SU754509A1 - Timer - Google Patents

Description

The invention relates to automation, namely, devices time delay.

A time relay is known, which contains a timed KS circuit, an input 5 amplifier at a transistor connected in a common emitter circuit, and an output amplifier with an electromagnetic relay [Ί].

The disadvantage of this time relay is the absence of a circuit element, which includes the capacitor of the timing circuit for discharge and the preparation of the circuit for a new time reference, as well as a long recovery time. 15

It is also known a time relay containing an amplifier on two transistors with a KS circuit connected to the base of one of them, and a winding of an electromagnetic relay connected to the collector 20 circuit of the other, and a start switch connected to the negative pole of the power supply, the additional winding of the relay performed by a two-position with self-holding, and a capacitor are connected between the starting key and the positive pole of the power source [2].

The disadvantage of this time relay is a long recovery time2

of a capacitor connected sequentially with an additional relay winding, which degrades the speed of the circuit. The discharge of the capacitor occurs through the timing resistor.

Re-enabling the control key earlier than this time may cause a relay to trip. "

The aim of the invention is to increase the speed and reliability by reducing the recovery time of the circuit from the end of the time delay to the beginning of a new reference.

This is achieved by the fact that in a time relay containing an amplifier on two transistors with a KS circuit connected to the base of one of them, a winding of an electromagnetic relay connected to the collector circuit of the other, a start switch connected to the negative pole of the power supply and an additional winding of a two-posed self-holding relay and a switching capacitor, additionally introduced are resistors of a voltage divider, a switching transistor, the collector of which is connected to one of the additional volt output t ki and via COP-chain - with the amplifier input and the common point of the two divider

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754509

resistors are connected to the base of the switching transistor, one of the divider resistors and the emitter of the switching transistor are connected to the positive pole of the power supply, and a switching capacitor is connected between the connection point of the second output of the auxiliary winding and the starting switch and the second resistor of the divider

The drawing presents a circuit diagram of a time relay.

At the input of the relay amplifier on two transistors 1 and 2 of different types of conductivity included timing circuit consisting of resistors 3,

4 and the capacitor 5. To compensate for the temperature coefficient of the capacitance of the capacitor 5 in the emitter of the transistor 1 is a switching diode 6.

In the initial state, the capacitor 5 is discharged through the resistor 4 and the contact 7 of the relay. The divider, consisting of resistors 8 and 9, determines the operating point of the transistor 2, the load of which is the tripping winding 10 of the two-position relay with a hold. The turn-on winding 11 of the mentioned relay is connected with one output to the control contact of the switch 12, the other output to the collector of the switching transistor 13 and to the resistor 3 of the time reference circuit. The control contact of the key 1.2 is also connected via a switching capacitor 14 and a divider consisting of resistors 15 and 16 to the common point of the amplifier and the positive pole of the power source 17. The divider from resistors 15 and 16. determines the operating mode of the transistor 13, to the base of which is connected a common point divider.

The contact 18 of the relay supplies voltage to the load, 19 During the time determined by the time delay of the relay.

In the initial state, the key 12 is open, the timing capacitor 5 is closed by pin 7 through a low-resistance resistor 4 and is completely discharged. When the switch key 12 closes, the charge current of the capacitor 14, passing through the divider of resistors 15 and 16, creates a voltage drop across the resistor 16, opening the transistor 13 for the duration of the charge of the capacitor 14 through the resistor 15. Through the winding of the relay 11 and the open transistor 13. relay operation. The capacitor 14 may have a relatively small amount of capacitance, as it is included in the base circuit of the transistor! 3, which is an amplifier.

After the relay trips, its contact 7 opens and stops capacitor 5 bypassing, and contact 18, closing, applies voltage to load 19. After charging capacitor 14, transistor 13 closes and capacitor 5 starts charging through resistor 3. When the voltage on the capacitor increases · 5 to the turn-on voltage of diode 6 opens the transistors 1 and 2 of the amplifier, the current flows through the disconnecting winding 10 of the relay and pin 18 opens, removes the voltage from the load 19. Contact 7 of the relay closes the capacitor 5 through resis torus 4. Transistors 1 and 2 are closed, and the winding 10 of the relay is de-energized.

When opening the control contact of the key 12, the capacitor 14 is discharged through a divider of resistors 15, 16, pin 7, resistors 3, 4 and the winding 11 of the relay, while the discharge time is less due to the smaller value of the switching capacitor 14.

Thus, the restoration of the circuit in the time relay is much faster compared with the prototype circuit, as a result of which the speed and reliability of operation increases.

Claims (1)

Claim A time relay containing an amplifier on two transistors with a KS circuit connected to the base of one of them, and a winding of an electromagnetic relay connected to the collector circuit of the other, a starting switch connected to the negative pole of the power source and an additional winding of the mentioned relay, made two-position with self-holding , and a switching capacitor, characterized in that, in order to increase speed and reliability by reducing the duration of the restoration of the circuit from the moment of the end of the time delay to the new eta, resistors of a voltage divider and a switching transistor whose collector is connected to one of the additional winding pins and through a COP circuit to the input of the amplifier, the common point of the divider of two resistors is connected to the base of the switching transistor, one of the resistor of the divider and the switching emitter the transistor is connected to the positive pole of the power source, and a switching capacitor is connected between the point of connection of the second output of the auxiliary winding with the start key and the second resistor ohm divider.