JPS5856914B2 - Printing device control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has a large number of printing hammers arranged along a printing position, and is designed to improve printing quality in a printing device in which the large number of printing hammers are driven almost simultaneously. The present invention relates to a control device.

In an impact line printer in which a large number of printing hammers are arranged to face a type conveying body such as a type drum or a type belt, or a platen, when the printing hammers of a predetermined number of digits or more are driven, the printing hammers move against the type conveying body or platen. The hammer base to which the printing hammer is attached vibrates due to the reaction of the impact force that collides with the printing hammer, and the distance between the printing hammer and the type carrier or platen, which are then driven once, changes.

Due to this change in distance, the flight time of the printing hammer changes, and the printing location of the printing hammer changes.

As a result, there was a drawback that the characters were irregularly arranged and the print quality deteriorated.

An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to improve printing quality.

For this reason, the present invention is characterized in that when more than a predetermined number of printing hammers are driven, the printing operation is inhibited for a predetermined period of time until the vibration of the hammer base subsides.

The present invention will be explained below with reference to embodiment drawings showing a line blink in which a printing hammer is opposed to a type carrier.

FIG. 1 shows an embodiment of the present invention, in which 1 is a character code buffer that stores a type code on a type carrier (not shown), 2 is a line buffer that stores one line of characters to be printed, and 3 is 1 in character code buffer 1
A comparison circuit scans all the characters in the line buffer 2 for each printed character and compares and matches them. 4 is a Nantes gate that sends comparison information from the comparison circuit 3 at the timing of the timing signal TP1. 5 is a coincidence signal output of the Nantes gate 4. This flip-flop is set by the timing signal TP2, which is generated a predetermined time later than the timing signal TPI.

6 is a shift register provided in the number of all print digits, and a shift pulse S1? The output of the flip-flop 5 is sent sequentially.

Reference numeral 7 denotes a Nant gate connected to the output side of each stage of the shift register 6, and the gate is opened by a print command pulse S2 generated after comparison of all print digits is completed.

Reference numeral 8 denotes a drive circuit connected to the output side of the Nant gate 7, which is composed of a transistor, a solenoid coil, etc., and drives a printing hammer (not shown).

Reference numeral 9 denotes a counter connected to the output side of the Nant gate 4, which counts the number of matching comparison information, that is, the number of printed digits.

10 is a decoder that generates an output when the count value of the counter 9 exceeds a predetermined value, that is, the minimum value of the printing hammer in which the hammer base vibrates; 11 is an AND gate connected to the output side of the decoder 10; Its gate is opened by a pulse CH generated at the start of comparison.

Reference numeral 12 is a monomultiplier triggered by the output of the AND gate 11, and its output is fed back to the input side of the Nandt gate 4 to prevent the Nandt gate 4 from opening for a predetermined period of time.

Note that the counter 9 and the decoder 10 are connected to the AND gate 1.
Cleared by outputting 1.

When a predetermined number or more of matching information is obtained that causes the hammer base to vibrate, and a predetermined number or more of printing hammers are driven almost simultaneously, the count value of the counter 9 that counts the matching information of the Nant gate 4 also exceeds a predetermined value and the decoder 10 Generates output.

As a result, the AND gate 11 opens its gate by the pulse CH used to compare the next character to be printed, the monomulti 12 is triggered, and its output causes the Nante gate 4 and the monomulti 12 to return to a stable state. Since the gate is not opened until then, the printing operation is blocked.

If the output pulse width of the monomulti 12 is made slightly longer than the time required for the hammer base to vibrate and attenuate, the printing operation will resume after the hammer base has completely attenuated and come to a standstill, thereby eliminating the problem caused by the vibration of the hammer base. This prevents the above-mentioned irregular character arrangement.

FIG. 2 shows another embodiment of the present invention, in which the printing operation blocking time is set accurately.

That is, the flip-flop 21 set by the AND gate 11, the Nant gate 22 which takes the AND of the O-side output of the flip-flop 21 and the clock pulse Ci.
, a counter 23 that counts clock pulses CLK sent through a Nant gate 22, and a decoder 24 that generates an output that resets the flip-flop 21 when the count value of the counter 23 reaches a predetermined value. The printing operation blocking time is accurately set by counting the number of CLKs.

As described above, in the present invention, after a predetermined number or more printing hammers have been driven and printed, the printing operation is blocked until a predetermined period of time has elapsed, and then the printing operation is restarted, so that irregular character alignment can be prevented. Print quality can be improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the apparatus of the present invention, and FIG. 2 is a partially omitted block diagram showing another embodiment. In the figure, 1 is a character code buffer, 2 is a line buffer, 3 is a comparison circuit, 4°7.22 is a Nant gate, 5,
21 is a flip-flop, 6 is a shift register, 8 is a printing hammer drive circuit, 9 and 23 are counters, 10.2
4 is a decoder, 11 is an AND gate, and 12 is a monomulti.

Claims (1)

[Claims] 1. In a printing device having a large number of printing hammers arranged along the printing position, a counting means for counting the number of printed digits, and when the count value of the counting means is equal to or greater than a predetermined value, the next printing operation is started after a predetermined period of time has elapsed. and a blocking means for blocking the next printing operation until a predetermined period of time elapses after a predetermined number or more printing hammers are driven almost simultaneously and printing is performed.