JPH03297670A - Printing method in perfect printing dot matrix printer - Google Patents

Abstract

PURPOSE:To print on both sides of a printing paper in a short time by arranging the direction of a printing line of 1st and 2nd heads with respect to a printing paper to be integral multiples of a minimum paper feed pitch and deviating counts of printing positions of the 1st and 2nd heads by a distance corresponding to a time difference between the 1st and 2nd head drive timings in printing 1 line. CONSTITUTION:Arrangements of print elements of 1st and 2nd heads 1 and 2 are made to be the same, and arrangements of the direction of printing line of the 1st and 2nd heads with respect to a printing paper is made to be integral multiples of A minimum paper feed pitch. At a head print timing t1, a 1 pin of the 1st head 1 is selected to print on the top surface of the printing paper by a driving current i1. At a head print timing t2, 1, 2 pins of the 2nd head are selected to print on the back surface of the printing paper by the driving current. A time difference t is previously made between the print timings t1 and t2 so as to regulate for preventing a power load from increasing due to an overlap of the driving currents at simultaneous printing times on the top and back surfaces.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is characterized in that a print head consisting of a print element such as an impact wire pin, an inkjet nozzle, or a heating element is selectively driven by a printing command, and a character or bit image is printed. This invention relates to a printing control method for a double-sided printing dot matrix printer, which has a first printing mechanism part and a second printing mechanism part with a printing paper in between, and is capable of printing on both sides of the printing paper.

[Conventional technology]

Among printers that print characters or bit images in a dot matrix, serial type printers that use a print head consisting of printing elements such as impact wire pins, inkjet nozzles, or heating elements are widely used because of their excellent cost performance. It is widespread. Printing by those printers is
When printing is performed on both sides of the printing paper, the printing paper that has been printed on one side is fed again to the printer and printing is performed on the other side.

There were also problems.

SUMMARY OF THE INVENTION The present invention is intended to solve these problems, and its purpose is to provide an inexpensive double-sided printing dot matrix printer that can simultaneously print on both sides of printing paper in a short period of time.

[Problem to be solved by the invention]

When printing on both sides of printing paper using one head as in conventional printers, there is a problem that the printing paper needs to be manipulated and the printing time becomes long.

In addition, for double-sided printing, two printing mechanisms are installed on the front and back sides of the printing paper, and by adjusting the printing timing of the two heads, the printing position can be controlled in the same way as for single-sided printing with the same power capacity as before. There are other problems such as the print start position being different for the left and right edges of the front and back sides of the printer, and depending on the arrangement of the two heads in the print line direction, it is not possible to secure the print line pitch on the front and back sides by feeding the paper. ] The printing method of the double-sided printing dot matrix printer of the present invention includes a first printing mechanism section and a second printing mechanism section with a recording sheet in between, and a double-sided printing dot matrix printer that prints characters or bit images. The arrangement of the printing elements of the first head of the printing mechanism section and the second head of the second printing mechanism section is the same, and the arrangement of the first head and the second head in the printing line direction with respect to the printing paper is an integral multiple of the minimum paper feed pitch. It is characterized in that the counting of the printing positions of the first head and the second head is shifted by a distance corresponding to the time difference between the first head drive timing and the second head drive timing in one line printing.

[Effect]

According to the printing control method for a double-sided printing dot matrix printer of the present invention, since the first head and the second head are provided with the printing paper in between, it is possible to simultaneously print on both sides of the printing paper in a short time. Furthermore, since the printing position of one printing line on the front and back sides of the printing paper is the same on the paper surface, it is possible to perform double-sided printing with a uniform printing line pitch and high printing quality.

〔Example〕

Hereinafter, the present invention will be explained according to one embodiment.

FIG. 1 is a schematic diagram of a printing mechanism of a double-sided printing printer using an impact dot head as a printing element, in which (a) is a side view and (b) is a plan view. In the figure, 1 is the first head, 2
is a second head, which prints on the front and back sides of the printing paper, respectively. The printing paper 8 is fed along the paper guide plate 7 in the direction shown in the figure. In this embodiment, rollers are used to feed the paper, but other means such as a tractor may also be used. 5
．． Reference numeral 6 denotes a paper feed roller, which is driven by a single paper feed motor that is controlled by a print line feed pitch based on print data on the front or back side. Therefore, 1 on the front or back side
The paper feed at the end of printing of a print line is calculated according to the smaller of the cumulative paper feed amount for the front side n1 * p and the paper feed for the back side n2 * p, assuming that the minimum feed pitch of the paper feed motor is p. needs to be done. Here nl and n2 are integer values. The first and second two heads are the first
As shown in the figure, they are placed ΔL apart, and ΔL=np
(n is an integer value), so by feeding the paper according to the cumulative paper feeding pitch on the front and back sides, the printing line pitch can be made uniform. In FIG. 1(b), reference numeral 9 denotes a first Herad carriage motor, and numeral 13 denotes a second Herad carriage motor, which are driven in synchronization with the printing timing of each head.

FIG. 3 shows front side print data and back side print data for explaining the embodiment. In FIG. 3, black circles indicate the set printing times Tl, T2. It represents the driving of each printing pin in ..., and when there is no black circle, the printing pin is not driven. The case of printing the print data shown in FIG. 3 will be explained using the print timing signal and drive current waveform shown in FIG. 2. At head print timing t1, pin 1 of the first head is selected and printing is performed on the surface of the printing paper using the drive current 11.

Similarly, at the next head print timing t2, the second
Bin 1.2 of the head is selected and printing is performed on the back side of the printing paper using the drive current. Here, there is a time difference of Δt between printing timings t1 and t2, and control is performed so that the driving currents at the same printing timing on the front and back sides do not overlap and the power supply load does not become large. Therefore, if the printing positions on the front and back sides are counted using the same scale, there will be a difference in printing position of △d between the printing start position d1 from the left edge of the printing paper printed on the front side and the printing start position d2 from the right edge of the printing paper printed on the back side. ing. In order to eliminate this difference, the control means for the first printing mechanism and the second printing mechanism are provided with scales for counting printing positions whose absolute positions are shifted by Δd, thereby controlling the printing positions on both sides. The printing position on the back side of the paper is the same.

〔Effect of the invention〕

As described above, according to the printing control method for a double-sided printing dot matrix printer of the present invention, the first
Since the head and the second head are provided, it is possible to simultaneously print on both sides of the printing paper in a short time. Furthermore, the printing position of one printing line on the front and back sides of the printing paper becomes the same on the paper surface, making it possible to perform double-sided printing with high print quality and uniform printing line pitch.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the printing mechanism of the double-sided printing dot matrix printer of the present invention. FIG. 2 is an explanatory diagram of print timing signals. FIG. 3 is an explanatory diagram of print data on the front and back sides. 1: 1st head, 2: 2nd head, 3.4:
Platen, 5.62 Paper feed roller 7: Paper guide,
8: Printing paper, 9: First head carriage motor 13: Second head carriage motor 11.15:
Drive pulley 12.16: Driven pulley 10.14: Drive belt, (C1)

Claims (1)

[Claims] In a double-sided printing dot matrix printer that includes a first printing mechanism section and a second printing mechanism section with a recording sheet in between, and prints characters, bit images, etc., the first head of the first printing mechanism section and The arrangement of the printing elements of the second head of the second printing mechanism section is the same, the arrangement of the first head and the second head in the printing line direction with respect to the printing paper is an integral multiple of the minimum paper feed pitch, and the first A printing method for a double-sided printing dot matrix printer, characterized in that the counting of printing positions of the first head and the second head is shifted by a distance corresponding to the time difference between the head drive timing and the second head drive timing.