72 is prevented from rotating unnecessarily. As a result, even though the control unit 90 does not control the solenoid 811, the web W is prevented from being fed out from the pressing roller 72.

The moving mechanism 75 (FIG. 2) has a cleaning unit 70 at a cleaning position (FIG. 2), an attachment / detachment position below the cleaning position (FIG. 24), and a separation position between the cleaning position and the attachment / detachment position (FIG. 26). ) And can be moved. The moving mechanism 75 allows the cleaning unit 70A to come into contact with the resist lower roller 32 at the cleaning position, and the cleaning unit 70A is arranged downward with respect to the resist lower roller 32 at the attachment / detachment position and is a cleaning unit. Allows 70 to be attached to and detached from the device body 10. Further, at the separated position, the cleaning unit 70A is arranged so as to be separated downward from the resist lower roller 32, and the connection between the cleaning unit 70 and the above-mentioned web feeding mechanism 81 (web driving mechanism) is released.

FIG. 12 is a perspective view showing a state in which the transport unit frame 40H is detached from the main body frame 100 constituting the device main body 10 of the image forming apparatus 1 according to the present embodiment. FIG. 13 is a perspective view showing a state in which the transport unit frame 40H is attached to the main body frame 100. 14 and 15 are perspective views of the transport unit frame 40H.

The belt transport unit 40 (conveyor unit) shown in FIG. 1 further includes a transport unit frame 40H. The transport unit frame 40H integrally includes a transport belt 41, a first support roller 421, a second support roller 422, a third support roller 423, a pair of fourth support rollers 424, and a suction unit 43. I support it. The transport unit frame 40H can be mounted on the main body frame 100 of the apparatus main body 10 along the first direction (rear direction) parallel to the front-rear direction (axial direction of the roller 32 under the resist), and the first from the main body frame 100. It is said that it can be detached along the second direction (forward direction) opposite to the one direction.

With reference to FIGS. 14 and 15, the transport unit frame 40H includes a front frame 401, a rear frame 402, a left frame 403, a first right frame 404A (upper connection frame), and a second right frame 404B (lower). It has a side connection frame), a pair of front and rear magnets 404C (magnetic members), and a pair of left and right rail portions 40R.

The front frame 401 is a frame arranged on the front surface of the transport unit frame 40H. As shown in FIGS. 14 and 15, the front cover 401A is attached to the front frame 401. The front cover 401A constitutes a part of the front surface portion of the apparatus main body 10. The rear frame 402 is a frame arranged on the rear surface portion of the transport unit frame 40H, and is arranged so as to face the front frame 401 in the front-rear direction. The left frame 403 is arranged at the left end of the transport unit frame 40H, and connects the front frame 401 and the rear frame 402 along the front-rear direction. The first right frame 404A and the second right frame 404B are arranged at the right end of the transport unit frame 40H, and connect the front frame 401 and the rear frame 402 along the front-rear direction. The first right frame 404A is arranged along the upper surface of the transport unit frame 40H, and the second right frame 404B is arranged below the first right frame 404A. Both ends of the first right frame 404A and the second right frame 404B in the front-rear direction are connected to each other along the vertical direction by a pair of side plates (not shown) arranged inside the front frame 401 and the rear frame 402. ing. As a result, the first right frame 404A, the second right frame 404B, and the pair of side plates described above form a rectangular frame structure. The pair of left and right rail portions 40R are rail portions for the transport unit frame 40H to slide and move in the front-rear direction with respect to the main body frame 100. Although only the right rail portion 40R appears in FIGS. 14 and 15, a similar rail portion 40R is also arranged at the left end portion of the transport unit frame 40H. The pair of magnets 404C are magnets arranged at intervals in the front-rear direction on the upper surface of the second right frame 404B. The pair of magnets 404C has a function of holding the cleaning unit 70.

As shown in FIGS. 14 and 15, the transport unit mounting portion 40A is formed on the left side of the first right frame 404A and the second right frame 404B in the transport unit frame 40H. The transport belt 41, the first support roller 421, the second support roller 422, the third support roller 423, the pair of fourth support rollers 424, the suction section 43, and the like are arranged in the transport unit mounting portion 40A. On the other hand, a cleaning unit mounting portion 40B (unit accommodating portion) is arranged in the space between the first right frame 404A and the second right frame 404B. The cleaning unit mounting unit 40B allows the above-mentioned cleaning unit 70 arranged at the attachment / detachment position to be mounted, and accommodates the cleaning unit 70. The cleaning unit mounting portion 40B constitutes a part of the moving mechanism 75.

Further, the transport unit frame 40H has a cleaning unit rotating portion 45 and a rotating input gear 40G. FIG. 16 is a perspective view of the cleaning unit rotating portion 45 of the transport unit frame 40H according to the present embodiment. 17 and 18 are enlarged perspective views of a part of the cleaning unit rotating portion 45.

As shown in FIGS. 14 and 15, the cleaning unit rotating portion 45 is supported by the pair of side plates directly below the first right frame 404A. With reference to FIG. 16, the cleaning unit rotating portion 45 includes a rotating shaft 451, a pair of front and rear bearings 451S, a rotating gear 452, a pair of front and rear lever support portions 453 (fixing members), and a pair of front and rear bearings. It has a rotary lever 454 (support member) and a pair of front and rear coil springs 455 (spring member).

The rotating shaft 451 is rotatably supported by the pair of side plates via a pair of front and rear bearings 451S. The rotating shaft 451 extends along the front-rear direction (axial direction of the roller 32 under the resist) and forms a central axis (first central axis) in the rotation of the pair of rotating levers 454. The rotary gear 452 is a gear fixed to the rear end portion of the rotary shaft 451 and can be engaged with the rotary input gear 40G.

A pair of front and rear rotating levers 454 are arranged on the cleaning unit mounting portion 40B, and support the cleaning housing 70H so as to sandwich the cleaning housing 70H of the cleaning unit 70 from both sides in the front-rear direction (axial direction of the roller 32 under the resist). Is possible. With reference to FIGS. 17 and 18, each rotating lever 454 has a lever bottom portion 454A, a first lever side portion 454B, and a second lever side portion 454C. The lever bottom portion 454A includes a surface parallel to the axial direction of the rotating shaft 451 and extends in the radial direction of the rotating shaft 451. The first lever side portion 454B and the second lever side portion 454C are wall portions erected from the front and rear side edges of the lever bottom portion 454A, and are arranged so as to be orthogonal to the axial direction of the rotating shaft 451. .. The second lever side portion 454C has a substantially rectangular shape slightly larger than the outer diameter of the rotating shaft 451, and the first lever side portion 454B has a rotating shaft larger than the second lever side portion 454C. It extends radially from 451.

Holes through which the rotating shaft 451 is inserted are opened in the first lever side portion 454B and the second lever side portion 454C, respectively. As a result, the rotary lever 454 is rotatably supported by the rotary shaft 451.

Further, a pin receiving portion 454P (shaft support portion) and a notch portion 454Q are formed on the first lever side portion 454B. The pin receiving portion 454P has a shape in which the side edge of the first lever side portion 454B is cut out in an elongated hole shape. The pin receiving portion 454P accepts the unit fulcrum pin 70P (FIGS. 3 and 4) of the cleaning unit 70 along the direction orthogonal to the front-rear direction (the axial direction of the roller 32 under the resist) and makes the unit fulcrum pin 70P rotatable. Has a supporting function. The cutout portion 454Q has a shape in which the side edge of the first lever side portion 454B is cut out in a substantially rectangular shape between the pin receiving portion 454P and the rotating shaft 451.

The pair of front and rear lever support portions 453 are fixed to the rotation shaft 451 by a screw V so that the pair of rotation levers 454 can be held respectively. The lever support portion 453 has a support convex portion 453A arranged so as to extend in the front-rear direction in the notch portion 454Q. The tip of the support convex portion 453A has a shape bent so as to be orthogonal to the main body portion of the lever support portion 453.

With reference to FIGS. 17 and 18, the pair of front and rear coil springs 455 are arranged so as to be interposed between the lever support portion 453 and the rotation lever 454, respectively. Specifically, each coil spring 455 has a first spring end portion 455A and a second spring end portion 455B. The first spring end portion 455A is locked to the upper surface portion of the support convex portion 453A. Further, the second spring end portion 455B is locked to the lower surface portion of the lever bottom portion 454A of the rotating lever 454. As a result, the coil spring 455 can rotate the rotating lever 454 relative to the lever support portion 453 within a predetermined allowable angle range around the central axis (first central axis) of the rotating shaft 451. In addition, elastically deformable intervenes between the rotary lever 454 and the lever support portion 453. When no external force is applied to the lever support portion 453 and the rotary lever 454, the elastic force of the coil spring 455 causes the relative position of the lever support portion 453 and the rotary lever 454 in the circumferential direction (rotation direction). It is regulated. In other words, in FIGS. 17 and 18, when the position of the rotary lever 454 is fixed, the lever support portion 453 and the rotary shaft 451 elastically deform the coil spring 455 with respect to the rotary lever 454. It can rotate relative to the rotation lever 454.

Further, the cleaning device 7 has a rotation drive unit 75K. The rotation drive unit 75K constitutes a part of the movement mechanism 75. The rotation drive unit 75K has a pair of rotations so that the cleaning unit 70 moves between the cleaning position and the attachment / detachment position in a state where the pair of unit fulcrum pins 70P are pivotally supported by the pair of pin receiving portions 454P. The moving lever 454 is rotated around the central axis (first central axis) of the rotating shaft 451. The central axis is arranged above the pin receiving portion 454P in FIG. Further, in the rotation drive unit 75K, the pair of unit fulcrum pins 70P with respect to the pair of pin receiving portions 454P so that the cleaning unit 70 maintains the posture in which the cleaning unit 70A (web W) of the cleaning unit 70 faces upward. The pair of rotation levers 454 are rotated while allowing relative rotation.

The rotation drive unit 75K has a unit drive unit 80 (FIG. 2) (drive unit) in addition to the cleaning unit rotation unit 45 described above. The unit drive unit 80 generates a driving force that rotates the rotation shaft 451 of the cleaning unit rotation unit 45 around its central axis.

With reference to FIG. 2, the unit drive unit 80 includes a motor (not shown) including a drive motor output shaft 801, a pulse plate 802, a first detection sensor 803, a second detection sensor 804, and a unit drive output gear 805. (Fig. 24) and. The rotational drive of the motor is controlled by the control unit 90 described above.

The pulse plate 802 is fixed to the drive motor output shaft 801 and rotates integrally with the drive motor output shaft 801. The first detection sensor 803 detects the amount of rotation of the pulse plate 802. Specifically, the first detection sensor 803 has a light emitting unit that emits detection light and a light receiving unit that receives the detection light. The pulse plate 802 is formed with a plurality of slits opened at intervals along the rotation direction thereof. As the pulse plate 802 rotates, the detection light is shielded by the slit, and the light receiving unit outputs a signal corresponding to the waveform to the control unit 90, whereby the drive motor output shaft 801 (a pair of rotating levers 454). The amount of rotation is detected.

The second detection sensor 804 is composed of a known PI sensor and detects that the cleaning unit 70 is arranged at the cleaning position shown in FIG. In the present embodiment, the second detection sensor 804 detects the cleaning unit 70 when a part of the cleaning housing 70H of the cleaning unit 70 enters between the light emitting portion and the light receiving portion of the second detection sensor 804.

The unit drive output gear 805 transmits the rotational driving force generated by the motor of the unit drive unit 80 to the rotation input gear 40G of the cleaning unit rotation unit 45. In the present embodiment, when the transport unit frame 40H is mounted on the main body frame 100, the rotation input gear 40G and the unit drive output gear 805 are engaged with each other, and the rotation driving force can be transmitted.

FIG. 19 is a cross-sectional view showing how the cleaning unit 70 is mounted on the transport unit frame 40H according to the present embodiment, and FIG. 20 is a cross-sectional view showing how the cleaning unit 70 is mounted on the transport unit frame 40H. Is. 21 and 22 are enlarged perspective views showing a state in which the cleaning unit 70 is mounted on the transport unit frame 40H. FIG. 23 is a perspective view showing a state in which the cleaning unit 70 is mounted on the transport unit frame 40H. FIG. 24 is a cross-sectional view of the periphery of the resist roller pair of the image forming apparatus 1 and the cleaning unit 70, and is a cross-sectional view of the state where the cleaning unit 70 is arranged at the attachment / detachment position. FIG. It is the same cross-sectional view in the state of being pushed up slightly from the attachment / detachment position. FIG. 26 is a cross-sectional view of the periphery of the resist roller pair and the cleaning unit 70 of the image forming apparatus, and is a cross-sectional view of a state in which the cleaning unit 70 is arranged at a separated position. FIG. 27 is a cross-sectional perspective view showing a state in which the cleaning unit 70 is arranged at the attachment / detachment position. FIG. 28 is a cross-sectional perspective view showing a state in which the cleaning unit 70 is arranged at the cleaning position. FIG. 29 is a cross-sectional perspective view showing a state in which the cleaning unit 70 is arranged at the attachment / detachment position. FIG. 30 is a cross-sectional perspective view showing a state in which the cleaning unit 70 is arranged at the cleaning position. FIG. 31 is a cross-sectional view of a state in which the cleaning unit 70 is arranged at the cleaning position.

With reference to FIG. 24, the moving mechanism 75 further has a guide portion 100G. The guide portion 100G allows the pair of guide rollers 705 to come into contact with each other as the pair of rotation levers 454 rotate around the first central axis, and the cleaning unit 70 is placed between the cleaning position and the attachment / detachment position. I will guide you between. The guide portion 100G has a pair of front and rear first guide surfaces 101R and a pair of front and rear second guide surfaces 102R. The front and rear pair of first guide surfaces 101R are formed from the left side surfaces of the front and rear pair of guide frames 101 provided in the main body frame 100, respectively. The first guide surface 101R is inclined so as to guide the cleaning unit 70 (guide roller 705) to the right side as it advances upward. Similarly, the pair of front and rear guide surfaces 102R are each composed of a part of the pair of front and rear resist frames 102 (FIG. 27) provided in the main body frame 100. The second guide surface 102R is slightly inclined so as to guide the cleaning unit 70 (guide roller 705) to the left side as it advances upward.

Further, the moving mechanism 75 has a pair of front and rear positioning portions 102S. The positioning unit 102S regulates the relative position between the pressing roller 72 of the cleaning unit 70A and the roller under resist 32 by receiving the guide roller 705 of the cleaning unit at the cleaning position and contacting the guide roller 705, and the web of the cleaning unit 70A. The cleaning unit 70 is positioned so that W can clean the roller 32 under the resist. As shown in FIG. 24, the positioning portion 102S is connected to the second guide surface 102R and is composed of a concave portion having an arc shape (inner peripheral surface) along the outer peripheral surface of the guide roller 705. In FIG. 24, each member on the rear side of the pair of front and rear first guide surfaces 101R, second guide surface 102R, and positioning portion 102S appears.

As shown in FIG. 12, when the transport unit frame 40H is pulled forward from the main body frame 100 of the apparatus main body 10, the operator can mount the cleaning unit 70 on the cleaning unit mounting portion 40B of the transport unit frame 40H. At this time, as shown in FIG. 19, the pair of rotating levers 454 are arranged so as to extend downward from the rotating shaft 451 (first central axis), and the pin receiving portion 454P is on the right side (width direction) of the rotating lever 454. The side portion of (one end side) is left side (the other end side opposite to the one end side in the width direction) and has a shape notched diagonally downward. Therefore, the operator can insert and fit the pair of left and right unit fulcrum pins 70P of the cleaning unit 70 into the pin receiving portion 454P while grasping the side wall 703A and the bottom wall 703B (FIG. 6) of the cleaning unit 70. Yes (Fig. 20). At this time, the unit input gear 711 described above is arranged behind the unit fulcrum pin 70P on the front side of the cleaning unit 70 (FIG. 21). Further, the unit fulcrum pin 70P on the rear side of the cleaning unit 70 is fitted into the pin receiving portion 454P as shown in FIG.

When the pair of unit fulcrum pins 70P of the cleaning unit 70 are fitted into the pin receiving portion 454P of the pair of rotating levers 454 by an operator, the bottom wall 703B of the cleaning housing 70H is arranged so as to face the pair of magnets 404C. , The pair of ribs 703T abut on the upper surface of the second right frame 404B, respectively. As a result, the cleaning unit 70 is held by the second right frame 404B by the magnetic field generated by the pair of magnets 404C in addition to the pair of rotating levers 454. Therefore, even if the operator releases the cleaning unit 70, the cleaning unit 70 is prevented from falling off from the transport unit frame 40H.

As described above, when the cleaning unit 70 is mounted on the cleaning unit mounting portion 40B (detachable position) of the transport unit frame 40H, the operator inserts the transport unit frame 40H into the main body frame 100 (FIG. 23). As a result, the cleaning unit 70 is inserted into the main body frame 100, and the rotation input gear 40G of the transport unit frame 40H engages with the unit drive output gear 805 of the unit drive unit 80 in the main body frame 100. At this time, a pair of front and rear guide rollers 705 of the cleaning unit 70 are arranged to face the first guide surface 101R of the pair of front and rear guide portions 100G at a predetermined distance in the left-right direction.

As shown in FIG. 24, when the cleaning unit 70 arranged at the attachment / detachment position is viewed from a direction parallel to the axial direction of the resist lower roller 32, the center (P2) of the unit fulcrum pin 70P supported by the pin receiving portion 454P is , Is arranged below the central axis (P1) of the rotating shaft 451 and on the right side (one end side in the width direction). Further, the center of gravity (J) of the cleaning unit 70 is arranged on the right side of the unit fulcrum pin 70P. In the present embodiment, the shaft of the pressing roller 72 of the cleaning unit 70 is made of metal (as an example, a SUS material having a diameter of 10 mm), and the surface of the pressing roller 72 is an EPDM sponge roller. Therefore, as shown in FIG. 24, the cleaning unit. The center of gravity of the 70 is eccentric to the right side portion of the cleaning unit 70 so as to be located further to the right side of the center (P4) of the pressing roller 72. Further, the center (P3) of the magnet 404C in the left-right direction (width direction) is arranged on the right side (the tip side in the moving direction of the cleaning unit 70 in the left-right direction) with respect to the center (P2) of the unit fulcrum pin 70P.

From the state shown in FIG. 24, the control unit 90 controls the unit drive unit 80, and the rotation drive unit 75K rotates the pair of rotation levers 454 around the rotation shaft 451 (arrow D251 in FIG. 25). At this time, as the unit fulcrum pin 70P moves, the left end portion of the bottom wall 703B moves upward (arrow D252 in FIG. 25). As a result, the distance between the left end of the bottom wall 703B and the magnet 404C is increased, so that the influence of the magnetic binding force of the magnet 404C is reduced, and the bottom wall 703B of the cleaning unit 70 can be easily detached from the magnet 404C. it can. After that, when the cleaning unit 70 tilts to the right with respect to the unit fulcrum pin 70P due to the weight of the cleaning unit 70 (arrow D253 in FIG. 25), the pair of guide rollers 705 are placed on the first guide surface 101R of the pair of guide portions 100G. Each abuts. In FIG. 25, since the guide roller 705 is hidden behind the rear wall 702, the contact portion between the guide roller 705 and the first guide surface 101R cannot be seen, but in the actual state of FIG. 25. , The guide roller 705 is in contact with the first guide surface 101R.

After that, when the control unit 90 further rotates the pair of rotation levers 454, the cleaning unit 70 moves upward and to the right while the pair of guide rollers 705 are guided by the first guide surface 101R. At this time, the rotation locus of the rotation lever 454 and the movement locus of the cleaning unit 70 guided by the first guide surface 101R are different from each other. In the present embodiment, the pair of unit fulcrum pins 70P of the cleaning unit 70 are supported so as to be rotatable relative to the pin receiving portion 454P of the rotating lever 454. Therefore, as shown in FIGS. 25 and 26, the posture of the cleaning unit 70 can be changed with the upward movement, so that the cleaning unit 70 is smooth according to the rotation of the rotation lever 454. Can rise to.

In the state shown in FIG. 26, the pair of guide rollers 705 are delivered from the first guide surface 101R to the second guide surface 102R. Then, when the control unit 90 further rotates the rotation lever 454, the pair of guide rollers 705 abut and are fitted into the pair of positioning units 102S (FIG. 31). At this time, as shown in FIG. 2, the pressing roller 72 of the cleaning portion 70A of the cleaning unit 70 is lowered to the resist lower roller 32 along a straight line L connecting the center of the resist upper roller 31T and the center of the resist lower roller 32. Contact from. At this time, the rotary lever 454 extends obliquely downward from the rotary shaft 451 so as to intersect with the vertical direction at an acute angle (see FIG. 28). Therefore, the unit fulcrum pin 70P is prevented from being detached from the pin receiving portion 454P. In this way, when the cleaning unit 70 reaches the cleaning positions shown in FIGS. 2, 28, 30 and 31, respectively, the pressing roller 72 presses the web W against the resist lower roller 32, whereby the resist lower roller 32 It is possible to clean pigments and paper dust adhering to the surface of the paper. In the posture of the cleaning unit 70 at the cleaning position shown in FIG. 2, the center of gravity (pressing roller 72) of the cleaning unit 70 is arranged directly above the unit fulcrum pin 70P, so that the posture of the cleaning unit 70 at the cleaning position is stable. And be maintained. Further, by continuing to apply the exciting current to the motor of the unit drive unit 80, the control unit 90 can hold the cleaning unit 70 in the cleaning position without the rotation lever 454 rotating in the reverse direction. In another embodiment, a lock mechanism for locking the cleaning unit 70 to the cleaning position and an unlocking mechanism for releasing the lock and allowing the cleaning unit 70 to move from the cleaning position to the attachment / detachment position may be provided.

As described above, in the present embodiment, the cleaning device 7 has the cleaning unit 70 and the moving mechanism 75, and cleans the surface of the roller 32 under the resist. Since the moving mechanism 75 can move the cleaning unit 70 between at least the cleaning position and the attachment / detachment position, when the moving mechanism 75 arranges the cleaning unit 70 in the cleaning position, the positioning unit 102S registers with the cleaning unit 70A. By restricting the relative position with the lower roller 32, the cleaning unit 70A of the cleaning unit 70 can clean the resist lower roller 32, while the moving mechanism 75 arranges the cleaning unit 70 at a position attached / detached below the cleaning position. Then, the cleaning unit 70A is separated downward from the roller 32 under the resist, and the cleaning unit 70 can be attached to and detached from the apparatus main body 10. As a result, the cleaning unit 70 can be detached from the apparatus main body 10 without applying a large load to the roller 32 under the resist. Further, since the positioning portion 102S is arranged at a position different from that of the resist lower roller 32 at the cleaning position, when another positioning portion is provided at a portion where the pressing roller 72 of the cleaning portion 70A and the resist lower roller 32 come into direct contact with each other. In comparison with the above, it is suppressed that the pressing force of the cleaning unit 70A (pressing roller 72) is excessively applied to the roller 32 under the resist.

Further, in the present embodiment, the outer peripheral surface of the guide roller 705 is fitted into the positioning portion 102S formed of the concave portion, so that the relative position between the pressing roller 72 of the cleaning portion 70A and the resist lower roller 32 can be stably regulated. it can.

Further, the cleaning unit 70 can be moved between the attachment / detachment position and the cleaning position simply by rotating the pair of rotation levers 454 around the rotation shaft 451 (first central axis) by the rotation drive unit 75K. it can. At this time, the pair of unit fulcrum pins 70P rotate relative to the pair of pin receiving portions 454P, so that the cleaning unit 70 maintains a posture in which the pressing roller 72 (web W) of the cleaning portion 70A faces upward. it can. Therefore, at the same time that the cleaning unit 70 that has reached the cleaning position comes into contact with the positioning portion 102S, the pressing roller 72 of the cleaning portion 70A can come into contact with the resist lower roller 32 from below.

Further, in the present embodiment, since the cleaning housing 70H has a pair of guide rollers 705, the pair of guide rollers 705 and a pair of guide rollers 705 are rotated according to the rotation of the pair of rotation levers 454 by the rotation drive unit 75K. The guide unit 100G can stably guide the cleaning unit 70 between the attachment / detachment position and the cleaning position.

In addition, referring to FIG. 2, in the present embodiment, the resist lower roller 32 is arranged at a position below the resist upper roller 31 and shifted to the right side (upstream side in the transport direction of the sheet S) from the resist upper roller 31. Will be done. As a result, the sheet S can be stably conveyed toward the image forming position arranged at a position lower than the resist roller pair. On the other hand, the cleaning unit mounting portion 40B provided on the transport unit frame 40H is located below the resist roller pair and on the left side (upstream side in the sheet transport direction) of the resist roller pair. When moving the cleaning unit 70 from the attachment / detachment position arranged on the cleaning unit mounting portion 40B to the cleaning position directly under the resist lower roller 32, a straight line connecting the center of the resist upper roller 31 and the center of the resist lower roller 32. In order to bring the pressing roller 72 into contact with the resist lower roller 32 along L, a complicated moving mechanism is usually required. In particular, in order to move the cleaning unit 70 linearly, after moving the cleaning unit 70 linearly to an intermediate position to the right of the attachment / detachment position, the cleaning unit 70 is moved upward and to the left from the intermediate position. It is necessary to move it along the straight line L toward it. In this case, a plurality of linear movement paths intersecting each other are required.

On the other hand, in the present embodiment, the movement of the cleaning unit 70 between the attachment / detachment position and the cleaning position as described above is realized by the rotation of the pair of rotation levers 454 and the guide function by the guide portion 100G. In particular, the rotary lever 454 moves the cleaning unit 70 to the right and upward from the attachment / detachment position toward the cleaning position. On the other hand, when the pair of guide portions 100G guide the guide roller 705 of the cleaning unit 70 upward, the movement locus of the pressing roller 72 of the cleaning unit 70 is different from the rotation locus of the rotation lever 454. The pressing roller 72 is arranged so as to be reached by the under-resist roller 32 through a short locus. Then, in order to prevent the cleaning unit 70 from coming into contact with the roller 32 under the resist along the straight line L and preventing the cleaning unit 70 from hindering the rotation of the rotation lever 454, the cleaning unit 70 is rotating during the rotation of the rotation lever 454. Unit fulcrum pin 70P can rotate relative to the rotation lever 454. According to such a configuration, the cleaning unit 70 can be moved between the attachment / detachment position and the cleaning position in the limited space below the resist roller pair, and the pressing roller 72 is resisted along the straight line L. It can be brought into contact with and separated from the lower roller 32. Further, since the cleaning unit mounting portion 40B provided on the transfer unit frame 40H can be arranged on the left side (belt transfer unit 40 side) of the resist roller pair instead of directly under the resist roller pair, the transfer unit frame 40H Of these, the cleaning unit mounting portion 40B is provided in a limited space adjacent to the transport unit mounting portion 40A, and the transport unit frame 40H can be made compact.

Further, in the present embodiment, the rotary lever 454 has a pin receiving portion 454P for receiving the unit fulcrum pin 70P. Then, the rotation drive unit 75K moves the pair of rotation levers 454 around the rotation shaft 451 so that the unit fulcrum pin 70P moves to the right and upward from the state where the cleaning unit 70 is arranged at the attachment / detachment position. By rotating, the cleaning unit 70 is moved to the cleaning position. According to such a configuration, the pair of unit fulcrum pins 70P of the cleaning unit 70 can be easily taken in and out of the pin receiving portion 454P of the pair of rotating levers 454 along the direction orthogonal to the axial direction at the attachment / detachment position. it can. Further, in a state where the pair of unit fulcrum pins 70P are fitted into the pair of pin receiving portions 454P by the weight of the cleaning unit 70, the cleaning unit 70 can be stably moved to the cleaning position above the attachment / detachment position.

Further, in the present embodiment, when the rotation drive unit 75K rotates the pair of rotation levers 454 around the rotation shaft 451 at the attachment / detachment position, the cleaning unit 70 tilts by its own weight, and the pair of guide rollers 705 are paired. Each of the guide portions 100G is in contact with the guide portion 100G. Therefore, the cleaning unit 70 can be stably and smoothly moved from the attachment / detachment position to the cleaning position without the need for another drive mechanism for bringing the pair of guide rollers 705 into contact with the pair of guide portions 100G. it can.

Further, in the present embodiment, at least one magnet 404C is arranged in the second right frame 404B. Therefore, the magnetic binding force of the magnet 404C prevents the cleaning unit 70 from falling off from the cleaning unit mounting portion 40B.

Further, the center of the magnet 404C in the left-right direction is arranged on the right side (downstream side in the moving direction of the cleaning unit 70) with respect to the center of the rotation lever 454 supported by the pin receiving portion 454P. Therefore, when the rotation drive unit 75K rotates the pair of rotation levers 454, the bottom wall 703B of the cleaning unit 70 tilts, thereby reducing the influence of the magnetic binding force of the magnet 404C on the bottom wall 703B. The cleaning unit 70 can be easily moved toward the cleaning position.

Further, in the present embodiment, the cleaning unit rotating portion 45 has a pair of coil springs 455. Therefore, even if the unit drive unit 80 rotates the rotating shaft 451 after the cleaning unit 70 comes into contact with the positioning unit 102S, it is possible to prevent a large load from being applied to the pair of lever support units 453. As a result, the need to control the driving amount of the unit driving unit 80 for bringing the cleaning unit 70 to the cleaning position with high accuracy is reduced.

Further, in the present embodiment, the surface of the roller 32 under resist can be cleaned by the strip-shaped web W. Further, even when the surface of the web W becomes dirty, the web driven roller 71 pays out the web W by the rotation of the web driving roller 73, and the surface of the under-resist roller 32 can be cleaned by the new contact surface.

Further, in the present embodiment, when the cleaning unit mounting portion 40B is arranged on the transport unit frame 40H and the cleaning unit 70 is arranged at the attachment / detachment position, the cleaning unit 70 is integrated with the belt transport unit 40 with respect to the device main body 10. It can be attached and detached. Therefore, the cleaning unit 70 can be easily attached to and detached from the apparatus main body as well as the belt conveying unit 40 that conveys the sheet S to and from the apparatus main body 10.

Further, in the present embodiment, the transport unit frame 40H has a first right frame 404A and a second right frame 404B. Therefore, the rigidity of the right side portion of the transport unit frame 40H can be maintained high. Further, the cleaning unit mounting portion 40B can be formed by using the space below the first right frame 404A (the space between the first right frame 404A and the second right frame 404B). Then, the rotation drive unit 75K has a cleaning position above the first right frame 404A while the cleaning unit 70 comes out from the cleaning unit mounting unit 40B in the right direction (horizontal direction orthogonal to the axial direction of the roller 32 under the resist). A pair of rotating levers 454 are rotated around a rotating shaft 451 so as to reach. Therefore, although the upper part of the cleaning unit 70 arranged at the attachment / detachment position is covered by the first right frame 404A, the cleaning unit 70 comes out from the cleaning unit mounting portion 40B to the right side from the first right frame 404A. Can reach the upper cleaning position.

In the present embodiment, the first detection sensor 803 detects the rotation amount of the pulse plate 802 with reference to the attachment / detachment position (storage position) shown in FIG. 24, so that the rotation amount of the rotation lever 454, that is, The position (cleaning position, separation position) of the cleaning unit 70 is detected. Further, when the second detection sensor 804 detects the cleaning housing 70H, it is detected that the cleaning unit 70 has reached the cleaning position. When the pair of guide rollers 705 of the cleaning unit 70 come into contact with the pair of positioning portions 102S, the rotation of the rotation lever 454 is restricted by the unit fulcrum pin 70P, but the cleaning unit 70 reaches the cleaning position in the control unit 90. After that, the unit drive unit 80 is controlled to slightly rotate the rotating shaft 451. At this time, since the coil spring 455 is interposed between the rotary lever 454 and the lever support portion 453, the coil spring 455 is compressively deformed between the rotary lever 454 and the lever support portion 453 to rotate the lever. It is prevented (regulated) that the rotational force of the lever support portion 453 by the unit drive unit 80 is applied to the rotary lever 454 in a state where the rotation of the rotary lever 454 around the rotary shaft 451 is stopped. In this way, even after the cleaning unit 70 has reached the cleaning position is detected by the first detection sensor 803 and the second detection sensor 804, the rotation shaft 451 can be slightly rotated, so that the rotation shaft 451 can be rotated back and forth. The difference (error) in the mounting position of the moving lever 454 can be absorbed, and the cleaning unit 70 can be reliably arranged in the cleaning position. As a result, the pressing force of the pressing roller 72 against the resisted roller 32 can be stably maintained.

FIG. 32 is graphs (A), (B) and (C) showing the nip load distribution of the resist roller pair. FIG. 33 is a cross-sectional perspective view of another resist roller pair and cleaning unit 70Z compared to the present embodiment. FIG. 32 (A) specifies the axial distribution of the nip load (pressure) applied between the resist upper roller 31 and the resist lower roller 32 in a state where the pressing roller 72 is not in contact with the resist lower roller 32. There is. On the other hand, FIG. 32 (B) shows the distribution of the same nip load in the configuration shown in FIG. 33. In the cleaning unit 70Z of FIG. 33, the contact rollers 72H are fixed to both ends of the pressing roller shaft 72S of the pressing roller 72 in the axial direction. The contact roller 72H regulates the distance between the shafts of the resist lower roller 32 and the pressing roller 72 by abutting against the shaft 32S of the resist lower roller 32, and regulates the pressing force of the pressing roller 72 against the resist lower roller 32. In this way, when the pressing roller 72 is positioned with respect to the resist lower roller 32 by bringing a part of each other into contact with each other, as shown in FIG. 32 (B), the resist upper roller 31 and the resist lower roller 32 Both ends of the nip load between are likely to increase significantly. This phenomenon is caused by the pressing force of the pressing roller 72 against the resist lower roller 32 strongly pressing both ends of the resist lower roller 32 against both ends of the resist upper roller 31. In this case, since the nip load at both ends of the resist roller pair in the axial direction is excessive as compared with the central portion, the transport speed of the sheet S differs in the axial direction, and wrinkles are likely to occur in the sheet S.

On the other hand, in the present embodiment, as shown in FIG. 31, the positioning portion 102S provided at a position different from the resist lower roller 32 receives the unit fulcrum pin 70P of the cleaning unit 70 under the resist of the pressing roller 72. The position with respect to the roller 32 is regulated. As a result, as shown in FIG. 32C, an increase in the nip load of the resist roller pair is suppressed as compared with the cleaning unit 70Z, and the sheet is stably conveyed by the resist roller pair.

In the present embodiment, when double-sided printing is performed in the image forming apparatus 1, the cleaning unit 70 cleans the roller 32 under the resist. As described above, the sheet S on which the image is formed on the front surface in the double-sided printing operation is carried into the resist roller section 30 again with the front and back surfaces inverted through the sheet inversion section 15 and the third transport path 13. .. At this time, when the ink of the image formed on the surface adheres to the surface of the PFA tube of the under-resist roller 32, the ink adheres to the tip of the next sheet S from the under-resist roller 32, and sheet stains occur. Further, when the ink adhering to the resist lower roller 32 is transferred to the resist upper roller 31, the ink adheres to the surface of the next sheet S, which causes an image defect on the printed image. Therefore, in the present embodiment, when the back surface of the sheet S during double-sided printing passes through the resist lower roller 32, the ink adhering to the resist lower roller 32 is cleaned by the web W of the cleaning unit 70. Therefore, the control unit 90 arranges the cleaning unit 70 at the cleaning position corresponding to the execution of double-sided printing, while arranging the cleaning unit 70 at the separated position during single-sided printing. As a result, it is possible to clean the roller 32 under resist for a long period of time even with a web roll WR having a limited length, and it is possible to make the web roll WR compact and reduce the size of the cleaning device 7. It becomes.

Further, when the image is formed under the condition that the surface of the resist lower roller 32 is not easily soiled as in single-sided printing, by arranging the cleaning unit 70 at a separated position, the cleaning unit 70A is placed on the resist lower roller 32. It is possible to reduce the load on the roller 32 under the resist due to the contact, and to suppress unnecessary feeding of the web W.

On the other hand, when it is detected from the detection result of the third detection sensor 813 of the web sending mechanism 81 that the web roll WR is completely unwound from the web driven roller 71, the control unit 90 sends a replacement message of the cleaning unit 70 to the image forming apparatus. It is displayed on a display unit (not shown) of 1. When the operator instructs the operation unit (not shown) of the image forming apparatus 1 to perform the replacement work of the cleaning unit 70, the control unit 90 controls the moving mechanism 75 to move the cleaning unit 70 to the attachment / detachment position. After that, the operator pulls out the transport unit frame 40H forward from the main body frame 100 of the apparatus main body 10, removes the cleaning unit 70 from the cleaning unit mounting portion 40B of the transport unit frame 40H, and removes a new cleaning unit 70 from the transport unit frame 40H. It is mounted on the cleaning unit mounting portion 40B of. In this embodiment, as described above, the cleaning unit cleans the state of the web roll WR held by the web driven roller 71 through the opening formed between the side wall 703A and the bottom wall 703B in FIG. It can be visually recognized from the outside of the 70. Therefore, when the operator pulls out the transport unit frame 40H from the main body frame 100 of the apparatus main body 10, the remaining amount of the web roll WR of the cleaning unit 70 stored in the transport unit frame 40H is pulled out from the transport unit frame 40H. It can be seen from the right side. In other words, in the present embodiment, the cleaning unit mounting portion 40B is the right side portion of the transport unit frame 40H so that the right side portion of the cleaning unit 70 in which the web roll WR is exposed to the outside of the cleaning housing 70H can be visually recognized. It is located in.

In the present embodiment, when the cleaning unit 70 is integrally detached from the apparatus main body 10 together with the transport unit frame 40H, a part of the drive transmission system (device) between the rotation drive unit 75K and the pair of rotation levers 454. The engagement between the main body 10G and the unit drive output gear 805) is cut off. As a result, the pair of rotating levers 454 can rotate around the rotating shaft 451. Therefore, when the operator removes the old cleaning unit 70 from the cleaning unit mounting portion 40B, the pair of rotating levers 454 can rotate so as to send the cleaning unit 70 to the outside of the cleaning unit mounting portion 40B. In other words, the pair of rotating levers 454 rotate around the rotating shaft 451 so as to assist the pair of unit fulcrum pins 70P of the cleaning unit 70 from being detached from the pair of pin receiving portions 454P. As a result, the operator can easily separate the pair of unit fulcrum pins 70P of the cleaning unit 70 from the pair of pin receiving portions 454P. As a result, the cleaning unit 70 can be easily removed from the transport unit frame 40H of the belt transport unit 40.

The cleaning device 7 according to the embodiment of the present invention and the image forming device 1 provided with the cleaning device 7 have been described above. According to such a configuration, the image forming apparatus 1 can stably form an image while stably cleaning the surface of the roller 32 under the resist. The present invention is not limited to the above embodiment, and the following modified embodiments can be adopted.

(1) In the above embodiment, the cleaning unit 70A of the cleaning unit 70 has the web W, but the cleaning unit 70A for cleaning the roller 32 under the resist is not limited to the web W, and the resist. Other cleaning members such as a sponge roller and a brush roller that come into contact with the lower roller 32 may be included.

(2) Further, in the above embodiment, the roller under resist 32 is used as the transfer roller to be cleaned by the cleaning unit 70, but the transfer roller may be another roller that conveys the sheet S.

(3) Further, in the above embodiment, the image forming unit 50 has been described in the embodiment of the inkjet method, but the image forming unit 50 may be to which another image forming method such as a known electrophotographic method is applied. ..

1 Image forming apparatus 10 Device main body 100 Main body frame 100G Guide part 101 Guide frame 101R 1st guide surface 102 Resist frame 102R 2nd guide surface 102S Positioning part 20 Feeding part 30 Resist roller part 30H Resist housing 31 Resist top roller (upper resist) roller)
32 Resist lower roller (conveyor roller, lower resist roller)
40 Belt transport unit (conveyor unit)
40A Transport unit mounting part 40B Cleaning unit mounting part (unit housing part)
40G rotation input gear 40H Conveyance unit frame 401 Front frame (unit frame)
402 Rear frame (unit frame)
404A 1st right frame (upper connection frame)
404B 2nd right frame (lower connection frame)
404C magnet (magnetic member)
41 Conveying belt (conveying part)
45 Cleaning unit Rotating part 451 Rotating shaft 452 Rotating gear 453 Lever support part (fixing member)
454 Rotating lever (support member)
454P pin receiving part (shaft branch)
455 Coil spring 50 Image forming part 60 Curl straightening part 7 Cleaning device 70 Cleaning unit 70A Cleaning part 70H Cleaning housing 70P Unit fulcrum pin (housing shaft part)
701 Front wall 701 (wall part)
702 Rear wall 702 (wall part)
703B Bottom wall 704 Seat member 705 Guide roller (guide roller)
71 Web driven roller (feeding roller)
711 Unit input gear 72 Pressing roller 73 Web drive roller (winding roller)
75 Movement mechanism 75K Rotation drive unit 80 Unit drive unit 801 Drive motor output shaft 802 Pulse plate 803 1st detection sensor 804 2nd detection sensor 805 Unit drive output gear 81 Web delivery mechanism (web drive mechanism)
811 Solenoid 812 Rotating arm 813 Third detection sensor 90 Control unit W Web WR Web roll

Claims (15)

A cleaning device that is rotatably supported by the main body of an image forming device and can clean the surface of a transport roller that transports a sheet.
A cleaning unit having a contact surface extending along the axial direction of the transport roller and having the contact surface abutting against the surface of the transport roller from below to clean the surface, and a cleaning housing supporting the cleaning portion. And, with a cleaning unit,
It is a moving mechanism that can move the cleaning unit between the cleaning position and the attachment / detachment position below the cleaning position, and allows the cleaning unit to come into contact with the transport roller at the cleaning position. In the attachment / detachment position, the cleaning unit is arranged downward with respect to the transfer roller, and the cleaning unit is allowed to be attached / detached to / from the apparatus main body.
The device body is arranged at a position different from that of the transport roller, and abuts on the cleaning unit that has been moved to the cleaning position by the moving mechanism to regulate the relative position between the cleaning unit and the transport roller. A positioning unit that positions the cleaning unit so that the cleaning unit can clean the transport roller,
A cleaning device. The cleaning housing
A pair of wall portions that are arranged to face each other in the axial direction of the transport roller and support the cleaning portion.
It has a pair of columnar guide members projecting from the outer surfaces of the pair of wall portions in the axial direction.
The cleaning device according to claim 1, wherein the positioning portion has an inner peripheral surface along the outer peripheral surface of the pair of guide members and comprises a recess for receiving the guide member. The cleaning housing further has a pair of housing shafts projecting in the axial direction from the outer surfaces of the pair of wall portions at positions different from the pair of guide members.
The moving mechanism
A unit accommodating portion for accommodating the cleaning unit arranged at the detachable position,
A pair of support members arranged in the unit accommodating portion and capable of supporting the cleaning housing so as to sandwich the cleaning housing from both sides in the axial direction, and the pair of support members hold the housing shaft portion. A pair of support members each having a shaft support that receives and rotatably supports the housing shaft.
The cleaning unit is arranged above the shaft support so that the cleaning unit moves between the cleaning position and the attachment / detachment position while the pair of housing shafts are pivotally supported by the pair of shaft support. A rotary drive unit that rotates the pair of support members around a first central axis parallel to the axial direction, and the cleaning unit maintains a posture in which the cleaning unit faces upward. A rotation drive unit that rotates the pair of support members while allowing the pair of housing shaft portions to rotate relative to the pair of shaft support portions.
The cleaning device according to claim 2. The pair of guide members are supported by the pair of wall portions above the housing shaft portion, and are supported by a pair of guide rollers each including an outer peripheral surface that is rotatable around a second central axis parallel to the axial direction. There,
The moving mechanism extends vertically from the cleaning unit arranged at the attachment / detachment position at one end side in the width direction orthogonal to and horizontally in the axial direction, at intervals from each other in the axial direction, and vertically. A pair of guide portions arranged in the above, and allowing the pair of guide rollers to come into contact with each other as the pair of support members rotate around the first central axis, and the cleaning unit is set to the cleaning position. The cleaning device according to claim 3, further comprising a pair of guide portions for guiding to and from the attachment / detachment position. With the cleaning unit arranged at the attachment / detachment position, the pair of support members are arranged so as to extend downward from the first central axis, and the shaft support portion is one end of the support member in the width direction. The side portion on the side has a shape that is notched downward on the other end side opposite to the one end side in the width direction, and the housing shaft portion is received along a direction orthogonal to the axial direction. ,
The rotation drive unit centers the pair of support members on the first center so that the housing shaft portion moves upward and on one end side in the width direction from the state where the cleaning unit is arranged at the attachment / detachment position. The cleaning device according to claim 4, wherein the cleaning unit is moved to the cleaning position by rotating around an axis. When the cleaning unit arranged at the attachment / detachment position is viewed from a direction parallel to the axial direction, the center of the housing shaft portion supported by the shaft support portion is below the first central axis and in the width direction. It is arranged on one end side, and the center of gravity of the cleaning unit is arranged on the one end side in the width direction with respect to the housing shaft portion.
When the rotation driving unit rotates the pair of support members around the first central axis from the state where the cleaning unit is arranged at the attachment / detachment position, the cleaning unit is moved by the weight of the cleaning unit to the housing shaft. The cleaning device according to claim 5, wherein the pair of guide rollers come into contact with each of the pair of guide portions by tilting the portion toward one end side in the width direction. The cleaning housing is made of a magnetic material and has a connecting wall that connects the pair of wall portions along the axial direction.
The sixth aspect of claim 6, wherein the unit accommodating portion has at least one magnetic member which is arranged to face the connection wall of the cleaning housing arranged at the attachment / detachment position and generates a magnetic field for holding the cleaning unit. Cleaning equipment. The connecting wall of the cleaning housing is a bottom wall that defines the bottom of the cleaning housing.
The at least one magnetic member is arranged so as to face the bottom wall of the cleaning unit arranged at the attachment / detachment position.
When the cleaning unit arranged at the attachment / detachment position is viewed from a direction parallel to the axial direction, the center of the magnetic member in the width direction is wider than the center of the housing shaft portion supported by the shaft support portion. The cleaning device according to claim 7, which is arranged on one end side in the direction. The cleaning part
A strip-shaped web having a contact surface capable of contacting the transport roller, and
A pressing roller that presses the web against the transport roller,
A feeding roller for feeding the web and a winding roller for winding the web so that the portion of the web in contact with the transport roller changes.
Have,
Any one of claims 1 to 8, further comprising a web drive mechanism connected to the cleaning unit arranged at the cleaning position and rotationally driving at least the take-up roller among the take-out roller and the take-up roller. The cleaning device described in. The moving mechanism can move the cleaning unit to a separation position between the cleaning position and the attachment / detachment position in addition to the cleaning position and the attachment / detachment position. At the separation position, the cleaning unit can move the cleaning unit. The cleaning device according to claim 9, wherein the cleaning unit is arranged downward with respect to the transport roller and the connection between the cleaning unit and the web drive mechanism is released. With the device body
A transport roller that transports the sheet and
An image forming unit that forms an image on the sheet,
The cleaning device according to any one of claims 1 to 10, capable of cleaning the transport roller.
An image forming apparatus. It includes a transport unit that transports the sheet at a position different from that of the transport roller, and can be mounted on the apparatus main body along a first direction parallel to the axial direction and in a second direction opposite to the first direction. A transport unit that can be detached from the main body of the device is further provided along the line.
The unit accommodating portion is arranged in the transport unit, and when the cleaning unit is arranged in the detachable position, the cleaning unit can be attached to and detached from the apparatus main body integrally with the transport unit. The image forming apparatus according to claim 11. When the cleaning unit is integrally detached from the apparatus main body together with the transport unit, a part of the drive transmission system between the rotation drive unit and the pair of support members is cut, so that the cleaning unit 12. The image of claim 12, wherein the pair of support members are rotatable about the first central axis so as to assist the pair of housing shafts in being detached from the pair of shaft supports. Forming device. The transport unit is
A pair of unit frames arranged so as to face each other in the axial direction and supporting the transport portion,
A lower connecting frame that connects the pair of unit frames to each other along the axial direction and supports the cleaning unit arranged at the attachment / detachment position from below.
Above the lower connecting frame, the pair of unit frames are connected to each other along the axial direction, and the lower connecting frame covers at least a part of the cleaning unit arranged at the attachment / detachment position. An upper connecting frame that defines the unit housing with and
Have,
The rotation drive unit holds the pair of support members so that the cleaning unit reaches the cleaning position above the upper connection frame while coming out of the unit accommodating unit in a horizontal direction orthogonal to the axial direction. The image forming apparatus according to claim 12 or 13, which is rotated around the first central axis. Further, an upper resist roller for transporting the sheet toward the image forming portion according to the image forming timing in the image forming portion is further provided.
The transport roller is arranged below the upper resist roller to form a nip portion through which the sheet passes with the upper resist roller, and transports the sheet toward the image forming portion in accordance with the image formation timing. Configure the lower resist roller to
The image forming apparatus according to any one of claims 11 to 14, wherein the cleaning device cleans the surface of the lower resist roller.

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