JPS588098B2 - Relay Seigiyo Cairo - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a relay control circuit, and an object of the present invention is to improve reliability and durability by maintaining the switching state of a relay using an electronic timer circuit.

1 is a power transformer, 2 is a constant voltage supply circuit, which is composed of a rectifier diode 3, a smoothing capacitor 4, a transistor 5 for controlling the constant voltage supply line to be conductive or nonconductive, a Zener diode 6, and a resistor 7; is supplied to the next downstream circuit.

8 is a first electronic timer circuit that maintains the first state of the relay circuit 9 and switches it to the second state; this timer circuit includes a charging circuit consisting of a resistor 11 and a capacitor 12; The circuit 17 and the anode A are connected to the intermediate point of the charging circuit 13, and the gate G
is semi-fixedly connected to the resistor 15 of the voltage divider circuit 17,
The cathode K is constituted by a first PNPN type controlled rectifier (hereinafter referred to as first PUT) 19 connected to the power supply side via a trigger resistor 18.

The relay circuit 9 includes a relay 20 having switching contacts b and a.
and a silicon controlled rectifier (hereinafter referred to as SCR) 21 that controls the energization of the relay are connected in series, and the gate G of the SCR 21 is connected to the trigger resistor 18.

Reference numeral 21 denotes a second electronic timer circuit which maintains the second state of the relay circuit 9 and outputs the output to a recovery circuit which will be described later, which includes a resistor 22 and a capacitor 2, similar to the first electronic timer circuit 8.
3, a voltage dividing circuit 28 consisting of resistors 25, 26, and 27, the anode A is connected to the midpoint of the charging circuit 24, and the gate G is semi-fixed to the resistor 26 of the voltage dividing circuit 28. The cathode K is connected to the second PUT 30 connected to the power supply side via the trigger resistor 29.
It is composed of

Reference numeral 31 denotes a return circuit that turns off the transistor 5, cuts off the voltage supply to the relay 20, and returns the second state to the first state; the return circuit connects the anode A to the base of the transistor 5; Connect the gate G to the trigger resistor 20 of the second PUT 30, and connect the cathode K
It has an SCR 32 connected to the power supply side.

Next, the operation will be explained.

When voltage is applied to the first electronic timer circuit 8 from the constant voltage supply circuit 2, the capacitor 12 of the charging circuit 13 becomes the resistor 11.
charged with time constant T1=R1C1 through the first PUT
When the anode voltage (A) of the first PUT 19 becomes approximately equal to the gate voltage (G), the first PUT 19 becomes conductive and connects to the cathode, or generates a pulse voltage in the trigger resistor 18.

This voltage is supplied to the gate of the SCR 21, and the SCR becomes conductive, and the relay 20 also becomes conductive, and its contact C switches from the b side, which maintains the first state, to the a side, which maintains the second state.

At the same time as the relay 20 becomes conductive, the second electronic timer circuit 2
The charging circuit 24 of No. 1 is also charged with a time constant T2-R2C2, and when the anode voltage of the second PUT 30 becomes almost equal to the gate voltage, the second PUT 30 becomes conductive and a pulse-like voltage is generated in the trigger resistor 29 connected to the cathode. .

This pulsed! Voltage is applied to the gate of the SCR 32 of the recovery circuit 31, the SCR 32 becomes conductive, the base voltage of the transistor 5 decreases, and the transistor 5 is turned off.

Therefore, the collector and emitter of the transistor 5 become non-conductive, and the constant voltage supply line to the first and second electronic timer circuits 821 and the relay circuit 9 becomes non-conductive.

Therefore, the first PUT 19 of the first electronic timer circuit 8 is de-energized, and the SCR 21 is also de-energized.

Further, since the constant voltage supply to the relay circuit 9 is cut off, the voltage applied to both ends of the relay 20 becomes zero, and the relay 20
The contact point C switches from side a, which holds the second state, to side b, which holds the first state.

On the other hand, the second PUT 30 of the second electronic timer circuit 21 becomes non-conductive, and the SCR 32 also becomes non-conductive.

Therefore, the transistor 5 of the constant voltage supply circuit 2 is turned ON again.
However, a constant voltage is supplied to the first and second electronic timer circuits 8 and 21 and the relay circuit 9.

Figure 2 shows the time chart of the relay, where the first state is held between T1-T1C1 and the second state is T2-R.
It is held only for 2C2.

As described above, the relay control circuit according to the present invention includes a constant voltage supply circuit including a transistor that controls the constant voltage supply line to be conductive or nonconductive, and a first electronic timer that maintains the first state of the relay and switches it to the second state. A second electronic timer circuit that maintains the second state and outputs the output to the return circuit, and a return circuit that returns the second state to the first state by the final stage output of the circuit. Relay switching and holding operations are performed reliably.

In addition, there is no need to connect a reset circuit, etc. consisting of a relay and relay contacts, which can cause failures such as welding of contacts, to the first and second electronic timer circuits and the reset circuit.
This simplifies the circuit, improves reliability and durability, and has practical effects.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram of a relay control circuit according to the present invention, and FIG. 2 is a time chart showing the switching operation of the relay. 2... Constant voltage supply circuit, 8... First electronic timer circuit,
9... Relay circuit, 21... Second electronic timer circuit, 3
1...Return circuit.

Claims (1)

[Claims] 1. A constant voltage supply circuit including a transistor that controls the constant voltage supply line to be conductive or nonconductive, a first electronic timer circuit including a first PUT that maintains the first state of the relay and switches it to the second state, and the relay. a second electronic timer circuit including a second PUT that maintains the second bark state and outputs the output to the return circuit; and a second electronic timer circuit that is operated by the output and turns off the transistor to return the second state to the first state. A relay control circuit characterized by comprising a return circuit and a return circuit.