RU2001801C1 - Point resonant path-control transducer - Google Patents

Description

The invention relates to track automation devices and can be used as sensors in self-locking systems, in automatic slide centralization stations, in electrical centralization stations, in overheating axlebox control devices, etc.

Point track sensors are known, for example, a Siemens magnetic contact sensor. Its magnetocontact system (permanent magnets and a polarized contact insert), mounted on shock absorbers in a sealed housing made of diamagnetic material, has a plug connection with a two-wire cable,

The sensor with a gas-tight contact insert (reed switch) consists of a compensating magnetic circuit with permanent magnets, which are placed in an aluminum case and filled with epoxy resin.

Integra's electromagnetic inductive track sensor (Switzerland) consists of two halves that are attached to a steel base located on a rail and connected to rails. When the wheelset moves over the sensor, the magnetic lines of force of the alternating fields of both halves of the sensor are folded and closed through their magnetic cores, the steel base and the wheelset. Therefore, the inductive reactance of the sensor increases and the current in the actuators decreases, which is detected by the sensor circuit.

The magnetic induction sensor of Servo and General Electric (USA) is a horseshoe-shaped permanent magnet with windings at the poles located in a diamagnetic case. As the wheel enters the sensor range, the magnetic flux changes and is induced in both coils with an EMF with an amplitude proportional to the speed of the wheel.

One of the Siemens sensor modifications consists of two parts. On the outside of the track, one part with two radiating ones is fixed on the rail, and the other part with two receiving windings is fastened on the rail. The converters, generator, stabilizer, electronic protection and output transformer are mounted on printed circuit boards, which are located in the trip box on the side of the path.

The sensor detects the passage of wheels at a speed of its movement from 0 to 250 km / h and an ambient temperature from -40 ° C to + 80 ° C, the power consumption is BW. sensor weight 20 kg.

The Siemens eddy current capsule sensor consists of a steel box with a copper capsule which is pressed into the hole drilled in the rail head and a cable sleeve that is attached to the rail neck. In the capsule is an epoxy resin-filled transformer with an open magnetic circuit, and in the sleeve into which the cable is inserted. - auto generator. The rolling stock is secured at a speed of 0 to 50 km / h.

Piezoelectric travel sensors using quartz crystals were developed by Sumimoto Electric Industry Ltd., a Japanese company. The sensor consists of two identical parts attached to

5 rail neck on both sides. The vertical deflections of the rail under the action of the load are converted by piezoelectric elements into electrical signals, which are transmitted via a shielded cable to the track box, where

0 are amplified and transformed again. The range of the sensor is about 400 mm. The sensor detects wheels moving at a speed of at least 1 km / 1h.

Similar developments are known in

5 USSR. The proximity switch contains a magnetic circuit with a winding of a series resonant LC circuit, a differential transformer, through one compensating winding

0 of which the serial LC circuit is connected to the power source, and an adjustable resistor is included in the circuit of the second compensating winding of the transformer, in series with which is connected

5 parallel resonant LC circuit. The signal winding of the differential transformer through the amplifier is connected to the actuator. Directional switch operates to stall 0

in serial and parallel

LC circuits when a controlled mechanism appears in the magnetoprop zone.

All of the above sensors have significant drawbacks.

5 Thus, a magneto-induction sensor does not detect a fixed pair of wheels located in the range of a sensitive element (there is no induced emf). The eddy current sensor operates at a rolling stock speed of only 50 km / h. Piezoelectric sensors respond to the amount of rail deflection, and in cold weather the rails become less flexible and failures occur.

5Contact sensors have insufficient reliability, since it is almost impossible to fine-tune them due to varying degrees of wear on wheelsets and rails. The most advanced of them have a finite number of responses and their service life is many times less than the life of non-contact sensors. The Siemens sensor, consisting of two parts with radiating and receiving windings, has rather high technical characteristics (it captures rolling stock at speeds from 0 to 250 km / h, low energy consumption of 5 W, sufficient temperature range from -40 to + 80 ° C), but the location of all the blocks in the tracker near the track dramatically complicates and increases the cost of the structure, increases the mass (20

kg).

The design of the proximity switch also has drawbacks. These include, first of all, the complexity of the circuit and the need to maintain resonance modes at the same frequency in two circuits, which is difficult to achieve with changes in the circuit parameters caused by fluctuations in the ambient temperature. This affects the performance of the switch (conversion coefficient) and reduces its reliability,

The purpose of the invention is to increase the reliability of the sensor.

The goal is achieved in that in a point resonant track sensor containing a magnetic circuit, on which a signal winding is located, connected to a generator and through an amplifier with an indicator, a parallel LC circuit having an inductive winding, characterized in that, in order to increase reliability, the magnetic circuit is made U-shaped, made of ferrite, the inductive winding of the LC circuit is made of two parts that are installed on one and the other branches of the magnetic circuit, and the signal winding is placed on the jumper.

In FIG. 1 shows a sensor circuit; in FIG. 2 is a circuit diagram for replacing a sensor element; FIG. 3 is a circuit diagram of one of the sensor options.

A point resonant track sensor contains a U-shaped ferrite magnetic core 1, a coil of parallel resonant circuit 2, divided into two identical parts 3 and 4, as a sensitive reindeer, and a capacitor 5 enters the resonant circuit. A wire is made of a U-shaped ferrite magnet 2, its horizontal part is also wound around an excitation winding 6, powered by an alternating voltage generator 7 connected to a power unit 9, an amplifier 8 connected to an actuator or output m relay. Last three elements 7,0,9

constitute signal processing unit 10.

The sensor operates as follows. Field winding G wound on a 5 U-shaped ferrite core 2 from the sensor 1 is powered by an alternating voltage generator 7. The magnitude of the current h is controlled by an amplifier 8. The frequency of the voltage can

0 change when adjusting the resonance mode of the parallel LC circuit (inductance 3.4 and capacitor 5),

When a sensing element 1 is monitored in the operating zone

5 of the mechanism, the operating mode of the LC circuit changes due to the violation of the resonance mode, which leads to a change in the magnitude of currents 2 and It. A signal proportional to the magnitude of the current And is fed to amplifier 8 and

0 after processing - to the output terminals, to which the actuator, or other automation devices can be connected. Generator 7 and amplifier 8 are powered by power supply 9.

5 For a more detailed description of the principle of operation of the sensor, we consider the electrical equivalent circuit of the sensing element 1 (Fig. 2). New notation has been introduced in this diagram. Inductance Inductors

0, current 3 and 4, due to their identity, are indicated by L2, the active resistances of these windings are indicated by R2. The inductance of the field winding 6 is denoted by Li, its active resistance is denoted by RI

5 Capacitor 5 is denoted by C.

In mm inductance between windings 3 and b, 4 and 6, due to the symmetry of the magnetic system, is denoted by M, through the insertion resistance, by

0 loolem occurrence in a magnetic field of a sensitive element of a controlled mechanism. The value of 2Bn is determined by the value of the losses arising in the conductive roof of the mechanism when it is consumed

5 alternating electromagnetic field, with the created magnetic system of a w / real element.

It should be noted that the value 0 of the introduced resistance is not constant, but depends on the distance of the conductive surface of the controlled mechanism from the ends of the magnetic circuit 2 In experimental studies,

but it is established that the ratio

by my

muzzle varies from 8-12 at rfc-tchti 6-8 mm. up to 1.3 at a distance of MIs from the conducting surface to the center of the MAG

kigoprovoda. In the theoretical determination of the value of ZBH, the recommendations in the book by V.A. Govorkov, Electric and magnetic fields, were used.

In FIG. 3 is a circuit diagram of one embodiment of a sensor. The master oscillator is assembled on a chip DL of resistances Ri, R2, capacitance Ci and inductance C}, power is supplied to the midpoint.

The oscillator frequency of the generator can be controlled by moving the ferrite core of the induction coupling coil TP1. The L5C2 oscillation circuit is designed to stabilize the frequency of the generator.

The oscillations induced in the winding through the series inductance Le of the coil with a ferrite (unregulated) core are fed to the excitation winding Li of the sensing element.

The oscillator frequency is selected such. so that resonance occurs in the parallel LC circuit of the sensing element.

The magnitude of the voltage is proportional to the magnitude of the current I. is removed from the winding

Claims (1)

The claims POINT RESONANCE WAY YOUR SENSOR containing a magnetic circuit mounted on a rail on which a signal winding is placed, connected to a generator and through an amplifier - with a signaling device, parallel LC circuit 5 0 5 0 5 I coil TP2 and goes to the base of transistor VT1 (amplifier input). Resistances R3, R4 are selected so that when the resonant sensor is tuned to resonance, the LED VD1 is lit. On the transistor VT4 assembled output stage. The connection of transistors VT2 and VT3 (Fig.Z) provides a clear operation of the circuit when the mode changes, i.e. when a controlled mechanism appears in the zone of action of the sensitive element. In this case, the signal disappears at the output terminals (VT4 closes). When a controlled mechanism appears, the current AND decreases significantly in value, the LED VD1 goes out, which allows you to visually monitor the correct operation of the sensor. The threshold device on the transistors VT2, VT3 is reset, the transistor VT4 is closed. The VD2 diode eliminates contact bounce of an electromechanical or reed switch connected to the output echoes of the amplifier. (56) Copyright certificate of the USSR No. 481482.cl. In 61 L1 / 08, 1973. having an inductive winding, characterized in that the magnetic circuit is made U-shaped from ferrite, the inductive coil of the LC circuit is made of two parts that are mounted on one and the other branches of the magnetic circuit, and the signal coil is placed on the jumper. Editor T. Pavlovsk Compiled by V. Zaitsev Tehred M. Morgenthal Proofreader M. Kul