JP2020196620A - Cleaning device and image formation apparatus - Google Patents

Abstract

To provide a cleaning device which can clean an adherent solid content with a cleaning member even when the solid content derived from a recording material adheres to the surface of a sheet conveyance member, and provide an image formation apparatus having the same.SOLUTION: A register roller part for conveying a sheet to an image formation part includes a register lower roller 32. There may be a case where a solid content GR formed from drying and solidifying of ink may adhere to a roller surface 32f of the register lower roller 32. A web W can be brought into contact with a lower side of the register lower roller 32. The web W contacts the register lower roller 32 by being pressed by a press roller 72. The contact surface contacting the register lower roller 32 of the web W is an uneven surface rougher than the roller surface 32f of the register lower roller 32. At the cleaning, the web W relatively moves with respect to the roller surface 32f. The solid content GR is removed by a web face Wf.SELECTED DRAWING: Figure 10

Description

The present invention relates to a cleaning device for cleaning sheet transport members such as a transport roller and a transport belt for transporting sheets, and an image forming apparatus including the cleaning device.

An image forming apparatus such as a printer includes a sheet conveying unit that conveys a sheet to an image forming unit in which an image forming process is executed. The sheet transport unit includes, for example, a pair of resist rollers having a length corresponding to the width of the sheet to be transported. The resist roller pair forms a nip 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 at an appropriate image formation timing at the image formation position.

As another example of the sheet transport unit, there is also a configuration including a plurality of support rollers and a transport belt stretched between the plurality of support rollers. In the sheet transport unit having this configuration, the transport belt is driven at a predetermined timing to transport the sheet placed on the transport belt to the image forming section.

By the way, due to the transfer of the sheet, the surface of the sheet transfer member such as the resist roller and the transfer belt may be contaminated. If the surface of the sheet transport member is contaminated, the sheet to be printed may have a problem of image stain. Patent Document 1 discloses a cleaning mechanism having a configuration in which a web is brought into contact with a resist roller and a voltage of a predetermined polarity is applied to a pressure roller for pressing the web against the resist roller. In this mechanism, by applying the above voltage, the polarity of the paper powder adhering to the surface of the resist roller and the polarity of the web are reversed, so that the paper dust is highly efficiently adsorbed on the web and the surface of the resist roller is raised. I'm trying to clean it.

Japanese Unexamined Patent Publication No. 2006-117420

However, a recording material for printing other than paper powder may adhere to the surface of the sheet transport member. For example, when performing double-sided printing with an inkjet image forming apparatus, ink may adhere to the surface of the sheet transport member. In this case, the technique disclosed in Patent Document 1 may not be able to sufficiently clean the surface of the sheet transport member. For example, during the double-sided printing, the ink may dry and solidify and adhere to the surface of the sheet transport member, and it is difficult to sufficiently clean the surface of the paper transport member by the technique disclosed in Patent Document 1.

Further, even in an image forming apparatus that forms an image using toner, the toner may be cooled and solidified and adhered to the surface of the paper transport member when performing double-sided printing. It is difficult to sufficiently clean the solid content derived from the toner adhered in this way by the technique disclosed in Patent Document 1 above.

The present invention is a cleaning device capable of cleaning the adhered solids with a cleaning member even when solids derived from a recording material adhere to the surface of the sheet transport member, and an image forming apparatus including the cleaning device. The purpose is to provide.

The cleaning device according to one aspect of the present invention cleans the surface of the sheet transport member that transports the sheet in the image forming apparatus that executes the image forming process using the recording material to which the solid content derived from the recording material adheres. A cleaning device including a cleaning member capable of contacting the surface of the sheet transport member, and the contact surface of the cleaning member that contacts the surface of the sheet transport member has irregularities that are coarser than the surface of the sheet transport member. It is a surface, and the cleaning member moves relative to the surface of the sheet transport member during the cleaning, and the uneven surface of the contact surface moves relative to the surface of the sheet transport member during the relative movement. It is an uneven surface on which the adhering solid content can be peeled off.

According to this cleaning device, the contact surface of the cleaning member with the surface of the sheet transport member is an uneven surface rougher than the surface of the sheet transport member. Therefore, when the cleaning member moves relative to the surface of the sheet transport member during the cleaning, the solid content adhered to the surface of the sheet transport member is stripped off by the unevenness of the contact surface of the cleaning member. , Trapped in the recess on the contact surface. Therefore, it is possible to prevent the solid matter derived from the recording material from remaining attached to the surface of the sheet transport member.

In the above cleaning device, it is desirable that the cleaning member is a fiber sheet formed of fibers.

When a fiber sheet is used as the cleaning member, the absorbability of the liquid can be improved. Therefore, if a fiber sheet is used as the cleaning member, even if a liquid recording material adheres to the surface of the sheet transport member together with the solid content, the recording material can also be cleaned by the cleaning member.

In the above cleaning device, it is desirable that the cleaning member is a non-woven fabric.

Generally, the non-woven fabric has a porous structure. Therefore, by adopting the non-woven fabric as the cleaning member, the contact surface is provided with a large number of irregularities, which is advantageous for stripping the solid content and adsorbing the liquid recording material. Is also advantageous.

In the cleaning device, the recording material is ink, and the solid content may be attached to the surface of the sheet transport member by drying and solidifying the ink.

As described above, when the ink dries and solidifies and the solid content adheres to the surface of the sheet transport member, it is difficult to remove the solid content even if the cleaning member having a smooth surface is brought into contact with the ink. However, by adopting the cleaning member having the above-mentioned structure, it is possible to surely peel off the solid content in which the ink is dried and solidified.

In the cleaning device, the cleaning member is a band-shaped web forming the contact surface that abuts on the sheet transport member, and the cleaning device further presses the web against the sheet transport member. It is desirable to include a feeding roller for feeding out the web and a winding roller for winding the web so that the portion of the web in contact with the sheet transport member changes.

According to this cleaning device, it is possible to perform a cleaning operation while updating the contact surface while pressing the contact surface of the web against the sheet transport member with a pressing roller.

The image forming apparatus according to another aspect of the present invention includes an image forming unit that executes an image forming process using a recording material, and a sheet conveying member that conveys a sheet to the image forming unit and comes into contact with the sheet. It is provided with a transport unit and the above-mentioned cleaning device.

According to this image forming apparatus, since the cleaning apparatus capable of exerting the above-mentioned effect is provided, even if the solid content adheres to the surface of the sheet transport member, the adhered solid content is removed. It can be cleaned with a cleaning member. Therefore, even if the solid content derived from the recording material adheres to the surface of the sheet transport member, it can be reliably cleaned and the occurrence of image stain defects can be suppressed.

In the above image forming apparatus, it is desirable that the resist roller pair for conveying the sheet toward the image forming position in accordance with the image forming timing is provided, and the sheet conveying member is one of the resist roller pairs. ..

According to this image forming apparatus, even when the sheet transport member is one roller of a pair of resist rollers and the solid content adheres to the surface of the rollers, the cleaning member having the above configuration is adopted. Therefore, it is possible to surely peel off the solid content.

In the above image forming apparatus, it is desirable that the outer peripheral side portion in the radial direction of the one roller is formed of a resin material, and the surface thereof is formed on a surface smoother than the surface of the cleaning member.

According to this configuration, even when the solid content adheres to the relatively smooth surface of the one roller, the solid content is surely removed by contacting the cleaning member having a rough surface as described above. It can be stripped off.

The image forming apparatus further includes a sheet reversing portion that inverts the front and back sides of the sheet on which an image is formed on one surface of the image forming portion and conveys the image to the sheet conveying portion. It is desirable that it is arranged at a position where it comes into contact with a sheet on which an image is formed on one surface.

As described above, in the case of an image forming apparatus having a sheet reversing portion and having a double-sided printing function, solids derived from the recording material used in the above image forming tend to adhere to the surface of the sheet conveying member. Even in such a case, it is possible to reliably clean the recording material adhering to the surface of the sheet transport member with the cleaning member as described above.

When each of the above configurations is adopted, even if the solid content derived from the recording material adheres to the surface of the sheet transport member, the adhered solid content can be cleaned by the cleaning member.

It is a schematic cross-sectional view which shows the internal structure of the image forming apparatus which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the structure of the peripheral part of a resist roller part and a cleaning unit. It is a perspective view which shows the external structure of a cleaning unit. It is a perspective view which shows the external structure of a cleaning unit. It is a perspective view which shows the external structure of a cleaning unit. It is sectional drawing which shows the VI-VI line cross section of FIG. It is a figure which shows the resist roller part and the cleaning unit in the state which the cleaning unit is in a detachable position. It is a partial cross-sectional view which shows the resist roller part and the cleaning unit in a state where the cleaning unit is pushed up slightly diagonally upward to the right from the attachment / detachment position. It is a partial cross-sectional view which shows the resist roller part and a cleaning unit in a state which a cleaning unit is in a cleaning position. It is a schematic diagram which shows the roller on the resist, the roller under the resist, the pressing roller and the web. It is a schematic diagram which shows the contact part between a roller under resist and a web. It is sectional drawing of the web with solid content attached to the surface of the web. It is a schematic diagram which shows the structure of the sheet transport part and the cleaning unit in the image forming apparatus which concerns on 2nd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The forms described below are examples of the present invention, and the present invention is not limited to the following forms except for its essential configuration.

[First Embodiment]
<Overall configuration of image forming device>
FIG. 1 is a diagram showing an internal structure of the image forming apparatus 1 according to the first embodiment of the present invention. The image forming apparatus 1 shown in FIG. 1 is an inkjet recording apparatus that ejects water-based ink droplets (recording material) 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 (sheet conveying unit) 30, a belt conveying 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 feeds out the uppermost sheet S of the sheet bundle housed in the paper feed cassette 21 one by one and sends it out to the first transport path 11.

The sheet S fed into the first transport path 11 reaches the resist roller portion 30 arranged on the downstream side of the first transport path 11 by the first transport roller pair 111 provided in the first transport path 11. Be transported. A paper feed tray 24 is arranged on the right side surface of the apparatus main body 10, and a sheet S can be manually 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 introduced via 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. Details of the resist roller unit 30 will be described later.

When the tip of the sheet S conveyed by the resist roller unit 30 comes into contact with the outer peripheral surface 411 of the transfer belt 41, the sheet S is conveyed in the sheet transfer direction A2 while being held on the outer peripheral surface 411 by the drive of the transfer belt 41. Ru. The sheet transport direction A2 is a direction from the right side to the left side in the left-right direction.

The belt transport unit 40 is arranged below the image forming unit 50 so as to face the line head 51. 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 under the image forming unit 50. The belt transport unit 40 includes a transport belt 41 and a suction unit 43.

The transport belt 41 is an endless belt having a width in the front-rear direction (direction orthogonal to the paper surface of FIG. 1) 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. More specifically, the transport belt 41 holds the sheet S on the outer peripheral surface 411 in a predetermined transport region facing the line head 51 of the image forming unit 50, and transports the sheet S in the sheet transport direction A2. An image forming position on the line head 51 of the image forming unit 50 on which the image forming process is executed is set on the orbital moving 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. The first support roller 421 is a drive roller that extends along the front-rear direction that is the width direction of the transport belt 41, and is arranged on the downstream side of the suction portion 43 in the sheet transport direction A2. 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. As the transport belt 41 goes around, the sheet S held on the outer peripheral surface 411 is transported in the sheet transport direction A2.

The second support roller 422 is a belt speed detection roller that extends along the front-rear direction, and is arranged on the upstream side of the suction portion 43 in the sheet transport direction A2. The second support roller 422 cooperates with the first support roller 421 to face a region facing the line head 51 on the outer peripheral surface 411 of the transport belt 41 and a region facing the suction portion 43 on the inner peripheral surface 412 of the transport belt 41. It is arranged so that the flatness with and is maintained. Here, in the outer peripheral surface 411 of the transport belt 41, a region facing the line head 51 and between the first support roller 421 and the second support roller 422 is for holding and transporting the sheet S. It becomes the predetermined transport area of. The second support roller 422 is driven to rotate in conjunction with the rotation of the transport belt 41. A pulse plate (not shown) is attached to the second support roller 422. This pulse plate rotates integrally with the second support roller 422. By measuring the rotation speed of the pulse plate, the rotation speed of the transport belt 41 is detected.

The third support roller 423 is a tension roller extending in the front-rear direction, and applies tension to the transport belt 41 so that the transport belt 41 does not bend. The third support roller 423 rotates drivenly in conjunction with the rotation of the transport belt 41. Each of the pair of fourth support rollers 424 is a guide roller extending in the front-rear direction, and guides the transfer belt 41 so that the transfer belt 41 passes under the suction portion 43. The pair of fourth support rollers 424 are driven to rotate in conjunction with the rotation of the transport belt 41. 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 brings the sheet S held on the outer peripheral surface 411 of the transport belt 41 into close contact with the outer peripheral surface 411 of the transport belt 41 by generating a negative pressure with the transport 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 is arranged so as to face the region between the first support roller 421 and the second support roller 422 on the inner peripheral surface 412 of the transport belt 41. The belt guide member 431 is a plate-shaped member having substantially the same width dimension as the length in the width direction (front-back direction) of the transport belt 41. The belt guide member 431 constitutes the upper surface portion of the suction housing 432 and has substantially the same shape as the suction housing 432 when viewed from above. 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.

Further, the belt guide member 431 has a plurality of grooves formed on the belt guide surface facing the inner peripheral surface 412 of the transport belt 41. Each groove is formed corresponding to the suction hole of the transport belt 41. Further, the belt guide member 431 has a through hole provided corresponding to each groove. The through hole is a hole that penetrates in each groove in the thickness direction of the belt guide member 431, and interlocks with the suction hole of the transport belt 41 through each groove.

The suction portion 43 configured as described above has a suction force by sucking air from the space above the transport belt 41 through the groove portion and the through hole of the belt guide member 431 and the suction hole of the transport belt 41. To generate. Due to this suction force, an air flow (intake air) 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. That is, the space surrounded by the suction housing 432 and the belt guide member 431 becomes the suction space 432A. The suction space 432A communicates with the suction hole of the transport belt 41 through the groove portion and the through hole of 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 above the belt transport unit 40. Specifically, the image forming unit 50 is arranged above the belt transport unit 40 so as to face the outer peripheral surface 411 of the transport belt 41. 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 unit 50 uses an inkjet method for forming an image, and ejects water-based ink droplets (recording material) 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. Each of the line heads 51Bk, 51C, 51M, and 51Y 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, and displays an image on the sheet S. Form. As a result, an image is formed on the sheet S.

The sheet S on which the image is formed is conveyed by the transport belt 41, and is carried into the curl correction section 60 while being guided by the discharge guide section 44. The curl correction portion 60 is arranged on the downstream side of the sheet transport direction A2 of the transport belt 41 with the 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 applied to the sheet S, the sheet S for which the image forming process on the front surface side has been 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 switched back. The sheet S whose front and back sides are reversed by the sheet reversing portion 15 is sent to the third transport path 13, and is back-fed by the third transport roller pair 131 provided in the third transport path 13. After that, the sheet S is resupplied onto the outer peripheral surface 411 of the transport belt 41 again in a state where the front and back sides are reversed via the resist roller portion 30. The resupplied sheet S is subjected to image forming processing on the back surface side by the image forming portion 50 while being conveyed by the conveying belt 41. 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.

<Structure of resist roller part and its peripheral part>
FIG. 2 is a diagram showing the structure of the resist roller portion 30 and its peripheral portion. As shown in FIG. 2, the resist roller portion 30 has a resist housing 30H and a resist roller pair including a resist upper roller 31 and a resist lower roller (sheet transport member) 32. 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 nip portion of the resist roller pair composed of the resist upper roller 31 and the resist lower roller 32 in the resist housing 30H. 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 roller 31 is a metal roller such as an aluminum alloy. The under-resist roller 32 is formed on the outer periphery (diametrically outer peripheral side portion) of the roller base material made of rubber such as EPDM (ethylene propylene / diene rubber), for example, with PFA (ethylene tetrafluoroethylene / perfluoroalkoxyethylene). It is configured by coating a tube having high water repellency made of polymer resin; resin material) or the like. The resist lower roller 32 forms a nip portion through which the sheet S passes with the resist upper roller 31, and conveys the sheet S toward the image forming portion 50 in accordance with the image forming timing.

As shown in FIG. 2, the virtual 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.

When the above-mentioned double-sided printing is performed, the single-sided printed sheet S is turned upside down and carried into the nip portion of the resist roller pair. Therefore, the under-resist roller 32 comes into contact with the printed surface of the sheet S, and undried ink may adhere to the surface of the under-resist roller 32. In this case, when the subsequent sheet S passes through the resist roller pair, there is a problem that the ink adhering to the resist lower roller 32 is transferred. Further, the resist lower roller 32 located on the lower side of the resist roller pair is a roller to which foreign matter including paper dust easily adheres.

In view of the above circumstances, the image forming apparatus 1 of the present embodiment includes a cleaning unit (cleaning apparatus) 70 and a moving mechanism 75. The cleaning unit 70 is capable of cleaning the surface of the roller 32 under the resist. Although the detailed structure will be described later, the cleaning unit 70 includes a web driven roller 71, a pressing roller 72, a web driving roller 73, a cleaning housing 70H that pivotally supports these rollers 71 to 73, and a web W.

The web W is composed of a band-shaped member that abuts on the surface of the roller 32 under resist to form a contact surface for cleaning the surface. The web W is made of a cloth material such as a non-woven fabric, and is fitted onto the web driven roller 71 in the form of a web roll WR previously wound in a roll shape. The web W is ejected in a fixed amount from the web roll WR wound around the web driven roller 71, and is wound around the web drive roller 73 via the pressing roller 72. The web W is stretched between the web driven roller 71, the pressing roller 72, and the web driving roller 73 without slack.

The moving mechanism 75 (FIG. 2) is a mechanism that enables the cleaning unit 70 to be moved between the cleaning position (FIG. 2) and the attachment / detachment position (FIG. 7) below the cleaning position. The moving mechanism 75 allows the web W of the cleaning portion 70A to come into contact with the resist lower roller 32 at the cleaning position, and the cleaning portion 70A is arranged downward with respect to the resist lower roller 32 at the attachment / detachment position. Also, the cleaning unit 70 is allowed to be attached to and detached from the device main body 10. Further, the moving mechanism 75 can position the cleaning unit 70 at an intermediate position between the cleaning position and the attachment / detachment position. At this separation position, the cleaning unit 70A is separated downward from the resist lower roller 32, and the connection between the cleaning unit 70 and the web feeding mechanism is released.

The moving mechanism 75 includes a cleaning unit rotating unit 45 and a unit driving unit 80 that rotate the cleaning unit 70 so as to change its posture between the cleaning position and the attachment / detachment position. The cleaning unit rotating portion 45 includes a rotating shaft 451 supported by a transport unit frame 40H that holds the belt transport unit 40, and a pair of front and rear rotating levers 452 attached to the front and rear of the rotating shaft 451. ..

The unit drive unit 80 includes a drive motor (not shown) and generates a driving force for rotating the rotation shaft 451 around its central axis. Along with the rotational drive of the drive motor, the rotary shaft 451 rotates by a predetermined angle. A control unit 90 is connected to the drive motor of the unit drive unit 80. The drive motor is rotationally driven according to a control signal from the control unit 90. The control unit 90 is configured to execute a predetermined operation program in a computer system including, for example, a CPU, ROM, RAM, and the like.

A pin receiving portion 452P (FIG. 8) is formed on the rotating lever 452. The pin receiving portion 452P receives the unit support pin 70P projecting in the front-rear direction of the cleaning unit 70, and rotatably supports the unit support pin 70P. The posture of the cleaning unit 70 is controlled at three positions of the cleaning position, the separation position, and the attachment / detachment position according to the rotation angle of the rotation shaft 451 rotated by the unit drive unit 80. The state shown in FIG. 2 is a cleaning position in which the pressing roller 72 is in contact with the resist lower roller 32 across the web W.

When the cleaning unit 70 is in the separated position, the pressing roller 72 is separated downward so that the web W and the resist lower roller 32 are separated from each other. When the cleaning unit 70 is in the detachable position, the pressing roller 72 is further separated downward.

<Detailed structure of cleaning unit>
3 to 5 are perspective views showing the external structure of the cleaning unit by changing the viewing direction. FIG. 6 is a cross-sectional view showing a VI-VI line cross section of FIG. The cleaning unit 70 includes a cleaning unit 70A and a cleaning housing 70H. The cleaning unit 70A has a contact surface WA extending along the axial direction of the roller 32 under the resist. The cleaning unit 70A is arranged so that the contact surface WA is in contact with the surface of the roller 32 under the resist from below, and the contact surface WA is cleaned so as to wipe the surface.

The cleaning housing 70H supports the cleaning portion 70A. The cleaning housing 70H has a front wall 701 and a rear wall 702, a connection wall 703, a pair of unit support pins 70P, a seat member 704, and a pair of guide rollers 705. 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 connection wall 703 has a side wall 703A forming the upper right side surface of the cleaning housing 70H and a bottom wall 703B forming the bottom surface of the cleaning housing 70H (see FIG. 6).

The pair of unit support pins 70P project from the outer side surfaces of the front wall 701 and the rear wall 702 in the front-rear direction, respectively. The unit support pin 70P is arranged in the lower left portion of the front wall 701 and the rear wall 702. Each unit support pin 70P has a two-stage cylindrical shape in which the outer diameter is reduced from the root portion to the tip portion.

The sheet member 704 is a film-like member forming the left side surface of the cleaning housing 70H, and is fixed to the bottom wall 703B (FIG. 6). The sheet member 704 prevents foreign substances such as paper dust and ink pigments collected in the cleaning unit 70 from being scattered in the apparatus main body 10.

The pair of guide rollers 705 are supported by the front wall 701 and the rear wall 702, respectively, above the unit support pin 70P, and include an outer peripheral surface that is rotatable around a center line parallel to the front-rear direction. The guide roller 705 is arranged in the upper right portion 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 cleaning position, separation position, and attachment / detachment 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). Has. The web W is composed of a strip-shaped member that abuts on the surface of the roller 32 under resist and forms the above-mentioned contact surface WA that cleans the surface. The feeding 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.

As described above, the strip-shaped web W is unwound from the web roll WR wound around the web driven roller 71. In the web roll WR, the remaining amount of the web W 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. Therefore, it is possible to prevent the cleaning unit 70, in which the remaining amount of the web W detached from the apparatus main body 10 during use of the image forming apparatus 1 is small, is accidentally attached to the apparatus main body 10.

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. The pressing roller 72 is located between the web driven roller 71 and the web driving roller 73 on the moving path of the web W. The pressing roller 72 is an elastic roller in which an elastic body 72A is fitted on the peripheral surface of the pressing roller shaft 72S. The pressing roller shaft 72S is a metal shaft, and for example, a shaft made of solid iron can be used. As the elastic body 72A, for example, a sponge member made of a foam of EPDM can be used. When the cleaning unit 70 is arranged at the above-mentioned cleaning position (FIG. 2), the pressing roller 72 abuts on the resist lower roller 32 with the web W in between. At this time, the center of the pressing roller 72 is located on the straight line L. The above-mentioned contact surface WA is a contact portion of the web W with respect to the under-resist roller 32 in the nip portion between the pressing roller 72 and the under-resist roller 32 formed on the straight line L, and extends in a strip shape in the front-rear direction. It is a part.

The web driven roller 71 is a roller capable of driven rotation around the axis of the driven roller shaft 71S. The web driven roller 71 feeds out the web W so that the portion of the web W that abuts on the under-resist roller 32 changes. The web drive roller 73 winds up the unwound web W. The web drive roller 73 is a roller that rotates around the axis of the drive roller shaft 73S, and a rotational driving force is applied to the drive roller shaft 73S from the drive system.

The cleaning unit 70 has a unit input gear 711 (see FIG. 4), an interlocking gear 711T, a transmission gear 712, and a drive roller gear 713 (see FIG. 6) as the drive system described above. 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 inward (back side) from 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 inward of 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.

Although detailed description is omitted, the web W is unwound from the web roll WR by a predetermined amount at a predetermined timing by the web feeding mechanism. The web feeding mechanism has a function of applying a rotational driving force to the driving roller shaft 73S to feed the web W. The web feeding mechanism includes a solenoid as a drive source, and a drive transmission system that converts the retracting motion of the retracting shaft of the solenoid into a rotational force and transmits it to the unit input gear 711.

<Movement form of cleaning unit>
As described above, the cleaning unit 70 of the image forming apparatus 1 according to the present embodiment can be moved between the cleaning position, the separation position, and the attachment / detachment position. The form of each position movement in the cleaning unit 70 will be described with reference to FIGS. 7 to 9. FIG. 7 is a diagram showing the cleaning unit 70 and its peripheral portion in a state where the cleaning unit 70 is in the detachable position. FIG. 8 shows a partial cross section showing the resist roller portion 30 and the cleaning unit 70 in a state where the cleaning unit 70 is pushed up slightly diagonally upward to the right from the attachment / detachment position, and FIG. 9 shows the cleaning unit 70 in the cleaning position. It is a perspective view.

As shown in FIG. 8, the unit support pin 70P of the cleaning unit 70 is engaged with a pin receiving portion 452P provided near the tip of the rotary lever 452. The tip of the rotary lever 452 rotates counterclockwise as the drive motor (not shown) included in the unit drive unit 80 drives the rotary shaft 451 to rotate. Therefore, the cleaning unit 70 is pushed up diagonally upward to the right in conjunction with the rotational operation of the rotary lever 452. Further, when the rotary shaft 451 is driven in the reverse rotation, the rotary lever 452 rotates clockwise, whereby the cleaning unit 70 is lowered to the lower left.

Here, the unit support pin 70P of the cleaning unit 70 is arranged on the lower left side of the center of gravity of the cleaning unit 70. Therefore, when the cleaning unit 70 is pushed up, the cleaning unit 70 takes a posture in which its upper portion is tilted to the right.

Here, as shown in FIG. 7, a guide frame 101 is provided between the resist roller unit 30 and the unit drive unit 80 and diagonally above the cleaning unit 70 to the right. A guide surface 101R composed of a slope is provided on the left side portion of the guide frame 101. The guide surface 101R is a guide surface for guiding the pair of guide rollers 705 provided at the diagonally upper right corner portion of the cleaning unit 70 to the guide surface 102R provided at the lower part of the resist frame 102.

That is, when the cleaning unit 70 is pushed upward by the rotation of the rotation lever 454 from the state of the attachment / detachment position (FIG. 2), the cleaning unit 70 tilts to the right due to the difference between the unit support pin 70P and the center of gravity as described above. As a result, the pair of guide rollers 705 abut on the guide surface 101R and are guided by the guide surface 101R. Then, as the rotation of the rotation lever 454 further progresses, the pair of guide rollers 705 guided by the guide surface 101R and the guide surface 102R are pushed into the positioning portion 102S of the resist frame 102 (see FIG. 9). When the pair of guide rollers 705 are pushed into the positioning portion 102S, the cleaning unit 70 is arranged at the cleaning position, and the relative movement of the cleaning unit 70 with respect to the resist roller portion 30 is stopped.

The separated position of the cleaning unit 70 is a state in which the cleaning unit 70 is at an intermediate position between FIGS. 8 and 9. The separation position can be appropriately set at an arbitrary position where the web W is separated from the roller 32 under the resist.

<Cleaning process by cleaning unit>
The cleaning treatment of the surface of the under-resist roller 32 by the cleaning unit 70 will be described with reference to FIGS. 10 to 12. FIG. 10 is a schematic view showing a roller under resist 32, a pressing roller 72, and a web W in a state where the cleaning unit 70 is in the cleaning position. 11 is an enlarged view showing the A portion of FIG. 10, and FIG. 12 is an enlarged cross-sectional view showing the B portion of FIG. 10.

As shown in FIG. 10, when the sheet S image-formed on one side (one side) is inverted and introduced into the resist roller portion 30, the ink is derived from the surface 32f of the resist lower roller 32. Solid GR may adhere. Here, the solid content GR derived from the ink is an ink that has dried and solidified and adhered to the surface of the roller 32 under the resist (ink pigment or the like).

As shown in FIG. 11, by rotating the resist lower roller 32, the roller surface 32f of the resist lower roller 32 and the web surface Wf of the web W move relative to each other. As the web W moves relative to the roller surface 32f in this way, the solid content GR adhering to the roller surface 32f reaches the nip inlet EN of the cleaning nip N. The cleaning nip N is a nip portion formed by the resist lower roller 32 and the web W pressed by the pressing roller 72 so as to come into contact with the resist lower roller 32. After that, the solid content GR is stripped off by the web surface Wf of the web W composed of the uneven surface as shown in FIG. Then, the solid content GR stripped from the roller surface 32f is trapped in the recess of the web surface Wf.

When the above cleaning process is completed, the web W is sent by the rotational drive of the web drive roller 73 (see FIG. 6). As a result, the new surface of the web W can be brought into contact with the under-resist roller 32 in the next cleaning process.

<Unevenness on the web surface>
The size of the unevenness on the web surface Wf (contact surface) of the web W will be described in comparison with the roller surface 32f of the under-resist roller 32. As shown in FIG. 12, the web surface Wf, which is the surface of the web W on the side of contacting the under-resist roller 32, has a solid content GR (for example, an ink pigment) having a size expected from the ink used in the image forming apparatus 1. It is constructed with an uneven surface that can be peeled off and trapped. In other words, the web surface Wf is composed of a surface that is relatively rough with respect to the roller surface 32f of the resist under-resist roller 32 so that the solid content GR can be stripped and trapped.

On the other hand, the roller surface 32f, which is the outer peripheral surface of the resist lower roller 32, is composed of a surface that is relatively smooth with respect to the web surface Wf. The roller surface 32f of the under-resist roller 32 also has irregularities on the surface microscopically, but is composed of a surface that is relatively smooth with respect to the web surface Wf.

<Effect>
The cleaning unit (cleaning device) 70 according to the first embodiment is a roller surface (sheet transport member) 32 of a resist under-resist roller (sheet transport member) 32 included in a resist roller section (sheet transport section) 30 that transports the sheet S to the image forming section 50. Surface) A mechanism for cleaning 32f. The image forming unit 50 includes a web (cleaning member) W that is capable of performing an image forming process using ink (recording member) and can come into contact with the roller surface 32f of the roller 32 under resist. The solid content GR derived from the ink adheres to the roller surface 32f of the roller 32 under the resist. The web surface (contact surface) Wf of the web W is a rough surface that is rougher than the roller surface 32f of the roller 32 under resist. When cleaning the roller surface 32f of the under-resist roller 32, the web W moves relative to the roller surface 32f of the under-resist roller 32. The uneven surface of the web surface Wf is an uneven surface capable of stripping the solid content GR adhering (fixed) to the roller surface 32f.

By making the web surface Wf of the web W a rough surface that is relatively coarser than the roller surface 32f of the roller 32 under resist, the solid content GR adhering to the roller surface 32f can be easily stripped off. When the roller surface 32f made of a relatively smooth surface and the web surface Wf made of a rough uneven surface are rubbed by the relative movement, if the solid content GR is attached to the roller surface 32f, the solid content GR Is easily scraped off by the unevenness of the web surface Wf. That is, the solid content GR, which is a fine particle supported on the smooth roller surface 32f, has a relatively weak binding force, and when it comes into contact with the uneven surface of the web surface Wf that moves relative to the surface, the solid content GR is stripped from the roller surface 32f. , As shown in FIG. 12, it comes to be trapped in the uneven surface. As described above, it is desirable to use a roller coated with a tube capable of achieving high smoothness, such as a PFA tube, as the under-resist roller 32 in order to facilitate this effect. Further, it is desirable that the web surface Wf is a surface having recesses having a width and depth of a size that allows the solid content GR of the ink pigment or toner to be used to be trapped. According to the cleaning unit 70 according to the present embodiment and the image forming apparatus 1 provided with the cleaning unit 70, it is possible to prevent the solid content GR derived from the ink from remaining attached to the roller surface 32f of the roller 32 under the resist. it can.

In the cleaning unit 70 according to the present embodiment, a fiber sheet formed by using fibers as the web W is adopted. Therefore, the web W also has high liquid absorbency. Therefore, even when liquid ink adheres to the roller surface 32f of the roller under resist 32 together with the solid content GR, the ink can also be cleaned with the web W made of a fiber sheet.

Further, the web W is made of a non-woven fabric. Generally, the non-woven fabric has a porous structure. Therefore, the web surface Wf is provided with a large number of irregularities, which is advantageous for stripping the solid content GR and is also advantageous for adsorbing liquid ink.

The cleaning unit 70 according to the present embodiment has a resist roller portion 30 including a resist upper roller 31 and a resist lower roller 32 whose outer peripheral surfaces are in contact with or close to each other, and is one of the rollers of the resist lower roller 32. The surface 32f is the object to be cleaned. When double-sided printing is performed, the single-sided printed sheet S is turned upside down and carried into the nip portion of the resist roller pair. Therefore, the under-resist roller 32 comes into contact with the printed surface of the sheet S, and the undried ink adheres to the surface of the under-resist roller 32. According to the present embodiment, even when the solid content GR adheres to the roller surface 32f of the roller under resist 32, the solid content GR can be reliably peeled off by the cleaning unit 70 provided with the web W. it can.

In the cleaning unit 70 according to the present embodiment, as the under-resist roller 32, the outer circumference of a roller base material made of rubber such as EPDM is coated with a tube having high water repellency made of PFA or the like, and the roller surface. 32f uses a smooth roller. Therefore, even if the solid content GR adheres to the roller surface 32f of the roller 32 under the resist, the solid content GR can be reliably peeled off by adopting the web W having the above configuration.

In the image forming apparatus 1 according to the present embodiment, since ink is used as an example of the recording material, the solid content GR formed by drying and solidifying the ink may adhere to the roller surface 32f of the roller 32 under the resist. is there. The solid content GR obtained by drying and solidifying the ink and adhering to the roller surface 32f is difficult to remove the solid content GR even if the web having a smooth surface is brought into contact with the ink. On the other hand, in the cleaning unit 70 according to the present embodiment, since the web W having the web surface Wf which is relatively rough is adopted, the solid content GR formed by drying and solidifying the ink and fixing it. Can be surely peeled off.

The image forming apparatus 1 according to the present embodiment is an image forming apparatus having a double-sided printing function and provided with a sheet inversion portion (paper inversion portion) 15. In the case of an image forming apparatus having such a double-sided printing function, the solid content GR derived from the ink used in the above image forming tends to adhere to the roller surface 32f of the roller 32 under resist. However, in the image forming apparatus 1 according to the present embodiment, by adopting the web W having the web surface Wf composed of relatively rough surfaces while having the double-sided printing function as described above, the roller under resist 32 It is possible to reliably clean the solid content GR adhering to the roller surface 32f of the above with the web W.

As described above, in the cleaning unit 70 according to the present embodiment and the image forming apparatus 1 provided with the cleaning unit 70, even if the solid content GR derived from the ink adheres to the roller surface 32f of the roller 32 under the resist, the adhesion It is possible to clean the solid content GR with the web W.

[Second Embodiment]
FIG. 13 is a diagram showing a sheet transfer unit (sheet transfer unit) 39, which is a difference from the first embodiment in the configuration of the image forming apparatus according to the second embodiment of the present invention. The image forming apparatus according to the present embodiment has the same configuration as the image forming apparatus 1 according to the first embodiment, except for the portion shown in FIG.

In the first embodiment, the resist roller unit 30 is illustrated as an example of the sheet transport unit that transports the sheet S toward the belt transport unit 40. On the other hand, in the second embodiment, as another example of the sheet transport unit, the sheet transport unit 39 including a plurality of support rollers (first to fourth support rollers 33 to 36), a feed belt 37, and a suction portion 38. An example of adopting is illustrated.

As shown in FIG. 13, the first support roller 33 and the fourth support roller 36 are arranged at intervals in the left-right direction. The first support roller 33 and the fourth support roller 36 extend in the front-rear direction (direction orthogonal to the paper surface of FIG. 13), respectively. In the present embodiment, for example, the first support roller 33 is a drive roller, and the fourth support roller 36 is a belt speed detection roller.

The second support roller 34 is arranged obliquely downward to the right with respect to the first support roller 33. The third support roller 35 is arranged below the fourth support roller 36 and on the right side with respect to the second support roller 34 at predetermined intervals.

The feed belt 37 is stretched between the four support rollers 33 to 36 without bending. The feed belt 37 is driven as shown by the arrow C as the first support roller 33 is rotationally driven. Inside the circumference of the feed belt 37, a suction portion 38 having the same configuration as the suction portion 43 according to the first embodiment is provided. Although detailed description will be omitted, the feed belt 37 is also formed with a plurality of holes penetrating in the thickness direction, and the sheet S is placed on the belt surface (outer peripheral surface) 37f of the feed belt 37 through the holes. Is sucked as shown by arrow D.

When the cleaning unit according to the present embodiment is in the cleaning position, the pressing roller 72 presses the support roller 35 with the web W and the feed belt 37 sandwiched between them. As a result, the belt surface 37f of the feed belt 37 comes into contact with the web W.

Here, in the cleaning unit according to the present embodiment, the web surface (contact surface) of the web W is a rough surface that is rougher than the belt surface 37f of the feed belt 37. In other words, also in the present embodiment, the web surface Wf is composed of a surface that is relatively rough with respect to the belt surface 37f of the feed belt 37 so that the solid content GR can be stripped off and trapped.

Also in this embodiment, even when the solid content GR derived from ink adheres (fixes) to the belt surface 37f of the feed belt 37, the web surface Wf is a relatively rough uneven surface, so that the feed belt 37 At the portion in contact with the web W, the solid content GR adhering to the belt surface 37f of the feed belt 37 can be peeled off by the web W, and the stripped solid content GR can be trapped in the recess of the web surface Wf. it can. Therefore, it is possible to prevent the solid content GR derived from the ink from remaining on the belt surface 37f of the feed belt 37, and it is possible to suppress the occurrence of defects in image stains.

[Modification example]
Although the embodiments of the present invention have been described above, the present invention is not limited to this, and for example, the following modified embodiments can be taken.

(1) In the first embodiment and the second embodiment, water-based ink is adopted as an example of the recording material, but the present invention is not limited thereto. For example, non-aqueous ink can be used as the recording material, or toner can be used. Even when toner is used as the recording material, the toner may adhere to the surface of the sheet transport member and be cooled and solidified, and the solid content may adhere to the surface of the sheet transport member. Even in such a case, the same effect as described above can be obtained by adopting the cleaning unit 70 having the configurations of the first embodiment and the second embodiment.

(2) In the first embodiment and the second embodiment, the web W is unwound from the web roll WR and wound on the web drive roller 73, but the present invention is not limited thereto. .. For example, it is possible to adopt a configuration in which a strip sheet-shaped web is brought into contact with the sheet transport member and the web is replaced at predetermined timings.

In the first embodiment and the second embodiment, the image forming apparatus 1 provided with the sheet inversion portion 15 is adopted, but in the present invention, it is also possible to adopt the image forming apparatus not provided with the sheet inversion portion. Is. Even in an image forming apparatus that does not have a sheet reversing part in this way, a configuration is adopted in which the user turns over a sheet in which an image is formed on one side and feeds it into a manual feed tray (paper feed tray) to form an image on the back side. You can also do it. Even in this case, the solid content derived from the recording material may adhere to the sheet transport member, but even in that case, the solid content adhered to the sheet transport member is surely adhered by a cleaning device such as the cleaning unit 70. Can be removed.

1 Image forming device 30 Resist roller part (sheet transport part)
32 Roller under resist (sheet transfer member)
32f Roller surface (surface of sheet transport member)
37 Feed belt (seat transport member)
37f Belt surface (surface of sheet transport member)
39 Sheet transfer unit (sheet transfer unit)
50 Image forming unit 70 Cleaning unit (sheet cleaning device)
72 Pressing roller GR solid content (solid content derived from recording material)
W web (cleaning member)
Wf web surface (contact surface)

Claims (9)

A cleaning device for cleaning the surface of a sheet transporting member that transports a sheet in an image forming apparatus that executes an image forming process using a recording material to which solid content derived from the recording material adheres.
A cleaning member capable of contacting the surface of the sheet transport member is provided.
The contact surface of the cleaning member that comes into contact with the surface of the sheet transport member is an uneven surface that is rougher than the surface of the sheet transport member.
During the cleaning, the cleaning member moves relative to the surface of the sheet transport member.
The uneven surface of the contact surface is an uneven surface capable of stripping off the solid content adhering to the surface of the sheet transport member during the relative movement.
Cleaning device. In the cleaning device according to claim 1,
The cleaning member is a cleaning device which is a fiber sheet formed by using fibers. In the cleaning device according to claim 1 or 2.
The cleaning member is a non-woven fabric, a cleaning device. In the cleaning device according to any one of claims 1 to 3.
The recording material is ink.
A cleaning device in which the solid content adheres to the surface of the sheet transport member as the ink dries and solidifies. In the cleaning device according to any one of claims 1 to 4.
The cleaning member is a band-shaped web that forms the contact surface that contacts the sheet transport member.
The cleaning device further
A pressing roller that presses the web against the sheet transport member,
A cleaning device including a feeding roller for feeding the web and a winding roller for winding the web so that a portion of the web in contact with the sheet transport member changes. An image forming unit that executes an image forming process using a recording material,
A sheet transporting unit that transports the sheet to the image forming section and includes a sheet transporting member that comes into contact with the sheet,
The cleaning device according to any one of claims 1 to 5.
An image forming apparatus. In the image forming apparatus according to claim 6,
Equipped with a pair of resist rollers that convey the sheet toward the image formation position according to the image formation timing.
An image forming apparatus in which the sheet transport member is one of the resist roller pairs. In the image forming apparatus according to claim 7,
The one roller is an image forming apparatus in which the outer peripheral side portion in the radial direction is formed of a resin material, and the surface thereof is formed by a surface smoother than the surface of the cleaning member. In the image forming apparatus according to any one of claims 6 to 8.
Further provided with a sheet reversing portion for inverting the front and back of the sheet having an image formed on one surface of the image forming portion and transporting the sheet to the sheet transporting portion.
An image forming apparatus in which the sheet conveying member is arranged at a position in contact with a sheet on which an image is formed on one surface.

Images