SU1583989A1 - Bistable electromagnetic relay with control circuit - Google Patents

Abstract

The invention relates to electrical engineering, specifically to relay control, and can be used, in particular, in automation and telegraphy. The purpose of the invention is to reduce power consumption and increase reliability. The device contains a relay coil 1, a capacitor 2, a diode 3, three transistors 4.1 ... 4.3, five resistors 5.1 ... 5.5 and a zener diode. When the control voltage is turned on at the moment when the voltage of the stabilization of the Zener diode 6 is exceeded, a current is applied through it and the resistors 5.4, 5.5 to the base of the transistor 4.3. Transistor 4.3 is unlocked. In this case, the relay operates due to the current flowing through the capacitor 2. The reverse switching of the relay is carried out due to the energy accumulated in the capacitor 2 through the transistor 4.1. 1 il.

Description

The invention relates to electrical engineering, specifically to relay controls and can be used, in particular, in automation and telegraphy.

The purpose of the invention is to reduce power consumption and increase reliability.

The drawing shows a diagram of a bistable electromagnetic relay with a control circuit.

A bistable relay with a control circuit contains a relay winding 1, a capacitor 2, a diode 3, the first - the third transistors 4.1-4.3, the first - the fifth resistors 5.1-5.5, the zener diode 6 with a stabilization voltage equal to the rated relay control voltage.

Bistable electromagnetic relay with a control circuit operates as follows.

The bistable electromagnetic relay is controlled by a voltage of one polarity: when turned on, it is activated at the corresponding position due to the charge current of the capacitor 2, and when the control voltage is removed, it is switched to another position by the reverse current due to the energy stored in the capacitor 2. When the control voltage is turned on when the voltage is exceeded stabilization of the Zener diode 6 appears current through the Zener diode 6 and, respectively, through the fourth and fifth resistors 5.4, 5.5 and the base of the third transistor 4.3. Transistor 4.3 jumps open and converts a slowly growing control voltage. Through the resistor 5.2, the surge jump unlocks the transistor 4.2 and through the resistor 5.1 it closes the transistor 4.1, which is already locked through the resistors 5.1 and 5.3 with a discharged capacitor 2. At the same time, a current surge appears through the diode 3, relay coil 1 and capacitor 3, which switches the relay to the position corresponding to the control voltage. Capacitor 2 begins to charge to a voltage equal to the sum of the voltage drop across resistor 5.3 and transistor 4.2. The current through winding 1 decreases and the relay remains in the set position.

The reverse switching of the relay due to the energy accumulated in the capacitor 2 occurs through a transistor 4.1, which in the presence of a control voltage is always locked through a resistor 5.2, a transistor 4.2 and a resistor 5.1. In addition, before and at the time of turning on, the transistor 4.1 is additionally locked by the fact that the capacitor 2 is discharged and there is no voltage removed from the capacitor 2 ,. unlocking this transistor. Such a double locking transistor

4.1 increases the reliability of the circuit.

When you turn off the control voltage at the time of its decrease below the stabilization voltage of the zener diode 6, the current through it and the base of the third transistor 4.3 is interrupted. Transistor 4.3 instantly closes and turns off the voltage to resistor 5.2. Since the diode is turned on opposite to the voltage on the capacitor 2, after the third transistor 4.3 is turned off, the current through the resistor 5.2 and the base of the transistor 4.2 is interrupted. The transistor instantly closes and the voltage from the charged capacitor 2 through the resistors 5.1 and 5.3 abruptly unlocks the transistor 4.1. A current pulse flows through it and the relay winding 1 from the charged capacitor 2 in the direction opposite to the current when charging the capacitor 2, which switches the relay 1 to the position corresponding to the switching off of the control voltage. When the capacitor 2 is discharged, the transistor 5.1 is locked and the relay remains in this position.

Subsequent switching of the relay when switching on and off the control voltage occurs in the order under consideration. In this case, the capacitance of the capacitor 2 and the resistance of the winding 1 determine the switching time and, therefore, the speed of the relay.

When controlling the switching on and off of the DC voltage, the fourth and fifth resistors 5.4 and 5.5, the third transistor 4.3 and the zener diode 6 are not needed.

In the proposed device, changes in the control voltage do not predominate, since they change in proportion to the charge current of the capacitor 2, from which the relay operates in one direction, and by the same amount of discharge current, switching the relay in the other direction.

When testing, four relays with parallel windings with a response current of 92 mA according to the passport consumed 1.56 mA instead of 5.5 mA, which are necessary for prototype control, i.e. the current is 5.5 / 1.56 = / 3.6 times less.

Claims (2)

Claim 1. A bistable electromagnetic relay with a control circuit containing leads for connecting a control voltage source, a diode, a relay coil, a capacitor and a first transistor, in which an emitter-collector junction is connected in parallel with the relay coil and a capacitor connected in series, and a first resistor, characterized in that, in order to increase reliability and reduce energy consumption, a second transistor, a second and a third resistor are introduced, the first resistor being connected to the base of the first transistor by the first output, and by the second the output is to the connection point of the collector of the second transistor and the first output of the third resistor, the second output of the third resistor is connected to the connection point of the relay winding and the capacitor, the first output of the second resistor is connected to the base of the second transistor, and the second output to one of the terminals for connecting the source control voltage, the emitter of the second transistor is connected to the emitter of the first transistor and to another terminal for connecting a source of control voltage. 2. Relay in π. 1, characterized in that, in order to increase reliability by providing control of the relay by a slowly varying control voltage, a third transistor, fourth and fifth resistors and a zener diode are introduced, and the emitter-collector junction of the third transistor is connected in series with the circuit formed by the diode, relay winding and capacitor, base the third transistor is connected to the first terminals of the fourth resistor ₅ , the second terminal of the fourth resistor is connected to the connection point of the first terminal of the fifth resistor and the zener diode, the second terminal of the fifth resistor is connected to the emitter of the third transistor and to one of the terminals for connecting the control voltage ¹⁰ , the other terminal of the zener diode is connected to the emitters of the first and second transistors and to another terminal for connecting the source of the control voltage.