SU1665228A1 - Oscillating motion meter - Google Patents

Abstract

This invention relates to instrumentation technology. The purpose of the invention is to improve accuracy by reducing the error in the presentation of measurement results. The device consists of an interferometer 2, a photodetector 3, a accumulating adder 5, a display unit 6, a generator 7, a vibrator converter 9 and a frequency divider 10. The number of pulses from the photodetector 3 is measured for N periods of vibration displacement. The number of pulses is multiplied by M using the adder 5. 1 Il.

Description

The invention relates to measuring technique and can be used to control the amplitude of the vibration.

The purpose of the invention is to increase the accuracy of 5 by reducing the error in the presentation of measurement results.

The drawing shows a block diagram; meter.

The meter consists of optically coupled 10 monochromatic light sources 1, an interferometer 2 and a photodetector 3, serially connected to the driver amplifier 4, the input of which is connected to the output of the photodetector 3, 15 of the accumulating adder 5 and display unit 6, connected in series to the generator 7, amplifier 8 and a vibration transducer 9 mechanically coupled to the interferometer 2, a frequency divider 10, the input 20 of which is connected to the output of the generator 7 and the counter 11, the counting input of which is connected to the transfer output of the adder 5, and the output d is connected to the second input unit 6, the control inputs of the adder 5, November 25 and the counter unit 6 connected to the output of the divider 10.

The vibration displacement meter works as follows.

Monochromatic radiation from the source 30 I of the nickname 1 enters the interferometer 2, into which; The optical difference in the radiation path is modulated by a vibration transducer 9, (connected through an amplifier 8 to a generator 7. Interfering rays from an interferometer 35 meters 2 enter the photodetector 3 and I amplifier-driver 4, the output of which is a pulse signal corresponding to the alternation of dark and light interference Each of these pulses provides the addition of the integer - the conversion factor M. to the contents of the accumulating adder 5. Due to the fact that the transfer output of the accumulating adder 5 is 45 dynamin with the counter input of counter 11 at the outputs of the accumulating adder 5 and counter 11 together forms an integer M times the number of pulses appearing at the output of amplifier 4. This number 50 is indicated by the indicating unit 6. The output signal of the generator 7 is fed to the counting input of the frequency divider 10 having a division coefficient N. The output signal of the frequency divider 10 provides a record of '55 along its leading edge of the measurement results from the information outputs of the accumulating adder 5 and counter 11 in the display unit 6, as well as resetting uplifting adder 5 and counter 11. Thus, the frequency divider 10 provides a measurement cycle for N periods of the signal of the generator 7, i.e. the number N determines the measurement time. During the measurement cycle at the inputs of the display unit 6, a number equal to ¹⁴ Λ / 4 'is formed where A is the amplitude of the oscillations, microns;

λ is the wavelength of the monochromatic light source, microns;

N is the division ratio of the frequency divider;

M - integer - conversion factor received at the information inputs of the accumulating adder;

K is the number received at the information inputs of the display unit from the information outputs of the counter and the accumulating adder and indicated by the display unit.

It follows that ^{2 A} = 10 ^K N · M

To obtain the measurement results in a convenient form, it is necessary that the ratio

- ^ 4r = 10 “ ⁿ (1 ± d), N · M ⁴ 'where η is an integer;

d - permissible relative error associated with the accuracy of the representation of wavelength A.

Then the range of vibration displacement is determined by the formula

2Α = Κ · 10Λ

To select the numbers N and M, it is convenient to use the factorization of integers in the range Λ / 4 10 ^p (1 ± d).

For example, for a helium-neon laser used as a monochromatic light source, λ / 4 = 0.1582 μm.

There is a decomposition of 1582 = 2 · 7 · 113, which makes it possible to use the values of Ν, M given in Table. 1, with g = 0.

Bearing in mind the decomposition 1581 = 3 * 17 »31, one can use the values of Ν, M given in Table. 2, while 0 = 1/1582 = 0.06%.

Table 1

N M 2 791 7 226 14 113 113 14 226 '7 791 2

table 2

N M 3 527 17 93 31 51 51 31 93 17 527 3

Claims (1)

Claim A vibration displacement meter containing optically coupled monochromatic light source, an interferometer and a photodetector, an amplifier driver, the input of which is connected to the output of the photodetector, a generator and a frequency divider connected in series, a vibration transducer whose input is electrically connected to the generator output, the vibration transducer is mechanically connected 5 to the interferometer sequentially connected * counter and display unit, the control inputs of which are connected to the output of the frequency divider, characterized in that then, in order to improve accuracy, 10 it is equipped with an accumulating adder, the input of which is connected to the output of the driver amplifier, the transfer output is connected to the counter input of the counter, the counter is made two-input, the counting output of the accumulating adder is connected to the second input 15 of the counter, the control input of the accumulating adder is connected to frequency divider output.