JPH091906A - Ink ribbon controller for printer - Google Patents

Abstract

PURPOSE: To prevent the overriding failure of an ink ribbon bar due to the slack of an ink ribbon generated when the tension of the ribbon is released. CONSTITUTION: When an ink ribbon send signal is outputted from a control circuit via a signal line 11 at the time of printing, a switch 21 is closed, one of ink ribbon drive motors 15, 16 selected by an inverting switch 18 is driven to up or down wind the ribbon to send the ribbon. Except the time of printing, when a type conveyor and a hammer are closed therebetween, the switch 21 is opened, the switch 20 is closed by an ink ribbon tension signal, the motors 15, 16 are energized, and tension is given to the ribbon. When operation comes in a tension release mode, an ink ribbon tension release signal is intermittently output by a timer control to control to intermittently turn on, off the switch 20, the energization and deenergization of the motors 15, 16 are released, and the switch is then controlled to be stopped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink ribbon control device for a printer using an ink ribbon with a return bar, and more particularly, to the slack of the ink ribbon which occurs when the ink ribbon is released from the tension release mode. The present invention relates to a technique for preventing an ink ribbon return bar from getting over.

[0002]

2. Description of the Related Art A conventional printer of this type includes two roll bobbins for winding an ink ribbon with a return bar and a ribbon drive motor corresponding to each roll bobbin, and the ink ribbon feeding operation during printing is performed. When the roll is wound on one roll bobbin by the specified amount (full), the return bar contacts the return arm of the reversing switch mechanism and the ink ribbon is wound on the other roll bobbin side. Is reversed.

An ink ribbon with a return bar and its ribbon feeding mechanism (ribbon winding mechanism) will now be described with reference to FIGS.

As shown in FIG. 3A, the ink ribbon 1
4 is roll bobbins 12 and 12 for winding two ribbons
'And ribbon drive motors 15 and 16 corresponding thereto
(See FIG. 4). 13, 13 'is the ink ribbon 1
3 is a return bar arranged in FIG. 4, and FIG. 3B shows the return bar 1 that appears when the ink ribbon 14 is in the unfolded state.
The attached state of 3,13 'is shown. Usually, the ink ribbon 14
Is set in a ribbon feeding mechanism (ribbon winding mechanism) as shown in FIG. 4, the roll bobbins 12, 12 '
And the corresponding ribbon drive motors 15 and 16 are arranged vertically, and the upper roll bobbin 12 and its ribbon drive motor 15 are used for upper winding, and the lower roll bobbin 1
2'and its ribbon drive motor 16 are used for lower winding. One return bar 13 is attached at a position near the upper winding side bobbin 12, and the other return bar 13 'is attached at a position near the lower winding side bobbin 12'.

At the time of printing, the ink ribbon 14 is in a feeding state, and when the ink ribbon 14 is wound up (ribbon top feeding), the ribbon drive motor 15 is driven,
When the ink ribbon 14 is wound around the upper roll bobbin 12 by a specified amount (allowable amount), as shown in FIG.
The lower return bar 13 'comes into contact with the return arm 17 of the reversing switch mechanism 18, and one of the reversing switches 18 is closed by the swinging operation of the arm. As a result, the operation is switched from the ribbon drive motor 15 to the ribbon drive motor 16, the ink ribbon 14 travels in reverse, and is wound around the lower winding side bobbin 12 '(ribbon lower feed). When the ink ribbon 14 is wound around the lower winding bobbin 12 'by a specified amount, the upper return bar 13' comes into contact with the return arm 17 and the other of the reversing switch 18 is turned on, as shown in FIG. 5B. close. Thereby, the ribbon drive motor 16 to the ribbon drive motor 15
The operation is switched to, and the ink ribbon 14 runs again in reverse in the upward feeding direction.

Generally, the upper and lower winding ribbon drive motors 15 and 16 have the same specifications. The upper and lower winding ribbon drive circuits have the same specifications.

[0007]

The above-mentioned ink ribbon feeding mechanism normally feeds the ink ribbon during printing, and is in a feeding stopped state except during printing. When the ink ribbon feeding is stopped, tension is applied to the ink ribbon to prevent loosening. This tension is equivalent to a direction in which an ink ribbon tension signal is applied from the control mechanism to the ribbon drive motors 15 and 16 to excite the ribbon drive motors 15 and 16 so that the motors 15 and 16 apply tension to the ink ribbon 14. This is done by producing torque (low torque).

By the way, the ink ribbon can be exchanged in a state where the space between the character carrier and the hammer is opened and the tension of the ink ribbon is released. For this reason, the tension of the ink ribbon is released when the space between the character carrier and the hammer is released. The space between the type conveying member and the hammer is opened not only when the ink ribbon is replaced but also when the printing paper is set and the printing state is confirmed, and in this case, the tension of the ink ribbon is released.

This tension release is performed by turning off the excitation of the upper winding ribbon drive motor 15 and the lower winding ribbon drive motor 16 by the tension release signal (motor drive stop signal), but the following improvements should be made. There was a point.

That is, when the tension is released (the drive motors 15 and 16 are de-energized) from the state in which the tension is applied to the ink ribbon 14, a contracting force acts on the ink ribbon 14 to cause the two drive motors 15 and 16 to move. 16 freely rotates in a direction opposite to the rotation that gives tension to the ink ribbon 14. This rotation causes slack in the ink ribbon 14. When the slack of the ink ribbon 14 occurs in the maximum state of the upper winding, thereafter, the space between the type conveyance body and the hammer is closed, and the motors 15 and 1 are connected to the ink ribbon 14 again.
Return bar 13 when tensioned by 6
′ Causes the return arm 17 to get over. If it gets over, troubles such as inability to control the inversion of the ink ribbon will occur, stable ink ribbon feeding will not be possible, and there is a risk that the return bar will bite between the type conveyance body and the hammer and be damaged. It was

The present invention has been made in view of the above points, and it is an object of the present invention to prevent defective overcoming of the ink ribbon return bar due to loosening of the ink ribbon that occurs when the tension of the ink ribbon is released.

[0012]

In order to achieve the above-mentioned object, the present invention comprises two roll bobbins for winding an ink ribbon with a return bar and a ribbon drive motor corresponding to each roll bobbin, and during printing. When the ink ribbon is wound on one roll bobbin by a specified amount during the ink ribbon feeding operation, the return bar comes into contact with the return arm of the reversing switch mechanism to wind the ink ribbon on the other roll bobbin side. In an ink ribbon control device of a printer for reversing an ink feeding operation, an ink ribbon tension that outputs a tension command signal to the ribbon drive motor while the feeding operation of the ink ribbon is stopped to apply a tension to the ink ribbon by the ribbon drive motor. In addition to the control means, when the ink ribbon tension release mode is entered, the revolving Providing an ink ribbon tension release control means for stopping controlling said ribbon drive motor after intermittently outputs the ink ribbon tension release signal the timer control to the drive motor.

[0013]

According to the above construction, when the ink ribbon tension release mode is entered (when the space between the character carrier and the hammer is released),
The tension release signal is intermittently output to the ribbon drive motor by timer control. The intermittent drive signal causes the ribbon drive motor to repeat excitation (motor on) and excitation off (motor off) intermittently (intermittently). Thus, abrupt tension release is avoided and buffer tension release is performed, after which the ribbon drive motor is completely deenergized. Therefore, the free rotation of the ribbon drive motor is eliminated, the slack of the ink ribbon is prevented, and the ink ribbon returns even if tension is applied to the ink ribbon by exciting the ribbon drive motor again by closing the space between the print carrier and the hammer. The problem that the bar gets over the return arm of the reversing mechanism can be avoided.

[0014]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block circuit diagram of an ink ribbon control apparatus according to an embodiment of the present invention, and FIG. 2 is a circuit diagram of its motor driver. In addition, the ink ribbon feeding mechanism of the present embodiment is applicable to those described in FIGS.

The ink ribbon control apparatus shown in FIG. 1 includes a microprocessor 1, which is a control center, and an R, which is a peripheral element thereof.
It is composed of an OM (read only memory) 2, a RAM (random access memory) 3, a timer 4, an input / output port 5, a gate 6 and a ribbon motor driver 7. R
The OM2 includes an ink ribbon feeding operation, a tension applying operation,
The control program necessary for the tension release operation is stored.
The RAM 3 stores the data necessary for control from the outside. Data transmission between the microprocessor 1 and the peripheral circuits is performed via the data bus 9. 8 is an address bus.

As shown in FIG. 2, the ribbon motor driver 7 includes ribbon drive motors 15 and 16, a power source 19 for the motors, a reversing switch 18, a ribbon tension signal ON / OFF switch 20, and a ribbon feed signal ON / OFF switch 2.
1 is provided. Further, a ribbon drive motor low torque output resistor 22 and a phase advance capacitor 23 are provided for each of the drive motors 15 and 16.

Next, the functions of these circuits will be described in connection with the ribbon feeding operation at the time of printing of the printer and the tension and tension releasing operation at the time of printing stop.

[Feeding Operation of Ink Ribbon 14 During Printing] When the microprocessor 1 receives a print command signal via the data bus 9, the microprocessor 1 outputs the bit of the input / output port 5 based on the control program stored in the ROM 2. 4 outputs an ink ribbon feed signal to the ribbon motor driver 7 via the signal line 11. This ink ribbon feed signal switches the movable contact of the ribbon feed signal ON / OFF switch 21 shown in FIG. 2 from the solid line to the position of the chain line (the tension signal ON / OFF switch 20 has the movable contact in the OFF state of the solid line). As a result, the ribbon drive motor on the side selected by the reversing switch 18 (the upper winding ribbon drive motor 15 side in FIG. 2) becomes conductive, and the ink feeding operation is performed. The reversing switch 18 corresponds to the one shown in FIG.
The switch is switched by the return arm 17 of the return arm 17, and the return arm 17 is brought into contact with the return bars 13, 13 ′ (see FIGS. 3 to 5) provided on the ink ribbon 14 and swings to switch the reversing switch 18. .
That is, as shown in FIG. 5A, the ink ribbon 14 is fully wound (a prescribed amount) on the upper winding bobbin 12 by driving the motor 15, and the lower return bar 13 ′ hits the return arm 17. Upon contact, the drive motor 16 is selected by the reversing switch 18, and the ink ribbon 1
4 is wound up on the lower winding roll bobbin 12 'and reversely runs. After that, the ink ribbon 14 is fully wound around the lower winding bobbin 12 ′ by the drive of the motor 16, and the upper return bar 13 comes into contact with the return arm 17 as shown in FIG. The drive motor 15 is selected by the switch 18 and the ink ribbon 14 is reversed so as to be wound on the upper winding roll bobbin 12, and the ribbon feeding operation as described above is repeated in long-time printing.

[Regarding Tension Applying and Releasing Operation to Ink Ribbon 14 Other Than during Printing] The microprocessor 1 turns off the ribbon feeding signal of the signal line 11 and turns off the ribbon feeding signal ON / OFF switch 21 except during printing. It is in the OFF state (the movable contact of the switch 21 is in the solid line state position), and at this time, the signal line 1 is transmitted via the bit 3 of the input port 5.
The ink ribbon tension signal is output to 0. This tension signal causes the ink ribbon signal ON / OFF signal switch 20 to be in the ON state (the movable contact of the switch 20 is in the chain line position),
The drive motors 15 and 16 are excited, and at the same time, the motors 15 and 16 are given equal low torques in opposite directions to apply tension to the ink ribbon 14.
In this way, tension is applied to the ink ribbon 14.

Next, when the space between the character carrier and the hammer is opened by replacing the ink ribbon, setting the paper, etc., the microprocessor 1 receives the tension release (tension off) signal of the ink ribbon via the data bus 9 and inputs it. Bit 3 of the output port 5 is set to have no signal. As a result, the ink ribbon tension release processing is started as follows.

First, by turning off the signal in bit 3, the switch 20 is turned off via the signal line 10 (the movable contact of the switch 20 is in a solid line state), the excitation of the motors 15 and 16 is cut off, and the tension is temporarily set. Although it is released, the microprocessor 1 controls the timer 4 to pass through the gate 6 and the signal line 10 for about 300 ms and then 150 m.
The ink ribbon tension signal is output for s, the switch 20 is turned on again to excite the drive motors 15 and 16 to apply the ink ribbon tension, and then the ink ribbon tension signal is turned off for 180 ms (in other words, the tension release signal is output). Then, the switch 20 is turned off, and the excitation of the motors 15 and 16 is cut off. After that, the ink ribbon tension signal is output again for about 100 ms to excite the motors 15 and 16 to apply tension to the ink ribbon. After that, the ink ribbon tension signal is further turned off for 80 ms, and then the ink ribbon tension signal is output for 60 ms to turn on the switch 20 to apply tension.
The ink ribbon tension signal is continuously turned off.

With this arrangement, even after the bit 3 of the input / output port 5 is set to no signal, the tension signal on / off switch 20 of the ink ribbon is turned on by the pulse signal (several pulse control) to cause the ink ribbon tension. In the release mode, the ribbon drive motors 15 and 16 are stopped and controlled by intermittently outputting a tension release signal to the ribbon drive motors 15 and 16 by timer control.

Therefore, abrupt tension release is avoided with respect to the ink ribbon 14, buffer tension release is performed, and then the ribbon drive motors 15 and 16 are completely deenergized. Therefore, even if the free rotation of the ink ribbon drive motors 15 and 16 is eliminated, the slack of the ink ribbon 14 is prevented, and the tension is applied to the ink ribbon 14 by closing the space between the print carrier and the hammer again, the return bar 13 (13 ') is the return arm 17 of the reversing mechanism
It is possible to avoid problems such as overcoming. in this case,
As described above, by gradually narrowing the on / off time of the ink ribbon tension signal (the output time of the ink ribbon tension release signal and the output time of the ink ribbon tension signal during that period), the tension is released more smoothly.

[0025]

As described above, according to the present invention, an expensive ribbon drive motor or a special ribbon drive motor control circuit is not required, and the tension of the ink ribbon is released smoothly without causing the slack of the ink ribbon. In addition, it is possible to prevent a failure in getting over the return arm of the ink ribbon return bar.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of an ink ribbon control device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of a motor driver used in the above embodiment.

FIG. 3 is an explanatory diagram showing a winding state and an unfolded state of an ink ribbon to which the present invention is applied.

FIG. 4 is a partial perspective view of an ink ribbon feeding mechanism to which the present invention is applied.

FIG. 5 is an explanatory diagram showing a reversing operation state of the ink ribbon feeding mechanism.

[Explanation of symbols]

1. Microprocessor (ink ribbon tension control means,
Ink ribbon tension releasing means), 4 ... Timer, 7 ... Motor driver, 12, 12 '... Roll bobbin, 13, 13
´… Ink ribbon return bar, 14… Ink ribbon,
15, 16 ... Drive motor, 17 ... Return arm,
18 ... Inversion switch, 20 ... Ribbon tension signal ON / OFF switch, 21 ... Ribbon feed signal ON / OFF switch.

Claims (2)

[Claims] 1. A roll bobbin for winding an ink ribbon with a return bar and a ribbon drive motor corresponding to each roll bobbin are provided, and the ink ribbon is fed to one roll bobbin at a specified amount during an ink ribbon feeding operation during printing. In the ink ribbon control device of the printer, the return bar contacts the return arm of the reversing switch mechanism to reverse the ink feeding operation so that the ink ribbon is wound on the other roll bobbin side. Ink ribbon tension control means for outputting a tension command signal to the ribbon drive motor while the ribbon feeding operation is stopped to apply tension to the ink ribbon by the ribbon drive motor, and the ribbon drive motor when in the ink ribbon tension release mode. Ink ribbon tension release signal by timer control Ink ribbon control device of the printer, characterized in that it comprises an ink ribbon tension release control means for stopping controlling said ribbon drive motor after intermittently output. 2. The timer control for intermittently outputting the ink ribbon tension release signal is such that the output time of the ink ribbon tension release signal which is intermittently repeated and the output time of the ink ribbon tension signal in between are gradually narrowed. The ink ribbon control device of the printer according to claim 1, wherein