JP2011110789A - Paper transferring mechanism, and printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal transfer printer which performs double-side printing while achieving a reduction in size and cost. <P>SOLUTION: The paper transferring mechanism 5 includes a feed roller 511 rotating in forward and reverse directions and arranged between a paper feeding part 2 which holds a paper S wound in a roll shape and a common printing part 3 which performs thermal transfer printing to the front surface Sa and the rear surface Sb of the paper S, a first cutter part 53 which is arranged between the paper feeding part 2 and the feed roller 511 and cuts the paper S to a predetermined size, a paper turning part 54 with a turning route 54S where the paper S, subjected to thermal transfer printing to the front surface Sa by the printing part 3 and cut to the predetermined size by the first cutter part 53, can be turned upside down, and a paper delivery guide part 55 which guides the paper S, turned upside down by the paper turning part 54 and subjected to thermal transfer printing to the rear surface Sb by the printing part 3, to a delivery part 4. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a paper transport mechanism and a printer.

  Recently, various printers capable of printing on both sides of paper have been developed. Printers that employ the thermal transfer method as a printing method can change the print density more finely than printers that employ printing methods such as the inkjet method and laser method. Expression is possible. Then, as a printer that can print on both sides of the paper using such a thermal transfer printing method, the front side print unit and the back side print unit are transported on a transport path formed between the paper feed unit and the paper discharge unit. An aspect in which the components are sequentially arranged along the direction is known (for example, see Patent Document 1).

JP-A-10-76713

  However, the above-described conventional mode has a problem in that the size and cost of the apparatus are increased because a print unit dedicated to front surface printing (front surface print unit) and a print unit dedicated to back surface printing are essential. Further, the above-described conventional mode also has a problem that replacement work and maintenance work of consumables and the like are individually required for the front surface print unit and the back surface print unit.

  The present invention has been made paying attention to such problems, and a main object of the present invention is to provide a paper transport mechanism and a printer capable of downsizing and cost reduction while allowing double-sided printing. It is in.

  That is, the paper transport mechanism according to the present invention passes a common print unit that performs print processing on the front and back surfaces of the paper supplied from a paper supply unit that can store paper wound in a roll shape. The paper feed unit is arranged between the paper feed unit and the print unit and sends out the paper toward the print unit, and the print direction in which the print unit can perform print processing. A feed roller unit that can be transported, a first cutter unit that is disposed between the paper feed unit and the feed roller unit, and that cuts the paper into a predetermined size. A paper reversing unit having a reversing path capable of reversing the paper cut to a predetermined size by one cutter unit and capable of conveying the reversed paper to the printing unit, and a paper reversing unit. It is characterized by a sheet that has been printed processed on the other surface by everted and printing unit Te is obtained by a discharge guide for guiding the sheet discharge unit.

  If it is such, it is possible to invert the sheet by cutting the roll-shaped sheet into a predetermined size by the first cutter unit, and passing the inside-out path in the sheet reversing unit. In the printing unit, the printing process is performed on either the front surface or the back surface of the paper (for example, the front surface), and after the paper is reversed, the same printing unit performs the printing process on the other surface (for example, the back surface). Can do. Furthermore, with the paper transport mechanism according to the present invention, the paper printed on both sides can be guided to the paper discharge unit by the paper discharge guide unit, and the paper discharge process can be performed smoothly and appropriately.

  With such a paper transport mechanism, printing is performed on the front and back surfaces of the paper by a common printing unit using a substantially common paper transport path in the process of transporting the paper between the paper feed unit and the paper discharge unit. Compared with the conventional mode, that is, the mode in which the print unit for the front side print and the print unit for the back side print are separately required, the overall mechanism can be reduced in size and cost. Can be planned.

  In particular, in the paper transport mechanism according to the present invention, when a paper reversing unit having a paper standby unit for slackening the paper and holding it in a state of holding the front end of the paper or the vicinity of the front end of the paper is applied, a plurality of print screens are set. Even when a long sheet of paper is left in the slack state in the paper standby section, the paper conveyed into the paper reversing section and the paper conveyed outside the paper reversing section can cross on the conveyance path. It can be avoided.

  Further, the paper discharge guide unit in the paper transport mechanism according to the present invention has a paper feed guide position where the paper fed from the paper feed unit can be transported toward the feed roller unit side, and the side not printed by the print unit. If the paper that has been subjected to the printing process can be switched between a paper discharge guide position that can be conveyed toward the paper discharge section, the paper discharge guide section is moved between the paper feed guide position and the paper discharge guide position. Between the paper feed unit and the paper discharge guide unit, or the paper discharge route that is the transport route between the paper discharge guide unit and the paper discharge unit. Any one of the paper paths can be selected, and the paper discharge guide portion can function as a branch point between the supply path and the paper discharge path.

  In addition, the paper transport mechanism according to the present invention is configured to cut the paper having a plurality of print screens between the paper discharge guide unit and the paper discharge unit at least at each print screen boundary. A cutter part can be provided. Accordingly, even when double-sided printing processing is performed on a plurality of print screens, the second cutter unit can appropriately cut each screen print before discharging.

  In addition, the printer of the present invention discharges paper that has been printed on both sides, a paper feed unit that can store paper wound in a roll, a common print unit that performs print processing on the front and back surfaces of the paper, and the like. And a paper transport mechanism configured as described above for transporting paper between the paper feed unit and the paper discharge unit via the printing unit.

  With such a printer, various effects obtained by the above-described paper transport mechanism can be exhibited, and the entire printer can be reduced in size and cost. The replacement work and the maintenance work may be performed, and the handleability is excellent as compared with the aspect in which the print section for front surface printing and the print section for back surface printing are individually provided. The present invention includes various printers such as a thermal transfer printing printer (thermal transfer printer), an inkjet printing printer (inkjet printer), or a printer employing a laser method (laser printer).

  According to the present invention, a paper transport mechanism that can perform double-sided printing by a single printing unit using a substantially common paper transport path when printing on the front and back surfaces, and can achieve downsizing and cost reduction, And a printer can be provided.

1 is a schematic diagram showing an internal configuration of a printer (thermal transfer printer) according to an embodiment of the present invention. FIG. 3 is a schematic diagram of one work process of the thermal transfer printer according to the embodiment. FIG. 3 is a schematic diagram showing an operation process of the thermal transfer printer according to the embodiment. FIG. 3 is a schematic diagram showing an operation process of the thermal transfer printer according to the embodiment. FIG. 3 is a schematic diagram showing an operation process of the thermal transfer printer according to the embodiment. FIG. 3 is a schematic diagram showing an operation process of the thermal transfer printer according to the embodiment. FIG. 3 is a schematic diagram showing an operation process of the thermal transfer printer according to the embodiment. FIG. 3 is a schematic diagram showing an operation process of the thermal transfer printer according to the embodiment. FIG. 3 is a schematic diagram showing an operation process of the thermal transfer printer according to the embodiment. FIG. 3 is a schematic diagram showing an operation process of the thermal transfer printer according to the embodiment. The schematic diagram which shows the modification of the paper inversion part in the embodiment. FIG. 11 is a work process diagram of the paper turnover portion in the modification. FIG. 11 is a work process diagram of the paper turnover portion in the modification.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  The printer 1 according to the present embodiment is a thermal transfer printer capable of performing sublimation print processing on the front surface Sa and the back surface Sb of the paper S by a common printing unit 3 as shown in FIG. It is. As shown in FIG. 1, the thermal transfer printer 1 includes a paper feed unit 2, a print unit 3 that performs sublimation print processing on the paper S supplied from the paper feed unit 2, a paper discharge unit 4, and a print unit. 3 is provided with a paper transport mechanism 5 for transporting the paper S between the paper feed unit 2 and the paper discharge unit 4 via 3. The thermal transfer printer 1 includes a paper feeding unit 2, a printing unit 3, and a paper transport mechanism 5 in a common housing (not shown). In the thermal transfer printer 1 according to the present embodiment, in the process of transporting the paper S from the paper feed unit 2 toward the paper discharge unit 4 by the paper transport mechanism 5, first, sublimation printing is performed on the surface Sa of the paper S by the print unit 3. After that, a sublimation printing process is performed on the back surface Sb of the paper S by the common printing unit 3.

  The paper feed unit 2 can accommodate the paper S wound around the roll shaft 21 in a roll shape.

  The printing unit 3 includes a thermal head 31, a platen roller 32 disposed at a position facing the thermal head 31, an ink ribbon 33, and ink that transports the ink ribbon 33 between the thermal head 31 and the platen roller 32. A ribbon transport mechanism 34 and a print control unit (not shown) for controlling the operation of the thermal head 31 and the like are provided.

  The thermal head 31 is a known one that prints on the paper S by generating heat from a heating element (not shown). In this embodiment, the thermal head 31 is set so as to be movable between a position where the paper S can be sandwiched between the platen roller 32 and a position where the thermal head 31 cannot be sandwiched by a head drive motor (not shown).

  The platen roller 32 can sandwich the paper S with the thermal head 31 and has a function of sequentially transporting the paper S while rotating. Accordingly, the platen roller 32 bears a part of the function of the paper transport mechanism 5. The platen roller 32 can rotate in forward and reverse directions in synchronization with a feed roller 511 described later.

  The ink ribbon 33 is obtained by applying, for example, yellow, magenta, and cyan inks to a long base film. The yellow, magenta, and cyan inks applied to the base film are formed using a dye that sublimes by heat.

  The ink ribbon transport mechanism 34 includes a supply-side ribbon core 341 around which an unused ink ribbon 33 (in which a base film is coated with ink) is wound, and a used ink ribbon 33 (part of ink from the base film or A take-up side ribbon core 342 that winds up, a supply-side ribbon guide 343 that guides the ink ribbon 33 unwound from the supply-side ribbon core 341 to the thermal head 31 side, and after passing through the thermal head 31 A take-up ribbon guide 344 for guiding the ink ribbon 33 peeled from the paper S to the take-up ribbon core 342 side is provided. The ink ribbon 33 wound around the supply-side ribbon core 341 is unwound to the thermal head 31 side by the supply-side ribbon guide 343 and the take-up side ribbon guide 344 and subjected to sublimation print processing, and then the take-up side. The ribbon core 342 is sequentially wound up. In the present embodiment, a set of the ink ribbon 33 and the ink ribbon transport mechanism 34 is unitized and configured to be detachable from the thermal head 31 and the platen roller 32.

  The print unit 3 including such units prints (forms) a color image on the front surface Sa and the back surface Sb of the paper S by sublimating each color ink of yellow, magenta, and cyan by the heat of the thermal head 31. Demonstrate the function. The printing unit 3 can perform gradation printing in which the print density level is changed by adjusting the temperature of the thermal head 31, and prints high-quality color images on the front surface Sa and the back surface Sb of the paper S. It is possible to print.

  The paper discharge unit 4 includes a paper discharge port (not shown) and a paper discharge tray 41 that receives paper discharged from the paper discharge port.

  The paper transport mechanism 5 transports the paper S stored in a roll shape in the paper feed unit 2 along a transport path formed between the paper feed unit 2 and the paper discharge unit 4. As shown in FIG. 1, the paper transport mechanism 5 is arranged on the paper feed unit 2 side with respect to the print unit 3, and feeds the paper S toward the print unit 3 and the print unit 3 with respect to the paper S. A feed roller unit 51 that can be conveyed in a print direction B that can be printed, a paper feed roller unit 52 that is disposed closer to the paper feed unit 2 than the feed roller unit 51, and a paper feed roller unit 52 and a feed roller unit 51 The first cutter unit 53 that is disposed between the first cutter unit 53 that cuts the sheet S into a predetermined size and the sheet S that has been printed on one side (the front surface Sa in the present embodiment) by the printing unit 3 are turned over to the printing unit 3. A sheet reversing unit 54 that can be transported, and a sheet S that has been reversed by the sheet reversing unit 54 and that has been printed on the other side (back side Sb in this embodiment) by the printing unit 3 is discharged. 4, a paper discharge roller portion 56 disposed between the paper discharge guide portion 55 and the paper discharge portion 4, and a space between the paper discharge guide portion 55 and the paper discharge portion 4. And a second cutter unit 57 that cuts at least the boundary of each print screen with respect to the paper S on which a plurality of print screens are set. In the thermal transfer printer 1 according to the present embodiment, the paper feed unit 2 and the paper discharge unit 4 are arranged on the same side (for example, the front side of the printer 1) with respect to the print unit 3, and the paper S with the paper turnover unit 54 as a turning point. The first print path, which is a transport path when performing print processing on one of the surfaces, and the second print path, which is a transport path when performing print processing on the other surface, are substantially common. The “feeding direction A” described above coincides with the direction from the paper discharge guide portion 55 toward the paper reversing portion 54, and the “print direction B” coincides with the direction from the paper reverse portion 54 toward the paper discharge guide portion 55.

  The feed roller unit 51 includes a feed roller 511 that can rotate forward and backward in a first transport direction a in which the paper S can be transported in the feed-out direction A and a second transport direction b in which the paper S can be transported in the print direction B. And a pinch roller 512 that rotates in the forward and reverse directions following the rotation of the feed roller 511 while in direct contact with the sheet 511 or indirectly through the sheet S.

  The paper feed roller section 52 includes a paper feed roller 521 that can rotate forward and backward in a first transport direction c that can transport the paper S in the feed-out direction A and a second transport direction d that can transport the paper S in the print direction B; A pinch roller 522 that rotates in the forward and reverse directions following the rotation of the paper feed roller 521 while in direct contact with the paper feed roller 521 or indirectly through the paper S is provided.

  The first cutter unit 53 is configured by using a pair of cutter main bodies that are arranged to face each other so as to sandwich the paper S.

  The paper reversing unit 54 includes a reversing path forming unit 541 that forms a reversing path 54S that is a path for reversing the paper S, a start-end-side feed roller unit 542 that is disposed at or near the start end of the reversing path 54S, and the end of the reversing path 54S Also, a terminal-side feed roller portion 543 arranged near the end, and a carry-in / out portion that carries the paper S in and out of the reverse path 54S by being arranged closer to the print unit 3 than the start-side feed roller portion 542 and the end-side feed roller portion 543. A feed roller unit 544 and a paper leading edge detection unit 545 disposed in the vicinity of the terminal side feed roller unit 543 are provided.

  The inside-out path forming unit 541 has a guide roller 541a and a guide rail 541b that face each other with a predetermined gap therebetween and can function as the inside-out path 54S of the paper S. The guide roller 541a has a circular or substantially circular outer edge and cannot rotate. On the other hand, the guide rail 541b has a partial arc shape, is disposed concentrically with the guide roller 541a, and forms a partial arc-shaped reverse path 54S between the guide roller 541a and the guide roller proximity position (Q). And a guide roller retracting position (R) that forms a reverse path 54S that can be retracted from the guide roller 541a and loosen the paper S between the guide roller 541a and can be moved (switchable). Is. In this embodiment, the guide rail 541b is located between the guide roller proximity position (Q) and the guide roller retracted position (R) with one end portion of the guide rail 541b (the end portion on the reverse side of the reverse path 54S) as a fulcrum. It is configured to rotate and move. Switching between the guide roller proximity position (Q) and the guide roller retracted position (R) can be performed by a guide rail drive motor (not shown).

  The start-end-side feed roller unit 542 transports the sheet S from the start end side of the reverse path 54S into the reverse path 54S, and the sheet S from the start end side of the reverse path 54S toward the print unit 3. A start-end-side feed roller 542a that can rotate forward and backward in the second conveying direction f, and a rotation of the start-end-side feed roller 542a in a state of being in direct contact with the start-end-side feed roller 542a directly or indirectly via the paper S. And a pinch roller 542b that rotates in the forward and reverse directions.

  The end-side feed roller unit 543 transports the paper S from the terminal side of the reverse path 54S toward the print unit 3, and transports the paper S from the terminal side of the reverse path 54S into the reverse path 54S. The end-side feed roller 543a that can rotate forward and backward in the possible second transport direction h, and the end-side feed roller 543a are driven by the rotation of the end-side feed roller 543a in a state of being in direct contact with the end-side feed roller 543a directly or indirectly via the paper S. And a pinch roller 543b that rotates in the forward and reverse directions.

  The carry-in / out feed roller section 544 has a first transport direction i in which the paper S can be transported toward the reverse path 54S (can be transported), and a second that can transport the paper S toward the print section 3 (can be transported out). A carry-in / out feed roller 544a that can rotate forward and backward in the transport direction j, and a rotation of the carry-in / out feed roller 544a in contact with the carry-in / out feed roller 544a directly or indirectly via the paper S And a pinch roller 544b that rotates in the forward and reverse directions.

  The first transport direction e of the start-side feed roller 542a, the second transport direction g of the end-side feed roller 543a, and the second transport direction j of the carry-in / out feed roller 544a are all the same direction, and their rotational directions. Is the same direction as the second conveying direction b of the feed roller 511. Further, the second transport direction f of the start side feed roller 542a, the second transport direction h of the end side feed roller 543a, and the first transport direction i of the carry-in / out feed roller 544a are all the same direction, and their rotational directions. Is the same direction as the first transport direction a of the feed roller 511.

  The paper leading edge detection unit 545 is configured by, for example, a detection sensor, and in the present embodiment, the paper leading edge detection unit 545 is disposed slightly closer to the printing unit 3 side than the terminal side feeding roller unit 543.

  The paper discharge guide portion 55 that guides the paper S to the paper discharge portion 4 is disposed between the feed roller portion 51 and the paper feed roller portion 52. In the present embodiment, the paper discharge guide portion 55 has a paper discharge guide surface 551 that can come into contact with the paper S, and the paper discharge guide surface 551 coincides with or substantially coincides with a straight line connecting the paper feed roller 521 and the feed roller 511. The sheet feed guide position (S) can be rotated between the matched sheet feed guide position (S) and the sheet discharge guide position (T) in which the sheet discharge guide surface 551 is retracted from a straight line connecting the sheet feed roller 521 and the feed roller 511. A roughly lever-shaped one is applied. Note that switching between the paper feed guide position (S) and the paper discharge guide position (T) can be performed by a guide drive motor (not shown).

  The paper discharge roller unit 56 includes a paper discharge roller 561 and a pinch roller 562 that rotates following the rotation of the paper discharge roller 561 in a state where it is in direct contact with the paper discharge roller 561 or indirectly through the paper S. It is a thing.

  The 2nd cutter part 57 is comprised using a pair of cutter main body arrange | positioned facing so that the paper S can be pinched | interposed.

  Next, the operation and action of the thermal transfer printer 1 according to the present embodiment, in particular, the operation and action of the paper transport mechanism 5 will be described with reference to FIGS.

  First, the paper transport mechanism 5 rotates the feed roller 511 and the paper feed roller in the first transport direction (the first transport direction a and the first transport direction c) and winds them in a roll shape in the paper feed unit 2. The paper S passes between the paper feed roller 521 and the pinch roller 522 and is sequentially conveyed to the feed roller unit 51 and the print unit 3. At this time, the paper discharge guide section 55 is set to the paper feed guide position (S). In the printer 1 according to the present embodiment, the thermal head of the printing unit 3 is used when the paper S is conveyed in the feeding direction A and the printing direction B along the conveyance path without performing the sublimation printing process by the printing unit 3. 31 is kept in a position where the sheet S cannot be sandwiched between the platen roller 32 and the sheet S is smoothly conveyed. In FIGS. 2 to 10, the thermal head 31 is disposed between the platen roller 32 and the thermal head 31. Shows a state in which the sheet S is moved to a position where the sheet S can be sandwiched.

  The sheet transport mechanism 5 according to the present embodiment has a feed roller 511 that rotates in the first transport direction a and the number of screens (in the illustrated example) on which print processing is performed by the platen roller 32 that rotates in the same direction as the feed roller 511. 3 sheets of print screen PA, print screen PB, and print screen PC) and the paper S is added by an amount corresponding to the length corresponding to the back side print gripping Sc formed on the front end St side of the paper S. The paper is transported downstream from the print unit 3 (the paper reversing unit 54 side), and the front end St side region of the paper S is temporarily held by the paper reversing unit 54 (see FIGS. 2 and 3). Specifically, the guide rail 541b is set at the guide roller proximity position (Q), and the carry-in / out feed roller 544a, the start-end side feed roller 542a, and the end-side feed roller 543a are set in the first transport direction (first The paper S is rotated sequentially in the transport direction i, the first transport direction e, and the first transport direction g), and sequentially transports the sheets S to a partially arcuate reverse path 54S formed between the guide rail 541b and the guide roller 541a ( (See FIG. 2). In the paper transport mechanism 5 according to the present embodiment, the leading edge St of the paper S passes through the trailing-side feed roller 543a and reaches the paper leading edge detection unit 545, and the leading edge St of the paper S is moved by the paper leading edge detection unit 545. When detected, the guide rail 541b is moved from the guide roller proximity position (Q) to the guide roller retracted position (R) to open the reverse path 54S downward and stop the rotation of the terminal-side feed roller 543a. In the state where the leading edge St or the vicinity of the leading edge St is sandwiched and held between the trailing-side feeding roller 543a and the pinch roller 543b, the carry-in / out feeding roller 544a and the leading-end feeding roller 542a continue to be in the first transport direction, respectively. By rotating in the first conveyance direction i and the first conveyance direction e, the sheet is sent to the paper turnover unit 54 thereafter. Slackens the sheet S (see FIG. 3). That is, the paper reversing unit 54 according to the present embodiment has a function as a paper standby unit that loosens and waits for the paper S while holding the paper leading end St or the vicinity of the paper leading end St. Here, the dimension (grip dimension) of the back surface printing gripping margin Sc secured in the area near the paper leading edge St corresponds to the center-to-center distance between the feed roller 511 and the platen roller 32. Further, among a plurality of print screens on the paper S, a predetermined area continuous with the print screen (print screen PA in the illustrated example) on the terminal side (the anti-tip side) of the paper S functions as the front surface print grip margin Sd. The size (grip size) of the front surface printing grip margin Sd is the same as the back surface printing grip margin Sc and corresponds to the center-to-center distance between the feed roller 511 and the platen roller 32 (see FIG. 3). 3, 7, and 8 schematically show the paper S viewed from the thermal head 31 side in the lower area of the paper surface in order to show the relative positional relationship between the paper transport mechanism 5 and the paper S. .

  Subsequently, in the thermal transfer printer 1 according to the present embodiment, both ends or the vicinity of both ends of the surface printing grip allowance Sd are sandwiched between the feed roller 511 and the pinch roller 512 and between the platen roller 32 and the thermal head 31, respectively. At the time (see FIG. 3), the feed roller 511 is rotated in the second conveying direction b, and the platen roller 32 is also rotated in the same direction as the feed roller 511. The rollers 544a, the start side feed roller 542a, and the end side feed roller 543a are also rotated in the second transport direction (second transport direction j, second transport direction f, and second transport direction h), respectively. As a result, the paper transport mechanism 5 can transport the paper S in the print direction B (see FIG. 4). At this time, the sheet S that has been waiting in the state of being slackened by the sheet reversing unit 54 is also conveyed in the printing direction B from the starting end side of the reversing path 54S through the carry-in / out feeding roller unit 544. Accordingly, the sheet S conveyed from the start end side of the reverse path 54S toward the printing unit 3 is in a state where the surface Sa faces the thermal head 31, and the printer 1 displays each print screen on the surface Sa of the sheet S (FIG. In the illustrated example, the print unit 3 performs sublimation print processing on the print screen PA, print screen PB, and print screen PC). The printer 1 according to the present embodiment sequentially performs print processing on the surface Sa of the paper S from the print screen (print screen PA in the illustrated example) on the paper end side (anti-front end side) of all print screens. The printer 1 rotates the paper feed roller 521 and the roll shaft 21 of the paper feed unit 2 in the same direction in synchronization with the feed roller 511 when the print unit 3 performs a printing process on the surface Sa of the paper S. The sheet S on which the printing process has been performed is conveyed to the paper feed unit 2 side, and when the sheet S is long, the region on the opposite end side of the sheet S on which the printing process has been performed is wound around the roll shaft 21. ing.

  After performing the printing process on the entire print screen on the front surface Sa of the paper S, the paper transport mechanism 5 rotates the feed roller 511 in the first transport direction a and the platen roller 32 in the same direction as the feed roller 511. Further, the rollers (the carry-in / out feed roller 544a, the start-end-side feed roller 542a, and the end-side-feed roller 543a) of the paper turnover portion 54 are also in the first transport direction (the first transport direction i, the first transport direction e, and the first transport direction). Rotate in one transport direction g). Thereby, the paper transport mechanism 5 can transport the paper S in the feed-out direction A. Then, the paper S is transported to the paper reversing unit 54 by the paper transporting mechanism 5, and the paper reversing unit 54 is made to stand by according to the procedure described above. At this time, the back surface Sb of the paper S faces (contacts) the outer peripheral surface of the guide roller 541a, and the front surface Sa subjected to the printing process cannot directly contact the outer peripheral surface of the guide roller 541a. This avoids problems that may occur when the surface Sa subjected to the printing process is in direct contact with the outer peripheral surface of the guide roller 541a, that is, problems such as bleeding of ink immediately after being transferred to the surface Sa of the paper S. it can. Next, the boundary line between the print screen (print screen PA in the illustrated example) on the paper end side of the print screen on the front surface Sa of the paper S and the grip margin Sd for the front print is the first cutter unit. When reaching 53, the first cutter unit 53 cuts the paper S at the boundary line between the print screen PA and the surface print grip allowance Sd.

  The printer 1 according to the present embodiment rewinds the unprinted area of the cut sheet S with the front-side print gripping margin Sd as the leading end to the sheet feeding unit 2 (specifically, the sheet feeding roller 521 is moved to the first position). 2 Rotate in the transport direction d, and rotate the roller shaft 21 of the paper feed unit 2 in the same direction as the paper feed roller 521 to rewind until the front end of the front-side print gripping margin Sd has passed through the paper discharge guide unit 55. ) On the other hand, the paper S with the back side print gripping Sc as the leading edge is transported in the feeding direction A, and the paper S is transported to the paper reversing unit 54 by the paper transporting mechanism 5. Wait in the relaxed state (see FIG. 5). Note that, as described above, when the sheet S is made to wait in the state where the sheet S is slackened by the sheet reversing unit 54, the terminal-side feed roller 543a in the sheet reversing unit 54 rotates with the sheet leading end St held between the pinch roller 543b. Have stopped without. The printer 1 according to the present embodiment rotates the terminal-side feed roller 543a in the first transport direction g when the end of the sheet passes the carry-in / out feed roller 544a (see FIG. 6), By rotating the roller 544a and the feed roller 511 in the second transport direction (second transport direction j, second transport direction b), the sheet S is directed from the end of the reverse path 54S toward the printing unit 3, that is, in the print direction B. Transport to. The sheet S that is transported in the print direction B through the reverse path 54S is in a state where the front and back are reversed as compared with the state before passing through the reverse path 54S (see FIG. 7).

  Then, the printer 1 according to the present embodiment has a thermal head when the rear surface printing grip Sc secured on the leading end St side of the paper S is reached between the feed roller 511 and the pinch roller 512 (see FIG. 7). 31 is moved to a position where the paper S can be sandwiched between the platen roller 32 and each print screen on the back surface Sb of the paper S (in the illustrated example, the print screen PA ′, which is the back surface of the print screen PA, and the print screen PB). Sublimation print processing is performed by the printing unit 3 on the print screen PB ′ which is the back surface and the print screen PC ′ which is the back surface of the print screen PC. At this time, the print processing for the back surface Sb of the paper S is sequentially performed from the print screen (print screen PC ′ in the illustrated example) on the front end St of the paper among all print screens. Further, the paper discharge guide portion 55 is switched from the paper feed guide position (S) to the paper discharge guide position (T) before the time point when the printing process is performed on the back surface Sb of the paper S (see FIG. 7). . As a result, the sheet S on which the print processing has been performed on the back surface Sb is guided by the sheet discharge guide unit 55 and conveyed toward the sheet discharge unit 4 (see FIG. 8), and between the sheet discharge roller 561 and the pinch roller 562. The sheet passes through the sheet and is discharged to the sheet discharge tray 41 (see FIG. 9). In the thermal transfer printer 1 according to the present embodiment, the second cutter unit 57 provided between the paper discharge roller 561 and the paper discharge tray 41 causes the boundary between the back surface print gripping cost Sc and the print screen, and the print screen. The boundary between them is cut and discharged to a paper discharge tray 41 as a cut sheet of a predetermined size (see FIG. 10).

  In the next print process, the area that has functioned as the front surface print grip margin Sd during the previous print process functions as the rear surface print grip margin Sc.

  As described above, the paper transport mechanism 5 according to the present embodiment is configured so that the paper S cut into a predetermined size by the first cutter unit 53 provided between the paper feeding unit 2 and the feed roller unit 51 is fed to the paper reversing unit 54. The paper can be reversed by passing through the reverse path 54S. The printing unit 3 performs a printing process on the surface Sa of the paper S before the paper S is reversed, and the same printing unit 3 after the paper S is reversed. Thus, the printing process can be performed on the back surface Sb of the paper S. Therefore, by applying the paper transport mechanism 5 as described above, the front surface Sa and the back surface of the paper S using the common print unit 3 in the process of transporting the paper S between the paper feed unit 2 and the paper discharge unit 4. The thermal transfer printing process can be performed on each Sb, and the entire sheet transport mechanism 5 is compared with the conventional mode, that is, the mode in which the front side print unit and the back side print unit are individually required. As a result, the entire printer 1 can be reduced in size and cost. In addition, since the transport path of the paper S is almost shared between the front surface printing and the back surface printing, this also contributes to the downsizing of the paper transport mechanism 5 and the printer 1. Furthermore, the paper transport mechanism 5 according to the present embodiment can guide the paper S that is turned upside down by the paper turnover unit 54 and printed on the back surface Sb by the print unit 3 to the paper discharge unit 4 by the paper discharge guide unit 55. The paper discharge process can be performed smoothly and appropriately.

  In addition, since the paper reversing unit 54 in the paper transport mechanism 5 exhibits a paper standby function that loosens and waits for the paper S while holding the front end St or the vicinity of the front end St, a plurality of print screens are displayed. Even if the long paper S is set, the paper S to be conveyed into the paper reversing unit 54 and the paper S to be conveyed out of the paper reversing unit 54 are caused to stand by in a slack state in the paper reversing unit 54. Crossing on the transport path can be avoided.

  In addition, this invention is not limited to embodiment mentioned above. For example, in the above-described embodiment, when the entire print screen on the front surface Sa of the paper S is printed, the paper S is transported to the paper reversing unit 54 by the paper transport mechanism 5 and waited at the paper reversing unit 54. In the paper S, the back surface Sb faces (contacts) the outer peripheral surface of the guide roller 541a, and the surface Sa on which the printing process is performed cannot be directly in contact with the outer peripheral surface of the guide roller 541a. When there is no need to consider problems such as ink bleeding (when fast-drying or ultra-fast-drying ink is applied, etc.), the print processing is performed on the entire print screen on the surface of the paper, and then the paper is transported. A state in which the surface of the paper faces (contacts) the outer peripheral surface of the guide roller when the mechanism transports the paper to the paper turnover portion and waits at the paper turnover portion. It can also be employed.

  Further, as shown in FIGS. 11 to 13, a pair of bobbins (first bobbin X541 and second bobbin X542) and the pair of bobbins X541 and X542 are disposed on the print unit 3 side as the paper turnover portion. A paper reversing unit X54 including a carry-in / out feeding roller unit X543 for carrying in and out the paper S with respect to the reverse path X54S formed using the bobbins bobbins X541 and X542 may be applied. The pair of bobbins (the first bobbin X541 and the second bobbin X542) can be independently rotated in forward and reverse directions. In the following description, the clockwise direction in FIG. 11 is referred to as a forward direction, and the counterclockwise direction is referred to as a reverse direction. The operation and action of the paper transport mechanism and printer using such a paper turnover portion X54 will be described. Since operations not related to the paper reversing part X54 are the same as those in the above-described embodiment, the description thereof is omitted. The first sheet S that has been fed to the paper reversing part X54 from the printing unit before the printing process is performed on one side (for example, front surface Sa) of the sheet S that has been subjected to the printing process first is rotated in the forward direction. Winding by bobbin X541. Then, by rotating the first bobbin X541 in the reverse direction, the paper S that has been waiting in the state of being wound around the first bobbin X541 is directed toward the print unit 3 toward the print unit 3 and the feed roller unit X543 (roller main body X543a). And the pinch roller X543b), and print processing is performed on the surface Sa of the paper S by the printing unit. Next, after the sheet S having the front surface Sa subjected to the printing process is taken up again by the first bobbin X541 rotated in the forward direction, the first bobbin X541 is rotated in the reverse direction and the second bobbin X542 is also in the same direction ( Rotate in the reverse direction) and rewind the sheet S around the second bobbin X542. Subsequently, the second bobbin X542 is rotated in the forward direction, and the paper S wound around the second bobbin X532 is transferred from the carry-in / out feed roller unit X543 (between the roller main body X543a and the pinch roller X543b) to the print unit side. Sequentially. Then, the sheets S with the front and back sides reversed are sequentially conveyed to the printing unit side, and the printing unit can perform the printing process on the surface that has not been subjected to the printing process (the back surface Sb in the illustrated example). 11 to 13 are schematic diagrams, in which the paper S is wound around the bobbins X541 and X542 in a state of being loosened, but the paper S is not loosened around the bobbins X541 and X542. Of course, it doesn't matter if you wind it around.

  Further, as the paper turnover portion, a paper turner having a spiral turnover path that is rotated (twisted) by 180 degrees or approximately 180 degrees while transporting the paper so that the relationship between the front surface and the back surface is reversed may be employed.

  In the above-described embodiment, the paper conveyance mechanism is applied to the sublimation thermal transfer printer. However, the paper conveyance mechanism 5 having the above-described structure and effects is applied to another thermal transfer printer such as a fusion type. It doesn't matter. Further, the paper transport mechanism according to the present invention may be applied to a printer that employs a printing method other than the thermal transfer printing method, for example, an ink jet printing method or a laser method.

  In addition, the specific configuration of each part is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

1 ... Printer (thermal transfer printer)
DESCRIPTION OF SYMBOLS 2 ... Paper feed part 3 ... Print part 4 ... Paper discharge part 5 ... Paper conveyance mechanism 51 ... Feed roller part 53 ... 1st cutter part 54, X54 ... Paper reversing part 54S ... Reverse path 55 ... Paper discharge guide part 57 ... 1st 2 Cutter part S ... Paper Sa ... Front side Sb ... Back side

Claims (5)

Paper that can be transported to a paper discharge section via a common print section that prints on the front and back surfaces of the paper that is supplied from a paper feed section that can accommodate roll-wrapped paper A transport mechanism,
A feed roller unit disposed between the paper feeding unit and the printing unit and capable of transporting paper in a feeding direction for feeding the paper toward the printing unit and a printing direction in which the printing unit can perform printing processing on the paper. When,
A first cutter unit disposed between the sheet feeding unit and the feed roller unit and cutting a sheet into a predetermined size;
It has a reverse path capable of turning over the paper that has been printed on one of the front surface and the back surface by the print unit and cut to a predetermined size by the first cutter unit, and can transport the reversed paper to the print unit Paper reversing part,
A paper transport mechanism, comprising: a paper discharge guide section that guides the paper turned upside down by the paper turnover section and printed on the other surface by the print section to the paper discharge section. 2. The paper transport mechanism according to claim 1, wherein the paper reversing unit includes a paper standby unit that suspends the paper and waits while holding the front end of the paper or the vicinity of the front end of the paper. The paper discharge guide unit feeds the paper supplied from the paper feed unit toward the feed roller unit, and the paper that has been printed on the other side by the print unit. The paper transport mechanism according to claim 1, wherein the paper transport mechanism is switchable between a paper discharge guide position that can be transported toward the paper discharge unit. A second cutter unit capable of cutting at least a boundary of each print screen with respect to a sheet on which a plurality of print screens are set is disposed between the paper discharge guide unit and the paper discharge unit. The paper transport mechanism according to any one of 1 to 3. A paper feeding unit capable of storing paper wound in a roll;
A common print unit that performs print processing on the front and back sides of the paper;
A paper discharge unit for discharging the paper that has been printed on both sides;
5. The sheet transport mechanism according to claim 1, wherein the sheet transport mechanism transports a sheet between the sheet feeding unit and the sheet discharge unit via the printing unit. Printer.

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