JPH09277602A - Electric check writer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a printing position error between the advance and return paths of a reciprocating printing type electric check writer. SOLUTION: A sub-carriage 13 loaded with a wire dot type printing head 14 is mounted on a main carriage 12 through a shift mechanism and the main carriage 12 is mounted on a guide shaft 11. A shading plate 15 for detecting a position is provided to the subcarriage 13 and a photointerruptor 16 is arranged in the vicinity of the left end part of the guide shaft. The main carriage 12 runs to the left from a right-hand standby position to print the upper half part of one line on a check and prints the lower half part thereof on the check in its return path. Motor driving pulses before the shading plate 15 reaches the position of the photointerruptor 16 from an advance path printing position are counted to be stored. In the return path, pulse counting is started from the position of the interruptor and printing is started at a position reaching the count number recorded in the return path.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric check writer for check printing, and more particularly to a reciprocating print type electric check writer.

[0002]

2. Description of the Related Art An electric check writer is known in which a wire dot type printer head is mounted instead of a conventional type wheel. Some wire-dot type electric checkwriters are configured to print a single line by reciprocal printing by dividing a large number and symbol to be printed on a check into two up and down, due to size restrictions of the printer head. .

FIG. 4 shows an example of a printer section of a reciprocating print type electric check writer, in which a main carriage 2 is engaged with a guide shaft 1 installed on a frame (not shown),
A sub-carriage 3 is attached to the main carriage 2, and a wire dot printer head 4 is fixed to the sub-carriage 3 downward. The main carriage 2 is reciprocally driven along the guide shaft 1 by a feed mechanism (not shown) by a timing belt, and the sub-carriage 3 mounted movably forward and backward (up and down in FIG. 4) with respect to the main carriage 2, A carriage shift mechanism (not shown) including a solenoid or a motor and a cam is used to shift back and forth.

The means for matching the reciprocating print positions is a photo interrupter 5 arranged at a reference position near the left end of the guide shaft 1, a light shield plate 6 provided on the main carriage 2, or a photo sensor and a reflector plate. It is composed of a position detection mechanism.

The main carriage 2 is a guide shaft 1
From the standby position at the right end of the left to the printing area, print the upper half of the amount number on the check, shift the subcarriage 3 to the front at the left end position outside the printing area, and reverse the running direction. Then, print the lower half of the amount figure and return to the standby position at the right end.

The print control unit starts counting the drive pulses of the step motor for carriage travel when the printing of the upper half portion is completed when traveling to the left, and the light shielding plate 6 reaches the position of the photo interrupter 5. When the light path is blocked, counting is stopped and the count number is stored. Then, the pulse counting is started when the light-shielding plate 6 reaches the position of the photo interrupter 5 by starting the traveling on the returning route, and the printing on the returning route is started when the count value reaches the same number as the stored count number. By doing so, the print positions of the forward pass and the return pass are matched.

However, since the sub-carriage 3 mounted so as to be movable back and forth with respect to the main carriage 2 has a clearance in the left-right direction due to its structure, the sub-carriage is caused by frictional resistance between the printer head and the ink ribbon during printing. As shown in FIG. 5, a stress acts on No. 3, and the carriage is displaced to the right with respect to the main carriage on the outward path (a) (the clearance is exaggerated in the drawing) and is displaced to the left on the return path (b). . Therefore, the main carriage 2
When the positional displacement of the sub-carriage 3 with respect to occurs,
As shown in FIG. 6, there is a problem that a print position error occurs in the upper half part and the lower half part of the character.

Therefore, there arises a technical problem to be solved in order to eliminate the printing position error and prevent the deterioration of the printing quality, and an object of the present invention is to solve the above problems.

[0009]

SUMMARY OF THE INVENTION The present invention is proposed to achieve the above object, and is a main carriage which is reciprocally driven left and right along a guide shaft installed on a frame of a check writer, and the main carriage. And a sub-carriage mounted on the
An electric check writer for reciprocal printing by a printer head fixed to a sub-carriage and facing a platen, an optical sensor disposed on a traveling path of the main carriage, and a light shielding plate or a reflection plate mounted on the main carriage. In the electric check writer that controls the print position in the digit direction based on the detection signal of the carriage detection unit, the detection unit is provided in the sub-carriage, The present invention provides an electric check writer characterized by detecting the positions of a sub-carriage and a printer head with a sensor.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. For the convenience of description, conventionally known technical matters will be described. FIG. 1 shows a printer section of an electric check writer, where 11 is a guide shaft and 12 is a main carriage. Although not shown, the guide shaft 1
A carriage driving mechanism is composed of a timing belt wound around pulleys arranged on the left and right along 1 and a step motor or a servo motor driving one pulley, and one point of the timing belt is attached to the main carriage 12. The main carriage 12 is driven to move left and right.

The sub-carriage 13 is mounted on the main carriage 12 so as to be movable back and forth (up and down in FIG. 1) via a known carriage shift mechanism (not shown) including a solenoid or a motor and a cam, and a wire dot type printer head. 14 is fixed downward.

A shading plate 15 is provided on the upper surface of the sub-carriage 13.
And a photo interrupter 16 is disposed above the reference position near the left end of the guide shaft 11. The light emitting portion 16a and the light receiving portion 1 of the photo interrupter 16
The optical path between the light emitting portion 16a and the light receiving portion 16b is orthogonal to the traveling direction of the main carriage 12, and the distance between the light emitting portion 16a and the light receiving portion 16b is dimensioned so as not to interfere with the light shielding plate 15 in the front and rear shift range of the sub carriage 13. .

When a print execution command is input to the print control unit, the main carriage 12 moves to the standby position IP shown in FIG.
From the left to the position S _R at which a preset number of drive pulses are output to the main carriage drive motor.
Then, the print data for each vertical line of the upper half of one row is serially transferred to the printer head 14 to start printing. This causes the upper half of a line to be printed from right to left at a predetermined position on the check set on the electric check writer. Then, the counting of the motor drive pulse is started from the position S _L at which the printing of the forward path is completed, and the light receiving unit 16 when the light blocking plate 15 reaches the position of the photo interrupter 16 and blocks the optical path.
When the falling edge of the output signal of b is detected, counting is stopped,
The distance between the print end position S _L and the position of the photo interrupter 16 is stored as the number of pulses.

Then, the vehicle further travels leftward and stops at the left end reversal position RP, and the subcarriage 13 is shifted forward. Then, the traveling direction is reversed to start traveling to the right, the light shielding plate 15 of the sub-carriage 13 enters between the photo interrupters 16 and the output signal of the light receiving unit 16b drops to the low level, and then the photo interrupter 16 When the output signal passes through 16 and changes to a high level, the rise is detected and pulse counting is started. The position S _L at which the count reaches the count recorded on the outward path
The printing of the lower half portion of one line is started according to the print data, and after the printing is completed, the sub-carriage 13 is shifted rearward to return to the standby position IP and the printing of one line is completed.

Since the print start position is controlled based on the actual positions of the sub-carriage 13 and the printer head 14 in this way, even when the sub-carriage 13 is displaced in the left-right direction with respect to the main carriage 12, There is no error in the print start position.

FIG. 3 shows another embodiment, in which a reflection type photo sensor 21 is arranged above the left end of the guide shaft 11 and a reflection plate 22 is provided on the upper surface of the sub-carriage 13, so that the sub-carriage 13 and the printer head are provided. The position of the sub-carriage 13 is detected.
The traveling distance detection is performed in the same manner as described above.

The present invention is not limited to the above-mentioned embodiment, and a sensor of another type such as a magnetic sensor may be used as the sensor. In addition, a servo motor is used as the carriage drive motor, and a rotary encoder is attached to the servo motor to configure carriage movement amount measuring means.
Various modifications are possible within the technical scope of the present invention, and it goes without saying that the present invention extends to those modifications.

[0018]

As described above, since the electric check writer of the present invention detects the position of the sub-carriage on which the printer head is mounted and controls the reciprocal print position, the print position is changed depending on the position of the conventional main carriage. Different from the control of (1), it is possible to eliminate the error in the printing position due to the left-right clearance between the main carriage and the sub-carriage, and the printing quality is improved.

[Brief description of drawings]

FIG. 1 is a plan view of a printer unit of an electric check writer according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a printing operation of the electric check writer of FIG.

FIG. 3 is a plan view of a printer unit of the electric check writer according to another embodiment of the present invention.

FIG. 4 is a plan view of a printer unit of an electric check writer showing a conventional example.

FIG. 5 is an explanatory diagram showing the positional displacement of the sub-carriage with respect to the main carriage.

FIG. 6 is an explanatory diagram showing a print position error in a conventional electric check writer.

[Explanation of symbols]

 11 Guide Shaft 12 Main Carriage 13 Sub Carriage 14 Wire-Dot Printer Head 15 Light-Shielding Plate 16 Photointerrupter 16a Light-Emitting Unit 16b Light-Receiving Unit 21 Reflective Photosensor 22 Reflector

Claims (1)

[Claims] 1. A main carriage which is reciprocally driven left and right along a guide shaft installed on a frame of a check writer, a sub-carriage mounted on the main carriage via a row-direction shift mechanism, and a platen fixed to the sub-carriage. An electric check writer that performs reciprocal printing with a printer head facing the printer head, comprising: an optical sensor disposed on the traveling path of the main carriage; and a detected portion such as a light shielding plate or a reflection plate mounted on the main carriage. In an electric check writer that constitutes a carriage detection means and controls a print position in the digit direction based on a detection signal of the carriage detection means, the sub-carriage (13) is provided with the detected portion (15), and the optical sensor is provided. Subcarriage (1
3) An electric check writer which detects the positions of the printer head (14).