JP4014769B2 - Current supply cutoff device for printer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer current supply interrupting device that supplies and interrupts current to various parts including a control unit in a printer, and more particularly to a printer current supply interrupting device that enables low power consumption.
[0002]
[Prior art]
In recent years, with the development of portable personal computers and word processors, various battery-driven printers have been developed.
[0003]
First, the configuration of a conventional current supply cutoff device in this type of printer will be described.
[0004]
FIG. 2 shows an example of a conventional current supply cut-off device. In this conventional example, supply and cut-off of current from a power source 1 made of a battery are performed only by a simple switch 2.
[0005]
According to such a configuration, it is possible to simultaneously cut off and supply current to the control unit including the CPU and the operation unit 3 having a mechanism unit driven by a motor or the like by turning the switch 2 on and off with a simple configuration. it can.
[0006]
FIG. 3 shows another example of a conventional current supply cutoff device. In this conventional example, the current supply from the power source 1 made of a battery is supplied to two control systems in parallel, that is, a control unit 4 including a CPU. Branching to the mechanism unit 5 driven by a motor or the like, and the control unit 4 is continuously supplied with current, whereas the mechanism unit 5 is provided with a switch 6.
[0007]
According to such a configuration, even when the switch 6 is turned off, a current is always supplied to the control unit 4.
[0008]
[Problems to be solved by the invention]
However, in the case of FIG. 2, when the power source 1 is a battery, a large current flows when the voltage decreases, so the switch 2 becomes large, increasing the mounting space, increasing the cost, reducing the size, It cannot meet the demand for cost reduction. Further, when the switch 2 is opened, the control unit of the operation unit 3 is stopped. Therefore, if the switch 2 is opened during the paper discharge, the paper discharge is stopped without being completely performed. Become.
[0009]
On the other hand, in FIG. 3, even when the switch 6 is turned off, current is continuously supplied to the control unit 4, so that power is continuously consumed. For this reason, when the power source 1 is a battery, the capacity is reduced by discharging, so that the number of printable sheets may be reduced or the printer may not be used because it does not have the necessary electrical capacity when it is desired to use this printer. There is.
[0010]
The present invention overcomes such problems in the prior art, and not only can be reduced in size, but also can reduce power consumption, and can stop after completely discharging paper, In addition, an object of the present invention is to provide a printer current supply cutoff device that can be manufactured at low cost.
[0011]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the current supply cutoff device for a printer according to the first aspect of the present invention is characterized in that the first transistor for supplying the current of the power source to the operation unit and the ON state of the first transistor are continued. A first transistor that controls ON / OFF of both transistors synchronously, and a first switch that is turned on only during operation, and that activates the first transistor, and the operating unit. And a second port for detecting that the second switch is ON, and the controller turns on both the switches to cut off the current. When the work as the printer remains, the two ports are turned off by the first port after the work is finished. Further, by adopting such a configuration, not only can the paper discharge be stopped after it is completely discharged, but also the power is not supplied to the control unit at the time of stop, so that the power consumption can be reduced.
[0012]
According to a second aspect of the present invention, there is provided a printer current supply cutoff device according to the present invention, wherein the first switch and the second switch are two-pole single-throw switches that are turned ON / OFF synchronously. is there. By adopting such a configuration, the switch can be configured simply.
[0013]
According to a third aspect of the present invention, there is provided a printer current supply cutoff device according to the present invention, wherein the control unit performs an operation for stopping the current supply when the second switch is turned on again after being turned on. It is in the point which becomes. And by employ | adopting such a structure, the malfunctioning of an electric power supply stop can be prevented.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an embodiment of a current supply interruption device for a printer according to the present invention. In this embodiment, a first transistor 10 driven by an input power source Vin and a second transistor driven by a logic power source Vcc are shown. And a transistor 11. The input power source Vin is a power source such as a battery or an AC adapter, and the logic power source Vcc is transformed from a DC-DC converter (not shown) via a transformer.
[0015]
The emitter E of the first transistor 10 is connected to the input power source Vin via a wiring 12, and the collector C is driven by a control unit including a DC-DC converter and a CPU and a motor via a wiring 13. It is connected to the action | operation part 14 which has a mechanism part. Further, the base B of the first transistor 10 is grounded via a resistor 22, a wiring 15, a first switch 16 for turning on the operating unit 14, and a wiring 17.
[0016]
On the other hand, the base B of the second transistor 11 is connected to the logic power supply Vcc via a wiring 18 provided with a voltage stabilizing resistor 19 and is also connected in parallel to a first port 20 described later. . The collector C of the second transistor 11 is connected to the wiring 15 from the base B of the first transistor 10 via the wiring 23. Further, the emitter E of the second transistor 11 is grounded via a wiring 24.
[0017]
The second switch 27 for turning off the operating unit 14 is connected to the logic power source Vcc through a wiring 25 provided with a voltage stabilizing resistor 26 and grounded through a wiring 28. Further, the wiring 25 branches to a second port 29 described later.
[0018]
The first switch 16 and the second switch 27 are two-pole single-throw switches that are turned on and off at the same time, and both the switches 16 and 27 are turned on only when the operator is operating. When the operator releases his hands from both switches 16 and 27, the operator immediately turns off the switch.
[0019]
The first port 20 and the second port 29 are set to take one of two values “1” and “0”, respectively. Among these, when the first port 20 takes the value “1”, the current from the logic power source Vcc flows from the first port 20 to the base B of the second transistor 11, and thus both transistors 10 and 11 are turned ON. Will be. When the first port 20 takes the value “0”, the current from the first port 20 to the base B of the second transistor 11 is cut off, so that both the transistors 10 and 11 are turned off. . On the other hand, the second port 29 is set to take a value “0” when both the switches 16 and 27 are turned on and take a value “1” when both the switches 16 and 27 are turned off. By detecting that the second switch 27 is ON, the current to the operating unit is cut off.
[0020]
Next, the operation of the above-described embodiment will be described.
[0021]
First, ON Then the manual operation of both switches 16 and 27 of the 2 pole single-stage for turning on the power, since the first switch 16 of this is turned ON, the wire current from the input power supply V in is 12 , 15 to the first switch 16. At this time, since a current flows through the base B of the first transistor 10, the first transistor 10 is turned on, and a current from the input power source Vin flows from the emitter E to the collector C of the first transistor 10. Through the control unit including the DC-DC converter and the CPU and the operation unit 14 having the mechanism unit driven by the motor, and the CPU is turned on.
[0022]
Then, initialization is performed by the CPU, and the first port 20 takes the value “1”. Then, current flows from the first port 20 to the base B of the second transistor 11 to turn on the second transistor 11, and the current of the logic power source Vcc flows from the wiring 21 to the emitter E from the collector C of the second transistor 11. become. A part of this current also flows to the base B of the first transistor 10 via the wirings 23 and 15, so that the first transistor 10 is maintained in the ON state. Therefore, even if the hand is released from the first switch 16 and the first switch 16 is turned off, the current is continuously supplied to the operating unit 14. In order to stably supply current to the operating unit 14 so that the second transistor 11 is turned on before the first switch 16 is turned off, the CPU of the operating unit 14 When turned ON, the first port 20 immediately takes the value “1” according to the initial value of the CPU.
[0023]
Next, the operation when the power is turned off will be described.
[0024]
When the second switch 27 is turned on when the power is turned on, the second port 29 once takes the value “0”. Then, when the second switch 27 is turned off, the second port 29 again has the value “0”. 1 ”, the CPU of the operation unit 14 stores the change in the value of the second port 29. Then, since the second switch 27 when the power shutoff is turned ON, the second port 29 takes again the value "0", the CPU, the value of the second port 29 is "0" - "1" - " By satisfying “0”, the first port 20 is ready to take the value “0”. At this time, the CPU determines whether or not the printer job such as paper discharge remains, and if the job remains, the first port 20 takes the value “0” after the job is completed.
[0025]
As described above, when the first port 20 takes the value “0”, the first port 20 stops supplying the current to the base B of the second transistor 11. Then, the second transistor 11 is turned off. As a result, the supply of current to the base B of the first transistor 10 is also cut off, so that the first transistor 10 is also turned off, Supply from the input power source Vin is interrupted.
[0026]
As described above, in the present embodiment, the supply of power to all parts of the operation unit 14 is stopped when the power is shut down, so that the power consumption is small and the invention can be applied to a battery-driven printer.
[0027]
Further, when the work as a printer remains when the power is shut off, the power is shut off after the remaining work is finished, so there is no possibility that the work is interrupted in the middle. On the other hand, when the power is shut off, the shut-off operation is started only when the value of the second port 29 satisfies “0” − “1” − “0”, so there is no possibility of malfunction of the power shut-off.
[0028]
Furthermore, since the first switch 16 and the second switch 27 are two-pole single-throw switches that are turned ON / OFF synchronously, the configuration of the switches can be simplified.
[0029]
In addition, from the above, the whole can be simplified, downsized, and manufactured at a lower cost.
In addition, this invention is not limited to embodiment mentioned above, A various change is possible as needed.
[0030]
【The invention's effect】
As described above, according to the current supply interruption device for a printer according to the present invention, it is possible not only to reduce the size, but also to reduce power consumption, and to stop after completely discharging paper. In addition, it can be manufactured at low cost.
[0031]
That is, the first transistor for supplying the current of the power source to the operating unit, the second transistor for continuing the ON state of the first transistor, and the first transistor for synchronously controlling ON / OFF of the both transistors. A port, a first switch that activates the first transistor, a second switch that cuts off current to the operating unit, and the second switch are turned on. A second port for detection, and when the control unit has turned on both the switches and cuts off the current, if the work as a printer remains, the control unit uses the first port after finishing the work. Since both the transistors are turned off, the remaining work as a printer, such as paper discharge, is completed and then stopped. Can not only, at the time of stop, since power to the control unit is not supplied, power consumption can be reduced.
[0032]
In addition, if the first switch and the second switch are two-pole single-throw switches that are turned ON / OFF synchronously with each other, the switches can be configured simply.
[0033]
Furthermore, if the control unit performs an operation for stopping the current supply when the second switch is turned on again after being turned on, the malfunction of the power supply stop can be prevented.
[Brief description of the drawings]
FIG. 1 is an electric circuit diagram showing an embodiment of a printer current supply cutoff device according to the present invention. FIG. 2 is an electric circuit diagram showing an example of a conventional printer current supply cutoff device. FIG. Electrical circuit diagram showing another example of the supply cutoff device
DESCRIPTION OF SYMBOLS 1 Power supply 2 Switch 3 Operation | movement part 4 Control part 5 Mechanism part 6 Switch 10 1st transistor 11 2nd transistor 14 Operation | movement part 16 1st switch 20 1st port 27 2nd switch 29 2nd port Vin Input power supply Vcc Logic power supply

Claims (3)

A printer current supply cutoff device that supplies and cuts off current to various operation units including a printer control unit,
A first transistor for supplying a current of a power source to the operating unit;
A second transistor for continuing the ON state of the first transistor;
A first port for controlling ON / OFF of both transistors synchronously;
A first switch that activates the first transistor and a second switch that cuts off the current to the operating unit;
A second port for detecting that the second switch is ON,
The control unit is configured to turn off both transistors by the first port after finishing the work if the work as a printer remains when the switches are turned on to cut off the current. An apparatus for interrupting current supply for a printer. 2. The printer current supply cutoff device according to claim 1, wherein the first switch and the second switch are two-pole single-throw switches that are turned on and off in synchronization with each other. 3. The control unit according to claim 1, wherein the controller is configured to perform an operation for stopping current supply when the second switch is turned on again from ON to OFF. 4. The current supply cutoff device for a printer according to the description.

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