JPH02305674A - Serial printer - Google Patents

Abstract

PURPOSE:To enable a circuit section to be commonly used for mechanical sections of various lateral lengths and at the same time, simplify the maintenance services of subject printer by providing a drive system in which a drive source does not respond to a printing head smoothly when the horizontal movement of the head is interrupted by more than a specified force and counting the displacement value of the head upto a sensor provided at one end after the drive of the head in the direction of the sensor following the drive to the other end by a fixed displacement, if the sensor is detected when power supply is turned ON. CONSTITUTION:A circuit section 14 receives a signal from a host device and controls a head feed motor and an output from a microswitch. Then the section 14 drives a stepping motor 7 to move a head 4 to the left so that the head 4 moves to a switch 12. Next the section 14 drives the stepping motor 7 so that the head 4 moves to the right by a fixed displacement value. This displacement value is determined by the possible lateral length of a mechanical section used commonly by the circuit section 14. The section 14 drives the stepping motor 7 with the counting of the displacement value so that the head 4 moves to the left again. Thus the lateral length of the mechanical section can be determined.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a serial printer, and particularly to a serial printer in which one type of circuit section can be used in common.

[Conventional technology]

Conventionally, such serial printers have various widths depending on the paper used, etc. In this case, it is common practice to design the mechanical part by changing only the width thereof, and to use almost the same circuit part. However, if the circuit section does not have information about the width of the mechanism section, when data is sent by mistake, the head will collide with the right edge, causing the head position to be incorrect. Therefore, conventionally, this type of circuit section is equipped with a dip switch, etc., and the width of the mechanism section in which the circuit section is used is set in advance. .

[Problem to be solved by the invention]

The above-mentioned conventional serial printer has the disadvantage that it is expensive due to the dip switches and the like, and that it is costly in terms of management because the circuit parts are not completely common.

SUMMARY OF THE INVENTION An object of the present invention is to provide a serial printer in which such a circuit section can be commonly used in mechanical sections of various widths, thereby reducing the price and making management easier.

[Means to solve the problem]

The serial printer of the present invention is a serial printer in which a print head moves horizontally with respect to paper to perform printing, and has a sensor at one end of the print head in the horizontal direction to detect when the print head has reached that position. The other end has a structure that prevents the horizontal movement of the print head, and the horizontal drive system of the print head provides power to the drive source when the horizontal movement of the print head is not prevented by a force above a certain level. When the power is turned on, the head moves toward the sensor, and when the sensor is detected, the drive source is activated to move the print head a certain amount toward the other end. The device is driven, and then driven again toward the sensor, and the amount of drive until reaching the sensor is counted, and the width of the mechanism is determined and stored.

〔Example〕

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

FIG. 1 is a plan view of a serial printer showing an embodiment of the present invention.

As shown in FIG. 1, in this embodiment, a platen 3 is held between left and right frames 1 and 2. As shown in FIG.

The paper is wound around the platen 3 during printing, and the platen 3 is rotated by a drive source (not shown) to determine the vertical position of the paper. Further, the platen 3 serves as a paper receiver during printing by the head unit 4.

This head portion 4 is suspended on guide shafts 5 and 6 fixed between frames 1 and 2, and slides in the left-right direction. A pulley 8 is fixed to the shaft of the head-feeding step motor 7, and a belt 9 is engaged with the pulley 8. A part of the belt 9 is the head part 4
Since the step motor 7 rotates, the horizontal position of the head section 4 is determined.

Further, on the head unit 4, there is a thermal transfer print head 10, an ink ribbon 11, and a ribbon motor (not shown).
It consists of a printing head pressing/release mechanism, a sliding section, etc., and prints using a well-known technique.Furthermore, a microswitch 12 is fixed to the left frame 1, and when the head section 4 reaches the left end, , a part of the head section 4 presses the feeler of the micro switch 12 and switches 1
Turn on 2. In other words, it works as a position sensor.

On the other hand, the circuit section 14 is placed behind the above-mentioned mechanism section, receives signals from the host device, and serves as the above-mentioned platen rotation motor and head feeding motor.

Controls head drive, head pressing/release, ribbon motor, micro switch output, etc. Incidentally, although wiring is not shown, the circuit section 14 and each motor etc. are naturally connected.

Next, the operation of the printer described above will be explained.

First, the step motor 7 is driven so that the head section 4 moves toward the switch 12. Switch this operation to switch 1
By repeating this until the output No. 2 is turned on, the head section 4 comes to the left end. However, if the output of the switch 12 is turned on immediately when the power is turned on, the head section 4 is once moved slightly to the right, and then the above operation is performed.

Next, the step motor 7 is driven to move the head section 4 by a certain amount in the right direction. This amount of drive is determined by the width of the mechanism section with which the circuit section 14 may be used. - As an example, assume that the mechanism is for an 8° digit and a 132 digit. Furthermore, if this narrower mechanical section has some margin, that is, if the print head 4 is physically able to move 85 digits, the above drive amount will be 86 digits (or more).

In this case, if the mechanism is for 132 digits, the print head 4 will move by 86 digits.

If it is 80 digits, the print head 4 is on the right frame 2.
The step motor 7 will step out of step, and the print head 4 will stop at any position below the 85th digit.

Thereafter, the step motor 7 is driven to move the print head 4 to the left again while counting the amount of movement. It is clear from the above that if the output of switch 12 is the 85th digit or below, the mechanism used at this time is for the 80th digit, and if the output is the 86th digit, it is for the 132nd digit. Become.

Therefore, the value is stored in the storage section in the circuit section 13.

In the above explanation, the drive unit is a step motor, and an example using the step-out phenomenon has been explained. A similar effect can be obtained if a step motor is used, and the use of a step motor is not a prerequisite.

〔Effect of the invention〕

As explained above, the present invention provides a serial printer that has a sensor at the left end of the head operation range, and the right end that obstructs the head operation beyond a certain amount and causes the drive system for horizontal movement of the head to exceed a certain amount. The head is configured so that the drive source and the head do not match when force is applied, and when the power is turned on, the head first moves to the left end, then moves a certain amount to the right, and then moves to the left again. By counting the amount of movement at that time, the width of the mechanical part can be determined, so mechanical parts with different widths can be commonly used in one type of circuit part, which is inexpensive and easy to manage. There is an effect that it can be done.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a schematic mechanism of a serial printer showing an embodiment of the present invention.

DESCRIPTION OF SYMBOLS 1... Left frame, 2... Right frame, 3... Platen, 4... Head part, 5, 6... Guide shaft, 7... Step motor, 8... Pulley, 9・、
...Belt, 10...Print head, 11...Ink ribbon, 12...Micro switch, 14...Circuit section.

Claims (1)

[Claims] In a serial printer in which a print head moves horizontally relative to paper to perform printing, one end of the print head in the horizontal direction has a sensor that detects when the print head has reached that position, and the other end is a sensor that detects when the print head has reached that position. It has a structure that prevents horizontal movement, and when the horizontal movement of the print head is prevented by a force above a certain level, the horizontal drive system of the print head receives a signal given to the drive source and the print head. It consists of a drive system that does not correspond to the position of the
When the power is turned on, the head moves toward the sensor, and when the sensor is detected, the drive source is driven to move the head a certain amount toward the other end, and then the head is driven toward the sensor again until it reaches the sensor. A serial printer characterized by counting the quantity, determining and storing the width of the mechanism part.