SU757984A1 - Device for measuring motion velocity of railway vehicle - Google Patents

Description

The invention relates to measuring equipment and can be used in railway transport and in the coal industry.

A device for measuring the speed of the correlation method £ ΐ3

However, such a device cannot be used to measure the speed of a rail vehicle.

It is also known a device for measuring speed, containing two successively installed along the direction of movement of the sensor, a generator of the reference frequency, detectors of the output 1 sensor signals, a comparator, an adjustable delay unit and an indicator of the delay value [2].

The disadvantage of this device is low accuracy when using it2 to measure the speed of movement of rail vehicles.

The purpose of the invention is to improve the accuracy of measuring speed.

This goal is achieved by the fact that 2 the proposed device is equipped with two additional series-installed sensors with detectors connected to their outputs, two generators of controlled frequency

2

You, the outputs of which are connected to additional sensors and to additional input null organs, second comparators connected in series by the multiplication unit and the integrator, while the comparators are connected between the outputs of the detectors of the respective main and additional sensors and the control inputs of the controlled frequency generators, the output of the first of which is connected to the first input of the multiplication unit, the output of the second - to the input of the adjustable delay unit, the output of which is connected to the second input of the multiplication unit, and control input-governing adjustable delay block connected to the output of the integrator.

FIG. 1 shows a block diagram of the proposed device; 2 shows the location of the sensors relative to the rails.

The device includes sensors of the main channel, additional sensors 3 and 4, a reference frequency generator 5, current comparators 6 and 7, amplitude detectors 8-11, controlled frequency generators 12 and 13, zero-bodies 14 and 15, an unregulated delay block 16, multiplication unit 17, in757984

Tegtor 18 and indicator device 19 ".

The reference frequency generator is sucking! The formation of a sinusoidal signal of a constant frequency, which comes in the main channel encoder sensors. Sensors 1-4, located on the lo- ³ komotnve in close proximity to the rails {see fig. 2), are parametric, and as the information parameter is used the change in capacitance between the surfaces of the sensor and the rail when the locomotive moves. ' Through amplitude detectors, the sensor outputs are connected to current comparators, at the outputs of which mismatch signals are generated that control the frequency of the generators 12 and 13. The outputs of these generators are connected to additional sensors 3,4 and to zero-parts transition of alternating voltage through zeros. The output of the first zero-body is connected to one of the inputs of the multiplication unit, and the output of the second through the adjustable delay unit is connected to the second output. The integrator 25, the output of which is connected to the adjustable delay unit, and the input to the multiplication unit, computes with the latter the computation of the cross-correlation function.

The indicator connected to the block ^of adjustable delay counts the speed of the locomotive.

The device works as follows. ,

When the locomotive moves (in the direction of the arrow indicated in figure 2), the mutual capacitances between the surfaces of the sensors 1-4 and the rails of the railway track change, which leads to a change in the currents in the measuring circuits.

Amplitude detectors carry out the selection of low-frequency components of the signals that are fed to the input of the current comparators. In the comparator 7, the low-frequency components of the first (in the direction of travel) pair of sensors are compared>, and in the comparator 6, the second. Comparator mismatch signals determine the frequency of the generator ,. Rose 12 and 13, The currents of the sensors of the additional channel, in turn, are determined by the frequency of the generators 12 and 13, which, through feedback, maintain the error signals from the comparators · minimal. Further, 55 generator output signals modulated by surface inhomogeneities.

rails arrive at the zero-bodies 14 and 15, which carry out the formation of pulses during the transition of sinusoids through zeros. The multiplication unit multiplies the signal from the second pair of sensors with the time-delayed signal from the first pair of sensors. The integrator's output signal, by changing the delay time of the adjustable delay block, ensures the device is tuned to the maximum of the cross-correlation function. The magnitude of the delay using the indicator device 19 is determined by the speed of movement of the locomotive,

Claims (1)

Claim Device for measuring the speed of movement of a rail vehicle, containing two successively installed along the direction of movement of the sensor connected to the output of the reference frequency generator, detectors of the output signals of the sensors, a comparator, a delay unit and an indicator of the amount of delay, characterized in that accuracy, it is equipped with two additional series-mounted sensors with detectors connected to their outputs, two controlled frequency generators, the outputs of which are Linked to additional sensors and to additionally introduced null organs, a second "comparator, sequentially switched on by the multiplication unit and an integrator, while the comparators are connected between the outputs of the detectors of the respective main and additional sensors and control inputs of the controlled frequency generators, the output of the first of which is connected to the first input multiplication unit, the output of the second - to the input of the adjustable delay unit, the output of which is connected to the second input of the multiplication unit, and the control input of the control unit iruemoy delay connected to the output of the integrator.