JP6597256B2 - Conveying apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a conveyance device and an image forming apparatus.

  Patent Document 1 proposes a fixing device in which a pressure belt and a fixing belt are opposed to each other, and a recording medium is held and conveyed by the pressure belt and the fixing belt. Specifically, in Patent Document 1, when it is detected that the pressure belt has moved to the outside in the width direction from the predetermined range, the pressure belt is moved back to the predetermined range by the roll and fixed by the roll. It has been proposed to move the belt in the same direction as the pressure belt.

Japanese Patent No. 5014031

  The amount of movement of the belt with respect to the amount of adjustment of the roll when moving in the direction of returning the belt position due to changes over time such as wear of the belt may change, resulting in poor adjustment. Further, when the belt is moved in a configuration in which the pair of belts are opposed to each other, the adjustment of each of the pair of belts affects each other and is difficult to adjust.

  In the present invention, the width of each of the pair of opposed belts is compared to the case where the same value is always used as the movement distance in the width direction of the belt per unit movement distance in the belt conveyance direction when adjusting the position in the width direction of the belt. It aims at improving the adjustment accuracy of a direction position.

The conveyance device according to claim 1, wherein a detection unit that detects a position in a width direction of each of a pair of belts provided to face each other for conveying a medium, and an adjustment that adjusts the position in the width direction of each of the belts. And the detection result of the detection unit, and the belt width direction movement distance per unit movement distance in the belt conveyance direction when the belt width direction position is adjusted by the adjustment unit. A control unit that controls the adjustment unit so that the position of the belt becomes a predetermined position, and the adjustment unit is controlled so that one belt is fixed at a predetermined timing and the other belt has a predetermined adjustment amount. And a correction unit that corrects the width direction movement distance used in the control unit to the width direction movement distance after the change using the detection result of the detection unit.

  The invention according to claim 2 is the notifying unit for notifying the life of the belt in the invention according to claim 1, when the movement distance in the width direction corrected by the correcting unit satisfies a predetermined life condition. Is further provided.

According to a third aspect of the present invention, in the invention of the second aspect, each adjustment amount when the correction unit controls the adjustment unit so as to have a plurality of types of adjustment amounts as the predetermined adjustment amount. The width direction moving distance used in the control unit corresponding to each of the plurality of types of adjustment amounts corresponds to each of the plurality of types of adjustment amounts after change over time using the detection result of the detection unit corresponding to the corrected in a width direction movement distance, the notification unit, the crosswise movement distance corresponding to each of the plurality of types of adjustment amount corrected by the correction unit, when the predetermined lifetime condition is satisfied, Inform the belt life.

  An image forming apparatus according to a fourth aspect includes the transport device according to any one of the first to third aspects, and an image forming unit that forms an image on a medium transported by the transport device.

  According to the first aspect of the present invention, as opposed to the case where the same value is always used as the movement distance in the width direction of the belt per unit movement distance in the belt conveyance direction when adjusting the position in the width direction of the belt, the opposing positions are opposed. A conveyance device capable of improving the adjustment accuracy of the position in the width direction of each of the pair of belts can be provided.

  According to the second aspect of the present invention, replacement or cleaning of the belt can be promoted as a life.

  According to the invention described in claim 3, in the configuration in which the pair of belts face each other as compared with the case where the life of the belt is determined using the movement distance in the width direction when the belt position is adjusted with a single adjustment amount. When adjusting the position of the belt, the life can be determined with high definition even if the influence of the other belt occurs.

  According to the fourth aspect of the present invention, as opposed to the case where the same value is always used as the movement distance in the width direction of the belt per unit movement distance in the belt conveyance direction when adjusting the position in the width direction of the belt. It is possible to provide an image forming apparatus capable of improving the adjustment accuracy of the position in the width direction of each of the pair of belts.

1 is a diagram illustrating a schematic configuration of an image forming apparatus according to an exemplary embodiment. It is a figure which shows the structure of the steering roll part of a cooling unit. (A) is a diagram showing a case where the belt (absorption belt and pressing belt) is in a normal position, (B) is a diagram showing a case where the position in the width direction of the belt is deviated from the center to one outside, (C) is a figure which shows the case where the position of the width direction of a belt has deviated from the center to the other outer side. FIG. 2 is a block diagram illustrating a configuration of a control system of the image forming apparatus according to the present embodiment. 6 is a flowchart illustrating an example of a flow of processing performed by the control device of the image forming apparatus according to the present exemplary embodiment. (A) is a figure which shows the case where the life in the belt life determination using a plurality of walk rates is not reached, (B) is the case where the life in the belt life determination using a plurality of walk rates is reached. FIG.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of an image forming apparatus 10 according to an embodiment of the present invention.

  (overall structure)

  The image forming apparatus 10 according to the present embodiment forms a full-color image or a black-and-white image. As shown in FIG. 1, a first processing unit that constitutes a horizontal one side (left side in FIG. 1) A first housing 10A accommodated, and a second housing 10B that is detachably connected to the first housing 10A and that accommodates a second processing unit constituting the other side in the horizontal direction (right side in FIG. 1). It has.

  An image signal processing unit 13 that performs image processing on image data sent from an external device such as a computer is provided on the second housing 10B.

  On the other hand, the first special color (V), second special color (W), yellow (Y), magenta (M), cyan (C), and black (K) toners are provided on the upper portion of the first housing 10A. Toner cartridges 14V, 14W, 14Y, 14M, 14C, and 14K are provided so as to be replaceable along the horizontal direction.

  The first special color and the second special color are appropriately selected from colors other than yellow, magenta, cyan, and black (including transparency). In the following description, the first special color (V), the second special color (W), yellow (Y), magenta (M), cyan (C), and black (K) are distinguished for each component. Is described with a letter followed by any letter of V, W, Y, M, C, or K. The first special color (V), the second special color (W), yellow (Y), magenta When not distinguishing (M), cyan (C), and black (K), V, W, Y, M, C, and K are omitted.

  Further, under the toner cartridge 14, six image forming units 16 corresponding to the respective color toners are provided along the horizontal direction so as to correspond to the respective toner cartridges 14.

  An exposure device 40 (40V, 40W, 40Y, 40M, 40C) provided for each image forming unit 16 receives the image data subjected to the image processing by the image signal processing unit 13 from the image signal processing unit 13, and An image carrier 18 (18V, 18W, 18Y, 18M, 18C) described later is irradiated with a light beam L modulated in accordance with the image data.

  Each image forming unit 16 includes an image carrier 18 that is rotationally driven in one direction. By irradiating each image carrier 18 with the light beam L from each exposure device 40, an electrostatic latent image is formed on each image carrier 18.

  Around each image carrier 18, a corona discharge (non-contact charging) scorotron charger that charges the image carrier 18 and an electrostatic latent image formed on the image carrier 18 by the exposure device 40 are developed. A developing device that develops with the agent, a blade that removes the developer remaining on the image carrier 18 after transfer, and a static eliminator that radiates light by irradiating the image carrier 18 after transfer with light. . The scorotron charger, the developing device, the blade, and the charge eliminating device are arranged in this order from the upstream side to the downstream side in the rotation direction of the image carrier 18 so as to face the surface of the image carrier 18.

  A transfer unit 32 is provided below each image forming unit 16. The transfer unit 32 includes an annular intermediate transfer belt 34 that is in contact with each image carrier 18 and a primary transfer roll 36 that multi-transfers the toner image formed on each image carrier 18 to the intermediate transfer belt 34. Has been.

  The intermediate transfer belt 34 includes a drive roll 38 driven by a motor (not shown), a tension applying roll 41 that applies tension to the intermediate transfer belt 34, a counter roll 42 that faces a secondary transfer roll 62 described later, and a plurality of rolls. It is wound around the winding roll 44 and is circulated and moved in one direction (counterclockwise direction in FIG. 1) by the drive roll 38.

  Each primary transfer roll 36 is disposed opposite to the image carrier 18 of each image forming unit 16 with the intermediate transfer belt 34 interposed therebetween. The primary transfer roll 36 is applied with a transfer bias voltage having a polarity opposite to the toner polarity by a power supply unit (not shown). With this configuration, the toner image formed on the image carrier 18 is transferred to the intermediate transfer belt 34.

  On the opposite side of the drive roll 38 across the intermediate transfer belt 34, there is provided a removing device 46 that removes residual toner, paper dust and the like on the intermediate transfer belt 34 by bringing the blade into contact with the intermediate transfer belt 34. .

  Below the transfer unit 32, two sheet storage units 48 that store a sheet P as an example of a medium are provided along the horizontal direction.

  Each paper storage portion 48 can be pulled out from the first housing 10A. Above one end side (the right side in FIG. 1) of each paper storage unit 48, a delivery roll 52 that delivers the paper P from each paper storage unit 48 to the transport path 60 is provided.

  In each paper storage portion 48, a bottom plate 50 on which the paper P is placed is provided. The bottom plate 50 is lowered when the paper storage portion 48 is pulled out from the first housing 10A. When the bottom plate 50 is lowered, a space for the user to replenish the paper P is formed in the paper storage portion 48.

  When the sheet storage portion 48 pulled out from the first housing 10A is attached to the first housing 10A, the bottom plate 50 is raised. By raising the bottom plate 50, the uppermost sheet P placed on the bottom plate 50 and the delivery roll 52 come into contact with each other.

  A separation roll 56 is provided on the downstream side in the paper conveyance direction of the delivery roll 52 (hereinafter sometimes simply referred to as “downstream side”), and separates the paper P that has been delivered from the paper storage portion 48 one by one. ing. A plurality of transport rolls 54 that transport the paper P downstream in the transport direction are provided on the downstream side of the separation roll 56.

  The conveyance path 60 provided between the paper storage unit 48 and the transfer unit 32 returns the paper P sent out from the paper storage unit 48 to the left side in FIG. 1 by the first folding unit 60A, and further, the second folding unit 60B. 1 extends to the transfer position T between the secondary transfer roll 62 and the opposing roll 42 so as to be folded back to the right side in FIG.

  The secondary transfer roll 62 is applied with a transfer bias voltage having a polarity opposite to the toner polarity by a power feeding unit (not shown). With this configuration, the toner images of the respective colors that are multiplex-transferred onto the intermediate transfer belt 34 are secondarily transferred onto the paper P that has been transported along the transport path 60 by the secondary transfer roll 62.

  A preliminary path 66 extending from the side surface of the first housing 10 </ b> A is provided so as to join the second folding portion 60 </ b> B of the transport path 60. The paper P sent out from another paper storage unit (not shown) arranged adjacent to the first housing 10 </ b> A can enter the transport path 60 through the spare path 66.

  On the downstream side of the transfer position T, a plurality of conveyance belts 70 that convey the paper P on which the toner image has been transferred toward the second casing 10B are provided in the first casing 10A and conveyed to the conveyance belt 70. A transport belt 80 that transports the paper P downstream is provided in the second housing 10B.

  Each of the plurality of conveyance belts 70 and the conveyance belt 80 is formed in an annular shape and is wound around a pair of winding rolls 72. The pair of winding rolls 72 are respectively arranged on the upstream side and the downstream side in the transport direction of the paper P, and when one of them is rotationally driven, the transport belt 70 (transport belt 80) is moved in one direction (the timepiece in FIG. Cycle in the direction of rotation).

  A fixing unit 82 for fixing the toner image transferred onto the surface of the paper P to the paper P with heat and pressure is provided on the downstream side of the conveyance belt 80.

  The fixing unit 82 includes a fixing belt 84 and a pressure roll 88 disposed so as to contact the fixing belt 84 from below. A fixing unit N is formed between the fixing belt 84 and the pressure roll 88 to fix the toner image by pressurizing and heating the paper P.

  The fixing belt 84 is formed in an annular shape and is wound around the drive roll 89 and the driven roll 90. The drive roll 89 faces the pressure roll 88 from above, and the driven roll 90 is disposed above the drive roll 89.

  Each of the driving roll 89 and the driven roll 90 includes a heating unit such as a halogen heater. As a result, the fixing belt 84 is heated.

  As shown in FIG. 1, a conveyance belt 108 that conveys the paper P sent out from the fixing unit 82 to the downstream side is provided on the downstream side of the fixing unit 82. The conveyor belt 108 is formed in the same manner as the conveyor belt 70.

  A cooling unit 110 is provided on the downstream side of the conveyance belt 108 as a conveyance device that cools the paper P heated by the fixing unit 82.

  The cooling unit 110 includes an absorption device 112 that absorbs the heat of the paper P, and a pressing device 114 that presses the paper P against the absorption device 112. The absorption device 112 is disposed on one side (upper side in FIG. 1) with respect to the conveyance path 60, and the pressing device 114 is disposed on the other side (lower side in FIG. 1).

  The absorption device 112 includes an annular absorption belt 116 that contacts the paper P and absorbs the heat of the paper P. The absorbing belt 116 includes a driving roll 120 that transmits driving force to the absorbing belt 116, a plurality of winding rolls 118, and a steering roll 111 (details will be described later) for adjusting the position in the width direction of the absorbing belt 116. It is wrapped around.

  A heat sink 122 made of an aluminum material that dissipates heat absorbed by the absorption belt 116 by contacting the absorption belt 116 in a planar shape is provided on the inner peripheral side of the absorption belt 116.

  Further, the absorber 112 is provided with an upper belt position detector 26 as a detector in order to detect the position of the absorber belt 116 in the width direction.

  Further, a fan 128 for removing heat from the heat sink 122 and discharging hot air to the outside is disposed on the back side of the second housing 10B (the back side of the paper surface shown in FIG. 1).

  The pressing device 114 that presses the paper P against the absorbing device 112 includes an annular pressing belt 130 that conveys the paper P while pressing the paper P against the absorbing belt 116. The pressing belt 130 is wound around a plurality of winding rolls 132 and a steering roll 131 (details will be described later) for adjusting the position in the width direction of the pressing belt 130.

  The pressing device 114 is provided with a lower belt position detection unit 28 as a detection unit in order to detect the position of the pressing belt 130 in the width direction.

  On the downstream side of the cooling unit 110, there is provided a correction device 140 that conveys the paper P with the paper P interposed therebetween and corrects the curl of the paper P.

  An inline sensor 200 that detects a toner density defect, an image defect, an image position defect, and the like of the toner image fixed on the paper P is provided on the downstream side of the correction device 140.

  On the downstream side of the inline sensor 200, a discharge roll 198 that discharges the paper P on which an image is formed on one side to a discharge unit 196 attached to the side surface of the second housing 10B is provided.

  On the other hand, when images are formed on both sides, the paper P sent out from the inline sensor 200 is conveyed to a reversing path 194 provided on the downstream side of the inline sensor 200.

  The reversing path 194 includes a branch path 194A that branches from the transport path 60, a paper transport path 194B that transports the paper P transported along the branch path 194A toward the first housing 10A, and a paper transport path 194B. A reverse path 194 </ b> C is provided for turning the paper P transported along the reverse direction in the reverse direction to switch back and reverse the paper.

  With this configuration, the paper P that has been switched back in the reverse path 194 </ b> C is transported toward the first housing 10 </ b> A, and further enters the transport path 60 provided above the paper storage portion 48, to the transfer position T. It will be sent again.

  Next, an image forming process of the image forming apparatus 10 will be described.

  The image data that has been subjected to image processing by the image signal processing unit 13 is sent to each exposure device 40. In each exposure device 40, each light beam L is emitted according to image data, and is exposed to each image carrier 18 charged by a scorotron charger, thereby forming an electrostatic latent image.

  The electrostatic latent image formed on the image carrier 18 is developed by the developing device, and the first special color (V), the second special color (W), yellow (Y), magenta (M), and cyan (C). A toner image of each color of black (K) is formed.

  As shown in FIG. 1, each color toner image formed on the image carrier 18 of each of the image forming units 16V, 16W, 16Y, 16M, 16C, and 16K is composed of six primary transfer rolls 36V, 36W, 36Y, and 36M. , 36C, and 36K, multiple transfer is sequentially performed on the intermediate transfer belt.

  The color toner images transferred onto the intermediate transfer belt 34 are secondarily transferred onto the paper P conveyed from the paper storage unit 48 by the secondary transfer roll 62. The sheet P on which the toner image has been transferred is transported by the transport belt 70 toward the fixing unit 82 provided inside the second housing 10B.

  The toner images of the respective colors on the paper P are fixed on the paper P by being heated and pressurized by the fixing unit 82. Further, the paper P on which the toner image is fixed is cooled by passing through the cooling unit 110, and then sent to the correction device 140 to correct the curvature generated on the paper P.

  The paper P whose curvature is corrected is discharged to the discharge unit 196 by the discharge roll 198 after the inline sensor 200 detects an image defect or the like.

  On the other hand, when an image is formed on a non-image surface where no image is formed (in the case of double-sided printing), after passing through the inline sensor 200, the paper P is reversed by the reverse path 194 and provided above the paper storage unit 48. Then, the toner image is sent to the transport path 60 and a toner image is formed on the back surface in the above-described procedure.

  In the image forming apparatus 10 according to the present embodiment, the components for forming the images of the first special color (V) and the second special color (W) are added to the first casing as additional components according to the user's selection. 10A can be mounted. Accordingly, the image forming apparatus 10 does not include a part for forming the first special color and second special color images, and the image of any one of the first special color and the second special color. It is good also as a structure which has only the components for forming.

  Next, the configuration of the above-described steering rolls 111 and 131 of the cooling unit 110 will be described in detail. FIG. 2 is a diagram illustrating the configuration of the steering rolls 111 and 131 of the cooling unit 110.

  The cooling unit 110 includes an upper adjustment mechanism 124 that performs steering control for correcting the positional deviation of the absorption belt 116 in the width direction, and a lower adjustment mechanism that performs steering control for correcting the positional deviation of the pressing belt 130 in the width direction. 126 is provided.

  The upper adjustment mechanism 124 includes a steering roll 111, a swing arm 144, and an eccentric cam 142. When the upper belt position detection unit 26 detects the position in the width direction of the absorption belt 116 and a position shift in the width direction of the absorption belt 116 has occurred, the steering roll 111 is tilted to correct the position shift. Implement control.

  The lower adjustment mechanism 126 is also configured to include a steering roll 131, a swing arm 148, and an eccentric cam 146. When the position of the pressing belt 130 in the width direction is detected by the lower belt position detection unit 28 and a position shift in the width direction of the pressing belt 130 has occurred, the steering roll 131 is tilted to correct the position shift. Implement control.

  The eccentric cam 142 of the upper adjustment mechanism 124 and the eccentric cam 146 of the lower adjustment mechanism 126 are each driven to rotate by a steering drive section (upper steering drive section 22 and lower steering drive section 24 in FIG. 4) described later. The steering drive unit rotates the eccentric cams 142 and 146 to swing one end side of the swing arms 144 and 148. Thereby, the steering rolls 111 and 131 provided on the other end side of the swing arms 144 and 148 are inclined to correct the position of the belt.

  FIG. 3A shows a case where the belt (the absorption belt 116 and the pressing belt 130) is in a regular position. When the belt is traveling in a regular position in the width direction, the steering rolls 111 and 131 are almost horizontal. Is in a state.

  On the other hand, when the position in the width direction of the belt is detected by the belt position detection unit (the upper belt position detection unit 26 and the lower belt position detection unit 28), the steering drive unit is driven according to the deviation and the direction. The eccentric cams 142 and 146 are rotated to adjust the position of the belt.

  For example, as shown in FIGS. 3B and 3C, when the position in the width direction of the belt is deviated from the center to the outside, the steering drive unit is driven to rotate the eccentric cam 146. As a result, the swing arm 148 swings according to the rotation of the eccentric cam 146, and one end side of the steering roll 131 moves upward (FIG. 3B) or downward (FIG. 3C). As a result, the steering roll 131 is tilted from the horizontal, and the belt moves in the directions of the arrows in FIGS. 3B and 3C to correct the belt deviation. FIG. 3 shows an example in which the position of the pressing belt 130 is adjusted by the lower adjustment mechanism 126 as an example. When the position of the absorption belt 116 is adjusted by the upper adjustment mechanism 124, the direction of belt rotation is reversed from that in FIG.

  Next, the configuration of the control system of the image forming apparatus 10 according to the present embodiment will be described. FIG. 4 is a block diagram illustrating a configuration of a control system of the image forming apparatus 10 according to the present embodiment.

  The image forming apparatus 10 includes a control unit 20 as a control unit and a correction unit that perform control for performing image formation, the above-described steering control, and the like.

  Specifically, as shown in FIG. 4, the control device 20 includes a CPU 20A, a ROM 20B, a RAM 20C, and an input / output port 20D, each of which passes through a bus 20E such as an address bus, a data bus, and a control bus. Are connected to each other.

  Various programs such as a program for correcting an image and a program for performing the above-described steering control are stored in the ROM 20B, and various controls are performed by the CPU 20A developing and executing the program in the RAM 20C. It has become.

  Connected to the input / output port 20D are an upper steering drive unit 22 and a lower steering drive unit 24 as adjustment units, an upper belt position detection unit 26, a lower belt position detection unit 28, and a monitor 12 as a notification unit. Yes.

  The monitor 12 has a monitor such as a liquid crystal display, and displays a setting screen for performing various settings of the image forming apparatus 10, a display screen indicating the operation state of the image forming apparatus 10, and the like.

  As described above, the upper steering drive unit 22 and the lower steering drive unit 24 rotationally drive the eccentric cam 142 to adjust the position in the width direction of the belt, and the lower steering drive unit 24. Rotates the eccentric cam 146.

  The upper belt position detection unit 26 detects the position in the width direction of the absorption belt 116 and outputs the detection result to the control device 20. On the other hand, the lower belt position detection unit 28 detects the position in the width direction of the pressing belt 130 and outputs the detection result to the control device 20.

  That is, the control device 20 drives the upper steering drive unit 22 and the lower steering drive unit 24 based on the detection results of the upper belt position detection unit 26 and the lower belt position detection unit 28 to perform the steering control described above. To do. Specifically, the walk rate (movement distance in the belt width direction per unit movement distance in the belt conveyance direction) when the steering rolls 111 and 131 are tilted to a predetermined angle is stored in advance. Then, using the stored walk rate, the drive amount (rotation angle of the eccentric cams 142 and 146) of the steering drive unit (upper steering drive unit 22 and lower steering drive unit 24) is determined, and the control device 20 controls the steering drive unit. Control the drive.

  By the way, in the conveyance device using a pair of opposed belts such as the cooling unit 110, a change in the friction coefficient (μ) of the steering rolls 111 and 131 with the passage of time from the initial state, an increase in the friction coefficient of the sliding portion, and the like. As a result, the above-described walk rate changes. If the walk rate changes, there is a risk of poor adjustment when adjusting the position of the belt.

  Therefore, in the present embodiment, a walk rate measurement mode is provided to measure a change in the walk rate and correct the stored walk rate. As a result, by adjusting the drive amount of the steering drive unit (upper steering drive unit 22 and lower steering drive unit 24) when adjusting the belt position using the corrected walk rate, belt position adjustment failure can be reduced. Is prevented.

  The walk rate measurement mode is executed at a predetermined timing. For example, it is executed during image formation standby (so-called standby) by the image forming apparatus 10 waiting for conveyance. Alternatively, the walk rate measurement mode may be executed every time a predetermined number of image formations are completed. Alternatively, the walk rate measurement mode may be executed every predetermined time.

  In this embodiment, since the belts of the absorption device 112 and the pressing device 114 face each other in the cooling unit 110, when measuring the walk rate, one of the steering rolls 111 and 131 is set to the median value (substantially horizontal state). To fix. Then, the other steering rolls 111 and 131 are moved to measure the walk rate. Thereby, when the walk rate of one belt is measured, the influence of the other belt is reduced.

  In the present embodiment, the life of the belt is determined from the walk rate measured in the walk rate measurement mode and notified. Here, the term “life” refers to a state where the belt needs to be replaced or cleaned. When it is determined that the belt is at the end of its life, for example, the monitor 12 is notified by displaying that the belt needs to be cleaned or replaced. The life determination method determines whether or not the measured walk rate satisfies a predetermined life condition. For example, it is determined whether or not the measured walk rate is equal to or less than a predetermined threshold value.

  Next, a part of processing performed by the control device 20 of the image forming apparatus 10 according to the present embodiment configured as described above will be described. FIG. 5 is a flowchart illustrating an example of a flow of processing performed by the control device 20 of the image forming apparatus 10 according to the present embodiment. Note that the processing in FIG. 5 starts when the mode is shifted to the walk rate measurement mode. For example, the process is started when at least one of a transition to standby, a predetermined number of image formations, and a predetermined time have elapsed.

  In step 100, the control device 20 moves the position of one of the two steering rolls 111 and 131 to the center value and proceeds to step 102. That is, the control device 20 controls one of the upper steering drive unit 22 and the lower steering drive unit 24 to move the positions of the steering rolls 111 and 131 to the center value.

  In step 102, the control device 20 adjusts the position of the other steering roll 111, 131 of the two steering rolls 111, 131 to measure the walk rate, and proceeds to step 104. For example, the other steering roll 111, 131 is moved to a predetermined position, and the width direction position of the belt is detected by the belt position detection unit (the corresponding one of the upper belt position detection unit 26 and the lower belt position detection unit 28). The walk rate is measured by detecting. The predetermined position (movement amount) for moving the steering rolls 111 and 131 when measuring the walk rate is not limited to one position, but the belt position when moving to a plurality of positions and moving to each position. May be detected.

  In step 104, the control device 20 determines whether or not the measurement of the walk rate has been completed. For example, when measuring the walk rate by moving the steering rolls 111 and 131 to a plurality of positions, it is determined whether or not the measurement of the walk rate at all the positions is completed. If the determination is negative, the process returns to step 102 and the above processing is repeated. If the determination is affirmative, the process proceeds to step 106.

  In step 106, the control device 20 determines whether or not it is the life of the belt from the measured walk rate. In this determination, for example, it is determined whether or not the walk rate is equal to or less than a predetermined threshold value. If the determination is affirmative, the process proceeds to step 108, and if the determination is negative, the process proceeds to step 110. In step 104, when the walk rate is measured by moving the steering rolls 111 and 131 to a plurality of positions, the life of the belt is determined using the plurality of walk rates at each measured position. For example, as shown in FIG. 6A, if all of the plurality of (three) walk rate measurement results do not satisfy the predetermined life condition (OK in FIG. 6), the belt life has not been reached. to decide. On the other hand, if at least one of the plurality satisfies the life condition (NG in FIG. 6B), it is determined that the life of the belt. As a result, the life can be determined with high definition even when the influence of the other belt occurs as compared with the case where the walk rate is measured by moving the steering rolls 111 and 131 with a single adjustment amount. Here, in the example of FIG. 6, it determines with a lifetime, when it falls below the lifetime condition determination line predetermined as a lifetime determination condition. In addition, although an example in which the life of the belt is determined when one or more points satisfy the life condition has been described, the belt life may be determined when two or more points satisfy the life condition. Moreover, although the number of walk rate measurements is three in FIG. 6, it may be two or three or more.

  In step 108, the control device 20 performs control to display on the monitor 12 that the life of the belt (the absorption belt 116 or the pressing belt 130) on which the steering roll has been adjusted, and the series of processing ends. For example, the notification is made by displaying on the monitor 12 that the belt needs to be cleaned or replaced.

  On the other hand, in step 110, the control device 20 corrects the stored walk rate to the measured walk rate, and proceeds to step 112. As a result, since the walk rate corrected when adjusting the position of the belt is used, poor belt position adjustment is prevented.

  In step 112, the control device 20 moves the position of the other steering roll of the two steering rolls 111 and 131 to the center value, and proceeds to step 114. That is, the control device 20 moves the positions of the steering rolls 111 and 131 on which the walk rate is measured in step 102 to the center value.

  In step 114, the control device 20 adjusts the position of one of the two steering rolls 111 and 131, measures the walk rate, and proceeds to step 116. For example, one of the steering rolls 111 and 131 is moved to a predetermined position, and the position in the width direction of the belt is detected by the belt position detection unit (the corresponding one of the upper belt position detection unit 26 and the lower belt position detection unit 28). The walk rate is measured by detecting. The predetermined position (movement amount) for moving the steering rolls 111 and 131 when measuring the walk rate is not limited to one position, but the belt position when moving to a plurality of positions and moving to each position. May be detected.

  In step 116, the control device 20 determines whether or not the measurement of the walk rate has been completed. For example, when measuring the walk rate by moving the steering rolls 111 and 131 to a plurality of positions, it is determined whether or not the measurement of the walk rate at all the positions is completed. If the determination is negative, the process returns to step 114 and the above-described processing is repeated. If the determination is affirmative, the process proceeds to step 118.

  In step 118, the control device 20 determines whether or not it is the life of the belt from the measured walk rate. In this determination, it is determined whether or not the walk rate is equal to or lower than a predetermined threshold value. If the determination is affirmative, the process proceeds to step 108 described above. If the determination is negative, the process proceeds to step 120.

  In step 120, the control device 20 corrects the stored walk rate to the measured walk rate, and ends the series of processes. As a result, since the walk rate corrected when adjusting the position of the belt is used, poor belt position adjustment is prevented.

  In the above-described embodiment, the cooling unit has been described as an example of the transport device. However, the present invention is not limited to this, and a portion for transporting other paper in the image forming apparatus 10 may be applied.

  In the above-described embodiment, the example in which the positions of the absorption belt 116 and the pressing belt 130 are detected by the two detection units of the upper belt position detection unit 26 and the lower belt position detection unit 28 has been described. However, it is not limited to this. For example, one detection unit may be provided at a position where both belts can be detected, and the position of each of the absorption belt 116 and the pressing belt 130 may be detected by a single detection unit.

  In the above-described embodiment, the example in which the process of FIG. 5 is performed by causing the computer to execute a program that performs steering control has been described. However, a part or all of the process that is executed by the program that performs steering control is hardware. It may be performed by wear.

  The processing performed by the control device 20 of the image forming apparatus 10 according to the above embodiment may be stored in a storage medium as a program and distributed.

  Further, the present invention is not limited to the above, and it is needless to say that various modifications can be made without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 12 Monitor 20 Control apparatus 22 Upper steering drive part 24 Lower steering drive part 26 Upper belt position detection part 28 Lower belt position detection part 111,131 Steering roll 116 Absorption belt 124 Upper adjustment mechanism 126 Lower adjustment mechanism 130 Pressing belt 142, 146 Eccentric cam 144, 148 Swing arm

Claims (4)

A detection unit for detecting a position in the width direction of each of a pair of belts provided to face each other to convey a medium;
An adjustment unit for adjusting the width direction position of each of the belts;
Using the detection result of the detection unit and the movement distance in the belt width direction per unit movement distance in the belt conveyance direction when the width direction position of the belt is adjusted by the adjustment unit, the position of the belt is determined. A control unit that controls the adjustment unit to be in a predetermined position;
The width direction used in the control unit by using the detection result of the detection unit when one belt is fixed at a predetermined timing and the adjustment unit is controlled so that the other belt has a predetermined adjustment amount. A correction unit that corrects the movement distance to the movement distance in the width direction after change over time ;
Conveying device equipped with.   The conveying apparatus according to claim 1, further comprising a notifying unit that notifies the life of the belt when the moving distance in the width direction corrected by the correcting unit satisfies a predetermined life condition. The correction unit uses the detection result of the detection unit corresponding to each of the adjustment amount when controlling the adjusting unit to be a plurality of types of adjustment amount as the adjustment amount, wherein the predetermined, the plurality of types of adjustment the crosswise movement distance to be used in the control unit corresponding to each of the amount, and the correction in the width direction moving distance corresponding to each of the plurality of types of adjustment amount after aging,
3. The belt informing apparatus according to claim 2, wherein the informing section informs the life of the belt when the moving distance in the width direction corresponding to each of the plurality of types of adjustment amounts corrected by the correcting section satisfies a predetermined life condition. The conveying apparatus as described. The transport apparatus according to any one of claims 1 to 3,
An image forming unit that forms an image on a medium conveyed by the conveying device;
An image forming apparatus.