SU777749A1 - Switching-over device - Google Patents

Description

(54) SWITCHING DEVICE

The invention relates to the field of switching equipment. A switching device is known, which contains two transistors, in which the emitter circuit has a resistor connected, and a polarized relay 1. A disadvantage of the known device is low reliability, since the relay windings are switched through their own relay contacts. It is also known that a switching device containing two transistors connected in accordance with a trigger circuit with a common emitter resistor, a polarized relay with contacts, the terminals of the same name and the return winding of which are connected to the collectors of the transistors of the trigger, and the power supply 2. The disadvantage of this device the reliability is low due to the possible hanging of the moving relay contact. The aim of the invention is to increase reliability by eliminating the possibility of the movable contact of a polarized relay sticking under the action of shock loads. This goal is achieved in that the switching device is equipped with an electromagnetic relay, a resistor and a transistor, m, whose collector is connected to the emitter of the additional transistor through the resistor through the coil of the electromagnetic relay and through the resistor with opposite winding leads of a polarized relay, and the base of the additional transistor is connected to the moving contact of a polarized relay, not odvizhnye contacts which are connected to the collectors tranzistorrv trigger. The drawing shows a switching device ..,, .. The switching device contains transistors / -3, a power supply 4, a polarized relay 5 with a direct winding 6 and a return winding 7, a moving contact 8 n fixed 9-10, an electromagnetic relay // with normally closing open contact 12, resistors 13-18, diodes 19-20. The device works as follows. In the absence of an input signal U in transistor / closed, transistor 2 is open, transistor 3 is closed, as the "+ power supply through the resistor 13 and closed contacts 9-5 of the polarized relay 5 is attached to its base. At the same time, the relay //

de-energized, its contact 12 is open and the windings 6 II 7 relays 5 are also de-energized. When the input signal / "reaches a value equal to the voltage across the resistor 16, the transistor / opens, the transistor 2 closes, and the transistor 3 opens at a value:" - power supply 4, resistor 16, open E | Mitter - colo-vector junction of the transistor /, contacts | 9-8 relays 5. This triggers the relay // and, with its closing contact 12, supplies power to the winding 6 of relay 5, the iKOTOpoe triggers and relocates the moving contact 8 to the stationary 10. When the contact 8 is closed with contact 10 « + power supply 4 via resistor 14 and closed contacts Kty 10-8 is applied to the base of the transistor 8, which closes and de-energizes the winding of the relay. The contact 12 opens and the winding 6 de-energizes.

When the input voltage ... becomes less than the voltage across the resistor 16, the transistor / closes, transistor 5 opens, transistor 3 also opens along the circuit; "- power supply 4, resistor 16, open emitter-collector junction of transistor 2, closed contacts 10- 8 relay 5, the base of the transistor 3. This triggers the relay 11 and sends its contact 12 to the winding 7 of the relay 5, which is triggered by transferring the moving contact 8 to the non-iodine 10. As soon as the contacts 5 and 9 are closed, the base of the transistor 5 through the contacts 8 -9 and resistor 13 connect with a positive power supply 4 iolyusu. The transistor 3 is closed, the relay // is de-energized, the contact 12 times is closed, the winding 7 of the relay 5 loses power. If for any reason contact 8 of relay 5 hangs in the mediumSM-position, then transistor 3 will open in the following circuit: "- power supply 4, resistor 17, base of transistor 3. This will trigger the relay //, contact 12 of this relay will close and the winding 7 of the relay 5 through the open transistor 2 and the resistor 16 is connected to the source 4, the relay 5 is activated, returning its moving contact 8

the immobile contact 9 to the initial state.

Similarly, in the case of the presence of an input signal B and a freezing of the movable contact 8, the sequence will return to its original state at the fixed contact 10.

Diodes 19 and 20 protect the collector - the emitter junction of the transistors / -3 from overvoltages, as well as eliminating the bounce | K; Onktotov relays.

Claims (2)

1. Authors certificate USSR Lz 365837, cl. H 03 K 17/56, 1968. 2. Authors certificate of the USSR 447775. cl. H 01 H 47/32, 1974 (prototype).  n IS A y / x m