JP2004262018A - Thermal transfer printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal transfer printer which eliminates stretching balancing or wrinkle adjustment of an ink ribbon, and can prevent wrinkles because of strain brought about by biased printing or the like. <P>SOLUTION: A ribbon correcting part 20 comprising a plurality of projecting bodies 21 is set in a direction to intersect a surface of the ink ribbon at the downstream side of a printing part. The ribbon correcting part 20 consists of rotary bodies 22 having the plurality of projecting bodies 21 formed on the circumference, a shaft 24 penetrating the plurality of rotary bodies 22 and having both ends secured by E rings 23a and 23b, and a guide plate 25. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
FIELD OF THE INVENTION
The present invention relates to a thermal transfer printer that heats ink on an ink ribbon by a thermal head and transfers the ink to a sheet conveyed by a platen roller.
[0002]
[Prior art]
Conventionally, a thermal transfer printer that transfers the ink on the back side of the ink ribbon to the paper by holding the ink ribbon and the paper together by the thermal head and the platen roller that are arranged facing each other, and heating the thermal head as the paper is transported. Are known. The above-described thermal transfer printer passes the wound ink ribbon between the thermal head and the platen roller from the ribbon supply unit, and winds the ink ribbon together with the conveyance of the paper at the ribbon winding unit. The ink ribbon is evenly stretched by a plurality of guide members such as guide rollers and guide plates on the road so that skew and wrinkles of the ink ribbon are not corrected and generated.
In the above configuration, the guide member is provided with a tension adjustment mechanism for supporting and positioning and supporting the guide member so as to be displaceable in a direction intersecting with the surface of the ink ribbon. There is known a thermal printer which compensates for the difference in the amount of winding and prevents wrinkles of the ink ribbon caused by accumulation of the difference in the amount of winding. (For example, refer to Patent Document 1.)
[Patent Document 1]
JP-A-5-301355 (page 2-3, FIG. 1-3)
[0003]
In the tension adjusting mechanism of the above-mentioned patent document, a guide member is provided on the front surface of the bracket for supporting the thermal head (on the side of the winding portion of the ink ribbon), and a long hole is formed at each end of the guide member. The guide member is fixed by a screw that penetrates the long hole and fastens to the front surface of the bracket. Then, by loosening the screw and adjusting the inclination of the guide member by the long holes at both ends, the tension balance of the ink ribbon is adjusted so as to be displaceable, and the screw is fastened and fixed.
However, the above-mentioned tension adjusting mechanism adjusts the tension balance of the ink ribbon in a state where a screw is inserted through the long hole of the guide member and fastened to the front of the bracket, and adjustment by a skilled person such as customer service is reduced. Although possible, adjustments at the purchaser who purchases and uses the printer are very difficult.
Also, the surface of the ink ribbon that intersects with the guide member, which is the tension adjustment mechanism, is in contact with the surface or linearly, so that the inclination and shape errors of other guide members are adjusted in a state of being stretched uniformly, It is possible to compensate for the difference in the amount of winding, but if different print contents are biased in several places, or if there are print contents that are concentrated in one part such as black and white reverse printing, the thermal Since the heating from the head is also concentrated in a part, the ink ribbon is partially distorted. As a result, the ink ribbon is distorted due to the stretched portion (the portion where there is no print content) and the stretched portion (the portion where the ink ribbon is distorted). In addition, there is a problem that wrinkling of the ink ribbon caused by the collapse of the uniform stretching cannot be prevented.
Further, in order to solve the above problem with the tension adjusting mechanism, whenever the ink ribbon is inclined or wrinkled due to different printing contents, loosen the screw and adjust the inclination of the guide member with the long holes at both ends to adjust the screw. Since the fixing work is required, the adjustment work is troublesome, and even if the adjustment is performed, it is necessary to convey many ink ribbons until the entire ink ribbon is stretched evenly. There is a problem that it takes time to adjust.
[0004]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and provides a thermal transfer printer that does not need to adjust the tension balance and wrinkles of an ink ribbon and that can prevent wrinkles due to distortion caused by offset printing or the like. I do.
[0005]
[Means for Solving the Problems]
That is, the present invention focuses on dispersing the uneven balance and wrinkles of the ink ribbon by the stretching by point contact, and the thermal transfer printer according to claim 1 heats the thermal head. In a thermal transfer printer that transfers and prints ink on the back side of the ink ribbon to paper by printing, a ribbon straightening unit formed with a plurality of protrusions intersects the surface of the ink ribbon downstream of the thermal head in a ribbon transport path. And the stretching force is dispersed by point contact of the ink ribbon by the protrusion.
[0006]
The thermal transfer printer according to claim 2 holds the ink ribbon and the paper by a printing unit including a thermal head and a platen roller that are arranged to face each other, heats the thermal head, and applies the ink on the back surface of the ink ribbon to the paper. In the thermal transfer printer for transferring, the thermal transfer printer winds the ink ribbon transferred by the printing unit downstream from a ribbon supply unit that supplies the wound ink ribbon from upstream of the printing unit. A ribbon take-up section, and a guide member for guiding the transport of the ink ribbon, and a ribbon straightening section comprising a plurality of protrusions in a direction intersecting the surface of the ink ribbon downstream of the printing section. The ink ribbon is provided so as to be stretched by point contact with the surface of the ink ribbon.
[0007]
According to a third aspect of the present invention, in the thermal transfer printer, the ribbon straightening unit has a plurality of protrusions formed at substantially equal intervals on the circumference of the rotating body.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a preferred embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic explanatory diagram of a thermal transfer printer according to an embodiment of the present invention. The thermal transfer printer 1 includes a thermal head 11 fixed to a head bracket 10, a platen roller 12, a paper supply unit 13 for supplying the wound paper P in the direction of arrow A, and a wound ink ribbon R from upstream. A ribbon supply unit 14 for supplying the ink ribbon R in the direction of arrow B, a ribbon winding unit 15 for winding the ink ribbon R having the backside ink transferred to the paper P by heating the thermal head 11 downstream, and a process of transporting the ink ribbon R And tension rollers 16a and 16b for uniformly stretching the ink ribbon R.
Further, a ribbon straightening unit 20 for straightening and stretching wrinkles generated in the ink ribbon R is formed on the front surface of the head bracket 10 downstream of the transport of the ink ribbon R.
[0009]
FIG. 2 is a schematic perspective view for explaining a main part of the present invention.
The ribbon straightening unit 20 includes a rotating body 22 having a plurality of projecting bodies 21 formed on a circumference, a shaft 24 penetrating the plurality of rotating bodies 22 and having both ends fixed by E-rings 23a and 23b, and a guide plate 25. It is composed of
The guide plate 25 includes support portions 26a and 26b for supporting the shaft 24, a screw hole 27 for fixing, an elongated hole 28 for adjusting the mounting position of the guide plate 25 and adjusting the tension balance of the ink ribbon R, and It has an adjustment groove 29 and is fixed to the front surface of the head bracket 10 with screws 30a and 30b.
The rotating body 22 may be integrally formed, or may be formed in a unit length such as inches, so that the rotating body 22 is common to printers having plural head widths such as 4 inches and 5 inches. It can be used as a member.
[0010]
FIG. 3 is a schematic perspective view for explaining the operation of the main part of the present invention.
First, the wound ink ribbon R is transported from the ribbon supply unit 14 in the direction of arrow C, and different print contents are heated by the thermal head 11 and transferred to the paper P (not shown).
At this time, when printing is performed on a partly offset printing content such as a bar code or black-and-white reversal printing, the heating of the thermal head 11 is concentrated on a part of the ink ribbon R, so that distortion H occurs.
The distortion H is caused by the expansion and contraction of the base film of the ink ribbon R due to the heating of the thermal head 11, which causes the ink ribbon R to wrinkle.
The distortion H generated as described above is dispersed in the directions of a plurality of solid arrows in FIG. 3 by the protrusions 22 formed on the circumference of the rotating body 21 of the ribbon straightening unit 20, and the ink ribbon R is evenly stretched. Since the strain H generated by concentrating on a part is dispersed and stretched by the stretching force of the stronger point contact (the contact portion between the protruding portion 22 and the ink ribbon R), the heating of the thermal head 11 It is possible to prevent wrinkles due to distortion H generated when the base film of the ribbon R expands and contracts.
By setting the head width X of the thermal head 11 and the width Y of the ribbon correcting unit 20 to be X <Y, it is possible to flexibly respond to changes in the width direction of the paper P or the ink ribbon R to be used. .
Further, by the above operation, the ribbon straightening unit 20 only needs to adjust the tension balance at the time of manufacturing the printer or at the time of attaching and replacing the ribbon straightening unit 20, and evenly stretches the ink ribbon R and has a stronger strength. Since the one-sided tension is dispersed and stretched by the stretching force of the point contact, the wrinkles generated due to the inclination and the shape error of the conventional guide member can be prevented.
[0011]
In the present embodiment, the portion where the ribbon correction unit 20 abuts on the ink ribbon R is the rotating body 22 that is rotatable about the shaft 24. However, the present invention is not limited to this. The body 22 can be integrally formed and not rotated. However, in order to make the contact with the ink ribbon R smooth, it is desirable to use a rotatable rotating body.
Further, in the present embodiment, the ribbon straightening section 20 is fixed to the head bracket 10 with the screws 30a and 30b. However, since the adjustment due to the generation of wrinkles is not required, the ribbon straightening section 20 may be formed integrally with the head bracket 10. Further, a mechanism for independently supporting and fixing the ribbon straightening section 20 may be provided downstream of the front surface of the head bracket 10 in the middle of the ribbon transport path. However, in order to minimize wrinkles due to distortion H generated in the thermal head 11, it is more preferable to provide the thermal head 11 close to the thermal head 11.
[0012]
【The invention's effect】
As described above, according to the present invention, a ribbon straightening unit having a plurality of protrusions formed downstream of the ribbon transport path is provided, and a point contact point stronger than a force for uniformly stretching the ink ribbon by the protrusions of the ribbon straightening unit is provided. By stretching, it is possible to disperse the collapse of the tension balance due to the distortion of the ink ribbon, which is caused by the heating of the thermal head concentrated in a part, and it is unnecessary to adjust the tension balance and wrinkle of the ink ribbon. In addition, wrinkles due to distortion generated from offset printing or the like can be prevented.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory view of a thermal transfer printer according to an embodiment of the present invention.
FIG. 2 is a schematic perspective view for explaining a main part of the present invention.
FIG. 3 is a schematic perspective view for explaining the operation of the main part of the present invention.
[Explanation of symbols]
1 Thermal Transfer Printer P Paper R Ink Ribbon 10 Head Bracket 11 Thermal Head 12 Platen Roller 13 Paper Supply Unit 14 Ribbon Supply Unit 15 Ribbon Winding Unit 16a Tension Roller 16b Tension Roller 20 Ribbon Straightening Unit 21 Projecting Body 22 Rotating Body 23a E-ring 23b E-ring 24 shaft 25 guide plate 26a support portion 26b support portion 27 screw hole 28 long hole 29 adjustment groove 30a screw 30b screw H distortion

Claims (3)

In a thermal transfer printer that prints by transferring the ink on the back of the ink ribbon to paper by heating the thermal head,
A ribbon straightening unit formed with a plurality of protrusions is provided downstream of the thermal head on the ribbon transport path in a direction intersecting the surface of the ink ribbon, and the protrusions apply tension to the ink ribbon by point contact. A thermal transfer printer characterized by being dispersed. In a thermal transfer printer that sandwiches an ink ribbon and a sheet by a printing unit including a thermal head and a platen roller disposed opposite to each other, heats the thermal head, and transfers ink on the back side of the ink ribbon to the sheet,
The thermal transfer printer, a ribbon supply unit that supplies the wound ink ribbon from upstream of the printing unit,
A ribbon winding unit that winds the ink ribbon transferred by the printing unit downstream, and a guide member that guides conveyance of the ink ribbon,
A ribbon straightening unit comprising a plurality of protrusions is provided so as to be stretched by point contact with the surface of the ink ribbon in a direction intersecting with the surface of the ink ribbon downstream of the printing unit. Thermal transfer printer. 2. The thermal transfer printer according to claim 1, wherein the ribbon straightening unit has a plurality of protrusions formed at substantially equal intervals around a rotating body.

Images