JPS59190873A - thermal printer device - Google Patents

Abstract

PURPOSE:To simply exchange thermal heads by a method in which information representing the dispersion of resistance during the manufacturing period is added to thermal head side, and pulse width of reading-out is controlled by a drive pulse supplier through connectors during the connecting period. CONSTITUTION:A base plate-shaped connector 5 is formed of a pattern 6 permitting the mounting of a switch 8. After the assembling of a head portion 7 is complete, the resistance value of the head is measured, and according to the grade, the switch 8 is set up. On the other hand, the information input terminal of a micro processor 2 having a program preset is provided to the connector 4 so that optimum drive pulse width is generated by the grade information by the switch 8. When the heads are exchanged, the information of the switch 8 is read through the connector 4 by the micro processor 2 to generate drive pulse of optimum width, the dispersion of resistance is automatically corrected, and the density of printing is equalized.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a thermal printer device comprising a thermal head, means for supplying driving pulses to the thermal head, and a connector for connecting the two.・Yes.More specifically, it relates to a thermal printer device that automatically controls the pulse width of the drive pulse according to the resistance variation in the thermal head during manufacturing, making it possible to make the print density uniform. It is something.

[Background of the invention]

In general, thermal heads are manufactured using a process similar to the method of forming all thick film resistors or thin film resistors on a ceramic substrate, so the resistance value of the completed zero rad often varies widely. In order to reduce this variation, there is a method such as removing heads with particularly large variations through sorting, but in that case, the manufacturing yield decreases and the cost of the heads increases significantly. On the other hand, the operating principle of this head is
The resistor on the ceramic substrate manufactured in step 11 as described above.

A current is applied to generate resistance heat, and this heat is used to create thermal paper.

It is meant to produce color. Therefore, the intensity of color development is proportional to the amount of heat generated, that is, the applied power.゛When such a head is driven by a constant voltage source or a constant current source 2Ll, due to resistance variations that occur during the manufacturing of the head,
Print density changes.

There are methods to compensate for print density due to resistance variations in thermal heads, such as varying the head drive voltage to suit each individual head, and controlling the energization time, but these methods do not solve the problem. In either case, if the combination of drive device and head changes,
Measure the head resistance value at a specified temperature, for example 25°C, find the appropriate voltage or pulse width using a conversion table, etc., and drive to obtain it.

The disadvantage was that the device had to be readjusted.

This makes it especially impossible for ordinary customers to replace the head themselves if the head is damaged13.
Outside the manufacturer's service department.

The heads cannot be replaced, thus significantly increasing maintenance costs for thermal printing equipment.

The conventional head drive circuit is based on Fig. 1.

Explain. Here, 1 is 20 to drive the head.
- Control board, 2 is a microprocessor for controlling the pulse width of the drive pulse supplied to the thermal head, 6 is a drive circuit that drives the head, 4 is a connector that connects the control board and the head, 5 is a connector 4 and The mating board-type connector is a connecting wire 6 that connects the board-type connector and the head, and 7 is a head made by sintering a resistor on a ceramic substrate.

When the head 7 is energized to print, a microprocessor is programmed to set a pulse width suitable for the characteristics of the head 7 in advance.

2, the entire drive circuit 6 is passed through the part of the head that is desired to be colored black, and the rated voltage is applied. .

FIG. 2 shows a perspective view of this device.゛The lifespan of the head section is much longer than that of the printer itself due to wear or heat distortion caused by square wave drive.

Since the connector is short, we designed it to be easily removable in case it needs to be replaced, and we installed a connector as shown in Figure 2.

In many cases, connections are made using routes 4 and 5.

However, with this kind of circuit configuration, Hera 2 (°
4.

When the head was replaced, the head resistance and roughness caused longevity problems as mentioned above, and maintenance was extremely poor.

[Purpose of the invention]

The present invention was developed in order to solve the problems of the prior art as described above, and therefore, an object of the present invention is to reduce the print density even if the general customer replaces the damaged head by himself. It is an object of the present invention to provide a thermal printer device which does not change in temperature and has low maintenance costs.

[Summary of the invention]

The present invention uses several types of heads depending on their resistance values.

Divide into grades and micro-information on each grade.

13 on the head side as a means of transmitting information to Processera 1f.
Switch or Janno (-) on the board connector.

The class information is transmitted to the microprocessor via the connector via the wire, and the circuit is driven by that information.

Is there a program to change the width of the microphone in advance? ()
By inputting the information into the processor, we have realized a thermal printer device that automatically drives the head with a drive pulse of the optimum width just by replacing the head.

[Embodiments of the invention]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a block diagram showing one embodiment of the present invention.

Here, the numbers 1 to 7 trenches refer to the same ones as in Figure 1. 8 is a switch for setting the grade of heradopa (sometimes based on the Janno line).

The board type connector 5 is composed of a printed circuit board.

Therefore, it is possible to use it as a connector and at the same time pattern and mount a circuit. Take advantage of this fact when manufacturing board connectors.

Create a pattern to mount switch 8, and after assembling the head part, assemble the head.

Measure the resistance value, and set switch 8 according to its grade. On the other hand, the information input terminal of the microprocessor 2 into which the program has been input is added to the connector 4 in advance so that a drive pulse of the optimum width is generated using the 20 grade information from this switch.

By doing this, when the head is replaced, the microprocessor 2 reads the information from the switch 8 through the entire connector 4, and uses the information from the switch 8 to generate a drive pulse with a predetermined optimum width. It is possible to automatically correct resistance variations and maintain a constant print density no matter what grade of head is used.

An example of this specific mounting method is shown in a perspective view in FIG. Regarding Figure 4, there is no need to explain it again. 1' [Effects of the Invention] As described above, according to the present invention, there is provided a heat-sensitive pudding.

Even if the head is replaced for maintenance or other reasons, prints with the same density can be obtained without making one adjustment.

Since the head can be easily replaced even by a general user, maintenance costs can be significantly reduced.

In addition, in the manufacturing process, there is no need to manage the grade of heads or adjust combinations according to -rad, making it possible to significantly streamline the manufacturing process.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a conventional example of a head drive circuit, FIG. 2 is a perspective view thereof, FIG. 3 is a block diagram showing an embodiment of the present invention, and FIG. 4 is a perspective view thereof. Description of symbols 1...Control board 2...Microprocessor...Drive circuit 4...Connector 5...Board type connector 6...Connection line 7...Head
8...Switch banknote 1 diagram 〒4 diagram

Claims (1)

[Scope of Claims] It consists of a thermal head, a means for supplying driving pulses to the thermal head, and a connector for connecting the two, and the rad is connected to the thermal head by the pulses supplied from the driving pulse supplying means via the connector (7). In a thermal printer device that performs thermal recording by generating resistance heat, information indicating the degree of resistance variation that occurs during manufacturing is added to the thermal head side, and the drive pulse supply means is connected to the thermal head via a connector. A thermal printer device characterized in that, when connected to a thermal head, the information is read through the connector cover and the pulse width of a drive pulse supplied to the thermal head is controlled.1.