JP2011212994A - Thermal printer, and film winding guide roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal printer and film winding guide roller which can prevent the generation of wrinkle in both sides of an ink film.SOLUTION: The winding guide roller 27 is provided with the first shaft part 27a of drum shape, and the second and third shaft parts 27b, 27c of smaller drum shape formed in both sides of the first shaft part 27a. The first shaft part 27a contacts the center part of the ink film 11, and the second and third shaft parts 27b, 27c contact both sides of the ink film 11. If the ink film 11 is heated by a thermal head 21, the ink of the ink film 11 sublimates and forms an image on a transfer film 17. The used ink film 11 is guided by the winding guide roller 27. The winding guide roller 27 pulls the center part of the ink film 11 at the first shaft part 27a while pulling the side of the ink film 11 in the second and third shaft parts 27b, 27c. The ink film 11 is conveyed in the condition that there is neither slack in the center part nor wrinkle in the side part and wound by a winding core 13.

Description

  The present invention relates to a thermal printer and a film take-up guide roller for forming an image by heating an ink film.

  There are two types of thermal printers: a melting type that uses a melting type ink ribbon (ink film set) and a sublimation type that uses a sublimation type ink ribbon, both of which melt by heating the back of the ink film with a thermal head. Alternatively, the sublimated ink is transferred to a recording medium to form an image, characters, or the like. In this image formation, an ink film is pressed against a recording medium to form an image directly on the recording medium, and an ink film is superimposed on a transfer film to form an image once on the transfer film, and then the transfer film is applied to the recording medium. In some cases, the image is transferred onto a recording medium.

  In both of the case where an image is directly formed on a recording medium and the case where an image is formed on a transfer film, the ink film is conveyed to an image forming position by a conveying roller or the like, and then image formation is performed. At the time of image formation, a heating area that is narrower than the ink film and has the same shape as a recording medium (for example, a CD or a memory card) is heated. The ink film is heated by the thermal head, and the image is transferred to the recording medium or transfer film and the remaining ink layer becomes thin, so it extends in the film transport direction, but both sides that are not heated by the thermal head do not extend. Looseness occurs in the center. When slack occurs in the center, the ink film can be overlapped by a film take-up guide roller disposed downstream of the image forming position. Since this overlap becomes a wrinkle and extends to the image forming position, a print wrinkle that is a non-printed portion is generated.

  In the thermal transfer printer described in Patent Document 1, a film winding guide roller that guides the ink film is disposed between the thermal head and a winding core that winds up the ink film heated by the thermal head. The taking guide roller is formed in a drum shape in which the central portion in the width direction has a larger diameter than both ends. By pulling the central portion of the ink film with the drum-shaped film winding guide roller, the central portion of the ink film is prevented from being loosened.

JP-A-7-179933

  In the used ink film after image formation, the slackness in the center changes depending on the density of the image to be formed. In the sublimation type, when a dark color image such as a black image is formed, the heating time is longer than when a lighter color image such as a gray image is formed. . In Patent Document 1, since the central portion of the ink film is prevented by pulling the central portion of the ink film with a drum-shaped film winding guide roller, the central portion of the ink film when a black image is formed is prevented. The However, when a gray image is formed, the slack at the center is smaller than when a black image is formed, so the film winding guide roller pulls the center of the ink film too much, and conversely wrinkles are formed on both sides of the ink film. May occur.

  SUMMARY An advantage of some aspects of the invention is that it provides a thermal printer and a film take-up guide roller that can prevent wrinkles on both sides of an ink film.

  In order to achieve the above object, the film take-up guide roller of the present invention is a film take-up guide roller for guiding a used ink film toward the take-up core, wherein the center is the maximum shaft diameter and both sides are the minimum. A drum-shaped first shaft portion that gradually bulges from both sides toward the central portion so as to have a shaft diameter, and located on both sides of the first shaft portion, and the maximum shaft diameter and the minimum shaft diameter And a second shaft portion having a shaft diameter therebetween.

  Moreover, it is preferable that the center of the second and third shaft portions bulge out in a drum shape, or a spiral protrusion in the opposite direction is formed.

  The thermal printer of the present invention includes an ink film transport unit that transports an ink film drawn out from a supply core to a take-up core through an image forming position, and heats the back of the ink film at the image forming position. A thermal head that forms an image on a transfer film for transferring the image to the drum, and a drum-shaped drum that gradually bulges from both sides toward the center so that the center has the maximum shaft diameter and both sides have the minimum shaft diameter. First shaft portion, and second and third shaft portions located on both sides of the first shaft portion and having a shaft diameter between the maximum shaft diameter and the minimum shaft diameter. And a film take-up guide roller for guiding the ink film toward the take-up core.

  According to the present invention, the film central portion is pulled by the drum-shaped first shaft portion to prevent the film central portion from being slack, and the film is pulled by the second and third shaft portions on both sides of the first shaft. Since wrinkles on the side portions of the film due to excessive pulling of the portions are prevented, misprinting due to wrinkles can be prevented in the entire film width direction regardless of the image density.

It is a perspective view which shows a label printer. It is sectional drawing of the label printer which shows the state which forms the image in a transfer film. It is sectional drawing of the label printer which shows the state which rewinds the transfer film after formation of the image of 1 color. It is sectional drawing of the label printer which shows the state which has started transfer of the image to the disc. It is sectional drawing of the label printer which shows the middle of transferring the image to a disk. It is explanatory drawing which shows the conveyance path | route of an ink film. It is a figure which shows the winding state of the ink film to a winding guide roller. It is a block diagram which shows the electric constitution of a label printer. It is explanatory drawing which shows an ink ribbon. It is a table | surface which shows the printing result of this embodiment and a prior art example. It is a figure which shows embodiment which attached the coil to the winding guide roller.

  As shown in FIG. 1, the label printer 2 includes a disc tray 3 in which the disc D is loaded, and a main body case 4 in which a tray opening 4 a that allows the disc tray 3 to be taken in and out is formed. An opening / closing lid 5 is rotatably attached to the front surface of the main body case 4. The opening / closing lid 5 rotates around an axis 5a (see FIG. 2) between an open position for opening the tray opening 4a and a closed position (see FIG. 2) for closing the tray opening 4a. The opening / closing lid 5 is biased toward a closed position by a spring (not shown), and rotates in conjunction with the movement of the disc tray 3 by this spring.

  The disc tray 3 moves between a storage position (see FIG. 2) stored in the main body case 4 and a delivery position sent to the outside of the main body case 4 through the tray opening 4a. The disc tray 3 is formed with a recess 3a that matches the shape of the disc D, and the disc D is loaded into the recess 3a.

  As shown in FIGS. 2 to 5, an ink film set is detachably loaded in the main body case 4. The ink film set includes a cartridge, an ink ribbon 7 and a transfer ribbon 8 housed in the cartridge. 2 to 5, the cartridge is omitted and only the ink ribbon 7 and the transfer ribbon 8 are illustrated.

  The ink ribbon 7 includes, for example, a heat sublimation type ink film 11, a supply core 12, and a winding core 13. One end of the ink film 11 is attached to the supply core 12 and is wound around the supply core 12 in a roll shape. The other end of the ink film 11 is attached to the winding core 13.

  The transfer ribbon 8 includes a transparent transfer film 17 having substantially the same width as the ink film 11, a supply core 18, and a winding core 19. One end of the transfer film 17 is attached to the supply core 18 and is wound around the supply core 18 in a roll shape. The other end of the transfer film 17 is attached to the winding core 19.

  The main body case 4 houses a thermal head 21 and a platen roller 22 disposed at the image forming position, and a transfer roller 23 disposed at the image transfer position. A plurality of heating elements (not shown) are arranged in a line on the surface of the thermal head 21. The thermal head 21 presses the ink film 11 and heats it by a heating element to sublimate ink, and forms a press position (see FIG. 2) on the transfer film 17 and a retreat position away from the ink film 11 (FIG. 3). It is provided so as to be freely movable between. When the thermal head 21 forms an image on the transfer film 17, the platen roller 22 supports the transfer film 17 together with the pinch roller 29 and feeds or rewinds the transfer film 17.

  The transfer roller 23 is provided movably between a pressing position (see FIG. 5) for transferring the image by pressing the transfer film 17 against the disk D and a retracted position (see FIG. 2) away from the transfer film 17. ing.

  The main body case 4 includes a plurality of supply guide rollers 26 for guiding the ink film 11 supplied from the supply core 12 and a winding guide roller 27 for guiding the used ink film 11 after ink sublimation to the winding core 13. It is arranged. The main body case 4 is provided with a plurality of guide rollers 28 for guiding the transfer film 17.

  As shown in FIGS. 6 and 7, the winding guide roller 27 includes a drum-shaped first shaft portion 27a having a shaft diameter D1 at the center and a shaft diameter D2 (D2 <D1) on both sides, Taiko-shaped second and third shaft portions 27b and 27c are provided on both sides of the first shaft portion 27a and have a shaft diameter D3 at the center in the width direction. Under the condition that the shaft width W1 of the first shaft portion 27a and the shaft width W2 of the second and third shaft portions 27b and 27c are W2 <W1, the shaft diameter D3 is D2 <D3 ≦ D1. The first shaft portion 27 a contacts the central portion of the ink film 11, and the second and third shaft portions 27 b and 27 c contact both sides of the ink film 11.

  Fourth shaft portions 27d are provided on both sides of the second and third shaft portions 27b and 27c, respectively. The shaft diameter D4 of the fourth shaft portion 27d is, for example, the same as D2. Attachment shafts 27e are provided on both sides of the fourth shaft portion 27d, and are rotatably attached to the cartridge. 6 and 7, the central portions of the first shaft portion 27a, the second and third shaft portions 27b, 27c are exaggerated and protruded, and in FIG. 7, the thickness of the ink film 11 is exaggerated. ing.

  As shown in FIG. 8, the label printer 2 includes a control unit 31, an ink film winding mechanism 32, a transfer film winding mechanism 33, and a tray moving mechanism 34.

  The ink film winding mechanism 32 rotates the supply core 12 and the winding core 13 to transport and wind the ink film 11. The transfer film winding mechanism 33 rotates the platen roller 22, the supply core 18, and the winding core 19 to convey and wind the transfer film 17.

  The control unit 31 drives the thermal head 21 and the transfer roller 23 based on image data from a personal computer (not shown), and drives the ink film winding mechanism 32 and the transfer film winding mechanism 33.

  The tray moving mechanism 34 is driven by the control unit 31 and moves the disc tray 3. On the front surface of the main body case 4, a tray load / eject button 38 for loading and unloading (loading / ejecting) the disc tray 3 and a print button 39 for starting printing are provided. Note that loading / ejecting control and print start control of the disc tray 3 may be performed by connecting a personal computer (not shown) to the label printer 2 and by commands from this personal computer.

  As shown in FIG. 9, the supply core 12 includes a winding part 12a, a shaft part 12b, and a flange part 12c. The ink film 11 is wound around the winding portion 12a. The shaft portion 12b is rotatably attached to the cartridge.

  The winding core 13 includes a winding part 13a and a shaft part 13b. The winding unit 13 a winds up the ink film 11 sent from the supply core 12. The shaft portion 13b is rotatably attached to the cartridge. The supply core 18 and the winding core 19 of the transfer ribbon 8 have substantially the same shape as the supply core 12 and the winding core 13 and are rotatably attached to the cartridge.

  In the heat sublimation type ink film 11, different color inks are applied to a base film 41 wider than the disk D. In this embodiment, a black ink area 41a, a cyan ink area 41b, a magenta ink area 41c, and a yellow ink area 41d are formed in this order. When an image is formed on the transfer film 17, a heating area 41e having the same shape as the disk D is heated in each ink area 41a to 41d according to the recording density.

  Next, the operation of the above embodiment will be described. When recording an image on the disc D, first, the label printer 2 is turned on, and then the tray load / eject button 38 is operated. When the tray load / eject button 38 is operated, as shown in FIG. 1, the disc tray 3 moves to the delivery position, and the open / close lid 5 is pushed by the disc tray 3 and rotates to the open position.

  When the tray load / eject button 38 is operated after loading the disk D in the disk tray 3, as shown in FIG. 2, the disk tray 3 is moved to the storage position and the opening / closing lid 5 is rotated to the closed position by the spring. . Next, when the print button 39 is operated, the control unit 31 moves the thermal head 21 to the pressing position and presses the ink film 11 against the transfer film 17. In this state, the control unit 31 drives the ink film winding mechanism 32 to rotate the supply core 12 in the clockwise direction and send out the ink film 11. At the same time, the transfer film take-up mechanism 33 is driven, and the supply core 18 is rotated counterclockwise to send out the transfer film 17 on the ink film 11.

  Markers (not shown) for detecting the position of the ink film 11 are formed between the ink regions 41 a to 41 d of the ink film 11. When detecting that the black ink region 41a has reached the image forming position facing the thermal head 21 by detecting the marker between the ink regions 41a to 41d, the control unit 31 determines whether the black ink region 41a has reached the image forming position facing the thermal head 21. A plurality of heating elements arranged in a line of the thermal head 21 are energized in accordance with the pixel density. The heating element 41 e in the black ink area 41 a is heated by the heat generating element, the black ink is sublimated, and a halftone black image is formed on the transfer film 17. Thus, a black image is formed on the transfer film 17 line by line. Further, the thermal head 21 heats a part of the black ink region 41 a outside the heating region 41 e to form a band-shaped marker on the transfer film 17. At this time, the winding guide roller 27 pulls the central portion of the ink film 11 with the first shaft portion 27a and pulls both sides of the ink film 11 with the second and third shaft portions 27b and 27c. It is possible to suppress the occurrence of slack in the central portion and wrinkles on the side portions of the ink film 11 between the rollers 27.

  The ink film 11 on which the black image is formed is guided to the winding position by the winding guide roller 27 and is wound on the winding core 13.

  When the black image is formed on the transfer film 17, as shown in FIG. 3, the control unit 31 moves the thermal head 21 to the retracted position, and then drives the transfer film winding mechanism 33, so that the platen roller 22 The transfer film 17 is rewound and the supply core 18 is rotated clockwise to wind up the transfer film 17. Next, the control unit 31 sends out the ink film 11 and the transfer film 17 in a state where the portion of the transfer film 17 where the black image is formed is superimposed on the cyan ink region 41 b of the ink film 11. Similarly to the formation of the black image, a halftone cyan image is formed on the transfer film 17 so as to be superimposed on the black image by the cyan ink region 41b. Similarly, a black image, a cyan image, a magenta image, and a yellow image are sequentially formed on the transfer film 17 by performing ink transfer to the magenta ink region 41c and the yellow ink region 41d, thereby forming a full color image. Is done. As described above, the used ink film 11 is guided by the winding guide roller 27 and wound around the winding core 13.

  When the full-color image is formed on the transfer film 17, the control unit 31 moves the thermal head 21 to the retracted position and stops the ink film winding mechanism 32.

  The marker formed on the transfer film 17 is detected by a second marker detection sensor (not shown). Based on the detection result, the control unit 31 drives the ink film winding mechanism 32 and the transfer film winding mechanism 33 to align the ink regions 41 a to 41 d with the transfer film 17.

  As shown in FIG. 4, when the portion where the full color image is formed on the transfer film 17 arrives at the image transfer position facing the transfer roller 23, the control unit 31 moves the heated transfer roller 23 to the pressing position. The transfer film 17 is pressed against the disk D. The controller 31 aligns the image of the transfer film 17 and the disk D based on the detection result by a third marker detection sensor (not shown) provided in the vicinity of the transfer roller 23.

  As shown in FIG. 5, in the control unit 31, the winding speed of the transfer film 17 and the moving speed of the disk D (the moving speed from the storage position of the disk tray 3 toward the delivery position) are the same speed. Thus, the transfer film winding mechanism 33 and the tray moving mechanism 34 are driven. The image on the transfer film 17 is transferred to the moving disk D by heating and pressing by the transfer roller 23, and a full color image is recorded on the disk D. When the disc tray 3 moves to the delivery position (see FIG. 1), the disc D can be taken out.

  In order to confirm the effect of the present invention, when using the three types of film winding guide rollers of “present invention”, “comparative example 1”, and “comparative example 2”, respectively, The occurrence frequency of misprints (print wrinkles) on each roller was examined. Since the amount of elongation of the ink film 11 depends on the thickness of the remaining ink layer, misprinting also varies depending on the amount of transferred ink. Therefore, a sublimation ink film having a width of 130 mm using three types of inks of a cyan ink region, a magenta ink region, and a yellow ink region is used, and a black image (high density image) having a large transfer amount of the three types of ink, and an ink The case where a gray image (medium density image) with almost half the transfer amount was formed on a transfer film was examined. In consideration of the effects of instrumental differences in label printers, experiments were conducted on three label printers.

  FIG. 10 is a table showing the results of the experiment. In this table, “present invention” is the film winding guide roller shown in FIGS. 6 and 7, and “Comparative Example 1” and “Comparative Example 2” are conventional examples. The film winding guide roller of the present invention has D1 of 10 mm, D2 of 8 mm, and D3 of 9 mm. The length of the first shaft portion 27a is 101.6 mm, the length of the second and third shaft portions 27b and 27c is 6.2 mm, and the length of the fourth shaft portion 27d is 13.2 mm. “Comparative example 1” is a parallel guide roller having a shaft diameter of 8 mm over its entire length. “Comparative example 2” is a drum-shaped one, and in the film winding guide roller of the “present invention”, the second and third shaft portions are eliminated, and the shaft diameter of that portion is 8 mm.

  In the case of Comparative Example 1, in the gray image formation, the film heating time by the thermal head 21 was short, and the slack at the center of the film was small. However, in black image formation, since the film heating time is long and the slack in the center of the film is large, the three label printers had 32, 25, and 36 misprints, respectively.

  In the case of the comparative example 2, in the black image formation in which the central portion of the film has a large slack, since it has a drum shape, the central portion of the ink film 11 is pulled and the central portion of the film disappears. None of them had misprints. However, in the gray image formation in which the slack of the central portion of the film is small, the central portion that bulges in a drum shape pulls the central portion of the ink film 11 too much. For this reason, wrinkles occurred on the side of the ink film 11, and there were 13, 16 and 11 misprints with the three label printers, respectively.

  In the case of the present invention, in black image formation, the central portion of the ink film 11 is pulled by the first shaft portion 27a, thereby preventing the central portion of the film from being loosened. Further, in gray image formation, wrinkles on the side portions of the film, which are caused by excessively pulling the central portion of the film with the first shaft portion 27a, are prevented by pulling both sides of the ink film 11 with the second and third shaft portions 27b and 27c. Is done. As a result, there was no misprint in either the black image formation or the gray image formation.

  In the above embodiment, the second and third shaft portions are formed in a drum shape. However, for example, a step shape or an inclined shape may be used. In any of the shapes, it is preferable that the corners are rounded and the portion in contact with the ink film is a curve.

  FIG. 11 shows a winding guide roller in which a spiral protrusion is formed. In this embodiment, the coil 51 is used as the spiral protrusion. The winding guide roller 52 includes a drum-shaped first shaft portion 52a having a thicker central portion in the width direction than both sides, and second and third shaft portions 52b provided on both sides of the first shaft portion 52a. , 52c and mounting shafts 52d provided on both sides of the second and third shaft portions 52b, 52c. A coil 51a is attached to the second shaft portion 52b, and a coil 51b is attached to the third shaft portion 52c. The coil 51a and the coil 51b have opposite winding directions (inclinations) and are spirals that spread the ink film 11 outward when the winding guide roller 52 rotates. In addition, you may use the coil wound by the drum shape which the center expanded. That is, any member having a spiral shape such as a coil is applicable to the present invention. Further, instead of the coil, a coil-shaped convex portion (which may be spiral) may be integrally formed on the winding guide roller.

  Furthermore, in the above embodiment, a printer using a color ink film has been described. However, the present invention can also be used for a thermal printer using an ink film dedicated to a single color (for example, black only).

  Moreover, although the said embodiment demonstrated the thermal printer using a sublimation type ink film, this invention can be utilized also for the thermal printer using a melting type ink film.

  Furthermore, in the above embodiment, a printer is described that forms an image from an ink film onto a transfer film and transfers the image from the transfer film to a recording medium. However, the ink film is pressed against the recording medium, and the image is directly applied to the recording medium. The present invention can also be used for a thermal printer to be formed.

  In the above-described embodiment, a thermal printer that records an image on a disk is described. As a medium, a card-type medium, a deformed medium such as a star shape or a heart shape, a three-dimensional medium having a flat print surface, It may be paper or the like.

2 Label printer 11 Ink film 17 Transfer film 21 Thermal head 22 Transfer roller 27 Take-up guide roller 27a First shaft portion 27b Second shaft portion 27c Third shaft portion

Claims (6)

A film winding guide roller for guiding a used ink film toward a winding core,
A drum-shaped first shaft portion that gradually bulges from both sides toward the central portion so that the center is the maximum shaft diameter and both sides are the minimum shaft diameter;
Second and third shaft portions located on both sides of the first shaft portion and having a shaft diameter between the maximum shaft diameter and the minimum shaft diameter;
A film take-up guide roller comprising:   2. The film winding guide roller according to claim 1, wherein the second and third shaft portions bulge in the center in a drum shape.   The film winding guide roller according to claim 1, wherein the second and third shaft portions are formed with reverse spiral protrusions. An ink film conveying means for conveying the ink film drawn from the supply core to the winding core through the image forming position;
A thermal head that heats the back of the ink film at the image forming position and forms an image on a recording medium or a transfer film for transferring an image to the recording medium;
The drum-shaped first shaft portion that gradually bulges from the both sides toward the central portion so that the center is the maximum shaft diameter and both sides are the minimum shaft diameter, and located on both sides of the first shaft portion, A film winding guide roller having second and third shaft portions having a shaft diameter between a maximum shaft diameter and the minimum shaft diameter, and guiding a used ink film toward the winding core;
A thermal printer comprising:   5. The thermal printer according to claim 4, wherein the center of each of the second and third shaft portions bulges out in a drum shape.   The thermal printer according to claim 4, wherein the second and third shaft portions are formed with reverse spiral protrusions.

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