JPS6145545B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper feed fine adjustment device that can finely adjust the print position in a printing device such as a line printer.

Fine adjustment of the print position in conventional printing devices is
This was done by an operator using a manual knob 9 shown in FIG. The operator (1) performs a test print. (2)
The test print is stopped, and the manual knob 9 is used to adjust the printing paper 1 and the printing position where the type conveyor 4 travels appropriately based on the printing results.
I was doing this operation. However, due to the distance between the printing position and the tractor 2, the printing paper 1 becomes slack.
Due to the amount of slack, it was difficult to make accurate adjustments at once. Therefore, the operations (1) and (2) above had to be repeated, resulting in poor operability.

An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to simplify the operations required for fine adjustment of the printing position.

In the present invention, a switch for finely adjusting the print position is provided, and when this switch is operated during test printing, the paper is fed by (N+l/M) or (N-l/M) lines.

FIG. 1 is a diagram showing a paper feeding mechanism section. In the figure, printing paper 1 is loaded on a tractor 2,
The tractor 2 is directly connected to the tractor shaft 3, and when the tractor shaft 3 rotates, the printing paper 1
is sent by tractor 2. There is a printing position below the tractor 2, and printing is performed at this printing position. When the manual knob 9 is not pressed, the tractor gear 10 and the tractor shaft 3 are directly connected, and when the paper feed motor 5 rotates, torque is transmitted to the tractor gear 10 via the pinion 6 and the intermediate gear 7, and the printing paper 1 will be sent. When the manual knob 9 is pushed and rotated, the clutch 8 operates, the tractor gear 10 is separated from the tractor shaft 3, and the manual knob 9 is connected to the tractor shaft 3.
The printing paper 1 is sent directly. Therefore, it is possible to finely adjust the stop position of the printing paper 1 using the manual knob 9.

FIGS. 2 and 3 are diagrams showing printing results when the fine adjustment of the present invention is performed. FIG. 2 shows how to correct the position of characters in the first test print when they are below the marking line of the printing paper 1. In this case, by repeating the line feed of (4-1/8) lines twice, the optimum facing relationship between the characters and the ruler lines can be obtained.
FIG. 3 shows the position correction when the position of the character in the first test print is above the marking line of the printing paper 1. In this case, change the line break of (4+1/8) lines to 2
By repeating this process several times, the optimal facing relationship between the characters and the ruler lines can be obtained.

The present invention will be described below with reference to FIG. 4 showing an embodiment of the present invention apparatus that realizes the printing results shown in FIGS. 2 and 3, and FIG. 5 showing a time chart for explaining the operation of FIG. 4. Explain. In the following description, the paper feed motor 5 is assumed to be a stepping motor that feeds one line of printing paper in eight steps.

In Figure 4, the power supply reset signal when the power is turned on
M-ary up-down counter 14 by RESET,
It is assumed that flip-flop 16 and D-type flip-flops 20 and 26 have been reset and the circuit is in its initial state. In the case of a regular line feed, the paper feed controller 11 outputs a signal FEED with a logic value of 0 indicating that it is a paper feed cycle, and a drive pulse STEP PULSE that drives the paper feed motor 5 is applied to the motor drive circuit 12. The paper feed motor 5 starts rotating. The pulse STEP PULSE is passed through an OR gate 13 to an octal up/down counter 14.
Added to the UP input end. When the octal up-down counter 14 counts four of these pulses STEP PULSE, it generates an output 4COUNT. During normal printing, the signal INH STRB, which prohibits the signal LINE STRB from being generated, is not generated, so the output 4COUNT is 1 through the AND gate 15.
LINE signal that indicates that a line is in the middle of a line break
It is added to the paper feed controller 11 as STRB. The paper feed controller 11 receives a signal
When receiving LINE STRB, further drive pulse STEP
Issue four PULSEs to end a line feed.

Next, a sequence for finely adjusting the print position during test printing will be described. Assume that the up-down switch 33 is turned to the UP side while the paper is being fed for test printing because the printing position is below the marking line. At this time, since test printing is in progress, a signal TEST PRINT with a logic value of 0 is output, which is a signal that prohibits input to the up-down switch 33.
Since INH SW is not output, the output of OR gate 28 sets D flip-flop 20. The output of OR gate 28 further triggers one shot 19 via NAND gate 29. The output of the one shot 19 is connected to the signal INH via the delay circuit 18.
It is set to SW, and there is a single up/down switch 3.
3 is operated, the next operation of the up-down switch 33 becomes invalid during the pulse width of the one shot 19.

After the D flip-flop 20 is set, the signal FEED goes to logic 1 when the paper feed cycle is completed.
The output of the AND gate 21 becomes the signal UP PULSE via a pulse generator 22 such as a one-shot or differentiating circuit. The signal UP PULSE is applied to the UP input terminal of the octal up-down counter 14 through the OR gate 13, and the octal up-down counter 14 counts up by one. Signal UP
PULSE is also applied to the OR gate 23 to signal UP/DOWN indicating that UP or DOWN has been set.
It becomes DOWN SET. The signal UP/DOWN SET is applied via delay circuit 27 to the six clock input terminals of D flip-flops 20 and 26 to reset them. signal
UP/DOWN SET also clears the quaternary counter 17 and sets the flip-flop 16. As a result, the signal INH STRB is output and the AND gate 15 is prohibited from opening. In other words, the output of the signal LINE STRB is prohibited. When the next paper feed for test printing starts, the drive pulse STEP PULSE is sent from the paper feed controller 11.
is output and the octal up/down counter 14 counts up. When this count value reaches 4, an output 4COUNT is output and counted by the quaternary counter 17. When the drive pulse STEP PULSE continues to be generated and three outputs 4COUNT are output, the output 3COUNT is output from the quaternary counter 17 and the flip-flop 16 is reset. This will cause the signal INH
STRB becomes a logical value 1, and the fourth output 4COUNT passes through the AND gate 15 and becomes a signal LINE STRB, which is input to the paper feed controller 11. The paper feed controller 11 further generates four driving pulses.
Issue STEP PULSE to end driving of motor 5 and end paper feeding. As a result, the paper is fed by (4-1/8) lines. If the printing position is higher than the marked line, turn the up-down switch 33.
By tilting it to the DOWN side, paper is fed by (4+1/8) lines.

In the above embodiment, 4
The reason for feeding line by line is to make it easier to see the print result after adjusting the print position.This number of lines can be set arbitrarily. If you send only a few copies, you will be able to see the test print results immediately. In addition, when the up-down switch 33 is operated, one pulse is added to the UP input terminal or the DOWN input terminal of the M-ary up-down counter 14 and adjusted by ±1/8 rows. It is also possible to apply two or three pulses to the input terminal to adjust by ±2/8 lines or ±3/8 lines.

As described above, according to the present invention, it is possible to easily finely adjust the printing position by simply operating a switch, and the finely adjusted printing results can be viewed separately for each adjustment, which facilitates the operation.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the paper feed mechanism, FIGS. 2 and 3 are front views showing the printing results when finely adjusted by the device of the present invention, and FIG. 4 is an implementation of the device of the present invention. A block diagram showing an example, and FIG. 5 is a time chart for explaining the operation of FIG. 4. In the figure, 1 is a printing paper, 2 is a tractor, 3 is a tractor shaft, 4 is a type conveyor, 5 is a paper feed motor, 6 is a pinion, 7 is an intermediate gear, 8 is a clutch, 9 is a manual knob, 10 is a tractor gear, 11 is a paper feed controller, 12 is a motor drive circuit, 13, 23, 28, 30 are OR gates, 14 is an octal up/down counter, 15, 2
1 and 24 are AND gates, 16 is a flip-flop, 17 is a quaternary counter, 18 and 27 are delay circuits, 19 is a one shot, 20 and 26 are D flip-flops, 22 and 25 are pulse generators, 29 is a NAND gate, 31 and 32 is a resistor, and 33 is an up/down switch.

Claims (1)

[Claims] 1 A motor that sends one line of printing paper in M steps, and an M motor that counts the number of drive pulses that drive the motor and generates an output when a predetermined value is counted.
A base up-down counter, a counter that counts the output of the M-base up-down counter and generates an output every time it counts N, and receives the output of the counter and stops the motor after the counter counts N. a printing position fine adjustment switch having at least two fixed contacts, UP and DOWN; processing means for adding (N-
A paper feed fine adjustment device characterized by feeding paper by l/M) lines or (N+l/M) lines.