SU742225A1 - Decoder for pulsed track circuit - Google Patents

Description

The invention relates to railway automatics and telemechanics devices and can be used in track circuits as a decoder for the impulse operation of a track relay, as well as in automatic locomotive signaling systems for high-speed traffic. A known decoder for a pulsed rail circuit containing contacts of a pulsed traveling relay, a neutral relay, in parallel with which a capacitor is connected, a power source 1. However, during operation of a known device, uncontrolled failures are possible. Thus, for example, when a normally closed and normally open contacts of a pulsed traveling relay are closed (welded), the neutral relay remains under current while the rolling stock of the rail tracker is effectively reduced, which reduces the reliability of the well-known decoder The purpose of the invention is to increase reliability. The goal has been achieved by the fact that the decoder is equipped with a multivibrator made on transistors, with the base of one transistor connected and to the positive pole of the power source through one normally open contact of a pulsed traveling relay, and the base of the other transistor is connected to the negative pole of the power source through series-connected another normal open-ended contact of a pulsed traveling relay and a storage capacitor, while the collector of one transistor is connected through a series-connected amplifier, transformer, filter and rectifier with a neutral relay. The drawing shows a schematic diagram of the decoder. The decoder contains a neutral turnip 1, a power source with a positive 2 and a negative 3 poles, a storage capacitor 4, a multivibrator 5, made on transistors 6 and 7 pp-p type, the base of transistor 6 being connected to the positive pole 2 of the power source through a normally open contact 8 of the pulse traveling relay (not shown in the drawing). Base trans

Eistor 7 is connected to the negative pole 3 of the power supply through a normally open contact 9 of a pulsed traveling relay and storage capacitor 4 connected in series. Parallel to the storage capacitor -4 is connected an amplifier 10 made on an r-11 type transistor emitter. The base of the transistor of the amplifier 10 is connected via a resistor 11 to the collector of the transistor b of the multivibrator 5. The collector of the transistor 10 is connected via a transformer 12, the filter 13 and the rectifier 14 to a neutral relay 1, while in parallel the relay 1 is connected a capacitor 15.

The decoder also contains resistors 16, 17, 18, 19, 20, 21 and capacitors 22, 23, 24, 25.

The decoder works as follows.

The impulse track relay periodically pulls and releases the measles under the action of signals from the track circuit. When the impulse track relay is triggered, the base of transistor 6 of the multivibrator 5 is connected to pole 2 of the power supply due to contact closure 8, and the transistor b closes and remains in as long as the impulse track relay does not release its measles. At the same time, due to the closure of the contact 9, the storage capacitor 4 is charged along the circuit of the pole 2 of the power supply through the emitter-base junction of transistor 7, and the pin 9 to the pole 3 of the power supply. The transistor 7 is in the open state at the time of the closed state of the transistor 6. The transistor of the amplifier 10 at the specified state of the transistor b is closed.

After the cortex of the impulse traveling relay decelerates the wound, the multivibrator 5 begins to work, and a high-frequency alternating voltage is applied from the collector of transistor 6 to the base of the transistor of amplifier 10, which is amplified by it. The power supply of the transistor amplifier 10 carries out an accumulative capacitor 4. Amplified alternating voltage through a transformer 12, filter 13, which can be made on the basis of inductively coupled circuits, and a discharge lv1 14 feeds the neutral relay 1. Relay 1 attracts its measles and continues hold it due to deceleration due to capacitor 15 during normal impulse operation of the impulse track relay. In case of violation of the normal pulse operation of the pulse track relay, as well as

when various faults occur in the scheme of the proposed device, relay 1 releases its measles. So, for example, in the case of sticking of contact 9 of a pulse glue relay, due to

With a large capacitance of the storage capacitor 4, the base potential of the transistor 7 of the multivibrator 5 after the charge of the capacitor 4 is approximately constant and the transistor 7 is kept open. This inhibits multivibrator 5, and relay 1 releases its measles. Protection against parasitic generation of the amplifier 10 on the transistor at its break

0 base provides a filter 13. With a simultaneous break of the capacitor 4 and sticking of the pin 9, the frequency of the multivibrator 5 changes, since parallel to the base resistor 18

5, the transistor 7 connects the resistance of the primary winding of the transformer 12.

Claims (1)

1. Stepanov N.M. Increase reliability and coding circuits of track circuits. - Automation, Remote Control and Communication, 1974, No. 1, p. 3-6.