SU1275363A1 - Method of vibration measuring of gaps in kinematic pairs - Google Patents

Abstract

The invention relates to the field of vibration measurements and can be used for vibration measurements of gaps in kinematic pairs. The aim of the invention is to improve the accuracy by determining the clearance without disassembling the kinematic pair. The acoustic signal of the test object is measured. Transform the signal into electrical. The power distribution over the spectrum is determined. In the kinematic pair, the oscillations generated are random and cover a certain frequency interval, limiting the resolution and accuracy. This is eliminated by integrating the power spectrum of the acoustic signal and detecting the first derivative of the integral curve. The latter is determined by calculating Q (Total unit. Then the gap is determined from the curve, 3 Il, 1 tab. (L

Description

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oo f co 11 The invention relates to the field of vibro-measurements and can be mainly used for vibroism rhenium gaps B of kinematic pairs. The aim of the invention is to improve the measurement accuracy by determining the gap without disassembling the kinematic pair. FIG. 1 shows the power spectrum of an acoustic signal; in fig. 2 - integral curve of the power distribution spectrum; in fig. 3 is a diagram of an apparatus for carrying out the method. The method is carried out as follows. The acoustic signal of the object under study 1 is measured, which is converted into an electrical sensor 2, for example, seismic, passed through a band-pass filter 3, using the average power spectrum meter 4, for example a spectrum analyzer, to determine the power distribution over the spectrum, which is integrated using a histomat 5. Using a histo and a mat, the following operations are carried out: the power spectrum of an acoustic signal is quantized, for example, at points a, b, c, d, e, at a subsequent quantum segment, to the value of din you point spectrum curve about five moschnos added value x predydupr portions. Thus, the coordinate JS (the points in the integral curve will correspond to the coordinate S (u)) are also points b, points c on the integral curve — the sum of the coordinates of points b and c on the coordinate of the power spectrum curve, etc. Using a computing unit 6, for example a histomat prefix 5, an elevation angle o is determined, for example, a derivative of a curve. The value of tgot multiplied by the proportionality coefficient K determines the gap in the recorder 7. In the kinematic pair, the generated oscillations are random and cover a certain frequency interval, for example, uJ. - and) „, which limits the resolution, range of application and accuracy. This is eliminated by integrating the power spectrum of the acoustic signal and detecting the first derivative of the integral curve, equal to u3, J S () duJ tgot Example. We investigated the nodes of rotation of the tape mechanism, on which a seismic sensor 2 of type CD 30-2480 is mounted, connected to a band-pass filter 3 of an FS 4-Vib. Type, the output of which is connected to an average power meter 4, for example a spectrum analyzer of the PANORA-M type CLF-26 (USA) connected to the output of the integrating unit 5 as a histomat and to the computing unit 6, which determines the angle of elevation of the integral curve, and the recorder 7, which determines the size of the gap. Block 6, as well as the recorder 7, are applied in the form of digital blocks of computer complexes of the HewIeH Packard company. Experimental studies were carried out in the private range of 0.05–20 kHz with gaps of 0.02–0.8 mm. The experiment was carried out with 10 kinematic pairs arranged in a circle on a platform with a seismic sensor in the center. Each kinematic pair vibrated separately. The results of the experiment are shown in table-.

0,0150,015 0,015

10.02

0.0200.021 0.021

20.03

0.015 0.020 0.020 0.025 From the table it can be seen that the coefficient of proportionality between the change in cg oi the rise of the integral curve and the change in the size of the gap is 1.3. At 20 kHz, a slight non linearity, which is explained by the fact that this type of sensor worked outside the passport mode. Best linearity at a frequency of 5 kHz which is the center frequency for the sensor. The application of the proposed method improves the accuracy of measuring the gap of the kinematic pair.

Claims (1)

Continued Table The claims of the method of vibration measurements of gaps in kinematic pairs, which consists in measuring the power spectrum of an acoustic signal during the operation of a kinematic pair, characterized in that, in order to improve the accuracy by determining the change in the gap without disassembling the kinematic pair, the power spectrum of the acoustic the signal is quantized on consecutive frequency sites, the quantization results are summarized as an integral curve, the first derivative of which determines m gap. 5 (w) So J ABOUT and S with d e w and (jz Q} {J8.f a 6 cf c ABOUT COf FIG. 2 I, I I f. JI II H. ft} .7 fig.Z