KR100257392B1 - Hold function type piezoelectric elevator switch. - Google Patents

Abstract

PURPOSE: A hold function type piezoelectric elevator switch is provided to recognize the pushing state of a switch by integrating two piezoelectric elements having opposite polarity into one device, thus performing a switch hold function. CONSTITUTION: A piezoelectric device(22) having first/second piezoelectric elements(a,b) is attached to an instrument panel unit(21). A resistor(R6) is connected between the first piezoelectric element(a) and a node(N5). A resistor(R7) is connected between the node(N5) and a ground voltage(Vss). An NMOS transistor(Q3) is connected between a source voltage(Vcc) and a node(N6), and its gate is connected to the node(N5). A resistor(R8) is connected between the node(N6) and ground voltage(Vss). An R-S flip-flop(23) inputs set signal and reset signal to the nodes(N6,N8). A controller(24) detects the normal output signal(N9) of the R-S flip-flop(23) to discriminate whether an elevator switch is pushed.

Description

Piezoelectric Elevator Switch Circuit with Hold Function

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric elevator switch circuit capable of a hold function. In particular, a piezoelectric element having an opposite characteristic is integrated to recognize a state when a switch is pressed and released, and also a switch hold function. The present invention relates to a piezoelectric elevator switch circuit that automatically returns even when an elevator door is not closed.

1 is a circuit configuration diagram of a piezoelectric elevator switch according to the prior art, which is switched by an operation of the instrument panel portion 11 on which a piezoelectric body 12 is mounted and the piezoelectric body 12 to output a first logic value. When the first logic value is outputted from the switching circuit units Q1 and R1 to R3 and the switching circuit unit, it is determined that the elevator switch is pressed and the second logic value and the third logic value are respectively determined as the first and second output terminals. The control unit 13 for outputting, and when the second logic value is outputted from the second output terminal, the switch when driving the LED to inform the user that the elevator switch is selected is composed of an LED driver (14).

First, when a user presses a portion of the piezoelectric body 12 that is requested to the instrument panel unit 11 to select the operation of the elevator, a square wave signal is generated to the node N1 to operate the switching element Q1. This switching element Q1 is an NMOS transistor, which is turned on to bring the potential of the node N2 to the ground potential Vss.

At this time, when the potential of the node N2 becomes 'low' level, the control unit 13 determines that the switch is pressed, and outputs a signal of a predetermined potential to the node N3 to notify that the specific layer is selected, and also the node ( The LED driver 14 is operated by outputting 'high' to N4).

The LED driver 14 operates when the potential of the node N4 is 'high' to turn on the LED to inform the user that a switch is selected.

By the way, in the conventional piezoelectric elevator switch configured as described above, there is a problem that a malfunction occurs because it is configured to generate a voltage only when the user presses the piezoelectric body. That is, the conventional piezoelectric elevator generates an instantaneous sine wave signal only at the moment when the piezoelectric element is energized, and the switching element is operated by this signal to generate a constant logic value and to determine the generated logic signal. Will be detected. Therefore, it is impossible to recognize when the switch is kept pressed, there was a problem that the elevator door does not close due to malfunction when releasing the switch.

Accordingly, the present invention has been made to solve the above problems, an object of the present invention is to integrate the piezoelectric body having the opposite characteristics to recognize the state when the switch is pressed and when the switch can hold the function, The present invention provides a piezoelectric elevator switch circuit capable of holding a function that can automatically return even when the elevator door is not closed due to a malfunction.

1 is a circuit diagram of a piezoelectric elevator switch according to the prior art

Figure 2 is a circuit diagram of a piezoelectric elevator switch according to an embodiment of the present invention

Explanation of symbols on the main parts of the drawings

11, 21: Instrument panel part in which piezoelectric element is mounted

12, 22: piezoelectric element 13, 24: control unit

14, 25: LED driver 23: R-S flip-flop

26: switch hold operation release signal generator

In order to achieve the above object, a piezoelectric elevator switch circuit having a hold function according to the present invention includes a mechanism panel means to which piezoelectric bodies are formed by integrating first and second piezoelectric bodies having opposite characteristics;

First switching means for switching by the operation of the first piezoelectric element and outputting a first logic value;

Second switching means for operating opposite to the first switching means by an operation of the second piezoelectric body to output a second logic value;

R-S flip-flop means for inputting said first logic value as a first input signal and said second logic value as a second input signal, respectively;

Control means for detecting a normal output signal of the R-S flip-flop means and outputting a signal determined that the elevator switch is pressed;

LED driving means for driving the LED to inform the user that the elevator switch is selected by the output signal of the control means;

Switch-hold operation release signal generating means for temporarily charging the normal output voltage of the R-S flip-flop means and using the second input signal;

And a switch hold operation release signal reset means for switching by the first input signal to discharge the voltage charged in the switch hold operation release signal generating means to a ground voltage.

Here, the first and second switching means are each composed of a MOS transistor and a resistor, and the MOS transistor is preferably an NMOS.

Preferably, the switch hold operation release signal generating means is composed of a resistor and a capacitor connected in series between the output terminal of the RS flip-flop means and a ground voltage, and the switch hold operation release signal reset means is composed of a bipolar transistor. .

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a circuit diagram of a piezoelectric elevator switch according to an embodiment of the present invention, and includes a mechanism panel in which piezoelectric bodies 22 incorporating first and second piezoelectric bodies a and b having opposite characteristics are integrated. Means (21), a resistor (R6) connected between the first piezoelectric body (a) and the node (N5), a resistor (R7) connected between the node (N5) and a ground voltage (Vss), An NMOS transistor Q3 connected between a power supply voltage Vcc and a node N6 and a gate connected to the node N5, and a resistor R8 connected between the node N6 and a ground voltage Vss. It consists of.

The NMOS transistor Q3 switches according to the potential of the node N5 to supply a power supply potential Vcc or a ground potential Vss to the node N6.

In addition, a resistor R9 connected between the second piezoelectric body b and the node N7, a resistor R10 connected between the node N7 and the ground voltage Vss, and a power supply voltage Vcc. And an NMOS transistor Q4 connected between the node N8 and a gate connected to the node N7, and a resistor R11 connected between the node N8 and the ground voltage Vss.

The NMOS transistor Q4 switches according to the potential of the node N7 to supply the power potential Vcc or the ground potential Vss to the node N8.

In addition, the present invention provides an RS flip-flop 23 for inputting the node N6 and the node N8 as a set signal and a reset signal, respectively, and a normal output signal of the RS flip-flop 23. The controller 24 detects (N9) and outputs a signal indicating that the elevator switch is pressed to the nodes N10 and N11, and a signal of the node N11 output from the controller 24 causes the user to receive the signal. It is provided with an LED driver 25 for driving the LED to indicate that the elevator switch has been selected.

The LED driver 25 includes a resistor R14 connected to the node N11, an NPN bipolar transistor Q6 having one terminal of the resistor R14 connected to a base and an emitter connected to ground, An LED diode connected with the collector and the cathode of the NPN type bipolar transistor Q6 is connected, and a resistor R13 connected between the anode of the LED diode and the power supply voltage Vcc.

In addition, the present invention provides a switch hold operation release signal generator 26 which temporarily charges the normal output voltage N9 of the RS flip-flop 23 to use the second input signal R, and the first input signal. A switch hold operation release signal reset unit Q5, which is switched by (S) and discharges the voltage charged in the switch hold operation release signal generation unit 26 to the ground voltage, was added.

The switch hold operation release signal generator 26 charges the capacitor C1 through the resistor R12 even when the user releases the hand while the switch is pressed, that is, the piezoelectric body b does not operate. When the charged voltage becomes higher than a predetermined value, the normal output signal N9 of the flip-flop 23 is made low by automatically applying 'high' to the reset (R) signal of the flip-flop 23. The held switch will be released.

The switch hold operation release signal reset unit Q5 is for extending the off time of the automatic switch.

That is, as soon as the user presses the piezoelectric switch again, the set signal S of the flip-flop 23 becomes 'high', and the transistor Q5 is turned on when the set signal S becomes 'high'. By discharging the voltage charged in the capacitor C1 of the switch hold operation release signal generator 26 to the ground potential, the switch hold operation release signal is increased to the maximum value.

The operation by the above configuration will be described.

First, when the user presses the instrument panel 21 to which the piezoelectric body 22 is attached, a 'high' logic signal is generated at the node N5 and a 'low' logic signal is generated at the node N7. Accordingly, the first switch element Q1 is turned on, the second switch element Q2 is turned off, 'high' is input to the set S terminal of the flip-flop 23, and the reset ( 'Low' is input to the R) terminal, and the normal output signal N9 of the flip-flop 23 becomes 'high'.

In this case, when the output signal from the flip-flop 23 is recognized as 'high', the controller 24 generates a signal indicating that a specific layer is selected to the host side through the node N10, and the node N11. By turning on the LED driver 25 to inform the user that the switch is selected, the switch hold function.

That is, in this state, the open operation switch of the elevator is kept pressed while the output signal Q of the flip-flop 23 is 'high', so the user can select the switch hold function even with the piezoelectric switch. This is possible. When the user releases the hand holding the instrument panel 21, the node N5 becomes 'low' and the node N7 becomes 'high' as opposed to the pressing. Is turned off, the second switching element Q4 is turned on so that the set signal S of the flip-flop 23 is 'low' and the reset signal R is 'high' so that the output signal Q ) Becomes low.

Meanwhile, when the normal output signal Q of the flip-flop 23 is recognized as the 'low' state, the controller 24 generates a signal indicating that the open switch selected through the node N10 is released. Then, after closing the door of the elevator on the host side, the next operation is performed. The switch-hold function is possible by integrating the piezoelectric bodies (a, b), which have the opposite characteristics of pressing and releasing.

As described above, according to the piezoelectric elevator switch circuit capable of the hold function of the present invention, the piezoelectric element having the opposite characteristic is integrated to recognize the state of pressing and releasing the switch so that the switch holding function is possible. Even if the elevator door does not close due to a malfunction, there is a very good effect that can be automatically returned.

In addition, preferred embodiments of the present invention are disclosed for the purpose of illustration, those skilled in the art will be able to various modifications, changes, additions, etc. within the spirit and scope of the present invention, these modifications and changes should be seen as belonging to the following claims. something to do.

Claims (6)

In a piezoelectric elevator switch circuit, A mechanism panel means on which piezoelectric bodies are formed by integrating first and second piezoelectric bodies having opposite characteristics; First switching means for switching by the operation of the first piezoelectric element and outputting a first logic value; Second switching means for operating opposite to the first switching means by an operation of the second piezoelectric body to output a second logic value; R-S flip-flop means for inputting said first logic value as a first input signal and said second logic value as a second input signal, respectively; Control means for detecting a normal output signal of the R-S flip-flop means and outputting a signal determined that the elevator switch is pressed; LED driving means for driving the LED to inform the user that the elevator switch is selected by the output signal of the control means; Switch-hold operation release signal generating means for temporarily charging the normal output voltage of the R-S flip-flop means and using the second input signal; And a switch hold operation release signal reset means for switching by the first input signal to discharge the voltage charged in the switch hold operation release signal generating means to a ground voltage. Circuit. 2. The piezoelectric elevator switch circuit as claimed in claim 1, wherein the first and second switching means each comprise a MOS transistor and a resistor. 3. The piezoelectric elevator switch circuit according to claim 2, wherein the MOS transistor is an NMOS. The piezoelectric elevator switch circuit according to claim 1, wherein said switch hold operation release signal generating means comprises a resistor and a capacitor connected in series between an output terminal of said R-S flip-flop means and a ground voltage. The piezoelectric elevator switch circuit having a hold function according to claim 1, wherein said switch hold operation release signal reset means comprises a bipolar transistor. The piezoelectric elevator switch circuit according to claim 5, wherein the bipolar transistor is an NPN transistor.

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