JP2018145009A - Conveying apparatus, image forming apparatus, and post-processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a position detecting means in a movable portion, and there is a problem that the position of the position detecting means shifts before and after moving the movable portion. SOLUTION: This is a transport device including position detecting means 100 to 102 for detecting the position of a transported medium and transport means for transporting the transported medium, and is provided with a fixing portion 32 and position detecting means 100 to 102. At the same time, between the first position where the position detecting means 100 to 102 are arranged at a position where the position of the conveyed medium can be detected and the second position different from the first position, the fixed portion 32 A movable portion 33 that is movable with respect to the movable portion 33 is provided, and an index portion 37 that serves as a reference position for calculating the amount of misalignment of the position detecting means 100 to 102 at the first position is provided in the fixed portion 32. [Selection diagram] FIG. 16

Description

  The present invention relates to a transport apparatus that transports a transported medium, an image forming apparatus including the transport apparatus, and a post-processing apparatus.

  For example, in an image forming apparatus such as a copying machine or a printer, when a transported medium such as paper or an OHP sheet is transported, an inclination amount (a skew amount) of the transported medium or a lateral shift amount in the width direction is detected. A technique for correcting the transported medium to the correct position and orientation is employed.

  As a transport apparatus that performs this type of position correction, Japanese Patent Application Laid-Open No. 2014-88263 discloses a transport that detects a positional deviation amount of a recording medium using a photosensor or a CIS (contact image sensor). A device has been proposed.

  By the way, if position detection means such as a photosensor or CIS is provided in a movable part such as a cover that opens and closes with respect to the apparatus main body, the position of the position detection means is shifted before and after the movable part is moved. Sometimes. In this case, it is necessary to correct the detected shift amount of the transported medium in accordance with the shift amount of the position detection unit.

  However, heretofore, such a problem has not been studied at all, and the displacement amount of the position detecting means accompanying the movement has not been grasped.

  In order to solve the above-described problems, the present invention provides a transport apparatus including a position detection unit that detects a position of a transported medium and a transport unit that transports the transported medium, the fixing unit, and the position detection unit. Between the first position where the position detecting means is disposed at a position where the position of the transported medium can be detected and the second position different from the first position. And an index portion serving as a reference position for calculating a positional deviation amount of the position detecting means at the first position is provided on the fixed portion. .

  According to the present invention, since the fixed portion is provided with the index portion serving as the reference position for calculating the amount of positional deviation of the position detecting means, the position detecting means is displaced due to the operation of the movable portion. However, the positional deviation amount of the position detection means can be calculated from the relative position of the position detection means with respect to the index portion.

1 is a schematic diagram illustrating an overall configuration of an image forming apparatus according to an embodiment of the present invention. It is the schematic of a clamping roller pair and its peripheral part. It is the schematic of a clamping roller pair and its peripheral part, Comprising: (a) is a top view, (b) is a side view. It is a perspective view of a clamping mechanism and a drive mechanism for driving the same. It is a figure for demonstrating position correction operation | movement, Comprising: (a) is a top view, (b) is a side view. It is a figure for demonstrating position correction operation | movement, Comprising: (a) is a top view, (b) is a side view. It is a figure for demonstrating position correction operation | movement, Comprising: (a) is a top view, (b) is a side view. It is a figure for demonstrating position correction operation | movement, Comprising: (a) is a top view, (b) is a side view. It is a figure for demonstrating position correction operation | movement, Comprising: (a) is a top view, (b) is a side view. FIG. 6 is a diagram for explaining a method for calculating a positional deviation of a sheet. It is a figure for demonstrating the correction amount of the width direction. It is a figure for demonstrating the pick-up operation of a clamping roller pair. It is a control flowchart which shows the flow to 1st correction | amendment. It is a block diagram of the control part which controls a clamping roller pair. It is a control flowchart which shows the flow of 2nd correction | amendment. It is a schematic block diagram of the conveying apparatus which concerns on this embodiment. It is a figure which shows the state which the movable part opened. It is a top view which shows typically the positional relationship of a parameter | index part and each CIS. It is a block diagram of the control part regarding calculation of the amount of position shift of CIS, and correction of a conveyance standard position. It is a flowchart which shows the flow after setting a conveyance reference position until it corrects. It is a figure for demonstrating the setting method of a conveyance reference position. It is a figure which shows the shift | offset | difference of the conveyance reference position accompanying the position shift of CIS. It is a figure for demonstrating the relative position of CIS with respect to a parameter | index part. It is a figure for demonstrating the calculation method of the positional offset amount of CIS, and the correction method of a conveyance reference position. It is a figure which shows the structure which provided the opening part which can be opened and closed in a movable part. 1 is a schematic diagram illustrating an overall configuration of an ink jet image forming apparatus. It is the schematic which shows the whole structure of a post-processing apparatus.

  Hereinafter, the present invention will be described with reference to the accompanying drawings. In the drawings for explaining the present invention, components such as members and components having the same function or shape are denoted by the same reference numerals as much as possible, and once described, the description will be given. Omitted.

First, the overall configuration and operation of an image forming apparatus according to an embodiment of the present invention will be described.
In FIG. 1, 1 is a copying machine as an image forming apparatus, 2 is a charging unit that charges the surface of a plurality of (in this case, four) photoconductors 5, and 3 is an exposure that irradiates each photoconductor 5 with exposure light L. , 4 is a developing unit for forming a toner image (image) on each photoconductor 5, 6 is a primary transfer unit (intermediate transfer belt) to which a toner image formed on the photoconductor 5 is primarily transferred, and 7 is toner. A secondary transfer unit (secondary transfer roller) for transferring an image from the primary transfer unit 6 to the paper P, 12 to 14 are a paper feeding unit (paper feeding cassette) in which the paper P is stored, and 20 is an unfixed on the paper P A fixing device for fixing an image, 21 is a fixing roller provided in the fixing device 20, 22 is a pressure roller provided in the fixing device 20, 30 is a conveying device that conveys the paper P along the conveying path, and 31 is a paper A pair of nipping rollers that correct the posture and position of the paper P while conveying the P ) Shows the. In addition to the function as a correction roller, the pair of nipping rollers 31 may have a function as a timing roller that adjusts the conveyance timing of the paper P to the secondary transfer unit 7 (changes the conveyance speed). Further, a separate timing roller may be arranged on the downstream side in the conveyance direction of the pair of clamping rollers 31.

With reference to FIG. 1 and FIG. 2, the operation during normal image formation in the copying machine 1 will be described.
First, the surface of each photoconductor 5 is uniformly charged to a predetermined polarity by the charging unit 2 (charging process). Next, exposure light L is irradiated from the exposure unit 3 to the surface of each photoconductor 5 based on image information obtained from a reading device or a computer, and an electrostatic latent image is formed on the surface of each photoconductor 5. (Exposure process). Then, toners of different colors (for example, yellow, magenta, cyan, black) are supplied from the developing unit 4 to the surface of each photoconductor 5 to form toner images of the respective colors (development process).

  Thereafter, the toner images of the respective colors formed on the respective photoreceptors 5 are primarily transferred so as to overlap the primary transfer unit 6 to form a color image, and then the secondary transfer unit 7 performs the secondary transfer onto the paper P. Is done.

  The paper P is transported from the paper feeding units 12 to 14 selected manually or automatically. For example, when one of the paper feed units 12 and 13 arranged in the copying machine 1 is selected, the paper P is fed by the paper feed roller 41 toward the first curved portion 200 (see FIG. 2) of the transport path. Sent. On the other hand, when the paper feeding unit 14 arranged outside the copying machine 1 is selected, the paper P is fed by the paper feeding roller 41 toward the second curved portion 300 (see FIG. 2) in the transport path. . The first music part 200 and the second music part 300 merge at the junction X and continue to the third music part 400 in the transport path. Therefore, the paper P fed from any of the paper feeding units 12 to 14 passes through the merging unit X and reaches the third music unit 400. Thereafter, the paper P passes through the straight conveyance path 500 and reaches the position of the pair of nipping rollers 31 constituting the alignment unit 51. Then, the position of the sheet P in the width direction and the skew direction is corrected by the pair of nipping rollers 31, and the sheet P is conveyed toward the secondary transfer unit 7.

  The sheet P is conveyed to the fixing device 20 after the toner image is transferred by the secondary transfer unit 7. The paper P transported to the fixing device 20 is fed between the fixing roller 21 and the pressure roller 22 and the toner image is fixed by applying heat and pressure. Then, the paper P is discharged from the copying machine 1.

  When performing duplex printing, as described above, the toner image is transferred to one side (front side) of the paper P through the charging process, the exposure process, and the development process, and the fixing device 20 performs the fixing process. After being broken, the paper P is transported to the reverse transport path 600 (see FIG. 1) without being discharged from the copying machine 1. The paper P transported to the reverse transport path 600 is switched back in the reverse transport path 600 (reversed in the transport direction), passes through the first curved section 200, the third curved section 400, and the straight transport path 500, and then becomes secondary again. It is conveyed to the transfer unit 7. Then, the toner image for the back surface formed through the charging process, the exposure process, and the development process is transferred to the paper P, and after the toner image is fixed by the fixing device 20, the paper P is discharged from the copying machine 1. .

  Although a series of image forming processes has been described above, it is also possible to select one of all the photoconductors 5 to form a single color image or to form a two-color or three-color image. is there.

  Next, the transport device 30 according to the present embodiment will be described in detail. In the following description, “upstream side in the transport direction” in the transport path is referred to as “upstream side”, and “downstream side in the transport direction” is referred to as “downstream side”.

FIG. 3A is a plan view of the sandwiching roller pair 31 and its periphery, and FIG. 3B is a side view thereof.
As shown in FIG. 3, the conveyance device 30 includes a plurality of CISs 100 to 102 as position detection units that detect the position of the paper P, a function as a conveyance unit that conveys the paper P, and a position that corrects the position of the paper P. A clamping roller pair 31 that also functions as a correcting unit is provided. The plurality of CISs 100 to 102 are, in order from the upstream side (the right side in the drawing) of the straight conveyance path 500, a first CIS (first position detection unit) 100, a second CIS (second position detection unit) 101, and a third CIS. The CIS (third position detecting means) 102 will be referred to. The first CIS 100 and the second CIS 101 are disposed on the upstream side of the sandwiching roller pair 31 and on the downstream side of the transport roller pair 44 serving as transport means on the upstream side of the sandwiching roller pair 31. Yes. On the other hand, the third CIS 102 is arranged on the downstream side of the sandwiching roller pair 31 and on the upstream side of the secondary transfer portion 7 {see FIG. 3B}. Each of the CISs 100 to 102 is arranged in parallel to the width direction of the paper P (direction orthogonal to the transport direction), and the relative positions of the paper P to the transport direction of the paper P and the pair of sandwiching rollers 31 and the like. The positional relationship with surrounding members is predetermined.

  In recent years, CIS uses a light emitting diode (LED) as a light source for the purpose of downsizing the device, and a contact image sensor (Contact Image Sensor) that directly reads an image with a linear sensor through a lens. (Sensor). Each of the CISs 100 to 102 can detect the side end portion Pa {see FIG. 3A} on one end side in the width direction of the paper P by a plurality of line sensors provided in the width direction of the paper P. . Note that the position detection means is not limited to the CIS, and may be any device that can detect the side edge Pa of the paper P, such as a plurality of photosensors arranged along the width direction of the paper P.

  The pair of nipping rollers 31 includes a correction in the width direction {correction for the positional deviation α in the width direction shown in FIG. 3A} and a skew correction {correction for the positional deviation β in the skew shown in FIG. 3A}. It functions as a matching unit 51 that performs a matching operation. Therefore, the nipping roller pair 31 is centered on the shaft portion 104a provided at the axial center position in the W direction {the sheet conveyance surface (conveyed medium conveyance surface) corresponding to the skew direction in FIG. It is configured to be able to rotate in the rotation direction} and to be movable in the S direction {direction corresponding to the paper width direction (conveyed medium width direction)} in FIG. Note that the sandwiching roller pair 31 may be configured to rotate in the W direction around the position on the end side in the axial direction.

FIG. 4 shows the configuration of the sandwiching roller pair 31 and a drive mechanism for driving it.
As shown in FIG. 4, the sandwiching roller pair 31 is a roller pair having a plurality of roller portions divided in the axial direction, and is rotationally driven by a first drive motor 61 as drive means (first drive means). Drive roller 31a and a driven roller 31b that rotates following the rotation of the drive roller 31a. The sandwiching roller pair 31 conveys the paper P by being driven to rotate while the paper P is sandwiched. The sandwiching roller pair 31 may be a roller pair having one roller portion that extends continuously in the axial direction without being divided in the axial direction.

  The first drive motor 61 is fixed to the frame of the transport device 30. A drive gear 61 a is provided on the motor shaft of the first drive motor 61, and the drive gear 61 a meshes with the gear portion 105 a of the frame-side rotation shaft 105 that rotates together with the drive roller 31 a of the pair of clamping rollers 31. As a result, when the first drive motor 61 is driven, the driving force is transmitted to the drive roller 31 a of the clamping roller pair 31 via the drive gear 61 a and the gear portion 105 a of the frame-side rotating shaft 105.

  The frame-side rotating shaft 105 is moved by the standing portion 104b of the base portion 104 so that the frame-side rotating shaft 105 can similarly move in the S direction as the sandwiching roller pair 31 moves in the S direction (direction corresponding to the paper width direction) in FIG. Held possible. The gear portion 105a of the frame side rotation shaft 105 is formed long enough in the axial direction so that the engagement with the drive gear 61a is maintained even if the frame side rotation shaft 105 moves in the S direction.

  The frame-side rotating shaft 105 and the driving roller 31a of the pair of sandwiching rollers 31 are coupled via a coupling 106 so as to be able to transmit driving. The coupling 106 includes a coupling (shaft joint) such as a constant velocity joint and a universal joint. As a result, even if the shaft angle with respect to the frame-side rotation shaft 105 changes as the pinching roller pair 31 rotates in the W direction in FIG. 4 (the rotation direction in the sheet conveyance surface corresponding to the skew direction), the rotation speed The driving force can be transmitted without any change.

  The driving roller 31a and the driven roller 31b of the pair of clamping rollers 31 are held rotatably around their respective axes by a holding member 72 formed in a substantially rectangular frame shape. The driving roller 31a and the driven roller 31b are each held so as to be movable in the S direction (axial direction) with respect to the holding member 72.

  The holding member 72 is supported so as to be rotatable in the W direction around the shaft portion 104a with respect to the base portion 104 that functions as a part of the frame of the transport device 30 (the copying machine 1). Furthermore, a second drive motor 107 is provided on one end side in the width direction of the base portion 104 as second drive means for rotating the holding member 72 in the W direction around the shaft portion 104a. A gear portion is formed on the surface of the motor shaft 107 a of the second drive motor 107, and this gear portion meshes with a gear portion 72 a formed on one end side in the width direction of the holding member 72. Accordingly, when the second drive motor 107 is rotationally driven in the forward and reverse directions, the holding member 72 and the pair of clamping rollers 31 held by the second drive motor 107 rotate in the W direction around the shaft portion 104a. The motor shaft 107a of the second drive motor 107 is provided with a known encoder so that the rotation amount in the W direction and the forward / reverse direction with respect to the reference position of the sandwiching roller pair 31 are indirectly detected. Has been. In addition, a sufficient gap is provided between the support column 72b on one end side of the holding member 72 and the gear portion 72a, and even if the drive roller 31a and the driven roller 31b slide and move to one end side in the width direction, These rotating shafts are configured not to interfere with the gear portion 72a.

  The frame of the transport device 30 (the copying machine 1) is provided with a third drive motor 108 as third drive means for moving the clamping roller pair 31 in the S direction. A pinion gear is formed on the motor shaft 108 a of the third drive motor 108, and this pinion gear meshes with a rack gear portion 109 provided on the other axial end side of the frame side rotating shaft 105. The rack gear unit 109 is provided so as to be rotatable relative to the frame-side rotation shaft 105, and is configured to slide in the S direction without rotation even when the frame-side rotation shaft 105 rotates.

  The driving roller 31a and the driven roller 31b of the sandwiching roller pair 31 are connected to each other via a connecting member 110 so that they can move in the S direction together. The connecting member 110 is disposed between the coupling 106 and the holding member 72, and is sandwiched between retaining rings 111 provided on the respective rotation shafts of the driving roller 31a and the driven roller 31b. With such a configuration, when the third drive motor 108 is rotationally driven in the forward and reverse directions, the sandwiching roller pair 31 moves in the S direction. Further, a known encoder is provided on the motor shaft 108a of the third drive motor 108 so that the movement amount in the S direction and the forward / reverse direction with respect to the reference position of the pair of clamping rollers 31 are indirectly detected. Has been.

  Hereinafter, the correction operation for correcting the position of the sheet will be described with reference to FIGS. 3 and 5 to 15.

  The paper P sent out from the paper supply unit to the transport device 30 is transported further downstream by the transport roller pair 44 and passes through the first CIS 100 (FIG. 3). When the leading end portion Pb of the paper P reaches the second CIS 101 (FIG. 5), the position of the paper P is detected (hereinafter referred to as “first detection”). Based on the result of the first detection, the positional deviation amount of the paper P in the width direction and the skew positional deviation amount are calculated.

  Specifically, the calculation of the positional deviation amount in the width direction of the paper P based on the result of the first detection is performed based on the position in the width direction of the paper P detected by the second CIS 101 (the side edge portion Pa in the width direction of the paper P). Is compared with a transport reference position K indicated by a straight line parallel to the transport direction in FIG. That is, the distance K1 in the width direction between these positions is calculated as the positional deviation amount α in the width direction of the paper P.

  Next, the positional deviation amount of the skew of the paper P can be calculated from the difference in the end position in the width direction of the paper P detected by each of the first CIS 100 and the second CIS 101. That is, as shown in FIG. 10, when the leading end Pb of the paper P reaches the second CIS 101, the distance K1 and the distance K2 in the width direction from the conveyance reference position K are the first CIS 100 and the second CIS. Detected by CIS 101. Since the conveyance direction distance M1 between the first CIS 100 and the second CIS 101 is determined in advance, tan β = (K1−K2) / M1 and the skew position with respect to the conveyance direction of the paper P A deviation amount β is obtained.

  Based on the positional deviation amount α in the width direction of the paper P and the skew positional deviation amount (skew angle) β obtained as described above, the width direction correction and the skew correction of the paper P are performed by the sandwiching roller pair 31. (This is hereinafter referred to as “first correction”). The amount of skew correction is the skew angle β. The correction amount in the width direction is calculated based on the positional deviation amount α and the skew angle β in the width direction. For example, as shown in FIG. 11, the skew-corrected sheet P ′ having the skew angle β changes in the amount of positional deviation in the width direction from α to α ′. This positional deviation amount α ′ is calculated and used as the correction amount α ′ in the width direction by the pair of nipping rollers 31 (however, the correction amount α ′ varies depending on which position is used to correct the skew angle correction). To do.)

  Here, the sandwiching roller pair 31 is disposed at the reference position shown in FIG. 3A before the first detection. Then, until the sheet P is conveyed to the pair of sandwiching rollers 31, the pair of sandwiching rollers 31 performs a reception operation of moving in the direction opposite to the direction of the first correction by the amount of movement by the first correction. Specifically, as shown in FIG. 12, before the sheet P is sandwiched, the pair of sandwiching rollers 31 rotates about the shaft portion 104a by the angle β in the direction of the arrow W1 and in the direction of the arrow S1. Translate by distance α ′. As a result, the shaft portion 104a moves to the position of the shaft portion 104a ′. Such a pick-up operation is performed by the clamping roller pair 31 after the first detection until the clamping roller pair 31 clamps the paper P (FIG. 5).

  When the leading end portion Pb of the paper P reaches the sandwiching roller pair 31, the sandwiching roller pair 31 grips the paper P (FIG. 6). At this time, as shown in FIG. 6B, the transport roller pair 44 on the upstream side of the sandwiching roller pair 31 is separated from each other, and the sheet P is not sandwiched.

  As shown in FIG. 6A, when the first correction is started, the pair of sandwiching rollers 31 causes the positional deviation amount of the sheet P obtained from the first detection result while sandwiching and transporting the sheet P. Based on this, the position of the sheet P in the skew direction is corrected by rotating in the direction of the arrow W2 around the shaft portion 104a, and the position of the sheet P in the width direction is corrected by moving in parallel in the direction of the arrow S2. To do. Thus, the first correction by the sandwiching roller pair 31 is completed, and the position of the paper P is corrected (FIG. 7).

  FIG. 13 shows a control flow up to the first correction described above, and FIG. 14 shows a block diagram of a control unit related to the first correction.

  As shown in FIG. 13, first, the first CIS 100 and the second CIS 101 detect the paper P (step N1), and the positional deviation amount α in the width direction of the paper P and the positional deviation amount β of the skew are determined. Calculated (step N2). Then, based on the calculated misregistration amounts α and β, a correction amount α ′ in the width direction is calculated (step N3), and a correction amount for the first correction (a skew correction amount β and a correction amount α ′ in the width direction). ) Is determined.

  Based on this correction amount, the encoder count is calculated by each encoder (see FIG. 14) (step N4).

  Then, the determined count number is input to a controller for driving the nipping roller pair 31. Then, according to the input count number, the second drive motor 107 and the third drive motor 108 are driven by the respective motor drivers, and the nipping roller pair 31 rotates in the rotation direction (W direction) in the sheet conveyance surface. Or moving in the width direction (S direction), the pick-up operation is performed (step N5). After the nipping roller pair 31 nipping the paper P, the driving of the motors 107 and 108 causes the nipping roller pair 31 to rotate or move in the direction opposite to the pick-up operation while conveying the paper P, and the first correction is performed. Performed (step N6). During the pick-up operation and the first correction, the encoder feeds back the positional information of the pinching roller pair 31 from moment to moment, and controls the pinching roller pair 31 to move by a determined amount of movement. Thereby, the position of the pinching roller 31 after the completion of the first position correction becomes closer to the reference position. However, it does not always return to the reference position by the second correction described later.

  As described above, in the present embodiment, the position correction (first correction) of the paper P is performed based on the positional deviation amount of the paper P obtained from the detection results of the first CIS 100 and the second CIS 101. The correction alone may not be sufficient for the positional accuracy required for the paper P.

  In other words, after the first detection, when the paper P is sandwiched between the sandwiching roller pair 31, a force may be applied to the paper P from the sandwiching roller pair 31, and the position of the paper P may be further shifted. Further, it is also conceivable that the position of the paper P is shifted during the correction of the position of the paper P by the sandwiching roller pair 31 and the conveyance to the downstream side. Further, a correction error at the time of the first correction may be considered.

  Therefore, in the transport apparatus according to the present embodiment, the second correction for correcting the position of the paper P is further performed after the first correction. Hereinafter, the second correction will be described.

  After the first correction, when the leading end Pb of the paper P reaches the third CIS 102 (FIG. 8), the position of the paper P is detected again by the third CIS 102 and the second CIS 101 (this will be referred to as the following). , Referred to as “second detection”). Based on the result of the second detection, the amount of misalignment of the paper P is calculated.

  The calculation of the positional deviation amount of the paper P based on the result of the second detection is performed in the same manner as in the first detection, and the detection results of the two CISs provided on the upstream side and the downstream side in the conveyance direction of the paper P are calculated. Based on. That is, the positional deviation amount α in the width direction is obtained from the position in the width direction (position of the side end portion Pa in the width direction) of the paper P obtained by the third CIS 102. Further, the skew displacement amount of the paper P is calculated from each position in the width direction of the paper P obtained by the second CIS 101 and the third CIS 102 and the transport direction distance between the CIS 101 and 102. (In the second detection, the second CIS 101 replaces the first CIS 100 during the first detection, and the third CIS 102 replaces the second CIS 101 during the first detection. Will be detected.)

  Then, based on the positional deviation amount of the paper P calculated from the result of the second detection, the nipping roller pair 31 moves in the direction of the arrow S3 shown in FIG. The second correction is performed by rotating in the direction of arrow W3 about 104a.

  FIG. 15 shows a control flow of the second correction.

  In the second correction, first, the paper P is detected by the second CIS 101 and the third CIS 102 (step N11), and the positional deviation amount (the positional deviation amount in the width direction and the positional deviation amount of the paper P is determined in the same manner as the first correction). A skew position deviation amount) is calculated (step N12). Then, a correction amount is calculated from the calculated positional deviation amount (step N13), and an encoder count number is calculated (step N14). Then, according to the calculated encoder count number, the second drive motor 107 and the third drive motor 108 are driven by the respective motor drivers, and the second correction is performed (step N15).

  In the second correction, the position information of the paper P is detected every moment by the second CIS 101 and the third CIS 102 after the correction is started. Then, the positional deviation amount of the paper P is calculated based on the positional information and fed back to the control unit, and the positional correction amount (encoder count number) of the paper P is corrected every moment. By performing this feedback control, it is possible to reduce the positional deviation of the paper P that occurs during the second correction, the correction error during the second correction, and the like, and it is possible to perform more accurate correction. . However, the second correction may be performed based on the correction amount calculated when the leading edge of the paper P first reaches the third CIS 102 without performing this feedback control.

  As described above, the sheet P subjected to the first correction and the second correction is conveyed toward the secondary transfer unit 7 by the pair of clamping rollers 31. When the sheet P reaches the secondary transfer unit 7 (FIG. 9), the pair of nipping rollers 31 is separated from the sheet P and returns to the reference position again in preparation for position correction and conveyance of the next sheet P {FIG. ) Returns to the reference position by movement in the direction of arrow S4 and rotation in the direction of arrow W4 about the shaft 104a}.

FIG. 16 is a schematic configuration diagram of a transport apparatus according to the present invention.
As shown in FIG. 16, the conveyance device 30 according to the present embodiment has a pair of nipping rollers 31, three CISs 100 to 102, conveyance guides 120a and 120b, and a secondary transfer unit (secondary transfer unit) to facilitate maintenance work and the like. The transfer roller) 7 and the like are configured to be detachable from the copying machine main body (image forming apparatus main body) as one unit. Also, as shown in FIG. 17, the transport device 30 according to the present embodiment makes it easier for the jammed paper to be removed in the transport device 30, so that the upper part in the figure is compared to the lower part. It can be opened and closed (oscillated). That is, the conveyance device 30 includes a fixed portion (a lower portion that is not opened / closed) 32, a first position in a closed state shown in FIG. 16 with respect to the fixed portion 32, and an open state shown in FIG. The movable portion (upper portion that is opened and closed) 33 is movable between the second position and the second position.

  The fixed portion 32 is provided with a pair of nipping rollers 31, a lower conveyance guide 120b, and a secondary transfer portion 7. On the other hand, the movable portion 33 is provided with an upper conveyance guide 120a and the CISs 100 to 102. The movable portion 33 is configured to be swingable in the vertical direction about a support shaft 36 fixed to the fixed portion 32. The movable portion 33 is provided with a cover member 34 that covers the upper portion of the transport guide 120a and the upper portions of the CISs 100 to 102, and a handle portion 35 is provided on the upstream side of the cover member 34. The user pushes up the handle portion 35 by hand and swings the movable portion 33 upward about the support shaft 36, whereby the movable portion 33 can be opened (state shown in FIG. 17). As a result, the upper conveyance guide 120a and the CISs 100 to 102 move to the retracted position away from the lower conveyance guide 120b, so that it becomes easy to perform a paper jam handling operation.

  However, in the configuration in which the CIS is provided in the movable part as in the transport apparatus according to the present embodiment, the position of the CIS may be deviated from the position before opening and closing by opening and closing the movable part. If a CIS misregistration occurs, an error also occurs in the amount of misregistration of the sheet obtained from the CIS detection result, so that the accuracy in correcting the position of the sheet decreases.

  Therefore, in the transport apparatus according to the present embodiment, in order to prevent a decrease in paper position correction accuracy due to the above-described CIS positional deviation, the amount of CIS positional deviation is grasped, and based on this, the amount of paper misalignment is determined. The transport reference position is corrected. This will be described in detail below.

  As shown in FIG. 16, in the transport device 30 according to the present embodiment, an index portion 37 serving as a reference position for calculating the amount of positional deviation of each CIS 100 to 102 is provided in the fixed portion 32. Specifically, the indicator portion 37 is formed of a white sheet and is attached to the upper surface of the lower conveyance guide 120b with a double-sided adhesive tape or the like.

FIG. 18 is a plan view schematically showing the positional relationship between the indicator portion 37 and each of the CISs 100 to 102. In FIG. 18, the CISs 100 to 102 are arranged on the lower side of the drawing with respect to the transport path, contrary to the configuration shown in FIG.
As shown in FIG. 18, the indicator portion 37 is disposed at a position facing each of the CISs 100 to 102. Here, the positions where the CISs 100 to 102 are opposed to each other are the first position in which the movable portion 33 is closed as shown in FIG. 16, and the positions where the CISs 100 to 102 can detect the position of the paper. In this state, each CIS 100 to 102 is a position facing the lower conveyance guide 120b (fixed portion 32). In addition, the indicator unit 37 is disposed on the outer side in the width direction with respect to the conveyance area (maximum conveyance area) D through which the maximum width size of paper P that can be conveyed passes so as not to prevent the CIS 100 to 102 from detecting the position of the paper. Has been.

FIG. 19 is a block diagram of a control unit relating to the calculation of the CIS positional deviation amount and the correction of the conveyance reference position.
As shown in FIG. 19, the control unit 52 records the sheet conveyance reference position and the relative position of each of the CISs 100 to 102 with respect to the index unit 37, and the conveyance that calculates the amount of misalignment of the sheet with respect to the conveyance reference position. A misregistration calculation unit 54; a detection misregistration calculation unit 55 that calculates the misregistration amount of each CIS 100-102; and a conveyance reference correction unit 56 that corrects the conveyance reference position based on the misregistration amount of each CIS 100-102. Prepare.

  Hereinafter, with reference to the flowchart shown in FIG. 20, a detailed process and function in the control unit 52 and a flow from setting the conveyance reference position to correcting it will be described.

  First, the transport reference position is set. The conveyance reference position is set before the use of the copying machine (for example, an adjustment process before shipment), and the conveyance reference position is set according to the relative positional relationship with each CIS 100-102. Specifically, as shown in FIG. 21, a reference sheet 60 as a conveyance reference setting member is placed at a position facing each of the CISs 100 to 102, and a linear end 60 a extending in the sheet conveyance direction of the reference sheet 60 is provided. Detected by each CIS 100-102. Then, the distances L1 to L3 in the width direction from the ends of the CISs 100 to 102 to the linear end 60a of the reference sheet 60 are recorded in the recording unit 53 as position information for determining the conveyance reference position. As a result, the position of the straight end 60a of the reference sheet 60 is set as the conveyance reference position K. After the conveyance reference position is set, the reference sheet 60 becomes unnecessary and is removed.

  Thereafter, when the use of the copying machine is started, the sheet position is normally corrected based on the set transport reference position. When the sheet is conveyed, the conveyance position deviation calculation unit 54 calculates the amount of deviation of the sheet with respect to the conveyance reference position based on the position information of the sheet detected by each of the CISs 100 to 102. The nipping roller pair 31 corrects the position of the sheet based on the calculated amount of misalignment of the sheet. The detailed positional deviation amount calculation method and the correction operation are as described above.

  Here, when the opening / closing operation of the movable portion 33 is performed, it is conceivable that the positions of the CISs 100 to 102 are slightly shifted from the positions before the opening / closing. If the positions of the CISs 100 to 102 are shifted by γ1 to γ3 in the width direction (upward in the figure) as shown in FIG. 22, the position of the transport reference position K (the end of each CIS 100 to 102) Since the positions of the distances L1 to L3 in the width direction from the portion are also shifted by the same amount, the conveyance reference position K is the position of the alternate long and short dash line K ′. However, since the sheet position cannot be corrected with high accuracy as it is, it is necessary to calculate the shift amounts γ1 to γ3 of the CISs 100 to 102 and to correct the transport reference position by the shift amount.

  Therefore, in this embodiment, before the opening / closing operation of the movable unit 33 is performed (for example, during the adjustment time after the setting of the conveyance reference position and before the start of sheet conveyance), the CISs 100 to 102 for the index unit 37 are set. The relative position is detected, and this is recorded as the initial position (position before opening / closing) of each CIS 100-102. Specifically, the position of the index part 37 is detected by each CIS 100 to 102 in a state where the movable part 33 is closed and each CIS 100 to 102 faces the index part 37, and the end part of each CIS 100 to 102 shown in FIG. The distances T1 to T3 in the width direction from the corresponding index part 37 to the corresponding index part 37 are recorded in the recording part 53.

  Thereafter, when the opening / closing operation of the movable part 33 is performed, the relative position (position after opening / closing) of each CIS 100 to 102 with respect to the index part 37 is detected again and recorded. That is, as shown in FIG. 24, the recording unit 53 records the width direction distances T1 ′ to T3 ′ from the end portions of the CISs 100 to 102 after the opening / closing operation to the corresponding index units 37.

  Then, based on the relative position information (T1 to T3) recorded first and the relative position information (T1 ′ to T3 ′) newly recorded, the detected position deviation calculation unit 55 performs each CIS 100 to the index unit 37. The positional deviation amounts γ1 to γ3 of 102 are calculated. The positional deviation amounts γ1 to γ3 of each CIS 100 to 102 are obtained by the following formulas (1) to (3). Note that the positional deviation amounts γ1 to γ3 are not necessarily the same value. For example, when each of the CISs 100 to 102 is displaced in the skew direction of the paper, the respective displacement amounts γ1 to γ3 have different values.

γ1 = T1−T1 ′ (1)
γ2 = T2−T2 ′ (2)
γ3 = T3−T3 ′ (3)

  Then, based on the calculated misregistration amounts γ1 to γ3 of the CISs 100 to 102, the conveyance reference correction unit 56 corrects the width direction distances L1 to L3, which are the position information of the recorded conveyance reference positions. Specifically, as shown in the following formulas (4) to (6), the corrected width direction distance L1 is obtained by subtracting the positional deviation amounts γ1 to γ3 of the CISs 100 to 102 from the width direction distances L1 to L3. “˜L3” is obtained.

L1 ′ = L1−γ1 Expression (4)
L2 ′ = L2−γ2 Expression (5)
L3 ′ = L3-γ3 Expression (6)

  In this way, the corrected width direction distances L1 ′ to L3 ′ are updated as new position information and recorded in the recording unit 53 by correcting the width direction distances L1 to L3, which are the position information of the conveyance reference position. Is done. As a result, the transport reference position is corrected to the correct position (the position of the one-dot chain line K).

  Thereafter, when the opening / closing operation of the movable portion 33 is further performed, the relative position information (T1 ″ to T3 ″) of each CIS 100 to 102 with respect to the indicator portion 37 is acquired again, and the information acquired immediately before this is acquired. Based on the relative position information (T1 ′ to T3 ′), the positional deviation amounts of the CISs 100 to 102 are newly calculated using the above formulas (1) to (3). Then, the updated width direction distances L1 ′ to L3 ′, which are the position information of the conveyance reference position, are corrected using the above formulas (4) to (6) based on the calculated displacement amounts of the CISs 100 to 102. To do.

  Thereafter, each time the opening / closing operation of the movable unit 33 is performed, the relative position information of each CIS 100 to 102 with respect to the indicator unit 37 is re-acquired, and compared with the relative position information acquired immediately before, the CIS 100 to 102 A positional deviation amount is calculated, and the previous transport reference position information is corrected based on the calculated positional deviation amount.

  As described above, according to the present embodiment, since the indicator portion serving as the reference position for calculating the amount of CIS misalignment is provided in the fixed portion, misalignment occurs in the CIS with the opening / closing operation. Even so, the amount of CIS misregistration can be calculated from the relative position of the CIS with respect to the index portion. As a result, the conveyance reference position can be corrected, so that a paper misalignment detection error caused by the CIS misalignment can be reduced, and the paper position can be corrected with high accuracy.

  As shown in FIG. 16, in this embodiment, a plurality of CISs 100 to 102 are attached to a single conveyance guide 120a integrally formed. By being configured in this way, compared to the case where each CIS 100-102 is attached to a separate member, variation in the position of each CIS 100-102 due to the attachment error of the member can be reduced, and the paper position detection The accuracy can be improved.

  On the other hand, the clamping roller pair 31 is provided in a fixed portion 32 which is a module different from the movable portion 33 provided with the CISs 100 to 102. By being configured in this way, the vibration generated when the clamping roller pair 31 operates is not easily transmitted to the CISs 100 to 102, and the decrease in the detection accuracy of the CISs 100 to 102 due to the vibrations can be suppressed.

  Moreover, you may provide the opening part 40 which can be opened and closed by the cover member 39 in the location corresponding to each CIS100-102 of the cover member 34 like the structure shown in FIG. In particular, as shown in FIG. 25, by providing the opening 40 above the place where the fixing member 38 for fixing each CIS 100 to 102 to the conveyance guide 120 a is provided, the mounting operation of the CIS 100 to 102 through the opening 40 or Removal work can be easily performed.

  As mentioned above, although embodiment of the conveying apparatus which concerns on this invention was described, this invention is not limited to the above-mentioned structure, Of course, a various change can be added in the range which does not deviate from the summary of this invention. .

  In the above-described configuration, the present invention is applied to a transport apparatus that transports paper. However, the present invention is not limited to paper (including plain paper, cardboard, thin paper, coated paper, label paper, envelopes, etc.), but also an OHP sheet. The present invention can also be applied to a recording medium on which an image such as an OHP film is printed, or a conveyance device that conveys a sheet such as a document. Furthermore, the present invention is not limited to a sheet such as a recording medium or a document, but can also be applied to a transport device that transports a transported medium such as an electronic substrate.

  Further, the conveying device according to the present invention is not limited to the one mounted on the color image forming apparatus as shown in FIG. 1, but the one mounted on the monochrome image forming apparatus or the image forming apparatus other than the electrophotographic system (for example, Ink jet type image forming apparatus, offset printing machine, etc.) may be used.

FIG. 26 shows an example of a transport device mounted on an inkjet image forming apparatus.
An image forming apparatus 700 illustrated in FIG. 26 includes an image forming unit 701 including a plurality of ejection heads 705 that eject ink by an inkjet method, a paper feeding unit 702 that supplies paper, a transport device 706 that transports paper, and an image. A drying unit 703 that dries the paper on which the paper is formed, and a paper discharge unit 704 that discharges the dried paper. The transport device 706 includes a plurality of CISs 708 to 710 serving as position detecting means for detecting the position of the paper on the transport path from the paper feeding unit 702 to the image forming unit 701, and the detection results of the papers based on the detection results of the CISs 708 to 710. A clamping roller pair 711 is provided as position correcting means for performing position correction. The paper supplied from the paper supply unit 702 is corrected by the position in the width direction or the skew direction based on the detection results of the CISs 708 to 710 while being conveyed by the pair of nipping rollers 711 and then to the image forming unit 701. It is conveyed. The image forming unit 701 forms an image by ejecting ink of each color from the ejection head 705 onto the paper. Thereafter, the paper is dried by the drying unit 703 and then discharged to the paper discharge unit 704.

  In such an inkjet image forming apparatus 700, if the CISs 708 to 710 are provided on a movable part such as a cover member, it is considered that the CISs 708 to 710 are displaced due to the operation of the movable part. Therefore, as in the above-described embodiment, the positional deviation of each CIS 708 to 710 can be calculated by providing the fixed portion with the index portion 37 serving as a reference position for calculating the positional deviation amount of each CIS 708 to 710. Will be able to. As a result, it is possible to reduce the detection error of the paper misalignment due to the misalignment of the CIS, and to perform the paper position correction with high accuracy.

  The conveying device according to the present invention can also be applied to a post-processing device that performs post-processing on paper discharged from the image forming apparatus.

FIG. 27 shows an example of a transfer device mounted on the post-processing device.
A post-processing device 900 illustrated in FIG. 27 includes a receiving unit 901 that receives a sheet discharged from the image forming apparatus 1, a conveying device 902 that conveys the received sheet, and a half-folding process, a binding process, or a punching process for the sheet. A post-processing unit 903 that performs post-processing such as the above and a discharge unit 904 that discharges paper are mainly configured.

  The paper received from the receiving unit 901 into the post-processing device 900 is either the first transport path 210 that passes through the post-processing unit 903 or the post-processing by a plurality of transport roller pairs (transport means) 905 provided in the transport device 902. The sheet is transported to the second transport path 220 that continues to the discharge section 904 without passing through the section 903. In addition, the conveyance device 902 includes a plurality of CISs 906 to 908 as position detection means for detecting the position of the sheet, and each CIS 906 on the upstream side of the branching portion Y where the first conveyance path 210 and the second conveyance path 220 are branched. Are provided with a pair of clamping rollers 909 as position correcting means for correcting the position of the sheet based on the detection results of ˜908. While the paper is being conveyed by the pair of nipping rollers 909, the position correction in the width direction or the skew direction is performed based on the detection results of each of the CISs 906 to 908, and then to the first conveyance path 210 or the second conveyance path 220. Be transported.

  Here, each of the CISs 906 to 908 is held by a movable part 910 provided so as to be movable with respect to the main body of the post-processing apparatus, and the movable part 910 is moved in the horizontal direction (for example, orthogonal to the paper surface of FIG. The CIS 906 to 908 can be exposed from the main body of the post-processing apparatus by being moved to the front side in the direction. In such a configuration, it is conceivable that the displacement of the CISs 906 to 908 occurs due to the operation of the movable unit 910. Therefore, similarly to the above-described image forming apparatus, the amount of displacement of each CIS 906 to 908 is calculated. An index portion 37 serving as a reference position may be provided on a fixed portion such as a conveyance guide. As a result, it is possible to calculate the misregistration of each of the CISs 906 to 908, and it is possible to reduce paper misregistration detection errors caused by the CIS misregistration.

1 Copying machine (image forming device)
30 Conveying device 31 Nipping roller pair (position correction means)
32 fixed part 33 movable part 34 cover member 37 index part 40 opening part 52 control part 53 recording part 54 conveyance position deviation calculation part 55 detection position deviation calculation part 56 conveyance reference correction part 900 post-processing apparatus K conveyance reference position P sheet (covered) Transport medium)

JP 2014-88263 A

Claims (10)

Position detecting means for detecting the position of the transported medium;
A transport device comprising transport means for transporting the transported medium,
A fixed part;
Between the first position where the position detection means is provided and the position detection means is arranged at a position where the position of the transported medium can be detected, and a second position different from the first position. And a movable part movable with respect to the fixed part,
2. A transport apparatus according to claim 1, wherein an index portion serving as a reference position for calculating a positional deviation amount of the position detecting means at the first position is provided on the fixed portion.   The transport apparatus according to claim 1, further comprising: a detection position deviation calculation unit that calculates a position deviation amount of the position detection unit with respect to the index unit based on a position detection result of the index unit by the position detection unit.   The transport reference position set based on the relative positional relationship with the position detection unit is corrected based on the calculated positional shift amount of the position detection unit as a reference position for calculating the amount of positional shift of the transported medium. The transport apparatus according to claim 2, further comprising a transport reference correction unit. Position detecting means for detecting the position of the transported medium;
A recording unit that records a conveyance reference position set by a relative positional relationship with the position detection unit as a reference position for calculating a positional deviation amount of the medium to be conveyed;
A transport position deviation calculating unit that calculates a position deviation amount of the transported medium with respect to the transport reference position based on a position detection result of the transported medium by the position detecting unit;
A transport device comprising transport means for transporting the transported medium,
A fixed part;
Between the first position where the position detection means is provided and the position detection means is arranged at a position where the position of the transported medium can be detected, and a second position different from the first position. And a movable part movable relative to the fixed part,
An index portion provided at a position of the fixed portion facing the position detecting means when the movable portion is in the first position;
A detection position deviation calculation unit that calculates a position deviation amount of the position detection unit with respect to the index unit based on a position detection result of the index unit by the position detection unit;
A transport apparatus comprising: a transport reference correction unit configured to correct the transport reference position based on the calculated positional deviation amount of the position detection unit. A plurality of the position detection means,
The transport apparatus according to any one of claims 1 to 4, wherein each position detection means is attached to a single member.   6. The apparatus according to claim 1, further comprising a position correcting unit that functions as the transport unit and corrects a position of the transported medium based on a positional deviation amount of the transported medium obtained from a detection result of the position detecting unit. The conveyance apparatus of any one of Claims.   The transport apparatus according to claim 6, wherein the position correction unit is provided in the fixed portion. The movable part includes a cover member that covers the position detection means,
The transport apparatus according to claim 1, wherein an opening that can be opened and closed is provided at a location corresponding to the position detection unit of the cover member.   An image forming apparatus comprising the transport device according to claim 1. A post-processing apparatus that performs post-processing on a transported medium discharged from an image forming apparatus,
A post-processing apparatus comprising the transport device according to claim 1.

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