JPH06253094A - Facsimile equipment - Google Patents

Abstract

PURPOSE:To prolong the service life of a facsimile equipment at the time of using a battery by providing a control means for reducing the number of drivers driven simultaneously as a system for reducing a driving current for recording pictures. CONSTITUTION:A printer control circuit 1 transfers recording signals DT by one line to a shift register 2 in synchronism with shift clocks CK. At this time, as the recording signals DT, the formal recording signals of only the respective halves of four groups are transferred. When transfer is ended, latch signals LT are outputted and the recording signals of the shift register 2 are stored in a latch circuit 3. Simultaneously, the strobe signals STB1 of a fixed pulse width T are outputted. The number of the drivers driven at this time is n/2 which is the half of D1-D1n. When the output of the signals STB1 is ended, the strobe signals SBT2 of the same pulse width T are outputted. Similarly thereafter, the signals STB3 and STB4 are successively outputted and recording operations are performed. The next recording signals DT are transferred as white data before a first recording operation is ended and recording for one line is performed in a second operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile apparatus which reduces a driving current for recording an image.

[0002]

2. Description of the Related Art At present, a thermal recording apparatus using a thermal line head is widely used as an image recording apparatus for a facsimile machine. Hereinafter, a thermal recording device which is often used in a facsimile device will be described with reference to the drawings.

FIG. 1 shows an example of a thermal recording device (hereinafter referred to as a printer) which is often used in a facsimile machine. In FIG. 1, a printer control circuit 1 controls the operation of the printer. 2 is a shift register, which is a shift clock C from the printer control circuit 1.
The recording signal DT output in synchronization with K is for recording one line. A latch circuit 3 is for latching and holding the recording signal input from the shift register 2 by the latch signal LT output from the printer control circuit 1. D _{1 to} d _4n are drivers for driving the heating resistors R _{1 to} R _4n , respectively, and the whole thereof is divided into four groups of n. STB1~STB4 the strobe signal, it is input to one terminal of each of the groups of drivers D ₁ to D _4n, it is for controlling the drive of the heating resistor.

With respect to the printer configured as described above,
The operation will be described below. Figure 2 shows the basic recording operation.
It is performed in the form as shown in (a) to (g). That is, the printer control circuit 1 sends the recording signal DT to the shift clock C.
The data is transferred to the shift register 2 in synchronization with K. When the transfer of the recording signal DT for one line is completed, the latch signal LT is output to transfer the recording signal of the shift register 2 to the latch circuit 3.
To memorize. At the same time, the strobe signal STB1 having a constant pulse width T is output. When the output of the strobe signal STB1 is completed, the strobe signal STB2 having the same pulse width T is then output. At the same time, the strobe signals STB3 and STB4 are sequentially output at the same time. In addition, before the recording of one line is completed, the recording signal DT of the next line is
Are transferred to the shift register 2. In this way, the image is printed on the recording paper line by line. Therefore, the drive current for recording an image is generated by the heating resistors R ₁ to
Since R _4n is divided into four groups, the number of drivers D _{1 to} D _4n simultaneously driven is n, which is n times the current I flowing through one heating resistor.

[0005]

However, since the above-mentioned recording method requires a large amount of drive current for recording an image, power is supplied from a battery like a portable facsimile apparatus which has been put into practical use in recent years. In the facsimile machine, when image reception occurs continuously, the battery is consumed so much that the usable time of the facsimile machine is short.

The present invention solves the above-mentioned conventional problems and provides a facsimile apparatus capable of extending the usable time when power is supplied from a battery.

[0007]

In order to achieve this object, the facsimile apparatus of the present invention has a method of reducing the drive current for recording an image when recording a received image. The control means for reducing the

[0008]

With this structure, the driving current for image recording can be reduced and the maximum required current can be reduced. Therefore, when the power is supplied from the battery, the consumption of the battery can be reduced and the usable time can be extended. be able to.

[0009]

The operation of one embodiment of the present invention will be described below with reference to the drawings. In the thermal recording apparatus which is often used in the facsimile apparatus shown in FIG.
Image recording is performed in the forms shown in (a) to (g).
That is, the printer control circuit 1 transfers the recording signal DT for one line to the shift register 2 in synchronization with the shift clock CK. However, the recording signal DT at this time is 4
The heating resistors divided into one group are each further divided into two, half of which transfers the data as white data. That is, in each of the four groups, only half of the normal recording signals are transferred. When the transfer of the recording signal DT is completed, the latch signal LT is output and the recording signal of the shift register 2 is stored in the latch circuit 3. At the same time, the strobe signal STB1 having a constant pulse width T is output. The number of drivers driven at this time is (1/2) n, which is a half of D _{1 to} D _1n . When the output of the strobe signal STB1 ends,
Next, the strobe signal STB2 having the same pulse width T is output. Similarly, the strobe signals STB3, STB4
Are sequentially output. In this way, when the recording operation is completed once, the latch signal LT is output again and the strobe signals are sequentially output from STB1 to STB4 to perform the recording operation. At this time, the next recording signal DT is transferred to the shift register 2 before the first recording operation is completed. The recording signal DT at this time transfers the amount transferred as white data last time as the normal data, and the amount transferred as the previous normal data as the white data. In this way, the recording image for one line is printed on the recording paper by the two recording operations.

As described above, according to this embodiment, the image recording
Drive current for drive D is driven simultaneously₁~
D_4nIs D₁~ D_1n, D₂~ D_2n, D₃~ D_3n, D_Four
~ D _4n(1/2) n of each half of
Can be half of the scheme.

[0011]

As described above, according to the present invention, the driving current for image recording can be reduced by dividing the image recording of one line into two and reducing the number of drivers to be driven at the same time. Therefore, when the power is supplied from the battery, the consumption of the battery can be reduced and the usable time can be extended, and its practical effect is great.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of a thermal recording device.

FIG. 2 is an operation waveform diagram showing a conventional recording operation.

FIG. 3 is an operation waveform diagram showing a recording operation of the present invention.

[Explanation of symbols]

 1 Printer control circuit 2 Shift register 3 Latch circuit

Claims (1)

[Claims] 1. In a facsimile apparatus having a thermal recording device using a thermal line head as a recording means and capable of supplying power by a battery, the number of drivers to be driven simultaneously is reduced when recording a received image. A facsimile apparatus comprising control means for reducing a drive current for image recording.