JP2006116812A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent wasting of a recording medium and deterioration of an image due to a fluctuation in load of a recording medium in its conveyance and to improve a throughput of a printer when a plurality of color images are recorded. <P>SOLUTION: A tip portion of paper rewound from a paper supply section 40 is cut along a straight line inclined with respect to a width direction of the paper. The paper is conveyed toward the downstream side in the conveyance direction from its tip portion by allowing it to face thermal heads 71a-73a in a printing section 70 with no printing of color images. When the paper is conveyed in the downstream side of the printing section 70 by a predetermined length, the conveyance is stopped. After that, while the paper is reversely conveyed toward the upstream side in the conveyance direction by means of a pair of conveyance rollers 34 provided to a portion at the upstream side of the printing section 70, the plurality of color images are continuously printed by means of the thermal heads 71a-73a in the printing section 70. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a printer that records a color image on a recording medium.

  Various techniques are known for printers capable of recording color images on a recording medium. For example, Patent Document 1 includes three thermal heads capable of individually recording each of yellow, magenta, and cyan colors, and the three recording heads that are drawn from the recording paper roll are conveyed in the paper feeding direction. A one-pass color thermal printer that records a color image with a thermal head is disclosed.

  Patent Document 2 discloses a 3-pass color thermal printer. In such a printer, a color thermal recording paper having a length of one frame drawn from a recording paper roll is sent out so as to face one thermal head, and then a yellow image is recorded while being pulled back, and then the recording paper. Are sent and pulled back alternately, and a magenta image is recorded at the second pull back, and a cyan image is recorded at the third pull back.

  Patent Document 3 is provided with three thermal heads of yellow, magenta, and cyan. After the recording paper drawn from the recording paper roll is conveyed in the paper feeding direction and the print preparation is completed, the recording paper is loaded. A one-pass color thermal printer that records a color image of one frame while being conveyed in the pull-back direction is disclosed. In such a printer, when a color image of one frame is recorded, the recording paper is conveyed again in the paper feeding direction and cut at the rear end portion of the color image. Then, the recording paper on which the color image is recorded is discharged, and the next one-frame color image is recorded while the recording paper that has been prepared for printing is conveyed in the pullback direction.

Here, in such a printer, when a color image is recorded while the recording paper is conveyed in the pullback direction, the image recording is finished in order from the thermal head on the upstream side in the pullback direction. For example, when the pressing force of the yellow thermal head against the recording paper rapidly decreases when the end of the recording paper passes through the recording position by the yellow thermal head, density unevenness is generated in the image by the magenta and cyan thermal heads. appear. Accordingly, in such a printer, in order to prevent the occurrence of density unevenness due to fluctuations in the transport load, the thermal heads are sequentially withdrawn so that the pressing force gradually decreases as the printing ends. In Patent Document 4, in order to solve the same problem as this, the rear end of the sheet is restrained by a pair of pressure rollers (sheet conveying roller and pinch roller) arranged on the upstream side in the conveying direction from the recording head of the printer. A technique for gradually solving is described.
Japanese Patent Application Laid-Open No. 8-174476 JP-A-9-99572 JP 2001-246769 A JP 2003-94745 A

  In the printer described in Patent Document 1, a color image can be recorded only by transporting the recording paper in one direction without transporting the recording paper back and forth. However, in such a printer, when the three thermal heads are pressed against the recording paper in order from the one where the recording paper has reached the printing position, the image is deteriorated due to load fluctuations during conveyance of the recording paper. Sometimes. Therefore, in such a printer, in order to prevent the deterioration of the image, the recording of the color image is started after all the three thermal heads are pressed against the recording paper. For this reason, the portion between the thermal head in the vicinity of the leading edge of the recording paper, that is, the length between the most upstream thermal head and the most downstream thermal head in the paper feeding direction from the leading edge of the recording paper is stretched between the thermal heads. Recording of a color image is started. For this reason, there is a problem in that an image is not formed in the length portion where the recording paper is stretched and a blank portion is formed.

  On the other hand, in the printers described in Patent Document 2 and Patent Document 3, a color image can be recorded even in the vicinity of the leading end of the recording paper, so that it is possible to prevent the recording paper from being wasted. Here, in the printer described in Patent Document 3, when the recording paper is conveyed in the pullback direction, all three thermal heads are pressed against the recording paper, so that the image is caused by load fluctuations during the conveyance of the recording paper. Is rarely worse.

  However, in the printer of Patent Document 2, it is necessary to repeat feeding and pulling of the recording paper three times in order to record a single color image. Further, in the printer of Patent Document 3, it is necessary to feed and pull back the recording paper once for each color image of one frame. Therefore, in order to record a color image of a plurality of frames in these printers, the reciprocating conveyance of the recording paper has to be repeated many times.

  Here, in the printers of Patent Document 2 and Patent Document 3, a pair of transport rollers is disposed between the recording paper roll and the thermal head, and the transport direction of the recording paper is switched by switching the driving direction of the pair of transport rollers. Is changed to either the paper feed direction or the pull back direction. Therefore, in order to record a color image of a plurality of m frames (m is an integer of 2 or more), the printer of Patent Document 2 must reciprocate the recording paper 3 m times, and the driving direction of the conveying roller pair is changed. It is necessary to switch only (6m-1) times. In the printer of Patent Document 3, the recording paper must be reciprocated and conveyed m times, and the driving direction of the conveying roller pair needs to be switched only (2m-1) times.

  As described above, when the driving direction of the conveying roller pair is switched, a time-related conveying loss occurs due to the switching. Therefore, if the number of times of switching the driving direction of the conveying roller pair is increased, the time-related conveying loss is increased accordingly, and the processing capability of the printer is lowered.

  In the printers of Patent Document 3 and Patent Document 4, it is necessary to drive a motor for moving the thermal head and the pinch roller. In that case, an image recorded on the recording paper may be deteriorated by vibration generated at the start of motor driving.

  The problem that the image deteriorates due to a sudden load fluctuation of the recording paper when the end of the recording paper passes through the contact type head and the pressure roller pair is that the recording paper is always conveyed in one direction. It is considered that this also occurs in a printer in which is recorded. In order to solve this problem, if the contact type head and the pressure roller pair are moved, as described above, the image recorded on the recording paper is deteriorated by the vibration generated at the start of driving the motor. It will be.

  Accordingly, a main object of the present invention is to improve processing performance when recording a plurality of color images while suppressing image deterioration caused by waste of the recording medium and load fluctuations during conveyance of the recording medium. To provide a printer.

Means for Solving the Problems and Effects of the Invention

  The printer of the present invention includes a supply unit storing a recording medium, an image recording unit having a plurality of image recording heads capable of recording a color image in contact with the recording medium, and the recording medium facing the plurality of image recording heads. A transport mechanism capable of transporting in a first direction from the supply unit toward the image recording unit and a second direction opposite to the first direction, the supply unit, and the image recording unit. And a cutting mechanism capable of cutting the recording medium conveyed by the conveying mechanism, and the leading end of the recording medium reaches the image recording unit by conveying the recording medium in the first direction. Before cutting, the cutting control means for controlling the cutting mechanism so that the leading end of the recording medium is cut along a straight line inclined with respect to the width direction of the recording medium, and the leading end of the recording medium is separated from the image recording unit. Said first direction A transport control means for controlling the transport mechanism so that the recording medium is transported in the second direction after being transported in the first direction until reaching a distant position, and the second control mechanism by the transport mechanism. The image recording control unit is configured to control the image recording unit so that a color image is recorded by the image recording unit on a recording medium transported in a direction.

  Note that “the leading end of the recording medium reaches a position away from the image recording unit in the first direction” means that “the recording medium is conveyed in the first direction from the supply unit to the image recording unit and recorded. This means that the leading end of the medium reaches a position downstream of the image recording unit.

  According to this configuration, a plurality of color images can be recorded on the recording medium conveyed in the second direction after the recording medium is conveyed in the first direction from the supply unit toward the image recording unit. Therefore, a color image can be recorded in the vicinity of the leading end of the recording medium (the region from the leading end of the recording medium portion that is transported in the first direction and then reversely fed in the second direction), and the recording medium is transported. It is possible to suppress the deterioration of the image due to the load fluctuation inside. Further, even when a plurality of color images are recorded on the recording medium, it is only necessary to reciprocate the recording medium once, and it is only necessary to switch the conveying direction of the recording medium in the conveying mechanism once. Transport loss can be reduced. As a result, when a plurality of color images are recorded on the recording medium, it is possible to improve the processing capability of the printer while suppressing image deterioration caused by waste of the recording medium and load fluctuation during conveyance of the recording medium.

  Further, since the leading end of the recording medium is cut along a straight line inclined with respect to the width direction of the recording medium, the leading end of the recording medium conveyed in the second direction passes through the image recording position by the image recording head. At this time, the pressing force of the image recording head against the recording medium does not decrease rapidly but gradually decreases. Therefore, even when an image is recorded by another image recording head when the leading end of the recording medium passes through the image recording position by the image recording head, an image caused by load fluctuation during conveyance of the recording medium is performed. Deterioration can be suppressed.

  In the printer according to the aspect of the invention, the transport mechanism may be capable of transporting the recording medium in the second direction by applying a transport force to the recording medium between the supply unit and the image recording unit. .

  According to this configuration, when a plurality of color images are recorded on the recording medium conveyed in the second direction, it is possible to effectively suppress deterioration of the image due to load fluctuations during conveyance of the recording medium. be able to.

  The printer of the present invention includes a supply unit storing a recording medium, an image recording unit having an image recording head capable of recording an image, and a recording medium facing the image recording head from the supply unit to the image recording unit. A transport mechanism that is transportable in a first direction toward the second direction and a second direction that is opposite to the first direction, and is disposed between the supply unit and the image recording unit, and the transport mechanism A cutting mechanism capable of cutting the recording medium conveyed by the recording medium, a pressure roller pair disposed downstream of the image recording unit and capable of sandwiching the recording medium, and the recording medium being conveyed in the first direction. The cutting mechanism controls the cutting mechanism so that the leading edge of the recording medium is cut along a straight line inclined with respect to the width direction of the recording medium before the leading edge of the recording medium reaches the image recording unit. Control means and recording medium The transport mechanism is controlled so that the recording medium is transported in the second direction after being transported in the first direction until the leading edge of the recording medium reaches a position away from the image recording unit in the first direction. And an image recording control unit that controls the image recording unit so that an image is recorded by the image recording unit on a recording medium that is conveyed in the second direction by the conveyance mechanism. It is characterized by having.

  The “downstream side” relates to a first direction from the supply unit toward the image recording unit.

  According to this configuration, a plurality of color images can be recorded on the recording medium conveyed in the second direction after the recording medium is conveyed in the first direction from the supply unit toward the image recording unit. Therefore, a color image can be recorded in the vicinity of the leading end of the recording medium (the region from the leading end of the recording medium portion that is transported in the first direction and then reversely fed in the second direction), and the recording medium is transported. It is possible to suppress the deterioration of the image due to the load fluctuation inside. Further, even when a plurality of color images are recorded on the recording medium, it is only necessary to reciprocate the recording medium once, and it is only necessary to switch the conveying direction of the recording medium in the conveying mechanism once. Transport loss can be reduced. As a result, when a plurality of color images are recorded on the recording medium, it is possible to improve the processing capability of the printer while suppressing image deterioration caused by waste of the recording medium and load fluctuation during conveyance of the recording medium.

  Further, since the leading end of the recording medium is cut along a straight line inclined with respect to the width direction of the recording medium, the leading end of the recording medium conveyed in the second direction passes through the pressure roller pair (pressure roller pair). The pressure between the pressure roller pair against the recording medium does not decrease rapidly but gradually decreases. Therefore, even when the image recording head performs image recording when the leading end of the recording medium passes through the pressure roller pair, image deterioration due to load fluctuations during conveyance of the recording medium can be suppressed. it can.

  In the printer according to the aspect of the invention, the transport mechanism may be capable of transporting the recording medium in the second direction by applying a transport force to the recording medium between the supply unit and the image recording unit. .

  According to this configuration, when a plurality of color images are recorded on the recording medium conveyed in the second direction, it is possible to effectively suppress deterioration of the image due to load fluctuations during conveyance of the recording medium. be able to.

  In the printer of the present invention, the image recording unit may include an image recording head capable of recording an image while being in contact with a recording medium.

  According to this configuration, since the leading end of the recording medium is cut along a straight line inclined with respect to the width direction of the recording medium, the leading end of the recording medium conveyed in the second direction is an image recording position by the image recording head. When passing, the pressing force of the image recording head against the recording medium does not decrease rapidly but gradually decreases. Therefore, even when an image is recorded by another image recording head when the leading end of the recording medium passes through the image recording position by the image recording head, an image caused by load fluctuation during conveyance of the recording medium is performed. Deterioration can be suppressed.

  In the printer of the present invention, the image recording unit may have a plurality of image recording heads and be capable of recording a color image.

  According to this configuration, it is possible to record a color image while suppressing image deterioration due to load fluctuation during conveyance of the recording medium.

  In the printer of the present invention, the cutting mechanism includes a first cutting unit capable of cutting along a straight line in which a leading end of the recording medium is inclined with respect to the width direction of the recording medium, and cutting the recording medium along the width direction. And a possible second cutting section.

  According to this configuration, a cutting part that cuts the leading end of the recording medium along a straight line inclined with respect to the width direction of the recording medium and a cutting part that cuts the recording medium along the width direction are separately provided. Control such as changing the inclination of the cutting blade becomes unnecessary.

  In the printer according to the aspect of the invention, the cutting mechanism may include a cutting unit capable of cutting the recording medium along a straight line inclined with respect to the width direction of the recording medium and cutting the recording medium along the width direction. You may have.

  According to this configuration, a cutting part that cuts the leading end of the recording medium along a straight line inclined with respect to the width direction of the recording medium and a cutting part that cuts the recording medium along the width direction are provided in common. The number of parts can be reduced and the manufacturing cost can be reduced.

  In the printer according to the aspect of the invention, the cutting unit includes a cutting blade that can rotate with a predetermined position outside the conveyance path of the recording medium as a fulcrum, and a rotation drive mechanism that rotates the cutting blade with the predetermined position as a fulcrum. May be.

  According to this configuration, the angle between the cutting blade and the width direction of the recording medium can be easily adjusted.

  The printer of the present invention includes a supply unit storing a recording medium, an image recording unit having a plurality of image recording heads capable of recording a color image in contact with the recording medium, and the recording medium facing the plurality of image recording heads. And a conveyance mechanism that can be conveyed in the direction from the supply unit toward the image recording unit, and the recording medium that is arranged between the supply unit and the image recording unit and that is conveyed by the conveyance mechanism. First possible cutting mechanism and straight line in which the rear end of the recording medium is inclined with respect to the width direction of the recording medium before the rear end of the recording medium reaches the image recording unit by being conveyed A cutting control unit that controls the first cutting mechanism, a conveyance control unit that controls the conveyance mechanism, and a recording medium that is conveyed by the conveyance mechanism. By As a color image is recorded, it is characterized by comprising an image recording control means for controlling said image recording unit.

  According to this configuration, since the rear end of the recording medium is cut along a straight line inclined with respect to the width direction of the recording medium, the rear end of the recording medium conveyed in the direction from the supply unit to the image recording unit is When passing the image recording position by the image recording head, the pressing force of the image recording head against the recording medium does not decrease rapidly but gradually decreases. Therefore, even when an image is recorded by another image recording head when the rear end portion of the recording medium passes the image recording position by the image recording head, the recording medium is caused by load fluctuations during conveyance of the recording medium. Image deterioration can be suppressed.

  The printer of the present invention may further include a second cutting mechanism that is disposed on the downstream side of the image recording unit and that can cut the recording medium conveyed by the conveyance mechanism.

  According to this configuration, the rear end region of the recording medium can be cut.

  The printer of the present invention includes a supply unit storing a recording medium, an image recording unit having an image recording head capable of recording an image, and a recording medium facing the image recording head from the supply unit to the image recording unit. A transport mechanism capable of transporting in a direction toward the head, a first cutting mechanism disposed between the supply unit and the image recording unit and capable of cutting a recording medium transported by the transport mechanism, and the first A pair of pressure rollers disposed between the cutting mechanism and the image recording unit, and a rear end of the recording medium before the rear end of the recording medium reaches the pressure roller pair by conveying the recording medium. Is cut along a straight line inclined with respect to the width direction of the recording medium, the cutting control means for controlling the first cutting mechanism, the transport control means for controlling the transport mechanism, and the transport mechanism. Being transported As an image is recorded by the image recording unit on the recording medium, it is characterized by comprising an image recording control means for controlling said image recording unit.

  According to this configuration, since the rear end of the recording medium is cut along a straight line inclined with respect to the width direction of the recording medium, the rear end of the recording medium conveyed in the direction from the supply unit to the image recording unit is When passing through the pressure roller pair (from the state of being pinched by the pressure roller pair to the state of not being pinched), the pressing force of the pressure roller pair against the recording medium is gradually reduced rather than suddenly reduced. Therefore, even when the image recording head is recording an image when the rear end of the recording medium passes through the pressure roller pair, image deterioration due to load fluctuations during conveyance of the recording medium is suppressed. Can do.

  The printer of the present invention may further include a second cutting mechanism that is disposed on the downstream side of the image recording unit and that can cut the recording medium conveyed by the conveyance mechanism.

  According to this configuration, the rear end region of the recording medium can be cut.

  In the printer of the present invention, the image recording unit may include an image recording head capable of recording an image while being in contact with a recording medium.

  According to this configuration, since the rear end of the recording medium is cut along a straight line inclined with respect to the width direction of the recording medium, the rear end of the recording medium conveyed in the direction from the supply unit to the image recording unit is When passing the image recording position by the image recording head, the pressing force of the image recording head against the recording medium does not decrease rapidly but gradually decreases. Therefore, even when an image is recorded by another image recording head when the rear end portion of the recording medium passes the image recording position by the image recording head, the recording medium is caused by load fluctuations during conveyance of the recording medium. Image deterioration can be suppressed.

  In the printer of the present invention, the image recording unit may have a plurality of image recording heads and be capable of recording a color image.

  According to this configuration, it is possible to record a color image while suppressing image deterioration due to load fluctuation during conveyance of the recording medium.

  In the printer according to the aspect of the invention, the first cutting mechanism may include a first cutting unit capable of cutting along a straight line whose rear end of the recording medium is inclined with respect to the width direction of the recording medium, and the width direction of the recording medium. And a second cutting part that can be cut along the line.

  According to this configuration, the cutting portion for cutting the rear end of the recording medium along a straight line inclined with respect to the width direction of the recording medium and the cutting portion for cutting the recording medium along the width direction are separately provided. Control such as changing the inclination of the cutting blade becomes unnecessary.

  In the printer of the present invention, the first cutting mechanism can cut the recording medium along a straight line whose rear end is inclined with respect to the width direction of the recording medium and can cut the recording medium along the width direction. An appropriate cutting part may be provided.

  According to this configuration, the cutting portion that cuts the rear end of the recording medium along a straight line inclined with respect to the width direction of the recording medium and the cutting portion that cuts the recording medium along the width direction are provided in common. The number of parts can be reduced and the manufacturing cost can be reduced.

  In the printer according to the aspect of the invention, the cutting unit includes a cutting blade that can rotate with a predetermined position outside the conveyance path of the recording medium as a fulcrum, and a rotation drive mechanism that rotates the cutting blade with the predetermined position as a fulcrum. May be.

  According to this configuration, the angle between the cutting blade and the width direction of the recording medium can be easily adjusted.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an external perspective view of a printer according to a first embodiment of the present invention. FIG. 2 is a diagram illustrating a schematic configuration of a printing unit of the printer of FIG. FIG. 3 is a diagram illustrating the movement of the conveying roller pair and the feeding roller pair of the printer of FIG. FIG. 4 is a diagram showing a schematic configuration of the cutting unit of the printer of FIG. FIG. 5 is a block diagram of a main part of the printer of FIG. 1 and a control device to which these are connected.

  A thermal sublimation thermal printer 1 shown in FIG. 1 (hereinafter referred to as “printer 1”) includes an operation unit 10, a control device 20, and a printing unit 30. The operation unit 10 is for an operator to operate the printer 1 and has a display 11 for displaying various information about the printer 1 and notifying the operator. Here, in the present embodiment, a touch panel method is adopted for the operation unit 10, and an operation screen 12 including various buttons is displayed on the display 10. Accordingly, the operator can execute an operation on the printer 1 by touching the operation screen 12.

  The control device 20 receives input from the operation unit 10 and controls various operations in the printer 1. In addition, the control device 20 has a plurality of data input units 20a for acquiring print data from various storage media such as a card slot and a disk drive. The storage medium may be any medium that can store print data, such as a CD-ROM or a memory card.

  Here, the operation unit 10 and the control device 20 are fixedly arranged on the upper surface of the housing 30 a that houses the print unit 30. Here, the display surface of the display 11 of the operation unit 10 and the storage medium insertion surface of the data input unit 20a of the control device 20 substantially coincide with the front of the printer 1 (housing 30a) (the surface on the left front side in FIG. 1). ing. Therefore, it is easy for the operator heading to the front of the printer 1 to operate the display 11 and the data input unit 21.

  The housing 30a has a substantially rectangular parallelepiped shape, and the lateral width (front width) D1 is smaller than the depth D2. Therefore, the printer 1 can be installed even in a relatively narrow space. Furthermore, an opening 95 is formed on the front surface of the housing 30a for drawing out a print box 96 (described later) housed in the housing 30a to the outside of the housing 30a.

  As shown in FIG. 2, the print unit 30 includes a paper supply unit 40 that holds a paper wound in a roll shape and a paper winding unit that winds up the paper that has been unwound from the paper supply unit 40. Between the take-up unit 80 and the paper supply unit 40 and the paper take-up unit 80, there is a transport mechanism 38 that can transport the paper along a transport path curved in one direction. A cutting unit 50, an overcoat unit 60, and a printing unit 70 are disposed between the paper supply unit 40 and the paper winding unit 80 from the upstream side to the downstream side of the transport path. A print box 96 is provided near the conveyance path between the paper supply unit 40 and the cutting unit 50.

  In the present embodiment, “paper transport direction (transport direction)” means a direction from the paper supply unit 40 toward the paper winding unit 80. Further, the “paper front end” and the “image front end” mean the end on the downstream side of the paper or the image transport direction, and the “paper rear end” and “image rear end” The term “edge” means an end portion on the upstream side of the sheet or image in the conveying direction.

  The paper supply unit 40 has a magazine case 41 provided in the uppermost stream of the transport path, and a long paper is wound around the rotation shaft 43 so that the printing surface is on the outside. The wound winding part 45 is loaded. Here, the rotating shaft 43 is driven to rotate counterclockwise in FIG. 2 when the sheet is unwound from the sheet supply unit 40 and conveyed toward the downstream side in the conveying direction by the motor 43a (see FIG. 5). When the unwound paper is taken up by the paper supply unit 40, it is rotated clockwise in FIG. The rotary shaft 43 is connected to a shaft (not shown) that is rotationally driven by a motor 43a via a one-way clutch 43c having the same function as one-way clutches 34c and 35c described later.

  The transport mechanism 38 is arranged in order from the upstream side in the transport direction, and includes a pair of paper feed rollers 31 that can transport the paper unrolled from the winding unit 45 of the paper supply unit 40 upward, and the cutting unit 50. Also, a turn roller pair 32 that is arranged on the upstream side in the transport direction and changes the transport direction of the paper transported upward, and a pressure roller pair that can sandwich the paper between the cutting unit 50 and the overcoat unit 60. 33 and a pair of transport rollers 34 capable of transporting the paper, and a paper which is disposed downstream of the printing unit 70 in the transport direction and transported downstream of the printing unit 70 in the transport direction. A feed roller pair 35 for feeding the inside is provided. In this embodiment, the paper feed roller pair 31, the turn roller pair 32, the pressure roller pair 33, and the feed roller pair 35 are made of resin rollers, and the transport roller pair 34 is made of a metal roller. Has been.

  Here, the pair of feed rollers 31, the pair of turn rollers 32, the pair of pressure rollers 33, the pair of transport rollers 34 and the pair of feed rollers 35 are arranged on a circumference having a predetermined radius (indicated by a two-dot chain line in FIG. 2). It is arranged along. As can be seen from FIG. 2, the head portions 61 and 71 to 73 of the overcoat portion 60 and the printing portion 70 are also arranged along the circumference, and the paper supply portion 40 and the paper take-up portion 80 are It arrange | positions inside the said periphery.

  The paper feed roller pair 31, the transport roller pair 34, and the feed roller pair 35 are connected to motors 31a, 34a, and 35a (see FIG. 5) controlled by the transport control unit 27a (see FIG. 5), respectively, and are rotationally driven. Is possible.

  Here, the movement of the transport roller pair 34 and the feed roller pair 35 will be described in detail with reference to FIG. FIG. 3A shows the movement of the transport roller pair 34 and the feed roller pair 35 when the paper is transported downstream in the transport direction, and FIG. 3B shows that the paper is upstream in the transport direction. The movement of the conveying roller pair 34 and the feeding roller pair 35 during reverse feeding is shown. As shown in FIG. 3, the conveyance roller pair 34 includes a driving roller 34d and a driven roller 34e. The drive roller 34d is connected to a shaft 34b that is rotationally driven by a motor 34a via a one-way clutch 34c. Similarly, the feed roller pair 35 includes a drive roller 35d and a driven roller 35e, and the drive roller 35d is connected to a shaft 35b that is rotationally driven by a motor 35a via a one-way clutch 35c.

  Since the one-way clutches 34c and 35c have the same function, the function of the one-way clutch 34c will be described here. The one-way clutch 34c is fixed to the driving roller 34d and rotates together with the driving roller 34d. When the drive roller 34d rotates faster than the rotational speed of the shaft 34b, the rotational force of the shaft 34b is not transmitted to the drive roller 34d, and the drive roller 35d rotates idly with respect to the shaft 34b. In other cases, the rotational force of the shaft 34b is transmitted to the drive roller 34d via the one-way clutch 34c, and the shaft 34b and the drive roller 34d rotate together.

  Therefore, when the conveyance roller pair 34 holds the sheet, the conveyance speed of the sheet is slower than the conveyance speed of the sheet based on the rotational force of the conveyance roller pair 34 driven by the motor 34a. Is transmitted to the conveying roller pair 34. Then, the sheet is transported with a transport force applied by the transport roller pair 34. On the other hand, when the paper conveyance speed is faster than the paper conveyance speed based on the rotational force of the conveyance roller pair 34 driven by the motor 34a, the driving force of the motor 34a is not transmitted to the conveyance roller pair 34 and is conveyed. The roller pair 34 is idle. That is, the transport roller pair 34 is driven to rotate at a rotational speed corresponding to the paper transport speed.

  Here, the sheet conveying speed based on the rotational force of the conveying roller pair 34 driven by the motor 34a is V1, and the sheet conveying speed based on the rotational force of the feeding roller pair 34 driven by the motor 35a is V2. Consider the case of transporting a sheet downstream in the transport direction with reference to (a). At this time, as will be described later, after the leading edge of the paper reaches the feed roller pair 35 and is nipped, the drive of the transport roller pair 34 is stopped, and the transport speed V1 becomes zero. On the other hand, the feed roller pair 35 is rotationally driven by the driving force of the motor 35a being transmitted through the shaft 35b and the one-way clutch 35c. Since the sheet sandwiched between the transport roller pair 34 is transported at the transport speed V2, the transport roller pair 34 is idled by the function of the one-way clutch 34c.

  Next, with reference to FIG. 3B, consider a case where the paper is fed back upstream in the transport direction. At this time, as will be described later, since the driving of the feed roller pair 35 is stopped, the conveyance speed V2 becomes zero. On the other hand, the conveying roller pair 34 is rotationally driven by the driving force of the motor 34a being transmitted through the shaft 34b and the one-way clutch 34c. Since the sheet sandwiched between the feed roller pair 35 is reversely fed at the conveyance speed V1, the feed roller pair 35 rotates idly by the function of the one-way clutch 35c.

  The pair of paper feed rollers 31 is also connected to a shaft (not shown) that is rotationally driven by a motor 31a via a one-way clutch 31c having the same function as the one-way clutches 34c and 35c described above. Accordingly, the paper feed roller pair 31, the transport roller pair 34, and the feed roller pair 35 are configured to remove the paper unrolled from the paper supply unit 40 by individually controlling the motors 31a, 34a, and 35a by the transport control unit 27a. The sheet can be conveyed downstream in the conveying direction and taken up by the paper take-up unit 80, and the paper once taken up in the paper take-up unit 80 can be unwound and unwound from the paper take-up unit 80. The printed paper can be fed back toward the upstream side in the transport direction.

  Further, the printing unit 30 includes an encoder 36 that can detect the number of rotations of the conveyance roller pair 34. Here, as described above, the transport roller pair 34 is driven and rotated by the motor 34a to transport the paper, and is driven and rotated along with the paper transported by the feed roller pair 35. obtain. The encoder 36 can detect the number of rotations of the conveyance roller pair 34 even when the conveyance roller 34 is in any of the above states.

  The cutting part 50 is disposed between the turn roller pair 32 and the pressure roller pair 33. The cutting unit 50 includes a movable blade 51 disposed above the transport path, a fixed blade 52 disposed below the transport path, a rotation drive mechanism 58 (see FIG. 4), and a chip box 59. Have. Here, the movable blade 51 and the fixed blade 52 can be rotated by a rotation driving mechanism 58 with a fulcrum 50a provided at a position corresponding to the center in the width direction of the paper transport path as a fulcrum.

  As shown in FIG. 4A, the movable blade 51 is a rectangular blade that is longer than the entire width of the sheet conveyance path (shown by a one-dot chain line in FIG. 4A). The movable blade 51 is connected to a drive mechanism 53 (see FIG. 5) controlled by the cutting control unit 27c, and can move up and down while being maintained substantially parallel to the paper conveyance path.

  The rotation drive mechanism 58 includes a rotation member 54, a cam 55, and a drive mechanism 57. The rotating member 54 is a disk-shaped member and is rotatably attached to one end portion of the movable blade 51. The angle between the movable blade 51 and the rotating member 54 can be changed. The outer peripheral surface of the cam 55 is in contact with the outer peripheral surface of the rotating member 54. Here, as shown in FIG. 4B, which is a cross-sectional view taken along line LL in FIG. 4A, the cam 55 is a substantially elliptical member, and the rotation shaft 56 is located at an eccentric position. Has been placed. The rotating shaft 56 of the cam 55 is connected to a drive mechanism 57 controlled by the cutting control unit 27c. Therefore, the drive mechanism 57 drives the rotary shaft 56 to move the rotary member 54 left and right in FIG. 4A via the cam 55. Then, since the one end part of the movable blade 51 also moves with the movement of the rotating member 54, the movable blade 51 rotates with the fulcrum 50a as a fulcrum. In FIG. 4A, the state when the movable blade 51 rotates is shown by a broken line. In addition, one end of the movable blade 51 is returned to a position where the movable blade 51 rotated to a position inclined with respect to the paper width direction by the rotation drive mechanism 58 by the spring 51a returns to a position coinciding with the paper width direction (FIG. 4). In the left direction). On the other hand, the fixed blade 52 is a rectangular blade that is longer than the entire width of the sheet conveyance path, and moves in the same manner as the movable blade 51.

  Accordingly, when the cutting control unit 27c controls the drive mechanism 53 to move the moving blade 51 downward in a state where the sheet is disposed at the cutting position by the cutting unit 50, the moving blade 51 and the fixed blade 52 are moved downward. The paper is cut by the interaction. Here, before the movable blade 51 is moved downward, the paper can be cut along the width direction by adjusting the angle of the movable blade 51 with respect to the width direction of the paper by controlling the drive mechanism 57. The paper can also be cut diagonally. In the printer 1 of the present embodiment, as will be described later, the cutting unit 50 cuts the paper at the leading edge of the paper, the leading edge and the trailing edge of each image.

  The chip box 59 is disposed below the movable blade 51 and the fixed blade 52. Therefore, when the paper is cut at the leading edge of the paper, the leading edge or the trailing edge of each image, the cut chips (margins) are stored in the chip box 59.

  The overcoat unit 60 is disposed on the downstream side of the conveyance roller pair 34 in the conveyance direction. The overcoat part 60 has one head part 61. The head unit 61 is for performing a colorless and transparent overcoat (OC) on the surface of the paper on which an image is printed. Thus, by overcoating the surface of the paper, the light resistance of the image printed on the paper can be improved and the surface of the paper can be protected. Further, by selecting the material of the overcoat, the gloss of the print can be improved and a high-quality print can be provided.

  The printing unit 70 is disposed between the overcoat unit 60 and the feed roller pair 35. The printing unit 70 has three head units 71 to 73. The head portions 71 to 73 are for performing printing corresponding to cyan (C), magenta (M), and yellow (Y), respectively. Here, in the printer 1, a head unit 71 corresponding to cyan, a head unit 72 corresponding to magenta, and a head unit 73 corresponding to yellow are provided in this order from the upstream side in the transport direction to the downstream side in the transport direction. In the printer 1, the transport roller pair 34 is disposed on the upstream side in the transport direction of the overcoat unit 60 and the printing unit 70, and the feed roller pair 35 is disposed on the downstream side in the transport direction.

  In the printer 1 of the present embodiment, when the paper unrolled from the paper supply unit 40 is conveyed toward the downstream side in the conveyance direction, the overcoat in the overcoat unit 60 and the color image in the printing unit 70 are performed. Is not performed, and when the paper once wound on the paper take-up unit 80 disposed on the downstream side in the transport direction from the print unit 70 is fed back toward the upstream side in the transport direction, the print unit 70 The printing of the image at and the overcoat at the overcoat unit 60 are performed. Accordingly, the printer 1 can print a color image in the order of yellow, magenta, and cyan on the paper surface, and can further overcoat the paper surface on which the color image is printed.

  Next, a schematic configuration of the head units 61 and 71 to 73 will be described. In addition, since the structure of the head parts 61 and 71 to 73 is the same, only the head part 73 will be described in detail here.

  The head unit 73 includes a thermal head 73a having a large number of heating elements (not shown) arranged over the entire width of the paper conveyance path, and a tip portion of the thermal head 73a (in the vicinity of the paper conveyance path and the heating elements are arranged). A platen roller 73b facing the other end, a tape-like ribbon 73c having an ink area to which ink corresponding to yellow is attached, a ribbon supply roller 73d around which a ribbon 73c before printing is wound, and a post-printing ribbon A ribbon take-up roller 73e for taking up the ribbon 73c.

  Here, the thermal head 73a can be moved back and forth with respect to the paper transport path by an elevating mechanism 73f (see FIG. 5). Therefore, the thermal head 73a can selectively take the print position where the ribbon 73c and the paper are pressed against each other and the retracted position where the paper 73 is not pressed between the vicinity of the tip and the platen roller 73b.

  In the head unit 73, when the paper is conveyed between the thermal head 73a and the platen roller 73b in a state where the thermal head 73a is disposed at the printing position, the ink of the ribbon 73c heated by the thermal head 73a. Thus, a color image corresponding to yellow can be printed on the paper. At this time, when the sheet is conveyed between the thermal head 73a and the platen roller 73b, the ribbon 73c is also moved from the ribbon supply roller 73d toward the ribbon take-up roller 73e as the sheet is conveyed. Sent.

  The head unit 61 and the head units 71 and 72 are similar to the head unit 73 in that the thermal heads 61a, 71a and 72a, the platen rollers 61b, 71b and 72b, the ribbons 61c, 71c and 72c, and the ribbon supply roller 61d. 71d, 72d, ribbon take-up rollers 61e, 71e, 72e, and elevating mechanisms 61f, 71f, 72f, respectively.

  Here, in the head unit 61 and the head units 71 and 72, ink corresponding to colorless and transparent, cyan and magenta, respectively, instead of the tape-like ribbon 73c having an ink region to which ink corresponding to yellow of the head unit 73 is attached. Tape-shaped ribbons 61c, 71c, and 72c having an ink region to which are attached are used.

  A pair of guides 75 a to 75 c are disposed between the head portion 61 of the overcoat portion 60 and the head portions 71 to 73 of the printing portion 70, respectively. Each of the pair of guides 75a to 75c includes two plate-like members, and guides the sheet (mainly the leading end portion of the sheet) conveyed between the head units 61 and 71 to 73, respectively. is there. Accordingly, the pair of guides 75a to 75c are arranged so as to face each other with a predetermined interval across the sheet conveyance path.

  The paper take-up unit 80 has a storage case 81 provided on the most downstream side of the transport path. The storage case 81 has a substantially cylindrical shape, and a part of the storage case 81 opens as a paper insertion opening 82. In the present embodiment, as shown in FIG. 2, the central angle of the portion that becomes the insertion port 82 is about 90 degrees, and one edge 82a is in the vicinity of the left end of the storage case 81, and the other The edge portion 82 b is in the vicinity of the upper end portion of the storage case 81.

  Here, the feeding roller pair 35 is disposed in the vicinity of the upper portion of the edge portion 82 a of the storage case 81, and the sheet conveyed downward by the feeding roller pair 35 is located in the storage case 81 from the vicinity of the end portion 82 a of the insertion port 82. Inserted into. The paper inserted into the paper winding unit 80 is guided by contacting the inner peripheral surface of the storage case 81. As a result, in the storage case 81, the paper is wound in order from the leading edge of the paper so that the printing surface becomes the outer surface according to the curl of the paper. The storage case 81 is rotatably provided with four winding rollers 83a to 83d. A part of each of the winding rollers 83 a to 83 d protrudes inward from the inner peripheral surface of the storage case 81. Accordingly, since the frictional force when the paper comes into contact with the inner peripheral surface of the storage case 81 is reduced, the paper is prevented from being damaged.

  The print box 96 is for discharging the paper (print) on which each color image printed by the cutting unit 50 is printed after the image is printed in the printing unit 70 and the overcoat unit 60 is overcoated. Is. The print box 96 is a box-shaped member having an upper end opened, and is supported by a support shaft 97 at the lower end to be rotatable. Accordingly, the print box 96 has a state in which the print box 96 is housed in the housing 30a (shown by a solid line in FIG. 2) and an upper end portion of the print box 96 through the opening 95 provided on the front surface (right surface in FIG. 2). A state in which the vicinity is pulled out of the housing 30a (a state indicated by a broken line in FIG. 2) can be taken. Therefore, the operator can easily take out the paper on which each color image is printed by pulling out the upper end portion of the print box 96 from the front of the printer 1 (housing 30a).

  A sorting mechanism (not shown) is provided above the print box 96 so as to be close to the transport path upstream of the turn roller pair 32 in the transport direction. In this sorting mechanism, the paper is fed back toward the upstream side in the conveyance direction when the paper is wound around the paper supply unit 40 and when the paper on which each color image is printed is discharged to the print box 96. It is possible to switch the paper transport path when printing. Therefore, by controlling the sorting mechanism, only the paper on which each color image is printed can be stored in the print box 96.

  Further, an image detection sensor 90 that can detect an end portion (mainly a rear end portion of the image) of an image printed on a sheet conveyed along the conveyance path, on the upstream side of the cutting unit 50 in the conveyance direction. Is provided. On the other hand, a paper detection sensor 91 that can detect the edge of the paper is provided upstream of the overcoat unit 60 in the transport direction. In the present embodiment, the end of the overcoat unit 60 on the upstream side in the conveyance direction and the detection position by the paper detection sensor 91 substantially coincide with each other.

  As shown in FIG. 5, the control device 20 includes a motor 43 a that drives the rotation shaft 43 of the paper supply unit 40, a motor 31 a that drives the paper feed roller pair 31, the transport roller pair 34, and the feed roller pair 35, respectively. 34a, 35a, an encoder 36 for detecting the rotation speed of the conveying roller pair 34, driving mechanisms 53, 57 for the moving blade 51 of the cutting unit 50, and thermal heads 61a, 71a-73a of the overcoat unit 60 and the printing unit 70. The elevator mechanisms 61f and 71f to 73f and the drivers 61g and 71g to 73g, the image detection sensor 90, the paper detection sensor 91, and the operation unit 10 are respectively connected.

  The control device 20 includes hardware such as a CPU, a ROM, and a RAM controlled by appropriate software, and includes a maximum winding amount storage unit 21, a print information storage unit 22, and a necessary winding amount calculation unit. 23, a comparison unit 24, a winding amount determination unit 25, a conveyance amount detection unit 26, a conveyance control unit 27a, a print control unit 27b, and a cutting control unit 27c.

  The maximum winding amount storage unit 21 maximizes the maximum length of paper that can be transported downstream in the transport direction from the printing unit 70 when the paper is transported from the paper supply unit 40 toward the paper winding unit 80. It is memorized as a winding amount. The maximum winding amount is determined by the length of the conveyance path between the printing position by the head unit 73 arranged on the most downstream side in the conveyance direction of the printing unit 70 and the insertion port 82 of the sheet winding unit 80, and the sheet winding. This value is calculated by adding together the length of paper that can be taken up in the storage case 81 of the unit 80. The maximum winding amount is input to the maximum winding amount storage unit 21 by the operator.

  Here, the maximum winding amount largely varies depending on the size of the storage case 81. The length of paper that can be wound in the storage case 81 may be the maximum length of paper that can actually be stored in the storage case 81, or the maximum length of paper that can be stored in the storage case 81. It may be shorter than the length and can be set arbitrarily. Therefore, in the present embodiment, the length of the paper that can be wound in the storage case 81 used when the maximum winding amount is calculated is that the paper is not damaged or scratched in the storage case 81. The length of the range is set to be shorter than the maximum length of paper that can be stored in the storage case 81.

  The print information storage unit 22 stores various setting values when a color image is printed. Here, the set values include the print length of one frame for each print type (the length in the transport direction), the number of prints (the number of frames), the length of the margin formed between adjacent images, and the head heat dissipation. Includes additional length. As the print length of one frame for each print type, a plurality of values are stored for each of a plurality of print types such as a standard size and a panorama size, for example. As the number of prints, a value input for each order by the operator before printing is stored. Further, the length of the margin between the images and the additional length for heat radiation of the head are stored as values input by the operator before starting printing. The additional length is such that the temperatures of the thermal heads 71a, 72a, 73a that have generated heat for printing an image and the thermal head 61a that has generated heat for overcoating are substantially the same as the ambient temperature after energization. The sheet is set to such a length that the sheet faces each of the thermal heads 61a and 71a to 73a. In the present embodiment, the time required for each of the thermal heads 61a, 71a to 73a that have generated heat to be substantially the same as the ambient temperature, and the sheet to be fed back toward the upstream side in the transport direction. The additional length is calculated by the product with the conveyance speed.

  The necessary winding amount calculation unit 23 calculates the length of paper necessary for printing all of a plurality of color images included in one order as the necessary winding amount. In other words, in order to print all of a plurality of color images included in one order, before the printing of the color image by the printing unit 70, paper having a length capable of printing these color images is printed on the printing unit. It is necessary to carry the sheet downstream in the carrying direction from 70. Therefore, when the paper is conveyed from the paper supply unit 40 toward the paper take-up unit 80, the printing position by the head unit 73 of the printing unit 70 is used to print all of the plurality of color images included in one order. The length of the paper to be transported exceeding this is calculated as the required winding amount.

  Here, the necessary winding amount will be described with reference to FIG. FIG. 6 is a diagram illustrating a state in which a plurality of color images included in one order are printed in the vicinity of the leading end of the paper. FIG. 6 shows a case where six images of the same print type are included in one order. As shown in FIG. 6, an area corresponding to the additional length z for heat radiation of the head is provided in the vicinity of the front end (left end portion in FIG. 6) of the sheet, and from there toward the upstream side (right side in FIG. 6) The area corresponding to the print length x and the area corresponding to the margin length y are alternately provided by the number n of prints.

Accordingly, in the necessary winding amount calculation unit 23, when the print type and the number of prints of a color image included in one order are input by the operator before the start of printing, each value stored in the print information storage unit 22 is set. Based on this, the required winding amount L corresponding to one order is calculated by the following equation.
L = z + x * n + y * (n-1)

  The comparison unit 24 compares the required winding amount calculated by the required winding amount calculation unit 23 with the maximum winding amount stored in the maximum winding amount storage unit 21. Then, the comparison unit 24 obtains a comparison result regarding the magnitude relationship between the required winding amount and the maximum winding amount.

  The winding amount determination unit 25 is actually conveyed downstream of the printing unit 70 in the conveyance direction before the conveyance direction of the sheet is changed from the direction toward the downstream side in the conveyance direction to the direction toward the upstream side in the conveyance direction. The length of the sheet (actual winding amount), that is, the length of the sheet that is actually conveyed beyond the position facing the head unit 73 of the printing unit 70 is determined. Here, the winding amount determination unit 25 determines the winding amount based on the comparison result by the comparison unit 24. That is, when the comparison unit 24 obtains a comparison result that the required winding amount is equal to or less than the maximum winding amount, the winding amount determination unit 25 determines the actual winding amount as the necessary winding amount, On the other hand, when the comparison unit 24 obtains a comparison result that the required winding amount is longer than the maximum winding amount, the actual winding amount is determined as the maximum winding amount.

  The carry amount detection unit 26 detects the carry amount of the paper based on the number of rotations of the carry roller pair 34 detected by the encoder 36 after the leading edge of the paper is detected by the paper detection sensor 91. That is, the transport amount detection unit 26 detects the length of the paper transported downstream in the transport direction from the position detected by the paper detection sensor 91. As a result, the conveyance amount detection unit 26 is conveyed downstream of the printing unit 70 in the conveyance direction before the sheet conveyance direction is changed from the direction toward the downstream side in the conveyance direction to the direction toward the upstream side in the conveyance direction. The length of the paper can be detected. As will be described later, after the leading edge of the sheet reaches the feed roller pair 35, the sheet is transported by the transport force applied from the feed roller pair 35 instead of the transport force applied from the transport roller pair 34. However, even in this case, the carry amount detection unit 26 always detects the carry amount of the paper based on the number of rotations of the carry roller pair 34.

  The conveyance amount detection unit 26 can detect the conveyance amount of the paper not only when the paper is conveyed toward the downstream side in the conveyance direction but also when the paper is conveyed toward the upstream side in the conveyance direction. . Therefore, when the paper transport direction is changed from the direction downstream in the transport direction to the direction upstream in the transport direction, the transport direction is changed from the transport amount downstream in the transport direction before the transport direction is changed. The leading end position of the sheet can be detected by subtracting the transport amount upstream in the transport direction after being performed.

  The conveyance control unit 27a controls the motors 43a, 31a, 34a, and 35a that drive the rotation shaft 43, the paper feed roller pair 31, the conveyance roller pair 34, and the feeding roller pair 35, thereby supplying the paper from the paper supply unit 40 to the paper. The sheet is conveyed toward the winding unit 80 and the sheet is fed back from the sheet winding unit 80 toward the sheet supply unit 40.

  The printing control unit 27b controls the raising / lowering timing and printing timing of the thermal head 61a of the overcoat unit 60 and the thermal heads 71a to 73a of the printing unit 70. Specifically, when the paper is transported downstream in the transport direction, the print control unit 27b sets the thermal heads 61a and 71a to 73a to the retracted position, and before the paper is fed back upstream in the transport direction, The raising / lowering timing is controlled so that the thermal heads 61a, 71a to 73a are set to the printing positions. In addition, the print control unit 27b prints a plurality of color images included in one order separated by the length of the blank portion on the paper that has been fed back upstream in the transport direction, and finally, The printing timing is controlled so that the image is not printed in an area corresponding to the additional length on the leading end side of the paper than the printed color image. Further, the print control unit 27b controls the overcoat unit 60 so as to overcoat only the area where the color image of the paper is printed.

  The cutting control unit 27c controls the cutting timing at the cutting unit 50 and the timing at which the movable blade 51 is rotated with the fulcrum 50a as a fulcrum. In detail, the cutting control unit 27c detects the conveyance amount detection unit 26 to the upstream side in the conveyance direction after the sheet conveyance direction is changed from the direction toward the downstream in the conveyance direction to the direction toward the upstream in the conveyance direction. Based on the transport amount of the paper, it is detected that the rear end portion of the color image printed most upstream in the transport direction has reached the cutting position by the cutting unit 50, and the rear end portion of the color image is cut. Thus, the cutting unit 50 is controlled. Further, the cutting control unit 27c detects the color image based on the conveyance amount of the sheet upstream in the conveyance direction after the trailing edge of the image is detected by the image detection sensor 90, which is detected by the conveyance amount detection unit 26. Is detected to have reached the cutting position by the cutting unit 50, and the cutting unit 50 is controlled so that the leading end of the color image is cut. Further, the cutting control unit 27c detects the conveyance direction based on the conveyance amount upstream of the conveyance direction after the sheet is cut at the leading end of the color image, which is detected by the conveyance amount detection unit 26. It is detected that the rear end of the color image adjacent on the downstream side has reached the cutting position by the cutting unit 50, and the cutting unit 50 is controlled so that the rear end of the color image is cut. Further, the cutting control unit 27c detects that the leading end area of the sheet has reached the cutting position by the cutting unit 50 when the sheet is being conveyed toward the downstream side in the conveying direction, and the width of the sheet of the movable blade 51 is determined. After adjusting the inclination with respect to the direction, the front end region of the sheet is cut.

  Next, an operation when an image is printed in the printer 1 will be described with reference to FIG. FIG. 7 is a flowchart showing an operation procedure in the printer 1.

  First, the leading end of the sheet unwound by rotating the rotary shaft 43 from the paper winding unit 45 loaded in the paper supply unit 40 is transported only by the transport force applied from the paper feed roller pair 31. (Step S101). When the vicinity of the leading edge of the paper reaches the cutting position by the cutting unit 50, the conveyance by the pair of paper feed rollers 31 is stopped (step S102), and the leading edge of the paper is cut (step S103).

  Here, a state when the leading edge of the sheet is cut will be described with reference to FIG. First, FIG. 8A shows a state in which the vicinity of the leading edge of the paper has reached the cutting position by the cutting unit 50. In this state, the leading edge of the sheet is disposed on the downstream side in the transport direction from the cutting position by the cutting unit. Note that the distance between the leading edge of the paper and the cutting position by the cutting unit at this time varies depending on the shape after the leading edge of the paper is cut. When the rotating member 54 is moved rightward as shown in FIG. 8B, the movable blade 51 is inclined by rotating with the fulcrum 50a as a fulcrum (FIG. 8B). Then it ’s going to rise to the right). As described above, when the movable blade 51 is moved downward in a state inclined with respect to the width direction of the paper, the leading edge of the paper is cut along a straight line inclined with respect to the width direction of the paper. The triangular part is cut off. Then, as shown in FIG. 8C, the leading edge of the sheet is conveyed in a state inclined with respect to the width direction of the sheet.

  Thereafter, the conveyance by the paper feed roller pair 31 is continued until the leading edge of the paper passes through the conveyance roller pair 34 and reaches the paper detection sensor 91 (step S104). Here, when the leading edge of the sheet is detected by the sheet detection sensor 91, a detection signal indicating that the leading edge of the sheet has been detected is transmitted from the sheet detection sensor 91 to the control device 20.

  In this way, when the leading edge of the paper reaches the paper detection sensor 91, the conveyance of the paper is stopped and a standby state is entered (step S105). At this time, when the thermal heads 61a and 71a to 73a are arranged at the print positions, the thermal heads 61a and 71a to 73a are moved to the retracted positions (step S106).

  Thereafter, when an order is received from the operator and the print type and the number of prints of the color image included in one order are input (step S107), the print information is stored as preparation for starting the conveyance of the paper. Based on the information stored in the unit 22, the necessary winding amount corresponding to the one order is calculated by the necessary winding amount calculation unit 23 (step S108). Then, the required winding amount is compared with the maximum winding amount stored in the maximum winding amount storage unit 21 by the comparison unit 24 (step S109). Based on the comparison result, the actual winding amount is determined by the winding amount determination unit 25 (step S110). In this way, after completion of the sheet conveyance preparation, the sheet is conveyed only by the conveyance force applied from the conveyance roller pair 34 (step S111). At this time, both the rotation shaft 43 and the paper feed roller pair 31 of the paper supply unit 40 are rotatable.

  Thereafter, in a state in which the thermal heads 61a and 71a to 73a are disposed at the retracted positions, the leading end of the sheet passes through the overcoat unit 60 and the print unit 70 without performing overcoat and image printing, and the feed roller Until the pair 35 is reached, the conveyance is continued only by the conveyance force applied from the conveyance roller pair 34 (step S112). When the leading edge of the sheet reaches the nipping roller pair 35 and is nipped, the sheet is thereafter conveyed only by the conveying force applied from the feeding roller pair 35 and is wound from the leading edge of the sheet. Are sequentially fed into the storage case 81 of the unit 80 (step S113). At this time, as the paper is fed into the storage case 81, the leading edge of the paper is guided to the inner peripheral surface of the storage case 81 and the take-up rollers 83 a to 83 d, and the paper is wound around the curl in the storage case 81. Therefore, it is wound up. When the leading edge of the paper reaches the feed roller pair 35, the transport roller pair 34 is accompanied by the paper transported by the feed roller pair 35 from the state in which the transport force is applied to the paper by the function of the one-way clutch 34c. It is switched to the state of driven rotation.

  Thereafter, when the sheet having the length of the winding amount determined by the winding amount determination unit 25 is conveyed downstream in the conveyance direction from the printing position by the head unit 73, the winding of the sheet is finished, The conveyance of the sheet from the sheet supply unit 40 toward the sheet take-up unit 80 is stopped (step S114). That is, the conveyance amount of the paper detected by the conveyance amount detection unit 26 based on the number of rotations of the conveyance roller pair 34 detected by the encoder 36 after the leading edge of the paper is detected by the paper detection sensor 91 is taken up. When the winding amount determined by the amount determination unit 25 and the length of the conveyance path in the overcoat unit 60 and the printing unit 70 are added, the conveyance control unit 27a finishes winding the sheet. Then, the conveyance of the sheet to the downstream side in the conveyance direction is stopped. At this time, the rear end portion of the image printed on the most upstream side in the transport direction of the sheet having the winding amount is disposed at the printing position by the head unit 73.

  Then, the thermal head 61a of the overcoat unit 60 and the thermal heads 71a to 73a of the printing unit 70 are simultaneously moved from the retracted position to the printing position (step S115). Thereafter, the sheet is fed back toward the upstream side in the transport direction by the transport force applied from the pair of paper feed rollers 31 and the pair of transport rollers 34 (step S116). Accordingly, at this time, the pair of paper feed rollers 31 and the pair of transport rollers 34 that have been driven to rotate are rotationally driven in the direction of transporting paper toward the upstream side in the transport direction, and the pair of feed rollers 35 The function of the clutch 35c causes the driven rotation. Further, the rotation shaft 43 of the paper supply unit 40 is rotationally driven in a direction to rewind the paper into the magazine case 41.

  Then, while the paper is being fed back toward the upstream side in the conveyance direction, for each color image included in one order, printing corresponding to yellow by the head unit 73, printing corresponding to magenta by the head unit 72, and printing by the head unit 71 Printing corresponding to cyan is sequentially performed. In this way, each color image is printed in the order of yellow, magenta, and cyan, thereby completing the color image (step S117).

  The final image printed closest to the leading edge of the paper is printed by the head unit 73 corresponding to yellow, the head unit 72 corresponding to magenta, and the head unit 71 corresponding to cyan. End in order. Accordingly, the leading end of the sheet passes through the head unit 73, the head unit 72, and the head unit 71 in this order. Here, FIG. 9 shows a state in which the leading end of the sheet passes through the head unit 73 disposed on the most downstream side in the transport direction. 9 (a) to 9 (c) show that when the leading edge of the paper passes the printing position by the thermal head 73a immediately before the leading edge of the paper reaches the printing position by the thermal head 73a, the leading edge of the paper is thermal. The state immediately after passing the printing position by the head 73a is shown.

  In FIG. 9A, the thermal head 73a is in contact with the entire width of the paper. As shown in FIGS. 9B and 9C, when the leading edge of the paper passes the printing position by the thermal head 73a, the leading edge of the paper is in the width direction of the paper as described above. Since the sheet is cut along a straight line inclined, the contact area between the thermal head 73a and the sheet is gradually reduced as the sheet is conveyed.

  FIG. 10 shows temporal changes in the pressing force of the thermal head 73a on the paper in FIGS. 9 (a) to 9 (c). Here, the temporal change in the pressing force of the thermal head 73a against the paper when the leading edge of the paper passes the printing position by the thermal head 73a is shown, but the leading edge of the paper is caused by the thermal heads 71a and 72a. The same applies to the temporal change in the pressing force of the thermal heads 71a and 72a on the paper when it passes the printing position. Since the thermal head 73a is in contact with the entire width of the paper until the leading edge of the paper reaches the printing position by the head unit 73, the pressing force of the thermal head 73a at this time is constant at a predetermined value A. Thereafter, the pressing force of the thermal head 73a gradually decreases, and becomes zero when the thermal head 73a does not contact the paper. Note that the pressing force of the thermal head 73a is proportional to the size of the contact area between the thermal head 73a and the paper.

  Thereafter, the head unit 61 continues to overcoat the surface of the paper on which the color image is printed (step S118). When the printing and overcoating for a plurality of color images are completed while the paper is being sent back upstream in the transport direction, the thermal head 61a of the overcoat unit 60 and the thermal heads 71a to 73a of the printing unit 70 are moved from the printing position. It is simultaneously moved to the retracted position (step S119).

  In the present embodiment, when the necessary winding amount is shorter than the maximum winding amount, reverse feeding to the upstream side in the sheet conveyance direction is started, and simultaneously printing of a color image is started. All of the color images included in the order are printed intermittently so that a margin of a predetermined width is formed between the images. On the other hand, when the necessary winding amount is longer than the maximum winding amount, the reverse feeding to the upstream side in the sheet conveyance direction is started, and at the same time, the printing of the color image is started, and the color image included in one order. Are intermittently printed so that a margin of a predetermined width is formed between the images. That is, as described above, a color image is printed on the paper so that the image areas and the margins are alternately arranged. However, no image is printed in an area corresponding to the additional length for heat radiation near the leading edge of the paper. And in the printing part 70, when there exists an image area | region at the same timing in the position facing at least 2 of the three head parts 71-73, printing is simultaneously performed by those head parts. In addition, the overcoat in the overcoat unit 60 is performed in parallel with the printing of the color image in the print unit 70. In this way, in the printing unit 70 and the overcoat unit 60, a plurality of printable sheets can be printed on the paper having the winding amount determined by the winding amount determination unit 25 or the paper having the maximum winding amount. The color image is printed and overcoated.

  The trailing end of the color image printed on the most upstream side in the transport direction (corresponding to the trailing end of the sheet having the winding amount determined by the winding amount determination unit 25) is formed by the cutting unit 50. When the cutting position is reached, the reverse feeding of the paper is stopped, and the paper is cut at the rear end of the color image (step S120). Note that the timing at which the trailing edge of the color image reaches the cutting position by the cutting unit 50 is detected based on the carry amount detected by the carry amount detection unit 26. After the paper is cut in this way, the paper on which the image upstream of the most upstream color image in the transport direction is not formed (the paper of the length of the winding amount determined by the winding amount determination unit 25) The sheet on the upstream side in the transport direction from the rear end portion is rewound to the sheet supply unit 40.

  Subsequently, when the sheet is reversely fed only by the conveyance force applied from the conveyance roller pair 34 and the rear end portion of the image on the most upstream side in the conveyance direction reaches the detection position by the image detection sensor 90, the image detection sensor 90 controls the control device. A detection signal indicating that the rear end of the image has been detected is transmitted to 20 (step S121). Then, the conveyance amount detection unit 26 detects the trailing edge of the image by the image detection sensor 90, and then detects the amount of the sheet upstream in the conveyance direction based on the number of rotations of the conveyance roller pair 34 detected by the encoder 36. Detect the transport amount. Based on the transport amount, the cutting control unit 27c detects that the leading end of the color image has reached the cutting position by the cutting unit 50. At this time, the reverse feeding of the paper is stopped and the paper is cut at the leading end of the color image (step S122). In this way, the paper from which the leading edge and trailing edge of the color image are cut is stored in the print box 96.

  Each time the paper is cut at the leading edge of the color image, it is determined whether the color image printed on the cut paper is the final image printed closest to the leading edge of the paper. (Step S123). Here, if it is determined that the image is not the final image, the paper is reversely fed again. Then, the conveyance amount detection unit 26 cuts the sheet at the leading end of the color image, and then, based on the number of rotations of the conveyance roller pair 34 detected by the encoder 36, the conveyance amount upstream of the conveyance direction is detected. Detect the transport amount. In the cutting control unit 27c, based on the conveyance amount, the rear end portion of the color image adjacent to the color image whose leading end portion is cut in step S122 on the downstream side in the conveyance direction reaches the cutting position by the cutting unit 50. Detecting that At this time, the reverse feeding of the paper is stopped, and the paper is cut at the trailing edge of the color image (step S124). Then, it returns to step S121 and the process similar to the above is repeated.

  On the other hand, if it is determined that the image is the final image, it is determined whether or not printing of all color images included in one order has been completed (step S125). If it is determined that printing of all the color images included in one order has not been completed, the process returns to step S108 and the same processing as described above is repeated. On the other hand, when it is determined that all the printing of the color images included in one order has been completed, the process ends.

  Note that when it is determined in step S125 that printing of all color images included in one order has not been completed, for example, the comparison unit 24 determines that the required winding amount is longer than the maximum winding amount. This is a case where the winding amount determination unit 25 determines the maximum winding amount as the final winding amount. That is, in this case, printing of the remaining color images that could not be printed on the sheet having the maximum winding amount among the color images included in one order is continued. In this way, the same processing as described above is repeated until all the printing of the color images included in one order is completed.

  As described above, in the printer 1 according to the present embodiment, after the paper is transported in the direction from the paper supply unit 40 to the paper winding unit 80, the upstream side in the transport direction from the overcoat unit 60 and the printing unit 70. A plurality of color images can be printed on a sheet that is fed back toward the upstream side in the transport direction by the transport force of the disposed transport roller pair 34. For this reason, it is possible to print a color image in an area from the front end of the paper portion that is reversely fed after conveyance, and it is possible to suppress deterioration of the image due to load fluctuations during conveyance of the paper. Further, even when printing a plurality of color images on paper, it is only necessary to reciprocate the paper once, and it is only necessary to switch the paper transport direction in the transport mechanism 38 once. Loss can be reduced. As a result, when printing a plurality of color images on paper, the processing capability of the printer 1 can be improved while suppressing image deterioration due to paper waste and load fluctuations during paper transport.

  Further, since the leading edge of the sheet is cut along a straight line inclined with respect to the width direction of the sheet, when the leading edge of the sheet that is fed back to the upstream side in the transport direction passes the print position by the thermal heads 71a to 73a. In addition, the pressing force of the thermal heads 71a to 73a on the paper does not decrease rapidly but gradually decreases. Therefore, when the leading edge of the paper passes through the printing positions of the thermal heads 71a to 73a, even when an image is recorded by another thermal head, image deterioration due to load fluctuations during paper conveyance is prevented. Can be suppressed.

  Further, when the leading end portion of the paper passes through the feeding roller pair 35 (from the state of being pinched by the feeding roller pair 35 to the state of not being pinched), the pressing force of the feeding roller pair 35 on the paper does not rapidly decrease. Gradually becomes smaller. Therefore, even when an image is recorded by the thermal head when the leading edge of the sheet passes through the feed roller pair 35, it is possible to suppress image deterioration due to load fluctuation during conveyance of the sheet.

  Further, before moving the movable blade 51 of the cutting unit 50 in the downward direction, the angle of the movable blade 51 with respect to the width direction of the paper is adjusted by controlling the drive mechanism 57, whereby the paper is moved along the width direction. In addition to being able to cut, the paper can also be cut at an angle. Therefore, since a cutting part for cutting the leading edge of the paper along a straight line inclined with respect to the width direction of the paper and a cutting part for cutting the paper along the width direction are provided in common, the number of parts can be reduced, Manufacturing cost can be reduced.

  In addition, the movable blade 51 of the cutting unit 50 can be rotated by a drive mechanism 57 with a fulcrum 50a disposed at a position corresponding to the outside of the paper transport path as a fulcrum. Therefore, the angle between the movable blade 51 and the paper width direction can be easily adjusted.

  Next, a printer according to a second embodiment of the invention will be described with reference to the drawings. FIG. 11 is a diagram showing a schematic configuration of a printing unit of a printer according to the second embodiment of the present invention. FIG. 12 is a block diagram of the main part of the printer of FIG. 11 and a control device to which these are connected.

  Here, the printer 101 according to the second embodiment is greatly different from the printer 1 according to the first embodiment. In the printer 1, after the sheet is conveyed downstream in the conveyance direction, the upstream side in the conveyance direction. The image is printed while being fed back to the printer 101, but the printer 101 prints the image while the paper is being conveyed downstream in the conveyance direction. In the configuration of the printer 101, the same configurations as those of the printer 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 11, the printing unit 130 of the printer 101 includes a paper supply unit 140 having a rotation shaft 143 that holds a winding unit 145 wound in a roll shape in a housing 130 a, and a paper supply unit 140. And a transport mechanism 138 capable of transporting paper along a transport path curved in one direction from the discharge port 130b toward the discharge port 130b. Further, a cutting unit 150, a printing unit 70, an overcoat unit 60, and a cutting unit 180 are disposed between the paper supply unit 140 and the discharge port 130b from the upstream side to the downstream side of the conveyance path.

  In the present embodiment, the “paper transport direction (transport direction)” means a direction from the paper supply unit 140 toward the discharge port 130b. Further, the “paper front end” and the “image front end” mean the end on the downstream side of the paper or the image transport direction, and the “paper rear end” and “image rear end” The term “edge” means an end portion on the upstream side of the sheet or image in the conveying direction.

  The transport mechanism 138 includes a paper feed roller pair 131 that supplies the paper unrolled from the winding unit 145 of the paper supply unit 140 to the transport roller pair 134, a cutting unit 150, a printing unit 70, an overload on the downstream side thereof. A conveyance roller pair 134 that can be conveyed so as to sequentially pass through the coat unit 60 and the cutting unit 180 is provided. The conveyance roller pair 134 is connected to a motor 134a (see FIG. 12) controlled by the conveyance control unit 127a (see FIG. 12), and can be driven to rotate.

  The cutting unit 150 is disposed on the upstream side in the transport direction with respect to the transport roller pair 134. The cutting unit 150 includes a moving blade 151 disposed on the left side of the transport path and a fixed blade 152 disposed on the right side of the transport path. Therefore, when the cutting control unit 127c controls the drive mechanism 153 and moves the moving blade 151 in the right direction in a state where the sheet is disposed at the cutting position by the cutting unit 150, the movement of the moving blade 151 and the fixed blade 152 The paper is cut by the interaction. As described above, the cutting unit 150 has the same configuration as the cutting unit 50 of the first embodiment, and the moving blade 151 is controlled by controlling the drive mechanism 157 before moving the moving blade 151 in the right direction. By adjusting the angle of the sheet with respect to the width direction, the sheet can be cut along the width direction, and the sheet can be cut obliquely.

  The cutting unit 180 is disposed on the downstream side of the overcoat unit 60 in the transport direction. The cutting unit 180 includes a rolling cutter 181 disposed above the conveyance path, a fixed blade 182 disposed below the conveyance path, and a chip box 183. Therefore, when the cutting control unit 127c controls the drive mechanism 183 and moves the rolling cutter 181 along the width direction of the paper while rotating the paper while the paper is arranged at the cutting position by the cutting unit 180, the rolling cutter 183 is rotated. The sheet is cut by the interaction between the 181 and the fixed blade 182.

  In addition, a print tray 196 that receives paper discharged from the housing 130a is provided in front of the housing 130a. The print tray 196 receives a sheet (print) on which each color image printed by the cutting unit 180 is printed after the color image is printed in the printing unit 70 and the overcoat unit 60 is overcoated. Is.

  As shown in FIG. 12, the control device 120 includes a motor 143 a that drives the rotation shaft 143 of the paper supply unit 140, motors 131 a and 134 a that drive the paper feed roller pair 131, the transport roller pair 134, and the transport roller pair. Encoder 36 for detecting the number of rotations 134, driving mechanisms 153 and 157 for the moving blade 151 of the cutting unit 150, driving mechanism 183 for the rolling cutter 181 of the cutting unit 180, and thermal heads for the overcoat unit 60 and the printing unit 70. The lifting mechanisms 61f and 71f to 73f of 61a and 71a to 73a and the drivers 61g and 71g to 73g, the image detection sensor 90, the paper detection sensor 91, and the operation unit 10 are respectively connected.

  The transport control unit 127a controls the motors 143a, 131a, and 134a that drive the rotating shaft 143, the paper feed roller pair 131, and the transport roller pair 134 to transport the paper from the paper supply unit 140 toward the discharge port 130b. . The print control unit 127b controls the elevation timing and print timing of the thermal head 61a of the overcoat unit 60 and the thermal heads 71a to 73a of the print unit 70. The cutting control unit 127c controls the cutting timing at the cutting unit 150, the timing for rotating the movable blade 151 around the fulcrum 150a, and the cutting timing at the cutting unit 180.

  Next, an operation when an image is printed in the printer 101 will be described with reference to FIG. FIG. 13 is a flowchart showing an operation procedure in the printer 101.

  First, the leading end of the sheet unwound by rotating the rotary shaft 143 from the paper winding unit 145 loaded in the paper supply unit 140 is transported only by the transport force applied from the paper feed roller pair 131. (Step S201). Then, the conveyance by the paper feed roller pair 131 is continued until the leading edge of the paper passes through the conveyance roller pair 134 and reaches the paper detection sensor 91 (step S202).

  In this way, when the leading edge of the paper reaches the paper detection sensor 91, the conveyance of the paper is stopped and a standby state is entered (step S203). Thereafter, when an order is received from the operator, and the color image print type and the number of prints are input (step S204), the paper is transported only by the transport force applied from the transport roller pair 134 (step S204). Step S205). At this time, both the rotation shaft 143 and the paper feed roller pair 131 of the paper supply unit 140 are rotatable.

  For each color image, the paper corresponding to yellow is printed by the head unit 73, the print corresponding to magenta is printed by the head unit 72, and the print corresponding to cyan is printed by the head unit 71 while the paper is conveyed toward the downstream side in the conveyance direction. It is done sequentially. In this way, for each color image, printing is performed in the order of yellow, magenta, and cyan, thereby completing the color image (step S206). Thereafter, the head unit 61 continues to overcoat the surface of the paper on which the color image is printed (step S207).

  When the trailing edge of the sheet reaches the cutting position by the cutting unit 150, the conveyance by the conveying roller pair 134 is stopped (step S208), and the trailing edge of the sheet is cut (step S209). Here, the state when the trailing edge of the sheet is cut is the same as the state when the leading edge of the sheet is cut in the first embodiment, as shown in FIG.

  When the leading end of the color image printed on the most downstream side in the transport direction reaches the cutting position by the cutting unit 150, the transport of the paper is stopped and the paper is cut at the leading end of the color image (step S210).

  Subsequently, when the sheet is transported only by the transport force applied from the pair of transport rollers 34 and the leading end of the image on the most downstream side in the transport direction reaches the detection position by the image detection sensor 90, the image detection sensor 90 transfers to the control device 120. On the other hand, a detection signal indicating that the leading end of the image has been detected is transmitted (step S211). Then, the cutting control unit 127c detects that the rear end portion of the color image has reached the cutting position by the cutting unit 150. At this time, the conveyance of the paper is stopped, and the paper is cut at the rear end of the color image (step S212). In this way, the paper from which the leading edge and trailing edge of the color image have been cut is stored in the print tray 196.

  Each time the paper is cut at the trailing edge of the color image, it is determined whether the color image printed on the cut paper is the final image printed closest to the trailing edge of the paper (Step S213). If it is determined that the image is the final image, the process ends. On the other hand, if it is determined that the image is not the final image, the sheet is conveyed again. Then, the cutting control unit 127c detects that the leading end portion of the color image adjacent to the color image whose rear end portion has been cut in step S212 on the upstream side in the transport direction has reached the cutting position by the cutting unit 150. At this time, the conveyance of the sheet is stopped, and the sheet is cut at the leading end of the color image (step S214). Then, it returns to step S211 and the process similar to the above is repeated.

  As described above, in the printer 101 according to the present embodiment, the rear end of the sheet is cut along a straight line inclined with respect to the width direction of the sheet, as in the first embodiment. When the trailing edge of the sheet conveyed downstream passes through the print positions of the thermal heads 71a to 73a, the pressing force of the thermal heads 71a to 73a on the sheet is gradually reduced rather than abruptly reduced. Accordingly, when the rear end portion of the sheet passes through the printing position by the thermal heads 71a to 73a, even when an image is recorded by another thermal head, the image is deteriorated due to the load fluctuation during the conveyance of the sheet. Can be suppressed.

  Further, when the trailing edge of the sheet passes through the pair of paper feed rollers 131 and the pair of transport rollers 134 (from the state of being sandwiched by the pair of paper feed rollers 131 or the pair of transport rollers 134), the paper feed rollers The pressing force of the pair 131 or the conveyance roller pair 134 against the sheet does not decrease rapidly but gradually decreases. Accordingly, even when an image is recorded by the thermal head when the trailing edge of the paper passes the paper feed roller pair 131 or the conveyance roller pair 134, the image is deteriorated due to the load fluctuation during the conveyance of the paper. Can be suppressed.

  The cutting unit 150 can cut the trailing edge of the sheet along a straight line inclined with respect to the width direction of the sheet, and can cut the sheet along the width direction. Therefore, the number of parts can be reduced and the manufacturing cost can be reduced.

  Further, since the printer 101 includes the cutting unit 180 disposed on the downstream side of the printing unit 70, the rear end of the sheet after the color image is printed can be cut along the width direction. .

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various design changes can be made as long as they are described in the claims. For example, in the first embodiment described above, the sheet is fed back toward the upstream side in the transport direction by the transport force of the transport roller pair 34 disposed on the upstream side in the transport direction with respect to the overcoat unit 60 and the print unit 70. However, the present invention is not limited to this. Therefore, a color image may be printed on a sheet that is fed back toward the upstream side in the transport direction by the transport force of the transport roller pair disposed on the downstream side in the transport direction from the overcoat unit 60 and the print unit 70.

  In the first and second embodiments described above, the leading edge or the trailing edge of the sheet can be cut along a straight line inclined with respect to the width direction of the sheet, and the sheet is aligned along the width direction. Cutting sections 50 and 150 are provided. The cutting section is capable of cutting along the straight line in which the leading edge or the trailing edge of the sheet is inclined with respect to the width direction of the sheet, and the sheet along the width direction thereof. And a cutting part capable of being cut off may be provided separately.

  Therefore, for example, as shown in FIGS. 15A and 15B, the movable blade 251 and the fixed blade 252 that can cut the leading edge or the trailing edge of the sheet along a straight line inclined with respect to the width direction of the sheet. And a cutting unit 280 having a movable blade 281 and a fixed blade 282 capable of cutting the paper along the width direction thereof.

  In the first and second embodiments described above, the leading edge or the trailing edge of the sheet is inclined with respect to the width direction of the sheet by the moving blade 51 that is in a state of rising to the right. However, the leading edge or the trailing edge of the sheet may be cut along a straight line inclined with respect to the width direction of the sheet by the movable blade 51 that is in a state of rising to the left. Further, the angle between the movable blade 51 and the paper width direction can be changed.

  Further, in the first embodiment described above, when a color image is printed while the paper is fed back upstream in the transport direction, the pair of feed rollers 35 (nipping the paper downstream in the transport direction of the printing unit 70) ( In the second embodiment described above, when a color image is printed while the paper is being transported downstream in the transport direction, the paper is placed upstream in the transport direction of the printing unit 70. The paper feeding roller pair 131 and the conveying roller pair 134 (pressure roller pair) to be sandwiched are provided, but there may be no roller pair having the function of these pressure roller pairs.

  Further, as in the first and second embodiments described above, when there is a roller pair having the function of the pressure roller pair, one or more images capable of recording an image without contacting the paper. Even if the printer has a recording head or a printer that has only one image recording head and can form a black and white image, the same effects as described above can be obtained.

  In the first and second embodiments described above, the movable blades 51 and 151 of the cutting units 50 and 150 rotate around the fulcrums 50a and 150a arranged at positions corresponding to the outside of the paper conveyance path. Although possible, the configuration of the cutting section that can cut along the straight line in which the leading edge or the trailing edge of the sheet is inclined with respect to the width direction of the sheet can be changed.

  Further, in the first embodiment described above, in the thermal sublimation printer 1, the color image is printed by the three head portions 71 to 73 that come into contact with the paper that is the recording medium, but the color image can be recorded. If the printer is a simple printer, the configuration of the image recording unit is not limited to this. Therefore, it may be a thermal printer (including a thermal transfer system and a thermal recording system) having a head that comes into contact with a recording medium, and has, for example, an inkjet head, a FOCRT (Fiber Optic Cathode-Ray-Tube), a laser light source, etc. And a printer capable of recording a color image without contacting the recording medium. Further, the image recording unit does not necessarily have a plurality of image recording heads, and may have only one image recording head capable of recording a color image. Therefore, for example, it has three inkjet heads each having nozzles capable of ejecting yellow, magenta and cyan inks, and these heads reciprocate in a direction crossing the recording medium conveyance direction to record a color image. Or a single inkjet head having nozzles capable of discharging yellow, magenta, and cyan inks, and the head reciprocates in a direction intersecting the recording medium conveyance direction. A printer that records a color image may be used.

1 is an external perspective view of a printer according to a first embodiment of the present invention. FIG. 2 is a diagram illustrating a schematic configuration of a printing unit of the printer of FIG. 1. It is a figure showing a motion of the conveyance roller pair of the printer of FIG. 1, and a sending roller pair. It is a figure which shows schematic structure of the cutting part of the printer of FIG. It is a block diagram about the principal part of the printer of FIG. 1, and the control apparatus to which these were connected. It is a figure which shows a mode when the several color image contained in 1 order is printed in the front-end | tip part vicinity of a paper. 3 is a flowchart showing an operation procedure in the printer of FIG. 1. It is a figure which shows a mode when the front-end | tip of a paper is cut | disconnected. FIG. 6 is a diagram illustrating a state when a leading end portion of a sheet passes through a head portion that is disposed on the most downstream side in the transport direction. The change with time of the pressing force of the thermal head on the paper is shown. It is a figure which shows schematic structure of the printing part of the printer which concerns on the 2nd Embodiment of this invention. It is a block diagram about the principal part of the printer of FIG. 10, and the control apparatus to which these were connected. 11 is a flowchart showing an operation procedure in the printer of FIG. 10. It is a figure which shows a mode when the rear end of a paper is cut | disconnected. It is a figure which shows an example of the other structure of a cutting part.

Explanation of symbols

1, 101 Thermal printer (printer)
DESCRIPTION OF SYMBOLS 10 Operation part 20 Control apparatus 21 Maximum winding amount memory | storage part 22 Print information storage part 23 Required winding amount calculation part 24 Comparison part 25 Winding amount determination part 26 Conveyance amount detection part 27a, 127a Conveyance control part (conveyance control means)
27b, 127b Print control unit (image recording control means)
27c, 127c cutting control unit (cutting control means)
30 Print unit 34 Conveying roller pair 36 Encoder 38, 138 Conveying mechanism 40 Paper supply unit (supply unit)
50, 150 Cutting part (cutting mechanism)
51,151 Moving blade (cutting blade)
52,152 Fixed blade (cutting blade)
58 Rotation drive mechanism 60 Overcoat part 61a Thermal head 70 Printing part (image recording part)
71a to 73a Thermal head (image recording head)
80 Paper winding unit 91 Paper detection sensor 95 Discharge unit 250 Cutting unit (first cutting unit)
280 cutting part (second cutting part)

Claims (18)

A supply unit storing a recording medium;
An image recording unit having a plurality of image recording heads capable of recording a color image while being in contact with the recording medium;
A transport mechanism capable of transporting a recording medium in a first direction from the supply unit to the image recording unit and a second direction opposite to the first direction while facing the plurality of image recording heads. When,
A cutting mechanism that is disposed between the supply unit and the image recording unit and capable of cutting a recording medium conveyed by the conveyance mechanism;
The leading end of the recording medium is cut along a straight line inclined with respect to the width direction of the recording medium before the leading end of the recording medium reaches the image recording unit by transporting the recording medium in the first direction. Cutting control means for controlling the cutting mechanism;
The transport mechanism so that the recording medium is transported in the second direction after being transported in the first direction until the leading end of the recording medium reaches a position away from the image recording unit in the first direction. Transport control means for controlling
And image recording control means for controlling the image recording unit so that a color image is recorded by the image recording unit on the recording medium conveyed in the second direction by the conveyance mechanism. And printer.   2. The conveyance mechanism according to claim 1, wherein the conveyance mechanism can convey the recording medium in the second direction by applying a conveyance force to the recording medium between the supply unit and the image recording unit. The printer described. A supply unit storing a recording medium;
An image recording unit having an image recording head capable of recording an image;
A transport mechanism capable of transporting a recording medium in a first direction from the supply unit toward the image recording unit and a second direction opposite to the first direction while facing the image recording head;
A cutting mechanism that is disposed between the supply unit and the image recording unit and capable of cutting a recording medium conveyed by the conveyance mechanism;
A pressure roller pair disposed downstream of the image recording unit and capable of sandwiching a recording medium;
The leading end of the recording medium is cut along a straight line inclined with respect to the width direction of the recording medium before the leading end of the recording medium reaches the image recording unit by transporting the recording medium in the first direction. Cutting control means for controlling the cutting mechanism;
The transport mechanism so that the recording medium is transported in the second direction after being transported in the first direction until the leading end of the recording medium reaches a position away from the image recording unit in the first direction. Transport control means for controlling
And image recording control means for controlling the image recording unit so that an image is recorded by the image recording unit on a recording medium conveyed in the second direction by the conveyance mechanism. Printer.   4. The conveyance mechanism according to claim 3, wherein the conveyance mechanism is capable of conveying the recording medium in the second direction by applying a conveyance force to the recording medium between the supply unit and the image recording unit. The printer described.   The printer according to claim 3, wherein the image recording unit includes an image recording head capable of recording an image while being in contact with a recording medium.   The printer according to claim 3, wherein the image recording unit includes a plurality of image recording heads and is capable of recording a color image. The cutting mechanism is
A first cutting portion capable of cutting along a straight line in which the front end of the recording medium is inclined with respect to the width direction of the recording medium;
The printer according to claim 1, further comprising a second cutting unit capable of cutting the recording medium along a width direction thereof. The cutting mechanism is
2. The recording medium according to claim 1, further comprising a cutting portion capable of cutting the front end of the recording medium along a straight line inclined with respect to the width direction of the recording medium and capable of cutting the recording medium along the width direction. The printer of any one of -6. The cutting part is
A cutting blade that is rotatable about a predetermined position outside the conveyance path of the recording medium as a fulcrum;
The printer according to claim 8, further comprising a rotation drive mechanism that rotates the cutting blade around the predetermined position as a fulcrum. A supply unit storing a recording medium;
An image recording unit having a plurality of image recording heads capable of recording a color image while being in contact with the recording medium;
A transport mechanism capable of transporting a recording medium in a direction from the supply unit to the image recording unit while facing the plurality of image recording heads;
A first cutting mechanism disposed between the supply unit and the image recording unit and capable of cutting a recording medium conveyed by the conveyance mechanism;
Before the trailing edge of the recording medium reaches the image recording unit by being conveyed, the trailing edge of the recording medium is cut along a straight line inclined with respect to the width direction of the recording medium. Cutting control means for controlling the first cutting mechanism;
A transport control means for controlling the transport mechanism;
A printer comprising: an image recording control unit that controls the image recording unit so that a color image is recorded by the image recording unit on a recording medium conveyed by the conveyance mechanism.   The printer according to claim 10, further comprising a second cutting mechanism that is disposed downstream of the image recording unit and capable of cutting a recording medium conveyed by the conveyance mechanism. A supply unit storing a recording medium;
An image recording unit having an image recording head capable of recording an image;
A transport mechanism capable of transporting a recording medium in a direction from the supply unit to the image recording unit while facing the image recording head;
A first cutting mechanism disposed between the supply unit and the image recording unit and capable of cutting a recording medium conveyed by the conveyance mechanism;
A pressure roller pair disposed between the first cutting mechanism and the image recording unit;
Before the recording medium is conveyed and the trailing edge of the recording medium reaches the pressure roller pair, the trailing edge of the recording medium is cut along a straight line inclined with respect to the width direction of the recording medium. Cutting control means for controlling the first cutting mechanism;
A transport control means for controlling the transport mechanism;
A printer comprising: an image recording control unit that controls the image recording unit so that the image recording unit records an image on a recording medium conveyed by the conveyance mechanism.   The printer according to claim 12, further comprising a second cutting mechanism that is disposed on the downstream side of the image recording unit and capable of cutting a recording medium conveyed by the conveyance mechanism.   The printer according to claim 12, wherein the image recording unit includes an image recording head capable of recording an image while being in contact with a recording medium.   The printer according to claim 12, wherein the image recording unit includes a plurality of image recording heads and is capable of recording a color image. The first cutting mechanism includes:
A first cutting part capable of cutting along a straight line whose rear end is inclined with respect to the width direction of the recording medium;
The printer according to claim 10, further comprising a second cutting unit capable of cutting the recording medium along a width direction thereof. The first cutting mechanism includes:
The rear end of the recording medium can be cut along a straight line inclined with respect to the width direction of the recording medium, and further includes a cutting portion capable of cutting the recording medium along the width direction. The printer according to any one of 10 to 15. The cutting part is
A cutting blade that is rotatable about a predetermined position outside the conveyance path of the recording medium as a fulcrum;
The printer according to claim 17, further comprising a rotation drive mechanism that rotates the cutting blade around the predetermined position as a fulcrum.

Images