SU131838A1 - Contactless Electromechanical Resonance Relay - Google Patents

Description

The commonly used electromechanical resonance contactless relays containing a magnetic core provided with input windings and a steel vibrator in the air gap of one of the cores of the magnetic circuit do not have the sensitivity necessary, in particular, to use them in laboratory conditions.

In the described relay, the increase in sensitivity is achieved by applying an additional magnetic bias winding of the magnetic conductor, which is coupled through the bridge rectifier by the current of the imbalance of the bridge circuit from the input windings of the magnetic conductor, which flows through the load.

The drawing shows a diagram of the described relay.

The three-core core of the magnetic circuit has an air gap in one of the extreme rods, in which a steel plate-vibrator is placed. The inductances of the windings Wi and Wz and the voltage across them are selected so that the current in the load R, with a stationary vibrator, is zero. A bridge rectifier 2 on semiconductor diodes is sequentially connected, the voltage from which through a choke 3 is applied to the positive feedback winding W located on the middle rod.

When the frequency of the input signal Ug., Approaches the resonant frequency of the vibrator, the gap decreases due to its oscillations, which leads to an increase in the inductance of the winding W.2, and the circuit becomes unbalanced. The imbalance current flows through the load resistance n of the rectifier circuit 2, which has a positive feedback W. W. The winding current, biasing reduces the inductance of the winding Wl, but does not affect practically the inductance of the winding Ws due to significant air clearance. Therefore, the imbalance of the circuit increases. The throttle 3 increases the resistance of the control circuit, because

alternating voltage arises on the winding Ws. The rectifier loaded with the winding Wz is connected in series with the load K „; therefore, a certain decrease in voltage due to a voltage drop across the rectifier circuit is unavoidable. However, the feedback does not only compass this reduction of the voltage Uw. but ultimately it increases the sensitivity of the relay by several times in comparison with the variant without feedback.

Prevention and Conspiracy

A contactless electromechanical resonance relay, containing, a magnetic core with input windings and a steel vibrator in the air gap of this magnetic circuit, characterized in that, in order to increase the sensitivity of the relay, these windings are included in a bridge circuit and a load and bridge rectifier are connected in series to which the magnetic winding of the magnetic circuit is connected, fed by the current of the unbalance of the bridge circuit.

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