JPS63280657A - Dot recorder - Google Patents

Abstract

PURPOSE:To print at high speed while maintaining printing quality, by providing delay circuits for recording elements, and simultaneously recording on a recording sheet set on a platen roller by each of the recording elements. CONSTITUTION:Printing data with seven dots in a vertical column as a unit is set into a latch circuit 11, with one dot column as a unit, by a controlling part according to a printing character pattern. The controlling part generates a printing pulse PPO synchronized with an auxiliary scanning timing, and the pulse PPO is inputted to AND gates 31, 37 and to delay circuit 51-53 for delay times T1-T3. The delay times T1-T3 are so set that all of a fourth wire, which is a central wire of a head, third and fifth wires adjacent to the fourth wire, second and sixth wires adjacent thereto and first and seventh wires adjacent thereto reach a printing paper at the same time. With this setting, recording quality on a recording sheet 4 set in a curved state is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a dot recording device for recording characters and the like using dots. More specifically, the present invention relates to a dot recording apparatus, such as a wire tod printer, which has a recording head in which a plurality of dot recording elements are arranged in the circumferential direction of a platen roller, and performs recording by moving this recording head in the axial direction of the platen roller.

[Prior Art] Various types of serial printers, such as inkjet type, thermal type, and wire dot type, have been put into practical use as print output devices for computers and word processors.

Among these, in the wire dot method where the print paper and the print head are not fixed type, the relationship between the tip 2 of the print head 1 and the circumferential surface of the platen roller 3 is not parallel, as shown in Figure 4 at -112. state. That is, a round platen roller 3 is used to wind up the paper, and the printing paper 4 is closely pressed against the round platen. On the other hand, the tip of the wire 5 of the print head 1 is aligned in a vertical direction (paper feeding direction) along the circumferential surface of the platen roller. Therefore, the distance between the print head wire 5 and the paper 4 is such that the center wire is closest to the print paper 4.
It gradually becomes difficult to follow toward the upper and lower end wires.

The above-described print head 1 is moved back and forth 8 times along the guide shaft 6 in a direction perpendicular to the paper surface, that is, in the axial direction of the platen roller 3, that is, in the axial direction of the platen roller 3 and in the width direction of the printing paper 4, by a driving means (not shown). work

Conventionally, the print head 1 described above was driven by a drive circuit shown in FIG. That is, the data of 7 vertical dots according to the print character pattern is stored in the latch circuit 7, and the print pulse p is synchronized with the sub-scanning timing of the print head (print timing in the direction perpendicular to the paper surface in FIG. 3).
-p opens AND gate 8 and further driver 9
1 dot column (1 vertical line) of information via -
Printing is performed by simultaneously driving the wire solenoids 10. On the other hand, since the distance between the printing paper 4 and the tip of the wire 5 is widened from the 4th wire in the center to the 1st wire and the 7th wire, the print head is moved in the sub-scanning direction at high speed. In high-speed printing, for example, when an attempt is made to print the English letter I, the character ■ becomes curved as shown in FIG. 6, resulting in a significant drop in printing quality.

[Objective] The present invention has been made to eliminate the above-mentioned conventional drawbacks, and provides a serial type dot recording device that enables high-speed printing without degrading print quality. The purpose is to

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the drawings.

FIG. 1 shows an embodiment of the present invention. Further, as for the printing mechanism, the example shown in FIG. 4 can be used as is. In FIG. 1, print data in units of seven vertical dots is set in a latch circuit 11 at a single dot column position by a control section (not shown) according to a print character pattern. The control section emits a print pulse PPO synchronized with the sub-scanning timing, and this PPO is input to AND gates 31 and 37. The PPO is T1. Delay circuit 5 for delaying T2 and T3
1 to 33 are input. This T1°T2. The delay time of T3 is the center wire of the head.

The 4th wire, the 3rd wire next to it. The fifth wire, and the second wire next to it. The 6th wire, and the 1st wire next to it. The time is set so that all the seventh wires reach the printing paper at the same time.

The output PPI of the delay circuit 51 is an AND gate 32.3
The output PP2 of the delay circuit 52 is input to the AND gates 33 and 35, and the output PP3 of the delay circuit 53 is input to the AND gate 34. FIG. 2 shows each output PPO to PP3.

The outputs D1 to D7 of the latch circuits are the other inputs to the AND gates 31 to 37.

The outputs H1 to H7 of the AND gates 31 to 37 are input to the head drive circuits 21 to 27, respectively, and energize the wire solenoids 41 to 47 of the print head.
Printed in dot column units. FIG. 3 shows the driving timing of each wire. In the above, PPO is the basic print pulse, PPI is the print pulse delayed by T1 time by the delay circuit 51, PP2 is the print pulse delayed by the delay circuit 52 for 12 hours, and PP3 is the print pulse delayed by the delay circuit 53 by 13 hours. Print pulse, H1~H
7 shows the signal waveform manually input to the solenoid drivers 21 to 27 when all seven dots in the vertical direction are 1.

[Effect] As is clear from the above description, according to the present invention, in a serial type dot recording device that records while moving the recording head at high speed, by providing a delay circuit, each recording element of the recording head However, recording is simultaneously performed on a curved recording sheet, improving recording quality.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a waveform diagram of the delay output, FIG. 3 is a waveform diagram of the wire drive output, and FIG. 4 is a schematic diagram showing the relationship between the printing bed and the platen.
FIG. 5 is a block diagram showing a conventional example, and FIG. 6 is a diagram showing printed character strings in the conventional example. 1-m-print head, 3-m-platen roller, 4-m
-Printing paper, 11-m-Latch circuit, 21-27---
Head driver, 31-37---AND gate, 41-47---Head solenoid, 51-53---delay circuit.

Claims (1)

[Claims] In a dot recording device that performs recording while moving a recording head in which a plurality of recording elements are arranged in a circumferential direction of a platen roller at a distance from the circumferential surface of the platen roller in an axial direction of the platen roller, a delay circuit is provided for the recording elements, A dot recording apparatus characterized in that each of the recording elements simultaneously records on a recording sheet on the platen roller.