JPH07329321A - Thermal transfer printer - Google Patents

Abstract

PURPOSE:To prevent the movement and the jam of an ink ribbon at the time of executing a ribbon save in a thermal transfer printer having a ribbon save function for conveying only a print sheet without conveying the ribbon. CONSTITUTION:A tension motor 35 for operating a back tension at a ribbon supply roller is provided. A take-up drive motor 33 for rotatably driving a ribbon take-up roller is provided. A sheet conveying mechanism 5 for sequentially conveying print sheets to a thermal head 17 via an ink ribbon is provided. Ribbon save means for driving the motor 35 and the mechanism 5 without driving the head 17 and the motor 33 is provided. The back tension is operated at the ribbon by the motor 35 even at the time of executing the ribbon save.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer printer for transferring an ink of an ink ribbon to a printing paper by a thermal head to print an image.

[0002]

2. Description of the Related Art Generally, a thermal transfer printer such as a label printer is equipped with a thermal head in which heating elements are continuously arranged in the main scanning direction, and a pre-wound ink ribbon faces a heating element of the thermal head. A ribbon transport mechanism that is inserted into a position where the ribbon is wound and sequentially winds is formed by a ribbon winding roller and a drive motor. More specifically, in such a ribbon transport mechanism, a tension motor is connected to a ribbon supply roller that rotatably supports a pre-wound ink ribbon, and a ribbon take-up roller that sequentially takes up the ink ribbon is taken up. As a structure in which a drive motor is connected, a structure is known in which a tension motor or a winding drive motor conveys an ink ribbon while applying an appropriate tension to the ink ribbon.

Further, in the thermal transfer printer as described above, the printing paper which is in contact with the heating element of the thermal head via the ink ribbon is sequentially conveyed in the sub-scanning direction, and the ink of the ink ribbon is selectively applied to the printing paper by the thermal head. It is designed to be transferred to and printed with a dot matrix image.

In such a thermal transfer printer, if the ink ribbon is conveyed when the printing paper is conveyed without executing image printing, the ink ribbon is not used but is wound up, which is not preferable. In such a case, there is also a thermal transfer printer having a ribbon save function that conveys only the printing paper without conveying the ink ribbon by separating the thermal head from the platen. Therefore, in such a thermal transfer printer, a head pressing mechanism for pressing the thermal head to the platen via the ink ribbon and the printing paper is formed, and the thermal head is removed from the platen against the pressure of the head pressing mechanism. Some have a solenoid for separating them.

In such a thermal transfer printer, the thermal head is driven while the ink ribbon and the printing paper are conveyed while the head pressing mechanism is operating, and the solenoid presses the head pressing mechanism. In the released state, the printing paper is transported without transporting the ink ribbon.

[0006]

However, even when the ribbon save as described above is executed, when the conveyed printing paper comes into contact with the stopped ink ribbon, the ink ribbon moves and sags, or Jam may occur on the ink ribbon and print quality may deteriorate.

[0007]

A thermal head having heating elements facing a platen connected in the main scanning direction is provided, and a ribbon supply roller for axially supporting a pre-wound ink ribbon is provided on the ribbon supply roller. A tension motor that applies a back tension is provided, and a ribbon take-up roller that sequentially takes up the ink ribbon supplied from the supply roller and passed through the gap between the heating element of the thermal head and the platen is provided. A winding drive motor that rotationally drives the rollers is provided, a paper transport mechanism that sequentially transports printing paper in the sub-scanning direction is provided, and a separating mechanism that separates the thermal head from the platen is provided, and the thermal head and the tension motor are provided. And an image printing unit for driving the winding drive motor and the paper transport mechanism, The head and the winding drive motor provided with a ribbon saving means for driving the separating mechanism and the tension motor and the paper transporting mechanism without driving.

[0008]

When printing is performed on the printing paper, the tension motor is used to apply the tension while the winding drive motor conveys the ink ribbon, and the paper conveyance mechanism conveys the printing paper to drive the thermal head to perform the printing. To do. Further, when performing ribbon save, the ribbon save means drives the separating mechanism, the tension motor and the paper conveying mechanism without driving the thermal head and the winding drive motor, so that the tension is saved even when the ribbon save is executed. Back tension is applied to the ink ribbon by the motor.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. It should be noted that the directions such as front and rear and up and down in the present embodiment are defined for convenience in order to simplify the description, and this does not limit the actual installation or use direction of the device.

First, in the label printer 1 which is the thermal transfer printer exemplified in this embodiment, mechanically, as illustrated in FIG. 2, a large number of labels 3 can be peeled off on the surface of a mount 2 made of continuous paper. Label sheet 4 attached at regular intervals
Is set on the sheet conveying mechanism 5 which is a sheet conveying mechanism. The sheet conveying mechanism 5 includes the sheet feeding roller 6, the sheet guides 7 and 8, the guide roller 9, the pinch roller 10 and the platen here. It is composed of rollers 11.

Further, in this label printer 1, a label peeling member 12 for peeling the label 3 by bending the mount 2 of the label sheet 4 at a steep angle is provided in front of the platen roller 11. Further, a mount take-up mechanism 13 that winds up the mount 2 on which the label 3 of the label sheet 4 is peeled is provided below the label peeling member 12, and the mount take-up mechanism 13 is
Here, the mount guides 14 and 15 and the mount winding roller 16 are used.

Further, the thermal head 17 is pivotally supported at its rear end portion and is press-contacted to the platen roller 11 so as to be able to come into contact with and separate from the platen roller 11, and the label sheet 4 makes a gap between the thermal head 17 and the platen roller 11. It is supposed to pass. In the label printer 1, the ribbon supply roller 18, the ribbon take-up roller 19, the guide frame 20
This constitutes a ribbon transport mechanism 22 for sequentially transporting the ink ribbon 21 wound in a roll shape, and the ink ribbon 21 transported by the ribbon transport mechanism 22.
Is passed over the gap between the thermal head 17 and the platen roller 11 in a state of being overlapped with the label sheet 4, and is wound up by the ribbon winding roller 19.

A leaf spring member (not shown) as a head pressing mechanism presses the upper surface of the front end of the thermal head 17 downward, and the thermal head 17 is mediated by the ink ribbon 21 and the label sheet 4. Is pressed against the platen roller 11. Further, a separating mechanism (not shown) is provided for separating the thermal head 17 from the platen roller 11 within a range where the plate spring member is elastically deformed against the pressure of the plate spring member. This separating mechanism is formed by a solenoid 36, a link, etc. (not shown), and when the solenoid 36 is operated, the front end portion of the thermal head 17 connected via the link is lifted to lift it from the platen roller 11. It is a mechanism to separate.

Further, in this label printer 1, a transmissive photo sensor 23 for detecting the ink ribbon 21 is arranged behind the thermal head 17, and the guide roller 9 is arranged behind the thermal head 17. A photo sensor 24, which is a combination of a transmissive type and a reflective type for detecting the label sheet 4, is arranged in parallel in the front side.

Here, in the label printer 1, various kinds of data such as a control program are fixed to a CPU (Central Processing Unit) 25 that executes various kinds of data processing in a circuit manner, as illustrated in FIG. ROM (R
ead only memory) 26, RAM (Random Access Memory) 2 for temporarily storing various data such as print data in an updatable manner
7. I / F (Interface) 28 that receives various data such as print data from a host computer (not shown), reference clock 29 that constantly outputs clock pulses, the thermal head 17, the photosensors 23 and 24, the A pulse motor 30 that rotationally drives the sheet supply roller 6 and the platen roller 11 of the sheet transport mechanism 5, a pulse motor 31 that rotationally drives the mount take-up roller 16 of the mount take-up mechanism 13, and a rotating portion of the pulse motor 31. A photo sensor 32 of a rotary encoder (not shown) directly connected to the rotary shaft and a DC (Direc) which is a winding drive motor for rotationally driving the ribbon winding roller 19 of the ribbon transport mechanism 22.
t Current) motor 33, photosensor 34 of a rotary encoder (not shown) directly connected to a rotary shaft that is a rotating part of the DC motor 33, and tension for applying back tension to the ribbon supply roller 18 of the ribbon transport mechanism 22. A DC motor 35, which is a motor, and a solenoid 36, which is a drive source of the separating mechanism, are connected by a system bus 37.

Further, in the label printer 1, the thermal head 17, the pulse motor 30 of the sheet transport mechanism 5, the pulse motor 31 of the mount winding mechanism 13, the DC motors 33 and 35 of the ribbon transport mechanism 22 are used. Power supply means for supplying drive power is provided as a power supply circuit (not shown) connected to a commercial power supply.

In the label printer 1, the CPU 25 executes various data processing according to the data stored in the ROM 26 and the RAM 27, and the two DCs of the thermal head 17 and the ribbon transport mechanism 22 are processed.
Image printing means for driving the motors 33 and 35, the pulse motor 30 of the sheet conveying mechanism 5 and the pulse motor 31 of the mount winding mechanism 13 is provided. At this time, the solenoid 36 of the separating mechanism is not driven.

When executing the ribbon save, the R
The CPU 25 executes various data processes according to the data stored in the OM 26 and the RAM 27, and the DC for winding the thermal head 17 and the ribbon transport mechanism 22.
The solenoid 3 of the separating mechanism is not driven by the motor 33.
6, ribbon drive means for driving the DC motor 35 for tensioning the ribbon transport mechanism 22, the pulse motor 30 of the sheet transport mechanism 5, and the pulse motor 31 of the mount take-up mechanism 13 are provided.

In such a structure, in the label printer 1, when the image is printed on the label 3 of the label sheet 4, the image printing means includes the thermal head 17 and the ribbon transport mechanism as illustrated in FIG. 22 two DC
The motors 33 and 35 and the pulse motor 3 of the sheet conveying mechanism 5
0 and the pulse motor 31 of the mount winding mechanism 13 are driven.

By doing so, the sheet conveying mechanism 5
Conveyance of the label sheet 4 by the platen roller 11 of
A heating element (not shown) of the thermal head 17 is synchronized with the conveyance of the ink ribbon 21 by the ribbon conveyance mechanism 22.
Is selectively driven to generate heat according to the print data.
1 ink is selectively transferred to the label 3 to print an image of a dot matrix. The thermal head 17
The heating elements are arranged in a direction (main scanning direction) orthogonal to the conveyance direction (sub scanning direction) of the printing paper.

The label sheet 4 which has passed the position of the thermal head 17 is bent at a sharp angle by the label peeling member 12 to peel the label 3 from the mount 2, and the front half of the label 3 is projected to the outside. Stop in the state. Therefore, the label printer 1 that has detected that the label 3 has been taken out by the user restarts the printing operation as described above. Further, the mount 2 with the label 3 peeled off in this way
Since the mount paper take-up mechanism 13 sequentially winds the paper, the unnecessary mount paper is not discharged to the outside of the apparatus to clutter the surroundings.

In the label printer 1, when executing the ribbon save, the ribbon save means drives the thermal head 17 and the winding DC motor 33 of the ribbon transport mechanism 22, as illustrated in FIG. Without contact, the solenoid 36 of the separating mechanism, the DC motor 35 for tension of the ribbon transport mechanism 22, and the pulse motor 3 of the sheet transport mechanism 5
0 and the pulse motor 31 of the mount winding mechanism 13 are driven. By doing so, when the area where there is no data to be printed on the label sheet 4 is long, that is, when the area where the thermal head 17 is not driven is long, the label is saved without carrying the ink ribbon 21 by the ribbon save function. Since only the sheet 4 is conveyed, unnecessary consumption of the ink ribbon 21 can be prevented.

In the label printer 1, the ribbon transport mechanism 22 is used even when the ribbon save is executed as described above.
The DC motor 35 is driven with a very small voltage "V" (the drive torque of the DC motor 35 is a voltage at which the ink ribbon 21 is not conveyed in the direction opposite to that in the case of normal printing due to mechanical friction) and the back tension is set to ink. It is designed to act on the ribbon 21. Therefore, the conveyed label sheet 4 comes into contact with the stopped ink ribbon 21 and the ink ribbon 21 moves, and the ink ribbon 21 is loosened to cause wrinkles on the ink ribbon 21 at the time of printing to deteriorate print quality. In addition, a jam does not occur on the ink ribbon 21.

By appropriately changing the voltage of the DC motor 35 at the time of ribbon save in accordance with the winding diameter of the ink ribbon 21 on the ribbon supply roller 18, the power consumption can be reduced without moving the ink ribbon 21. Can be reduced.

[0025]

As described above, according to the present invention, the thermal head having the heating elements facing the platen connected in the main scanning direction is provided, and the ribbon supply roller for axially supporting the pre-wound ink ribbon is provided. A tension motor that applies a back tension to the ribbon supply roller is provided, and a ribbon winding roller that sequentially winds the ink ribbon supplied from the supply roller and passed through the gap between the heating element of the thermal head and the platen is provided. A winding drive motor that rotationally drives the ribbon winding roller is provided, a paper transport mechanism that sequentially transports printing paper in the sub-scanning direction is provided, and a separating mechanism that separates the thermal head from the platen is provided. And an image printing unit that drives the tension motor, the winding drive motor, and the paper transport mechanism, By providing the ribbon save means for driving the separating mechanism, the tension motor and the paper transport mechanism without driving the thermal head and the take-up drive motor, the ink ribbon is driven by the tension motor even when the ribbon save is executed. Since a back tension is applied to the thermal transfer printer, it is possible to provide a thermal transfer printer that does not cause slack due to the movement of the ink ribbon when the conveyed printing paper comes into contact with the stopped ink ribbon.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a circuit structure of a thermal transfer printer according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional side view illustrating an internal structure.

FIG. 3 is a drive relationship between a pulse motor of a sheet transport mechanism that is a paper transport mechanism, a pulse motor that is a winding drive motor, a pulse motor that is a tension motor, and a solenoid of a separation mechanism when executing image printing and ribbon save. 2 is a time chart illustrating the above.

[Explanation of symbols]

 1 Thermal Transfer Printer 5 Paper Conveying Mechanism 17 Thermal Head 18 Ribbon Supply Roller 19 Ribbon Winding Roller 21 Ink Ribbon 33 Winding Drive Motor 35 Tension Motor

Claims (1)

[Claims] 1. A thermal head in which heating elements facing a platen are connected in a main scanning direction, a ribbon supply roller for axially supporting a pre-wound ink ribbon, and a tension for applying a back tension to the ribbon supply roller. A motor, a ribbon winding roller that sequentially winds the ink ribbon supplied from the supply roller and passed through the gap between the heating element of the thermal head and the platen, and a winding drive that rotationally drives the ribbon winding roller. A motor, a paper transport mechanism that sequentially transports printing paper in the sub-scanning direction, a separating mechanism that separates the thermal head and the platen from each other, the thermal head, the tension motor, the winding drive motor, and the paper transport mechanism. Without driving the image printing means for driving and the thermal head and the winding drive motor. A thermal transfer printer comprising: the separating mechanism, the tension motor, and a ribbon save unit that drives the sheet conveying mechanism.