JP2007276922A - Paper carrying device for printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To correct inclination of a printing face with respect to recording paper by using a simple mechanism without damaging the recording paper. <P>SOLUTION: In this paper carrying device for a printer, recording paper 1 is sandwiched between and carried by a grip roller 2 for transmitting carrying force to the recording paper 1 and a pinch roller 3 arranged opposing to the grip roller 2 and having pressure contact with the recording paper 1, and images are recorded on the recording paper 1. The paper carrying device for the printer is provided with a detector for detecting shift of the central position in the width direction of the recording paper 1 and with a pressure contact force adjusting means for making the pressure contact force to bring the recording paper 1 into pressure contact with the grip roller 2 by the pinch roller 3 differentiate between both side end parts in the recording paper width direction of the pinch roller 3. In accordance with output of the detector, the pressure contact force adjusting means is adjusted, so as to correct the misalignment of the central position of the recording paper 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a paper transport device for a printer capable of correcting the inclination of a marking screen with respect to a recording paper, and can be applied to, for example, a paper transport device for a color thermal printer.

  According to a color thermal printer that performs thermal sublimation recording, a roll paper-like recording paper and a single ink ribbon coated with YMC's three primary colors (in some cases, an overcoat) are supplied and the thermal head vaporizes the ink. Thus, the image is transferred to the recording paper. The recording paper is sandwiched between a grip roller and a pinch roller having fine projections formed on the surface by etching or the like. The recording paper is pierced into the minute protrusions of the grip roller, and the recording paper is conveyed by the rotation of the grip roller. In the transport direction, after printing the first color of ink, the sheet is returned to the original position, and the recording sheet is fed and returned for each color printing so that the next color is printed. When all the ink has been transferred, the recording sheet is sent out by a predetermined length, and cut and discharged according to a predetermined dimension.

  In the printer device having such a configuration, when continuous printing is continued, the recording paper meanders or skews. Also, when the recording paper is set between the grip roller and the pinch roller, the recording paper meanders or skews depending on how it is attached. For this reason, the stamp screen is slanted with respect to the recording paper, which impairs the beauty. Further, if printing is continued in such a state, there is a risk of causing paper jam.

  In order to solve such a problem, in Patent Document 1, a regulation guide is provided in the roll paper holding mechanism portion to prevent skew, and in Patent Document 2, a groove that matches the sheet width is provided in the platen roller. The skew is prevented. In Japanese Patent Application Laid-Open No. H11-260260, there is also one in which the platen facing the head is moved according to the inclination of the recording paper.

Japanese Patent Laid-Open No. 9-255196 JP-A-5-330105 JP 2000-79732 A

However, in Patent Document 1, when it is attempted to prevent the skew of the roll paper, the paper side edge is rubbed by the paper regulation guide, and the paper side edge is fluffed, bent, or the like, resulting in poor appearance. There was a point. Moreover, in patent document 2, when using paper of a different width | variety, a platen roller must be replaced | exchanged according to it and it becomes an effort. Furthermore, in Patent Document 3, there is a problem that the apparatus configuration becomes large because the mechanism moves the direction of the platen roller and the head simultaneously.
The present invention has been made to solve the above-described problems, and is intended to correct the inclination of the mark screen with respect to the recording paper by a simple mechanism without damaging the recording paper.

  A paper transport device for a printer according to the present invention sandwiches and feeds a recording paper by a grip roller that transmits a transport force to the recording paper and a pinch roller that is disposed opposite to the grip roller and presses the recording paper. In a paper transport device of a printer that records an image on a recording paper, a detector that detects a center position shift in the width direction of the recording paper, and a pressure contact force that the pinch roller presses the recording paper against the grip roller is the pinch. A pressure contact force adjusting means for making a difference between both ends of the roller in the recording paper width direction, and adjusting the pressure contact force adjusting means according to the output of the detector so as to correct the center position deviation of the recording paper. It is a thing.

  Further, the pressing force adjusting means is provided with a pressing force adjusting spring that applies an adjusting force in a direction opposite to the pressing direction of the pinch roller that presses the recording paper, at both ends of the pinch roller, and the both pressing force adjusting springs are provided. By moving the connecting member to be connected along the connecting member, a difference is made in the adjusting force of the both pressure contact force adjusting springs.

  According to the paper transport device of the printer of the present invention, the center position deviation of the recording paper can be corrected by a simple mechanism without damaging the recording paper, and the deviation or inclination of the mark screen with respect to the recording paper can be corrected. it can.

  The pressure contact force adjusting means includes a pressure contact force adjusting spring that applies an adjustment force in a direction opposite to the pressure contact direction of the pinch roller that presses the recording paper at each end of the pinch roller, and connects the pressure contact force adjusting springs. By moving the member along the connecting member, the adjustment force of the two pressure contact force adjustment springs is made different, so the pressure contact force against the recording paper is adjusted at both ends of one pinch roller. Moreover, since the adjustment force is adjusted by moving the connecting member that connects the two pressure contact force adjustment springs, the adjustment force at both ends can be easily adjusted.

Embodiment 1 FIG.
FIG. 1 is a structural perspective view showing the main part of a paper conveying apparatus for a printer according to Embodiment 1 of the present invention. In FIG. 1, the recording paper 1 is transported by sandwiching the recording paper 1 between the grip roller 2 and the pinch roller 3 and rotating the grip roller 2. The recording paper 1 is fed out from a roll-shaped sheet holding mechanism (not shown) arranged upstream in the traveling direction (the arrow direction in the figure). The grip roller 2 is rotated by a driving force of a stepping motor (not shown). The pinch roller 3 is connected at its shaft end to the first support member 5 through a bearing so as to be rotatable by a shaft 5a, and freely rotates in the form of being driven by the grip roller 2 when in contact with the paper. can do. Although not shown, a head for recording an image on the recording paper 1 and a platen roller facing the head are arranged on the downstream side of the recording paper 1.

  The second support member 4 is rotatably supported at one end of the first support member 5 by a pin 5b supported by a printer housing (not shown). A pin 5c provided at one end of the second support member 4 and a groove 10a provided in the cam 10 are supported so that the second support member 4 can be rotated by the pin 5b. A first spring 6 is stretched between the other end of the second support member 4 and the other end of the first support member 5. The left and right cams 10 are integrally connected via the camshaft 11, and the camshaft 11 is supported by the housing so as to be able to rotate. By rotating the cam 10 counterclockwise toward the paper surface, the second support member 4 supported by the pin 5b via the pin 5c is tilted, and the first spring 6 is pulled and attached to the first support member 5. The pinch roller 3 is lowered and the pinch roller 3 contacts the recording paper by applying a pressing force. The cam 10, the second support member 4, the first support member 5 and the first spring 6 are arranged symmetrically. The pressing force applied to the paper is applied substantially uniformly along one axis of the pinch roller 3 by these members.

  On the other hand, one end of the second spring 7 is hooked in a hole provided in the first support member 5, and a metal wire 8 is attached to the other end of the second spring 7. The direction of the metal wire 8 is changed via a pulley 9 and is connected to a metal wire (connecting member) 8 extending from the opposite side via a flat plate 12. The pulley 9 is rotatably supported on a shaft supported by the housing. The flat plate 12 is fixed to the metal wire 8. The position of the flat plate 12 is stopped when the force of the second springs 7 becomes equal. The direction of the adjustment force applied to the recording paper 1 by the pinch roller 3 by the second spring 7 acts in the direction of weakening the pressing force applied to the recording paper 1 by the first spring 6. Therefore, the adjustment force applied to the recording paper 1 by the second spring 7 must be smaller than the pressure contact force applied to the recording paper 1 by the first spring 6.

  Next, when the U-shaped member 13 fixed to the flat plate 12 is operated in the right direction toward the traveling direction of the recording paper 1 by the driving force from the driving device (motor M) 31, as shown in the figure, The second spring 7 contracts, and the left second spring 7 extends. Thereby, the force with which the pinch roller 3 presses the paper is strong on the right side of the recording paper 1 and weak on the left side, and the adhesion between the grip roller 2 and the recording paper 1 is large on the right side and small on the left side. As a result, the amount of fine protrusions provided on the grip roller 2 increases on the right side and decreases on the left side. As a result, the conveyance amount of the recording paper 1 per one rotation of the grip roller 2 is small on the right side and large on the left side, and the paper skews to the right side. In this way, if necessary, the recording paper 1 can be deliberately skewed. Note that the pressing force adjusting means for making a difference in the pressing force with which one pinch roller 3 presses the recording paper 1 at both ends in the recording paper width direction of the pinch roller 3 is the second spring 7, pulley 9, metal wire. 8, a flat plate 12, a U-shaped member 13, a drive device 31, and a control unit 32.

Here, the positions of the both ends of the recording paper 1 are determined by the difference between the electrical signals from the sensors 18 and 18 and the reference voltage difference output from the sensors 18 and 18 that are output with a certain amount of light shielded at the left and right ends of the recording paper 1. Detect center position deviation. Both sensors 18 and 18 are installed at positions equidistant from the set center of the recording paper. The U-shaped member is encoded while the drive unit (motor M) 31 is encoded from the control unit 32 so that the recording paper 1 is sequentially skewed in the reverse direction in accordance with the center position shift amount thus detected. By moving 13, the deviation of the center position of the recording paper 1 can be corrected, and the inclination of the marking screen relative to the recording paper can be corrected.
If correction of the center position deviation (skew) is performed during each color print, the left and right positions of the recording paper 1 differ between the first color and the other colors, resulting in color deviation. Therefore, the correction of the center position deviation and the inclination must be performed during feeding of the recording paper 1 before cutting the recording paper 1 or feeding before printing the first color.

Embodiment 2. FIG.
FIG. 2 is a block diagram showing the main part of the paper transport device of the printer according to the second embodiment. In addition, the same code | symbol shows the same or an equivalent part throughout each figure, and uses description partially. A link mechanism is used as a mechanism for connecting and pulling the second springs 7 and 7 together. An L-shaped member 19 is provided at the tip of each second spring 7, and the L-shaped members 19 and 19 are connected by a connecting rod (connecting member) 21. The L-shaped member 19 is rotatably supported by a pin 19a supported by the housing. In order to move the connecting rod 21 in the axial direction of the connecting rod 21, a rack and a pinion 20 are provided. The rack is fixed to the connecting rod 21 and the drive shaft of the pinion is supported on the housing. When the connecting rod 21 is slid through the control unit 32 and the driving device 31 in accordance with information from the sensors 18, 18, the L-shaped member 19 rotates around the fulcrum 19a. As a result, the amount of extension of the second springs 7 and 7 can be changed left and right. As described above, in the same manner as in the first embodiment, the center position deviation of the recording paper 1 is corrected by sequentially correcting the recording paper 1 in the opposite direction to the center position deviation direction, and the inclination of the mark screen with respect to the recording paper is corrected. be able to.

Embodiment 3 FIG.
FIG. 3 is a structural perspective view showing the main part of the paper conveying apparatus of the printer according to the third embodiment.
The difference from FIG. 1 is that the cam 10 is not connected by the camshaft 11, and there is no second spring 7, pulley 9, metal wire 8, flat plate 12, and U-shaped member 13. Although the cam 10, the first support member 5, the second support member 4, and the first spring 6 are provided symmetrically, the cam 10 is driven separately on the left and right. Reference numeral 14 denotes a driving motor, which transmits a driving force to the cam 10 via a worm gear. The opening angle of the second support member 4 by the cam 10 can be set individually on the left and right sides, and the pressing force that presses against the paper from the pinch roller 3 can be changed on the left and right. In this apparatus, the pinch roller 3 presses the recording paper 1 against the grip roller 2 and also has a function of a pressing force adjusting means for making a difference between the press contact forces at both ends of the pinch roller 3 in the recording paper width direction. .

  In FIG. 3, when the opening angle of the second support member 4 is set to be right> left toward the recording sheet traveling method, the recording sheet 1 is skewed to the right. As in the first embodiment, the center position deviation is corrected sequentially from the center position deviation in the opposite direction according to the center position deviation amount detected by, for example, the photo sensors 18 and 18 or the linear sensor. In addition, by driving one drive motor 14 with respect to the other drive motor 14 via the control unit 32 and the drive device 31, the center position deviation of the recording paper 1 can be corrected.

Embodiment 4 FIG.
FIG. 4 is a block diagram showing the main part of the paper transport device of the printer according to the fourth embodiment. A piezoelectric element 17 is provided instead of the second spring 7 of the first embodiment. One end of the piezoelectric element 17 is fixed to one end of the second support member 4. A voltage is applied to the piezoelectric element 17 in accordance with the amount of center position deviation detected by the photosensors 18, 18, and a mechanical driving force is applied to one end of the second support member 4. Therefore, the rotation is added by the piezoelectric element 17 in addition to the rotation of the second support member 4 by the cam 10. By driving the piezoelectric element 17 via the control unit 32 and the driving device 31 so as to correct the center position deviation in the reverse direction sequentially from the center position deviation, the center position deviation of the recording paper 1 can be corrected.

Embodiment 5 FIG.
FIG. 5 is a block diagram showing the main part of the paper transport device of the printer according to the fifth embodiment. Instead of the second spring 7 of the first embodiment, one or both first support members 5 are provided with electromagnetic solenoids 16 via connecting members 15. The adjusting force by the electromagnetic solenoid 16 applied to the end of the pinch roller 3 is applied in the direction opposite to the pressing direction of the pinch roller that presses the recording paper by the first spring 6. The electromagnetic solenoid 16 is urged via the control unit 32 and the driving device 31 according to the center position deviation amount detected by the photosensors 18 and 18 to apply an adjustment force to the first support member 5, and the center of the recording sheet. Correct misalignment

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a structural perspective view showing a main part of a paper transport device for a printer according to Embodiment 1 of the present invention. FIG. 10 is a configuration diagram illustrating a main part of a paper transport device of a printer according to a second embodiment. FIG. 10 is a structural perspective view showing a main part of a paper transport device of a printer according to a third embodiment. FIG. 10 is a configuration diagram illustrating a main part of a paper transport device of a printer according to a fourth embodiment. FIG. 10 is a configuration diagram illustrating a main part of a paper transport device of a printer according to a fifth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Recording paper 2 Grip roller 3 Pinch roller 4 2nd support member 5 1st support member 5a Axis 5b Pin 5c Pin 6 1st spring 7 2nd spring 8 Metal wire 9 Pulley 10 Cam 10a Groove 11 Cam shaft 12 Flat plate 13 Character-shaped member 14 Motor 15 Connecting member 16 Electromagnetic solenoid 17 Piezoelectric element 18 Sensor 19 L-shaped member 19a Pin 20 Rack & pinion 21 Connecting rod 31 Drive device 32 Control unit

Claims (5)

A printer for recording and recording an image on a recording sheet by sandwiching and conveying the recording sheet between a grip roller that transmits a conveying force to the recording sheet and a pinch roller that is disposed opposite to the grip roller and presses the recording sheet. In the paper transport device,
A detector that detects a center position deviation in the width direction of the recording paper, and a pressure contact force that makes a difference between the press contact force of the pinch roller pressing the recording paper against the grip roller at both ends of the pinch roller in the recording paper width direction A printer paper transport apparatus comprising: an adjusting means, wherein the press contact force adjusting means is adjusted in accordance with an output of the detector to correct a center position deviation of the recording paper.   The pressure contact force adjusting means is provided with a pressure contact force adjusting spring that applies an adjustment force in a direction opposite to the pressure contact direction of the pinch roller that presses the recording paper, at both ends of the pinch roller, and connects the pressure contact force adjusting springs. 2. A paper conveying apparatus for a printer according to claim 1, wherein the connecting member is moved along the connecting member so as to make a difference in the adjusting force of the two pressure contact force adjusting springs. The pressure contact force adjusting means applies a pressure contact force that presses the recording paper against the grip roller by the pinch roller independently at both ends in the recording paper width direction of the pinch roller,
2. A paper conveying apparatus for a printer according to claim 1, wherein said press contact adjusting means is adjusted in accordance with an output of said detector to correct a center position deviation of the recording paper. The pressing force adjusting means is a piezoelectric element that applies an adjusting force for adjusting the pressing force of the pinch roller that presses the recording paper to an end of the pinch roller,
2. A paper conveying apparatus for a printer according to claim 1, wherein said press contact adjusting means is adjusted in accordance with an output of said detector to correct a center position deviation of the recording paper. The pressure contact force adjusting means is an electromagnetic solenoid provided at an end of the pinch roller that applies an adjustment force in a direction opposite to the pressure contact direction of the pinch roller that presses the recording paper,
2. A paper conveying apparatus for a printer according to claim 1, wherein said press contact adjusting means is adjusted in accordance with an output of said detector to correct a center position deviation of the recording paper.

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