JPH04183167A - Printer - Google Patents

Abstract

PURPOSE:To reduce electric power consumption for printing to lengthen a period of time for battery driven printing by operating an electric power saving command generating means as required to set on a power saving mode. CONSTITUTION:When during printing by a battery driving facsimile unit, the battery voltage drops below a reference value, a battery voltage detecting circuit 20 detects this condition and sends a power saving mode command to a pulse signal control means 19. In order to do this, the pulse width of a pulse signal to a print head is shortened from t1 to t2. Thus, power consumption in the printing head is reduced as much as the shortened pulse width, being able to lengthen a period of time for printing. Accordingly, the printer can be protected from stopping due to running out of battery power during the execution of print operation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a printing device used, for example, in facsimile machines.

(Prior Art) Some facsimile machines include battery-powered types that use a rechargeable battery as a power source.

Naturally, in such a facsimile machine, if the operating state continues, the battery will be consumed, and when the battery capacity decreases and reaches a limit range, functions such as communication functions and copying will stop. In particular, a large amount of power is consumed for printing during reception and copying, and the battery capacity is significantly reduced. Therefore, these operations may stop during reception or copying. That is, it is difficult to use the printer for printing for a long time, and when receiving a large number of documents, the printer stops midway as described above.

(Problems to be Solved by the Invention) As described above, the power consumption during printing is large, and in the case of battery drive, the battery runs out relatively early, causing a situation where printing stops midway.

SUMMARY OF THE INVENTION An object of the present invention is to provide a printing device that can set a power saving mode as necessary, and that does not cause a situation such as a stoppage in the middle of operation due to battery exhaustion, even when it is powered by a battery. It is in.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a print head that performs a printing operation when a pulse signal of print data is input, a power-saving mode command generation unit that generates a power-saving mode command, and a power-saving mode command generating means for generating a power-saving mode command. The apparatus further includes pulse signal control means for reducing the power of the pulse signal input to the print head in response to an input of a command compared to normal times.

(Function) In the present invention, by operating the power saving mode command generating means as necessary and setting the power saving mode, the power of the pulse signal of the print data is controlled to be lower than the normal power, so the power required for printing is controlled to be lower than the normal power. It is possible to reduce consumption and perform power-saving operation. Therefore, in the case of battery drive, the printable time can be extended.

(Example) Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

First, the overall structure of the facsimile machine will be explained with reference to FIG. In the figure, 11 is the main body of the facsimile machine;
At the top of the diagram is an insertion slot 1 for sending originals and receiving recording paper.
2 is formed. Further, on the front edge of the upper surface, operating keys 13, a liquid crystal display 14, etc. are provided. Furthermore, a mounting portion 16 for the battery 15 is provided at the rear edge of the upper surface.
is formed.

The battery 15 is of a rechargeable type, and when installed in the mounting section 16, it supplies power to an NCU circuit (not shown) provided in the main body 11, a modem, a CPU, a printing section, etc. to be described later.

Next, the present invention will be explained in detail with reference to FIG. Reference numeral 18 denotes a print head that performs predetermined printing on recording paper based on print content (image signals) output from a receiving section (not shown), and a known thermal head is used. This print head 18 is heated by inputting a pulse signal with a pulse width t1 as shown in FIG. 3, and performs a printing operation.

Reference numeral 19 denotes a pulse signal control means that changes the pulse width t1 of the pulse signal shown in FIG. 3 to a narrower pulse width t2 shown in FIG. It is.

A battery voltage detection circuit 20 monitors the voltage of the battery 15 and outputs a detection signal when the voltage falls below a preset reference voltage. This detection signal passes through the OR game 21 and is then inputted to the pulse signal control means 19 as a power saving mode command. Reference numeral 22 denotes an external input switch, which is turned on by a user's operation, and its output signal passes through the OR gate 21 and is similarly input to the pulse signal control means 19 as a power saving mode command. That is, these battery voltage detection circuit 20 and external input switch 22 function as power saving mode command generation means 23.

Next, the operation of this embodiment will be explained.

When a facsimile machine is powered by a battery, the print head 18 operates during reception and copying, which consumes a lot of power (if this state continues for a long time, the battery capacity will drop significantly relatively quickly). Therefore, the battery 15 may become completely discharged during reception or copying, and the operation may stop.

Therefore, the present invention switches to a power saving mode based on conditions such as the battery condition and the number of pages printed, thereby prolonging the decline in battery capacity and preventing the above-mentioned operation stoppage during reception or copying. .

That is, when the voltage of the battery 15 becomes lower than the reference voltage due to a decrease in the capacity of the battery 15 during a printing operation, the battery voltage detection circuit 20 detects this and issues a power saving mode command to the pulse signal control means 19. Therefore, the pulse signal control means 19 shortens the pulse width of the pulse signal to the print head 18 from the previous value t shown in FIG. 3 to the pulse width t2 shown in FIG. 4. When the pulse width is shortened in this manner, the power consumed in the print head 18 is reduced by the shortened pulse width, making it possible to print for a longer time. Therefore, it is possible to prevent the operation from being stopped due to battery exhaustion during printing.

Note that when the pulse width is shortened, the print density becomes lighter.

Therefore, the pulse width is controlled to such an extent that the print is legible.

Furthermore, even if the battery capacity has not decreased enough to cause the battery voltage detection circuit 20 to operate, if it is determined in advance that the amount of print data is large, the external input switch 22
is turned on to input a power saving mode command to the pulse signal control means 19. In this case as well, the pulse width of the printing pulse signal is controlled to be short, and the current consumed in the print head 18 is reduced. Therefore, it is possible to prevent the operation from stopping due to battery exhaustion during printing, which is a concern when printing a large amount of data.

Although the above description has been made using a battery-powered facsimile machine as an example, the present invention can of course also be applied to operation of a facsimile machine in a power saving mode using a normal commercial power source. In this case, only the external input switch 22 may be used as the power saving mode command generating means 23, and the switch 22 may be turned on at the user's discretion to switch to the power saving mode.

Furthermore, although the pulse signal control means 19 controls the pulse width, it may also control the pulse height.

〔Effect of the invention〕

According to the present invention, since the power of the pulse signal of the print data is reduced as necessary, it is possible to reduce the power consumption in printing which requires a large amount of power, and a large power saving effect is produced. Therefore, in the case of a battery-driven type, it is possible to print for a longer time, and it is possible to effectively prevent operation stoppage due to battery exhaustion during printing.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a facsimile machine showing an embodiment of the printing device of the present invention, Fig. 2 is a perspective view showing the overall structure of the facsimile machine, and Figs. 3 and 4 show the pulse width for printing in normal times. 12 is a time chart showing the relationship between pulse width and pulse width in power saving mode. 18...Print head, 19...Pulse signal control means, 2
3. Power saving mode command generation means. Inventor: November 19, 1990 1) True
Shun Akitsu
-Patent applicant Tokyo Electric Co., Ltd. -Mineko 1-

Claims (1)

[Claims] (1) A print head that prints based on the input of a pulse signal of print data; a power-saving mode command generation means that generates a power-saving mode command; and when this power-saving mode command is input, the power-saving mode command is input to the print head. 1. A printing device comprising: pulse signal control means for reducing the power of a pulse signal generated compared to normal times.