SU703905A1 - Magnetic relay - Google Patents

Description

one

The invention relates to the field of electrical engineering and can be used, for example, for an intrinsically safe contact switch of electrical circuits.

A transistor relay is known, comprising two transistors, an electromagnetic relay coil, resistors, a control terminal and a diode 1.

The specified device is not economical and quite difficult.

The aim of the invention is to increase the economy and simplify the device.

To achieve this goal in a transistor relay containing two transistors, an electromagnetic relay coil in the collector circuit of the second transistor, a diode connected in parallel with the coil of the electromagnetic relay, control terminals, one of which is connected to the base of the second transistor through a resistor, the second resistor connected to the base of the second transistor, the ergitter of the first transistor is connected to the collector of the second transistor, the emitter of which is connected to the collector of the first transistor and the power supply bus; another pin the second resistor is connected to

The base of the first trans1 {stor, the base of the transistor is connected to the second control terminal.

The drawing shows a schematic diagram of the device.

Contact-controlled transistor relay contains electromagnetic relay I, transistor 2 of pn-type conduction, transistor 3 of pn-type of conductivity (transistors 2 and 3 - with additional

symmetry), resistor 4, resistor 5, diode 6, terminals 7 and 8 of the control of the transistor relay and the closing contact 9.

The device works as follows. Let contact 9 be open, but then the circuits are the positive output of the power supply -

emitter junction of transistor 3 - resistor 4 - emitter junction of transistor 2 - winding of electromagnetic relay 1 - minus terminal of the power source current flows. With a large resistance value of resistor 4, the base current is insufficient for opening transistors 2 and 3. The latter are closed, their collector points are very small. The current in the winding of the electromagnetic relay 1 is the total current of the transition of ORD emitter-collector of both closed: TfraiT3frctopoB is not enough to turn on the ST & Kf circuit.

Let pin 9 be closed, then resistor 5 is connected parallel to resistor 4.

The resistance of the resistor 5 is chosen to be small, so that the plus-pin of the power source — emitter junction of transistor 3 — is parallel to the connected resistor 4 to resistor 5 — electromagnetic transition of transistor 2 — winding of the relay 1 — minus output of the power source flows a current (base current), sufficient to open and translate the indicated transistors 2 and 3 into the saturation region.

Thus, when the transistor relay is closed (terminal 9), its transistors 2 and 3 are open, and the current in the winding

electromagnetic relay 1 is determined in

 BASIC, the resistance of the winding of the relay 1 (G TShrt and its ttara; t eel and but on VDH elsitterno-collector transitions of open transistors 2 and 3) and sufficient riOIff wk; bout Chen and el ohm and g and t here

The base current of low-power transistors is small. In the circuit under consideration, mamaloid transistors 2 and 3 are used, and the parameter - -rcHGG of the proposed transistor relay is chosen so that the current in the circuit of pin 9 - terminals 7 and 8 - resistor 5 - resistor 4 and the base current of transistor 2 (transistor 3) at closing contact 9

The base current of transistors 3 and 4 with uniform contact 10 is limited to a deliberately intrinsically safe value by resistor 5, which prevents the transistors from operating with the base turned off and the

e: This increases the reliability of the trance transistors in switch mode.

Resistor 6 limits the base current

open transistors 3 and 4 to the value

exclude thermal overheating base

transitions of transistors 3 and 4, which facilitates

the thermal mode of operation of transistors, after cttiHe chegoOs increases operation

 NZDEZhNbbtb- tr anzistornogo relay in general,

in addition, the resistor 6 provides the intrinsic safety of the input circuits under consideration

transistor relay

Diode 7 prevents the breakdown of the response of the OPOB when the electromagnetic relay is turned off due to the EMF of the sambiZHUKCIi that occurs at this moment in the winding of this relay.

Between the terminal 8 and the base of the transistor 4, a resistor may be connected that performs a function similar to the function of the resistor 6.; ; -, ;;

The proposed transistor relay is more / clocked, simpler, has a lower cost than the known one.

By reducing the number of elements in the circuit and by using low-power (and small-sized) elements, the overall dimensions and weight of the proposed transistor relay are significantly reduced.

The major advantage of the proposed transistor relay is that the control contact only switches the extremely small base current of the transistors, while the much larger value of the current through the coil of the electromagnetic relay is switched (without sparking) by the transistors. The value (due to the smallness of the base currents of low-power transistors) of the current is small, commuting-. our control contact causes low electrical erosion of the contact.

The proposed transistor relay can be controlled by micro-power microcontact contact sensors.

Due to the lower complexity of the proposed transistor relay, it has greater reliability. In the case of the electromagnetic relay relay coupled with integrated circuits (for example, from the RPG-2 series of intermediate miniature electromagnetic relays () with sealed contacts) in the circuit of the proposed transistor, the rest of the circuit of the proposed relay can have an integral design.

Claims (1)

Invention Formula A transistor relay containing two transistors, an electromagnetic relay coil in the collector circuit of the second transistor, a diode connected in parallel to the coil of the electromagnetic relay, control terminals, one of which is connected to the base of the first transistor through a resistor, the second resistor connected to the base of the second transistor, different the fact that, in order to increase ECONOMY and simplification, the emitter of the first transistor is connected to the collector of the second transistor, the emitter of which is connected to the collector of the first transistor and Another power source, another terminal of the second resistor is connected to the base of the first transistor, the base of the second transistor is connected to the second control terminal. Sources of information taken into account in the examination 1. B. V. Vermensky and others. Equipment and automation equipment for explosive atmospheres. M. “Energie, 1970, p. 26-27 (prototype). -. .