JPS625871A - Determination of printing position in printer - Google Patents

Abstract

PURPOSE:To prevent an unintentional shift in printing from occurring, by a method wherein an output from a sensor is detected according to a comparison result from a comparing circuit for comparing an output from a time counting circuit with the content of a memory circuit, and a printing position is corrected. CONSTITUTION:The time counting circuit 9 for measuring the period of time from a timing pulse of an encoder output 18 to a change in the output of the sensor 4, the memory circuit 10 for storing time, the comparing circuit 11 for comparing the output of the circuit 9 with the content of the circuit 10, and a correcting circuit for correcting the printing position by detecting a shift of the sensor 4 according to the comparison result from the circuit 11 are provided. Accordingly, an unintentional shift of the first character printing position in each line can be prevented from occurring, and printing position in each line can be prevented from occurring, and printing can be constantly started at the correct position.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is a first method for a unidirectional printing serial printer.
This invention relates to a method for determining the printing position of characters.

[Conventional technology]

The conventional technique will be explained with reference to FIG. The drawing is a perspective view of the main parts of the printer, and in the figure, 1 is the print head, 2
3 is a printer frame that supports this carriage 2, etc.; 4 is a printer frame that supports the print head 1;
6 is a first character printing position detection sensor that detects that is at the first character printing position, and 6 is a print timing generation encoder that generates print timing in synchronization with the position of the carriage.

FIG. 7 is a timing chart for determining the first character printing timing, where 7 is the output of the detection sensor 4, and 8 is the output of the encoder 6.

The operation of the above configuration will be explained below.

First, in FIG. 2, the carriage 2 is positioned on the left, at the left end, and is moved rightward from that position. When the detection sensor 4 detects the first character printing position at the timing (4) in FIG. 7, the printing position of each line is determined by using the printing timing (B) immediately after that by the encoder 6 output as the first character printing timing.

[Problem that the invention seeks to solve]

According to the above configuration, for example, when printing a vertical line at the first character position in each line, if dust or the like is attached to the detection sensor 4,
The heat expands and contracts the flexible plate 5, and furthermore, the printer frame 3 expands and contracts due to the heat, and the detection sensor 4 moves, changing the detection timing of the first position of the detection sensor 4 and the encoder 6. The relative relationship of the output pulses may shift to the position (C) in Figure 7, and the printing timing of the first character may be (2), resulting in a shift of one encoder output from the previous line, resulting in printing As a result, there is a problem in that printing misalignment occurs as shown in Figure 8 (@).

[Means for solving problems]

The present invention provides a clock circuit that measures the time from a timing pulse of an encoder output to a change in sensor output, a memory circuit that stores the time, a comparison circuit that compares the clock circuit and the memory circuit, and a comparison circuit that compares the comparison circuit. It is characterized by comprising a correction circuit that detects the deviation of the detection sensor based on the result and corrects the print position.

[For production]

According to the above circuit, by correcting the printing position using the sensor that detects the deviation in the position of the first character, the first
You can adjust the Bunsei egg position.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of the circuit. In the figure, 4 is a detection sensor, 6 is an encoder, 9 is a timing circuit that measures the time from the encoder output pulse to the sensor output change, and 10
1 is a memory circuit that stores the output of the clock circuit 9; 11 is a comparison circuit; and a correction request signal 1 that turns ON when the difference between the output of the clock circuit 9 and the contents of the memory circuit 10 exceeds a certain value.
If the output of the clock circuit 9 and the content of the storage circuit 10 are larger than the output of the clock circuit 9, a correction direction signal 13 is output which instructs the plus direction, and vice versa.

14 is a timing generation circuit that generates the first character part timing signal; 6D, when the correction request signal 12 is turned off, the first character part timing is generated by the second encoder output pulse following a change in the sensor output; , correction request signal 12
is ON, if the correction direction signal 13 is in the positive direction, the third encoder output pulse following the sensor output change, and if it is in the negative direction, the first encoder output pulse is the first encoder output pulse. Generate a signal.

15 is a print control circuit that generates a head drive signal in synchronization with the encoder output after the first Bunsei Oji timing occurs;
16 is a head drive circuit, and 17 is a print head.

Correction of the print position by the above circuit will be explained using a timing chart.

Figure 3 is a timing chart when printing the first line.
17 is the output of the detection sensor 4, 18 is the output of the encoder 6, 12 is a correction request signal, and 19 is the timing generation circuit 14.
The output is the 1st literature timing command. In the case of this timing chart, since the correction request signal 12 is OFF, the first Bunsei egg timing command 19 changes at the timing of the second pulse of the encoder output 18 following the change in the sensor output 17, and the first Bunsei egg timing command 19 changes. The characters start.

The memory circuit 10 stores the time T1 from the pulse of the encoder output 18 to the change in the sensor output 17.

Next, a case will be described in which correction is performed in which the change timing of the sensor output is shifted.

Figure 4 is a timing chart when the sensor output deviates in the next line printed based on the timing relationship shown in Figure 3 above, 17 is the sensor output, 18 is the encoder output, 12.1
3 is the output of the comparison circuit 11, which is a correction request signal and a correction direction signal, respectively. 19 is the output of the timing generation circuit 14, which is the first signal.
This is the literature timing directive.

At the start of printing the line shown in FIG. 4, the contents of the memory circuit 10 are T1 shown in FIG. 3, and the output of the timing circuit 9 is T1 shown in FIG.
2 (j), and since the difference between T2 and T1 is large, the correction request signal 12 is ONI T2 < T I, so the correction direction signal 13 is in the negative direction.

In response to the correction request signal 12, the timing generation circuit 14 generates the first character part timing command 19 in synchronization with the pulse of the first encoder output 18 following the change in the sensor output 17 since the correction direction signal 13 is in the negative direction. The print control circuit 15 starts outputting a print command.

The case where the detection sensor 4 is shifted in the opposite direction and the correction is performed will be explained with reference to FIGS. 5 and 6.

17 is an output of the detection sensor 4, 18 is an output of the encoder 6, 12 is a correction request signal, 13 is a correction direction signal, and 19 is a first Bunsei-egg timing command.

If the next line printed with the timing relationship shown in Figure 5 has the timing relationship shown in Figure 6, the contents of the memory circuit 10 will be T5 shown in Figure 5, and the output of the timing circuit 9 will be shown in Figure 6. T
It is I.

Since the difference between T4 and T3 is large and Tq>T5, the correction request signal 12 is turned on and the correction direction signal 13 is in the positive direction. Therefore, the first character timing command 19 is output and corrected in synchronization with the pulse of the third encoder output 18 following the change in the sensor output 17.

〔Effect of the invention〕

According to the present invention described in detail above, there is provided a clock circuit that measures the time from the timing pulse of the encoder output to a change in the sensor output, a memory circuit that stores the time, and a comparison circuit that compares the clock circuit and the memory circuit. By providing a correction circuit that detects the deviation of the detection sensor based on the comparison result of this comparison circuit and corrects the printing position, it is possible to eliminate the deviation of the first character weight position of each line and start printing from the correct position. It has the effect that it can.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a perspective view of a printer according to the present invention, Fig. 3 is a timing chart when printing the first line, and Fig. 4 is corrected for the next line. Fig. 5 is a timing chart when the correction is performed in the opposite direction to Fig. 3. Fig. 6 is a timing chart when correction is made in the next line. Fig. 7 is an explanatory diagram of the conventional example. , FIG. 8 is an explanatory diagram showing an example of printing misalignment. 4...Detection sensor 6...Encoder 9...Clock circuit 10...Memory circuit 11...Comparison circuit 1
2... Correction request signal 13... Correction direction signal 14
...Timing generation circuit 15...Printing control circuit
1T...Print head

Claims (1)

[Scope of Claims] 1. In a printer that performs unidirectional printing, a clock circuit that measures the time from the encoder output for print position generation to the output of the first character position detection sensor; and a memory circuit that stores the time; It is equipped with a comparison circuit that compares the output of the clock circuit and the contents of the memory circuit, and a correction circuit that corrects the print timing according to the comparison result of this comparison circuit, and detects the above detection sensor output based on the result of the comparison circuit and adjusts the print position. A method for determining a print position in a printer, characterized by correcting.