JPS6367163A - Printing method by serial thermal printer - Google Patents

Abstract

PURPOSE:To perform normal printing in one process, by a method wherein a plurality of printing element rows are provided to judge whether there is an inferior printing element and, when an inferior printing element is discovered, driving is changed over to the normal printing element row to drive said row. CONSTITUTION:Two printing element rows 2, 11 having the same dot pitch are provided and a switching element 14a changing over the first common wire 13a and the second common wire 13b is provided to a control circuit 14 for driving said printing element rows 2, 11. Before printing is performed by the first printing element row 2, the resistance value of each of the printing elements of the first printing element row 2 is checked by a resistance value judge circuit to check the presence of an inferior printing element. When there is no inferior printing element, printing is performed by the first printing element row 2. When the inferior printing element is discovered, the switching element 14a of the control circuit 14 is changed over to the side of the second common wire 13b. When the resistance value of each of the printing elements of the second printing element row 11 is checked and the resistance value is normal, the second printing element row 11 is driven so as to be delayed or advanced by the time necessary for the movement of a thermal head 1 over the distance between the first and second printing element rows 2, 11 to perform normal printing on a printing area 4.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a printing method using a serial thermal printer, that is, a serial thermal printer in which a plurality of heating elements for printing are arranged in seven rows and each element is driven according to a program. The present invention relates to a printing method using a printer.

[Conventional technology]

A serial thermal printer has a thermal head in which a plurality of heating elements for printing, that is, printing elements are lined up in a vertical line, and the printing elements are controlled to generate heat according to the characters to be printed, and are printed onto thermal recording paper. Printing was performed directly or via a thermal transfer ink ribbon.

In this type of dot printing, in order to print by moving the printing elements arranged in seven vertical rows in parallel, seven of the printing elements
If a piece becomes defective, the corresponding part will not be printed,
/ All lines will be removed.

For example, as shown in FIG. 2, the thermal head (1) has a printing element row -) consisting of a plurality of printing elements (, Za) arranged in seven vertical columns, and among them, there is a defective printing element (
3), the printing area t created by printing in the direction of arrow A
A missing portion (5) of printing occurs in the image (lI).

Figure 3 is Tokukai Sho! 1g-107366. In the figure, (1) is a thermal head, (, 2) is a printing element array, (2a) is each printing element, and (3) is a thermal head. ) is a defective printing element, (3
a) is a complementary printing element that complements the defective printing element (3);
6) is a printed portion supplemented by the complementary printing element (3a).

Next, the operation of this conventional method will be explained.

If the defective printing element (3) causes a missing part of the print (,1), move the printing paper and the thermal head (1) relative to each other during backscanning of the thermal head (1), Correct the position so that the normal head part, that is, the complementary printing element (3a) that complements the printing, faces the missing part (j+). Next, drive only the complementary printing element (3a) to remove the missing part. Complement the printing of the part.

[Problem that the invention seeks to solve]

Since the conventional printing complement dimensions for defective printing elements are configured as described above, the missing dots must be printed in a separate process, that is, backscanning, and therefore the paper must be moved. This tends to cause printing misalignment, resulting in unclear printing.Also, in the case of a thermal transfer method using a thermal ribbon, backscan printing is not possible, so the head that prints the same line again after backscanning is used to complete printing. Since the printing method requires movement, printing time is required to be at least twice as long, and the amount of ink ribbon consumed is also large.

This invention was made in order to solve the above-mentioned problems, and provides a serial thermal printer that can print normally in the / process, has a high printing speed, and can provide clear printing with no printing misalignment. The purpose is to obtain a printing method using

[Means for solving problems]

In the printing method using a serial thermal printer according to the present invention, a plurality of printing element rows are provided, and before printing, it is determined whether there is a defective printing element in the printing element of the printing element row to be used, and if a defective printing element is found. In this step, a printing element column having no defective printing elements is selected from among the other printing element columns, and driving is switched to this normal printing element column to perform normal printing over the entire printing area.

[For production]

According to the printing method of the present invention, it is checked and determined whether or not the printing element array to be driven has a defective printing element, and if it is normal, the printing element array is driven to perform printing, and if the printing element array to be driven is defective, the printing element array is driven and printed. If it is determined that there is a defective printing element, a normal printing element string that does not include the defective printing element is selected from among the other printing element strings, and the drive is switched from the previous printing element string containing the defective printing element to the succeeding normal printing element string. It switches to the printing element row, drives it, and prints.

〔Example〕

The present invention will be explained below based on the drawings showing the outline of one embodiment thereof.

FIG. 1 shows a printing method of a thermal printer according to the present invention, in which two rows of printing elements having the same dot pitch are provided.

Symbol (2) indicates seven printing element columns, for example, the first printing element column, (//) indicates another printing element column, for example, the C-th printing element column, and (,7) indicates the first printing element column ( , 2) is a defective printing element that occurs on the top.

In addition, the symbol (80) is an electric line that conducts electricity to each printing element in each printing element row (, 2), (/J), and (/3a) is an electric path that is energized to each printing element in the first printing element row (C). The first common line (/, yb), which is a return path for electric power, is a common line (/, yb) that is a return path for electric power applied to each printing element of the U-th printing element column (//).

In addition, the symbol (C) is a control circuit that controls whether to drive the first printing element row (2) or the U-th printing element row (//), and (/) is the control circuit described above. (It is within C 0 and the 7th common line (/3a) and the 7th common line (/3
b) It is a switching element that switches between.

Next, the operation of this embodiment will be explained.

Before starting printing with the first printing element row (2), the resistance value of each printing element in the first printing element row (2) is checked by a resistance value judgment circuit (not shown) to see if there is a defective printing element. Check. If no defective printing element is found, printing is performed using only the first printing element row.

On the other hand, if a defective printing element (,?) is found, the control circuit (c0) switches the switching element (/y a,
) to the U-th common line (i, yb) side and check the resistance value of each printing element in the second printing element row (//) in the same way as in the case of the seventh printing element row (, 2). do.

What if the resistance value of each printing element in the No. 1 printing resistor row (//) is normal? if, the distance between the i-th J'ff-element row (2) and the C-th printing element row (//) is delayed or advanced by the time it takes the thermal head (1) to move (depending on the direction of movement of the thermal head). , because it is necessary for the first printing element array to print at the position where it should originally print) to perform printing and normally print in the printing area.

In the above embodiment, the case where there is one printing element row has been described, but even if there are three or more rows, the same effect can be achieved and printing reliability can be further improved.

Further, in this embodiment, the control circuit (C) is provided outside the thermal head (1), but it may be mounted inside the thermal head (1).

〔Effect of the invention〕

As described above, according to the present invention, a plurality of printing element rows,
If there is a defective printing element in a printing element row that is to be juxtaposed and driven, a normal printing element row is selected from among the other printing element rows and switched to drive, so a separate process is required during pack scanning. The present invention provides a printing method for a serial thermal printer that allows normal printing to be performed in the /process without the need for printing, and therefore provides clear printing with no printing deviation, and also improves printing speed. It has the effect of reducing

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a printing method according to an embodiment of the present invention;
FIG. 2 is an explanatory diagram illustrating a state in which missing print occurs due to a defective printing element in a conventional apparatus, and FIG. 3 is an explanatory diagram illustrating a conventional complementary printing method. (1) - Malfunctioning thermal head, -)... 7 printing element rows (first printing element row), (,7)... Defective printing element,
(ri)...Normal printing area, (//)...Other printing element rows (Cth printing element row), (/, 2)...Electric circuits that supply electricity to each printing element, (/, 7a)...・7th common line, (/3b)
・・No. C common line, (c・φ・control circuit, (/4'a)・
・Switching element. In each figure, the same reference numerals indicate the same or corresponding parts. -〉A Rhinoceros 3

Claims (1)

[Claims] In a printing method using a serial thermal printer that performs dot printing using a printing element row in which a plurality of printing elements are arranged, a plurality of printing element rows are provided and a defect occurs in one of the printing elements in one printing element row. A printing method using a serial thermal printer characterized in that when dot printing is missing, printing is performed by switching to another normal printing element array without printing using this one printing element array.