JP7327043B2 - Cleaning device and image forming device - Google Patents

Description

The present invention relates to a cleaning device that cleans a conveying roller that conveys a sheet, and an image forming apparatus that includes the cleaning device.

2. Description of the Related Art 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 pair of registration rollers for feeding a sheet to an image forming position is known. The pair of registration rollers each have a length corresponding to the width of the sheet, and form a nip portion through which the sheet passes. When the leading edge of the sheet comes into contact with the nip portion while the registration roller pair stops rotating, the skew of the sheet is corrected. After that, when the registration roller pair rotates, the sheet is conveyed into the nip portion, and then sent out (conveyed) in accordance with the appropriate image forming timing at the image forming position.

Patent Documents 1 and 2 disclose cleaning devices for removing paper dust adhering to the surfaces of registration rollers. In the cleaning device, a new web surface is brought into contact with the surface of the registration roller by winding the web wound in a roll shape on the winding roller, thereby removing paper dust.

JP 2004-345805 A JP-A-2006-117420

In the techniques described in Patent Documents 1 and 2, the web comes into contact with the surface of the lower registration roller of the pair of registration rollers to clean the surface. Each time the web is cleaned against the registration roller, a winding operation of the web is performed by the take-up roller so that the portion of the web that contacts the registration roller changes.

Not only paper dust but also ink and toner for image formation on the sheet may adhere to the registration roller. Such a phenomenon can occur not only in the pair of registration rollers but also in the transport rollers that transport the sheet. If paper dust, ink, or the like adheres to the surface of the conveying roller, the sheet may not be conveyed properly or the sheet may be stained with ink. When removing ink or the like adhering to the transport roller with a web, there is a problem that the ink or the like collected on the web is transferred to the surface of the transport roller again, making it impossible to properly clean the transport roller.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a cleaning device capable of appropriately cleaning the surface of a conveying roller that conveys a sheet, and an image cleaning device equipped with the same. An object of the present invention is to provide a forming device.

A cleaning device according to one aspect of the present invention is a device capable of cleaning the surface of a conveying roller that is rotatably supported by an apparatus main body of an image forming apparatus and that conveys a sheet. This cleaning device has a strip-shaped web that contacts and cleans the surface of the conveying roller, a support roller that supports the wound body of the web, and a drive input section to which a rotational driving force is input. a winding roller that winds the web while pulling it out from the supporting roller by rotation according to the rotational driving force input to the driving input portion; a pressing roller that contacts and presses the web against the transport roller; a contact/separation mechanism that moves the web to and from the transport roller by changing the position of the pressing roller with respect to the transport roller; and a control unit that controls cleaning of the transport roller. The control unit includes a conveying state determination unit that determines whether the conveying roller is in a sheet conveying state or a sheet non-conveying state; a contact/separation control unit that controls the contact/separation mechanism so that the web is pressed against the transport roller; and a rotational speed during transport of the transport roller in the transport state in a state in which the web is pressed against the transport roller. a conveying roller rotation control unit that rotates the conveying roller at a cleaning rotation speed lower than the cleaning rotation speed; a winding control unit for performing a winding operation for winding a plurality of times at predetermined time intervals within a preset cleaning time.

Further, in the cleaning device described above, the transport roller rotation control unit controls the rotation speed to be equal to or higher than a first rotation speed at which the transport roller can be rotated once during a winding standby period between each of the plurality of winding operations, and It is preferable that the cleaning rotation speed is set within a range equal to or lower than a second rotation speed that is half the transfer rotation speed.

According to this cleaning device, the pressing roller that presses the web against the transport roller is arranged between the supporting roller that supports the wound body of the web and the winding roller that winds the web while pulling it out from the supporting roller. . The position of the pressure roller with respect to the transport roller is changed by a contact/separation mechanism, and the web is separated from and contacted with the transport roller according to the change in the position of the pressure roller with respect to the transport roller. It is possible to clean the surface of the conveying roller while the web is in contact with the conveying roller by pressing the pressing roller. The cleaning of the transport rollers by the web is controlled by the controller.

The control section includes a transport state determination section, a contact/separation control section, a transport roller rotation control section, and a winding control section. Assume that the conveying state determination unit determines that the conveying roller is in a sheet non-conveying state. In this case, the contact/separation control section controls the contact/separation mechanism so that the pressing roller presses the web against the conveying roller. When the web is pressed against the transport roller, the transport roller rotation control section rotates the transport roller. By rotating the transport roller while the web is pressed, the surface of the transport roller can be cleaned by the web. At this time, the conveying roller rotation control unit rotates the conveying roller at a cleaning rotation speed lower than the conveying rotation speed of the conveying roller when the sheet is being conveyed. Thereby, the contact time of the transport roller with the web can be lengthened. Therefore, cleaning of the conveying roller by the web can be performed more effectively.

When cleaning the conveying roller with the web, the take-up control unit causes the web to be taken up a plurality of times at predetermined time intervals within a preset cleaning time according to the rotation of the take-up roller. As a result, the portion of the web that contacts the transport roller can be changed multiple times within one cleaning period. Therefore, even if ink or the like for image formation on the sheet adheres to the transport roller, the ink or the like is surely removed from the transport roller and collected on the web, and the transport roller is appropriately cleaned. be able to.

In the above cleaning device, the winding control unit performs a monitoring process of monitoring the cumulative number of times the winding operation is performed, and the total amount of the web wound on the winding roller by the multiple winding operations. an operation count setting process for setting the number of times of the winding operation within the cleaning time so that the winding amount is constant within a predetermined allowable range according to the cumulative value; and a winding process of performing the winding operation for the number of times set by the operation number setting process.

When the winding operation of the web is performed by the winding roller, a wound body of the web is formed on the winding roller. The outer diameter of the web roll formed on the take-up roller increases with each take-up operation. That is, the outer diameter of the wound body of the web formed on the winding roller increases as the cumulative number of winding operations increases. As the outer diameter of the web roll formed on the take-up roller increases, the amount of web taken up per rotation of the take-up roller increases. Therefore, when the number of winding operations within the cleaning time is set constant, the amount of web wound according to the rotation of the winding roller changes according to the accumulated value of the number of winding operations. put away.

Therefore, the winding control unit includes a monitoring process for monitoring the accumulated number of winding operations, an operation number setting process for setting the number of winding operations, and a winding operation for the number of times set by the operation number setting process. and a winding process for executing a winding operation. In the operation count setting process, the winding control unit controls the total winding amount of the web wound on the winding roller by a plurality of winding operations to be constant within a predetermined allowable range according to the cumulative value. , set the number of winding operations within the cleaning time.

In the cleaning device described above, it is preferable that the winding control section causes each of the plurality of winding operations to be performed at equal time intervals in the winding process.

In this aspect, the take-up control section causes the web take-up operation according to the rotation of the take-up roller to be performed a plurality of times at equal time intervals within the preset cleaning time. As a result, the portion of the web that contacts the transport roller can be changed multiple times at equal time intervals within one cleaning period.

In the above cleaning device, the conveying roller rotation control section continues the rotation of the conveying roller within a predetermined rotation continuation time from the end of the cleaning time. It is desirable to control the separating/contacting mechanism so that the web is separated from the conveying roller in (1).

In this aspect, after the transport roller is cleaned by the web, the web is separated from the transport roller while the transport roller continues to rotate. As a result, paper dust, ink, etc. adhering to the transport roller can be more reliably removed from the transport roller and collected on the web.

An image forming apparatus according to another aspect of the present invention includes an apparatus main body, a conveying roller that is rotatably supported by the apparatus main body and conveys a sheet, an image forming section that forms an image on the sheet, and the conveying roller. and the above cleaning device capable of cleaning.

This image forming apparatus is provided with a cleaning device capable of reliably removing paper dust, ink, and the like from the transport roller, collecting them on the web, and appropriately cleaning the transport roller. As a result, it is possible to prevent the sheet from being improperly conveyed and the sheet to be stained with ink or the like, and to form an appropriate image in the image forming apparatus.

According to the present invention, it is possible to provide a cleaning device capable of appropriately cleaning the surface of a conveying roller that conveys a sheet, and an image forming apparatus having the cleaning device.

1 is a schematic cross-sectional view showing the internal structure of an image forming apparatus according to an embodiment of the invention; FIG. FIG. 2 is a cross-sectional view of the periphery of a pair of registration rollers and a cleaning unit of the image forming apparatus, and is a cross-sectional view of a state in which the cleaning unit is arranged at a cleaning position; 3 is a perspective view of a cleaning unit; FIG. 3 is a perspective view of a cleaning unit; FIG. 3 is a perspective view of a cleaning unit; FIG. 4 is a cross-sectional view of the cleaning unit; FIG. 3 is a perspective view of a cleaning unit and a web delivery mechanism of the image forming apparatus; FIG. 2 is a perspective view showing a state in which a transport unit frame is detached from a body frame that constitutes the device body of the image forming apparatus; FIG. 4 is a perspective view of a transport unit frame; FIG. 4 is a perspective view of a transport unit frame; FIG. FIG. 4 is a perspective view of a cleaning unit rotating portion of the transport unit frame; FIG. 5 is a cross-sectional view showing how the cleaning unit is attached to the transport unit frame; FIG. 4 is a cross-sectional view showing how the cleaning unit is attached to the transport unit frame; FIG. 2 is a cross-sectional view of the periphery of a pair of registration rollers and a cleaning unit of the image forming apparatus, and is a cross-sectional view of a state in which the cleaning unit is arranged at the attachment/detachment position; FIG. 4 is a cross-sectional view of the periphery of the pair of registration rollers and the cleaning unit of the image forming apparatus, and is a cross-sectional view in which the cleaning unit is arranged at a separated position; 2 is a block diagram showing the electrical configuration of the image forming apparatus; FIG. 4 is a timing chart when cleaning the lower resist roller with the web of the cleaning unit. 4 is a diagram showing conversion rate-related information stored in a storage unit of a cleaning control unit in the control unit of the image forming apparatus; FIG. It is a figure which shows the threshold-related information memorize|stored in the memory|storage part. 7 is a graph showing the relationship between the cumulative number of solenoid actuation times and the web take-up amount for each actuation of the solenoid. It is a figure which shows the frequency|count setting information of the operation|movement memorize|stored in the memory|storage part.

A cleaning device and an image forming apparatus according to one embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic cross-sectional view showing the internal structure of an image forming apparatus 1 according to one embodiment of the invention. The image forming apparatus 1 shown in FIG. 1 is an inkjet recording apparatus that forms (records) an image on a sheet S by ejecting ink droplets. The image forming apparatus 1 includes an apparatus main body 10 , a sheet feeding section 20 , a registration roller section 30 , a belt conveying unit 40 , an image forming section 50 , a curl correction section 60 and a maintenance unit 61 .

The device main body 10 is a box-shaped housing that accommodates various devices for forming an image on the sheet S. As shown in FIG. A first conveying path 11, a second conveying path 12, and a third conveying path 13, which serve as conveying paths for the sheet S, are formed in the apparatus main body 10. As shown in FIG.

The sheet feeding unit 20 feeds the sheet S to the first conveying 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 detachable from the apparatus main body 10 and accommodates the sheets S therein. The paper feed roller 22 is arranged on the right side of the upper end of the paper feed cassette 21 . The paper feed roller 22 conveys the sheet S accommodated in the paper feed cassette 21 to the downstream side of the first conveying path 11 .

The sheet S fed to the first transport path 11 is moved by the first transport roller pair 111 provided on the first transport path 11 to the registration roller section 30 arranged at the downstream end of 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 placed on the upper surface of the paper feed tray 24 . The sheet S placed on the paper feed tray 24 is sent out toward the registration roller section 30 by the paper feed roller 23 .

The registration roller unit 30 is a device that conveys the sheet S conveyed through the first conveying path 11 or the sheet feeding roller 23 toward the conveying belt 41 of the belt conveying unit 40 in the sheet conveying direction A1. Note that the registration roller section 30 and the belt conveying unit 40 convey the sheet S at different positions. Details of the registration roller unit 30 will be described later.

The sheet S conveyed by the registration roller section 30 is conveyed in the sheet conveying direction A2 by the belt conveying unit 40 . Note that the sheet conveying directions A1 and A2 are leftward in FIG.

The belt conveying unit 40 is arranged below the image forming section 50 . The belt conveying unit 40 conveys the sheet S conveyed by the registration roller unit 30 toward the curl correcting unit 60 in the sheet conveying direction A2 so that the sheet S passes below the image forming unit 50 . The belt conveying unit 40 includes a conveying belt 41 (conveying section), 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 section 43. have

The conveying belt 41 is an endless belt that has a predetermined width in the front-rear direction and extends in the left-right direction. The conveying belt 41 is arranged to face the image forming section 50 and conveys the sheet S on the outer peripheral surface 411 in the sheet conveying direction A2. An image forming position where an image is formed on the sheet S by the image forming unit 50 is set on the revolving movement path of the conveying belt 41 .

The transport belt 41 is stretched over 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 conveying belt 41 , a suction portion 43 is arranged facing the inner peripheral surface 412 of the conveying belt 41 . The first support roller 421 is rotationally driven by a drive motor (not shown) to rotate the conveying belt 41 in a predetermined rotation 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 to face the image forming unit 50 with the conveying belt 41 interposed therebetween. The suction unit 43 causes the sheet S held on the outer circumferential surface 411 of the conveying belt 41 to generate a negative pressure between the conveying belt 41 and the conveying belt 41 , thereby bringing the sheet S into close contact with the outer circumferential surface 411 of the conveying 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 .

Between the first support roller 421 and the second support roller 422 , the belt guide member 431 guides the circular movement of the transport belt 41 interlocked with the rotation of the first support roller 421 .

The suction unit 43 generates a suction force by sucking air from the space above the conveyor belt 41 through the grooves and through holes formed in the belt guide member 431 and the suction holes of the conveyor belt 41 . Due to this suction force, an air current (suction wind) directed toward the suction section 43 is generated in the space above the conveying belt 41 . When the sheet S is conveyed onto the conveying belt 41 by the registration roller unit 30 and covers part of the outer peripheral surface 411 of the conveying belt 41 , a suction force (negative pressure) acts on the sheet S, causing the sheet S to move onto the conveying belt 41 . is in close contact with the outer peripheral surface 411 of the .

The suction housing 432 is a box-shaped housing with an upper opening, and is arranged below the conveying belt 41 so that the upper opening is covered by the belt guide member 431 . The suction housing 432 cooperates with the belt guide member 431 to define a suction space 432A.

An opening 432B is formed in the bottom wall 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 . This exhaust duct 434 is connected to an exhaust port (not shown) provided in the apparatus main body 10 .

An image forming section 50 is arranged above the belt conveying unit 40 . The image forming unit 50 forms an image by performing an image forming process on the sheet S that is conveyed in the sheet conveying direction A2 while being held on the outer peripheral surface 411 of the conveying belt 41 . In this embodiment, the image forming method of the image forming unit 50 is an inkjet type, and an image is formed on the sheet S by ejecting ink droplets.

The image forming section 50 includes line heads 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. do. The line heads 51Bk, 51C, 51M, and 51Y are arranged side by side from the upstream side toward the downstream side in the sheet conveying direction A1.

The line head 51 forms an image on the sheet S by ejecting ink droplets onto the sheet S conveyed in the sheet conveying direction A2 while being held on the outer peripheral surface 411 of the conveying belt 41 . Thus, an image is formed on the sheet S. As shown in FIG.

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

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

On the other hand, when double-sided printing is performed on the sheet S, the sheet S on which the image forming process for the first side (front side) has been completed is sent out from the second conveying path 12 to the sheet reversing section 15 . The sheet reversing section 15 is a conveying path branched in the middle of the second conveying path 12, and is a portion where the sheet S is reversed (switched back). The sheet S whose front and back sides have been reversed by the sheet reversing section 15 is delivered to the third conveying path 13 . The sheet S sent to the third conveying path 13 is reversely conveyed by the third conveying roller pair 131 provided on the third conveying path 13, and conveyed again through the registration roller section 30 in a state where the front and back are reversed. It is supplied onto the outer peripheral surface 411 of the belt 41 . The sheet S supplied onto the outer peripheral surface 411 of the conveying belt 41 in a state in which the front and back are reversed in this way is conveyed by the conveying belt 41 while being conveyed by the image forming section 50 to form the second surface opposite to the first surface. An image forming process is performed on the (back surface). The sheet S for which double-sided printing has been completed passes through the second conveying path 12 and is discharged onto the paper discharge section 14 from the paper discharge port 12A.

In the image forming apparatus 1 , ink is ejected from the line head 51 when an image forming process for forming an image on the sheet S is executed. On the other hand, when maintenance processing is performed on the line head 51 while the image forming processing on the sheet S is suspended, a purge processing for ejecting pressurized ink from the line head 51 is performed. Maintenance processing for the line head 51 is performed by the maintenance unit 61 shown in FIG. The maintenance unit 61 includes a cap unit 61B and a wipe unit 61C mounted on a carriage 61A. Details of the configuration of the maintenance unit 61 and details of the maintenance process for the line head 51 will be described later.

FIG. 2 is a cross-sectional view of the periphery of the pair of registration rollers 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 above-described registration roller section 30 has a registration housing 30H and a pair of registration rollers including an upper registration roller 31 (upper registration roller) and a lower registration roller 32 (transport roller, lower registration roller). The resist housing 30H is attached to the apparatus main body 10 and rotatably supports the upper resist roller 31 and the lower resist roller 32 . The sheet S is carried into the nip portion of the pair of registration rollers in the registration housing 30H as indicated by the arrow in FIG. The registration roller section 30 has a registration drive section 30M (see FIG. 16 described later) that drives the upper registration roller 31 and the lower registration roller 32 to rotate.

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

The lower registration roller 32 is a roller arranged on the lower side of the pair of registration rollers. The resist lower roller 32 is composed of a rubber roller, and a PFA (polytetrafluoroethylene-perfluoroalkoxyethylene copolymer resin) tube is wound (fitted) on its outer peripheral surface.

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

Furthermore, the image forming apparatus 1 includes a cleaning device 7 . The cleaning device 7 can clean the surface of the lower resist roller 32 . The cleaning device 7 has a cleaning unit 70 and a moving mechanism 75 (see FIG. 9). The moving mechanism 75 has a function of moving the cleaning unit 70 between the cleaning position (FIG. 2), the attachment/detachment position (FIG. 14), and the separation position (FIG. 15).

3 to 5 are perspective views of the cleaning unit 70 of the image forming apparatus 1 according to this embodiment. FIG. 6 is a cross-sectional view of the cleaning unit 70 at cross-sectional position II in FIG.

The cleaning unit 70 has a cleaning portion 70A and a cleaning housing 70H. The cleaning part 70A has a shape extending along the axial direction of the lower resist roller 32 and contacts the surface of the lower resist 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 (pair of walls), a connection wall 703, a pair of unit fulcrum pins 70P (housing shaft), a seat member 704, and a pair of guide rollers 705 (guides). rollers) and A front wall 701, a rear wall 702 and a connection 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 to face each other in the front-rear direction (the axial direction of the lower resist roller 32) and support the cleaning section 70A. The connection 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 and a bottom wall 703B (FIGS. 5 and 6). A pair of front and rear ribs 703T protrude from the bottom wall 703B (see FIGS. 12 and 13).

The pair of unit fulcrum pins 70P protrude in the front-rear direction from the outer side surfaces of the front wall 701 and the rear wall 702 (pair of wall portions). The unit fulcrum pin 70P is arranged at the lower left portions of the front wall 701 and the rear wall 702 . Each unit fulcrum pin 70P has a two-stage cylindrical shape with an outer diameter that decreases toward the tip.

A sheet member 704 is fixed to the bottom wall 703B so as to define the left side 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 conveying unit 40 (FIG. 1).

The pair of guide rollers 705 are respectively supported by the front wall 701 and the rear wall 702 above the unit fulcrum pin 70P, and each include an outer peripheral surface rotatable around a central axis (second central axis) parallel to the front-rear direction. . The guide rollers 705 are arranged on the upper right portions of the front wall 701 and the rear wall 702 . The pair of guide rollers 705 has a function of guiding the cleaning unit 70 when the cleaning unit 70 moves to the attachment/detachment position, the separated position and the cleaning position.

The cleaning unit 70A includes a web W, a web driven roller 71 (support roller) rotatably supported by a front wall 701 and a rear wall 702, a pressure roller 72, and a web driving roller 73 (winding roller). , (see FIG. 6). The web W is made of a belt-shaped member having a contact surface capable of coming into contact with the surface of the lower registration roller 32, and is made of a cloth material such as non-woven fabric, for example. The web W comes into contact with the surface of the lower resist roller 32 and cleans the surface. In this embodiment, as shown in FIG. 6, a web roll WR as a wound body in which the web W is pre-wound into a roll shape is fitted around the web driven roller 71 . The leading end of the web W is fixed to the outer peripheral surface of the web driving roller 73 after being put on the outer peripheral surface of the pressing roller 72 .

The web driven roller 71 is a support roller that supports the web roll WR that is the wound body of the web W. As shown in FIG. The web drive roller 73 is a take-up roller having a drive roller gear 713 as a drive input portion to which rotational driving force is input. The web driving roller 73 winds the web W while pulling it out from the web driven roller 71 by rotating according to the rotational driving force input to the driving roller gear 713 . The pressing roller 72 contacts the back surface of the web W between the web driven roller 71 and the web driving roller 73 and presses the front surface of the web W against the lower registration roller 32 . When the cleaning unit 70 is arranged at the cleaning position (FIG. 2) described above, the pressing roller 72 contacts the lower registration roller 32 with the web W therebetween. As the web W is pulled out from the web driven roller 71 according to the rotation of the web drive roller 73, the portion of the web W that contacts the lower registration roller 32 via the pressure roller 72 changes.

As shown in FIG. 5, the state of the web roll WR supported by the web driven roller 71 can be viewed from the outside of the cleaning unit 70 through an opening formed between the side wall 703A and the bottom wall 703B. can. Therefore, it is possible to prevent the cleaning unit 70 from being detached from the apparatus main body 10 during use and the amount of the web W that can be fed out to become small, from being erroneously attached to the apparatus 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 the aforementioned drive roller gear 713 (FIG. 6).

The unit input gear 711 is rotatably supported at the lower end and right end of the front wall 701 . An input gear shaft 711S of the unit input gear 711 penetrates the front wall 701 and extends inside (rear 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 driving roller gear 713, respectively. The drive roller gear 713 is a gear fixed to one end of the web drive roller 73 and functions as a drive input section to which rotational driving force for rotating the web drive roller 73 is input.

FIG. 7 is a perspective view of the cleaning unit 70 and the web delivery mechanism 81 of the image forming apparatus 1 according to this embodiment. The cleaning device 7 further includes a web delivery mechanism 81 (web drive mechanism). The web delivery mechanism 81 is attached to the apparatus main body 10 of the image forming apparatus 1 . The web delivery mechanism 81 has a function of delivering the web W of the cleaning unit 70 . The web delivery mechanism 81 is connected to the cleaning unit 70 by arranging the cleaning unit 70 at the cleaning position. The web delivery mechanism 81 has a solenoid 811 , a third detection sensor 813 (detection section), and transmission gears 814 and 815 .

A solenoid 811 generates a drive force for rotating the web drive roller 73 . The solenoid 811 has a retractable shaft 811S and rotates a rotating arm 812 (rotating member). The retractable shaft 811S retracts with respect to the main body of the solenoid 811. As shown in FIG. The rotating arm 812 is a rotating member that is rotatably supported by the apparatus main body 10 . The solenoid 811 rotates the rotating arm 812 in accordance with the retracting motion of the retracting shaft 811S by energization. output as The solenoid 811 is supported by a drive frame (not shown) made of sheet metal arranged inside the apparatus main body 10 .

The rotating arm 812 is rotatably supported by a shaft 812S (FIG. 7) provided in the drive frame inside the apparatus main body 10. As shown in FIG. 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 rightward from the rotation center axis of the rotating arm 812 . A distal end portion of the first arm portion 812A is connected to the retractable shaft 811S. The second arm portion 812B extends downward from the rotation center axis of the rotating arm 812 on the side opposite to the first arm portion 812A. A detection piece 812C is fixed to the tip (lower end) of the second arm portion 812B. Further, the rear end portion of the shaft 812S is provided with a gear portion 812T capable of integrally rotating with the shaft 812S. Further, the web delivery 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 on the shaft 812S. Also, 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 on the shaft 812S.

A 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 detection unit that detects the detection piece 812C when the detection piece 812C is arranged in a predetermined detection area according to the rotation of the rotating arm 812 .

The transmission gear 814 is rotatably supported by the device main body 10 and is engaged with the gear portion 812T. Incidentally, the transmission gear 814 consists of a two-stage gear. Similarly, the transmission gear 815 is rotatably supported by the apparatus main body 10, engages with the rear gear portion of the two-stage gear of the transmission gear 814, and engages with the aforementioned unit input gear 711. are doing.

7 shows a state in which the retractable shaft 811S is retracted (contracted) with respect to the body of the solenoid 811. FIG. When the solenoid 811 is deenergized from the state shown in FIG. 7, the retractable shaft 811S protrudes (extends) from the main body of the solenoid 811, and the rotating arm 812 rotates counterclockwise in FIG. 7 around the shaft 812S. Rotate. At this time, since the rotating arm 812 rotates relative to the shaft 812S due to the action of the first one-way clutch, the shaft 812S does not rotate. On the other hand, when the solenoid 811 is energized in order to wind the web W by a predetermined amount, the projecting/retracting shaft 811S contracts with respect to the body of the solenoid 811 . As a result, the rotating arm 812 rotates clockwise in FIG. 7 around the shaft 812S. At this time, the shaft 812S rotates integrally with the rotating arm 812 by a predetermined angle due to the action of the first one-way clutch. As a result, the rotational driving force is input to the unit input gear 711 via the transmission gears 814 and 815 from the gear portion 812T fixed to the shaft 812S. Then, the rotational driving force is further transmitted to the unit input gear 711, the interlocking gear 711T, the transmission gear 712, and the driving roller gear 713 of the cleaning unit 70, and the web driving roller 73 rotates by a preset rotation angle, and the web W moves to be taken up by the web drive roller 73 . As a result, the portion of the contact surface of the web W that faces the lower registration roller 32 changes. It should be noted that every time the rotating arm 812 rotates one reciprocating motion, the third detection sensor 813 detects the detection piece 812C, thereby detecting that the unit input gear 711 rotates and the web W moves.

When the web W moves so as to be wound around the web driving roller 73, the solenoid 811 is de-energized and the projecting/retracting shaft 811S projects again from the main body of the solenoid 811. As shown in FIG. At this time, reverse rotation of the shaft 812S is prevented by the action of the aforementioned second one-way clutch. Also, the one-way clutch provided on the drive roller shaft 73S of the web drive roller 73 functions to prevent the web drive roller 73 from rotating in the reverse direction. The projecting/retracting shaft 811S is retracted and retracted by switching the energized state of the solenoid 811 between energization and de-energization. The rotating arm 812 rotates according to the retracting operation of the retracting shaft 811S, and the web driving roller 73 rotates according to the rotation. As a result, the web W moves so as to be wound on the web drive roller 73 . Thus, in this embodiment, it is possible to send out the web W from the web roll WR supported by the web driven roller 71 by using a slight retraction stroke of the retraction shaft 811S of the solenoid 811 . In another embodiment, the web delivery mechanism 81 may rotate the web driven roller 71 in addition to the web drive roller 73 .

7, the pressure roller shaft 72S of the pressure roller 72 is provided with a torque limiter 72T. When 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 sandwiched between the upper resist roller 31 and the lower resist roller 32, the sheet S is jammed in the image forming apparatus 1. may occur. In this case, the user opens a 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. and try to remove the sheet S jammed between. At this time, when the force for pulling out the sheet S is transmitted from the lower registration roller 32 to the pressing roller 72 , the web W is excessively fed from the pressing roller 72 to the web drive roller 73 side. In the present embodiment, since the pressure roller shaft 72S is provided with the torque limiter 72T, when a sudden rotational force is applied to the pressure roller 72, the rotation of the pressure roller 72 is locked, and the web W is fed out. prevented.

A moving mechanism 75 (FIG. 2) moves the cleaning unit 70 to a cleaning position (FIG. 2), an attachment/detachment position (FIG. 14) below the cleaning position, and a separated position (FIG. 15) between the cleaning position and the attachment/detachment position. ) can be moved between The moving mechanism 75 allows the pressing roller 72 of the cleaning section 70A to contact the lower registration roller 32 via the web W at the cleaning position, and moves the cleaning section 70A downward with respect to the lower registration roller 32 at the attachment/detachment position. and allows the cleaning unit 70 to be attached to and detached from the apparatus main body 10 . Further, at the separated position, the cleaning section 70A is arranged below and spaced apart from the lower registration roller 32, and the connection between the cleaning unit 70 and the web delivery mechanism 81 is released.

The moving mechanism 75 functions as a contact/separation mechanism that changes the position of the pressing roller 72 with respect to the lower registration roller 32 by moving the cleaning unit 70 to bring the web W into contact with and separate from the lower registration roller 32 . The moving mechanism 75 moves the cleaning unit 70 to the cleaning position so that the pressing roller 72 presses the web W against the lower registration roller 32 . Further, the moving mechanism 75 moves the cleaning unit 70 to the spaced position, thereby disposing the pressing roller 72 below the lower resist roller 32 and separating the web W from the lower resist roller 32 .

FIG. 8 is a perspective view showing a state in which the conveying unit frame 40H is detached from the body frame 100 forming the device body 10 of the image forming apparatus 1 according to this embodiment. 9 and 10 are perspective views of the transport unit frame 40H.

The belt transport unit 40 shown in FIG. 1 further has a transport unit frame 40H. The transport unit frame 40H integrally includes 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, and the suction section 43. Support. The transport unit frame 40H can be attached to the body frame 100 of the apparatus body 10 along a first direction (backward direction) parallel to the front-rear direction (the axial direction of the lower registration roller 32), and can be mounted from the body frame 100 to the first direction. It is detachable along a second direction (forward direction) opposite to the first direction.

9 and 10, transport unit frame 40H includes front frame 401, rear frame 402, left frame 403, first right frame 404A (upper connection frame), and second right frame 404B (lower frame). 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 part of the transport unit frame 40H. A front cover 401A is attached to the front frame 401. As shown in FIG. The front cover 401A forms part of the front surface of the apparatus body 10. As shown in FIG. The rear frame 402 is a frame arranged on the rear surface portion of the transport unit frame 40H, and is arranged 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. Also, 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, a rectangular frame structure is formed by the first right frame 404A, the second right frame 404B, and the pair of side plates. The pair of left and right rail portions 40</b>R are rail portions for allowing the transport unit frame 40</b>H to slide in the front-rear direction with respect to the main body frame 100 . 9 and 10 show only the right rail portion 40R, 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 that are spaced apart in the front-rear direction on the upper surface of the second right frame 404B. A pair of magnets 404</b>C has a function of holding the cleaning unit 70 .

As shown in FIGS. 9 and 10, 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 unit 43, and the like are arranged in the transport unit mounting portion 40A. On the other hand, in the space between the first right frame 404A and the second right frame 404B, a cleaning unit mounting portion 40B (unit housing portion) is arranged. The cleaning unit mounting portion 40B accommodates the cleaning unit 70 described above, which is arranged at the mounting/demounting position, and allows the cleaning unit 70 to be mounted. The cleaning unit mounting portion 40B constitutes a part of the moving mechanism 75. As shown in FIG.

Further, the transport unit frame 40H has a cleaning unit rotating portion 45 and a rotating input gear 40G. FIG. 11 is a perspective view of the cleaning unit rotating portion 45 of the transport unit frame 40H according to this embodiment.

The cleaning unit rotating portion 45 is supported by the pair of side plates immediately below the first right frame 404A. 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 (fixed members), and a pair of front and rear rotating levers 454 (support members). ) and

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 in the front-rear direction (the axial direction of the lower registration roller 32 ) and forms a central axis (first central axis) for rotation of the pair of rotating levers 454 . The rotating gear 452 is a gear fixed to the rear end of the rotating shaft 451 and is engaged with the rotating input gear 40G.

A pair of front and rear rotating levers 454 are arranged in the cleaning unit mounting portion 40B, and support the cleaning housing 70H of the cleaning unit 70 so as to sandwich the cleaning housing 70H from both sides in the front-rear direction (the axial direction of the lower registration roller 32). is possible. A pair of front and rear rotating levers 454 are formed with pin receiving portions 454P (shaft support portions). The pin receiving portion 454P receives the unit fulcrum pin 70P (FIGS. 3 and 4) of the cleaning unit 70 along a direction perpendicular to the front-rear direction (the axial direction of the lower registration roller 32) and enables the unit fulcrum pin 70P to rotate. It has a supporting function. A pair of front and rear lever support portions 453 are fixed to the rotating shaft 451 so as to be able to hold a pair of rotating levers 454 respectively.

Further, the cleaning device 7 has a rotation driving portion 75K. The rotation driving section 75K constitutes a part of the moving mechanism 75. As shown in FIG. The rotation driving portion 75K moves the cleaning unit 70 between the cleaning position and the attachment/detachment position via the separated position with the pair of unit fulcrum pins 70P supported by the pair of pin receiving portions 454P. The pair of rotating levers 454 are rotated around the central axis (first central axis) of the rotating shaft 451 so as to move. Note that the central axis is arranged above the pin receiving portion 454P in FIG. In addition, the rotation driving portion 75K rotates the pair of unit fulcrum pins 70P relative to the pair of pin receiving portions 454P so that the cleaning unit 70 maintains a posture in which the cleaning portion 70A (web W) of the cleaning unit 70 faces upward. The pair of rotating levers 454 are rotated while permitting relative rotation with each other.

The rotation drive section 75K has a unit drive section 80 (FIG. 2) in addition to the cleaning unit rotation section 45 described above. The unit driving section 80 generates driving force for rotating the rotating shaft 451 of the cleaning unit rotating section 45 around its central axis. Referring to FIG. 2 , unit drive section 80 includes a motor (not shown) including drive motor output shaft 801 , pulse plate 802 , first detection sensor 803 , second detection sensor 804 , and unit drive output gear 805 . (FIG. 14).

The pulse plate 802 is fixed to the drive motor output shaft 801 and rotates together with the drive motor output shaft 801 . A first detection sensor 803 detects the amount of rotation of the pulse plate 802 . Specifically, the first detection sensor 803 has a light-emitting portion that emits detection light and a light-receiving portion that receives the detection light. A plurality of slits are formed in the pulse plate 802 at intervals along the direction of rotation thereof. As the pulse plate 802 rotates, the detected light is blocked by the slit, and the light receiving section outputs a signal corresponding to the waveform of the detected light. detected.

The second detection sensor 804 is composed of a known PI sensor and detects that the cleaning unit 70 is placed at the cleaning position shown in FIG. In this embodiment, the cleaning unit 70 is detected by the second detection sensor 804 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 driving output gear 805 transmits the rotational driving force generated by the motor of the unit driving section 80 to the rotation input gear 40G of the cleaning unit rotating section 45 . In this embodiment, when the transport unit frame 40H is attached to the main body frame 100, the rotation input gear 40G and the unit driving output gear 805 are engaged with each other to enable transmission of rotational driving force.

FIG. 12 is a sectional view showing how the cleaning unit 70 is attached to the transport unit frame 40H according to this embodiment, and FIG. 13 is a sectional view showing how the cleaning unit 70 is attached to the transport unit frame 40H. is. FIG. 14 is a cross-sectional view of the periphery of the pair of registration rollers and the cleaning unit 70 of the image forming apparatus 1, and is a cross-sectional view showing a state in which the cleaning unit 70 is arranged at the attachment/detachment position. FIG. 4 is a cross-sectional view of the periphery of the registration roller pair and the cleaning unit 70, and is a cross-sectional view in a state where the cleaning unit 70 is arranged at a separated position;

Referring to FIG. 14, 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 the rotation of the pair of rotation levers 454 about the first central axis, and moves the cleaning unit 70 between the cleaning position and the attachment/detachment position. guide 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 pair of front and rear first guide surfaces 101</b>R are formed from the left side surfaces of the pair of front and rear guide frames 101 provided on the body frame 100 . The first guide surface 101R is inclined so as to guide the cleaning unit 70 (guide roller 705) to the right as it advances upward. Similarly, the pair of front and rear second guide surfaces 102</b>R are formed by parts of a pair of front and rear registration frames provided on the 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 as it advances upward.

Further, the moving mechanism 75 has a pair of front and rear positioning portions 102S. The positioning portion 102S contacts the guide roller 705 of the cleaning unit at the cleaning position, and positions the cleaning unit 70 so that the web W of the cleaning portion 70A can clean the lower resist roller 32. FIG. As shown in FIG. 14, the positioning portion 102S is connected to the second guide surface 102R and has an arc shape along the outer peripheral surface of the guide roller 705. As shown in FIG. In addition, in FIG. 14, respective members on the rear side of the pair of front and rear first guide surfaces 101R, second guide surfaces 102R, and positioning portion 102S are shown.

As shown in FIG. 8, when the transport unit frame 40H is pulled forward from the body frame 100 of the apparatus body 10, the operator can attach the cleaning unit 70 to the cleaning unit mounting portion 40B of the transport unit frame 40H. At this time, as shown in FIG. 12, the pair of rotating levers 454 are arranged to extend downward from the rotating shaft 451 (first central shaft), and the pin receiving portion 454P is located on the right side of the rotating lever 454 (in the width direction). (one end side in the width direction) is obliquely notched toward the left side (the other end side opposite to the one end side in the width direction) and 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 portions 454P from above while gripping the side wall 703A and the bottom wall 703B (FIG. 6) of the cleaning unit 70. (Fig. 13). At this time, the aforementioned unit input gear 711 is arranged behind the unit fulcrum pin 70P on the front side of the cleaning unit 70 . Further, the unit fulcrum pin 70P on the rear side of the cleaning unit 70 is fitted into the pin receiving portion 454P.

When the pair of unit fulcrum pins 70P of the cleaning unit 70 are fitted into the pin receiving portions 454P of the pair of rotating levers 454 by an operator, the bottom wall 703B of the cleaning housing 70H is arranged to face the pair of magnets 404C. , and a pair of ribs 703T abut on the upper surface of the second right frame 404B. 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. As shown in FIG. Therefore, even if the operator lets go of the cleaning unit 70, the cleaning unit 70 is prevented from falling off the transport unit frame 40H.

As described above, when the cleaning unit 70 is attached to the cleaning unit attachment portion 40B (attachment position) of the transport unit frame 40H, the operator inserts the transport unit frame 40H into the body frame 100. FIG. As a result, the cleaning unit 70 is inserted into the body frame 100, and the rotation input gear 40G of the transport unit frame 40H is engaged with the unit drive output gear 805 of the unit drive section 80 inside the body frame 100. FIG. Also, at this time, the pair of front and rear guide rollers 705 of the cleaning unit 70 are arranged to face the first guide surfaces 101R of the pair of front and rear guide portions 100G at a predetermined interval in the left-right direction.

As shown in FIG. 14, when the cleaning unit 70 arranged at the attachment/detachment position is viewed from a direction parallel to the axial direction of the lower registration roller 32, the center (P2) of the unit fulcrum pin 70P supported by the pin receiving portion 454P is , is arranged below and to the right of the central axis (P1) of the rotating shaft 451 (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 this embodiment, the pressing roller 72 includes a heavy pressing roller shaft 72S made of metal. Therefore, the center of gravity (J) of the cleaning unit 70 is eccentric to the right side of the cleaning unit 70 so as to be located on 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 of the center (P2) of the unit fulcrum pin 70P (the leading end in the moving direction of the cleaning unit 70 in the left-right direction).

From the state shown in FIG. 14, the rotating shaft 451 of the cleaning unit rotating portion 45 is rotated by the driving force of the unit driving portion 80, and the pair of rotating levers 454 are rotated according to the rotation of the rotating shaft 451. . At this time, the left end of the bottom wall 703B moves upward as the unit fulcrum pin 70P moves. 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 by the magnet 404C is reduced, and the bottom wall 703B of the cleaning unit 70 can be easily separated from the magnet 404C. can. Thereafter, when the cleaning unit 70 tilts to the right around the unit fulcrum pin 70P due to its own weight, the pair of guide rollers 705 come into contact with the first guide surfaces 101R of the pair of guide portions 100G.

After that, when the pair of rotating levers 454 rotates further according to the rotation of the rotating shaft 451, 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 locus of rotation of the pivot lever 454 and the locus of movement of the cleaning unit 70 guided by the first guide surface 101R are different from each other. In this embodiment, a pair of unit fulcrum pins 70P of the cleaning unit 70 are supported so as to be relatively rotatable with respect to the pin receiving portion 454P of the rotating lever 454. As shown in FIG. Therefore, the attitude of the cleaning unit 70 can be changed as it moves upward, so that the cleaning unit 70 can be smoothly raised in accordance with the rotation of the rotating lever 454 .

In the state shown in FIG. 15, the pair of guide rollers 705 are transferred from the first guide surface 101R to the second guide surface 102R. Then, when the pair of rotating levers 454 rotates further in accordance with the rotation of the rotating shaft 451, the pair of guide rollers 705 is soon fitted into the pair of positioning portions 102S in contact therewith. At this time, as shown in FIG. 2, the pressure roller 72 of the cleaning section 70A of the cleaning unit 70 is moved downward to the lower registration roller 32 along a straight line L connecting the center of the upper registration roller 31T and the center of the lower registration roller 32. abut from When the cleaning unit 70 reaches the cleaning position shown in FIG. 2 in this manner, the pressing roller 72 presses the web W against the lower resist roller 32 , thereby removing paper dust, ink, etc. adhering to the surface of the lower resist roller 32 . can be cleaned. 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 the posture of the cleaning unit 70 at the cleaning position is stable. and maintained.

In the present embodiment, the first detection sensor 803 detects the amount of rotation of the pulse plate 802 with reference to the attachment/detachment position shown in FIG. A position (cleaning position, separation position) 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.

Next, the control system of the image forming apparatus 1 and the cleaning device 7 according to this embodiment will be described with reference to the block diagram of FIG. The image forming apparatus 1 further includes a control section 90 .

The control unit 90 is composed of a microcomputer having a built-in storage device such as a ROM (Read Only Memory) for storing control programs and a flash memory for temporarily storing data. The control unit 90 controls the operation of the image forming apparatus 1 including the cleaning device 7 by reading out the control program. The controller 90 includes an image formation controller 90G, a maintenance controller 90M, and a cleaning controller 90C.

The image forming control section 90G mainly controls the sheet conveying operation of the belt conveying unit 40 and the image forming operation of the image forming section 50, and executes the image forming process on the sheet S. FIG.

The maintenance control unit 90</b>M controls the purge mechanism 50</b>P and the maintenance operation mechanism 61</b>M to perform maintenance processing on the line head 51 when the image forming process on the sheet S is suspended. Maintenance processing for the line head 51 includes cap processing, purging processing, and wiping processing.

The capping process is a process of capping the line head 51 . The maintenance control unit 90M mainly controls the maintenance operation mechanism 61M to perform cap processing. The maintenance operation mechanism 61M moves the carriage 61A in the maintenance unit 61 (FIG. 1) to move the cap unit 61B to a retracted position in the horizontal direction (horizontal direction) with respect to the image forming section 50, vertically downward with respect to the maintenance position. Prior to moving the cap unit 61B from the retracted position to the maintenance position, the maintenance operation mechanism 61M lowers the belt conveying unit 40 vertically downward from the position immediately below the image forming section 50. FIG. When the cap unit 61B is placed at the maintenance position, the maintenance operating mechanism 61M vertically lifts the cap unit 61B. As a result, the cap unit 61B comes into contact with the ink ejection surface of the line head 51 and is capped.

The purge process is a process of forcibly ejecting pressurized ink from the line head 51 in order to remove air bubbles, foreign matter, thickened ink, and the like from the ink ejection nozzles of the line head 51 . The wiping process is a process of wiping off ink droplets adhering to the ink ejection surface of the line head 51 after the purge process. By moving the carriage 61A in the maintenance unit 61, the maintenance operation mechanism 61M moves the wipe unit 61C between a retracted position horizontally retracted from the image forming section 50 and a vertically downward maintenance position with respect to the image forming section 50. move between When the wipe unit 61C is moved from the retracted position to the maintenance position, the cap unit 61B supported above the wipe unit 61C in the carriage 61A remains at the retracted position. Prior to moving the wiping unit 61C from the retracted position to the maintenance position, the maintenance operation mechanism 61M lowers the belt conveying unit 40 vertically downward from the position immediately below the image forming section 50 . When the wipe unit 61C is placed at the maintenance position, the maintenance operating mechanism 61M vertically raises the wipe unit 61C. After that, the maintenance control section 90M executes a purge process for the line head 51 by controlling the purge mechanism 50P, and moves the blade unit of the wipe unit 61C by controlling the maintenance operation mechanism 61M. Execute the wiping process.

The cleaning control section 90</b>C constitutes a part of the cleaning device 7 and controls cleaning of the lower resist roller 32 by the cleaning unit 70 using the web W. In the present embodiment, the cleaning control unit 90</b>C performs a double-sided image forming process on both the first surface (front surface) and the second surface (back surface) of the sheet S conveyed by the registration roller unit 30 . cleaning of the lower resist roller 32 by the cleaning unit 70 is controlled based on the number of conveyed sheets S in the above. The cleaning control unit 90</b>C controls cleaning of the lower registration roller 32 by the cleaning unit 70 when the image forming process for the sheet S is suspended and the lower registration roller 32 is in the non-conveying state of the sheet S.

The sheet S on which an image has been formed on the first side in the double-sided image forming process (double-sided printing) passes through the sheet reversing section 15 and the third conveying path 13 as described above, and is again turned upside down and sent to the registration roller section. 30 is brought in. At this time, if the ink of the image formed on the first surface adheres to the surface of the PFA tube of the lower resist roller 32, the ink adheres to the leading edge of the next sheet S from the lower resist roller 32, causing sheet contamination. . Further, when the ink adhering to the lower resist roller 32 is transferred to the upper resist roller 31, the ink adheres to the first surface of the next sheet S, thereby causing an image defect.

Therefore, in the present embodiment, the cleaning control section 90C arranges the cleaning unit 70 at the cleaning position within a preset cleaning time CLT (FIG. 17) corresponding to execution of double-sided printing, while the cleaning unit 70 is placed at the cleaning position during single-sided printing. 70 is placed in the spaced position. That is, the cleaning control section 90C arranges the cleaning unit 70 at the cleaning position during the cleaning time CLT, and arranges the cleaning unit 70 at the separated position during other time periods. As a result, it is possible to clean the lower registration roller 32 over a long period of time even with the limited length of the web roll WR, and it is possible to make the web roll WR compact and to reduce the size of the cleaning device 7. becomes.

Further, when an image is formed under conditions where the surface of the lower registration roller 32 is less likely to become dirty, such as during single-sided printing, the cleaning unit 70 is arranged at the separated position so that the cleaning section 70A can be applied to the lower registration roller 32. It is possible to reduce the load on the lower registration roller 32 due to the contact and to suppress unnecessary feeding out of the web W.

The control of the cleaning control section 90C will be described with reference to FIGS. 17 to 21 in addition to FIG. FIG. 17 is a timing chart when cleaning the lower registration roller 32 with the web W of the cleaning unit 70 . FIG. 18 is a diagram showing the conversion rate related information J1 stored in the storage unit 99 of the cleaning control unit 90C. FIG. 19 is a diagram showing the threshold-related information J2 stored in the storage unit 99. As shown in FIG. FIG. 20 is a graph showing the relationship between the cumulative number of times the solenoid 811 is actuated and the amount of web taken up each time the solenoid 811 is actuated. FIG. 21 is a diagram showing the number-of-operations setting information J3 stored in the storage unit 99. As shown in FIG.

As shown in FIG. 16, the cleaning control unit 90C includes a conveying number determining unit 91, a conveying state determining unit 92, a contact/separation control unit 93, a registration rotation control unit 94 (conveying roller rotation control unit), and a winding unit. It includes a control unit 95 , an operation count determination unit 96 , a web end determination unit 97 , an information generation unit 98 and a storage unit 99 .

The storage unit 99 stores information referred to when controlling the cleaning of the lower registration roller 32 by the web W of the cleaning unit 70 . The storage unit 99 stores conversion rate related information J1 shown in FIG. 18, threshold related information J2 shown in FIG. 19, and operation frequency setting information J3 shown in FIG.

The conversion rate related information J1 shown in FIG. 18 is information indicating a conversion rate for each size of the sheet S for converting the size of the sheet S into the number of conveyed sheets S, and the sheet size information J11 and the conversion rate information J12 are combined. associated information.

The sheet size information J11 is information indicating the size of the sheet S. FIG. The size of the sheet S is represented by, for example, "A4 size" or "A3 size". The conversion rate information J<b>12 is information indicating a conversion rate regarding the number of sheets S conveyed by the registration roller unit 30 . The conversion rate registered in the conversion rate information J12 is set to a larger value as the size of the sheet S registered in the sheet size information J11 increases. For example, regarding the sizes "SS1" and "SS2" of the sheet S registered in the sheet size information J11, it is assumed that "SS1" indicates "A4 size" and "SS2" indicates "A3 size". In this case, regarding the conversion rates "CR1" and "CR2" registered in the conversion rate information J12, "CR2" associated with "SS2" indicates a larger value than "CR1" associated with "SS1". . For example, if the conversion rate "CR1" is "1", the conversion rate "CR2" is "2". In this case, when one "A4 size" sheet S is conveyed by the registration roller unit 30, the conveyed number is corrected as "1". On the other hand, when one "A3 size" sheet S is transported by the registration roller unit 30, the number of transports is corrected as "2". The conversion rate-related information J1 is referred to by the transport number determination unit 91, which will be described later.

Threshold-related information J<b>2 illustrated in FIG. 19 is information indicating a transport determination threshold that the transport number determining unit 91 refers to when determining the number of sheets S transported by the registration roller unit 30 . The threshold-related information J2 is associated with timing condition information J21, printing condition information J22, and conveyance determination threshold information J23.

The timing condition information J<b>21 is information indicating timing conditions for moving the cleaning unit 70 from the separated position to the cleaning position by the driving force of the unit driving section 80 . As described above, the cleaning control unit 90</b>C causes the cleaning unit 70 to clean the lower registration roller 32 when the image forming process on the sheet S is suspended and the sheet S is not being conveyed by the lower registration roller 32 . to control. Therefore, the movement timing of the cleaning unit 70 registered in the timing condition information J21 is the first timing or the second timing that satisfies the condition that the sheet S is not conveyed by the lower registration roller 32 . The first timing is set within a period from the end of a series of image forming processes for continuous sheets S to the start of the next image forming process. The second timing is set within a period during which the maintenance control unit 90M performs the maintenance process on the line head 51 when the image forming process on the sheet S is suspended. In the example shown in FIG. 19, the information indicating the first timing is registered as "CT1" and the information indicating the second timing is registered as "CT2" in the timing condition information J21.

The printing condition information J22 is information indicating the printing conditions of the image on the sheet S, and is information indicating, for example, the printing ratio. The printing condition information J22 is registered for each movement timing of the cleaning unit 70 indicated by the timing condition information J21. In the example shown in FIG. 19, "CP1", "CP2", etc. are registered as the printing condition information J22 corresponding to "CT1" and "CT2" of the timing condition information J21.

The transport determination threshold information J23 is information indicating a transport determination threshold that the transport number determination unit 91 refers to when determining the transport number of the sheets S transported by the registration roller unit 30 . In the example shown in FIG. 19, "TT11" and "TT12" are registered as the conveyance determination threshold information J23 for each of "CP1" and "CP2" of the printing condition information J22 corresponding to "CT1" of the timing condition information J21. "TT21" and "TT22" are registered as the conveyance determination threshold value information J23 for each of "CP1" and "CP2" of the printing condition information J22 corresponding to "CT2" of the timing condition information J21. The transport determination threshold value registered in the transport determination threshold information J23 is set to a different value according to the movement timing of the cleaning unit 70 registered in the timing condition information J21. For example, the transport determination thresholds "TT11" and "TT21" registered in the transport determination threshold information J23 are compared. In this case, the transport determination threshold "TT1" associated with "CT1" indicating the first timing in the timing condition information J21 is the transport determination threshold associated with "CT2" indicating the second timing in the timing condition information J21. It is set to a value smaller than "TT21". Also, the transport determination threshold value registered in the transport determination threshold information J23 is set to a smaller value as the printing ratio registered in the printing condition information J22 increases.

The number-of-operations setting information J3 shown in FIG. 21 is information indicating the number-of-operations-of-solenoid set value that is referenced when the winding control unit 95, which will be described later, sets the number of winding operations of the web W by the web drive roller 73. . The number of winding operations of the web W by the web driving roller 73 is the same as the number of times the solenoid 811 is operated. The operating frequency setting information J3 is associated with cumulative value information J31 and operating frequency setting value information J32.

The cumulative value information J31 is information indicating the cumulative number of operations of the web W winding operation by the web drive roller 73, that is, the cumulative number of operations of the solenoid 811. FIG. The operation frequency set value information J32 is the set value of the number of times the web driving roller 73 winds up the web W within a preset cleaning time CLT (FIG. 17), that is, the operation of the solenoid 811 in one cleaning. This is information indicating the set value of the number of times. The set value for the number of times of solenoid actuation registered in the set value information for actuation times J32 is set to a smaller value as the cumulative value of the number of times of actuation of the solenoid 811 registered in the cumulative value information J31 increases.

The conveying number determination unit 91 monitors the conveying number of the sheets S for double-sided image formation among the sheets S conveyed by the registration roller unit 30 with the cleaning unit 70 arranged at the separated position. Then, the conveying number determination unit 91 refers to the threshold related information J2 stored in the storage unit 99, and the accumulated value of the conveying number of the sheets S for double-sided image formation reaches the conveying determination threshold indicated by the conveying determination threshold information J23. Determine whether or not it has reached. At this time, the conveying number determination unit 91 refers to the conversion rate related information J1 stored in the storage unit 99, and based on the conversion rate indicated by the conversion rate information J12 corresponding to the size of the sheet S for double-sided image formation. , to correct the number of transports. Then, the transport number determination unit 91 determines whether or not the corrected cumulative number of transports reaches the transport determination threshold.

The transport state determination unit 92 determines whether or not the conditions defining the first timing and the second timing indicated by the timing condition information J21 of the threshold related information J2 stored in the storage unit 99 are satisfied. Accordingly, the transport state determination unit 92 determines whether the lower registration roller 32 of the registration roller unit 30 is in the sheet S transport state or the non-transport state. The conveying state determination unit 92 determines that if the period is from the end of a series of image forming processes on the continuous sheet S to the start of the next image forming process, which is the condition that defines the first timing, the registration It is determined that the lower roller 32 is in the non-conveying state. Further, the conveying state determination unit 92 determines that the lower resist roller 32 is in the non-conveying state during the period in which the maintenance processing for the line head 51 is performed by the maintenance control unit 90M, which is the condition that defines the second timing. I judge.

The contact/separation control section 93 controls the unit driving section 80 to move the cleaning unit 70 . The conveyance number determination unit 91 determines that the cumulative number of conveyances of the sheets S for double-sided image formation has reached the conveyance determination threshold, and the conveyance state determination unit 92 determines that the lower resist roller 32 is in the non-conveyance state. Assume that the judgment is made. In this case, the separation/contact control section 93 controls the unit drive section 80 to move the cleaning unit 70 from the separated position to the cleaning position so that the pressing roller 72 presses the web W against the lower registration roller 32 . When the cleaning unit 70 is positioned at the cleaning position by driving the unit driving section 80 , the second detection sensor 804 detects the cleaning unit 70 . When a predetermined first time t1 has passed since the cleaning unit 70 was detected by the second detection sensor 804, the contact/separation control section 93 stops driving the unit driving section 80 (see FIG. 17). The first time t1 is set to 400 ms, for example.

The registration rotation control section 94 controls the registration drive section 30M to rotate the upper registration roller 31 and the lower registration roller 32 while the web W is pressed against the lower registration roller 32 in the cleaning unit 70 arranged at the cleaning position. Let The registration rotation control section 94 drives the registration driving section 30M after a predetermined second time t2 has passed since the unit driving section 80 stopped driving (see FIG. 17). The second time t2 is set to 100 ms, for example. The surface of the lower registration roller 32 can be cleaned by the web W by rotating the lower registration roller 32 while the web W is being pressed.

In the present embodiment, the registration rotation control unit 94 controls the registration driving unit 30M, and rotates the lower registration roller 32 at a lower cleaning rotation speed than the rotation speed during transportation of the sheet S in the transportation state of the lower registration roller 32. rotate. Although the details will be described later, the winding operation of the web W by the web drive roller 73 based on the actuation of the solenoid 811 is performed multiple times at predetermined time intervals within the predetermined cleaning time CLT (see FIG. 17). The registration rotation control unit 94 controls a first rotation speed or higher at which the lower registration roller 32 can make one rotation in the winding standby period WP between each of the winding operations, and the transportation rotation speed. The cleaning rotation speed is set in a range equal to or lower than half the second rotation speed. The contact time of the lower registration roller 32 with the web W is lengthened by setting the rotation speed of the lower registration roller 32 in a state where the web W is pressed to a cleaning rotation speed lower than the rotation speed during transportation. can be done. As a result, cleaning of the lower registration roller 32 by the web W can be performed more effectively.

The take-up control unit 95 controls switching between energization and deenergization of the solenoid 811 while the lower registration roller 32 is rotating. By controlling the switching of the energized state of the solenoid 811 in this manner, the winding control unit 95 causes the web drive roller 73 to perform the winding operation of the web W a plurality of times at predetermined time intervals within the predetermined cleaning time CLT. . The take-up control unit 95 controls switching of the energized state of the solenoid 811 after a predetermined third time t3 has elapsed from the start of driving of the registration driving unit 30M (see FIG. 17). The third time t3 is set to 1000 ms, for example. Further, the cleaning time CLT is set within a range of 10 to 30 seconds, for example, based on the printing rate of the image formed on the sheet S when the image forming section 50 executes the image forming process.

Further, when the cleaning unit 70 is arranged at the cleaning position, the pressing roller 72 presses against the lower registration roller 32 to form a web pressing nip portion. The nip width of this web pressing nip portion is set, for example, within a range of 2.5 mm to 5.0 mm. The winding control unit 95 adjusts the total winding amount of the web W wound around the web driving roller 73 by a plurality of winding operations within the cleaning time CLT so as to match the nip width of the web pressing nip portion. set to

When cleaning the lower registration roller 32 with the web W, the winding control unit 95 performs the winding operation of the web W according to the rotation of the web drive roller 73 multiple times at predetermined time intervals within the cleaning time CLT. Let As a result, the portion of the web W that contacts the lower resist roller 32 can be changed multiple times within one cleaning time CLT. Therefore, even if ink or the like for image formation on the sheet S adheres to the lower resist roller 32, the ink or the like is surely removed from the lower resist roller 32, collected on the web W, and the resist is collected. The lower roller 32 can be properly cleaned.

When the web driving roller 73 winds up the web W by operating the solenoid 811 , a wound body of the web W is formed on the web driving roller 73 . The outer diameter of the wound body of the web W formed on the web drive roller 73 increases each time the web drive roller 73 winds up in response to the operation of the solenoid 811 . That is, the outer diameter of the wound body of the web W formed on the web drive roller 73 increases as the cumulative number of times the solenoid 811 operates corresponding to the number of times the web drive roller 73 performs the winding operation increases. Become. As the outer diameter of the wound body of the web W formed on the web driving roller 73 increases, the amount of the web W wound on the web driving roller 73 by one operation of the solenoid 811 increases. (See FIG. 20). Therefore, when the number of winding operations of the web drive roller 73 within the cleaning time CLT, that is, the number of times the solenoid 811 is operated is set constant, the winding amount of the web W corresponding to the rotation of the web drive roller 73 is However, it changes according to the cumulative value of the number of times the solenoid 811 is operated.

Therefore, the winding control unit 95 is configured to be able to execute monitoring processing, operation count setting processing, and winding processing. In the monitoring process, the take-up control unit 95 monitors the number of times the web drive roller 73 takes up the web W by monitoring the cumulative number of times the solenoid 811 has been operated. Further, in the operation number setting process, the winding control unit 95 sets the number of times the web drive roller 73 performs the winding operation of the web W within the cleaning time CLT, that is, the number of times the solenoid 811 operates in one cleaning. do. The winding control unit 95 refers to the operation count setting information J3 stored in the storage unit 99, and determines the total winding of the web W wound around the web driving roller 73 by a plurality of winding operations within the cleaning time CLT. The number of times the solenoid 811 is actuated in one cleaning is set so that the amount taken is constant within a predetermined allowable range according to the accumulated value of the number of times the solenoid 811 is actuated. In the winding process, the winding control unit 95 causes the solenoid 811 to operate the number of times set in the operation number setting process at predetermined time intervals within the cleaning time CLT.

In the winding process, the winding control unit 95 causes the web drive roller 73 to perform a plurality of winding operations of the web W based on the operation of the solenoid 811 at equal time intervals. As a result, the portion of the web W that contacts the lower resist roller 32 can be changed multiple times at equal time intervals within one cleaning time CLT.

When the cleaning of the lower registration roller 32 by the web W within the cleaning time CLT is completed, the registration rotation control unit 94 rotates the lower registration roller 32 within a predetermined rotation duration RCT from the end of the cleaning time CLT. is continued (see FIG. 17). Then, the separation/contact control section 93 controls the unit driving section 80 to move the cleaning unit 70 from the cleaning position to the separation position so that the web W is separated from the lower registration roller 32 within the rotation duration RCT. .

When the cleaning unit 70 is moved from the cleaning position to the separated position by driving the unit driving section 80, the detection of the cleaning unit 70 by the second detection sensor 804 is cancelled. After a predetermined fourth time t4 has elapsed since the detection of the cleaning unit 70 by the second detection sensor 804 was canceled, the registration rotation control section 94 stops driving the registration driving section 30M (see FIG. 17). The fourth time t4 is set to 500 ms, for example. Note that when the cleaning unit is arranged at the separated position, the contact/separation control section 93 stops driving the unit driving section 80 .

As described above, after the web W cleans the lower registration roller 32 , the web W is separated from the lower registration roller 32 while the lower registration roller 32 continues to rotate. As a result, paper dust, ink, and the like adhering to the lower resist roller 32 can be more reliably removed from the lower resist roller 32 and collected onto the web W.

The number-of-operations determining unit 96 monitors the number of times of operation corresponding to the energization of the solenoid 811, and determines whether or not the cumulative value of the number of times of operation has reached a predetermined threshold value for determination of operation. The actuation determination threshold value indicates that the remaining amount of the web roll WR supported by the web driven roller 71 has reached a predetermined warning amount due to the winding operation of the web W by the web drive roller 73 based on the actuation of the solenoid 811. Set to a recognizable value. For example, assume that the total length of the web roll WR is "5 m" and the average value of the amount of the web W wound by the web drive roller 73 based on one actuation of the solenoid 811 is "3.75 mm". In this case, theoretically, the trailing edge of the web W will be exposed on the web driven roller 71 when the accumulated value of the number of times the solenoid 811 is operated reaches "1333". Actually, however, as shown in FIG. 20, as the cumulative number of times the solenoid 811 is operated increases, the amount of the web W wound around the web driving roller 73 by one actuation of the solenoid 811 increases. The winding amount of the web W changes. Therefore, theoretically, "1300", which is smaller than the accumulated value "1333" of the number of times of actuation of the solenoid 811, which is estimated to expose the trailing end of the web W on the web driven roller 71, is equal to "1300". It is set as a judgment threshold.

The web end determination unit 97 performs web end determination processing for determining whether or not the end of the web W is exposed on the web driven roller 71 when the cumulative value of the number of times the solenoid 811 is operated reaches the operation determination threshold value. Execute. The web end determination section 97 determines whether or not the end of the web W is exposed on the web driven roller 71 based on the energized state of the solenoid 811 and the detection result of the third detection sensor 813 . The web end determination unit 97 detects that the end of the web W is exposed on the web driven roller 71 when the detection result of the third detection sensor 813 does not change even though the solenoid 811 is energized. I judge that. As a result, the trailing edge of the web W is exposed on the web driven roller 71, and it can be accurately determined that the web W needs to be replaced, that is, that the cleaning unit 70 needs to be replaced. Therefore, when the cleaning unit 70 is replaced, the entire web W of the web roll WR supported by the web driven roller 71 can be used up without leaving the web W in vain.

The information generation section 98 generates information indicating the determination results of the operation count determination section 96 and the web end determination section 97 . Assume that the actuation count determination unit 96 determines that the accumulated value of the actuation count of the solenoid 811 has reached the actuation determination threshold value. In this case, the information generator 98 generates remaining web warning information for notifying that the remaining amount of the web roll WR supported by the web driven roller 71 has reached a predetermined warning remaining amount. The web remaining amount warning information is, for example, message information such as "The remaining amount of the web roll WR is running low." On the other hand, it is assumed that the web end determination unit 97 determines that the end of the web W is exposed on the web driven roller 71 . In this case, the information generator 98 generates web replacement request information for notifying that the web W needs to be replaced, that is, the cleaning unit 70 needs to be replaced. The web replacement request information is, for example, message information such as "The web roll WR has been completely unwound. Please replace the cleaning unit 70."

The web remaining amount warning information and the web replacement request information generated by the information generation unit 98 are output to the notification unit DP ( FIG. 16 ) provided in the image forming apparatus 1 . The reporting unit DP reports the remaining web warning information and the web replacement request information output from the information generating unit 98 . The operator can recognize that the remaining amount of the web roll WR is low by recognizing the remaining amount warning information of the web notified by the notification unit DP. Also, the operator can recognize that the cleaning unit 70 needs to be replaced by recognizing the web replacement request information notified by the notification unit DP.

When the operator who has recognized the web replacement request information instructs the operation unit (not shown) of the image forming apparatus 1 to replace the cleaning unit 70, the contact/separation control unit 93 controls the unit drive unit 80 to replace the cleaning unit. 70 is moved 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 attaches a new cleaning unit 70 to the transport unit frame 40H. cleaning unit mounting portion 40B.

In the present embodiment, when the cleaning unit 70 is detached from the apparatus main body 10 integrally with the transport unit frame 40H, a part of the drive transmission system between the rotary drive section 75K and the pair of rotary levers 454 (device 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 are rotatable 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 out of the cleaning unit mounting portion 40B. In other words, the pair of rotating levers 454 rotates around the rotating shaft 451 so as to assist the pair of unit fulcrum pins 70P of the cleaning unit 70 to be separated from the pair of pin receiving portions 454P. As a result, the operator can easily remove 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 40</b>H of the belt transport unit 40 .

The cleaning device 7 and the image forming apparatus 1 including the same according to one embodiment of the present invention have been described above. According to such a configuration, it is possible to reliably remove paper dust, ink, and the like from the lower resist roller 32 and collect them on the web W, thereby properly cleaning the lower resist roller 32 . Therefore, the image forming apparatus 1 can form an appropriate image by suppressing the sheet S from being improperly conveyed and the sheet S being stained with ink or the like. It should be noted that the present invention is not limited to the above-described embodiments, and it is possible to adopt the following modified embodiments.

In the above-described embodiment, the position of the pressing roller 72 with respect to the lower registration roller 32 is changed as the cleaning unit 70 moves, thereby causing the web W to contact and separate from the lower registration roller 32 . It is not limited to such a mode. For example, the press roller 72 may be provided to be vertically movable, and the web W may be separated from and contacted to the lower resist roller 32 by moving the press roller 72 .

Further, in the above embodiment, the lower resist roller 32 is used as the transport roller to be cleaned by the cleaning unit 70, but the transport roller may be another roller that transports the sheet S. FIG.

Further, in the above-described embodiment, the image forming unit 50 has been described as being of the ink jet method, but the image forming unit 50 may be of another image forming method such as a known electrophotographic method.

1 Image Forming Apparatus 10 Apparatus Main Body 20 Paper Feed Section 30 Registration Roller Section 31 Upper Registration Roller (Upper Registration Roller)
32 Lower registration roller (transport roller, lower registration roller)
40 belt conveying unit 50 image forming unit 60 curl correcting unit 61 maintenance unit 7 cleaning device 70 cleaning unit 71 web driven roller (support roller)
713 drive roller gear (drive input)
72 pressure roller 73 web drive roller (take-up roller)
75 moving mechanism (separating and contacting mechanism)
80 unit driving section 81 web delivery mechanism 811 solenoid 812 rotating arm (rotating member)
812A first arm portion 812B second arm portion 812C detection piece 813 third detection sensor (detection portion)
90 control section 91 transport number determination section 92 transport state determination section 93 contact/separation control section 94 registration rotation control section (transport roller rotation control section)
95 winding control section 96 number of times of operation determination section 97 web end determination section 98 information generation section 99 storage section W web WR web roll (wound body)

Claims (6)

A cleaning device capable of cleaning the surface of a conveying roller that is rotatably supported by an apparatus body of an image forming apparatus and conveys a sheet,
a strip-shaped web that contacts the surface of the transport roller and cleans the surface;
a support roller for supporting the roll of the web;
a winding roller having a drive input section to which a rotational driving force is input, and winding the web while pulling it out from the support roller by rotation according to the rotational driving force input to the drive input section;
a pressing roller that contacts the web between the support roller and the take-up roller and presses the web against the transport roller;
a contact/separation mechanism for separating and contacting the web with respect to the transport roller by changing the position of the pressing roller with respect to the transport roller;
a control unit that controls cleaning of the transport roller by the web,
The control unit
a conveying state determination unit that determines whether the conveying roller is in a sheet conveying state or a sheet non-conveying state;
a contact/separation control unit that controls the contact/separation mechanism so that the pressing roller presses the web against the conveying roller when the conveying roller is in the non-conveying state;
a conveying roller rotation control unit that rotates the conveying roller at a lower cleaning rotation speed than the conveying rotation speed of the conveying roller in the conveying state when the web is pressed against the conveying roller;
In a state in which the transport roller is rotating at the cleaning rotation speed, a winding operation of winding the web in accordance with the rotation of the winding roller is repeated a plurality of times at predetermined time intervals within a preset cleaning time. and a winding control to run. The conveying roller rotation control unit controls a rotation speed equal to or higher than a first rotation speed at which the conveying roller can be rotated once during a winding standby period between each of the plurality of winding operations, and half the conveying rotation speed. 2. The cleaning device according to claim 1, wherein said cleaning rotation speed is set in a range equal to or lower than said second rotation speed. The winding control unit is
a monitoring process for monitoring an accumulated value of the number of operations of the winding operation;
During the cleaning time, the total winding amount of the web wound on the winding roller by the multiple winding operations is constant within a predetermined allowable range according to the cumulative value. an operation count setting process for setting the number of winding operations;
3. The cleaning device according to claim 1, capable of executing a winding process of performing the winding operation for the number of times set by the operation number setting process within the cleaning time. 4. The cleaning device according to claim 3, wherein in the winding process, the winding control section causes each of the plurality of winding operations to be performed at equal time intervals. The conveying roller rotation control unit continues the rotation of the conveying roller within a predetermined rotation continuation time from the end of the cleaning time,
The cleaning device according to any one of claims 1 to 4, wherein the contact/separation control section controls the contact/separation mechanism so that the web is separated from the conveying roller within the duration of rotation. a device body;
a conveying roller that is rotatably supported by the apparatus main body and conveys the sheet;
an image forming unit that forms an image on the sheet;
and the cleaning device according to any one of claims 1 to 5, which is capable of cleaning the transport roller.

Images