JPH07304194A - Thermal recording device - Google Patents

Abstract

PURPOSE:To obtain a thermal recording device with which printing is speeded up and resolution is heightened and high gradation can be easily obtained, by providing a light heat conversion member which is superposed on a thermosensible paper and heats when it receives laser beam from a laser scanning unit for projecting the laser beam. CONSTITUTION:When a part to be printed of a thermosensible paper P reaches in between a preheating drum 19 and a light heat conversion plate 15, paper feed rollers 16 and 17 are stopped once. When an LSU 12 projects laser beam to be controlled by an on-off system based on plotting information of characters to be printed, the laser beam reflects on a reflective mirror 13 and is projected on the light heat conversion plate to be superposed on the thermosensible paper P preheated by the preheating drum 19. Thus, the light heat conversion plate heats according to a pattern made by the plotting information of characters by the laser beam to be controlled by the on-off system. Accordingly, a part which comes into contact with the heating part of the light heat conversion plate is immediately colored, so that the pattern of the characters for one line is printed on the thermosensible paper P at a high speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-sensitive recording apparatus which prints characters and the like by heating a heat-sensitive paper and coloring the heat-generating portion thereof.

[0002]

2. Description of the Related Art As a thermal recording apparatus of this type, a recording head having a large number of heating elements arranged in a matrix is provided, and a predetermined one of the heating elements is selected by a character generating section. It is known that a desired character pattern is obtained by selectively heating and pressing the recording head in this state against a thermal paper that is colored by heat.

In recent years, the storability of heat-sensitive paper has been improved and the printing of color on the heat-sensitive paper has become possible, and the printing speed has been increased, the printing resolution has been increased, and the gradation expression of printing has been improved. Is required. Under such circumstances, according to the conventional thermal recording apparatus having the above structure, at least 1 ms is required to print one line, and the resolution is limited to 400 DPI. Further, when gradation is expressed in the conventional thermal recording apparatus, complicated thermal history control and the like are required in addition to pulse modulation control.

[0004]

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above-mentioned consciousness regarding the conventional thermal recording apparatus. It is possible to realize high speed printing and high resolution and easily obtain high gradation. An object is to provide a thermal recording device.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a thermal recording apparatus for printing a character or the like by heating the heat sensitive paper and coloring the heat generation portion thereof to print a character or the like. A laser scanning unit for irradiating a laser beam which is on / off controlled based on information; and a photothermal conversion member which is superposed on the thermal paper and generates heat when receiving the laser beam from the laser scanning unit.

[0006]

The present invention will be described below with reference to the illustrated embodiments.
FIG. 1 is a perspective view showing a main part of a first embodiment of a thermal recording apparatus according to the present invention. The thermal recording apparatus 11 does not have a recording head in which heat-generating elements are arranged in a matrix, which the conventional thermal recording apparatus has.

The heat-sensitive recording apparatus 11 includes a laser scanning unit (LSU) 12, a reflection mirror 13, a photothermal conversion plate (photothermal conversion member) 15, paper feed rollers 16 and 17 each composed of a pair of rollers, and an inner side. It has a hollow preheating drum 19 provided with a heating element 19a.

The LSU 12 is equipped with a laser light source (not shown), and irradiates a laser light whose on / off is controlled based on drawing information such as characters to be printed on the thermal paper P. Reflection mirror 13
Reflects the laser light from the LSU 12 and deflects the optical path toward the photothermal conversion plate 15. The photothermal conversion plate 15 is fixed to the main body of the apparatus and includes carbon black or the like that improves the efficiency of converting light into heat, and heats only the portion that receives the laser light to generate desired characters. A pattern based on drawing information can be formed. The photothermal conversion plate 15 is superposed on the thermal paper P, and the thermal paper P is colored by the pattern of characters or the like that has been heated to print.

The paper feed roller 16 holds the thermal paper P fed from a paper feed unit (not shown) and feeds it to the paper feed roller 17. The preheating drum 19, which is a platen roller, is located between the paper feed rollers 16 and 17, and faces the photothermal conversion plate 15. The preheating drum 19 arranged in this way is moved by the paper feed rollers 16 and 17 to the arrow A in FIG.
Contact with the back surface of the thermal paper P fed in the direction (paper feed direction). The preheating drum 19 is controlled to a temperature at which the thermal paper P does not develop color (a temperature below a coloring threshold) after the main power source (not shown) is turned on.

The present thermal recording apparatus 11 having the above structure
Operates as follows. That is, the main power source is turned on to oscillate the laser light source in the LSU 12 to heat the preheating drum 19 to a temperature below the coloring threshold. In this state, when the thermal paper P is sent out from the paper feed unit (not shown) in the paper feed direction, the paper feed roller 1 is synchronized with this.
6 and 17 start rotating and feed the sandwiched thermal paper P onto the preheating drum 19. Then, when the planned printing portion of the thermal paper P reaches between the preheating drum 19 and the photothermal conversion plate 15, the paper feed rollers 16 and 17 are temporarily stopped.

In this state, when the LSU 12 irradiates a laser beam whose on / off is controlled based on drawing information such as characters to be printed, the laser beam is reflected by the reflection mirror 13 and preheated by the preheating drum 19. Thermal paper P
The photothermal conversion plate 15 which is overlaid is irradiated. As a result, the photothermal conversion plate 15 generates heat according to the pattern of drawing information such as characters by the laser light that is controlled to be turned on and off. Therefore, the portion of the photothermal conversion plate 15 that comes into contact with the heat generating portion is immediately colored, so that the thermal paper P is
A pattern such as characters for a line is printed at high speed.

When the printing of one line is completed, the paper feed rollers 16 and 17 rotate in synchronization with this, until the next printing scheduled portion is positioned between the light-heat conversion plate 15 and the preheating drum 19. Send P in the paper feed direction. And
When the planned printing portion of the thermal paper P reaches the position, the paper feed rollers 16 and 17 are temporarily stopped and the same printing as described above is executed. When the printing speed is high, the paper feed rollers 16 and 17 are continuously fed without being temporarily stopped,
It is possible to print by irradiating laser light at a cycle that matches the resolution.

In this embodiment, as the light-heat converting member, the relatively hard light-heat converting plate 15 is used, but instead of this, a soft light-heat converting film having flexibility can be used.

Next, referring to FIG. 2, the second type of thermal recording apparatus is shown.
An example will be described. The second embodiment is different from the first embodiment in that the light-heat conversion plate 15 whose position is fixed is replaced with a flexible long-winding type light-heat conversion film 20, but the other parts are different. Are the same, the same reference numerals are given and the description thereof is omitted.

The light-heat conversion film 20 is a preheating drum 19
It is stretched between a pair of take-up rollers 21 and 22 arranged between the upper paper feed rollers 16 and 17. The take-up rollers 21 and 22 rotate in synchronization with the paper feed rollers 16 and 17, and the photothermal conversion film 20 can be taken up by a predetermined amount each time printing of one line is completed. Take-up rollers 21, 2
2 winds up the photothermal conversion film 20 while moving it from the winding roller 21 side toward the winding roller 22. Then, a predetermined amount of the photothermal conversion film 20 is provided on the winding roller 22 side.
When it is detected that the paper has been taken up, the take-up roller 21,
The rotation of 22 is switched in the opposite direction, and this time, the photothermal conversion film 20 is wound from the winding roller 22 side to the winding roller 21 side.

Therefore, according to the heat-sensitive recording apparatus 11 as described above, in addition to the same effect as the heat-sensitive recording apparatus 11 of the first embodiment, the heat-generating portion used for printing is not continuously used, whereby light-heat conversion is performed. The effect that the heat history control of the film 20 becomes extremely easy can be achieved.

Further, a third embodiment of the thermal recording apparatus will be described with reference to FIG. The third embodiment is different from the first embodiment in that the photothermal conversion plate 15 whose position is fixed is replaced with an endless photothermal conversion film 27, but the other parts are the same.

The thermal recording apparatus 11 of the third embodiment is L
A guide roller 23 surrounding the SU 12 and the reflection mirror 13,
It has 25 and 26. These guide rollers 23, 2
A long, endless photothermal conversion film 27 having flexibility is wound around 5 and 26. Guide roller 23,
25 and 26 rotate in synchronization with the paper feed rollers 16 and 17, and rotate the photothermal conversion film 27 in the arrow B direction (or arrow C direction) of FIG. As a result, the guide rollers 23, 25, 26 can move the portion that has been heated for printing, and position the portion having no heat history at the next printing scheduled portion.

Therefore, even with the thermal recording apparatus 11 as described above, the heat history of the photothermal conversion film 27 can be controlled very easily by not continuously using the heat generating portion used for printing, as in the second embodiment. It is possible to achieve the effect.

According to the above-described first to third embodiments, laser light is used as the energy source, and the condensed laser light is applied to the photothermal conversion plates (films) 15, 20, 27, and the photothermal conversion is performed. Plate (film) 15, 20, 27
Since the same pattern as the drawing information can be colored by the heat generated inside, if the scanning speed of the scanning system is improved, the printing speed can be easily increased accordingly, and the laser light If the light condensing property is improved, it is possible to easily realize higher resolution of printing accordingly. Furthermore, high gradation can be easily obtained by intensity modulation or pulse modulation of the laser light.

[0021]

As described above, according to the present invention, a laser scanning unit for irradiating a laser beam whose on / off is controlled based on drawing information such as a character to be printed on a thermal paper, and a laser scanning unit overlaid on the thermal paper, (EN) A thermal recording device that includes a photothermal conversion member that generates heat when receiving a laser beam from a scanning unit, realizes high-speed printing and high resolution, and can easily obtain high gradation. You can

[Brief description of drawings]

FIG. 1 is a perspective view showing an essential part of a first embodiment of a thermal recording apparatus according to the present invention.

FIG. 2 is a perspective view showing a main part of a second embodiment of the thermal recording apparatus.

FIG. 3 is a perspective view showing a main part of a third embodiment of the thermal recording apparatus.

[Explanation of symbols]

 11 Thermal Sensitive Recording Device 12 LSU (Laser Scanning Unit) 13 Reflection Mirror 15 Photothermal Conversion Plate (Photothermal Conversion Member) 16 17 Paper Feed Roller 19 Preheating Drum 19a Heating Element 20 27 Photothermal Conversion Film (Photothermal Conversion Member) 21 22 Winding Roller 23 25 26 Guide roller P Thermal paper

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B41J 3/20 116

Claims (6)

[Claims] 1. A thermal recording apparatus for heating a thermal paper and coloring the heat-generating portion to print a character or the like, wherein a laser beam is turned on / off based on drawing information of the character or the like to be printed on the thermal paper. A laser scanning unit; and a photothermal conversion member that is superposed on the thermal paper and generates heat when receiving laser light from the laser scanning unit;
A heat-sensitive recording apparatus comprising: 2. The heat-sensitive recording apparatus according to claim 1, wherein the light-heat conversion member is a light-heat conversion plate fixed to the apparatus main body. 3. The heat-sensitive recording apparatus according to claim 1, wherein the photothermal conversion member is made of a flexible material and is fixed to the apparatus main body. 4. The light-heat converting member according to claim 1, further comprising a pair of winding rollers, wherein the light-heat conversion member is made of a flexible and long material, and the pair of winding rollers forms one line. A thermal recording device that winds a specified amount each time printing is completed. 5. The heat-sensitive recording according to claim 1, wherein the light-heat conversion member is made of a flexible, long and endless material, and receives the laser light from the laser scanning unit on its inner peripheral surface to generate heat. apparatus. 6. The method according to any one of claims 1 to 5,
Further, the thermal recording apparatus has a preheating drum that heats the thermal paper before printing characters and the like.