JP2011121649A - Double-sided printing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide each of sheets of various sheet sizes with an appropriate curl, in an accumulation section of a double-sided printer. <P>SOLUTION: The double-sided printer includes: a first printing section printing on one surface of the sheet; the accumulation section into which the sheet printed on the one surface is carried, and which accumulates the plurality of sheets carried in; a second printing section printing on the other surface of the sheet carried out of the accumulation section. The accumulation section includes: a curl providing means 52 providing each of the sheets, serially carried into a carry-in position in the accumulation section, with a curl curving with the printed one surface inward, and having a first curl providing member 525a providing the sheet larger than or equal to a prescribed size with the curl, and a second curl providing member 525b providing the sheet smaller than the prescribed size with the curl; and a holding and transfer means 53 serially holding the lower end portion of each sheet serially carried into a carry-in position and provided with the curl, transferring the sheets to a carry-out position in the accumulation section in a state where lower end portions have a prescribed interval with each other, and serially releasing the holding of the lower end portion. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a duplex printing apparatus that performs printing on one side and the other side of a sheet, and more particularly to a duplex printing apparatus that stores a sheet on which one side is printed for a predetermined time and then transports and prints the other side.

  In recent years, it has been desired to reduce the amount of paper used for printing from the viewpoint of environmental problems and the like, and double-sided printing in which printing is performed on one side and the other side of paper is popular. As an example of this double-sided printing apparatus, a cylindrical first drum and a second drum each having a perforated stencil sheet wound around an outer peripheral surface are disposed adjacent to each other, and one side of the paper is printed with the first drum, There is known a double-sided stencil printing apparatus that conveys a sheet on which one side is printed and prints the other side with a second drum.

  In the case of such a double-sided printing apparatus, if printing on the other side is performed before the ink printed on one side is sufficiently dried, there is a risk that the paper will become dirty. On the other hand, in Patent Document 1, after sequentially stacking sheets of paper on which one side is printed on a loading table and storing them for a predetermined time, the sheets are transported in the stacked order and printed on the other side. A double-sided printing device that dries ink on a loading table has been proposed.

  Further, the storage surface for storing the paper on which one side is printed is provided with a holding mechanism for holding a plurality of papers on which one side is printed in a state of being stacked with a predetermined interval therebetween, so that the printed side, that is, the ink It is also conceivable that a plurality of sheets can be stored without bringing the surface to which the toner has been transferred into contact with other sheets, and rubbing or settling of the printing surface can be prevented.

JP-A-2005-29375

  In such a double-sided printing apparatus, the curling member is protruded at a position corresponding to the left and right lower end portions of the loaded paper, and the left and right lower end portions of the paper are pushed forward, whereby the printing is performed on the paper. The curl is curved with the inner surface facing inward, and when the holding mechanism holds the paper, the paper can be prevented from folding back, and the paper can be maintained stably with a predetermined gap between them. Can be considered.

  However, when such a double-sided printing apparatus is compatible with various paper sizes, the position corresponding to the left and right lower end portions of the paper carried into the storage unit is different for each paper size. There is a problem that an appropriate curl cannot be applied to all sheets of a size.

  SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a double-sided printing apparatus capable of imparting appropriate curls to papers of various paper sizes.

  The duplex printing apparatus of the present invention includes a first printing unit that prints on one side of a sheet, a storage unit that receives a sheet of paper on which one side is printed, stores a plurality of loaded sheets, and is unloaded from the storage unit. A second printing unit that prints on the other side of the paper, and the storage unit imparts a curl that is curved with the printed surface facing inward on the paper that is sequentially carried into the carry-in position in the storage unit A first curling member for imparting curl to a paper of a predetermined size or more, a curling means having a second curling member for imparting curl to a paper smaller than the predetermined size, and carry-in The lower end of each sheet that has been sequentially loaded into the position and has been curled is sequentially held, the sheet is moved to the unloading position in the storage unit with the respective lower ends spaced apart from each other, and the lower end is held. Hold movement to release sequentially And it is characterized in that it comprises a stage.

  In the above-described apparatus, the storage unit has a carry-in surface on which the paper moves when the paper is carried into the carry-in position, and the first and second curling members are respectively provided on the left and right sides of the paper at the carry-in position. The second curl protrudes from the carry-in surface toward the carry-out position at a position facing the lower end, pushes the left and right lower ends of the paper carried into the carry-in position toward the carry-out position, and imparts curl. The imparting member may be configured to be able to appear and retract from the carry-in surface.

  In addition, based on the size information acquisition unit that acquires the size information of the paper and the size information of the paper acquired by the size information acquisition unit, if the paper size is smaller than the predetermined size, the second curling member is loaded. It may be provided with a curling member driving means that protrudes from the surface and is immersed from the carry-in surface when the size of the paper is equal to or larger than a predetermined size.

Here, “based on the paper size information acquired by the size information acquisition means” is not limited to the case of directly using the paper size information acquired by the paper size information.
It also includes the case where it is used indirectly through another mechanism whose state changes according to the size information of the paper acquired by the size information acquisition means.

  In addition, when the second curling member is provided above the first curling member and the paper size is smaller than the predetermined size based on the paper size information acquired by the size information acquisition unit, the second curling member is equal to or larger than the predetermined size. Compared to the case, it may be provided with a position changing means for moving the holding and moving means upward.

  Further, the second curling member may be provided at the same height as the first curling member and on the inner side in the left-right direction of the first curling member.

  The curling member driving means includes a movable body that moves based on the size information of the paper, and the curling member driving means includes the movable body and a transmission mechanism that mechanically transmits the movement of the movable body to the second curling member. The second curling member may be caused to appear and disappear from the carry-in surface according to the movement of the body.

  Further, the movable body may be a sheet guiding means that moves in the left-right direction based on the sheet size information and guides the left and right ends of the sheet moving from the carry-in position to the carry-out position.

  According to the double-sided printing apparatus of the present invention, the storage unit imparts a curl that curves with the printed surface facing inward with respect to the sheets sequentially carried into the carry-in position in the storage unit. A curl applying unit having a first curling member for imparting curl to a paper of a size or larger and a second curling member for imparting curl to a paper having a size smaller than a predetermined size; And holding and moving means for sequentially holding the lower ends of the curled sheets and moving the sheets to the unloading position in the storage unit with the lower ends spaced apart from each other, thereby sequentially releasing the lower ends. The curl can be applied to the loaded paper using the curling member corresponding to the size of the paper among the first and second curling members. It is possible to impart the proper curl relative to the size of the paper.

  If the second curling member protrudes from the carry-in surface when the paper of a predetermined size or more moves on the carry-in surface and is carried into the carry-in position, the smooth carry-in processing of the paper and the execution of the curl application processing are hindered. There is a possibility. In the above apparatus, the storage unit has a carry-in surface on which the paper moves when the paper is carried into the carry-in position, and the first and second curling members are respectively arranged on the left and right sides of the paper at the carry-in position. At the position facing the lower end, it protrudes from the carry-in surface in the direction of the carry-out position, pushes the left and right lower ends of the paper carried into the carry-in position toward the carry-out position, and gives a curl. When the member is configured to be able to appear and retract from the carry-in surface, when the paper size is smaller than a predetermined size, the second curling member protrudes from the carry-in surface and is used for curling. If the size is equal to or larger than a predetermined size, it can be immersed from the carry-in surface so as not to cause the above problems.

  Specifically, based on the size information acquisition unit that acquires the size information of the paper and the size information of the paper acquired by the size information acquisition unit, the second curling is applied when the paper size is smaller than the predetermined size. Providing a second curl according to the size of the paper as described above by providing a curling member driving means for projecting the member from the carry-in surface and immersing the paper from the carry-in surface when the paper size is a predetermined size or more. The appearance of the member can be realized.

  A position where the apparatus moves the holding and moving means upward when the size of the paper is smaller than the predetermined size based on the paper size information acquired by the size information acquisition means compared to the case where the paper size is equal to or larger than the predetermined size. If there is a changing means, the upper and lower positions of the holding and moving means are changed so that the upper end of the paper stored in the storage section is the same height regardless of the size of the paper. Can be the same distance from the upper end of the paper in the storage unit to the second printing unit, even if the paper size is different, even if the paper size is different, the control to carry out the paper from the storage unit is shared It is possible to avoid the complication of the control. However, when the size of the paper is smaller than the predetermined size, the position of the holding and moving means moves upward, and the loaded paper stays higher than when it is larger than the predetermined size. There is a possibility that an appropriate curl cannot be imparted with the first curl imparting member provided below. Therefore, if the second curling member is provided above the first curling member, an appropriate curl is imparted to the paper smaller than the predetermined size using the second curling member. be able to.

  Also, for example, when holding the lower end of paper of any size at the same height, if the size of the paper is smaller than the predetermined size, the paper loaded in the left and right lower ends is equal to or larger than the predetermined size. Since it is present on the inner side in the left-right direction than at a certain time, there is a possibility that an appropriate curl cannot be imparted with the first curl imparting member provided on the outer side so as to be able to handle paper of a predetermined size or larger. Therefore, if the second curling member is located at the same height as the first curling member and is provided on the inner side in the left-right direction of the first curling member, for a paper smaller than a predetermined size, An appropriate curl can be imparted using the second curl imparting member.

  In addition, a movable body that moves based on the paper size information is provided, and the curling member driving means includes the movable body and a transmission mechanism that mechanically transmits the movement of the movable body to the second curling member. If the second curling member is to be retracted from the carry-in surface according to the movement of the body, it is necessary to separately provide a driving device such as a motor or a solenoid in order to cause the second curling member to protrude or retract. Therefore, the second curl applying member can be projected and raised according to the size of the paper as described above with a simple configuration.

Schematic configuration diagram of duplex printing device Side view showing the state of the storage section when paper of a predetermined size or more is carried in Perspective view showing the refeed fence Partial enlarged view of FIG. 2 is a perspective view of the main part of FIG. Side view showing the state of the reservoir when a paper smaller than a predetermined size is carried in 6 is a perspective view of the main part of FIG. Configuration diagram of peeling means

  Hereinafter, a double-sided printing apparatus 1 according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating a schematic configuration of the duplex printing apparatus 1, and FIG. 2 is a diagram illustrating a configuration of the storage unit 5 of the duplex printing apparatus 1.

  The duplex printing apparatus 1 is a duplex stencil printing apparatus, which feeds unprinted paper P1 and prints it on one side, stores the paper P2 after the one side printing for a predetermined time, refeeds the paper P2, and so on. Printing on the front side and discharging the paper P3 after printing on the other side.

  The duplex printing apparatus 1 includes a paper feeding unit 2 that feeds unprinted paper P1, a first printing unit 3 that prints on one side of the paper P1 fed from the paper feeding unit 2, and a first printing unit 3. A reverse conveyance unit 4 that reverses the paper P2 printed on one side, a storage unit 5 that stores the reversed paper P2 for a predetermined time, and a refeed unit 6 that refeeds the paper P2 stored in the storage unit 5 A second printing unit 7 that prints on the other side of the paper P2 that is re-fed from the re-feeding unit 6, and a paper discharge unit 8 that discharges the paper P3 printed on the other side by the second printing unit 7. It consists of.

  The paper feed unit 2 feeds unprinted paper P1 to the first printing unit 3, and is provided on the side surface of the apparatus main body 11. The paper feed unit 21 stacks the paper P1 and The paper feeding roller 22 that takes out the paper P1 one by one, the paper rolling roller 23, and a timing roller pair 24 that feeds the paper P1 into the first printing unit 3 are configured.

  The paper feed unit 2 takes out the paper P1 stacked on the paper feed table 21 by the paper feed roller 22 and the paper rolling roller 23, and sends it to the first printing unit 3 by the timing roller pair 24 at a predetermined timing.

  The apparatus body 11 of the duplex printing apparatus 1 recognizes the sheet size of the sheet P1 supplied to the sheet feeding unit 2 and transmits known size information SI to a control unit (not shown) in the apparatus body 11. An acquisition means 12 is incorporated. The size information SI is information for recognizing the size of the paper P1, is not limited to a specific size, and may be format information defined by an industrial standard such as JIS or ISO. In the present embodiment, the size information acquisition unit 12 recognizes whether the supplied paper P1 is A3, B4, A4, or B5, and transmits the recognition result as size information SI. It will be explained as being.

  The first printing unit 3 prints on one side of the paper P1, and includes a first plate cylinder 31. The first plate cylinder 31 has an ink-permeable peripheral wall 31a and is driven to rotate by a driving means (not shown). Inside the first plate cylinder 31, there are provided an ink supply roller 32 in contact with the inner peripheral surface of the peripheral wall 31a, a doctor roller 33 for supplying a predetermined amount of ink to the ink supply roller 32, and an ink bottle 34 filled with ink. It has been.

  A perforated stencil sheet M is wound around the outer peripheral surface of the first plate cylinder 31. A press roller 35 is provided below the first plate cylinder 31, and the press roller 35 moves so as to be close to and away from the first plate cylinder 31 so that the sheet P1 is sandwiched and printed with a predetermined pressing force. . On the lower right side of the first plate cylinder 31, a separation claw 36 for separating the paper P <b> 2 whose one side is printed by the first printing unit 3 from the base paper M is provided.

  When the sheet P1 is fed from the sheet feeding unit 2 at a predetermined timing, the first printing unit 3 sandwiches and conveys the sheet P1 between the first plate cylinder 31 and the press roller 35, and presses the sheet P1 against the base paper M. Print. The paper P2 on which one side is printed is separated from the base paper M by the separation claw 36.

  The reversing conveyance unit 4 conveys the sheet P2 on which one side is printed to the storage unit 5 and reverses the printed side so that the printed side is downward. Four pulleys 41 arranged along the surface, a plurality of holes formed on the surface, a conveyor belt 42 that is stretched around the outer periphery of the four pulleys 41 and moves as the pulleys 41 rotate, And a suction fan 43.

  The reversing conveyance unit 4 rotates the pulley 41 to move the conveyance belt 42 and generates suction force in a plurality of holes formed in the conveyance belt 42 by the suction fan 43 to suck and hold the sheet P2. Transport.

  The storage unit 5 carries the paper P2 printed on one side into the storage unit 5, stores the paper P2 for a predetermined time in order to dry it, and carries it out of the storage unit 5 for refeeding.

  As shown in FIG. 2, the storage unit 5 includes a support plate 5a that supports the paper P2 obliquely from below, and a pair of refeed fences 5b (paper guide means) that extend from both sides of the support plate 5a toward the carry-in surface 5d. And a cover plate 5c positioned obliquely upward with respect to the support plate 5a. Further, the storage unit 5 has the inner surface of the cover plate 5c as a carry-in surface 5d on which the paper P2 moves when it is carried in, and the inner surface of the support plate 5a as a carry-out surface 5e on which the paper P2 moves when it is carried out.

  FIG. 3 is a perspective view showing the refeed fence 5b. The refeed fence 5b guides the left and right ends of the paper P2 moving from the carry-in position toward the carry-out position, and its inner surface guides the movement of the paper P2 from the carry-in surface 5b to the carry-out surface 5e. It becomes.

  The storage unit 5 includes a fence position changing unit (not shown). The fence position changing unit is configured to determine the position of each refeed fence 5b based on the paper size information SI acquired by the size information acquiring unit 12. Is driven by a driving means (not shown) and moved in the direction of arrow B (left-right direction) in the drawing so that each of the paper P2 is always close to the left and right edges of the paper P2 by a predetermined distance in the left-right direction. The horizontal position of the paper fence 5b is adjusted. As shown in FIG. 4, the re-feeding fence 5b is regulated in position so that the leading end 5b ′ extending toward the carry-in surface 5d abuts on a transmission plate 526b of the S wing 525b described later. The movement of the refeed fence 5b is mechanically transmitted to the S wing 525b by sliding in the left-right direction while maintaining the contact state.

  Further, as shown in FIG. 2, the storage unit 5 is printed on the first transport means 51 that moves the paper P2 on the carry-in surface 5d and carries it to the carry-in position, and the paper P2 that is carried to the carry-in position. Size information acquisition, curling application means 52 for applying a curl that curves with the inner surface facing inward, holding movement means 53 for holding the lower end portion P2L of the paper P2 carried to the carry-in position and moving to the carry-out surface 5e side The position changing means 54 for changing the vertical position of the holding and moving means 53 based on the size information from the means 12, and the upper end P2U of the paper P2 carried to the carry-in position are peeled off, and the upper end P2U is again on the carry-in surface 5d Peeling means 55 for regulating the sheet P2 so as not to return to the second position, and second conveying means 56 for carrying out the paper P2 on the carry-out surface 5e from the storage unit 5.

  The first transport means 51 carries the paper P2 from the reversing unit 4 by moving it on the carry-in surface 5d to the carry-in position in the storage unit 5. Here, the carry-in position is a position below the storage unit 5 where the carried paper P2 can move, and is different for each paper size.

  As shown in FIG. 2, the first transport unit 51 is fixed to the cover plate 5c and is substantially sealed, and partitions the housing 511 into a suction chamber 511a on the transport upstream side and a suction chamber 511b on the transport downstream side. A partition plate 511c, two pulley pairs 512a and 512b arranged side by side with a predetermined interval in each suction chamber 511a and 511b, and spanned by each pulley pair 512a and 512b, are driven by a driving means (not shown) And annular belts 513a and 513b that move as the pulleys 512a and 512b rotate.

  Slots are formed in the cover plate 5c so that the annular belts 513a and 513b are exposed facing the suction chambers 511a and 511b, and each pulley pair 512a and 512b has an exposed surface of the annular belts 513a and 513b. The suction chambers 511a and 511b are arranged so as to be substantially flat with 5d. The annular belts 513a and 513b are formed with a plurality of through holes 513c and 513d as shown in FIG.

  The first transport means 51 is disposed outside the suction chambers 511a and 511b and the forced peeling claws 514c and 514d that can protrude from the loading surface 5d by rotating clockwise around the rotation shafts 514a and 514b. The suction fans 515a and 515b that discharge the air in the 511a and 511b to bring the suction chambers 511a and 511b into a negative pressure state are provided between the suction chambers 511a and 511b and the suction fans 515a and 515b. , 515b, intake shutters 516a, 516b, and suction shutters 517a, 517b for supplying outside air to return to atmospheric pressure in the suction chambers 511a, 511b in a negative pressure state.

  The first transport means 51 rotates the intake fans 515a and 515b in advance, opens the intake shutters 516a and 516b at a predetermined timing, closes the supply shutters 517a and 517b, and draws the air in the suction chambers 511a and 511b. Discharge to negative pressure. Outside air flows into the suction chambers 511a and 511b in the negative pressure state from the through holes 513c and 513d of the annular belts 513a and 513b facing the suction chambers 511a and 511b and exposed on the carry-in surface 5d, and the through holes 513c and 513d Generate suction force.

  The paper P2 carried into the storage unit 5 from the reversing unit 4 is sucked from the through holes 513c and 513d toward the annular belts 513a and 513b. Driving means (not shown) drives the pulleys 512a and 512b, whereby the paper P2 on which one side is printed moves on the exposed annular belts 513a and 513 and the substantially flat carry-in surface 5d.

  When the paper P2 is carried to the carry-in position in the storage unit 5, the intake shutters 516a and 516b are closed and the supply shutters 517a and 517b are opened to return the suction chambers 511a and 511b to atmospheric pressure, and then the forced peeling claw The paper P2 on the carry-in surface 5d is peeled by rotating the 514c and 514d clockwise around the rotation shafts 514a and 514b to contact the paper P2 and projecting onto the carry-in surface 5d. After a lapse of a predetermined time, the forced peeling claws 514c and 514d are rotated counterclockwise about the rotation shafts 514a and 514b, and retracted from the carry-in surface 5d to complete the peeling of the paper P2.

  The curl imparting means 52 imparts curl that is curved with the printed surface facing inward with respect to the paper P2 carried to the carry-in position. As shown in FIGS. 5 and 7, the curl imparting means 52 has a predetermined size or more. It has an M wing 525a (first curling member) for imparting curl to the paper, and an S wing 525b (second curling member) for imparting curl to a paper smaller than a predetermined size. Here, the size of the paper size means that if the paper size is large, both the vertical and horizontal sizes become large.

  Each wing 525a, 525b protrudes from the carry-in surface 5d toward the carry-out surface 5e at a position opposite to the left and right lower ends of the paper P2 at the carry-in position, and the left and right lower ends of the paper carried into the carry-in position. It is pushed out toward the carry-out position side to give a curl. In the present embodiment, the predetermined size is assumed to be B4.

  The M wing 525a gives curl to B4 size paper or more, for example, A3, B4 size paper, and as shown in FIG. 5, B4 size paper or more carried into the storage unit 5 And a guide plate 523a that can be rotated in the direction of arrow C about a rotation shaft 521a extending from the left and right outer sides to the inside and downward.

  The M wing 525a rotates the guide plate 523a around the fulcrum shaft 521a so that the guide plate 523a protrudes obliquely downward from the loading surface 5d before the paper P2 is carried into the storage unit 5. Let me.

  The S wing 525b provides curl to a paper size smaller than B4, for example, A4, B5 size paper, and as shown in FIG. 5, the S wing 525b is located in the storage unit 5 above the M wing 525a. A support plate 524b which is disposed at a position opposite to the left and right lower ends of the loaded paper smaller than the B4 size and which can rotate in the direction of arrow D about a rotation shaft 521b extending in the left-right direction; A transmission plate 526b that is pressed against the tip 5b 'of the paper fence 5b and mechanically transmits the movement of the refeed fence 5b to the support plate 524b, rotates integrally with the support plate 524b, and moves toward the unloading surface 5e. The guide plate 523b extends in a blade shape.

  The transmission plate 526b is provided so as to extend from the support plate 524b toward the carry-in surface 5dp, and the extension amount (extension width from the support plate 524b) is large on the outer side in the left-right direction, and on the inner side in the left-right direction. The support plate 524b is urged toward the unloading surface 5e by a spring mechanism (not shown) so that the front end surface 527b pushes the front end portion 5b 'of the refeed fence. It has been applied. The cover plate 5c is formed with a slot 5g so that the transmission plate 526b can come into contact with the refeed fence 5b, and a slot 5f is formed so that the guide plate 523b can protrude and retract from the carry-in surface 5d.

  The re-feeding fence 5b slides linearly in the left-right direction according to the paper size as described above, and the transmission plate 526b is moved to the re-feeding fence according to the left-right movement of the re-feeding fence 5b. The position on the front end surface 527b that contacts 5b changes, and the support plate 524b rotates in the direction of arrow D in accordance with the extension width of the transmission plate 526b at this position. As the support plate 524b rotates, the guide plate 523b also moves in and out of the carry-in surface 5d. In the present embodiment, the interval between the guide plates 523b in the left and right S wings 525b is set to 160 to 170 mm, and the maximum protruding amount of the guide plate 523b from the carry-in surface 5d is set to 7 mm or more.

  For example, when the paper size is smaller than B4, the refeed fence 5b slides inward in the left-right direction, and the leading end 5b ′ of the refeeding fence 5b hits the leading end surface 527b of the transmission plate 526b. The contact position slides inward in the left-right direction, and the extension width of the transmission plate 526b at the position where it abuts on the refeed fence 5b is reduced. Therefore, the guide plate 523b protrudes from the carry-in surface 5d by the spring mechanism described above. When the paper size is B4 or larger, the refeeding fence 5b slides outward in the left-right direction, and accordingly, the position where the leading end 5b ′ of the refeeding fence 5b abuts on the leading end surface 527b of the transmission plate 526b is located. The guide plate 523b is sunk from the carry-in surface 5d because the extension width of the transmission plate 526b at the position where it abuts against the refeed fence 5b increases.

  As described above, based on the paper size information SI from the information acquisition unit 12, the S wing 525b projects the guide plate 523b from the carry-in surface 5d when the paper size is smaller than B4, and the paper size is If it is greater than or equal to B4, it is immersed from the carry-in surface 5d.

  When the sheet P2 is sucked and transported to the loading position by the first transport means 51, the left and right lower ends of the sheet P2 are transported along the guide plate 523a or the guide plate 523b and forward of the center of the sheet P2. The lower end is inserted into the recess 535 of the holding and moving means 53 while being pushed out. As a result, the lower end of the sheet P2 is supported by the holding and moving means 53 in a state in which the curl curving with the printed one side inward is given.

  By giving the curl in this way, when the holding and moving means 53 described later supports the lower end of the paper P2 in a standing state and holds and moves the paper, it becomes difficult for the paper to be folded, and the standing state is maintained. Can be maintained.

  The holding and moving means 53 sequentially holds the lower end portions of the respective sheets P2 carried one by one in the carry-in position, and moves the sheets from the carry-in position to the carry-out position in the storage section with the respective lower end portions spaced apart from each other. The lower end is sequentially released, and a pair of pulleys 531 is disposed near the carry-in position and the other is disposed near the carry-out position, and the outer periphery of the pair of pulleys 531 is spanned. And a conveyor belt 532 that moves as the pulley 531 rotates by a driving means (not shown). In the present embodiment, description will be made assuming that the carry-in position side is upstream and the carry-out position side is downstream.

  A plurality of plate-like receiving claws 533 are erected on the entire outer peripheral surface of the annular belt 532 substantially vertically at a predetermined interval. Each of the receiving claws 533 includes an elastically deformable elastic claw 534 (in this embodiment, a leaf spring) that extends toward the adjacent receiving claw 533. The elastic claw 534 is pressed against the adjacent receiving claws 533 while being elastically deformed at a portion where the annular belt 532 is in a straight running state, that is, a portion where the adjacent receiving claws 533 are parallel to each other. Is in a curved running state, that is, in a portion where the gap between the catching claws 533 is widened, it is configured to be separated from the adjacent catching claws 533.

  When the paper P2 is carried to the carry-in position, the lower end portion of the paper P2 is inserted one by one into the recess 535 between the receiving claws 533. In the vicinity of the carry-in position, the annular belt 532 is in a curved running state, so that the gap between the receiving claws 533 is open, the gap between the receiving claws 533 and the elastic claws 534 is wider than the thickness of the paper P2, and the lower end of the paper P2 The portion can be received in the recess 535 between the receiving claws 533.

  After the paper P2 is carried into the recess 535 between the receiving claws 533, when the pulley 531 is rotated by a driving means (not shown), the annular belt 532 portion where the receiving pawl 533 that receives the paper P2 is located is in a straight running state, Since the claws 533 are parallel to each other, the lower end portion of the paper P2 is pressed toward the upstream receiving nail 533 by the elastic nail 534 in a state where the downstream elastic nail 534 is elastically deformed, and the upstream receiving nail It is held by 533 and the elastic claw 534 on the downstream side.

  When the pulley 531 further rotates and the downstream receiving claw 533 moves to the vicinity of the unloading position, the annular belt 532 is in a curved running state near the unloading position, so that the receiving claws 533 are opened, and the upstream receiving nail 533 The space between the elastic claw 534 on the downstream side is opened, and the holding of the lower end portion of the paper P2 is released. Depending on the moving time of the paper P2 from the carry-in surface 5d to the carry-out surface 5e, one printed surface of the paper P2 is dried.

  The position changing unit 54 is the position of the upper end P2T of the paper P2 that has been moved onto the carry-out surface 5e by the holding and moving unit 53 based on the size information SI acquired by the size information acquiring unit 12 and transmitted from the control unit (not shown). However, the position of the holding and moving means 53 in the vertical direction is changed so that the predetermined height position is obtained even when the paper sizes are different.

  The position changing unit 54 is stretched over a driving roller 541 driven by a driving unit (not shown), a driven roller 542 arranged at a predetermined interval in the vertical direction with respect to the driving roller 541, and the driving roller 541 and the driven roller 542. An annular belt 543 and a moving element 544 fixed to the annular belt 543 and connected to the holding and moving means 53 by a fixture (not shown).

  FIG. 6 is a configuration diagram of the storage unit 5 in which the position of the holding and moving unit 53 is changed in the vertical position by the position changing unit 54. Based on the size information SI from the size information acquisition unit 12, the position changing unit 54 is configured so that the upper end P2T of the sheet P2 moved onto the unloading surface 5e by the holding and moving unit 53 is at a predetermined position on the unloading surface 5e. Further, the height position of the holding and moving means 53 in the vertical direction is adjusted by driving the driving roller 541 in advance to move the moving element 544 in the direction of arrow A in the figure. Here, the amount of movement of the holding and moving means 53 in the vertical direction is determined according to the amount of movement in the carry-out direction of the upper end of the paper P2 on the carry-out surface 5e. Specifically, the holding and moving means is moved upward as the paper size is smaller. Thereby, the distance between the upper end of the paper P2 moved onto the carry-out surface 5e and the second printing unit 7 is constant regardless of the paper size, and the control at the time of carrying out the paper P2 can be made common.

  As shown in FIG. 8, the peeling means 55 peels the upper end portion P2U of the paper P2 carried to the carry-in position from the carry-in surface 5d, and restricts the upper end portion P2U from returning to the carry-in surface 5d again. .

  The peeling means 55 includes a drive shaft 551 disposed above the unloading surface 5e side of the reservoir 5, a cam 552 that is substantially semicircular and is fixed to the drive shaft 551 at the center of the semicircle, and the cam 552. A movable guide 553 that is rotatably connected to the cam 552 in the vicinity of the circumference thereof, and a first guide shaft 554 that is inserted into a slot 553a formed in the movable guide 553 and guides the path of the movable guide 553. Yes. The first guide shaft 554 is connected to one rotation shaft of a pickup roller pair 61 of the refeed unit 6 described later.

  Further, the peeling means 55 includes a rotating shaft 555 disposed above the loading surface 5d side of the storage unit 5, a peeling claw 556 fixedly supported by the rotating shaft 555, and a spring (not shown) fixed to the rotating shaft 555. , The lever 557 biased in the direction of arrow A in the figure, one link rotatably with the lever 557, the other abuts against the outer peripheral surface 552a of the cam 552, and a slot 558a formed in the link 558 And a second guide shaft 559 that guides the track of the link 558.

  The peeling means 55 rotates the drive shaft 551 in the direction of arrow B in the figure by the drive means (not shown) substantially simultaneously with the paper P2 being carried to the carry-in position. The cam 552 rotates with the rotation of the drive shaft 551, and the movable guide 553 rotatably connected to the cam 552 is guided and moved by the first guide shaft 554 inserted into the slot 553a.

  As the cam 552 rotates, the outer peripheral surface 552a of the cam 552 and the link 558 come into contact with each other, whereby the link 558 is guided to the second guide shaft 559 and moves in the direction of arrow C in the figure. As the link 558 moves, the lever 557 rotates around the rotation shaft 555 against the biasing direction. By the rotation of the rotation shaft 555, the peeling claw 556 rotates around the rotation shaft 555 in the direction of arrow D in the figure. That is, the peeling means 55 operates the movable guide 553 and the peeling claw 556 in synchronization with the rotation of the drive shaft 551.

  As the rotation shaft 555 rotates, the peeling claw 556 protrudes on the carry-in surface 5d, whereby the upper end portion P2U of the paper P2 is peeled from the carry-in surface 5d. After the movable guide 553 has moved in the substantially unloading direction, the movable guide 553 is moved upward in the vicinity of the loading surface 5d and substantially in the loading direction, whereby the movable guide 553 is peeled off by the peeling claw 556 and moved to the lower end P2U. Is entered between the carry-in surface 5d and the upper end P2U of the paper P2. This restricts the upper end portion P2U of the paper P2 from returning to the carry-in surface 5d again due to the thickness of the paper P2, curling by curling, and the airflow in the storage unit 5.

  By restricting the upper end portion P2U of the paper P2 from returning to the carry-in surface 5d again, it is possible to avoid a collision between the next paper P2 that is carried in and the upper end portion P2U of the paper P2 that returns to the carry-out surface 5e. When the rotation shaft 555 further rotates, the peeling claw 556 starts moving again toward the carry-in surface 5d, and the movable guide 553 that has moved up to the vicinity of the carry-in surface 5d moves downward on the carry-out surface 5e side. At this time, the movable guide 553 forcibly moves the upper end portion P2U of the paper P2 toward the carry-out surface 5e.

  The second conveying means 56 is for carrying out the paper P2 moved to the carrying-out position by the holding and moving means 53 from the storage section 5 to the refeeding section 6, and the housing 561 is fixed to the support plate 5a. Since the paper P2 does not have to be forcedly peeled off from the carry-out surface 5e, it is different from the first transport means 51 in that it does not have a peeling claw, but the other configuration is substantially the same as the first transport means 51. Detailed description is omitted.

  The second transporting unit 56 moves the paper P2 on the unloading surface 5e on the unloading surface 5e and unloads it from the storage unit 5 at a timing when a second plate cylinder 71 of the second printing unit 7 described later is at a predetermined position. . The operation of carrying out the paper P2 is substantially the same as that of the first transport means 51, and the detailed description thereof is omitted.

  The paper refeeding unit 6 refeeds the stored paper P2 to the second printing unit 7. The refeeding unit 6 picks up the paper P2 picked up from the storage unit 5 and the picked up paper P2. The timing roller pair 62 is fed to the second printing unit 7 at a predetermined timing. In the paper re-feeding unit 6, the pickup roller pair 61 sequentially picks up the paper P2 carried out from the second conveying means 56, and the timing roller pair 62 sends the picked up paper P2 to the second printing unit 7 at a predetermined timing. .

  The second printing unit 7 prints on the other surface of the stored paper P2. The configuration and operation of the second printing unit 7 are the same as those of the first printing unit 3, and detailed description thereof is omitted.

  The paper discharge unit 8 discharges the paper P3 on which the other side is printed. The paper discharge unit 81 that transports the paper P3 on which the other side is printed by the second printing unit 7; The paper discharge tray 82 is provided on the side and on which the paper P3 is stacked. The paper discharge conveying means 81 includes a driving roller 81a, a driven roller 81b, a conveying belt 81c, and a suction fan 81d. When the paper P3 printed on the other side by the second printing unit 7 is supplied onto the transport belt 81c, the paper discharge unit 8 sucks and transports the paper P3 by the suction fan 81d and stacks it on the paper discharge table 82.

  The overall operation of the duplex printing apparatus 1 will be described. The paper feeding unit 2 feeds an unprinted paper P1 to the first printing unit 3, and the first printing unit 3 prints on one side of the paper P1. The reversing unit 4 inverts the paper P2 and conveys it to the storage unit 5 so that one surface of the printed paper P2 faces downward.

  In the storage unit 5, the first transport unit 51 sucks and transports the sheet P2 to the carry-in position with one side of the sheet P2 facing down. At this time, the curl imparting means 52 imparts curl that is curved with the printed one side inward to the paper P2. Based on the paper size information SI from the information acquisition unit 12, the curling unit 52 projects the S wing from the carry-in surface 5d when the paper size is smaller than a predetermined size (for example, B4) in advance. If it is larger than the predetermined size, it is immersed from the carry-in surface 5d.

  The lower end portion P2L of the paper P2 carried into the carry-in position is held by the holding and moving means 53 and held and moved toward the carry-out surface 5e, and the upper end portion P2U of the paper P2 is peeled off from the carry-in surface 5d by the peeling means 55 In addition, it is restricted so as not to return to the carry-in surface 5d again. The holding and moving means 53 changes the position based on the paper size information SI from the information acquisition means 12 so that the height position of the paper P2 on the carry-out surface 5e is a predetermined height position regardless of the paper size in advance. The means 54 adjusts the position of the holding and moving means 53 in the height direction.

  The second conveying means 56 carries out the paper P2 on the carry-out surface 5e from the storage unit 5 to the refeeding unit 6, and the refeeding unit 6 refeeds the paper P2 to the second printing unit 7 at a predetermined timing. To do. The second printing unit 7 prints on the other side of the paper P2, and the paper discharge unit 8 discharges the paper P3 printed on the other side. Specifically, the duplex printing apparatus 1 can print one side and the other side of the paper P1 in a cycle of about 100 sheets per minute.

  As described above, according to the double-sided printing apparatus 1 according to the embodiment of the present invention, the storage unit 5 has the one surface printed on the sheets sequentially carried into the carry-in position in the storage unit 5 on the inner side. The curling is provided with an M wing 525a for curling a paper of a predetermined size or more and an S wing 525b for curling a paper smaller than the predetermined size. Means 52 and the lower end portion P2L of each paper sequentially carried into the carry-in position and provided with curl are sequentially held, and the paper is moved to the carry-out position in the storage portion with the respective lower end portions spaced apart from each other. Since the holding movement means 53 for sequentially releasing the holding of the lower end portion is provided, the curling member corresponding to the paper size of the loaded paper is appropriately selected and used from the M wing 525a and the S wing 525b. Therefore, it is possible to impart an appropriate curl to paper of various paper sizes.

  In the above embodiment, the case where the vertical position of the holding and moving means 53 is changed according to the paper size and the S wing is provided above the M wing has been described. However, the position of the holding and moving means is described above. The lower end of the loaded paper may be set at a predetermined height without being moved up and down, and the S wing may be provided at the same height as the M wing and on the inner side in the left-right direction of the M wing.

  Further, in the above embodiment, there is provided a transmission mechanism that mechanically transmits the movement of the refeed fence 5b to the S wing, and the case where the S wing is caused to appear and disappear from the carry-in surface according to the movement of the refeed fence 5b is described. However, not only the refeed fence 5b but various other mechanisms that move based on the paper size information may be used. For example, a transmission mechanism is provided that mechanically transmits the movement of the position changing means 54 that changes the vertical position of the holding and moving means 53 according to the paper size to the S wing, and the S wing according to the movement of the position changing means 54 May be made to appear and disappear from the carry-in surface.

  In the above-described embodiment, the case where the size information acquisition unit 12 automatically recognizes the paper size of the paper P1 supplied to the paper feeding unit 2 has been described. It is also possible to provide input means such as a touch panel for inputting, and receive the result of input by the input means. For example, a selection screen such as A3, B4, and A4 may be displayed on the touch panel, and the result of the user's selection for the selection screen may be received as information.

  In the present embodiment, the double-sided printing apparatus 1 has been described as a double-sided stencil printing apparatus. However, the present invention is not limited to this, and an inkjet printer or the like that can print on one side and the other side of the unprinted paper P1. It does not matter.

P1, P2, P3 Paper 1 Duplex printing device 3 First printing unit 5 Storage unit
5b Refeed fence
5d Loading surface
5e Unloading surface 7 Second printing section
12 Size information acquisition means
52 Curling means
52a S wing (first curling member)
52b M wing (second curling member)
53 Holding and moving means
54 Position change means

Claims (7)

A first printing section for printing on one side of the paper;
A storage unit for storing the plurality of sheets of paper that has been loaded with the paper on which the one side is printed;
A second printing unit that prints on the other surface of the paper carried out of the storage unit,
The reservoir is
A curl that is curved with the printed surface facing inward is applied to the paper sequentially carried into the carry-in position in the storage unit, and the curl is applied to paper of a predetermined size or more. A curling unit having a curling unit and a second curling unit that applies a curl to a sheet smaller than the predetermined size;
Sequentially holding the lower end of each paper sheet that has been sequentially carried into the carry-in position and the curl is applied, and moves the paper to a carry-out position in the storage unit with each lower end part spaced apart from each other; A double-sided printing apparatus comprising: a holding movement unit that sequentially releases the holding of the lower end portion. The storage unit has a carry-in surface on which the paper moves when the paper is carried into the carry-in position;
The first and second curl imparting members protrude in the direction of the carry-out position from the carry-in surface at positions facing the left and right lower ends of the paper at the carry-in position, respectively, and the paper carried into the carry-in position The left and right lower end portions are pushed out toward the carry-out position side to give a curl,
The double-sided printing apparatus according to claim 1, wherein the second curling member is configured to be able to appear and retract from the carry-in surface. Size information acquisition means for acquiring size information of the paper;
Based on the paper size information acquired by the size information acquisition means, when the size of the paper is smaller than the predetermined size, the second curling member is protruded from the carry-in surface, and the size of the paper is The double-sided printing apparatus according to claim 2, further comprising a curling member driving unit configured to be immersed from the carry-in surface when the size is equal to or larger than the predetermined size. The second curling member is provided above the first curling member;
Based on the paper size information acquired by the size information acquisition means, when the size of the paper is smaller than the predetermined size, the holding and moving means is moved upward as compared with the case where the size is equal to or larger than the predetermined size. The double-sided printing apparatus according to claim 3, further comprising a position changing unit.   The double-sided printing apparatus according to claim 3, wherein the second curling member is provided at the same height as the first curling member and on the inner side in the left-right direction of the first curling member. . A movable body that moves based on the size information of the paper;
The curling member driving means includes the movable body and a transmission mechanism that mechanically transmits the movement of the movable body to the second curling member, and the second curling member according to the movement of the movable body. 6. The double-sided printing apparatus according to claim 3, wherein the two-sided printing apparatus is configured to cause the machine to appear and disappear from the carry-in surface.   7. The sheet guide means for guiding the left and right edges of the sheet that moves in the left-right direction based on the size information of the sheet and moves from the carry-in position toward the carry-out position. Double-sided printing device.

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