SU1355526A1 - Device for measuring and checking wear of friction linings - Google Patents

Abstract

FIELD OF THE INVENTION The invention relates to a transnormal and agricultural machinery industry, namely to devices for measuring and controlling the wear of friction brake linings. The purpose of the invention is to enhance the functionality by measuring the wear in the metallized linings. To achieve the goal, the sensor 1 is made of optical fibers mounted on the base 2 and installed in the cover plate 3. The control device is made in the form of a multivibrator 7 with LEDs 5 and 6, which are connected to the photodiode 8 by means of the optical fibers of the sensor 1 and the calibration light 4. 10, the automatic gain control maintains a constant amplitude of the pulse from the amplifier 9, while the pulse depth is determined by the number of optical fibers of the sensor, i.e. the amount of wear of the friction lining. After inversion in block II, indicator 12 measures a constant component of the signal proportional to the amount of wear. 2 Il. SB (L Cpuej 00 ate sd ate 05

Description

The invention relates to a transport and agricultural machinery industry, namely to devices for measuring and monitoring the wear of friction linings of brake devices.

The purpose of the invention is to enhance the functionality by measuring and controlling metallized linings.

FIG. 1 shows a device for measuring and monitoring the wear of friction linings; in fig. 2 - time-pulse diagram.

Sensor 1 is made in the form of light guides arranged in the slots of plate 2 fixed in the thickness of friction lining 3. In addition, the device contains a calibration light guide 4, LEDs 5 and 6, a multivibrator 7, a photodiode 8, a photocurrent amplifier 9, unit 10 automatic gain control, inverter II and indicator 12. The light guides prevent the effect of the electrically conductive layer from the wear particles on the operation of the device. The ends of all the optical fibers of sensor 1 are connected together. The input ends of the optical fibers of the sensor 1 and the calibration light guide 4 are installed opposite the LEDs 5 and 6 connected to the square pulse generator — the multivibrator 7. The output ends of the optical fibers 1 and 4 are installed opposite the photodiode 8, which changes its light flux into a change in electric current. Photodiode 8 is connected to the power source through the resistance Rn. The power source is an auto-adjustment unit 10, which, by changing the supply voltage of the photodiode 8, maintains the amplitude of the pulse at the output of the photocurrent amplifier 9 connected to the photodiode 8 constant. The amplifier 9 is connected to the input of the inverter 11, which is an amplifier with a gain of 1, the output of which is in the opposite phase of the input. To the output of the inverter 1I connected indicator 12, recording the amount of wear.

The device works as follows. During operation, the brake devices of the brake lining surface 3 and the plate 2 wear out and fray the sensor elements I, which leads to a decrease in the cross section of the light guide and, consequently, the luminous flux from the LED 6 to the photodiode 8. Calibration is performed as follows. LEDs 5 and 6 are connected to both outputs of the multivibrator 7. The voltage on one of them is shown in FIG. 2a Voltage

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the other is out of phase with the first. The cross section of the light guide 4 is selected so that the luminous flux passing through this light guide will always be greater than the luminous flux passing through the optical fibers of the sensor 1. Measurements of the photocurrent with the help of photodiode 8 and amplifier 9 of the current flow are converted into voltage variations (Fig. 26 ). Using the automatic gain control unit 10, the pulse amplitude voltage is kept constant t / cT, i.e., the amplifier and photodiode are calibrated, and the amplitude of the pulse depth U is determined by the number of sensor optical fibers, i.e. wear friction lining. The signal from the photocurrent amplifier 9 is then inverted by the inverter 11 (Fig. 2c), which makes it possible to measure not the pulse depth, but the amplitude. An indicator 12 is connected to the output of the inverter, which represents a switch instrument of the magnetoelectric system, which measures the constant component of the signal proportional to the amount of wear.

The use of a device for measuring and monitoring the wear of friction linings for an automated research system for bench testing of brakes will improve the performance of life tests.

Claims (1)

Invention Formula A device for measuring and monitoring the wear of friction linings, comprising a linear wear sensor, made in the form of a block of parallel-connected elements and installed in a plane parallel to the plane of the normal section of the friction lining, and a control device, characterized in that, in order to extend the functionality by measuring and control metallized plates, the sensor is made in the form of a block of optical fibers, the input and output ends of which are connected together, and the control device is made in the form of a mule tivibratora, to both outputs of which are connected two LEDs mounted opposite input ends of the optical fibers of the sensor and the calibration waveguide, and the output ends of all optical fibers are connected together and are installed in front of the photodiode connected to an amplifier of the photocurrent and the block automatic gain control, and the output amplifier photocurrent is connected to an indicator. but and. CPUS. 2 g P.