JPS6021415A - Thermal recorder - Google Patents

Abstract

PURPOSE:To facilitate the discrimination of input signals, which are close to each other and to prevent the deterioration of a heating element of a thermal head, by recording one signal in a red color when the difference in two input signals is lower than a specified value, and recording the signals in a black color at the opposite case. CONSTITUTION:A difference detecting part 1 always detects the difference between two input signals (i) and (j). When the difference exceeds the reference value from a reference-value generating part 2, a normal mode is outputted. At this time, one color recording of both signals is performed in a black color, at which a driving current for a heating element is small. When the difference signal becomes lower than the reference value, a comparator 3 is inverted from the normal mode, and a special mode is outputted. At this time, the recording of one signal is performed in a red color, at which the driving current for the heating element is large, and the recording of the other signal is performed in the black color. Thus the discrimination of the input signals, which are close to each other, can be facilitated, and the deterioration of the heating element of a thermal head 14 can be prevented.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a thermal recorder, and particularly to a thermal recorder that performs one-color black recording under normal conditions and performs two-color recording only when two signals are close to each other. Regarding type recorders.

[Technical background of the invention and its problems]

In a thermal recorder, it is possible to record in a color other than the standard color by changing the drive current of the heating element of the thermal head, but in general, it is possible to record in a color other than the -color. In order to do this, the heating element must be driven with a large current, and there is a problem in that if the heating element is driven at high temperatures for a long period of time, the life of the heating element will be significantly shortened.

For this reason, at present, analog waveforms of input signals are recorded using one-color recording, and it is therefore difficult to distinguish when waveforms that are close to each other are recorded.

[Purpose of the invention]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a thermal recorder that allows two waveforms to be easily distinguished when they approach each other, and that causes almost no deterioration of the heating element of the thermal head.

[Summary of the invention]

The present invention constantly detects the degree of proximity of two input signals, that is, the difference between both signal values, and compares this difference with a predetermined one-step value using a comparator. , both signals continue to be recorded in one color in black, where the driving current of the heating element is small, and one signal is recorded in red only when the difference between both signals becomes less than the 1 pair value. If the state returns to the exceeded state, the system returns to one-color black recording and continues, thereby limiting the high current drive of the heating element of the thermal head to only the singular state.
The intended purpose was achieved by preventing its deterioration.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of a thermal recorder according to an embodiment of the present invention.

In Figure 1, (1) is a difference detection unit that detects the difference between two input signals i and j, and (2) is a reference value generator that outputs a predetermined minimum value of the difference between both signal values as a reference value. Department,
(3) is a comparator that compares the reference value from the reference value generator and the difference signal from the difference detector, and inverts the output from the normal mode to the singular mode only when the difference signal is less than the reference value.

(7) tj: AD converter that converts the input signal i'iAD; (8) is the AD converter (input digitized input (n); a signal indicating the phase of the thermal head corresponding to the signal value; a first recording control unit that outputs
(9) is an AD converter that AD converts input signal j, 0
[ is a second recording control unit which inputs the input signal j digitized by the AD converter (9) and outputs a signal indicating the phase of the thermal head corresponding to the signal value.

(4) is a black coloring pulse generator that outputs pulses for black recording; (5) is a red coloring pulse generator that outputs pulses for red recording;
6) receives the output from the comparator (3) as well as inputs the black coloring pulse and the red coloring pulse, and when the output is in normal mode, it passes the black coloring pulse, and when it is in the singular mode, it passes the red coloring pulse. This is the gate switching section that allows the passage through.

(11) receives the coloring pulse from the black coloring pulse generator (4) and outputs a black coloring pulse that drives the heating element of the corresponding phase of the thermal head based on the signal from the first recording control unit (8). This is a first head driving section.

(121 receives the coloring pulse that has passed through the gate switching unit (6), and outputs the coloring pulse that drives the heating element of the corresponding phase of the thermal head based on the signal from the second recording control unit α. This is the second head drive section.

I is a fixed thermal head, and the first head driving section α
→ and the second head drive unit (1) are connected to each other via an OR circuit 3, and upon receiving the coloring pulses from both head drive units, input them to the two-color thermal recording paper by driving heating elements with corresponding phases. Record the signal.

In the thermal recorder according to the embodiment of the present invention configured as described above, the difference detection section (1) detects two input signals i.
The degree of approach between and The difference value is compared with the minimum value, and the normal mode is output while the current difference value exceeds the reference value. Gate switching section (6)
While the output from the comparator (3) is in the normal mode, the black coloring pulse from the black coloring pulse generator (4) is passed through and inputted to the second head drive unit (first head drive unit 0υ). A black coloring pulse is always input.

As a result, the first head driving section (11) adjusts the phase of the thermal head α based on the signal indicating the phase of the thermal head corresponding to the input signal i from the first recording control section (8). It outputs a signal for driving the heat generating element with a black coloring pulse, while the second head driving section 11 outputs a signal that drives the heating element with a black coloring pulse, while the second recording control section (IQ) outputs a signal indicating the phase of the thermal head corresponding to the input signal j from the IQ. , a signal b is applied to drive the heating element of the thermal head αa of the corresponding phase with a black coloring pulse.These two coloring pulse signals are sent to an OR circuit (13
The thermal head (14
Heating elements corresponding to input signals i and j of 1 are driven with a predetermined small current to record black on two-color thermal recording paper,
Input signals i and j are recorded in black.

When the difference between the two input signals becomes less than the reference value, the comparator (3
) inverts the normal mode and outputs the singular mode.

As a result, the gate switching unit (6) passes the red coloring pulse and inputs it to the second head drive section 0 α. As a result, only the second head drive section α switches to red coloring pulse drive, and the thermal head (14 ) outputs a signal that drives the heating element with the corresponding phase with a red coloring pulse. This red coloring pulse signal and the black coloring pulse signal related to the input signal i from the first head driving unit aυ are combined by the OR circuit (13), and from this, the heating element corresponding to the input signal i of the thermal head Q4 is , is driven by a predetermined small current for black recording to record the input signal i in black on the two-color thermal recording paper, while the heating element corresponding to the input signal j of the thermal head (14) is driven by a predetermined small current for red recording. Driven by large current 2
Record the input signal jk in red on color thermosensitive recording paper.

Recording was performed using the two recording operations described above.
Figure 2 shows the color thermosensitive recording paper α powder. In Figure 2, 1
The main line indicates a black record, and the two lines indicated by the code 20 indicate a red record.Only when the difference between both input signal values is less than a certain value, that is, when they approach within a certain distance, only one signal is activated. 1. Indicates the state in which black recording is switched to red recording. ing. This makes it easier to distinguish between closely spaced input signals.

When the difference between the input signals exceeds a certain value (KfD), the comparator (3) switches to the normal mode.
The gate switching unit (6) is switched to pass the black coloring pulse, and the second head drive unit (12) returns to black coloring pulse drive, and as a result, the input signal j returns to black recording, and both internal input signals are black. The Isshiki style returns to 0.

In this way, since the abnormal state of the TAIDC bIC drive k'lQj of the heat generating element of the thermal head is brought to an untimely limit, deterioration of the heat generating element can be prevented.

〔Effect of the invention〕

As described in detail above, according to the present invention, in a thermal recorder, the degree of approach of two input signals, that is, the difference between both signal values is always detected, and this difference is set to a predetermined constant value by a comparator. As long as the difference exceeds a certain value, both signals continue recording in one color in black, where the driving current of the heating element is small, and only when the difference between both signals becomes less than a certain value, one of the signals is recorded. By recording the signal in red and returning to the state where the difference between the two signal values exceeds a certain value, it returns to recording in one color in black and continues, the high current drive of the heating element of the thermal head is Since both signals are limited to a singular state in which they are close to each other within a certain distance, deterioration due to high-temperature driving of the heating element is prevented and the function of the thermal head is maintained for a long time.In addition, signal waveforms that are close to each other are recorded in different colors. It is possible to obtain a thermal recorder that is easy to distinguish.

[Brief explanation of the drawing]

FIG. 1 shows the configuration of a thermal recorder according to an embodiment of the present invention.
The block diagram, FIG. 2, is a plan view showing two-color thermal recording paper on which recording is performed by the recorder of FIG. 1. 1... Difference detection unit 2... Reference value generation unit 3... Comparator 4... Black coloring pulse generator 5... Red coloring pulse generator 6... Gate switching unit 7, 9... AD Converter 8...First recording control section lO...Second recording control section 11...First head drive section 12...Second head drive section 13...OR circuit ■4.・Thermal Head 15 ・Two-color thermal recording paper agent Patent attorney Inoue - Male

Claims (1)

[Claims] a difference detection unit that detects the difference between two input signals; a reference value generation unit that outputs a predetermined minimum value of the difference as a reference value; and a reference value from the reference value generation unit and the difference detection unit. a comparator that compares the difference signals of and inverts the output from normal mode to singular mode only when the difference signal is less than a reference value;
an AD converter that performs AD conversion on one input signal; a first recording control section that receives a digitized input signal from the AD converter and outputs a signal indicating the digit of the head corresponding to the signal value; A to transform the input signal
A D converter, a second recording control unit which receives a digitized input signal from the AD converter and outputs a signal indicating the digit position of the head corresponding to the signal value, and a second recording control unit for performing black recording. A black coloring pulse generator that outputs a pulse, and a black coloring pulse generator that receives the coloring pulse from the black coloring pulse generator and drives all heating elements of the corresponding digit of the thermal head based on a signal from the first recording control section. A first head drive unit outputs a coloring pulse, a red coloring pulse generator outputs a pulse for recording red color, and the red coloring pulse and the black coloring pulse are inputted, and all outputs from the comparator are inputted. a gate switching section that passes the black coloring pulse when the output is in the normal mode and passes the red coloring pulse only when the output is in the singular mode; a second head driving section that outputs the coloring pulse that drives the heating element of the corresponding digit of the thermal head based on a signal from the second recording control section; this second head driving section and the first head; A thermal head which is connected to a drive unit and which records all input signals on two-color thermal recording paper by receiving coloring pulses from both head drive units and driving heating elements of corresponding digits to record all input signals on two-color thermal recording paper. Type recorder.