JPS58219072A - Heat-sensitive recording system - Google Patents

Abstract

PURPOSE:To enable to minimize electric power capacity, by conducting a heat-sensitive recording while prolonging a minimum scanning recording period and an electric power impressing period in accordance with the detected temperature of the ambient atmosphere or a heat-sensitive recording head becomes lower, in a facsimile device. CONSTITUTION:When reading and transmitting, a copy read signal generated by a reading part 3 is momentarily stored in a memory 2, and is transmitted through a modulation, demodulation and circuit controlling part 11 by compressing the band. On the other hand, when receiving and recording, a facsimile signal passed through the controlling circuit 11 is momentarily stored in the memory 2, is then converted into a predetermined signal constituting recording data, which selectively drive heat-sensitive recording elements to generate heat, thereby recording. The temperature of the heat-sensitive recording head 5 is detected by a sensor 6, the detection signal is passed through a buffer amplifier 7 and an analog-to-digital converter 8, and heat-sensitive recording is conducted with the minimum scanning recording period and the electric power impressing period set to be longer as the temperature is lower by an MPU1. Accordingly, the electric power capacity of a power source for heating the head can be restricted to a required minimum value, and favorable heat-sensitive recording can be accomplished even at a low temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermal recording method in a facsimile machine, and particularly to a thermal recording method that minimizes the power capacity of a heating power source for a thermal recording head and performs thermal recording in good condition even in a low-temperature environment. The invention relates to a heat-sensitive recording method.

In the thermal recording method, recording is performed by heating the thermal recording paper with a thermal recording head and applying heat to the recording paper that exceeds the color development temperature unique to the recording paper. However, there is a problem in that the power capacity of the power supply for heating the thermal recording head must be increased.

In other words, the temperature of a thermal recording head is generally determined by the head temperature at that time, the amount of recording power applied to the head, (=applied power per unit time x applied time) the material of the head, etc., but according to international standards (So-called CCITT standard), the minimum scanning recording time per line (hereinafter simply referred to as MELT) is predetermined, so in order to perform thermal recording in good condition, the smaller the MELT, the better. Furthermore, the more thermal recording is performed in a low-temperature environment, the more a thermal recording head heating power source with a large power capacity is required. To explain this in more detail, the amount of power applied to the thermal recording head is generally adjusted by controlling the application time, and the application time is shortened when the ambient temperature is high. However, if the ambient temperature is low, the application time must be increased. Therefore, a high-speed fixed MSLT type machine with a limited application time inevitably requires a large-capacity heating power source. Facsimile machines are generally installed indoors, and the ambient temperature in which they are used is approximately 5°C to 35°C, but in order to obtain a predetermined recording density, for example, at 5°C, the temperature is 30°C to 35°C, compared to 10°C. As much as 50% more electricity is required.

In addition, in thermal recording type facsimile machines, according to the above standards, prior to exchanging facsimile signals with the other party's device, the other party's
Although the SLT is supposed to be sent, the MSLT
The reality is that this is uniquely determined for each device. According to the standard, standard M8LT is 20m5, and ob-
/=i y is 10m5°5mSs40ms, but the fact that the MSLT is fixed to one of these is also a cause of increasing the capacity of the heating power source. M
This is because the smaller the SLT value is, the faster recording is performed and the more power is required. In a facsimile machine designed in this way, the heating conditions are relaxed under conditions such as standard room temperature, and by reducing the recording time, the facsimile machine does not use its full power.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a thermal recording method which can suppress the electric power capacity of a heating power source for a thermal recording head to the necessary minimum and can perform thermal recording in good condition even when the ambient temperature is low.

For this purpose, the present invention detects the ambient atmosphere temperature or the temperature of the thermal recording head, and the lower the detected temperature, the more the MELT
Thermal recording is performed by increasing the value of . That is, when the value of MSLT is made large, the power application time can also be increased, and therefore the power capacity of the heating power source can be reduced to the necessary minimum,
Furthermore, it is possible to perform thermal recording in good condition even at low temperatures.

The present invention will be explained below with reference to FIGS. 1 and 2.

First, FIG. 1 shows a schematic configuration of a facsimile apparatus according to the present invention. According to this, the device in this example is microcomputer controlled, and the MPU bus 9 has an MPUI, a memory 2, a reading section 3, a thermal recording section 4, an input/output section (control signal input/status (for display) 10 and a modulation/demodulation/line control section 11 are accommodated and connected.

Normally, when reading and transmitting, the recorded original reading signal from the reading section 3 is partially stored in the memory 2 line by line, and then transmitted via the modulation/demodulation/line control section 111 and the external line terminal 12 in a predetermined band compressed state. It is now sent as a facsimile signal over the wire.

Also, during reception and recording, the facsimile signal from the other party's side from the line is transferred to the outside line terminal 12, the modulation/demodulation/line control unit 11
After a portion of the data is stored in the memory 2 via the memory 2, it is converted to a predetermined value as recorded data. Thermal recording is performed by selectively driving the thermal recording elements constituting the thermal recording head 5 to generate heat based on the line-corresponding converted recording data.

By the way, the facsimile apparatus according to the present invention is provided with means for detecting the ambient atmosphere temperature or the temperature of the thermal recording head, and the MPUI calculates or selects the MSLT based on the detected temperature data from the means. As shown in the figure, in this example, the temperature of the thermal recording head 5 is detected by a temperature sensing element 6, and the temperature detection signal is digitally converted by an A/D converter 8 via a buffer amplifier 7. The temperature of the recording head 5 can be known. The MPUI calculates the MSLT based on the detected temperature data, or obtains the required MELT by reading out the MELT from a table stored in advance in the memory 2 using the data as an address.

FIG. 2 shows the overall control processing flow by the MPU 1 during reception and recording. According to this, when reception is activated manually or automatically, the MPU 1 first learns the ambient atmosphere temperature or the temperature of the thermal recording head. 1 Temperature Sense" is this process. Once the temperature is known, the next step is to calculate or select the MSLT. However, with some exceptions, the MSLT value to be calculated or selected is generally the one that has already been used. According to the standards mentioned above, standard M
10mg as an option in addition to ELT (20mg).

Since MELT with values of 5ms and 40m5 is approved, one of these values will generally be used as M8LT, except in special cases.

The MELT obtained as described above is sent to the other party's device using the pre-facsimile procedure (handshake signal). From then on, MPtll performs thermal recording while variably controlling the power application time within the range of M8LT. It is something that becomes. Thermal recording is performed by increasing the amount of power applied at low temperatures and decreasing the amount of power applied at high temperatures, but the MELT value is not fixed but variable, and furthermore, at low temperatures Therefore, it is possible to perform thermal recording in good condition even at low temperatures while minimizing the power capacity of the head heating power source.

As explained above, in the present invention, the lower the detected ambient atmosphere temperature or the temperature of the thermosensitive recording head, the longer the MELT and power application time to perform thermographic recording. Furthermore, in the case of the present invention, the power capacity of the head heating power source can be suppressed to the necessary minimum, and the effect of thermal recording can be performed in good condition even at low temperatures, which is 5x.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a schematic configuration of a facsimile apparatus according to the present invention, and FIG. 2 is a diagram showing the overall control processing flow by the microprocessor during reception and recording. 1...-MPU, 2...Memory, 3...Reading section, 5
...Thermal recording head, 6...Temperature detection element, 8...
- A/D converter, 11...modulation/demodulation/line control section. Agent Patent Attorney Masami Akimoto Figure 1 Figure 2

Claims (1)

[Claims] Prior to thermal recording, the ambient atmosphere temperature or thermal recording head temperature is detected, and the lower the detected temperature, the longer the minimum scanning recording time is and the longer the minimum scanning recording time is sent to the other party. A thermal recording method characterized by performing thermal recording while controlling such that the lower the temperature, the longer the time for applying power to the thermal recording head within a minimum scanning recording time range.