JP2006160435A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To smoothly convey curled print paper at a printing section, in a printer equipped with a conveying pass for conveying the print paper which is set in a paper setting section to the printing section. <P>SOLUTION: This printer includes a switch-back unit U4 which is provided between a cutter unit U2 and a print unit U5, receives and holds the print paper P conveyed from the cutter unit U2, and which delivers the held print paper P to the print unit U5. The switch-back unit U4 delivers the print paper P in a direction inclined to a straight line which connects an abutment part 41c and a guide surface 74a of the rollers 41 by a predetermined angle θ when viewed from a print paper width direction so that a front end of the curled print paper P may reach the guide surface 74a of a guide member 74. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention pulls out a long print paper set in a roll form around a paper set unit from the paper set unit and conveys it to the print unit, and the print unit prints on the print surface of the print paper. Belongs to the technical field related to printers.

  In general, a printer used in a photographic printing system or the like includes a paper set unit on which print paper is set, and a conveyance path for pulling out the print paper set in the paper set unit from the paper set unit and conveying it to the print unit. And. In this print unit, printing is performed by ejecting ink from the print head to the print paper, and the print paper printed by the print unit is discharged to the outside.

In the printer as described above, like the conventional photographic image forming apparatus, the print paper is transported by a number of pressure-type rollers that sandwich the print paper, and the paper set unit has a roll shape. A long paper wound around the paper is set, and the roller is used to pull out the print paper from the paper set unit and continuously convey it to the print unit without cutting (see, for example, Patent Documents 1 to 3). ).
JP 2003-237156 A JP-A-9-86754 JP 2000-289904 A

  However, when the print paper is continuously conveyed without being cut from the paper set portion to the print portion as in the above-described conventional printer, the print paper in the print portion has an influence of the paper set state on the paper set portion. Accordingly, the print paper is easily inclined in the width direction. In this print unit, the ink discharge nozzles of the print head are arranged in a line in the paper transport direction, and when the print paper is slightly inclined in the width direction, for example, the ink discharged from each of the upstream end and the downstream end of the nozzle line The landing positions of the two are greatly shifted from each other in the paper width direction, which adversely affects the print quality.

  Accordingly, it is conceivable to cut the print paper while it is being conveyed from the paper set unit to the print unit.

  However, even if the print paper is cut, it is difficult to reduce the inclination of the print paper in the width direction as long as the print paper is continuously conveyed by a plurality of rollers from the paper set portion to the print portion. That is, if the paper is continuously conveyed by the roller, it is conveyed while being influenced by the paper set state in the paper setting unit, and if the print paper is conveyed by the roller, errors such as the roller shape are slight. It becomes easy to skew.

  Therefore, in the middle of transporting the print paper from the paper set section to the print section, in the middle of the transport path for transporting the print paper set in the paper set section to the print member in order to transport the print paper by means other than rollers. It is conceivable to provide a paper transport device that is transported from the upstream transport path and receives and grips the print paper, and sends the gripped print paper to the downstream transport path. However, when the paper transport device is provided, it is necessary to transfer the print paper between the upstream transport path and the paper transport device, and the print paper is transferred between the paper transport device and the downstream transport path. There is a need.

  Here, when a long paper wound in a roll shape is adopted as the print paper, the print paper is curled by the curl. For this reason, there is a possibility that a paper jam or the like may occur particularly when the print paper is transferred from the paper transport device to the downstream transport path. That is, there is a possibility that the transfer of the print paper may not be smoothly performed due to the curl at the end of the print paper.

  The present invention has been made in view of such a point, and an object of the present invention is to provide a printer having a conveyance path for conveying the print paper set in the paper set unit to the print unit as described above. Is to smoothly convey the curled print paper.

  In order to achieve the above-mentioned object, the present invention cuts a paper set part for accommodating a paper roll, and a cut in the middle of a conveyance path for conveying the print paper set in the paper set part to the print part. And a paper transport device that receives and grips the printed paper cut by the cutting device and sends the gripped print paper to the downstream transport path. The paper transport device is configured by the winding roll of the paper roll. When the curled print paper is sent out, the front end position of the print paper is shifted due to the curl, and the print paper feed direction is inclined in advance to the side opposite to the direction in which the end portion is shifted.

  Specifically, the first invention includes a paper set unit in which a paper roll in which a long print paper is wound in a roll shape is set, a print unit that performs printing on a print surface of the print paper, There is provided a printer comprising an upstream conveyance path for pulling out and conveying the print paper set in the paper set section from the paper set section, and a downstream conveyance path for conveying the print paper to the printing section. It is a target.

  A cutting means provided in the upstream conveyance path and configured to cut the printed paper drawn from the paper set section into a predetermined length, and provided between the upstream conveyance path and the downstream conveyance path, and cut. And a paper transport device that receives and grips the printed paper and sends the gripped print paper to the downstream transport path.

  In addition, the paper transport device is configured so that the front end of the printed paper curled by the winding roll of the paper roll reaches the upstream end of the downstream transport path, as viewed in the print paper width direction, and the paper transport device and the paper transport device. Print paper is sent out in a direction inclined by a predetermined angle with respect to a straight line connecting the upstream end of the downstream conveyance path.

  In the case of the above configuration, in the configuration in which the print paper is conveyed from the paper set unit to the print unit in order from the upstream side through the upstream conveyance path, the paper conveyance device, and the downstream conveyance path, the upstream side where the conveyance path changes. It is necessary to deliver the print paper between the transport path and the paper transport apparatus and between the paper transport apparatus and the downstream transport path.

  Here, the printed paper set in the paper set section is formed in a convex shape when viewed in the paper width direction on the side facing the outside when the paper is wound in a roll shape by a paper roll curl. Curled.

  Then, the print paper fed from the paper transporting device has its front end separated from the paper transporting device and then reaches the upstream end of the downstream transport path until it reaches the upstream side of the front end. Only the portion in contact with the transport device is in a cantilever state supported by the paper transport device. In other words, since the print paper has a free end at the downstream side (front end) of the print paper in contact with the paper conveying device, when the print paper is curled, the print paper is curled. Curved according to shape.

  Here, suppose that a straight line connecting the paper transport device and the upstream end of the downstream transport path to which the print paper is transferred, when the print paper feed direction sent from the paper transport device is viewed from the print paper width direction. , The front end of the printed paper sent out from the paper transporting device is displaced from the feeding direction according to the curl of the printed paper, so that it does not reach the upstream end of the downstream transport path well. The print paper cannot be accurately delivered to a conveyance means such as a conveyance roller provided in the conveyance path.

  Therefore, when the printed paper curled by the paper roll winding reel is sent out from the paper transporting device to the downstream transport path, the sending direction of the sent out print paper is such that the front end of the curled print paper is the downstream transport path. When viewed in the print paper width direction, it is configured to be inclined at a predetermined angle with respect to a straight line connecting the paper transport device and the upstream end of the downstream transport path. Then, the predetermined angle is set so that the front end of the curled print paper sent out from the paper transport device accurately reaches the upstream end of the downstream transport path. Specifically, it is preferably set based on the curl amount of the print paper, the linear distance between the paper transport device and the upstream end of the downstream transport path, and the like. That is, print paper having a predetermined curl amount is sent out in a direction inclined by a predetermined angle with respect to a straight line connecting the paper transport device and the upstream end of the downstream transport path, and the front end of the print paper is in the direction of the straight line. A predetermined angle is set so that the front end of the printed paper reaches the upstream end of the downstream transport path when the paper transport device advances by a distance between the paper transport device and the upstream end of the downstream transport path. The front end of the printed paper immediately after being sent out at the predetermined angle set in this way is not directed toward the upstream end of the downstream conveyance path. However, as the print paper is fed out, the front end of the print paper is curved according to the curl and gradually proceeds toward the upstream end of the downstream conveyance path. When the front end of the print paper advances by a distance between the paper transport device and the upstream end of the downstream transport path in the straight direction, the front end of the print paper reaches the upstream end of the downstream transport path. Thus, even when the print paper is curled, the print paper can be easily transferred between the paper transport device and the downstream transport path only by changing the angle in the feeding direction.

  Further, the printed paper conveyed from the upstream conveying path is gripped by the paper conveying device, and then the gripped print paper is sent out to the upstream end of the downstream conveying path. As described above, since the print paper is gripped and transported by the paper transport device, it is not transported by the rollers in the transport section by the paper transport device. In addition, since the print paper gripped by the paper transport device is no longer on the upstream transport path and is separated from the upstream transport path, the long paper wound in a roll shape in the paper set section The paper is conveyed to the printing unit without being affected by the set state of the paper, and the print quality can be improved.

  In a second aspect based on the first aspect, the predetermined angle is adjusted according to a curl amount of the printed paper.

  As described above, the predetermined angle for the front end of the print paper delivered from the paper transport device to accurately reach the upstream end of the downstream transport path is the curl amount of the print paper, the print paper from the paper transport device. , The distance between the paper transport device and the upstream end of the downstream transport path (for example, the distance in the horizontal direction), and the like. Here, the curl amount of the print paper is determined by the paper quality of the print paper, the roll diameter of the roll in the paper set unit, and the like, and changes every time printing is performed. If the curl amount changes, the amount by which the front end of the print paper deviates from the sending direction when the print paper is sent out from the paper conveying device by a certain length also changes. Therefore, in the above configuration, the predetermined angle, that is, the angle formed by the straight line connecting the paper transport device and the upstream end of the downstream transport path, and the print paper feed direction sent out from the paper transport device, It is adjusted according to the curl amount of the print paper. As described above, by adjusting the predetermined angle according to the curl amount of the print paper, the curled print paper can be moved downstream from the paper transport device even if printing is continuously executed or printing is performed for different print papers. It can be reliably delivered to the side conveyance path.

  According to the present invention, the paper transporting device sets the print paper feeding direction from the paper transporting device so that the front end of the curled print paper reaches the upstream side of the downstream transporting path. When viewed in the direction, the print paper is curled by the curl of the paper roll in the paper set section by inclining by a predetermined angle with respect to the straight line connecting the paper transport device and the upstream end of the downstream transport path. However, the print paper can be easily transferred from the paper transport device to the downstream transport path.

  At the same time, a paper transport device is provided in the middle of the transport path from the paper set section to the print section to receive and grip the print paper transported from the upstream transport path and send the gripped print paper to the downstream transport path. As a result, the number of paper transport rollers can be reduced, the inclination of the print paper in the width direction in the print unit can be reduced, and the print quality can be improved.

  According to the second aspect of the present invention, even if the curl amount of the print paper is changed by adjusting the predetermined angle according to the curl amount of the print paper, depending on the paper quality of the print paper, the roll diameter in the paper set portion, or the like. The curled print paper can be reliably and easily delivered from the paper transport device to the downstream transport path.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows an inkjet printer according to an embodiment of the present invention. This ink jet printer is used for a photographic print system, and is connected via a communication cable to a receiving block 100 (see FIG. 9) that acquires image data and order information and performs necessary correction processing and the like. The image data transmitted from the receiving block 100 via the communication cable is printed on the print paper P based on the order information.

  The ink jet printer includes a housing 1, a magazine housing portion 2 disposed in the lower portion of the housing 1, a cassette housing portion 3 disposed in a substantially central portion in the vertical direction in the housing 1, and a housing. A print unit 4 that is disposed in an upper part of the body 1 and prints image data on the print paper P; a first transport path for transporting the print paper P from the magazine housing unit 2 to the print unit 4; A second transport path for transporting the print paper P from the cassette housing unit 3 to the print unit 4 and a second transport path for discharging the print paper P printed by the print unit 4 from the print unit 4 to the outside of the housing 1. 3 and a discharge tray 5 provided outside the housing 1 and receiving the print paper P discharged to the outside of the housing 1 through the third conveyance path. The front-rear direction of the case is the left-right direction in FIG. 1, the front side of the case is the right side of FIG. 1, and the rear side of the case is the left side of FIG. The left-right direction of the housing is a direction perpendicular to the paper surface of FIG.

  In the magazine accommodating portion 2, a print paper P, which is a long paper, is set as a paper roll R wound in a roll shape and accommodated and held in the paper magazine 8. The print paper P is wound so that the print surface to be printed is on the outside. On the other hand, a plurality of print papers P, which are cut sheets, are set in the cassette storage unit 3 while being stored and held in a rectangular box-shaped paper feed cassette 9. The print paper P in the paper feed cassette 9 is stacked in the thickness direction (vertical direction) with the print surface facing upward, and is pressed against a later-described feed roller 35 positioned above by the pressing plate 10. Yes. The magazine housing unit 2 and the cassette housing unit 3 constitute a paper set unit in which the print paper P is set. Then, the print paper P set in the magazine housing unit 2 or the cassette housing unit 3 is conveyed to the printing unit 4 as described later, printed by the printing unit 4, and discharged to the discharge tray 5. ing. In the magazine housing 2, it is also possible to set two print papers P having a small width in parallel in the left-right direction of the housing, and when two are set in parallel in this way, The set two print papers P are simultaneously pulled out from the magazine housing unit 2 and conveyed in two rows. The print unit 4 prints the two print papers P and discharges them simultaneously to the discharge tray.

  In the casing 1, a first supply unit U1, a cutter unit U2, a second supply unit U3, a switchback unit U4, and a print unit U5 are provided to constitute the first to third transport paths. The first transport path is composed of a first supply unit U1, a cutter unit U2, a switchback unit U4, and a print unit U5 in order from the magazine accommodating portion 2. Further, the second transport path is configured by a second supply unit U3, a switchback unit U4, and a print unit U5 in order from the cassette housing portion 3. Further, the third transport path is constituted by a print unit U5.

  The first supply unit U1 is provided in the magazine housing portion 2 (paper magazine 8). The first supply unit U1 includes three support rollers 15 that support the roll-shaped print paper P, a guide member 16 that guides the print paper P to the cutter unit U2, and a print member that is provided in the middle of the guide member 16. A pressure supply roller 17 composed of driving and driven rollers 17a and 17b for transporting the paper P to the cutter unit U2, and a guide roller 18 provided on the upstream side of the guide member 16 and around which the print paper P is wound. It has. Of the three support rollers 15, a roller disposed on the front side of the casing is rotationally driven by an electric motor (not shown) to apply a rotational force to the print paper P around the center of the roll. Further, the drive roller 17a of the supply roller 17 is fed by an electric motor 30 disposed in the cutter unit U2 via a transmission belt 31 and a gear train 19 and a later-described feed roller 25 disposed in the cutter unit U2. The drive roller 25a is rotationally driven. A first paper detection sensor 20 is provided at the downstream end of the first supply unit U1, and when the print paper P is all pulled out from the magazine housing portion 2 by the first paper detection sensor 20, the first paper detection sensor 20 is provided. The rear end of the print paper P is detected. When the rear end of the print paper P is detected, the fact is notified to the operator via a display or the like.

  The cutter unit U2 is disposed on the rear side of the housing of the first supply unit U1 in a state of being fixed to the vertical frame 6 extending in the vertical direction, and is a crimp-type delivery unit that sends out the print paper P to the switchback unit U4. A cutting roller 25, a cutter 26 that is disposed downstream of the feeding roller 25 and that cuts the print paper P and includes a fixed blade 26 a and a movable blade 26 b, a drive mechanism that drives the movable blade 26 b, and the like And a guide member 28 that extends in the horizontal direction and feeds the print paper P from the roller 25 to a cutting position by the cutter 26. The cutter 26 cuts the print paper P drawn from the magazine housing unit 2 to a predetermined length based on the order information from the receiving block 100. The feed roller 25 includes one drive roller 25 a and two driven rollers 25 b that sandwich the print paper P, and these driven rollers 25 b are pressed against the drive roller 25 a by one compression coil spring 29. As described above, the drive roller 25a is rotationally driven by the electric motor 30 through the transmission belt 31 together with the drive roller 17a of the supply roller 17 in the first supply unit U1. The print paper P is moved rearward in the horizontal direction by the feed roller 25 and the guide member 28 and sent to the switchback unit U4, and is received by the roller pair 41 of the switchback unit U4 as will be described later. After being gripped, it is cut by the cutter 26. The roller pair 41 may receive the print paper P after cutting instead of receiving the print paper P before cutting. However, in this case, since the conveyance path in the cutter unit U2 becomes long, it is preferable to receive it before cutting.

  The first supply unit U1 and the cutter unit U2 constitute an upstream conveyance path for pulling out and conveying the print paper P from the magazine accommodating portion 2, and the guide member 28 located at the downstream end of the cutter unit U2. The downstream end 28a constitutes the downstream end of the upstream conveyance path.

  The second supply unit U3 includes a feed roller 35 that comes into contact with the print surface of the print paper P positioned at the top of a plurality of print papers P (cut sheet paper) set in the cassette housing unit 3, and the feed roller 35. And an electric motor 36 that drives the cutting roller 35 through a gear train 37. By driving the feeding roller 35, only one print paper P located at the top moves horizontally in the rearward direction of the housing. Then, it is sent out to the switchback unit U4. The second supply unit U3 constitutes an upstream conveyance path for pulling out and transporting the print paper P from the cassette housing portion 3, and the feed roller 35 is a downstream end of the upstream conveyance path for the cassette housing portion 3. Configure.

  The switchback unit U4 constitutes a paper transport device / switchback device provided between an upstream transport path and a downstream transport path, which will be described later, in the middle of the transport path. The switchback unit U4 receives the print paper P conveyed from the upstream conveyance path, and enters the downstream conveyance path (that is, the print unit U5) in the direction opposite to the print paper movement direction when the print paper P is received. It is designed to send out. That is, in the upstream conveyance path, the print paper P is conveyed toward the rear side of the housing with the print surface facing upward, and in the downstream conveyance path provided at a position above the upstream conveyance path, The paper P is transported toward the front side of the casing opposite to the upstream transport path with the print surface facing upward. However, in the switchback unit U4, the traveling direction of the print paper P faces the print surface upward. In this state, the print paper P is reversed without being bent so that the print paper P can be smoothly transferred from the upstream transport path to the downstream transport path without bending the print paper P.

  Specifically, the switchback unit U4 includes a gripping member that receives and grips the print paper P transported from the upstream transport path. In the present embodiment, the gripping member is configured as a roller pair 41 that is configured to be rotatable forward and backward about the central axis, and is opposed to each other in the vertical direction, and sandwiches the print paper P therebetween. One (the roller in contact with the back surface of the print paper P in this embodiment) is the driving roller 41a, and the other (the roller in contact with the print surface of the print paper P) is the driven roller 41b. The drive roller 41a is rotationally driven around the central axis by an electric motor 42 and a transmission belt 43 (see FIGS. 2 and 3) as a drive mechanism. By forward rotation and reverse rotation, the printing paper P is received and retracted from the upstream conveying path, and the printing paper P is sent to the downstream conveying path. Note that both rollers of the roller pair 41 may be driven, and the functions of driving and driven may be reversed up and down.

  The roller pair 41 is linearly moved in the vertical direction by the moving mechanism at the housing rear side position of the cutter unit U2, the second supply unit U3, and the print unit U5. As shown in FIGS. 2 and 3, the moving mechanism includes a rail mount 45 that is fixed to the vertical frame 6 (see FIG. 1) and extends in the vertical and horizontal directions, and one end of the rail mount 45 in the horizontal direction of the casing. A traveling rail 46 attached to the section so as to extend in the vertical direction, and a driving belt 48 that is wound around two pulleys 47 provided near the upper and lower ends of the traveling rail 46 and extends along the traveling rail 46. And an electric motor 49 attached and fixed to the rail mount 45 and directly connected to the lower pulley 47. The drive belt 48 is driven forward and reverse by the electric motor 49. A bracket 50 is attached and fixed to the drive belt 48, and a slide member 51 that fits and slides on the travel rail 46 is fixed to the bracket 50, and the drive belt 48 is driven forward and backward by the electric motor 49. As a result, the bracket 50 reciprocates in the vertical direction. The vertical position of the bracket 50 can be determined by measuring the amount of movement (for example, the amount of rotation of the motor) from a reference position (for example, the lowermost end) where a sensor or the like for detecting the bracket 50 is provided. .

  A support plate 52 is fixed to the bracket 50, and one end portion of the driving roller 41a in the roller pair 41 is rotatably supported by the support plate 52. At the same time, a driven roller 41b is provided in contact with the drive roller 41a above the drive roller 41a, and the driven roller 41b is forward and reverse around the central axis of the drive roller 41a by a rotation mechanism 90 described later. Are integrally connected to the drive roller 41a. As a result, the roller pair 41 linearly moves in the vertical direction as the bracket 50 moves. Although not shown, the other end of the drive roller 41a is supported by a support portion formed at the other end in the left-right direction of the housing of the rail mount 45 so as to be slidable in the vertical direction. The other end of the driven roller 41b is connected to the other end of the driving roller 41a by a similar rotating mechanism that operates in conjunction with the rotating mechanism 90.

  The above-described electric motor 42 for driving the drive roller 41a is fixed to the support plate 52. Pulleys 54 are fixed to the rotating shaft of the electric motor 42 and one end of the driving roller 41a. The transmission belt 43 is wound around both pulleys 54, and the driving roller is passed through the transmission belt 43. 41a is driven.

  As shown in FIGS. 2 and 3, the rotating mechanism 90 includes an electric motor 91 that generates rotational power (shown only in FIG. 3), a rotating disk 92 that is rotationally driven by the electric motor 91, and a rotating disk 92. And an arm member 93 that rotates in conjunction with the arm member 93. The electric motor 91 is fixed to the support plate 52, and a pulley 91a is provided on the rotating shaft thereof. The rotating disk 92 is located on the inner side of the support plate 52 in the left-right direction of the housing and is rotatably supported by the support plate 52. A pulley 92a is provided at one end located on the outer side in the left-right direction of the casing with respect to the support plate 52 of the rotating shaft of the rotary disk 92, and the transmission belt 91b is wound around the pulley 91a of the electric motor 91. ing. The rotary disk 92 is rotationally driven by an electric motor 91 via a transmission belt 91b. A projecting pin 92 b is provided at a position eccentric from the center of rotation of the rotating disk 92 on the inner side surface in the left-right direction of the casing of the rotating disk 92. The arm member 93 is located on the inner side of the rotating disc 92 in the left-right direction of the housing, and a base end portion is rotatably supported by one end portion of the driving roller 41a. A long hole 93a that opens in the left-right direction of the housing is formed at the tip of the arm member 93, and a projecting pin 92b of the rotary disk 92 is inserted into the long hole 93a. Further, the arm member 93 rotatably supports the driven roller 41b disposed so as to contact the driving roller 41a between the base end portion and the tip end portion. The rotating mechanism 90 configured as described above rotates the rotating disk 92 by the electric motor 91 so that the projecting pin 92b provided on the rotating disk 92 rotates around the rotation axis of the rotating disk 92. While the projecting pin 92b slides in the elongated hole 93a, the arm member 93 is rotated about the center axis of the driving roller 41a. As a result, the driven roller 41b supported by the arm member 93 also rotates about the central axis of the driving roller 41a while being in contact with the driving roller 41a as the arm member 93 rotates. By doing so, the inclination in the tangential direction at the contact portion 41c between the drive roller 41a and the driven roller 41b changes (arrow in the figure). The state in which the driving roller 41a and the driven roller 41b are positioned in the vertical direction is defined as the basic posture of the roller pair 41, and the roller pair 41 assumes the basic posture unless otherwise described below.

  The roller pair 41, the electric motor 42, the transmission belt 43, the bracket 50, the slide member 51, the support plate 52, a first support member 56, a second support member 57, a pressing roller 59, and a rotation mechanism 90 described later are used as gripping members. The movable transfer unit u40 is configured.

  By the moving mechanism, the movable transport unit u40 is provided at a receiving position for receiving the print paper P from the upstream transport path and at a position spaced apart from the receiving position by a predetermined distance on the downstream side. It moves linearly between the delivery position and the delivery position. That is, the receiving position for receiving the print paper P from the cutter unit U2 (hereinafter referred to as the first receiving position) is substantially the same height position as the downstream end of the cutter unit U2 (position near the lower end of the traveling rail 46, see FIG. 1). The height position substantially the same as the downstream end of the second supply unit U3 (substantially the central position in the vertical direction of the traveling rail 46, see FIG. 4) is a receiving position (hereinafter referred to as receiving the print paper P from the second supply unit U3). , Referred to as a second receiving position). On the other hand, the height position substantially the same as the upstream end of the print unit U5 (position near the upper end of the traveling rail 46, see FIG. 5) is the sending position for sending the print paper P to the print unit U5. Thus, the downstream end of the upstream conveyance path and the upstream end of the downstream conveyance path are separated by a predetermined distance (a value determined by the arrangement of the units U1 to U5 and set to the smallest possible value). Correspondingly, the movable transport unit u40 moves.

  The switchback unit U4 receives the print paper P from the upstream conveyance path (cutter unit U2) by the roller pair 41 at the first receiving position, and after the print paper P is cut by the cutter 26, Alternatively, after receiving and gripping the print paper P from the upstream conveyance path (second supply unit U3) by the roller pair 41 at the second receiving position, the roller pair 41 that grips the print paper P by the moving mechanism is The print paper P is moved to the sending position while being separated from the upstream conveyance path, and the print paper P is moved to the downstream conveyance path in the direction opposite to the moving direction of the print paper P when receiving the print paper P at the sending position. It is configured to send out. The print paper P is sent out from a contact portion 41c (hereinafter, simply referred to as a contact portion of the roller pair 41) between the driving roller 41a and the driven roller 41b of the roller pair 41, and the print paper P is sent to the downstream conveyance path. The direction is a horizontal direction that is a tangential direction of the contact portion 41c, and is opposite to the moving direction at the time of receiving (facing forward of the housing).

  As shown in FIG. 2, a first support for supporting the print paper P is located below the print paper P held by the roller pair 41 at the front of the casing of the roller pair 41 in the support plate 52. The member 56 is fixed (not shown in FIG. 3). The first support member 56 has a function of receiving the front end of the print paper P sent from the downstream end 28a of the guide member 28 of the cutter unit U2 and guiding it to the roller pair 41 at the receiving position. Specifically, the first support member 56 includes, on the front side of the casing of the roller pair 41, a horizontal portion 56a extending in the horizontal direction from the vicinity of the contact portion 41c between the driving roller 41a and the driven roller 41b toward the front side of the casing. A bent portion 56b bent downward from the front end of the horizontal portion 56a. The switchback unit U4 as a paper transport device receives the print paper P sent out from the downstream end 28a by the first support member 56. The first support member 56 is provided with a second paper detection sensor 58 for detecting the print paper P.

  On the other hand, as shown in FIG. 2, the support plate 52 has a rear portion of the casing of the roller pair 41 located below the print paper P gripped by the roller pair 41 and supports the print paper P. The support member 57 is fixed (not shown in FIG. 3). A bent portion bent downward is formed at the rear portion of the housing of the second support member 57, and a presser roller 59 is in contact with the bent portion. The presser roller 59 is rotatably attached to the tip of the arm 60 that is rotatably supported by the support plate 52, and abuts against the bent portion of the second support member 57 by the weight of the presser roller 59. ing. The bent portion of the second support member 57 and the pressing roller 59 prevent the printed paper P gripped by the roller pair 41 from dropping down and coming into contact with the rear inner wall surface of the housing 1. That is, on the rear side of the switchback unit U4 in the casing 1 (the portion corresponding to the moving range of the roller pair 41 on the opposite side of the upstream conveyance path and the downstream conveyance path with respect to the roller pair 41). Is provided with a space 12 for the print paper P that is gripped by the roller pair 41. By hanging the print paper P downward as described above, the front and rear direction of the space space 12 in the front and rear of the housing is provided. The length along the (upstream direction of the upstream conveyance path) can be made as small as possible. On the other hand, by hanging the print paper P downward, the space 12 for the print paper P gripped by the roller pair 41 is below the portion corresponding to the moving range (below the first receiving position). Although it is necessary to extend, in the present embodiment, with respect to the first transport path, the upstream transport path located on the upstream side of the switchback unit U4 and the first receiving position are set to the print paper P set in the magazine housing portion 2. Therefore, the space 12 can be easily extended downward without increasing the height of the housing 1.

  Although not shown, restriction members for restricting the movement of the print paper P in the width direction are provided at both ends of the first and second support members 56 and 57 in the paper width direction. Both regulating members are configured to be able to change the interval in accordance with the paper width (the width of the paper can be determined by detecting the identification code portion provided in the paper magazine 8). When the print paper P is conveyed in two rows as described above, another regulating member enters the conveyance path at the center between the two regulating members, and is conveyed in two rows by these three regulating members. The movement of each printed paper P in the width direction is restricted.

  The print unit U5 is provided at a fixed base 65 fixed to a horizontal frame 7 extending in the horizontal direction at the upper end position of the vertical frame 6, and is provided at an intermediate portion in the vertical direction of the fixed base 65, and supports the print paper P during printing. A print table 66 and a print head 67 facing the print paper P located on the print table 66 and ejecting ink to the print paper P for printing are provided. The print table 66 and the print head 67 constitute the print unit 4.

  The print table 66 is not configured to suck and hold the print paper P from below the print table 66 with a fan or the like, and does not have a suction hole or the like as shown in FIG. . At both ends of the print table 66 in the paper width direction (X direction shown in FIG. 6), a plurality of grooves 66a (6 on each side in this embodiment) extending in the paper transport direction (Y direction) are formed in the paper width direction. It is formed to line up at a predetermined interval. Each of the grooves 66a is provided corresponding to both positions in the width direction of the print paper P having various sizes. In each groove 66a, the ink ejected from the print head 67 is arranged in the width direction of the print paper P. An ink absorbing material 68 for absorbing the ink is fitted when it comes off from both ends (especially, it easily comes off when performing borderless printing). A concave portion 66b is formed in the central portion of the print table 66 in the paper width direction, corresponding to each position of three head units 67a described later, and 2 pieces of print paper P are placed in each concave portion 66b. An ink absorbing material 69 that absorbs ink preliminarily ejected (trial strike before printing) from each head unit 67a of the print head 67 when being printed in a row is fitted.

  In the present embodiment, as shown in FIG. 6, the print head 67 has a plurality of ink discharge nozzles 67b in the sub-scanning direction (paper transport direction (Y direction)) on the bottom surface (the surface facing the print table 66). Three head units 67a are provided so as to form a row, and these three head units 67a are arranged at intervals in the sub-scanning direction. Although only one nozzle row of each head unit 67a is shown in FIG. 6, actually, a plurality of nozzle rows are arranged in the paper width direction corresponding to each of a plurality of colors of ink. Further, the number of head units 67a is not necessarily three, but may be one or two, or may be four or more.

  The upper surface of the print head 67 is fixedly attached to a drive belt 70 for reciprocating the print head 67 in the main scanning direction (direction perpendicular to the paper surface of FIG. 1 (X direction shown in FIG. 6)). The drive belt 70 extends in the main scanning direction, and is wound around two pulleys 71 (only one is shown in FIG. 1) disposed at both ends thereof and rotatably supported on the upper portion of the fixed base 65. It is hung. The one pulley 71 is rotationally driven by an electric motor (not shown). A guide rail 72 extending in the main scanning direction along the drive belt 70 is attached and fixed to the upper portion of the fixed base 65, and the print head 67 is guided by the guide rail 72 while being driven by the drive belt 70. It reciprocates in the scanning direction. The print paper P on the print table 66 is intermittently (stepwise) conveyed in the sub-scanning direction by a constant unit conveyance amount by a conveyance roller 75 provided on the upstream side of the print table 66, and this intermittent conveyance is performed. At each stop of the print paper P at the time, the print head 67 is scanned one time in the main scanning direction (one-way operation or one-time operation), and the ink of each head unit 67a at each position in the main scanning direction during this scanning. Ink is ejected from the ejection nozzle 67b. That is, after one scan of the print head 67, the print paper P is transported by the unit transport amount, and then the print head 67 is scanned once again, and this operation is repeated to print a desired image. .

  The transport roller 75 is provided at the upstream end of the print unit U5 (that is, the upstream end of the downstream transport path and in the vicinity of the roller pair 41 (see FIG. 5) positioned at the delivery position). The print paper P delivered by the roller pair 41 positioned at the delivery position is received and conveyed to the printing unit 4. Like the feed roller 25 in the cutter unit U2, the transport roller 75 includes one drive roller 75a and two driven rollers 75b that sandwich the print paper P, and the two driven rollers 75b are one compression coil spring. 76 is pressed against the driving roller 75a. The drive roller 75a is rotated by an electric motor 77 via a transmission belt 78.

  As shown in FIG. 7, a guide having a guide surface 74 a for guiding the front end of the print paper P delivered from the movable conveyance unit u 40 located at the delivery position to the conveyance roller 75 on the upstream side of the conveyance roller 75. The member 74 is provided so as to cover the upstream side of the drive roller 75a and in a non-contact state with the drive roller 75a. The guide surface 74a is a curved surface that covers an obliquely upper portion of the rear side of the housing of the driving roller 75a, and the printed paper P sent from the rear side of the housing of the driving roller 75a is connected to the upstream driven roller 75b. It leads to the contact portion with the driving roller 75a. This guide surface 74a constitutes the upstream end of the downstream conveyance path that receives the print paper P.

  The height position of the sandwiched portion of the print paper P sandwiched by the transport roller 75 is higher than the upper surface of the print table 66, and the print paper P is wound around the drive roller 75a while being printed. The portion of the print base 66 that is wound around the drive roller 75a by the guide roller 79 that is supported from the upper end of the print table 66 so as to have a gap above the upstream end. In other words, the print paper P is conveyed in a state where the back surface of the print paper P is substantially in contact with the upper surface of the print table 66.

  On the other hand, on the downstream side of the printing table 66, two pairs of pressure bonding composed of driving and driven rollers 81a and 81b are provided to form a third transport path for discharging the printed paper P to the outside of the housing 1. The mold discharge rollers 81 are provided at intervals in the paper transport direction. The drive roller 81 a of each discharge roller 81 is driven simultaneously by the electric motor 82 via the transmission belt 83. The height of the downstream discharge roller 81 is higher than that of the upstream discharge roller 81, and the print paper P is lifted between the downstream discharge roller 81 and the upstream discharge roller 81 and the downstream side. A guide member 84 that leads to the discharge roller 81 is provided.

  As described above, since the print paper P is lifted to a position higher than the upper surface of the print table 66 on the upstream side and the downstream side of the print table 66, the portion of the print paper P on the print table 66 is the print table 66. It comes to be pressed against the top surface. Thereby, the flatness of the print paper P on the print table 66 is ensured. In particular, the printed paper P conveyed from the magazine housing unit 2 is curled by the winding rolls by the paper roll R so that the central portion in the length direction protrudes toward the printing surface with respect to both ends. Thus, even if the print paper P is curled, the flatness can be ensured without being attracted to the print table 66. In the present embodiment, as will be described later, the print paper P conveyed from the magazine accommodating portion 2 is corrected for the curl before being supplied to the print table 66, so that the flatness is further improved. Can do.

  The discharge tray 5 is provided on the front side of the discharge roller 81 outside the casing 1 and protrudes forward of the casing 1, and an auxiliary tray 5a is stored at the front end thereof. . When the length of the printed paper P to be discharged is longer than the length of the discharge tray 5, the auxiliary tray 5a can receive the long printed paper P by pulling it forward of the housing 1. ing.

  In the above configuration, since the conveyance path changes between the upstream conveyance path and the switchback unit U4 and between the switchback unit U4 and the downstream conveyance path, the print paper P is delivered. There is a need.

  First, the delivery of the print paper P between the upstream conveyance path (cutter unit U2) and the switchback unit U4 will be described.

  When the print paper P is delivered between the cutter unit U2 and the switchback unit U4 in the first conveyance path, the movable conveyance unit u40 is positioned at the first reception position as shown in FIG. Here, the print paper P conveyed by the first supply unit U1 is in a roll shape when viewed in the paper width direction by the winding roll of the paper roll R in the magazine housing unit 2 with the print surface facing upward. It is curled into a convex shape on the surface side facing the outside when it is wound (in this embodiment, on the print surface side). That is, in the section where the conveyance path between the cutter unit U2 and the switchback unit U4 is discontinuous, the front end portion of the print paper P fed out from the guide member 28 in the horizontal direction is the downstream end 28a of the guide member 28. It will be in the state where it hung down from. At this time, the bent portion 56b of the first support member 56 sends out the print paper P from the downstream end 28a of the guide member 28 of the cutter unit U2 as the downstream end of the upstream conveyance path when viewed from the print paper width direction. It is located at a position away from the print surface of the print paper P at the downstream end 28a by the predetermined distance from the straight line extending in the direction (horizontal direction). The predetermined distance is such that when the front end portion of the print paper P sent out from the downstream end 28a of the guide member 28 advances to the corresponding position of the first support member 56 in the horizontal direction, the front end portion is sent out. It is set to a distance away from a straight line extending in the vertical direction. By doing so, the front end of the print paper P sent out in the horizontal direction from the downstream end 28 a of the guide member 28 accurately reaches the first support member 56.

  Since the print paper P may hang downward due to its own weight depending on the paper quality, the predetermined distance may be adjusted in consideration of not only the curl amount of the print paper P but also its own weight.

  On the other hand, when the print paper P is delivered between the second supply unit U3 and the switchback unit U4 in the second transport path, the roller pair 41 is located at the second receiving position. The print paper P accommodated in the second supply unit U3 is a cut sheet and is not curled when viewed in the paper width direction. Therefore, in the second receiving position, the horizontal portion 56a of the first support member 56 is a contact portion between the feed roller 35 of the second supply unit U3 and the print paper P located at the top of the cassette housing portion 3. Located at approximately the same height. However, since the print paper P sent out by the feed roller 35 may hang downward due to its own weight, the bending portion 56b is a contact between the feed roller 35 and the print paper P positioned at the uppermost portion of the cassette housing portion 3. You may comprise so that it may be located below only the part of own weight rather than a contact part.

  Next, delivery of the print paper P between the switchback unit U4 and the downstream conveyance path (print unit U5) will be described.

  When the print paper P drawn from the magazine housing portion 2 is delivered between the switchback unit U4 and the print unit U5, the movable transport unit u40 is positioned at the delivery position as shown in FIGS. To do. Here, since the print paper P is conveyed to the print unit U5 with the print surface facing upward by the switchback unit U4, the print paper P sent out from the movable conveyance unit u40 is printed on the print surface as viewed in the paper width direction. It curls in a convex shape on the side, that is, on the upper side. That is, in the section where the conveyance path between the switchback unit U4 and the print unit U5 is discontinuous, the front end portion of the print paper P sent out from the roller pair 41 in the tangential direction of the contact portion 41c is It will be in the state hung down from the contact part 41c. Therefore, the front end portion of the print paper P sent out from the abutting portion 41c in the sending direction follows the curl shape of the print paper P as the print paper P advances, and the surface side opposite to the print surface from the sending direction. It will shift to. Therefore, at the delivery position, the rotation mechanism 90 causes the roller pair 41 to shift from the basic posture to the inclined posture in which the tangential direction of the contact portion 41c is inclined. Specifically, the feeding direction of the print paper P sent out from the contact portion 41c of the roller pair 41 (the tangential direction of the contact portion 41c of the roller pair 41, the one-dot chain line A in FIG. The side of the printed paper P that faces the outside when it is wound in a roll shape with respect to a straight line (a dashed line B in FIG. 7) connecting the portion 41c and the guide surface 74a of the guide member 74, that is, the print It is set to incline by a predetermined angle θ toward the surface side. The predetermined angle θ is set so that the front end of the printed paper P sent out in the sending direction reaches the guide surface 74a of the guide member 74 when it advances to the upstream end of the downstream conveyance path. Is done. Specifically, the predetermined angle θ is set based on the curl amount of the print paper P, the linear distance between the roller pair 41 and the guide surface 74a, and the like.

  By the way, the curl amount of the print paper P increases as the roll diameter of the roll in the magazine housing portion 2 decreases. That is, as the printing is executed, the curl amount of the print paper P increases. Therefore, the predetermined angle θ is adjusted according to the curl amount of the print paper P. The curl amount of the print paper P is calculated by integrating the print paper length of the order information in the receiving block 100 to calculate the use amount of the print paper P and from the use amount and the roll diameter of the print paper P at the beginning of setting. It can be calculated by deriving the current roll diameter of the print paper P. Then, the predetermined angle θ is determined from the calculated curl amount and the linear distance between the roller pair 41 and the guide surface 74a. The predetermined angle θ is adjusted by the rotation mechanism 90.

  On the other hand, when the print paper P drawn from the cassette housing portion 3 is delivered between the switchback unit U4 and the print unit U5, the movable transport unit u40 is positioned at the delivery position as shown in FIG. To do. Here, the print paper P conveyed to the print unit U5 with the print surface facing upward by the switchback unit U4 is a cut sheet and is not curled when viewed in the paper width direction. Therefore, the direction in which the print paper P is sent out from the contact portion 41 c of the roller pair 41 coincides with a straight line connecting the roller pair 41 and the guide surface 74 a of the guide member 74. That is, the tangential direction of the contact portion 41 c remains substantially horizontal and is not adjusted by the rotation mechanism 90. However, even a non-curled cut sheet may hang down due to its own weight, and therefore the tangential direction of the corresponding contact portion 41c may be inclined upward by the amount of its own weight.

  In the present embodiment, the transport rollers 75 of the switchback unit U4 and the print unit U5 are configured so that the paper roll R on the print paper P after the print paper P transported from the magazine housing unit 2 is cut by the cutter 26 is used. The curl straightening device which corrects the curl due to the curling wrinkles is constructed. In the case of the print paper P conveyed from the cassette housing unit 3, since the curl is not normally curled, the curl correction device does not operate.

  Specifically, the transport roller 75 of the print unit U5 has a role as a holding member that holds one end portion of the print paper P sent out by the roller pair 41 of the switchback unit U4 at the sending position. Reference numerals 41 respectively extend along the width direction of the print paper P held by the transport roller 75 and face each other while holding the vicinity of the one end of the print paper P therebetween. That is, when the transport roller 75 receives the print paper P sent out from the switchback unit U4 and holds the front end portion (rear end portion at the time of receiving), the operation is temporarily stopped and the front end portion is held. It is supposed to be. At this time, the roller pair 41 of the switchback unit U4 holds the vicinity of the front end portion of the print paper P held by the transport roller 75. Then, as shown in FIG. 8, in a state where the print paper P is held by the transport roller 75, the roller pair 41 holding the print paper P is moved in the opposite direction of the roller pair 41 by the moving mechanism of the switchback unit U4. Move to the drive roller 41a side. As a result, the print paper P is wound around the driven roller 41b on the upper side of the roller pair 41 in a state bent to the side opposite to the curl, and a portion between the transport roller 75 and the roller pair 41 of the print paper P A tension is applied to. That is, the printed paper P is curled by the winding roll of the paper roll R so that the central portion in the length direction protrudes toward the print surface side with respect to both end portions. By being wound around 41b, it is bent to the opposite side of the curl. For this purpose, the roller pair 41 is moved to the drive roller 41a side (that is, the lower side), which is the roller opposite to the print surface, so that the print paper P is wound around the driven roller 41b. As the roller pair 41 moves, the portion of the print paper P gripped by the roller pair 41 moves from the vicinity of the front end portion to the rear end portion side. As a result, the print paper P is squeezed by the roller pair 41 such that the side protruding from the curl (print surface side) is inside, and the curl is corrected. The conveyance roller 75 is configured to hold the print paper P in a state where the conveyance is stopped during the curl correction of the print paper P.

  Even if the rear end portion of the print paper P is detached from the roller pair 41, the roller pair 41 continues to move downward and returns to the first receiving position in order to receive the next print paper P. That is, the curl of the print paper P is corrected when the roller pair 41 moves from the sending position to the first receiving position. If the length of the print paper P is longer than the distance between the first receiving position and the sending position, the roller pair 41 is moved further downward than the first receiving position to omit the print paper P. The curl is corrected throughout and then returned to the first receiving position. Even when the print paper P is long as described above, the use of the space for hanging the print paper P downward as described above makes it possible to correct the curl over the entire print paper P without enlarging the casing 1 up and down. Can be done.

  As shown in FIG. 9, the inkjet printer has a microprocessor 101 (hereinafter referred to as a CPU), a conveyance control unit 102 connected to the CPU 101 via a data bus, a head control unit 103, and a print control. Unit 104, semiconductor memory RAM / ROM 105, communication interface 106, and first paper detection sensor 20 and second paper detection sensor 58 described above.

  The conveyance control unit 102 controls the operation of each of the units U1 to U5. The head control unit 103 controls the operation of the print head 67. The communication interface 106 is for transmitting and receiving information to and from the reception block 100. The print control unit 104 controls the print paper P to print image data based on the image data received from the receiving block 100 via the communication interface 106.

  Under the control of the conveyance control unit 102, the units U1 to U5 operate as follows.

  When printing is performed on the print paper P set in the magazine storage unit 2, first, the roll of the print paper P stored in the magazine storage unit 2 is determined based on the usage amount of the print paper P and the roll diameter immediately after setting. The diameter is obtained, and the curl amount of the printed paper P drawn from the diameter is calculated. Further, the movable conveyance unit u40 is moved by the moving mechanism, and the roller pair 41 is positioned at the first receiving position (see FIG. 1). Then, by operating the support roller 15 and supply roller 17 of the first supply unit U1 and the feed roller 25 of the cutter unit U2, the print paper P is pulled out of the magazine housing portion 2 and is positioned at the first receiving position. Transport to pair 41. At this time, the print paper P is curled in a convex shape on the print surface side with the print surface facing upward, and the front end portion of the print paper P fed from the guide member 28 hangs downward. Since the first support member 56 is positioned at the position where the front end portion hangs down, the front end portion of the print paper P sent out from the guide member 28 first comes into contact with the first support member, and then 1 is reliably guided to the roller pair 41 along the support member 56.

  The driving roller 41a of the roller pair 41 starts to drive when the front end of the print paper P is detected by the second paper detection sensor 58, and rotates (forward) in the counterclockwise direction in FIGS. The print paper P sent out from the unit U2 in the horizontal direction in the rearward direction is received and held. That is, the print paper P is sandwiched between the driving roller 41a and the driven roller 41b. The drive roller 41a continues to drive and draws the print paper P into the space space 12 on the rear side of the casing. Then, after the front end of the print paper P is detected by the second paper detection sensor 58, after the amount determined based on the order information is conveyed, the movable blade 26b of the cutter 26 is operated to cut the print paper P. The After this cutting, the driving roller 41a continues to drive, and stops when the rear end portion of the cut print paper P is gripped by the roller pair 41. At this stage, the print paper P gripped by the roller pair 41 is not on the upstream conveyance path, but is separated from the upstream conveyance path. The operations of the support roller 15 and the supply roller 17 of the first supply unit U1 and the feed roller 25 of the cutter unit U2 are stopped after the print paper P is cut.

  Subsequently, the drive belt 48 of the switchback unit U4 is operated, and the movable conveyance unit u40 moves upward so that the contact portion 41c of the roller pair 41 is substantially level with the guide surface 74a of the guide member 74 of the print unit U5. To do. Thus, the movable conveyance unit u40 stops at the delivery position (see FIG. 5). As a result, the print paper P is conveyed from the receiving position to the sending position in a state where it is separated from the upstream conveying path (cutter unit U2).

  Next, the predetermined angle θ is calculated based on the curl amount obtained when the print paper P is pulled out from the magazine housing unit 2. Then, as shown in FIG. 7, the electric motor 91 of the rotating mechanism 90 is operated to rotate the driven roller 41b about the center axis of the drive roller 41a, thereby tangentially locating the contact portion 41c of the roller pair 41 ( The one-dot chain line A) is inclined upward by an angle θ with respect to a straight line (one-dot chain line B) connecting the corresponding contact portion 41c and the guide surface 74a.

  Thereafter, the drive roller 41a of the roller pair 41 rotates (reverses) in the clockwise direction in FIG. 7, and the printed paper P after cutting is changed in the tangential direction of the contact portion 41c of the roller pair 41 with the corresponding contact portion 41c and the guide surface. The paper is fed forward to the transport roller 75 of the print unit U5 in a feed direction inclined upward by an angle θ with respect to a straight line connecting 74a. At this time, the print paper P is curled in a convex shape on the print surface side with the print surface facing upward, and the front end portion of the print paper P sent out from the roller pair 41 hangs downward. However, since the print paper P is sent in advance upward from the direction of the guide surface 74a of the guide member 74 as a delivery destination, the guide surface 74a is located at a position where the front end portion hangs down, and the print paper P The front end portion is reliably guided to the conveying roller 75 along the guide member 74.

  When the print paper P is sent out, the front end (rear end at the time of receipt) of the print paper P is detected by the second paper detection sensor 58, and by this detection, the transport roller 75 of the print unit U5 starts to operate. When the print paper P is sent by a predetermined amount (the amount until the front end of the print paper P is nipped by the transport roller 75), the operation of the transport roller 75 is temporarily stopped. As a result, the front end portion of the print paper P is held and held between the conveyance rollers 75. Thereafter, in this holding state, as described above, the roller pair 41 holding the print paper P is moved downward to correct the curl of the print paper P (see FIG. 8). At this time, the roller pair 41 returns to the basic posture. Note that the roller pair 41 may remain in an inclined posture, and the drive roller 41a of the roller pair 41 may continue to reverse or may be stopped. However, when the drive roller 41a is continuously rotated in the reverse direction, it is necessary to set the rotational speed and the moving speed of the roller pair 41 so that tension is applied to the print paper P. Eventually, the rear end portion of the print paper P is detached from the roller pair 41, but the roller pair 41 continues to move downward and returns to the first receiving position.

  After the roller pair 41 returns to the first receiving position or before returning to the first receiving position and after the rear end portion of the print paper P has passed the position where it deviates from the roller pair 41, the conveying roller 75 is actuated again. Then, the print paper P held at the time of curl correction is conveyed to the print table 66. The print head 67 is moved in the main scanning direction while being intermittently conveyed by the conveyance amount by the conveyance roller 75, and printing on the print table 66 is performed from the ink discharge nozzle 67 b of each head unit 67 a of the print head 67. Printing is performed by ejecting ink to the paper P.

  The printed print paper P is discharged to the outside of the housing 1 with the print surface facing upward by the discharge roller 81 and received by the discharge tray 5.

  On the other hand, when printing is performed on the print paper P set in the cassette housing unit 3, the movable transport unit u40 of the switchback unit U4 is positioned at the second receiving position (see FIG. 4). Then, by the operation of the feed roller 35 of the second supply unit U3, the print paper P is pulled out from the cassette housing portion 3 and conveyed to the roller pair 41 located at the second receiving position.

  Subsequently, after the roller pair 41 grips the rear end portion of the print paper P in the same manner as the print paper P pulled out from the magazine accommodating portion 2, the movable conveyance unit u40 moves upward and stops at the sending position. . As a result, the print paper P is conveyed from the receiving position to the sending position in a state where the print paper P is cut off from the upstream conveying path (second supply unit U3). Thereafter, the driving roller 41a of the roller pair 41 reverses and sends the print paper P to the transport roller 75 of the print unit U5 in the direction opposite to the moving direction when receiving the print paper P. At this time, the roller pair 41 sends the print paper P in a substantially horizontal direction while keeping the basic posture without inclining the tangential direction of the contact portion 41c.

  When the print paper P is delivered to the transport roller 75, the front end of the print paper P is detected by the second paper detection sensor 58, and the transport roller 75 of the print unit U5 starts operating by this detection. In the case of the print paper P set in the cassette housing unit 3, it is not necessary to correct the curl. Therefore, the transport roller 75 continues to operate without stopping, and the print paper P sent out from the switchback unit U4 is removed. Receiving and transporting to the printing stand 66 as it is. The movable transport unit u40 of the switchback unit U4 moves downward and returns to the second receiving position after the rear end of the print paper P is detected by the second paper detection sensor 58.

  Next, in the same manner as the print paper P drawn out from the magazine housing unit 2, printing is performed by moving the print head 67 in the main scanning direction while intermittently transporting the print paper P by the transport amount by the transport roller 75. . The printed print paper P is discharged by the discharge roller 81 to the outside of the housing 1 with the print surface facing upward, and is received by the discharge tray 5.

  Therefore, in the above-described embodiment, the switchback unit U4 sends the movable conveyance unit u40 having the roller pair 41 holding the print paper P by the moving mechanism in a state where the print paper P is separated from the upstream conveyance path. Since the print paper P is supplied onto the print table 66 in the downstream conveyance path, the degree of inclination of the print paper P in the width direction with respect to the print table 66 is reduced. It can be suppressed and the inclination degree is not increased. That is, if the print paper P is conveyed by the rollers, it becomes easy to skew even if errors in the roller shape or the like are slight. In particular, the print paper P is transferred from the magazine storage unit 2 to the print unit 4 using a large number of rollers. If the sheet P is continuously conveyed without being cut, it is influenced by the setting state of the print paper P in the magazine accommodating portion 2 and the number of rollers is large, so that the degree of inclination on the print table 66 is considerable. growing. Thus, when the print paper P is inclined on the print table 66, there arises a problem that the print quality is deteriorated. In particular, in an ink jet printer, the ink discharge nozzles 67b are arranged in a row in the sub-scanning direction (paper transport direction), and when the print paper P is inclined in the width direction, ink discharge is performed at both ends (upstream end and downstream end) of the nozzle row. The landing positions of the ink ejected by the nozzles 67b are greatly shifted from each other in the main scanning direction (paper width direction), and even a slight inclination affects the print quality. However, in the above embodiment, the switchback unit U4 is provided in the middle of the first conveyance path, receives the print paper P conveyed from the upstream conveyance path at the receiving position, and separates it from the upstream conveyance path. Since it is supplied to the printing stand 66 after being conveyed to the sending position in the state, the length of the conveyance path conveyed by the roller can be shortened by the amount corresponding to the conveyance of the print paper P by the switchback unit U4. The number of rollers can be reduced. In addition, since the regulating members for regulating the movement of the printed paper P in the width direction are provided at both ends of the first and second support members 56 and 57 of the switchback unit U4 in the width direction of the paper, Even if the inclination of the print paper P occurs on the road, the inclination is corrected by the switchback unit U 4, and the inclination of the print paper P in the print unit 4 is substantially influenced only by one transport roller 75. Become. Further, the print paper P on the print table 66 is not affected by the paper set state in the magazine housing unit 2. Further, since the switchback unit U4 is also provided in the middle of the second conveyance path, the width direction of the print paper in the print unit 4 is also the same as the long paper even in the case of cut paper. The inclination to can be reduced. Therefore, the inclination of the print paper P on the print table 66 can be reduced, and the print quality can be improved.

  Further, when the print paper P is fed in the print paper width direction at the abutting portion 41c of the roller pair 41 at the feed position, the corresponding contact portion 41c and the guide surface 74a of the guide member 74 (downstream conveyance) The print paper P is curled by the curl of the paper roll R in the magazine accommodating portion 2 by inclining the print paper P by a predetermined angle θ with respect to the straight line connecting the upstream end of the path). In addition, the print paper P can be easily transferred from the movable conveyance unit u40 to the print unit U5. Further, since the predetermined angle θ is adjusted based on the curl amount of the print paper P, the print paper P can be more easily transferred from the movable conveyance unit u40 to the print unit U5.

  Furthermore, in the above embodiment, in the switchback unit U4, since the gripping member that receives and grips the print paper P from the upstream conveyance path is configured by the roller pair 41, the front and back surfaces of the print paper P are damaged. And can be easily gripped. In addition, since the driving roller 41a of the roller pair 41 is driven by the electric motor 42, it is not necessary to separately provide a roller or the like for pulling in and feeding out the print paper P in addition to the roller pair 41, thereby reducing the cost. Can be planned.

  In the above embodiment, the print paper P can be guided from the upstream conveyance path to the downstream conveyance path with the print surface facing upward by the switchback unit U4, and the printing unit 4 (downstream conveyance path). Even if the paper set unit (upstream conveyance path) is arranged vertically, it is possible to convey the print paper P to the print unit U5 without bending it. As a result, curling is not promoted even with the printed paper P wound in a roll shape. Further, in combination with the configuration in which the print paper P is lifted to a position higher than the upper surface of the print table 66 on the upstream side and the downstream side of the print table 66, flatness can be ensured without providing a suction device. Alternatively, the flatness of the print paper P in the print unit 4 can be sufficiently secured with a simple and small suction device. Further, with respect to the first transport path, the upstream transport path and the first receiving position located on the upstream side of the switchback unit U4 are provided above the roll center of the print paper P set in the magazine housing unit 2. Therefore, coupled with the fact that the print paper P does not need to be bent and folded from the upstream conveyance path to the downstream conveyance path, the upstream conveyance path and the downstream conveyance path can be disposed close to each other, The inkjet printer can be made compact not only in the horizontal direction but also in the vertical direction (if the cassette housing part 3 is eliminated as will be described later, it can be made more compact). Therefore, the flatness of the print paper P in the print unit 4 can be ensured at a low cost while downsizing the entire inkjet printer. Further, in the case of the print paper P from the cassette housing portion 3, it is hardly bent, so that it does not curl and is not provided with a suction device or in the print portion 4 with a simple small suction device. The flatness of the printed paper can be sufficiently secured.

  Further, in the above-described embodiment, the curl of the print paper P from the magazine housing unit 2 is corrected, so that the flatness of the print paper P in the print unit 4 is ensured and the print quality is maintained at a high level. Can do.

  Furthermore, in the above embodiment, the magazine storage unit 2, the cassette storage unit 3 and the printing unit 4 are arranged so as to be arranged in the vertical direction, and the movable transport unit u40 of the switchback unit U4 corresponds to the vertical position thereof. Since it is configured to move in the direction, it is possible to shorten the length of the case 1 in the left-right direction and the front-rear direction by making the case 1 vertically long. Moreover, since the print paper P is moved in the front-rear direction of the casing, the length of the casing 1 in the left-right direction can be particularly shortened. Therefore, the printer can be easily installed in a narrow space.

  Further, if the cassette housing 3 is eliminated, the height of the housing 1 can be reduced, and a compact printer can be obtained as a whole. That is, in the configuration in which the switchback unit U4 is provided, the distance between the downstream end of the upstream conveyance path and the upstream end of the downstream conveyance path can be made as small as possible in terms of space. On the other hand, when the magazine storage unit 2 and the print unit 4 are arranged side by side in the vertical direction and the print paper P is continuously transported from the magazine storage unit 2 to the print unit 4 without being cut, the print paper P is abruptly moved. Since it cannot be bent, a certain amount of space in the up and down direction is required at the folded portion, and it is difficult to reduce the height of the housing 1 even if the cassette housing portion 3 is omitted. Therefore, the configuration provided with the switchback unit U4 is advantageous in that the height of the housing 1 can be reduced.

  In the above embodiment, the height positions of the contact portion 41c of the roller pair 41 of the movable transport unit u40 and the guide surface 74a of the guide member 74 are set to substantially the same height, but the present invention is not limited to this. is not. Even when the contact portion 41c and the guide surface 74a are at different height positions, the feeding direction of the print paper P is inclined by a predetermined angle θ from a straight line connecting the contact portion 41c and the guide surface 74a. The print paper P can be easily transferred to the print unit U5.

  In the above embodiment, the predetermined angle θ is adjusted by the curl amount of the print paper P, but may be a constant value without adjustment. In such a case, a print paper having a large curl amount is configured by increasing the area of the guide surface 74a of the guide member 74 of the print unit U5 or by decreasing the horizontal distance between the contact portion 41c of the roller pair 41 and the guide surface 74a. It is preferable that all the print paper P from P to the print paper P with a small curl amount can be received by the guide surface 74a.

  In the above-described embodiment, the contact portion 41c of the roller pair 41 of the movable transport unit u40 is configured to send out the print paper P and the first support member 56 receives the print paper P. However, the present invention is not limited thereto. It is not a thing. That is, a guide member that extends downstream from the contact portion 41c of the roller pair 41 may be provided, and the print paper P may be sent out from the print paper P from the downstream end of the guide member. Moreover, it is good also as a structure which does not provide the 1st support member 56 like the said embodiment. In such a case, the print paper P is directly received without the guide member by the contact portion 41c of the roller pair 41 or the drive roller 41a positioned below the roller pair 41.

  Furthermore, in the above-described embodiment, the feeding direction of the print paper P from the roller pair 41 is adjusted by the rotation mechanism 90, but the present invention is not limited to this. Even a mechanism other than the rotation mechanism 90 can be adopted as long as it can adjust the inclination in the tangential direction of the contact portion 41c of the roller pair 41.

  Furthermore, in the above embodiment, the paper transport device is configured by the switchback unit U4 having the function of switching back in addition to the function of transporting the print paper P. However, the print paper at the time of receiving the print paper P at the sending position is used. It may be a paper transport device (the other configuration is the same as that of the switchback unit U4) that feeds the downstream transport path in the same direction as the moving direction. However, in this case, since the downstream conveyance path is disposed on the opposite side of the upstream conveyance path with respect to the paper conveyance device, from the viewpoint of shortening the front-rear direction of the housing 1, the above embodiment is used. Thus, it is preferable to use the switchback unit U4 having the switchback function and the paper transport function.

  Furthermore, in the above-described embodiment, the moving mechanism of the switchback unit U4 moves the movable transport unit u40 in the vertical direction. However, the movement direction of the movable transport unit u40 is not limited to this. What is necessary is just to set suitably by positional relationship with an upstream conveyance path, a downstream conveyance path, etc. However, the arrangement as in the above embodiment is preferable because the entire inkjet printer can be made compact.

  Further, in the above embodiment, in the switchback unit U4, the gripping member that receives and grips the print paper P from the upstream conveyance path is configured by the roller pair 41. However, the switchback unit U4 grips the print paper P from both sides in the thickness direction. Any configuration may be used. In this case, a conveying means such as a roller for drawing and sending out the print paper P may be provided separately.

  Furthermore, in the above-described embodiment, the switchback unit U4 and the transport roller 75 constitute a curl correction device that corrects the curl of the print paper P, but this may be omitted.

  Moreover, in the said embodiment, although both the magazine accommodating part 2 and the cassette accommodating part 3 were provided, you may provide only the magazine accommodating part 2 and provide the magazine accommodating part 2 or the cassette accommodating part 3 in multiple numbers. You may do it.

  In addition, in the above embodiment, the ink jet printer of the present invention is applied to the one used in the photo print system. However, the print paper P (long paper or cut paper wound in a roll shape) is used as the paper set unit. The present invention can be applied to any printer as long as it is a printer that is transported from the printer to the printing unit 4.

  INDUSTRIAL APPLICABILITY The present invention is useful for a printer in which print paper set in a paper set unit is pulled out from the paper set unit and conveyed to the print unit, and is particularly useful for an ink jet printer used in a photographic print system.

It is the schematic seen from the housing | casing side which shows the structure of the inkjet printer which concerns on embodiment of this invention. It is the figure seen from the housing | casing side which shows the structure of a switchback unit. It is the figure seen from the housing | casing rear which shows the principal part of a switchback unit. FIG. 3 is a view corresponding to FIG. 1 showing a state when the movable transfer unit of the switchback unit is located at a second receiving position. FIG. 2 is a view corresponding to FIG. 1 and illustrating a state when the movable transfer unit of the switchback unit is located at a delivery position. It is a top view which shows a printing stand. FIG. 6 is a partially enlarged view showing a state when the movable conveyance unit of the switchback unit sends out the print paper at the sending position. FIG. 2 is a view corresponding to FIG. 1 showing a state in which curling of the printed paper is corrected. It is a block diagram which shows the structure of a control system.

Explanation of symbols

P Print paper R Paper roll U1 First supply unit (upstream transport path)
U2 cutter unit (upstream transport path)
U4 switchback unit (paper transport device)
U5 print unit (downstream transport path)
θ Predetermined angle 2 Magazine housing (paper set)
4 Print section 26 Cutter (cutting means)
74a Guide surface (upstream end of downstream conveyance path)

Claims (2)

A paper set unit in which a paper roll in which a long print paper is wound in a roll shape is set, a print unit that performs printing on a print surface of the print paper, and a print paper set in the paper set unit A printer comprising an upstream conveyance path for pulling out and conveying from a paper set unit, and a downstream conveyance path for conveying the print paper to the printing unit,
A cutting means provided in the upstream conveyance path, for cutting the print paper drawn out from the paper set unit into a predetermined length;
A paper transporting device provided between the upstream transporting path and the downstream transporting path, receiving and gripping the cut print paper, and feeding the gripped print paper to the downstream transport path;
The paper transport device is configured so that the paper transport device and the downstream side are viewed in the width direction of the print paper so that the front end of the print paper curled by the curl of the paper roll reaches the upstream end of the downstream transport path. A printer characterized in that print paper is sent out in a direction inclined by a predetermined angle with respect to a straight line connecting the upstream end of the transport path. The printer according to claim 1.
The printer according to claim 1, wherein the predetermined angle is adjusted according to a curl amount of the print paper.

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