JPS6249766A - Thermal head - Google Patents

Abstract

PURPOSE:To perform recording of one line quantity under an optionally divided condition, by connecting the parallel outputs of a shift register with the ENB (power supplying time controlling signal) input controlling gate of each driving element. CONSTITUTION:Picture signals of one line quantity are inputted from a PiX input terminal 3 and transferred to the 1st shift register 5 of driving elements 40a-40x by means of a PcK (transfer clock) signal inputted from a PcK input terminal 4. When the number of the ICs of the driving elements is 32 and quartered driving is performed, SELs (select signal) which are to be inputted to the SEL input terminals 32 of the first eight ICs are made to be turned on. After the storage is completed, an ENB signal which is inputted from an ENB input terminal 1 and controls a power supplying time is outputted and recording of 1/4 line is performed in the first place. Then an ESL signal is inputted to the 2nd shift register 43 from an ESL input terminal 41 so that the SELs which are to be inputted to the SEL input terminals 32 of the next eight driving elements can be turned on.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a thermal head of a heat-sensitive recording device used, for example, in a facsimile machine.

BACKGROUND ART Conventionally, as shown in FIG. 3, a thermal head in a thermal recording apparatus of this type has a large number of heat generating resistors 21 arranged in a row, and The drive element 20 is generally composed of a drive element 2o that is selectively driven, and as shown in FIG. It consisted of an AND gate 7, a latch circuit, etc., and a shift register 5. That is, the driver 8
is mainly composed of a large number of switching elements, one end of which is connected to the heating resistor 21 through the output terminals 9a to 9x, while the other end is connected to the power supply terminal 11. The shift register 5 is connected to the power supply 13 via the driver 8.
The image signal (hereinafter abbreviated as PiX) recorded by the heating resistor 21 for one line, which is configured with the same number of bits as the number of switching elements, and is input through the input terminal 3, is input to the input terminal 4. In accordance with the image signal transfer lock (hereinafter abbreviated as PcK) inputted through the image signal transfer lock, the image signal is sequentially transferred and stored, and the final bit PiX can be output from the output terminal 10. After the one line of PiX transferred to the shift register 5 is stored, it is transferred to the timing latch circuit 6 for a strobe signal (hereinafter abbreviated as STB) input via the input terminal 2 and latched. A signal (hereinafter, EN
The switching elements of the driver 8 are selectively turned on according to the supplied PiX. Each of the heating resistors 21 is selectively energized to generate heat.

Furthermore, each of the heating resistors 21 is driven. The drive element 20 is usually configured in units of 32 bits or 64 bits, and in practice, one line of recording is divided into a plurality of blocks in order to prevent an increase in the recording power capacity. In the figure, ENB is
By inputting four ENBs 1 to 4 in parallel and connecting 1/4x each of ENBs 1 to 4 to X drive elements 20a to 20x, one line is divided into four and driven.

Problems to be Solved by the Invention However, in the conventional thermal head described above, the number of divided recordings for one line is limited by the ENB wiring, and the number of divided recordings for one line can be arbitrarily changed in one thermal head. The problem was that I couldn't do it.

Furthermore, it is possible to deal with such a problem by inputting as many ENBs as the number of drive elements in parallel so that there is a one-to-one correspondence between ENB and each of the drive elements 20a to 20x. However, with such a countermeasure, a new problem arises in that the interface section that connects the thermal head with the outside becomes larger.

Purpose of the Invention The present invention has been made in view of the above-mentioned problems, and it is possible to record one line in arbitrary divisions without increasing the size of the interface section that connects the thermal head with the outside. The purpose is to provide a thermal head.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides - a large number of heat generating resistors arranged in rows, and selectively driving each heat generating resistor according to a pattern. a first shift register that outputs serially input image signals in parallel; a latch circuit that temporarily stores the image signals output from the first shift register; a first gate that controls the input of the energization time of the heating resistor; and a first gate that controls the input of the energization time of the heating resistor, and selectively controls the drive element by an image signal output from the latch circuit in accordance with the energization time of the heating resistor controlled by the first gate. an integrated circuit consisting of a second gate that controls energization, the integrated circuit consisting of the second gate being divided into a plurality of pieces every several tens of bits corresponding to each of the heat generating resistors; , having the number of bits equal to the number of integrated circuits.
, and each output terminal of the second shift register is connected to the first gate.

In other words, according to the present invention, the parallel outputs of the shift registers having the number of bits equal to the number of integrated circuits that are driving elements are connected to the ENB input control gate of each driving element, and the block to be recorded is configured as described above. ENB of the drive element corresponding to
By inputting a signal to the shift register so that the input is turned on, recording of one line can be arbitrarily divided and performed.

EXAMPLE Hereinafter, the present invention will be explained based on an example shown in FIGS. 1 and 2.

1 and 2 respectively show the schematic configuration of a driving element for driving a thermal head and a heating resistor according to the present invention. In the figures, 1 is an ENB signal input terminal, 2 is an STE signal input terminal, and 3 is an STE signal input terminal. PiX signal input terminal; 4 is a PcK signal input terminal; 5 is a first shift register that inputs the PiX signal; 6 is a latch circuit that latches the PiX signal stored in the first shift register 6 according to the timing of the STB signal; 7 is a first AND gate that ANDs the PiX signal stored in the latch circuit 6 and the energization time to each heat generating resistor 21; 8 is a driver that drives the heat generating resistor 21 consisting of a large number of switching elements; 9a to 9x are output terminals of the driver 8 connected to one end of the heating resistor 21; 10 is an output terminal from the last pit of the shift register 5; 11.
12 is a power supply terminal, 13 is a recording power supply, 40a to 40x are driving elements for driving the heating resistor 21, and 32 is an input of a selection signal (hereinafter abbreviated as SEL) for the driving elements 4°a to 40X. Signal input terminal, 33 is SEL signal and ENB
A second AND gate for ANDing signals; 41 is a signal input terminal for inputting a signal (hereinafter abbreviated as ESL) for selecting drive elements 40a to 40x corresponding to a block to be recorded; 42 is a second AND gate for inputting an ESL signal to be described later; A signal input terminal 43 inputs a clock signal (hereinafter abbreviated as ECK) to be transferred to the second shift register, and 43 is a second shift register, whose parallel output is connected to the drive elements 40a to 40xLvS.
It is connected to the EL signal input terminal 32.

The operation of the thermal head configured as described above will be explained below.First, an image signal for one line is inputted from the PiX input terminal 3, and a PcK signal inputted from the PcK input terminal 4 drives the drive element 40a. ~40X first shift register 5. At this time, an ESL signal input from the ESL input terminal 41 specifying a block for the first recording is transferred to the second shift register 43 by an ECK signal input from the ECK input terminal 42. Here, for example, the number of integrated circuits of the driving element is 32.
If four-division driving is to be performed for each integrated circuit, the SEL signals input to the SEL input terminals 32 of eight integrated circuits are first turned on. After the transfer of the PiX signal (image signal) is completed, the PiX signal is stored in the latch circuit 6 by the STB signal input from the STB input terminal 2. Furthermore, after the storage is completed, the ENB signal input from the ENB input terminal 1 for controlling the energization time is output, and recording of 1/4 line is first performed. Next, the second shift register 43 has the next 8
from the ESL input terminal 41 so that the SEL signal input to the SEL input terminal 32 of each driving element is turned on.
EC signal input from ECK input terminal 42
Transfer by K signal. Furthermore, after the transfer is complete,
The next 1/4 line is recorded by inputting the ENB signal, and one line is recorded in the same manner.

Note that in the embodiment of the present invention, one line of recording is
The explanation has been given using an example of driving divided into four parts by /4, but the invention is not limited to this. The blocks to be recorded and the number of divisions can be selected arbitrarily, and the selection can be changed for each line.

Effects of the Invention As is clear from the above description, the present invention relates to a heating resistor for one line, a driver for image signals in units of several tens of pits connected to the heating resistor, and an AND gate.

By adopting a configuration that includes a drive element equipped with a latch circuit, a shift register, and a gate that controls the input of energization time, and a shift register that has pits equal to the number of integrated circuits of this drive element, the block to be recorded can be corresponding 1
Since the driving elements are selected and driven by the signals input to the shift register, the blocks and number of divisions for recording one line can be arbitrarily selected, and the interface with the external circuit of the thermal head does not become large. It is effective.

[Brief explanation of the drawing]

FIG. 1 is a schematic circuit diagram of a thermal head according to an embodiment of the present invention, FIG. 2 is a schematic circuit diagram of a driving element thereof, and FIG. 3 is a schematic circuit diagram of a conventional thermal head.
FIG. 4 is a schematic circuit diagram of the driving element. 1...Input terminal for energization time control signal, 2...
...Input terminal for strobe signal, 3...Input terminal for image signal, 4...Input terminal for image signal transfer lock signal, 5...First shift register ,6・
... Latch circuit, 7 ... First AND gate, 8 ... Dojiipa, 9a to 9x ...
・Output terminal, 21...Heating resistor, 32...
...Drive element selection signal input terminal, 33...
Second AND gate, 4oa to 40x... Drive element, 41... Drive element block selection signal input terminal, 42... Clock signal input terminal, 4
3...Second shift register. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
figure

Claims (1)

[Claims] A large number of heating resistors arranged in a row, a driving element that selectively drives each of the heating resistors according to an image signal, and a first shift register that outputs serially inputted image signals in parallel. a latch circuit that temporarily stores the image signal output from the first shift register; and a first gate that controls the input of the energization time to each of the heating resistors.
an integrated circuit including a second gate that selectively controls energization of the driving element according to the energization time to the heating element controlled by the first gate, using an image signal output from the latch circuit; The integrated circuit consisting of the second gate is divided into a plurality of parts each having several tens of bits in correspondence with each of the heat generating resistors, and a second shift register having the number of bits equal to the number of integrated circuits. 1. A thermal head comprising: and each output end of the second shift register is connected to the first gate.