SU1397714A1 - Contactless roughness indicator for checking microgeometry of electric machine commutators - Google Patents

Abstract

The invention relates to a measurement technique and can be used to control the microgeometry of collectors of electric machines. The aim of the invention is to enhance the functionality of the profilometer. The input signal of the primary converter 1 is measured by the measuring circuit 2 and is fed to the inputs of the key control unit 3 and the keys 4 and 5 as a sequence of pulses. In addition, the signal is fed to the inputs of the imaging unit 6 and the controlled filter 8. At the output of the inverter 7, the voltage — the frequency appears voltage proportional to the frequency of the pulses fed to its input from the imaging unit 6. The output from the converter 7 control em cutoff filter 8, the output of which is a signal proportional to the envelope from the output of the measuring circuit 2. When measuring the maximum differences between adjacent plates of the collector pulses come through a bipolar switch 11 on the input rows of elements 12 and 13 of memory, wherein determining modulation difference unit 14 determines the absolute value of their difference. The specified signal arrives at the peak detector 15, which stores the maximum value, and the recorder 16 captures it. When measuring the maximum magnitude of the beating of the collector profile, the inputs of the memory elements 12 and 13 are connected by a bipolar switch 11 through valves of opposite polarity 9 and 10 to the output of the controlled filter 8. In this case, the memory elements 12 and 13 store the amplitude values of the positive and negative parts, respectively the envelope of the measuring signal during one revolution of the box. The maximum value of this signal from the output of the peak detector 15 characterizes the value of the common collector beats. The control unit 17 sets the profilometer to its initial state. 1 il. (L 00; about vj 1 14)

Description

The invention relates to a measuring technique, can be used to control the microgeometry of collectors of electrical machines and is an improvement of the device according to the author. St. No. 1163136.

The purpose of the invention is to expand the functional capabilities of the profilometer by providing the ability to measure the maximum magnitude of the beating jrophil of the collector.

The drawing shows a block diagram of the device.

: The profilometer consists of a primary 5 displacement transducer 1, a measuring circuit 2, a Key management unit 3, two keys 4 and 5, a 6 rectangular pulse former, a frequency transducer 7 - voltage, a 20 low frequency controlled filter 8. Two gates 9 and 10, a bipolar switch 11, two memory elements 12 and 13, a signal difference detection unit 14, a peak detector 25, a recorder 16 and a control unit 17.

The primary displacement transducer 1, for example, of the eddy current type, is installed above the collector of the test machine and connected to the input of the measuring circuit 2, the output of which is connected to 1 with the inputs of keys 4 and 5, unit 3 of the control unit, forming 6 pr pulses and a controlled {low-pass filter 8. The output of block 3 is connected to the control inputs of keys 4 and 5, and the output of the imaging unit 6 is connected to the input of the converter 7 frequency - voltage, the output of which is connected to the control input of the low-frequency filter 8.

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The outputs of the keys 4 and 5 are connected to the inputs of the elements 12 and 13 of the memory through the normally closed contacts of the bipolar switch 11. Normally open contacts of the switch 11 are connected via oppositely connected valves to the output of the controlled filter 8. The outputs of the memory elements 50 are connected to the inputs of the block 14 determining the difference signal module, the output of which is connected to the input of the peak detector 15. The detector output is connected to the recorder 16, and the control 55 inputs of the detector 15 and the memory elements 12 and 13 are connected to the control unit 17.

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The profilometer works as follows.

The output signal of the primary transducer 1 displacement, proportional to the distance between the primary transducer and the monitored surface of the rotating collector, is extracted by measuring circuit 2, amplified by it and in the form of a sequence of pulses from the collector plates enters the inputs of keys 4 and 5 and the input of the key control unit 3, which generates narrow pulses from a sequence of pulses of the measuring signal and in turn supplies them to the control inputs of the keys. In addition, the signal from the output of the measuring circuit 2 is fed to the inputs of the imaging unit 6 and the controlled filter 8. The pulses at the output of the imaging unit have a rectangular shape and a constant amplitude. The magnitude of the DC voltage at the output of the frequency converter 7 is the voltage proportional to the frequency of the pulses fed to its input, and therefore to the frequency of rotation of the core of the electric machine under test. The output signal from the converter 7 controls the cutoff frequency of the low-pass filter 8. The cut-off frequency at a certain frequency of rotation of the core is chosen such that filter 8 enters the signal envelope from the output of measuring circuit 2.

When measuring the maximum differences between adjacent collector plates, narrow pulses from the outputs of keys 4 and 5, whose amplitudes are equal to the amplitudes of the pulses of the measuring signal, through normally closed contacts of the bipolar switch 11. Go to the inputs of memory elements 12 and 13. The memory elements memorize the amplitude values of the pulses of the measuring signal for the time from each previous pulse to each subsequent pulse and form two step signals. These signals from the outputs of elements 1 2 and 1 3 of the memory are fed to the inputs of block 14, which determines the absolute value of their difference, forming a signal proportional to the value of relative differences between adjacent plates. This signal is fed to a peak detector 15, which stores its maximum value corresponding to the maximum difference between

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gray plates collector, and the recorder 16 captures this signal value.

When measuring the maximum magnitude of the total beat of the collector profile, the inputs of the memory elements 12 and 13 are connected by a bipolar switch 11 through valves of oppositely connected valves 9 and 10 to the output of the low-frequency controlled filter 8. In this case, the memory elements 12 and 13 remember the amplitude values of the positive and negative portions of the envelope of the measurement signal, respectively, for the time of one revolution of the core. The signal from the outputs of the memory elements is fed to the inputs of block 14, which determines the absolute value of the difference, forming a signal proportional to the total beating of the collector profile. Peak detector 15 stores the maximum value of the total collector beating and the recorder 16

captures this signal value,

The control unit 17 resets the signals of the elements 12 and 13 of the memory and the peak detector 15 to zero after the end of the measurement, in order to prepare

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We contactless profilometer to a new dimension.

Claims (1)

Invention Formula Contactless profilometer to control the microgeometry of collectors of electrical machines according to ed. St. No. 1163136, characterized in that, in order to extend the functionality by allowing the maximum magnitude of the beating of the collector profile to be measured, it is equipped with a chain of square-mounted square pulse generator, frequency-voltage converter and controlled low-frequency filter, two-pole switch, two valves, the output of the controlled low-frequency filter is connected via oppositely connected valves and normally open contacts of a two-pole switch connected to the input The elements, the memory, the input of the square pulse generator and the second input of the controlled low-frequency filter are connected to the output of the measuring circuit, and the outputs of the keys are connected to the corresponding normally closed contacts of the bipolar switch.