JP2560886B2 - Remote control device drive circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a remote control relay (hereinafter referred to as a remote control relay) and a remote control circuit breaker (hereinafter referred to as a remote control breaker) used for a distribution board or the like. ) And other remote control devices for on / off control of the control device drive circuit.

[Prior Art] FIG. 6 is a circuit diagram showing a remote control relay (1) and a conventional drive circuit (2) thereof. In the figure, a remote control relay (1) and a drive circuit (2) are connected so as to form a closed circuit including a power supply (3). As the power source (3), for example, a 24V AC power source is used. When the ON control signal (22) of the remote control relay (1) is output from the control circuit (21), the ON control contact (23) is closed in conjunction with this.
The ON control signal (22) is a one-shot signal in order not to cause hunting of the remote control relay (1) and, for example, issues an ON signal for about 100 msec. The diode (24) passes only a half wave of the alternating current of the power supply (3). This passed current (4) passes through the diode (11) of the remote control relay (1) and contacts (12).
Flows through the closed circuit to the coil (13). The coil (13) is excited by this current (4) and the main contact (14)
Close the circuit and switch the contact (12) to the terminal (12b) side. As a result, the current (4) flowing through the coil (13) is cut off. From this point onward, the circuit is disconnected, and the current (4) does not flow. On the other hand, the main contact (14) is mechanically latched and kept in the ON state, and the load (not shown) connected thereto is supplied with power from another power supply (not shown).

Next, when the control circuit (21) outputs the OFF control signal (25) of the remote control relay (1), the OFF control contact (26) is closed in conjunction with this. The off control signal (25) is also a one-shot signal like the on control signal (22). The diode (27) allows a half-wave of the alternating current of the power source (3) having a phase opposite to that of the diode (24) described above to pass therethrough. In this case, the coil (1
3), the contact (12) and the diode (15), and the current (5) flows through the diode (27) and the OFF control contact (26). This current (5) causes the coil (13)
Excites the main contact (14) by being excited to the opposite polarity to the excitation by the current (4) and switches the contact (12) to the terminal (12a) side. This interrupts the current (5). From this point onward, the circuit is disconnected so that the current (5) does not flow. On the other hand, the main contact (14) is mechanically latched and kept in the off state, and the load connected thereto is turned off.

The above operation will be described with reference to the signal waveforms in FIG. FIG. 7A shows an AC voltage waveform of the power supply (3). Next (b)
Is a signal waveform of the ON control contact (23), in which a high level is turned on (closed) and a low level is turned off (open). When the signal waveform (b) of the on-control contact (23) is on, the current (4) flows when the alternating voltage waveform (a) becomes a high voltage on the positive side. This waveform is shown in (c). Since the remote control relay (1) operates sufficiently with one half-wave, the current (4) is cut off when the contact (12) is switched to the terminal (12b) side by the operation, and the waveform (C) The trailing edge is missing in the waveform. (D) is a signal waveform of the off control contact (26). In this case as well, the operation is the same as the operation of the ON control contact (23), but the waveform (e) of the current (5) has a phase opposite to that of the waveform (c).

[Problems to be Solved by the Invention] In the conventional remote control device drive circuit, the ON control contact (23) and the OFF control contact (26) are turned on / off regardless of the phase of the power supply (3). Depending on the phase, as in the waveform shown in FIG. 7 (f), it was not driven by the half-wave electric energy of the first mountain but was driven by the half-wave electric energy of the second mountain. Depending on the phase, there is a case where the remote control relay (1) can barely be turned on or off while the electric energy is small as shown in the waveform of FIG. 7 (g). However, in this case, the internal lever may be returned from the on state to the off state due to the mechanical characteristics of the remote control relay (1), so the lever is turned on again but turned off again, and the on control cannot be completed completely. There was no problem. Also, relay contacts (23,26) to the drive
However, there is a problem that the operating time is long and the contact life is short due to the use of.

The present invention has been made to solve the above problems, and provides a remote control device drive circuit that can reliably perform on / off drive of a remote control relay or the like and has a short operating time and a long life. The purpose is to do.

[Means for Solving the Problem] The present invention relates to a remote control device drive that should form a part of a closed loop including an AC power supply and a remote control device that changes its on / off state according to the direction of current flow. In the circuit, zero-cross detection means for detecting the near zero-cross of the AC power supply, and when the zero-cross detection means is detecting near the zero-cross, it is in the forward direction with respect to the phase of the AC power supply and of the remote control device. When the first switch means for closing the closed loop in one direction by receiving an on-control signal and the zero-cross detection means detect the vicinity of the zero-cross, it is in the forward direction with respect to the phase of the AC power supply. And a second switch means for closing the closed loop in the other direction by receiving a signal for turning off the remote control device. The first switch means and the second switch means are a combination of a photothyristor fired by the ON control signal or the OFF control signal and a thyristor fired by the operation of the photothyristor. It is a feature. Further, as display means, the display means is provided in parallel with the first and second switch means,
A first direction in which the one direction and the other direction are forward directions, respectively.
The light emitting diode and the second light emitting diode may be provided. Further, as means for supplying a signal used for monitoring or the like to the outside, a first photocoupler and a second photocoupler connected in series to the first light emitting diode and the second light emitting diode, respectively, are used. It may be provided.

[Operation] The first switch means and the second switch means in the present invention receive the ON control signal and the OFF control signal respectively when the vicinity of the zero cross of the AC power supply is detected by the zero cross detection means, The closed loop formed with the remote control device is closed in a predetermined direction.

The first light emitting diode and the second light emitting diode indicate an on / off state of the remote control device, and the first photocoupler and the second photocoupler send a signal according to the on / off state to the outside. To do.

[Embodiment] FIG. 1 is a circuit diagram including a remote control device drive circuit according to the first embodiment. FIG. 2 is a graph showing a signal waveform in the main part of FIG. In FIG. 1, a remote control device drive circuit (30) is connected via its terminals (101, 102) to a remote control relay (1) and a power supply (3) to form a closed circuit. The remote control relay (1), the power supply (3) and the control circuit (21) are the same as the conventional ones. A photocoupler (103) connected between terminals (101) and (102) via a resistor (104) for limiting current,
Operates with bidirectional input. That is, the sine wave waveform of the power source (3) conducts in both positive and negative polarities, and becomes non-conductive near the zero cross due to the forward voltage of the diode on the input side of the photocoupler (103). Photocoupler (103)
When current flows to the input side of the
b) is turned on, no current flows through the base of the transistor (105) connected to its collector, and the transistor (10
5) is turned off. Next, when the current on the input side of the photocoupler (103) stops, the transistor (103b) on the output side also turns off, and the resistor (106) is added to the base of the transistor (105).
A current flows through the transistor (105) and the transistor (105) is turned on. This operation will be described with reference to FIG. (A) is the voltage waveform of the power supply (3), and (b) is the output waveform of the transistor (105). The transistor (105) turns on only in the vicinity of the zero cross of the voltage waveform (a), and turns off in the other portion. In FIG. 1 again, the on-control signal (22) is electrically low level.
When this signal is input as shown in FIG. 2 (c), the diode (107a) of the photothyristor (107) is biased in the forward direction. At this time, when the transistor (105) is in the ON state and the power supply voltage waveform (a) is in the positive direction, a current flows through the diode (107a) and the photothyristor (10
7) Thyristor (107b) is fired. This allows
The thyristor (107b) becomes conductive, the gate of the next connected thyristor (108) is fired, and similarly the thyristor (108) becomes conductive. As a result, a current (4) flows and the remote control relay (1) is turned on.

When the remote control relay (1) is turned on and maintains its state, the internal contact (12) is switched to the terminal (12b) side to disconnect the circuit. Therefore, the thyristor (108) becomes non-conductive. The waveform of the current (4) during this period is as shown in FIG. In this state, from the power supply (3) to the coil (13), the contact (12) terminal (12b),
A closed circuit that returns to the power supply (3) through the diode (15), the terminal (102), the resistor (111), the red light emitting diode (122), and the terminal (101) is formed, and current flows. In this case, the resistor (111) selects a resistor that suppresses the current flowing through the coil (13) to a level at which the coil (13) is excited and the contact (14) does not operate. Since the light emitting diode (122) emits light by this current, it can be displayed that the remote control relay (1) is in the ON state.

Next, when the OFF control signal (25) is input as shown in FIG. 2 (e), the diode (1) of the photothyristor (109) is
09a) is forward biased. At this time, when the transistor (105) is on and the power supply voltage waveform (a) is in the negative direction, a current flows through the diode (109a) and the thyristor (109b) of the photothyristor (109) is ignited. As a result, the thyristor (109b) becomes conductive, and the gate of the next connected thyristor (110) is fired to become conductive. As a result, a current (5) flows to operate the remote control relay (1) to the off state.
When the remote control relay (1) operates, the contact (12) is switched to stop the circuit from conducting, and the thyristor (110) also stops conducting, as described above. The waveform of the power supply (5) during this period is as shown in FIG.

When the remote control relay (1) is turned off and held in that state, the thyristors (108) and (110) are both non-conductive. In this state, connect the power supply (3) to the terminal (10
1), a green light emitting diode (121), a resistor (111), a terminal (102), and a remote control relay (1) to form a closed circuit that returns to the power supply (3), and a current flows. This current causes the light emitting diode (121) to emit light, so that it can be displayed that the remote control relay (1) is in the off state.

In the above circuit, when the power supply (3) fails, or the contact (12) is not fully operational, the terminals (12a) and (12)
If you do not switch to any of b) or if the wiring between the remote control relay (1) and the remote control device drive circuit (30) is disconnected, the current loop will be disconnected,
None of the light emitting diodes (121, 122) emits light. Since this can be identified as an abnormal condition, the control circuit (21)
Can perform processing such as determining an abnormality and issuing an alarm.

The thyristors (108) and (110) become non-conductive when the anode and the cathode are reversely biased, and do not become conductive until they are ignited thereafter. However, even if the remote control relay (1) does not operate with one half-wave and one mountain, if the ON control signal (22) and the OFF control signal (25) are sufficiently long, they will be fired again in the next AC cycle and become conductive. Therefore, the operation for conduction can be repeated while the signals (22) and (25) are maintained.

Although the remote control relay is used as the control target in the above embodiment, a remote control breaker can be driven by a similar circuit without any problem.

FIG. 3 is a circuit diagram showing the second embodiment. The thyristors (108, 110) and resistors around them are removed from the first embodiment. In the first embodiment described above, the circuit configuration in which the thyristors (108) and (110) are ignited by the photothyristors (107) and (109), respectively, is shown in FIG. If (107A, 109A) is used, the thyristor (108, 110) used in the first embodiment is unnecessary, and the remote control relay (1) etc. can be directly driven by these photothyristors (107A, 109A). .

FIG. 4 is a circuit diagram showing the third embodiment. The difference from the first embodiment is that the photocoupler (11) that operates by the currents flowing in the light emitting diodes (121) and (122), respectively.
5) and (112) are provided so that a signal indicating the on / off state of the remote control relay (1) can be sent to an external circuit.

When the ON control signal (22) is input and, as a result, the remote control relay (1) operates and maintains its state, as in the first embodiment, the internal contact (12) moves to the terminal (12b) side. The circuit is disconnected by switching to. Although the thyristors (108) and (110) are both non-conductive in this state, the coil (13) from the power supply (3), the terminal (12b) of the contact (12), the diode (15), the terminal (102), and the resistor. Bowl (11
1), the diode (112a), the light emitting diode (122), and the terminal (101) to form a closed circuit that returns to the power supply (3), and a current flows. Due to this current, the light emitting diode (122) emits light to indicate the ON state of the remote control relay (1), but the resistor (111) has a predetermined resistance value, so that the coil (13) is sufficiently charged. The current is not so high as to be excited, and therefore the contact (14) does not operate. Also,
This current causes the photocoupler (112) transistor (1
12b) becomes conductive and sends the signal (114) to the outside through the resistor (113). When this signal is at a high level, it indicates that the remote control relay (1) is on, so that the control circuit (21) can read this signal for monitoring and the like.

When the OFF control signal (25) is input and, as a result, the remote control relay (1) operates and maintains its state, as in the first embodiment, the internal contact (12) is moved to the terminal (12a) side. The circuit is disconnected by switching to. Although the thyristors (108) and (110) are both non-conductive in this state, they are connected to the terminal (101) from the power source (3) to the light emitting diode (12).
1), diode (115a) of photocoupler (115), resistor (111), terminal (102), diode (11), contact (1
Power supply (3) through terminal (12a) and coil (13) of 2)
A closed circuit is formed back to and current flows. Due to this current, the light emitting diode (121) emits light to indicate the off state of the remote control relay (1), but the resistor (111) has a predetermined resistance value, so that the coil (13) can be sufficiently operated. It does not generate enough current to excite, and therefore the contact (14)
Does not work. In addition, the photocoupler (11
The transistor (115b) of 5) becomes conductive and sends the signal (117) to the outside through the resistor (116). Since this signal indicates that the remote control relay (1) is off when it is at a high level, the control circuit (21) can read this signal for monitoring and the like.

FIG. 5 is a circuit diagram showing the fourth embodiment. The difference from the second embodiment is that the photocoupler (11) that operates by the currents flowing in the light emitting diodes (121) and (122) respectively.
5) and (112) are provided so that a signal indicating the on / off state of the remote control relay (1) can be sent to an external circuit. The operation of the photocouplers (115) and (112) is the same as that of the third embodiment, and therefore its explanation is omitted.

[Effects of the Invention] Since the present invention is configured as described above, it has the effects described below.

In the remote control device drive circuit according to claim (1), the ON control signal or the OFF control signal of the remote control device is accepted on condition that the AC power supply is in the vicinity of zero crossing, whereby the photothyristor and the thyristor are connected. Since the circuit structure for igniting the combined switch means is adopted, the ignition of the switch means is started in synchronization with the zero cross of the AC power supply. Therefore, there is an effect that a current having a desired half-wave waveform can be always supplied to the remote control device in synchronization with the phase of the AC power supply, and the remote control device can always be operated reliably. Further, since all the driving circuits are made of a semiconductor, there is an effect that the operation time can be shortened and the life can be extended.

In the remote control device drive circuit according to claim (2), the on / off state of the remote control device can be further displayed.

In the remote control device drive circuit according to claim (3), a signal indicating the ON / OFF state of the remote control device can be sent to the outside for monitoring or the like.

[Brief description of drawings]

FIG. 1 shows a remote control device drive circuit (3 according to the first embodiment.
0) and its peripheral circuits, FIG. 2 is a graph showing the signal waveform of each part of FIG. 1, and FIG. 3 shows the remote control device drive circuit (31) and its peripheral circuits according to the second embodiment. Figure showing,
FIG. 4 shows a remote control device drive circuit (3
2) and a peripheral circuit thereof, FIG. 5 is a diagram showing a remote control device drive circuit (33) according to the fourth embodiment and its peripheral circuit, and FIG. 6 is a conventional remote control device drive circuit and its periphery. FIG. 7 is a graph showing a circuit, and FIG. 7 is a graph showing a signal waveform of each portion of FIG. In the figure, (1) is a remote control relay, (3) is an AC power supply, (22) is an ON control signal, (25) is an OFF control signal, (30 to 33) are remote control device drive circuits, and (103). Is a photocoupler, (105) is a transistor, (107,109) is a photothyristor, (108,110) is a thyristor, and (112,11)
5) is a photocoupler, and (121,122) is a light emitting diode. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (3)

(57) [Claims] 1. A remote control device drive circuit that should form a part of a closed loop including an AC power supply and a remote control device that changes its on / off state in accordance with the direction of current flow. By means of a zero-cross detecting means for detecting the vicinity, and when the zero-cross detecting means is detecting the vicinity of the zero-cross, it is in a forward direction with respect to the phase of the AC power supply and receives an ON control signal for the remote control device. When the first switch means for closing the closed loop in one direction and the zero-cross detection means detect the vicinity of the zero-cross, it is in the forward direction with respect to the phase of the AC power supply and the OFF control of the remote control device is performed. A second switch means for closing the closed loop in the other direction by receiving a use signal, and the first switch means and the first switch means The switch means is a combination of a photothyristor ignited by the ON control signal or the OFF control signal and a thyristor ignited by the operation of the photothyristor. . 2. A first light emitting diode and a second light emitting diode which are provided in parallel with the first and second switch means and which have the one direction and the other direction as forward directions, respectively. The remote control device drive circuit according to claim 1. 3. A first light emitting diode and a second light emitting diode, which are provided in parallel with the first and second switch means and have forward directions in the one direction and the other direction, respectively, and the first light emitting diode. A first photocoupler and a second photocoupler connected in series to the light emitting diode and the second light emitting diode, respectively.
3. The remote control device drive circuit according to claim 1, further comprising: