JPH091863A - Printing control circuit for serial printer - Google Patents

Abstract

PURPOSE: To make it possible to correct the error of a printing position due to the elongation of a belt by calculating a correction value for correcting the positional change of a print head from the time of oscillating a printing signal to the sticking of ink to a printing sheet, and calculating the time from the time of oscillating the printing signal to arrival of ink at the printing position. CONSTITUTION: A correcting circuit 3 inputs a direction signal 13 for indicating a speed signal 12 from a speed detector 1 and a direction signal 13 for indicating a carrier moving direction from a position detector 2, calculates a correction value for correcting the positional change of a printing head from the time of oscillating the printing signal to the sticking of ink to a printing sheet, and outputs a correction signal 15. A calculator 5 corrects the value of a printing position signal 16 by the signal 15, obtains the difference between the obtained correction signal and the value of the signal 14, and divides the value by the value of the signal 12 to obtain the time from the time of oscillating the printing signal to the arrival of the printing position. When the time coincides with the timer signal 17, a comparator 7 outputs a printing timing signal 19.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print control circuit for a serial printer, and more particularly to a print control circuit for a serial printer which eliminates the influence of the moving speed of a print head.

[0002]

2. Description of the Related Art A conventional serial printer, when performing printing at a target print position on a print sheet, controls the moving speed of a print head (carrier) to be a constant speed and then prints at the target print position. The printing operation is started from the time when the head arrives, and thereafter the printing operation is performed at a constant time interval so that character printing is performed at a constant interval on the printing paper.

[0003]

In the conventional print control system of the serial printer as described above, the print position on the print paper is obtained from the rotation speed of the motor for driving the movement of the print head (carrier). However, it has a drawback that it is difficult to correct an error in the printing position caused by the mechanism such as the extension of the belt that transmits the rotation of the motor to the carrier or the backlash of the transmission gear. . After the printing operation is started, the print position interval on the print paper is determined by the print head drive time interval. Therefore, the print position interval is changed by the fluctuation of the speed of the motor that moves the print head (carrier). It also has the problem of becoming irregular.

[0004]

A print control circuit of a serial printer according to the present invention is provided along a moving carrier having a print head mounted thereon and generates one pulse each time the carrier moves a certain distance. And a linear encoder for transmitting a pulse signal containing information indicating the moving direction of the carrier, and the speed of the print head is detected by inputting the pulse signal from the linear encoder and measuring the time interval of the pulse. A speed detection circuit for detecting the position of the print head by counting the number of pulses by inputting the pulse signal from the linear encoder, and a position detection circuit for detecting information on the moving direction of the carrier. , Before inputting the speed signal from the speed detection circuit and the direction signal from the position detection circuit A correction circuit that outputs a correction signal by calculating a value for correcting a change in the position of the print head from when a print signal is applied to the print head until ink is attached to the print paper, and a comparison circuit from the comparison circuit. A print position generation circuit that inputs a print timing signal and outputs a print position signal indicating a print position of a serial printer at each input timing, a speed signal, a position signal from the position detection circuit, the correction signal, and the print An arithmetic circuit for calculating a time from inputting a position signal to give a print signal to the print head to arriving at a print position; a timer circuit for inputting the position signal to measure an elapsed time; Inputs the operation signal from the operation circuit and the timer signal from the timer circuit, compares them, and outputs the print timing signal. In particular, the value of the print position signal from the print position generation circuit is corrected by the value of the correction signal from the correction circuit, and the corrected value and the position signal from the position detection circuit are provided. The calculation circuit that calculates the time from when the print signal is given to the print head until it arrives at the print position is calculated by finding the difference from the value and dividing the difference by the value of the speed signal from the speed detection circuit. Be prepared.

[0005]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention.

In FIG. 1, a linear encoder 8 is provided along a carrier that carries a print head and moves, and sends out a pulse signal 11 that generates one pulse every time the carrier moves a certain distance. To do. The pulse signal 11 also includes information indicating the moving direction of the carrier. The speed detection circuit 1 receives the pulse signal 11 from the linear encoder 8 and detects the speed of the print head by measuring the time interval of the pulse.
The position detection circuit 2 receives the pulse signal 11 from the linear encoder 8 and detects the position of the carrier, that is, the print head by counting the number of the pulses, and also detects the information regarding the moving direction of the carrier. The correction circuit 3 includes a speed signal 12 from the speed detection circuit 1 and a direction signal 1 from the position detection circuit 2 which indicates the moving direction of the carrier.
3 is input, a value (correction value) for correcting the change in the position of the print head from the time when the print signal is applied to the print head to the time when the ink is attached to the print paper is calculated, and the correction signal 15 is calculated. Output. The print position generation circuit 4
The print timing signal 19 output from the comparison circuit 7 is input, and the print position signal 16 indicating the print position of the serial printer is output at each input timing. The arithmetic circuit 5 is
The value of the print position signal 16 from the print position generation circuit 4 is corrected by the value of the correction signal 15 from the correction circuit 3, and the difference between this correction value and the value of the position signal 14 from the position detection circuit 2 is calculated to obtain the difference. The value is divided by the value of the speed signal 12 from the speed detection circuit 1 to calculate the time from when the print signal is given to the print head until the print position is reached. The timer circuit 6 inputs the position signal 14 from the position detection circuit 2 and measures elapsed time. The comparison circuit 7 includes a calculation signal 18 from the calculation circuit 5 and a timer signal 17 from the timer circuit 6.
Is input, and when they match, the print timing signal 19 is output to the outside and sent to the print position generation circuit 4.

Next, the operation of the print control circuit of the serial printer configured as described above will be described.

The serial printer (printer) first moves the carrier to the left end position to perform so-called carrier homing. After the end of this career homing
The counter of the position detection circuit 2 is reset to initialize the printer.

When the initialization is completed, the printer edits the print data to determine the print direction, determines the print start position and the print interval, and sets those values in the print position generation circuit 4. The print position generation circuit 4 prints the relative print position from the carrier homing position on the basis of the print start position and the print interval at each generation timing of the print timing signal 19 output from the comparison circuit 7. Output as.

Next, the printer moves the carrier in the designated printing direction. Due to this movement of the carrier, the linear encoder 8 sends out a pulse signal 11 which generates one pulse each time it moves a certain distance. The speed detection circuit 1 receives the pulse signal 11 from the linear encoder 8 and detects the speed of the carrier, that is, the print head by measuring the time interval of the pulse. The position detection circuit 2 uses the pulse signal 11 from the linear encoder 8.
When the carrier moves in the left direction, the pulse signal 11 is counted up every 1 pulse, and when the carrier is moved in the right direction, the pulse signal 11 is counted down every 1 pulse, the carrier homing position is changed. The distance is output as the position signal 14. Position detection circuit 2
Also outputs a direction signal 14 from the information indicating the moving direction of the carrier included in the pulse signal 11. The correction circuit 3 receives the speed signal 12 from the speed detection circuit 1 and the direction signal 13 from the position detection circuit 2 and prints a print signal from the print head until ink is attached to the print paper. A value (correction value) for correcting the change in the position of the head is calculated and the correction signal 15 is output.
This correction value is a negative value when the carrier is moved to the right, and a positive value when the carrier is moved to the left. The arithmetic circuit 5 corrects the print position signal 16 from the print position generation circuit 4 with the value of the correction signal 15 from the correction circuit 3, and the difference between this position correction value and the value of the position signal 14 from the position detection circuit 2. (Difference between the print position and the position of the print head) is calculated and the value is used as the speed signal 1 from the speed detection circuit 1.
By dividing by 2, the time from when the print signal is applied to the print head to when it reaches the print position is calculated. The timer circuit 6 receives the position signal 14 from the position detection circuit 2, is reset for each output signal of the position signal 14, and outputs the measured time at that time as a timer signal 17. The comparison circuit 7 inputs a calculation signal 18 indicating the arrival time from the calculation circuit 5 to the print position and a timer signal 17 indicating the time count from the timer circuit 6, and when they match, a print timing signal 19 is output. It is output to the outside and sent to the print position generating circuit 4. The print position generation circuit 4 receives the print timing signal 19
A print position signal 16 indicating the next print position is output.

[0012]

As described above, the print control circuit of the serial printer of the present invention operates from the time when the speed signal from the speed detecting circuit is applied to the print head to the time when the ink is attached to the printing paper. A correction circuit that calculates a correction value to correct the change in the position of the print head, and the value of the print position signal from the print position generation circuit is corrected by the value of the correction signal from the correction circuit. Calculate the difference from the value of the position signal from the circuit and divide that value by the value of the speed signal from the speed detection circuit to determine the time from when the print signal is given to the print head until the print position is reached. An arithmetic circuit for performing arithmetic operation is provided, and in the comparison circuit, an arithmetic signal indicating the arrival time from the arithmetic circuit to the print position is compared with a timer signal indicating the measured time from the timer circuit and they are compared. When it does, by outputting the print timing signal to the outside and sending it to the print position generating circuit to output the next print position signal, the mechanism such as the extension of the belt that transmits the rotation of the motor to the carrier and the backlash of the transmission gear. When a print position error caused by the error occurs, it is possible to correct it.
Further, there is an effect that it is possible to perform accurate printing by correcting the irregularity of the printing position interval due to the fluctuation of the moving speed of the carrier.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

[Explanation of symbols]

 1 speed detection circuit 2 position detection circuit 3 correction circuit 4 print position generation circuit 5 arithmetic circuit 6 timer circuit 7 comparison circuit 8 linear encoder 11 pulse signal 12 speed signal 13 direction signal 14 position signal 15 correction signal 16 print position signal 17 timer signal 18 Calculation signal 19 Print timing signal

Claims (2)

[Claims] 1. A pulse signal which is provided along a carrier on which a print head is mounted and which is provided every time the carrier moves a certain distance to generate a pulse and which contains information indicating a moving direction of the carrier. A linear encoder for sending out, a speed detection circuit for inputting the pulse signal from the linear encoder and measuring the time interval of the pulse to detect the speed of the print head, and the pulse signal from the linear encoder. From a position detection circuit that detects the position of the print head by counting the number of pulses input and detects information about the moving direction of the carrier, a speed signal from the speed detection circuit, and the position detection circuit. Input to the print head and input to the print paper. Correction circuit for calculating a value for correcting a change in the position of the print head until the ink is attached and outputting a correction signal, and a print timing signal from a comparison circuit is input to the serial printer for each input timing. A print position generating circuit for outputting a print position signal indicating the print position of the print head, a position signal from the speed signal and the position detection circuit, the correction signal and the print position signal are input to the print head. A calculation circuit that calculates the time from the application of the signal to the print position, a timer circuit that inputs the position signal and measures the elapsed time, a calculation signal from the calculation circuit, and a timer signal from the timer circuit And a comparison circuit that outputs the print timing signal by comparing them and outputs the print timing signal. Print control circuit. 2. The value of the print position signal from the print position generation circuit is corrected by the value of the correction signal from the correction circuit, and the difference between the corrected value and the value of the position signal from the position detection circuit is calculated to obtain the difference. 2. A calculation circuit for calculating the time from when a print signal is applied to the print head to when it arrives at the print position by dividing the difference by the value of the speed signal from the speed detection circuit. The print control circuit of the described serial printer.