JP2008006674A - Thermal printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a thermal printer which can improve an accuracy of position of a thermal head to a platen roller. <P>SOLUTION: The thermal printer 11 is equipped with a body 13, a lid body 15, a hinge mechanism 16, a first positioning mechanism, and a second positioning mechanism. At the time of shifting a state from a second state P2 in which the lid body 15 is open to the body 13 to a first state P1 in which the lid body 15 hangs over the body 13, the first positioning mechanism positions a first platen roller 24 of the lid body 15 to a first thermal head 12 of the body 13, and also stations a second thermal head 14 of the lid body 15 near a second platen roller 22 of the body 13. The second positioning mechanism positions the second thermal head 14 stationed near the second platen roller 22 by the first positioning mechanism to the second platen roller 22 of the body 13. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a thermal printer capable of printing on both sides of a roll paper.

  For example, a double-sided printing mechanism that can simultaneously print on both sides of a thermal paper is known. The double-sided printing mechanism includes a first printing unit having a first thermal head and a first platen roller across a paper conveyance path, and a second thermal head and a second platen roller across the paper conveyance path. Are arranged symmetrically with each other.

  In this double-sided printing mechanism, first, the first thermal head prints on the surface of the thermal paper on the thermal paper passing through the paper conveyance path, and then the second thermal head prints on the back surface of the thermal paper. Thus, printing can be performed on both sides of the thermal paper (see, for example, Patent Document 1).

It is conceivable to apply the same configuration as the above-described double-sided printing mechanism to a thermal printer having an upper frame that can be opened and closed with respect to the main body. In this thermal printer, for example, the main body is configured to include only the first platen roller and the second thermal head. For example, a first thermal head and a second platen roller are disposed on the upper frame. Thus, when the thermal head and the platen roller are arranged on separate members, it is necessary to align the thermal head and the platen roller. For this reason, using the operation from the opened state to the closed state, the second thermal head of the lid is positioned on the second platen roller of the main body, and the first platen of the lid is positioned. A method of positioning the roller on the first thermal head of the main body can be used.
Japanese Patent Laid-Open No. 11-286147

  In the thermal printer having the above configuration, the thermal head and the platen corresponding to the thermal head are separately arranged in the upper frame and the main body. Had to be positioned. Therefore, it takes time and cost to manage the position accuracy, and the thermal printer as a whole has a problem that the manufacturing cost becomes high.

  An object of the present invention is to obtain a thermal printer that can improve the positional accuracy of a thermal head with respect to a platen roller with a simple configuration.

  In order to achieve the above object, a thermal printer according to one aspect of the present invention includes a main body having a first thermal head capable of printing on a first surface of roll paper, and the first surface of the roll paper. Is a lid having a second thermal head that can be printed on the second surface on the opposite side, a first state in which the lid is covered with the main body, and a second that is open with respect to the main body. A hinge mechanism that can be rotated between the first thermal head, a first platen roller that is provided on the lid so as to correspond to the first thermal head of the main body, and the first of the lid. A second platen roller provided on the main body so as to correspond to the second thermal head, and when the lid body transitions from the second state to the first state, the first of the lid body A platen roller is connected to the first therma of the main body. A first positioning mechanism that positions the second thermal head of the lid in the vicinity of the second platen roller of the main body, and the second positioning head by the first positioning mechanism. And a second positioning mechanism for positioning the second thermal head disposed in the vicinity of the platen roller with respect to the second platen roller of the main body.

  In another embodiment of the present invention, the lid is fixed to the hinge mechanism and supports the second thermal head, and the second frame supports the first platen roller. And a connecting portion for connecting the first frame and the second frame so that the second frame can be rotated with respect to the first frame.

  In this case, the first positioning mechanism includes a concave portion provided in the main body so that the first platen roller of the lid body is fitted in the first state, and the concave portion is fitted into the concave portion. The first platen roller is positioned with respect to the first thermal head, and through the positioning of the first platen roller, the second thermal head in the horizontal direction with respect to the second platen roller is positioned. The position is decided.

  The second positioning mechanism includes the first platen roller in a state of being fitted in the recess, the first frame, the second frame, and the connecting portion, and the recess. By rotating the first frame and the second frame so that the connecting portion is brought close to the main body with the first platen roller in a state of being fitted to the fulcrum as the fulcrum, the lid body The second thermal head is positioned on the second platen roller of the main body.

  The second positioning mechanism includes a hook member that is provided on the main body and engages with the lid body in the first state, and the hook member is configured to move the second platen roller with respect to the second platen roller. The vertical position of the thermal head is determined. In this case, it is preferable that the hook member is engaged in the vicinity of the connecting portion of the lid. The hook member may be engaged with the first frame of the lid. Further, the concave portion may have a semicircular shape with an open top.

  According to the present invention, since the second positioning mechanism is further provided in addition to the first positioning mechanism, the thermal head can be accurately positioned with respect to the platen roller with a simple configuration.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, the thermal printer 11 includes a main body 13 having a first thermal head 12, a lid body 15 having a second thermal head 14, and a hinge provided between the main body 13 and the lid body 15. And a mechanism 16. The hinge mechanism 16 can rotate the lid 15 between a first state P1 where the lid 15 covers the main body 13 and a second state P2 where the lid 15 is open with respect to the main body 13. I support it.

  As shown in FIGS. 1 and 2, the main body 13 includes a housing 21 that can accommodate the roll paper 17 therein, a first thermal head 12 that can print on the first surface 17 </ b> A of the roll paper 17, and a lid 15. A second platen roller 22 rotatably supported by the housing 21 so as to correspond to the second thermal head 14, a drive unit 23 that drives the feeding of the roll paper 17, and a driving force of the drive unit 23 Is transmitted to the first platen roller 24 and the second platen roller 22, the main body frame 26 supporting the hinge mechanism 16, and the first state P1 when the lid 15 is in the first state P1. A recess 27 into which the platen roller 24 is fitted, a hook member 28 that engages with the lid 15, and a part of the cutter mechanism 29 are provided.

  The roll paper 17 is made of double-sided thermal paper, for example. The roll paper 17 is held in a recess (not shown) inside the casing 21 so that it can rotate. For example, the second platen roller 22 is supported by the housing 21 so as to be rotatable with both ends. The drive unit 23 is configured by a stepping motor, for example. The recess 27 has a semicircular shape with the upper part opened. That is, the concave portion 27 has a complementary shape to the cylindrical first platen roller 24.

  For example, the hook member 28 can rotate around a shaft (not shown) provided at the lower end. The hook member 28 has, for example, a torsion coil spring hung between the housing 21. When a force is applied to the hook member 28 in a direction away from the second platen roller 22, the force acts on the hook member 28 in a direction approaching the second platen roller 22 due to the reaction of the torsion coil spring. It has become.

  The first thermal head 12 is disposed downstream of the second platen roller 22 in the feed direction of the roll paper 17. The first thermal head 12 is pressed toward the first platen roller 24 by a compression spring (not shown). The main body frame 26 has a long hole 26A through which the hinge mechanism 16 can slide in the horizontal direction.

  The lid 15 corresponds to the upper frame 33, the second thermal head 14 for printing on the second surface 17B opposite to the first surface 17A of the roll paper 17, and the first thermal head 12. As shown, the first platen roller 24 rotatably supported by the upper frame 33, a discharge port (not shown) for discharging the roll paper 17 to the outside, and the downstream of the first platen roller 24 are adjacent to each other. A part of the cutter mechanism 29 to be arranged. The first thermal head 12 is attached to the upper frame 33. The second platen roller 22 is supported by the upper frame 33 so as to be rotatable. The first thermal head 12 is disposed downstream of the second platen roller 22 in the feed direction of the roll paper 17.

  As shown in FIGS. 1 and 2, the upper frame 33 includes a first frame 34 fixed to the hinge mechanism 16, a second frame 35 separated from the first frame 34, and a first frame. The first frame 34 and the second frame 35 are hooked over a connecting portion 36 that connects the first frame 34 and the second frame 35 so that the second frame 35 can be rotated relative to the second frame 35. A torsion coil spring 37. A shaft portion 38 around which a torsion coil spring 37 is wound is provided on the connecting portion 36. The shaft portion 38 acts as the rotation center of the second frame 35. The first frame 34 includes a first pin 39 around which one end of a torsion coil spring 37 is wound, and an arm member 40 including an engagement pin 40A with which the hook member 28 is engaged. The engagement pin 40 </ b> A of the arm member 40 is disposed in the vicinity of the connecting portion 36.

  The second thermal head 14 is rotatably held by the first frame 34. The first platen roller 24 is rotatably held on the second frame 35 and a part of the cutter mechanism 29 is provided.

  The second frame 35 includes a second pin 44 around which the other end of the torsion coil spring 37 is wound, and a regulation pin 45 that regulates the rotation range of the second frame 35. The second frame 35 can rotate with respect to the first frame 34 around the shaft portion 38 of the connecting portion 36. The second frame 35 is pressed toward the main body 13 by the force of the torsion coil spring 37. In this state, the connecting portion 36 abuts against the regulation pin 45 so that the second frame 35 does not rotate further toward the main body 13.

  As shown in FIG. 2, the second thermal head 14 includes a head main body 48, a head frame 47 that supports the head main body 48 and can be rotated around a support shaft 46, and the head main body 48 is a second main body 13. And a compression spring 49 pressed against the platen roller 22.

  The printing operation of the thermal printer 11 will be briefly described with reference to FIG. In the thermal printer 11 of the present embodiment, first, the drive unit 23 is driven to rotate the reduction gear 25 to rotate the first platen roller 24 and the second platen roller 22. The roll paper 17 is fed toward the discharge port by the frictional force generated between the first platen roller 24 and the second platen roller 22 and the roll paper 17. Then, the second thermal head 14 performs a printing process on the second surface 17B of the roll paper 17. Subsequently, the first thermal head 12 performs a printing process on the first surface 17 </ b> A of the roll paper 17. Finally, the cutter mechanism 29 cuts the roll paper 17 into strip-like sheets, and the printing process of the thermal printer 11 is completed.

  As shown in FIG. 2, the thermal printer 11 positions the first platen roller 24 of the lid 15 with respect to the first thermal head 12 of the main body 13 and the second thermal head 14 of the lid 15. A first positioning mechanism 51 and a second positioning mechanism 52 for positioning with respect to the second platen roller 22 of the main body 13 are provided. The first positioning mechanism 51 includes the concave portion 27 of the main body 13 and the like. The second positioning mechanism 52 includes the first platen roller 24 fitted in the recess 27, the first frame 34, the second frame 35, the hook member 28, and the like. ing.

  Next, operations of the first positioning mechanism 51 and the second positioning mechanism 52 will be described with reference to FIGS.

  FIG. 2 shows a second state P <b> 2 in which the lid 15 is open with respect to the main body 13. As shown in FIG. 2, the upper frame 33 is in a state separated from the main body 13. In this state, the first frame 34 is pressed downward by a torsion coil spring 37. In this state, the connecting portion 36 of the first frame 34 contacts the restriction pin 45 of the second frame 35, and the rotation range of the second frame 35 is restricted.

  As shown in FIG. 3, when the user applies a closing operation to the lid body 15 so as to shift the lid body 15 from the second state P2 to the first state P1, the first platen roller 24 is moved to the first state. It fits into the recess 27 which is the positioning mechanism 51. With the first positioning mechanism 51, the first platen roller 24 can be positioned on the first thermal head 12. Further, when the first platen roller 24 is fitted into the recess 27, the second thermal head 14 is disposed in the vicinity of the second platen roller 22, and the second thermal head 14 is roughly positioned. In the state shown in FIG. 3, the engagement pin 40 </ b> A of the second frame 35 abuts against the flange portion 28 </ b> A of the hook member 28 and pushes the hook member 28 in a direction away from the second platen roller 22.

  As shown in FIG. 4, when the user continues to press the lid 15 further, the first frame 34 and the second frame 35 of the upper frame 33 are in a so-called reverse folded state. In the process of changing from the state of FIG. 3 to the reversely bent state of FIG. 4, the first platen roller 24 fitted in the recess 27 included in the second positioning mechanism 52 acts as a fulcrum. That is, since the second frame 35 can be rotated with respect to the first platen roller 24, the connecting portion 36 can be rotated so as to approach the main body 13 around the first platen roller 24. . Further, the first frame 34 also rotates simultaneously with the rotation of the second frame 35. By the rotation of the first frame 34 and the second frame 35, the connecting portion 36 is brought closer to the main body 13. When the connecting portion 36 approaches the main body 13, the engagement pin 40 </ b> A of the arm member 40 passes the flange portion 28 </ b> A of the hook member 28, and the hook member 28 moves so as to approach the second platen roller 22. In this case, a predetermined length of overlap L is generated between the engaging pin 40A of the arm member 40 and the lower end of the flange portion 28A of the hook member 28.

  The second thermal head 14 is pressed against the second platen roller 22. In the second thermal head 14, the head frame 47 rotates about the support shaft 46. The compression spring 49 is compressed by the rotation of the head frame 47, and the head main body 48 is pressed against the second platen roller 22 by the reaction of the compression spring 49.

  As shown in FIG. 5, when the user releases the pressing of the lid 15, the upper frame 33 recovers from the reverse folded state, and the first frame 34 and the second frame 35 are horizontal. Take. In this state, the hook member 28 as the second positioning mechanism 52 engages with the engagement pin 40 </ b> A of the arm member 40. Thereby, the vertical position of the second thermal head 14 is determined. In addition, when the upper frame 33 is in a horizontal state, the first platen roller 24 is maintained in a state where it is fitted in the concave portion 27 that is the first positioning mechanism 51. The horizontal position of the second thermal head 14 is determined by the concave portion 27 of the first positioning mechanism 51. Through such a process, the lid 15 is in the first state P1 covering the main body 13. As described above, the position of the first platen roller 24 and the position of the second thermal head 14 can be determined by the first positioning mechanism 51 and the second positioning mechanism 52.

  The above is the thermal printer 11 according to the embodiment. According to the present embodiment, since the second positioning mechanism 52 is further provided in addition to the first positioning mechanism 51, the positioning of the first thermal head 12 and the positioning of the second thermal head 14 are accurately performed. Can be done well. In particular, the second thermal head 14 is preliminarily disposed in the vicinity of the second platen roller 22 by the first positioning mechanism 51 and then positioned by the second positioning mechanism 52 on the second platen roller 22. Therefore, it is possible to position the second thermal head 14 and the second platen roller 22 at a long distance with higher accuracy than when the single positioning mechanism is used to position the second thermal head 14 and the second platen roller 22 at a time.

  The lid 15 includes a first frame 34 that supports the second thermal head 14, a second frame 35 that supports the first platen roller 24, and a second frame 35 relative to the first frame 34. A connecting portion 36 for connecting the first frame 34 and the second frame 35 so that the first frame 34 and the second frame 35 can be rotated. Thereby, it is possible to configure the split type upper frame 33 that can rotate the second frame 35 with respect to the first frame 34.

  The first positioning mechanism 51 includes a recess 27. The recess 27 positions the first platen roller 24 fitted in the recess 27 with respect to the first thermal head 12, and the first platen roller 24. Through this positioning, the horizontal position of the second thermal head 14 is determined with respect to the first platen roller 24. Thereby, the positioning of the first platen roller 24 and the positioning of the second thermal head 14 in the horizontal direction can be performed collectively.

  The second positioning mechanism 52 includes the first platen roller 24 fitted in the recess 27, the first frame 34, and the second frame 35, and is in a state of being fitted in the recess 27. The first thermal head 14 of the lid 15 is rotated by rotating the first frame 34 and the second frame 35 with the first platen roller 24 as a fulcrum so that the connecting portion 36 approaches the main body 13. Is positioned on the second platen roller 22 of the main body 13. As a result, the second thermal head 14 can be positioned with the first platen roller 24 fitted in the concave portion 27 of the main body 13 as a fulcrum, so that the second thermal head 14 can be positioned with higher accuracy. can do. In addition, since the second thermal head 14 is positioned by using the rotation of the first frame 34 and the second frame 35 with the first platen roller 24 fixed, the second thermal head 14 is positioned. The second thermal head 14 can be gradually brought closer to the second platen roller 22 of the main body 13. As a result, the second thermal head 14 is prevented from being abruptly abutted against the second platen roller 22 when positioning the second thermal head 14, and the impact caused when the second thermal head 14 hits the second platen roller 22 is prevented. Thus, it is possible to prevent a situation in which the second thermal head 14 is displaced.

  The second positioning mechanism 52 includes a hook member 28 provided on the main body 13 so as to be engaged with the lid body 15 in the first state P1, and the hook member 28 is second with respect to the second platen roller 22. The position of the thermal head 14 in the vertical direction is determined. For this reason, the second positioning mechanism 52 can determine the horizontal position and the vertical position of the second thermal head 14 in cooperation with the first positioning mechanism 51.

  The hook member 28 is adapted to engage with an arm member 40 located in the vicinity of the connecting portion 36 between the first frame 34 and the second frame 35. For this reason, the hook member 28 can be engaged with the connecting portion 36 having the largest movement amount, and the overlap L between the hook member 28 and the arm member 40 can be sufficiently taken. If the overlap L between the hook member 28 and the arm member 40 can be taken sufficiently, the engagement pin 40A will not come off without being engaged with the hook member 28, and the lid 15 can be securely attached to the main body 13. Can be fixed.

  The hook member 28 is engaged with the arm member 40 of the first frame 34 of the upper frame 33. Therefore, in the thermal printer 11 of the present embodiment, the first platen roller 24 of the first frame 34 is fixed by the concave portion 27 of the main body 13, and the second frame 35 is fixed by the hook member 28. become. For this reason, a fixing means for the main body 13 can be disposed on both the first frame 34 and the second frame 35, and the upper frame 33 can be stably held on the main body 13.

  The recess 27 has a semicircular shape with the upper part opened. For this reason, the first positioning mechanism 51 can be configured with a simple structure. Further, according to the semicircular recess 27, the horizontal position and the vertical position of the first platen roller 24 can be easily and accurately positioned. Furthermore, according to the semicircular recess 27, the horizontal position of the second thermal head 14 can also be accurately positioned.

  The thermal printer of the present invention is not limited to the one shown in the above embodiment. That is, in this embodiment, the roll paper is composed of double-sided thermal paper, but it may be printed on both sides of the roll paper using, for example, an ink ribbon. Of course, various modifications can be made without departing from the scope of the invention.

1 is a side view showing a thermal printer according to an embodiment. FIG. 2 is a cross-sectional view showing a state where an upper frame is raised in the thermal printer shown in FIG. 1. Sectional drawing which shows the state which the 1st platen roller of the upper frame shown by FIG. 2 has fitted in the recessed part which is a 1st positioning mechanism. FIG. 4 is a cross-sectional view showing a state in which the upper frame shown in FIG. 3 is folded back so as to bring the connecting portion closer to the main body. Sectional drawing which shows the state by which the upper frame shown by FIG. 4 was completely fixed to the main body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Thermal printer, 12 ... 1st thermal head, 13 ... Main body, 14 ... 2nd thermal head, 15 ... Cover body, 16 ... Hinge mechanism, 17 ... Roll paper, 17A ... 1st surface, 17B ... 1st 2 surface, 22 ... 2nd platen roller, 24 ... 1st platen roller, 27 ... recessed part 28 ... hook member, 34 ... 1st frame, 35 ... 2nd frame, 36 ... connection part, 51 ... 1st 1 positioning mechanism, 52 ... second positioning mechanism, P1 ... first state, P2 ... second state

Claims (8)

A main body having a first thermal head printable on the first side of the roll paper;
A lid having a second thermal head capable of printing on a second surface opposite to the first surface of the roll paper;
A hinge mechanism for holding the lid so as to be rotatable between a first state covering the main body and a second state open to the main body;
A first platen roller provided on the lid so as to correspond to the first thermal head of the main body;
A second platen roller provided on the main body so as to correspond to the second thermal head of the lid;
When the lid body transitions from the second state to the first state, the first platen roller of the lid body is positioned with respect to the first thermal head of the main body, and the lid A first positioning mechanism for disposing the second thermal head of the body in the vicinity of the second platen roller of the main body;
A second positioning mechanism for positioning the second thermal head disposed in the vicinity of the second platen roller by the first positioning mechanism with respect to the second platen roller of the main body;
A thermal printer comprising: The lid is
A first frame fixed to the hinge mechanism and supporting the second thermal head;
A second frame that supports the first platen roller;
A connecting part for connecting the first frame and the second frame so that the second frame can be rotated with respect to the first frame;
The thermal printer according to claim 1, further comprising: The first positioning mechanism includes a recess provided in the main body so that the first platen roller of the lid body fits in the first state,
The concave portion positions the first platen roller fitted thereto with respect to the first thermal head, and the positioning with respect to the second platen roller via the positioning of the first platen roller. The thermal printer according to claim 2, wherein the horizontal position of the second thermal head is determined.   The second positioning mechanism includes the first platen roller in a state of being fitted in the recess, the first frame, the second frame, and the connecting portion, and the recess. By rotating the first frame and the second frame so that the connecting portion is brought close to the main body with the first platen roller in a state of being fitted to the fulcrum as the fulcrum, the lid body 4. The thermal printer according to claim 3, wherein the second thermal head is positioned on the second platen roller of the main body. 5. The second positioning mechanism includes a hook member that is provided on the main body and engages with the lid in the first state;
The thermal printer according to claim 4, wherein the hook member determines a vertical position of the second thermal head with respect to the second platen roller.   The thermal printer according to claim 5, wherein the hook member is engaged in the vicinity of the connecting portion of the lid.   The thermal printer according to claim 6, wherein the hook member is engaged with the first frame of the lid.   The thermal printer according to claim 3, wherein the recess has a semicircular shape with an open top.

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