JPS61102862A - Thermal sensitive recording head - Google Patents

Abstract

PURPOSE:To change easily the number of a heating resistance heat driven in every block unit by drawing out strobe lines to respective drivers IC from a substrate on which the drivers IC or a heating resistance are provided so as to connect externally. CONSTITUTION:In a substrute 2, each six terminals of strobe terminals STB are connected in parallel and they are pulled out as strobe terminals STB 1-STB 9. Ground terminals GND are all connected in parallel and pulled out side the substrate 2. Thereby, when strobe signals are successively impressed from the terminals STB 1-STB 9, each six drivers are successively driven. For instance, when each nine drivers are drived six times successively, each nine terminals STB are connected in parallel, and externally the STB are con nected in parallel, and externally the STB 1-STB6 are pulled out. Accordingly, only by changing the substrate 2, the number of heating resistances heat driven every block can be easily changed.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a thermal recording head used in a thermal recording device such as a facsimile machine or a printer, and particularly relates to a thermal recording head used in a thermal recording device such as a facsimile machine or a printer. This invention relates to a heat-sensitive recording head that can be easily changed.

[Background of the invention]

Until now, the known configuration of a thermal recording head is the one shown in "A4 size, 12 pieces/Kaku high-speed thermal head" by Isobaru Takeno (Toshiba Review VOL 38. No. 6 (May 1983)). . According to this, the heating resistor, the driver IC that drives the heating resistor, and the driver IC control signals (latch, clock).

Strobe signals, etc.), power supply, and ground output lines are formed on the same board, which has the advantage of reducing the number of external connection terminals, but the reality is that problems arise when they are fixed.

This is because heat generating resistors are generally driven to generate heat in blocks in order to suppress power supply capacity, but the structure is not such that the number of heat generating resistors within a block can be easily changed. To change the number, it is necessary to change the connection of the strobe signal line to the driver ICK, and therefore the photomask used for manufacturing the board must be changed, which requires a lot of money and time. That is to say.

[Purpose of the invention]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a thermal recording head in which the number of heating resistors that are driven to generate heat in units of blocks can be easily changed.

[Summary of the invention]

For this purpose, the present invention focuses on the fact that in order to be able to change the number of heat-generating resistors that are driven to generate heat in block units, it is sufficient to change the number of driver ICs that are put into a driving state by one strobe signal. The strobe signal lines to each of the driver ICs are connected to the outside from the board on which the driver ICs and heating resistors are provided. When externally connecting strobe signal lines compatible with driver ICs that can be connected externally to a desired block in parallel, the number of heat-generating resistors that are driven to generate heat in each block can be easily changed. It is something that

[Example of invention]

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

FIGS. 1 and 2 respectively show examples of the structure of a thermal recording head and its peripheral circuit according to the present invention, with a recording length of 216 square meters and a recording density of 8 dots/1 m. First, to explain what is shown in FIG. 1, 1728 (=216×8) heating resistors R
"17□8, terminal section vH for supplying power to these
Drivers IC1 to IC54 as ICs are mounted to drive the heating resistors R1 to 17□8 in units of 32@l, and various signals are inputted to the drivers ICI to IC54 from the outside. That is, a data input terminal DI to the shift register in the drivers ICI to IC54, a strobe terminal STB to the drivers ICI to IC54, a ground terminal GND, a clock terminal CLK, a latch terminal LA, and a power supply terminal Vcc are provided. Of these, the clock terminal CLK, latch terminal LA, and power supply terminal Vcc may be provided in common to each driver ICI to IC54 without causing any problems, but rather are preferable in order to reduce the number of input terminals. ing.

However, in the case of the present invention, the strobe terminal 8TB and the ground terminal GND are connected to the drivers ICI to IC5.
4 so that it can be connected externally. This means that if the strobe signal lines are connected fixedly and in parallel within the ceramic substrate 1 and then brought out to the outside, the number of drivers that make up the block is fixed, and therefore, each block generates 9. This is because the number of heat generating resistors to be driven is also fixed. Note that the ground terminal GND will be described later.

Now, the auxiliary flexible substrate 2 having predetermined printed wiring is electrically connected to the ceramic substrate 1 constructed as described above by soldering. As shown in the figure, the strobe terminals STB are connected in parallel at each terminal part in the flexible board 2, each six terminals are connected in parallel, and the strobe terminals STB are drawn out as strobe terminals 5THI to 5TB9. , the ground terminals GND are all connected in parallel and are drawn out to the outside of the flexible substrate 2. The other terminals are simply drawn out to the outside of the 7x7 lexical board 2 through the single 17c7 lexical board 2. Therefore, in the thermal recording head in this example, the serial image signal (17
28 bits/line) uses the clock signal from the clock terminal CLK as a shift pulse to drive the drivers IC1 to IC.
Shifted and transferred in the shift register at 54, 17
At the time when 28 bits have been shifted and transferred, the image signal is latched in the latch in each driver ICI to IC54 by the latch signal from the latch terminal LA, and then if the strobe signal is sequentially applied from the strobe terminals 5TBI to 5TB9, the driver is The heating resistors are sequentially driven in units of 6, ie, in units of 192.

Next, FIG. 2 will be explained. In the one shown in Fig. 1, the heat generating resistors are driven to generate heat 9 times in units of 192, but in order to reduce the heat generating drive time per line, for example, the heat generating resistors are driven in units of 9, that is, the heat generating resistors are driven in units of 9. It is conceivable to sequentially drive the resistors six times in units of 288 resistors. Figure 2 shows the case where drivers are driven in units of nine.As shown in the figure, on the flexible board 2, strobe terminals STB are connected in parallel in units of nine, and external strobe terminals 5TBI to 5TB6 are connected. It is now being extracted as

In other words, if the basic ceramic substrate 1 on which the driver and heating resistor are mounted is connected to the flexible substrate 2 in which the strobe wire is drawn out to the outside, the flexible substrate 2 must be changed. The number of heating resistors that are driven to generate heat in each block can be easily changed by simply changing the number of heating resistors. The reason why the ground terminal GND is also connected to the driver (ceramic board) is that this is because a large current from or to the heating resistor flows through the ground signal line. No. For example, in the case shown in Figure 1, a total of 7.7 A of current flows in the ground line corresponding to the block, and
In the case shown in Fig. 2, a current of 11.5 A flows, but when changing the ground signal width within the flexible board according to the magnitude of the flowing current, it is necessary to change the number of heating resistors that are driven to generate heat at the same time. This makes it possible to easily deal with changes in the system.

〔Effect of the invention〕

As explained above, the present invention provides at least a driver I
Since the strobe signal line compatible with C is drawn out from the thermal recording head mounting board so that it can be connected to the outside, when the strobe line is connected as desired outside the thermal recording head mounting board, the heat generated by the heat generation drive in block units is required. This has the advantage that the number of resistors can be easily changed.

[Brief explanation of the drawing]

FIGS. 1 and 2 are diagrams showing examples of the configuration of a thermal recording head and its peripheral circuits according to the present invention, respectively. l...Ceramic board (thermal recording head mounting board),
R1-R1728・Heating resistor, IC1~IC54・
...Driver +, STB...Strobe terminal, GND
...Ground terminal.

Claims (1)

[Claims] In a thermal recording head in which the maximum required number of heating resistors and driver ICs provided corresponding to a certain number of the resistors are mounted on the same substrate, at least the strobe signal line and ground line corresponding to the driver IC are used for thermal recording. A thermal recording head characterized by a configuration in which it is connected to the outside of a head mounting board and is drawn out from the board.