JP5985864B2 - Printer and its paper guide mechanism - Google Patents

Description

  The present invention relates to a printer that conveys a print medium (hereinafter also referred to as “paper”) and performs printing. Furthermore, the present invention relates to a paper guide mechanism that guides paper conveyed in a printer.

  For example, in a label printer, a continuous label body in which labels of a predetermined length are temporarily attached at a predetermined interval on a long strip-like mount (separator) is used as paper. The paper is set in a paper holder in a state of being wound in a roll shape. A platen roller and a thermal head are provided in the paper transport path, and the paper is transported by rotating the platen roller in a state where the paper is pressed and held between the platen roller and the thermal head. When the thermal head performs heat scanning, printing is performed on the label surface of the paper.

  In general, in a printer, a paper guide mechanism is provided to guide a conveyed paper. In the paper guide mechanism, in order to cope with a plurality of types of paper having different widths, a guide member (pressing plate) that regulates the position of the paper is movable according to the width of the paper.

  For example, Patent Document 1 discloses a paper holder to which a paper roll can be easily attached. The paper roll is sandwiched between a pair of pressing plates and is rotatably supported. The pair of pressing plates are supported by a pair of moving members that are movably provided along the axial direction of the paper roll. When one of them is moved by the action of the pair of racks and a pinion, the other is moved with the same amount of movement. Also move. The pair of moving members are urged toward each other by the urging means, and the paper roll is held by the urging force of the urging means. In addition, when the stopper disposed between the pair of moving members moves in a direction in which the pair of moving members approach each other, the stopper contacts at least one of the moving members, and the distance between the pair of moving members is narrower than a certain value. Regulate not to fall.

  According to Patent Document 1, since the paper roll is clamped by the urging force of the urging means, even if a manual lock mechanism for manually locking a pair of pressing plates that guide the paper roll is not provided, The position in the axial direction can be restricted.

  Patent Document 2 discloses a roll paper support device that can easily set the distance between a pair of guide plates according to the width of the roll paper. This roll paper support device is provided in the axial direction of the roll paper supported by the support means, and is provided with a shaft means spanned between the left side frame and the right side frame, and movably guided by the shaft means. A left guide means and a right guide means for guiding the side surface of the roll paper supported by the support means, a biasing means for biasing the left guide means and the right guide means toward each other, a left guide means and a right guide means And a guide restricting means for restricting movement of the left guide means and the right guide means by the biasing force from the biasing means in a state where the guide means is set at a predetermined interval.

  According to Patent Document 2, the roll paper can be loaded on the support means in a state where the left guide means and the right guide means are set at a distance equal to or less than the maximum width roll paper by the guide restricting means. Also, by loading the roll paper on the support means, the restriction on the movement of the left guide means and the right guide means by the guide restriction means is released.

  In Patent Documents 1 and 2, a compression spring (coil spring) is used as the biasing means. However, since the length of the compression spring when the paper width is maximum is less than half that when the paper width is minimum, the biasing force of the compression spring when the paper width is maximum is More than twice the minimum. Thus, when the biasing force of the compression spring changes greatly with the length of the compression spring, particularly when the width of the sheet is large, the biasing force of the compression spring becomes a large load for transporting the sheet, and print shrinkage is caused. In some cases, this may cause a malfunction.

Japanese Patent Laid-Open No. 2002-3023 (Abstract, Claim 2, FIG. 2) JP 2008-222364 A (Claims 1 and 3, FIG. 1)

  Therefore, in view of the above points, the present invention does not change the urging force applied to the guide member so much even if the width of the paper is different, reduces the load of paper conveyance, and prevents problems such as print shrinkage. An object of the present invention is to provide a paper guide mechanism that can be used, and a printer including such a paper guide mechanism.

  In order to solve the above problems, a paper guide mechanism according to one aspect of the present invention is a paper guide mechanism that guides paper in a printer, and the positions in the width direction of the paper loaded in the printer casing are set on both sides. A pair of guide members that regulate from each other, a pair of spur gears, a pair of moving members that are arranged so as to be able to translate along a direction different from the paper transport direction, and respectively support the pair of guide members; A pair of spur gears are rotatably disposed at positions facing each other, a circular gear meshing with the pair of spur gears, at least one folding member attached to the housing, and a pair folded by the at least one folding member. A spring connected between one of the movable members and the housing, and biasing one of the pair of movable members toward the other by a contracting force. That.

  A printer according to one aspect of the present invention is a printer that conveys paper and performs printing, and includes a housing in which paper is loaded, a paper guide mechanism according to the present invention, and a housing. A platen roller that is driven and rotated by a driven motor to convey the paper, and a print head that performs printing on the paper with the paper sandwiched between the platen rollers.

  According to one aspect of the present invention, since the length of the spring can be made longer than before by folding the spring with at least one folding member attached to the housing, the width of the paper is different. The biasing force applied to the guide member does not change so much, and it is possible to reduce the load of paper conveyance and prevent problems such as printing shrinkage.

1 is a perspective view showing an overview of a printer equipped with a paper guide mechanism according to an embodiment of the present invention. FIG. 2 is a plan view showing a structure inside a housing of the printer shown in FIG. 1. It is a figure which shows the change of the length of a spring in case the width | variety of a paper differs.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same component and the overlapping description is abbreviate | omitted.
FIG. 1 is a perspective view showing an overview of a printer equipped with a paper guide mechanism according to an embodiment of the present invention. Hereinafter, a label printer in which a label continuous body in which labels of a predetermined length are temporarily attached on a long strip-like mount (separator) at regular intervals will be described as an example.

  As shown in FIG. 1, the label printer 1 is attached to a housing 2 in which a roll of paper wound in a roll shape is loaded, and to be openable and closable in the direction of the arrow in the figure. The front cover 3 and the top cover 4 are included. In the housing 2, a paper guide mechanism 10, a platen roller 21, at least one label sensor 22, and a control unit (not shown) are provided. An operation unit 23, a display unit 24, and a mount discharge port 25 are provided on the front surface of the housing 2, and a cover opening / closing lever for opening and closing the upper surface cover 4 on the side surface of the housing 2. 26 is provided.

  A peeling roller 31 for peeling the label from the mount is rotatably attached to the front cover 3. A recess 32 is formed in at least a portion of the front cover 3 to facilitate removal of the label. The top cover 4 is provided with a thermal head 41 and a transparent window 42 for confirming the state of the paper.

  The paper guide mechanism 10 guides paper in the label printer 1. The platen roller 21 is driven and rotated by a motor provided in the housing 2 to pull out and transport the paper from the roll paper loaded in the housing 2. The thermal head 41 performs printing on a sheet with the sheet sandwiched between the platen roller 21. The label sensor 22 detects the position of the label on the conveyed paper.

  The operation unit 23 includes a plurality of operation keys, and is used for operating the label printer 1 and inputting print data to the label printer 1. The display unit 24 includes a plurality of LEDs (light emitting diodes) and the like for displaying error messages and the like, and performs various displays based on signals supplied from the control unit. The control unit controls the conveyance of the sheet by the platen roller 21 and the printing of the sheet by the thermal head 41 based on the detection signal output from the label sensor 22.

  The printed paper comes into contact with the peeling roller 31. The mount is greatly bent by being folded downward in the figure. When the sheet is transported in this state, the label is peeled off from the mount when the sheet passes through the curved portion, and the transport of the sheet is temporarily stopped with a part of the label temporarily attached to the mount.

  As shown in FIG. 1, since a recess 32 is formed to facilitate removal of the label, inserting a finger into the recess 32 facilitates even a label with a short length in the transport direction. Can be removed. The mount after the label is peeled is discharged from the mount discharge port 25. In addition, you may provide the peeling sensor which detects whether the label was removed from the base_sheet | mounting_paper. In that case, when the peeled label is removed by the operator and the peel sensor no longer detects the label, the next label is printed and conveyed.

  FIG. 2 is a plan view showing the structure inside the housing of the printer shown in FIG. The housing 2 is formed with a paper storage recess 2a for storing the roll paper 5r around which the paper 5 is wound in a roll shape, and the paper guide mechanism 10 is installed in the paper storage recess 2a. . A platen roller holder 27 is attached to the housing 2. Two platen roller bearings 28 are held by the platen roller holding portion 27, and the platen roller 21 is rotatably held by these platen roller bearings 28.

  2, the paper guide mechanism 10 includes a pair of guide members 11a and 11b, a pair of moving members 13a and 13b each having a pair of racks (spur gears) 15a and 15b, a pinion gear (circular gear) 16, and A spring 17 as urging means and at least one folding member attached to the housing 2 for folding the spring 17 are included. The folding member may be a rotating member that is rotatably attached to the housing 2 or may be a fixed member that is fixed to the housing 2, but in the following, a pulley 18 that is rotatably attached to the housing 2. The case of using will be described.

  The position of the pair of guide members 11a and 11b is variable according to the width of the paper 5, and restricts the position in the width direction (axial direction of the roll paper 5r) perpendicular to the conveyance direction of the paper 5 from both sides. The pair of guide members 11a and 11b may be provided with bosses 12a and 12b on opposite surfaces, respectively. In that case, by inserting the bosses 12a and 12b into the cylindrical core of the roll paper 5r from both sides, the pair of guide members 11a and 11b hold the roll paper 5r from both sides and hold it rotatably. be able to.

  A pair of moving members 13a and 13b that support the guide members 11a and 11b, respectively, are provided below the pair of guide members 11a and 11b. Each moving member 13a or 13b may be manufactured integrally with the corresponding guide member 11a or 11b, or may be manufactured separately and coupled to the guide member 11a or 11b.

  Further, at least one paper upper surface guide 11c is integrally provided on at least one of the pair of moving members 13a and 13b. The paper upper surface guide 11c prevents the paper 5 from fluttering by pressing down the end in the width direction of the paper 5 drawn from the roll paper 5r, and the label sensor 22 (positioned at the opposite position across the paper 5). (See FIG. 1).

  The pair of moving members 13a and 13b are arranged to be able to move in parallel along a direction different from the conveyance direction of the sheet 5 (in FIG. 2, the width direction of the sheet 5). For example, the pair of moving members 13a and 13b are slidably fitted in a pair of guide grooves 14a and 14b formed on the bottom surface of the paper storage recess 2a, respectively. Thereby, a pair of guide members 11a and 11b can move in the direction which approaches or separates mutually, maintaining a parallel state.

  The pair of moving members 13a and 13b are provided with a pair of racks 15a and 15b each having teeth formed on a flat bar along the bottom surface of the sheet storage recess 2a. Each rack 15a or 15b may be manufactured integrally with the corresponding moving member 13a or 13b, or may be manufactured separately and coupled to the moving member 13a or 13b.

  The pinion gear 16 is rotatably disposed at a position where the pair of racks 15a and 15b face each other between the pair of moving members 13a and 13b, and meshes with the racks 15a and 15b. The racks 15a and 15b and the pinion gear 16 constitute a rack and pinion, and the linear motion of one rack 15a or 15b is converted into the rotational motion of the pinion gear 16, and the pinion The rotational movement of the gear 16 is converted into the linear movement of the other rack 15b or 15a. Accordingly, when one guide member 11a or 11b is moved by a desired distance in a desired direction, the other guide member 11b or 11a is also moved by the same distance in the opposite direction.

  The spring 17 is folded back by a pulley 18 and connected between one of the pair of moving members 13a and 13b and the housing 2, and one of the pair of moving members 13a and 13b is connected by contraction force. Energize towards the other. In FIG. 2, one end of the spring 17 is fixed to the moving member 13 a and the other end of the spring 17 is fixed to the bottom plate or the side plate of the housing 2. As a result, the roll paper 5r loaded in the paper storage recess 2a is urged from both sides by the pair of guide members 11a and 11b.

  A guide groove for guiding the spring 17 is formed in the pulley 18 along the circumference. The pulley 18 rotates following the spring 17 when the spring 17 expands and contracts, thereby defining a path through which the spring 17 passes and a function of changing the direction of the force (tension) applied to the spring 17. Have.

  FIG. 3 is a diagram illustrating changes in the length of the spring when the widths of the sheets are different. FIG. 3A shows a case where the paper width is maximum, and FIG. 3B shows a case where the paper width is minimum. In FIG. 3A, when the distance between the guide member 11a and the guide member 11b when the paper width is maximum is D, the length L1 of the spring 17 when the paper width is maximum is L1 = It is represented by a × D (a> 1). Here, in order to mitigate the change in the urging force of the spring 17 due to the change in the width of the paper, a ≧ 1.2, more preferably a ≧ 2. Therefore, the maximum value of the distance between the guide member 11a and the guide member 11b is Dmax, and the length L1 ′ of the spring 17 when the distance between the guide member 11a and the guide member 11b is the maximum is L1 ′. = A × Dmax (a ≧ 1.2, more preferably a ≧ 2).

  As shown in FIG. 3B, when the paper width is minimum, each of the guide members 11a and 11b moves inward by a distance ΔD compared to when the paper width is maximum. Thereby, the distance between the guide member 11a and the guide member 11b becomes (D-2ΔD). As described above, when L1 = a × D, the length L2 of the spring 17 when the paper width is minimum is L2 = (L1−ΔD) = (a × D−ΔD). In this state, the biasing force of the spring 17 is set so that the pair of guide members 11a and 11b bias the roll paper 5r (FIG. 2) loaded in the paper storage recess 2a with a minimum necessary force. .

  For example, in the conventional paper guide mechanism, assuming that L1≈D and ΔD≈D / 2, the spring length L2 when the paper width is minimum is the length of the spring when the paper width is maximum. It is about 50% of L1. Therefore, the biasing force of the spring when the paper width is maximum increases to about twice the biasing force of the spring when the paper width is minimum.

  On the other hand, in this embodiment, when L1 = 1.2 × D and ΔD≈D / 2, the length L2 of the spring 17 when the paper width is minimum is the maximum paper width. It is about 58% of the length L1 of the spring 17 at that time. Accordingly, the biasing force of the spring when the paper width is maximum is suppressed to about 1.7 times the biasing force of the spring when the paper width is minimum. Further, when L1 = 2 × D and ΔD≈D / 2, the length L2 of the spring 17 when the paper width is minimum is equal to the length L1 of the spring 17 when the paper width is maximum. It becomes about 75%. Therefore, the biasing force of the spring when the paper width is maximum is suppressed to about 1.3 times the biasing force of the spring when the paper width is minimum.

  In this way, by folding back the spring 17 using the pulley 18, the length of the spring 17 can be made longer than before, so that even if the width of the paper is different, it is applied to the pair of guide members 11 a and 11 b. The urging force does not change so much, and it is possible to reduce the paper conveyance load and prevent problems such as print shrinkage.

  In the present embodiment, since the spring 17 is folded back approximately 180 ° by the pulley 18, the length of the spring 17 can be increased to 1.2 times or twice or more of the conventional length. However, the present invention is not limited to this embodiment. For example, the folding angle of the spring 17 may be 90 ° to 180 °, or a plurality of folding members may be provided to further increase the length of the spring 17.

  DESCRIPTION OF SYMBOLS 1 ... Label printer, 2 ... Housing | casing, 2a ... Paper storage recessed part, 3 ... Front cover, 4 ... Top cover, 5 ... Paper, 5r ... Roll paper, 10 ... Paper guide mechanism, 11a, 11b ... Guide member, 11c ... Paper upper surface guide, 12a, 12b ... boss, 13a, 13b ... moving member, 14a, 14b ... guide groove, 15a, 15b ... rack, 16 ... pinion gear, 17 ... spring, 18 ... pulley, 21 ... platen roller, 22 ... Label sensor, 23 ... operation section, 24 ... display section, 25 ... mount discharge port, 26 ... cover opening / closing lever, 27 ... platen roller holding section, 28 ... platen roller bearing, 31 ... peeling roller, 32 ... recess, 41 ... thermal Head, 42 ... Window

Claims (3)

A paper guide mechanism for guiding paper in a printer,
A pair of guide members for regulating the position in the width direction of the paper loaded in the housing of the printer from both sides;
A pair of racks , each of which is disposed so as to be movable along a direction different from the conveyance direction of the paper, and a pair of moving members that respectively support the pair of guide members;
A circular gear pair of racks is rotatably disposed opposite to mesh with the pair of racks,
At least one folded member attached to the housing;
Which is connected between at least one folded by folding member and one of said pair of moving members and the housing, while urging said toward the other of the of the pair of moving members by the contraction force A spring having a length of at least 1.2 times the distance between the pair of guide members when the distance between the pair of guide members is the maximum ;
A pulley in which the at least one folding member is rotatably attached to the housing, and a guide groove for guiding the spring is formed along a circumference;
A paper guide mechanism comprising: Said spring, said at least one folded back substantially 180 ° by folding member, according to claim 1, wherein the sheet guide mechanism. A printer that conveys paper and prints,
A housing in which paper is loaded;
A paper guide mechanism according to any one of claims 1-2,
A platen roller that conveys paper by being driven and rotated by a motor provided in the housing;
A print head for printing on a sheet with the sheet sandwiched between the platen roller,
A printer comprising:

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