JPH0345372A - Apparatus for automatically adjusting gap between printing head and platen - Google Patents

Abstract

PURPOSE:To always automatically adjust a definite gap in a cold or hot district, in securing the predetermined gap between a printing head and a platen by reversing a pulse motor by a predetermined step, by correcting the number of reverse steps by a control part to reverse the pulse motor. CONSTITUTION:When the gap between a printing head 11 and a platen 1 is set in a cold or hot district different from the normal temp., the reference value at the normal temp. of the number of the rotary steps of a pulse motor 6 revolving a cam 5 until the platen moves from a home position to come into contact with the printing head 11 and the value of the number of changed rotary steps are detected by the comparator 19 of a control part 16. The signal of the number of the changed rotary steps is inputted to the reverse step number correction circuit 20 of the pulse motor 6 to correct the number of reverse steps reversing the pulse motor 6 from the ON-position of a push switch 4 and the pulse motor 6 is reversed to secure a predetermined gap.

Description

[Detailed Description of the Invention] [Summary] The present invention relates to an automatic gap adjustment method between a print head and a platen, and the gap setting between the print head and the platen remains constant regardless of environmental conditions, that is, cold regions or hot regions. The purpose of this is to automatically adjust to the gap between the print head and the platen, which is moved in the direction of the print head by a cam driven by a pulse motor, and a second platen, which is moved along the platen by a carrier. When setting the gap between the platen and the print head, a pulse motor rotates the cam so that the platen moves from its home position, and when the platen comes into contact with the print head, it is pressed. In the automatic gap adjustment method between the print head and platen, when the dynamic switch is turned on, the pulse motor rotates in a predetermined step in reverse from that position to ensure a predetermined gap.When setting the gap between the print head and platen at room temperature, The number of rotational steps of the pulse motor that rotates the cam until the platen moves from the home position and comes into contact with the print head is stored in advance in a storage device that constitutes the control unit, and the gap can be set at a temperature different from room temperature. Sometimes,
Until the platen moves from the home position and comes into contact with the print head, the pulse motor is operated from the on position of the push switch to a predetermined value by the change in the number of rotation steps of the pulse smoke that rotates the cam from that at room temperature. The present invention is characterized in that, when securing a predetermined gap during step reversal, the control section corrects the number of reversal steps to reverse the pulse motor.

[Industrial application field]

The present invention relates to an automatic print head and platen gap adjustment method, and the gap setting between the print head and platen is automatically adjusted to a constant gap regardless of environmental conditions, that is, cold regions or hot regions. It is something.

[Conventional technology]

FIG. 3 is a front view schematically showing a printing unit having an automatic gap setting mechanism of a passbook printer of a terminal device of a computer system used in financial institutions, such as banks, and FIG. 4 is a right side view of the same. ■ is a kamaboko-shaped platen,
2 is a guide member that slidably holds this platen;
The upper end of the platen 1 protrudes from the upper end of the guide member 2, and the platen 1
A protruding portion 1 a formed at the lower end of the guide member 2 protrudes from the lower end of the guide member 2 . Note that if the platen 1 is fixed to the guide member 2 and the guide member 2 is slidably attached to the holding member 3 with a predetermined sliding resistance, the guide member 2
A protrusion for pressing a push switch, which will be described later, may be formed at the lower end.

Reference numeral 4 denotes a push switch attached to the lower piece 3a of the L-shaped holding member 3, specifically a keyboard switch used in a keyboard or the like. The upper surface of the push switch 4 is in contact with a protrusion 1a at the lower end of the platen 1, and when the platen 1 moves downward, it is pressed by the protrusion 1a and turned on. There is.

5 is a cam, which is attached to the lower piece 3a of the above-mentioned cursor-shaped holding member 3.
The center part of the lower surface of the cam 5 is in contact with the cam 5, and the cam 5 is rotated by a heald 8 hooked between the boo IJ 5a provided on the cam 5 and a pulley 7 attached to the rotating shaft of the pulse motor 6. It looks like this. When this cam 5 is driven by the pulse motor 6 and rotates, the above-mentioned L-shaped holding member 3
The platen 1 is moved up and down via the guide member 2.

A carrier 9 moves along the platen I guided by guide rods 10, 10, and a print head 11 and a mask 12 are fixed to this carrier.

Reference numeral 13.13 denotes a traction spring provided to move the L-shaped holding member 3 downward when the cam 5 rotates downward.

Reference numeral 14.14 denotes a guide rod provided perpendicularly to the lower surface of both ends of the L-shaped holding member 3, which is fitted into the guide rod receiving portion 15.15, so that the L-shaped holding member 3 is held in parallel. It is designed to move up and down.

When setting the gap between the platen 1 and the print head 11, the cam 5 is rotated from the home position of the platen 1 by the pulse motor 6, and the cam 5 moves the platen 1 through the above-mentioned cross-shaped holding member 3. is pushed up and when this platen ■ comes into contact with the print head 11 through the mask 12, this platen l moves downward and is pressed by the protrusion 1a at its lower end, turning on the push switch 4. Then, the pulse motor 6 reverses a predetermined step from that position, rotates the cam 5 downward, moves the platen 1 downward via the L-shaped holding member 3, and secures a predetermined gap. This is what I did.

[Problem to be solved by the invention]

By the way, as shown in FIG. 5, the push switch 4 has a fixed contact 4a and a movable contact 4b covered with a soft synthetic resin 4C. This soft synthetic resin has the property of becoming hard when it cools down in cold regions, and becoming soft when it warms up in hot regions.

Therefore, in a cold region, when the push switch 4 gets cold and the soft synthetic resin 4c becomes hard, the pulse sweater 6 rotates the cam 5 from the home position of the platen when setting the gap between the platen 1 and the printing pad 11. The number of steps taken by the pulse motor 6 until the platen 1 pushed up as described above by the cam 5 contacts the print head 11 via the mask 12 and the push switch 4 is turned on is as follows: It becomes more than it is in time. This is because the soft synthetic resin 4c that forms the push switch 4 is hard, so when the platen 1 is moved a lot in the direction of the print head 11, the reaction force causes the protrusion 1a at the lower end of the platen 1 to be strongly pressed against the soft synthetic resin. Push switch 4 cannot be turned on unless 4c is pressed. and,
When the platen 1 is separated from the print head 11 by a certain distance from the position where the push switch 4 is turned on via the pulse motor 6 and the cam 5 in the same way as at room temperature, the platen 1 and the print The gap with the head 11 is narrower than that at room temperature.

In addition, in hot regions, if the push switch 4 is warmed up and the soft synthetic resin 4c becomes soft, the pulse motor 6 may be activated when setting the gap between the platen l and the print head 11.
As a result, the ζ cam 5 is rotated from the home position of the platen=81, and the platen 1 pushed up as described above by the cam 5 comes into contact with the print head 11 through the mask 12, and the push switch is pressed. 4
The number of steps of the pulse motor 6 until it turns on is smaller than that at room temperature.

This is because the soft synthetic resin 4C that forms the push switch 4 is soft, so the platen 1 is connected to the print head 11.
In other words, platen 1 does not need to be moved much in the direction of
This is because even if the soft synthetic resin 4c is weakly pressed with the protruding portion 1a at the lower end of the push switch 4, the push switch 4 is turned on.

From the position where this push switch 4 is turned on,
If the platen 1 is separated from the print head 11 by a certain amount via the pulse motor 6 and cam 5 in the same way as at room temperature, the gap between the platen 1 and the print head 11 will be the same as that at room temperature. becomes wider than

As explained above, even if the gap between the platen 1 and the print head 11 is designed to be a predetermined value at room temperature, the gap will change in cold or hot regions. I had the problem mentioned above.

This invention was devised in view of these problems, and the gap between the print head and the platen is automatically adjusted to a constant gap three times around regardless of environmental conditions, such as cold or hot regions. The purpose is to ensure that the

[Means to solve the problem]

As a means for solving the above-mentioned problems, the present invention is directed to the direction of the print head by a cam 5 driven by a pulse motor 6, as shown in FIGS. 1, 2, 3, and 4. It consists of a platen 1 that is moved along the platen L and a print head 11 that is moved along the platen L by a carrier 9. When setting the gap between the platen 1 and the print head 11, the pulse motor 6 When the cam 5 is rotated so that the platen 1 moves from the home position, and when the platen 1 comes into contact with the print head 11 and is pressed and the push switch 4 is turned on, the pulse motor 6 starts from that position. In the automatic gap adjustment method between the print head and the platen, which ensures a predetermined gap by reversing steps, when setting the gap between the print head 11 and the platen 1 at room temperature, the platen 1 moves from its home position and the print head The number of rotational steps of the pulse motor 6 that rotates the cam 5 until it comes into contact with the cam 11 is stored in advance in the storage device 17 that constitutes the control unit 16, and when the platen 1 is set at a temperature different from normal temperature, the platen 1 is Print head 11 after moving from the position
The number of rotational steps of the pulse motor 6 that rotates the cam 5 until the cam 5 comes into contact with the cam 5 is changed from that at room temperature by reversing the pulse motor 6 by a predetermined step from the position where the push switch 4 is on, and then rotating the cam 5 to a predetermined gap. An automatic print head-platen gap adjustment method, characterized in that the control unit 16 corrects the number of reverse rotation steps to reverse the pulse mode 6 when ensuring the following: By means of the above-mentioned means, in the manufacturing adjustment process, when setting the gap between the platen l and the print head 11 at room temperature, the pulse motor 6 controls the cam 5.
When the platen 1 is rotated from the home position of the platen 1, and when the platen 1 comes into contact with the printing spatula F11, it is pressed and the push switch 4 is turned on, and the pulse motor 6 reverses by a predetermined step from that position to rotate the printing head. A pulse motor 6 rotates the cam 5 until the platen 1 moves from the home position and comes into contact with the print head 11 and the push switch 4 is turned on when setting a predetermined gap between the platen and the platen. The number of rotation steps is stored in advance in the storage device 17 that constitutes the control unit 16.

By doing this, when setting a gap in a cold region or a hot region where the temperature is different from normal temperature, the number of rotation steps of the pulse motor 6 that rotates the cam 5 until the platen 1 moves from the home position and comes into contact with the print head 11. When reversing the pulse motor 6 by a predetermined step from the on position of the push switch 4 to ensure a predetermined gap, the control section 16 corrects the number of reversal steps to compensate for the change from that at room temperature. Reverse the pulse smoker.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail according to FIGS. 1 and 2, together with FIGS. 3 and 4.

FIG. 1 is a control system diagram of an embodiment of the present invention, and FIG. 2 is a diagram showing an embodiment of the control section. When setting the gap between the platen 1 and the print head 11, the pulse motor 6 moves the cam 5 to the platen. 1 is rotated so as to move from the home position, and when the platen 1 comes into contact with the print head 11 and is pressed and the push switch 4 is turned on, the pulse motor 6 reverses from that position by a predetermined step. The point of ensuring a predetermined gap is that the gear knob automatic adjustment method between the print head and the platen is conventionally known. The method described below has been applied.

That is, the present invention includes a rotation step of the pulse motor 6 that rotates the cam 5 until the platen 1 moves from the home position and comes into contact with the print head 11 when setting the gap between the print head 11 and the platen 1 at room temperature. The number is stored in advance in the storage device 17 constituting the control unit 16, and when setting the gap at a temperature different from room temperature, the cam 5 is moved until the platen 1 moves from the home position and comes into contact with the print head 11. When the pulse motor 6 is reversed by a predetermined step from the ON position of the push switch 4 to ensure a predetermined gap, the control is performed to compensate for the change in the number of rotation steps of the pulse motor 6 to be rotated from that at room temperature. The unit 16 is configured to correct the number of reverse rotation steps and rotate the pulse motor 6 in the reverse direction.

In addition, 18 shown in FIG. 1 is a home position sensor of the platen 1, and the rotation of the cam 5 causes the platen l to
When the printer starts moving from the home position toward the print head 11, a movement start signal is sent from the home position sensor 18 to the control section 16, and counting of the number of rotation steps of the pulse motor 6 is started.

Further, line L1 indicates an electrical system, and line L2 indicates a mechanical system.

FIG. 2 shows an embodiment of the control unit 16, in which the storage device 1
7, the print hand 11 and platen 1 are placed at room temperature in advance.
When the gap between
The number of rotational steps of the pulsed black, which rotates the rotor, ie, the reference value, is being written. This reference value is applied to one input terminal of the comparator 19, and the other input terminal 5 is applied to the platen 1, which is driven by the cam 5 when used in various environments such as cold regions and hot regions. A signal indicating the number of rotational steps of the pulse motor 6 until it moves from the home position and comes into contact with the print head 11 is applied.

By doing this, when setting a gap in a cold region or a hot region where the temperature is different from normal temperature, the rotation step of the pulse motor 6 that rotates the cam 5 until the platen 1 moves from the home position and comes into contact with the print head 11. The comparator 19 detects the number of rotation steps that has changed from that at normal temperature. The signal of this changed rotational step number is sent to the reverse rotation step number correction circuit 2 of the pulse motor 6.
0 to correct the number of reversal steps for reversing the pulse motor 6 from the position where the push switch 4 is on,
The pulse motor 6 is rotated in reverse to ensure a predetermined gap.

〔Effect of the invention〕

The present invention has the advantage that the predetermined gap setting between the print head and the platen can be automatically adjusted to a constant gap regardless of environmental conditions, ie, cold regions or hot regions.

[Brief explanation of drawings]

Fig. 1 is a control system diagram of an embodiment of the present invention, Fig. 2 is a diagram showing an embodiment of the control unit, and Fig. 3 is a diagram of a passbook printer of a terminal device of a computer system used in financial institutions, such as banks. FIG. 4 is a front view schematically showing a printing section having an automatic gap setting mechanism, FIG. 4 is a right side view thereof, and FIG. 5 is a sectional view of a push switch. 1...Platen, 2...Guide member, 3...
...Holding member, 4...Push switch, 5...
・Cam, 5a...Pulley, 6...Pulse motor, 7...Pulley, 8...Held,
9...Carrier, 10...Guide rod, 1
1...Print head, 12...Mask, 13
... Traction spring, ... Guide rod, 15.
...Guide rod receiving part, ...Control part, 17...
Memory device,...Platen home position sensor...Comparator,...Pulse motor reverse step number correction circuit. Cross-sectional view of the right side view push switch in Figure 3

Claims (1)

[Claims] A platen (1) provided to be moved in the direction of the print head by a cam (5) driven by a pulse motor (6).
and a print head (11) provided to be moved along the platen (1) by a carrier (9). When setting the gap between the platen (1) and the print head (11), the pulse motor (6) ) rotates the cam (5) so that the platen (1) moves from the home position, and when the platen (1) comes into contact with the print head (11), it is pressed and the push switch (4) is activated. When the pulse motor (6) is turned on, the pulse motor (6) reverses by a predetermined step from that position to ensure a predetermined gap.In the automatic gap adjustment method between the print head and the platen, the print head (11) and the platen (1) at room temperature. When setting the gap between the two, the control unit ( storage device (17) constituting the
), and when setting the gap at a temperature different from room temperature, a pulse motor ( 6) When the pulse motor (6) is reversed by a predetermined step from the on position of the push switch (4) to ensure a predetermined gap, the control An automatic gap adjustment system between a print head and a platen, characterized in that a section (16) is configured to correct the number of reverse rotation steps and reverse the pulse motor (6).