SU809426A1 - Device for switching-on actuating relay - Google Patents

Description

(54) DEVICE TO ENABLE EXECUTIVE RELAY

one

The invention relates to automation and can be used to turn on actuating relays of railway automation devices, for example, to control railroad switches.

A device for switching on actuators is known, comprising a power supply unit, a relay activation inhibitor unit connected to it, storage cells and an amplifier, the output of which is connected to the relay coil 1.

The disadvantage of the device is the low reliability of the device.

Of the known devices for switching on the executive relay, the device for switching on the executive relay containing the relay inhibiting block, the first and second inputs of which are connected respectively to the first and second inputs of the device, the third input to the perist output of the power supply and the first input of the pulse shaping unit, and the output — from Ztora and the input of the forashiruing unit: pulses, the third input of which is connected to the third input of the device, and the output through

the primary winding of the transformer to the second output of the power supply unit, the first output of the secondary winding of the transformer is connected to the first output winding of the executive relay, in parallel with which accumulating element 2 is connected,

When the power supply unit and the remaining units of the device are in good condition, the actuating relay switches on after multiple pulses of energization, in the absence of a ban on switching on the relay - when energy is accumulated

5 on the bypass winding of the relay capacitor to the relay trigger voltage. However, when voltage pulsations occur, a false activation of the executive rail occurs, since the variable component of the supply voltage is transmitted through a transformer, converted by the rectifier into DC pulses, causing energy accumulation

5 capacitor, to the value of the relay trigger voltage.

The purpose of the invention is to improve the reliability of the device,

This goal is achieved by the fact that

In the known device, an opically coupled photodetector and a light source connected to the network output of the power source are inserted, the second side of the transformer’s secondary winding is connected via a photoreceiver to the second output side of the executive relay.

The drawing shows the functional diagram of the device for switching on the secondary relay.

The device comprises: block 2 of the prohibition of switching on the relay, block 3 of generation of pulses, transformer 4 with primary winding 4 and secondary 4 windings, (photo thyristor) photodetector 5, executive relay 6; accumulating element (capacitor) 7, light source 8 (LED), the first (signal) input 9 of the device, the second (prohibiting) input 10 of the device, the third (clock) input 11 of the device.

The device for turning on the executive relay operates as follows.

When the power supply unit 1 is in good condition, when the voltage ripples at its outputs are absent, the LED 8 produces a constant light intensity. Under the action of this luminous flux, the resistance of the photothyristor 5 in the conducting direction decreases to a value sufficient to pass the charging current of the capacitor 7. If there is a signal to prohibit the switching on of the relay, which is fed to the second input 10 of the device, the voltage on the capacitor 7 is absent and the executive relay 6 will be turned off regardless of whether the turn-on signals are received at the first input of the device 9 or not. After removing the prohibition on switching on the actuating relay b from the second input 10 of the device and in the presence of -signals turning on at its first input 9, the block preventing the switching on of relay 2 at its output generates DC pulses. The pulse shaping unit 3 generates the switching pulses of the executive mode 6 to the duration and power required for switching on the exhaust relay 6. The pulse duration is determined by the time interval between the signals on the first and third inputs of the device. From the output of the unit 3, the pulses are poked into the primary winding 4 of the transformer 4, while in the secondary winding 4 of the transformer 4 there is an emf. The photo thyristor 5 converts it into DC pulses that recharge the capacitor 7. When pulsed signals are repeatedly applied to turn on the actuating relay b, the energy on the capacitor 7 is accumulated to the magnitude of the operation of the voltage and the executive relay b is turned on. When a ban is applied to turn on the generation of pulse signals at the output of the unit, the turn on relay 2 stops and after the discharge of the capacitor 7, the executive switch 6 is turned off.

When a pulsating power supply arises when a power supply unit 1 fails, the luminous flux produced by the LED 8 will change its intensity. The variable voltage component in this case will induce in the secondary winding 4 of the transformer 4 EMF. However, this phase of the EMF will be opposite to the phase of the alternating component of the supply voltage. At the time of the positive half-wave of the pulsating supply voltage, the luminous flux produced by the LED 8 will be maximum, which means that the resistance in the conductive direction of the photo thyristor 5 will be minimal, while the secondary voltage of the transformer 4 will act on the secondary winding 4, the photo-thyristor 5 will be for it connected in a non-conductive direction and no charge of capacitor 7 occurs. Conversely, the positive half-wave of the EMF acting on the secondary winding 4 corresponds to the negative half-wave of the pulsating supply voltage, at which the light flux of the LED 8 will be minimal, and the resistance of the photo thyristor 5 in the conducting direction will be maximal. The current flowing through the photothyristo in this case

5 will be insufficient to charge the capacitor 7 to the magnitude of the actuating voltage of the actuating relay.

6. Therefore it is not included. Malfunction of any item

This device, including the light source 8 and the photodetector 5, does not lead to the false activation of the executive relay b.

The use of new elements of the light source 8, connected to power supply 1, the connection of the executive relay b to the secondary winding 4 of the transformer 4 via a photodetector 5 connected to the light source 8 by optical communication, distinguishes the invention from the prototype. It has protection against false activation of the executive relay b in case of malfunction of power supply unit 1, which ensures higher reliability of the device, and, consequently, railway automation devices.

Claims (2)

1. USSR author's certificate No. 542258, cl. H 01 H 47 / 00.22.08.74. 2.Automation, Remote Control and Communication, 1979, No. 1, p. 6-9.