JPH09262995A - Thermal head, printer using the same, and printer system using the printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily detect foreign matters attached to a printing surface by interposing piezoelectric elements between a heat-resistant substrate and heating resistors. SOLUTION: A thermal head is equipped with a head main body 3 equipped with a heat-resistant substrate such as an alumna substrate and head heating elements 1 integrated on the heat-resistant substrate of the head main body 3 and containing heating resistors. Membrane like piezoelectric elements 2 are interposed between the head main body 3 and the head heating elements 1. The piezoelectric elements 2 are pressed by the attachment of foreign matters and the adhesion of foreign matters is detected by a change of output voltage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal head, a printer device using the thermal head, and a printer system using the printer device, and more particularly,
The present invention relates to a thermal head suitable for printing securities, cash vouchers, etc., a printer device using this thermal head, and a printer system using this printer device.

[0002]

2. Description of the Related Art Conventionally, thermal printers have been widely used for printing securities and vouchers. The basic structure of the thermal head is such that a heating resistor (a thin film of about 0.1 μm such as tantalum nitride or ruthenium oxide) and a wear-resistant layer (such as tantalum oxide) are integrated on a heat-resistant substrate such as an alumina substrate. The application of an image signal pulse of several milliseconds causes the heat generating resistor to generate heat by several hundred degrees, and thermal transfer recording is performed by combining an ink ribbon or a sheet and paper.

[0003]

However, in the above-mentioned prior art, if foreign matter such as dust adheres to the printing surface of the thermal head, printing defects such as missing prints occur and illegal securities or gold notes are issued. There was an inconvenience.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a thermal head, a printer device, and a printer system, which are capable of improving the disadvantages of the conventional example and, more particularly, capable of easily detecting the presence of foreign matter adhering to the printing surface. And

[0005]

In order to achieve the above object, the thermal head according to claim 1 is a thermal head in which a heat-generating resistor is integrated on a heat-resistant substrate such as an alumina substrate. The structure is such that a piezoelectric element is interposed between the body and the body.

According to the present invention, when dust adheres to the printing surface and the heating resistor is pressed by the close contact with the recording paper, the ink ribbon, etc., the pressing force acts on the piezoelectric element, and the terminals of the piezoelectric element are pressed. A predetermined voltage change is caused by the direct effect.
From this voltage change, it can be detected that dust is attached to the print surface.

According to another aspect of the printer device of the present invention, the thermal head according to the first aspect of the present invention, the detection unit for detecting the output voltage of the piezoelectric element, and the change in the output of the detection unit exceed a preset fixed amount. And a printer control unit for issuing a warning signal to the host device, and an output unit for notifying the host device of the warning signal issued from the printer control unit.

According to the present invention, when the voltage change of the piezoelectric element exceeds a preset fixed amount, the printer control unit determines that dust is attached to the print surface of the thermal head, and issues a warning signal. The issued warning signal is output to an upper-level device to notify the higher-level device, and the higher-level device recognizes the attachment of dust to the thermal head.

According to a third aspect of the present invention, there is provided a printer system including the printer device according to the second aspect and a host device for outputting print data to the printer device. The configuration is such that a receiving unit that receives a signal, a warning unit that issues a warning to the operator, and a control unit that receives the warning signal at the receiving unit and issues a warning to the warning unit are adopted.

In the present invention, when dust adheres to the print surface of the thermal head, the printer device outputs a warning signal. Upon receiving the warning signal, the host device controls the control unit to display the fact that dust adheres on the warning unit or to notify the operator by a warning sound.

Accordingly, the above-mentioned object is to be achieved.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIG.

FIG. 1 shows the structure of the thermal head. FIG.
, A thermal head comprises a head body 3 provided with a heat-resistant substrate such as an alumina substrate, and a head heating element 1 integrated on the heat-resistant substrate of the head body 3 and including a heating resistor.
And A thin-layer piezoelectric element 2 is interposed between the head body 3 and the head heating element 1.

More specifically, in the present embodiment, the head body 3 is formed by laminating a glass layer on the surface of an alumina substrate. On the other hand, the head heating element 1 is formed by sequentially laminating a heating resistor layer, an electrode pair for applying an image signal pulse, an antioxidant layer, and a wear-resistant layer on the glass layer via the piezoelectric element 2. . Further, the thin-layer piezoelectric element 2 is interposed between the above-mentioned glass layer and the heating resistor layer via an insulating layer in a state in which electrode layers for charge detection are sputtered or vapor-deposited on both surfaces.

FIG. 2 shows a block diagram of the printer system in this embodiment. In FIG. 2, a printer device 10 includes a thermal head 5 having the above-described piezoelectric element 2, a detecting unit 4 for detecting an output voltage of the piezoelectric element 2, and a constant output change of the detecting unit 4. A printer control unit 7 that issues a warning signal when the amount exceeds the limit, and an input / output unit 9 that reports a warning signal issued from the printer control unit 7 to the host device 20. Printer control unit 7
A printing unit 6 for urging the thermal head 5 to perform a predetermined printing operation, and a warning unit 8 for issuing a warning to an operator.
Is attached.

The detection unit 4 includes an A / D converter, and the printer control unit 7 uses the output voltage of the piezoelectric element 2 as a digital signal.
To enter. The printer control unit 7 has a microcomputer, compares the output voltage of the piezoelectric element 2 with a threshold value, outputs a warning signal to the warning unit 8 and the input / output unit 9 according to a processing program prepared in advance, Controls start / stop of printing operation. The warning unit 8 is an LED indicator provided on an operator panel.

On the other hand, the host device 20 is the printer device 10.
An input / output unit 21 for receiving a warning signal reported from the input / output unit 9 of the above, and a warning unit 23 for issuing a warning to an operator,
The warning signal is received by the input / output unit 21 and the warning unit 23
And a CPU 22 for issuing a warning. Host device 2
Reference numeral 0 denotes a computer, and the warning unit 23 is a display monitor. When receiving the warning signal, the CPU 22 displays an error message on a display to urge the operator to perform a warning.

Next, the overall operation of this embodiment will be described with reference to FIG.

The head heating element 1 of the thermal head is used in close contact with an ink ribbon or a sheet. When foreign matter such as dust enters between the head heating element 1 and the ink ribbon or the like, as shown in FIG. 3, a part of the head heating element 1 is pressed and a corresponding part of the piezoelectric element 2 receives pressure. As a result, a change occurs in the voltage of the piezoelectric element 2 detected by the detection unit 4 and input to the printer control unit 7. When the change in the output voltage of the piezoelectric element 2 exceeds a predetermined amount with respect to the normal state, the printer control unit 7 determines that foreign matter such as dust has entered between the head heating element 1 and the ink ribbon. Then, the printing operation by the printing unit 6 is stopped, and a warning signal is issued to the warning unit 8 and the input / output unit 9. As a result, the warning LED indicator of the printer device is turned on, an abnormality is reported to the operator, and a warning signal is output from the input / output unit 9 to the host device 20. And
When the input / output unit 21 of the host device 20 receives the warning signal,
The CPU 22 displays an error message indicating “dust mixing abnormality” on the display monitor of the warning unit 23 to notify the operator of the abnormality.

As described above, according to this embodiment, since the piezoelectric element is interposed between the heat-resistant substrate of the head body 3 and the heating resistor of the head heating element 1, foreign matter such as dust is prevented from entering the piezoelectric element. 2 can be detected as a change in the output voltage. Further, when the contamination is detected, the printer control unit 7 issues a warning signal, so that the contamination can be promptly reported to the operator. In particular, when the higher-level device 20 receives the warning signal, the CPU 22 issues a warning such as an error message to the warning unit 23 of the higher-level device. And prompt action can be taken to cancel the abnormality. In addition, since the printer control unit 7 of the printer device 10 issues a warning signal and stops the printing operation by the printing unit 6, it is possible to immediately prevent issuance of illegal securities or cash notes due to poor printing.

The piezoelectric element may be installed at any position as long as it is located between the substrate and the heating resistor.

[0022]

The present invention is constructed and functions as described above. According to this, the piezoelectric element is interposed between the heat-resistant substrate and the heating resistor, so that foreign matter such as dust can be prevented from entering the piezoelectric element. Can be detected as a change in the output voltage.

According to the second aspect of the invention, the printer control section issues a warning signal when foreign matter is detected.
It is possible to promptly report the entry of foreign matter to the operator.

According to the third aspect of the present invention, when the host device receives the warning signal, the control unit of the host device issues a warning to the warning unit. Therefore, the operator operating the host device also detects the foreign matter generated in the printer device. It is an unprecedented advantage that it is possible to know the contamination early and to promptly take a corrective action for clearing the abnormality, and to promptly prevent the issuance of fraudulent securities or cash vouchers with printing defects. It is also possible to provide a thermal printer, a printer device using this thermal head, and a printer system using this printer device.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a thermal head showing one embodiment of the present invention.

FIG. 2 is a block diagram of a printer system showing an embodiment of the present invention.

FIG. 3 is a diagram illustrating the principle of detecting dust in the thermal head shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating resistor 2 Piezoelectric element 3 Head main body 4 Detecting unit 5 Thermal head 6 Printing unit 7 Printer control unit 8 Warning unit of printer device 9 Input / output unit of printer device (output unit of warning signal) 10 Printer device 20 Host device 21 Input / output unit of higher-level device (reception unit of warning signal) 22 CPU (control unit of higher-level device) 23 Warning unit of higher-level device D Dust

Claims (3)

[Claims] 1. A thermal head in which a heat-generating resistor is integrated on a heat-resistant substrate such as an alumina substrate, wherein a piezoelectric element is interposed between the heat-resistant substrate and the heat-generating resistor. . 2. A thermal head according to claim 1, a detector for detecting the output voltage of the piezoelectric element, and a printer for issuing a warning signal when the output change of the detector exceeds a preset constant amount. A printer device, comprising: a control unit; and an output unit for notifying a host device of a warning signal issued from the printer control unit. 3. The printer device according to claim 2, and a host device that outputs print data to the printer device, wherein the host device receives a warning signal notified from an output unit of the printer device. A printer system comprising: a section, a warning section for issuing a warning to an operator, and a control section for receiving a warning signal at the receiving section and issuing a warning to the warning section.