JPH01184160A - Thermal head - Google Patents

Abstract

PURPOSE:To obtain an image having no difference in level, by providing a difference in level to heat generating resistors at every blocks in the direction vertical to the arrangement direction of the heat generating resistors. CONSTITUTION:The image receiving paper 5 of a printer is successively sent in the direction shown by an arrow A. A this time when the resolving power of each of the heat generating resistors of a thermal head 4 is P dot/mm, one line becomes 1/P and, when the thermal head is divided into four blocks, a distance B becomes 1/4P. A drawing shows that the printer prints a block 6D during the printing of one line but, since a difference in level of B' same to B in a distance is provided to the resistors at every blocks 6A-6D, a printing part 5A is printed by the block 6A and a printing parts 5B... are printed by the blocks 6B.... Therefore, no difference in level is generated on the image receiving paper 5. Since the distance B is extremely smaller than the distance of the image receiving paper 5 in the lateral direction thereof, it can not almost visually confirmed that printed matter becomes an oblique straight line. As mentioned above, by providing a proper distance between the blocks of the heat generating resistors of the thermal head 4, an image having ho difference in level is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a thermal head that performs printing by applying heat.

2. Description of the Related Art In recent years, printers have become faster and have higher image quality. An example of a printer using the above-described conventional thermal head will be described below with reference to the drawings. In Figures 4a and b, 7 is receiving paper, 8 is 4 equal blocks 8
Heat generating resistors a to 8d are arranged in a row, 9 is a thermal head, and 10 is a platen roller. The operations 21 and -7 of the thermal transfer printer configured as above will be described below.

First, when printing on the image receiving paper 7, printing is performed in four blocks due to problems such as power supply capacity.

At this time, paper feeding is stopped during printing of a certain block 8a, and paper feeding is performed immediately before printing of the next block 8b. The following printing is performed sequentially.

Problems to be Solved by the Invention In the case of FIG. 4, when printing is performed from the right block 8a among the four equal blocks 8a to 8d, the paper is fed by a layer corresponding to the feed amount of one line, and then the next block is printed. Print 8b. However, in the above configuration, the printed image has a step difference in the printed portions 7a to 7d corresponding to the blocks 8a to 8d, as shown in FIG. This step has the problem of creating a step in one line and deteriorating the image quality.

In view of the above-mentioned problems, the present invention provides a thermal head that prevents deterioration in image quality due to the occurrence of steps between blocks.

Means for Solving the Problems In order to solve the above problems, the thermal three-page head of the present invention has a structure in which a step is provided for each block having a plurality of heating resistors.

Effect of the Invention With the above-described configuration, the present invention eliminates the problem that a step occurs in each block by shifting the position of the thermal head resistor in each block in advance by a distance corresponding to the amount of movement of the image receiving paper. There will be no.

EXAMPLE Hereinafter, a thermal head according to an example of the present invention will be explained with reference to the drawings. FIG. 1 shows a resistor of a thermal head in an embodiment of the present invention. In FIG. 1, reference numerals 1a to 1d are heating resistors having a step difference for each block, 2 is an alumina substrate, and 3 is a thermal head base. The operation of the thermal head constructed as described above will be explained with reference to FIGS. 1 and 2.

First, FIG. 2 shows the paper feeding movement of the printer and the positional relationship of the thermal head heating resistor, where 4 is the thermal head, 5 is the image receiving paper, and eA.

eB, ec, and eD are each under the applied unit block. In FIG. 2, the receiving paper 5 of the printer is sequentially fed in the direction of arrow A. In FIG. At this time, in general, if the resolution of the heating resistor of the thermal head 4 is Pdot/1ran, one line is 1/Pnm, and as shown in Fig. 2, one line is 1/Pnm.
If it is divided into blocks, the distance B becomes 1/4P. Second
In the figure, the printer prints 6D blocks in one line printing, but since each block 6A to 6D has a step B' at the same distance as B on the resistor, the block The printed portion 6A is printed on block 6A, and the printed portion 5B is printed on block 6B, respectively. Therefore, no level difference occurs on the image receiving paper 5. Moreover, the distance B is also very small compared to the distance in the width direction of the image receiving paper 5 (
For example, if the thermal head 4 is 8 dot/gz, B = 0.03 m, and if the receiving paper 6 is A4, B = 21 m)
Therefore, it is almost impossible to visually recognize that the printed matter becomes a diagonal straight line.

As described above, by providing an appropriate distance between the blocks of the heating resistor 1 of the thermal head 4, an image with no steps can be obtained by 6 pages.

In the example of Fig. 1, the distance B' is 1/4P, but
As the number of blocks changes, the distance B
′ can also be changed. Further, as shown in FIG. 3, the heating element shape 1 shown in FIG. 1 may be arranged such that the position of the resistor is perpendicular to the printing direction to provide a step between the blocks.

Effects of the Invention As described above, the present invention provides a thermal head having a block having a plurality of heat generating resistors and an element for driving these heat generating resistors.
By providing a step in a direction perpendicular to the direction in which the heating resistors are arranged, an image without a step can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a diagram of the resistor of the thermal head in the embodiment of the present invention, Fig. 2 is a diagram showing the paper feeding movement of the printer and the positional relationship of the thermal head heating resistor, and Fig. 3 is the diagram of the resistor of the thermal head in the embodiment of the present invention. FIG. 4 is a diagram showing an example of a printer using a conventional thermal head. 1a-1d...Block, 2...Alumina substrate, 3...Thermal spatula)” Hess. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 2
Figure 3 Figure 4

Claims (1)

[Claims] A thermal head that has a step corresponding to the feed of the image receiving paper in each block in which a plurality of heating resistors are arranged in a line.