JPS59171673A - Controlling method of thermal recorder - Google Patents

Abstract

PURPOSE:To print with uniform printed density at a part proximate to a boundary of each block, by a method wherein a plurality of recording heads arranged in a rectilinear form are divided into a plurality of blocks, and adjacent ones of the blocks are not continuously supplied with electric currents for heating. CONSTITUTION:The recording heads 102 are provided in 10 blocks, namely, for 560 dots in a rectilinear form, with each block corresponding to 56 bits. A printing operation is conducted for each block as a unit, or a plurality of blocks in such a range that the number of printing dots does not exceeds an allowable total electric current consumption can be simultaneously driven. The block No. (BK0-BK9) is sequentially renewed so that adjacent ones of the blocks are not continuously operated for printing. Namely, the blocks are renewed in the manner of BK0 BK2 BK4 BK6 BK8 BK1 BK3 BK5 BK7 BK9. Accordingly, a temperature difference at a part proximate to the boundary of each block is eliminated as indicated by Tb, and favorable printing can be conducted with uniform printed density.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a thermal recording device, and more particularly, to control of a thermal recording device that performs print recording by selectively energizing heating elements of a recording head disposed on the @ line. Regarding the method.

[Prior art]

Conventionally, a plurality of heat-generating resistors arranged linearly above the recording head are selectively heated with electricity, all of the thermal paper in contact with the heat-sensitive paper develops color, and the heat-sensitive resistor is heated so as to intersect with the recording head. Is this it while sending the paper? There is a thermal recording device that repeatedly forms the entire two-dimensional image. However, driving the recording head in a plurality of blocks is advantageous in terms of current consumption and device cost, and is generally used. In addition, print density unevenness occurred near the boundaries of each block, and in particular, the greater the degree of superheating of the recording head, the more severe the image deterioration was.

[Purpose of the invention]

Is the purpose of the present invention to reduce density unevenness at the boundaries of the blocks? How to control the thermal recording device that has been solved? It is on offer.

[Summary of the invention]

The present invention is a method of energizing and driving a recording head divided into a plurality of blocks, so that adjacent blocks are not heated by energizing continuously.In other words, once heated, the heat generating elements of the block have enough time to dissipate heat. corresponding period,
The next block? The printing side of each block can be printed without applying electricity.

[Embodiments of the invention]

Below are examples of the present invention? Explaining according to the drawing, the first
The figure shows the screen information of CRT display device 1? , an example of a configuration in which the screen information is sent to the thermal recording device 3 through two connection lines and the screen information is printed and recorded? show. That is, the thermal paper 31 (/i) is driven by a pulse motor 32, fed by a roller 33, and colored and recorded by a recording head 34. Then, when recording of a certain size is completed, a cutter 35 is driven to cut it into a certain size. be done.

Is Fig. 2 a control block diagram of the thermal recording device 3? The image information received by the receiving circuit 20 is taken in by the microprocessor 40 every one to several lines, and
Stored in a receive buffer in random access memory (RAM). Further, 100 is a recording head, 101 is a heating resistor, 90 is a block side switching circuit, 70 is a matrix wiring, and 4 types of σ shift registers 71, 72° 7
3.74 is a data output circuit, 60 is a power control circuit for all signal output sides of the switching circuit 80 and data output circuit 70, all of which are microprocessor +
It is controlled by the program execution of the MPU (MPU) 40.

The printing operation is performed by selecting each shift register 71, 72, 73, 74 of the data side switching circuit 70. This is done using the select line 63, and all data is output. The switching circuit 81 (which corresponds to the data string and is driven ON when the print data is "1") operates simultaneously in common to each block;
By the block select signal 62, the block side switching circuit 91? By selectively driving ON, print data is selectively output.

To explain FIGS. 3 and 4, received data 0 to
559, the print data Da is 1 block 55
Is it stored in the reception buffer 42 for each bit?
Indication minute meter l Roblok/Line? The print data in each block is stored separately into odd and even numbers, but this is stored in the previous shift register 71,
This is because it is divided into two parts due to the capacity of 72, 73, and 74. (28bit/SR) Therefore, the recording head 102 is a 56bit pillow and has a linear shape of 560 dont IZJ for 10 blocks?
It shows. That is, the printing operation may be performed for each block, or a plurality of blocks may be driven simultaneously as long as the number of printing dots does not exceed the allowable total consumption 'C flow rate. However, since there are four shift registers, there are shift registers for tolerance and even numbers, so the number of blocks is up to two in this case.

When adjacent blocks are printed consecutively, a synergistic effect of heat generation appears near the boundaries of each block, as in Ta, and the idiot in that area ends up placing 1.
．． The density was uneven. The present invention is based on these adjacent blocks? This is to update blocks A (BKO-BK9) sequentially to prevent continuous printing, that is, update blocks 1BKO-B.
K2-BK4-BK6-BK8-BKI-BK3-BK
5-BK7-BK9. Toki 2nd block Jisho E! JA is determined by counting the number of printed dots in the block using counters 43 and -44 provided at specific positions in the receiving buffer. After counting, the count value of the block position which is increased by +2 is added, and if the result is less than a certain number, the processing when within two blocks is executed. When all blocks are within 2 blocks, BKo, 2-BK4
, 6-BK8-BKI, and 3-BK5.7-BK9. Final block version BK8 and B
In particular, in the case of K9, the comparison/determination process (Program C) is executed to avoid two-block processing.

As mentioned above, is this invention? If implemented, a heat dissipation period equivalent to at least one VC can be obtained between printing adjacent blocks, so T
As shown in b, there is no temperature difference near the boundaries of each block, and it is possible to perform high-quality printing without unevenness.

Is Fig. 5 a flowchart of the above block update process? This is a simple illustration.

After all blocks have been printed, 32 pulse motors are driven to perform 5 kipk lines, and the printing operation is repeated until the next line is printed.

Then, at the start of each printing process V), the timer fE
] ['W50i constant timer starts printing to the head and ends printing by a time-up interrupt to the microprocessor.

Timer control is implemented.

〔Effect of the invention〕

Is the effect of the present invention due to the thermal influence of adjacent blocks? Since it can be made small, extremely good print quality can be obtained.

[Brief explanation of drawings]

1N is a system configuration diagram according to the present invention, FIG. 2 is a control block diagram according to the present invention, FIG. 3 is an explanatory diagram of the reception buffer, FIG. 4 is an explanatory diagram of the Vig recording head and temperature distribution, and FIG.
FIG. 1 is a schematic flowchart of the present invention. 101...Recording head, 62...Block select message 3rd figure also ω figure 5th figure

Claims (1)

[Claims] 1. A recording head consisting of multiple heat generating resistors? In a thermal recording device that selectively energizes the heat generating resistor and performs printing using the generated heat, the recording head portion ? A control method for a thermal recording device characterized by driving the N-drive circuit separately in a plurality of blocks and sequentially driving each block in an apron position.