SU1348661A1 - Device for measuring amplitude and frequency of oscillations - Google Patents

Abstract

This invention relates to a measurement technique. The aim of the invention is to improve the measurement performance in the area of infrasonic frequencies due to the possibility of simultaneous measurement of the amplitude and frequency of oscillations. A device for measuring the amplitude and frequency of oscillations contains a source of radiation 1, the beam from which hits the oscillating surface of an object, is reflected from Phie, / it, and hits the lens 2, which moves the object to the photocathode of a transmitting television tube. . The projected image is transmitted to the television monitor 4, where it is displayed on the screen in an enlarged form on some line. The horizontal shaper 6 generates a pulse corresponding to the given line, the vertical shaper 8 determines the instant of reference for the duration of the information pulses. The received information pulses go to the analog-to-digital converter 10, where they are converted into digital form, and then to the calculator 11, where the maximum the duration of the pulses during the oscillation period of the object and with its help the oscillation amplitude value is calculated, and the period between the maximum duration is determined pulses, which corresponds to the oscillation frequency. 2 Il. i with 4U 00 О5 О5 pp

Description

The invention relates to a measurement technique and can be used to measure vibrations of an infra-sound frequency.

The aim of the invention is to improve the performance of measurements in the area of infrasonic frequencies due to the possibility of simultaneously measuring the amplitude and frequency of oscillations.

Fig. I is a block diagram of a device for measuring the frequency and amplitude of oscillations; figure 2 - diagram of the optical unit of the device.

The device contains optically coupled radiation source 1, lens 2 and photodetector 3, made in the form of a transmitting television tube, television monitor 4, row selector 5, horizontal former 6, vertical unit 7, vertical former 8, three-input element 9 and analog-to-digital Converter 10 (ADC), calculator 11, amplitude indicator 12 and frequency indicator 13, output of photodetector 3 is connected to the input of television monitor A, the first output of which is connected to the first inputs of line selection block 5, block 7 of vertical and third of tail element 9, the second output is connected with the second inputs of the row selection block 5 and the vertical block 7, the third output is connected with the second inputs of the horizontal horizontal generator 6 and the vertical vertical generator 8, the first input of which is connected with the output of the vertical block 7, the output with the input of the three-input element I 9, the second input of which is connected with the output of the horizontal horizontal array 6, the first input of which is connected with the output of the row selection block 5, the output of the three-input element And 9 connected with the input of the ADC 10 whose output is connected with the input of the calculator 11 first and in Ora outputs of which are associated with the indicator 12 of the amplitude and frequency of the indicator 13 respectively.

The device works as follows.

The beam of the radiation source 1 hits the oscillating surface of the object, which during oscillations can occupy two extreme positions, is reflected from it and hits the lens 2. Lens 2 projects the object's movement onto the photocathode of the transmitting television tube 3 as a segment. Projected image

five

about

five

0

6

It is transmitted to a television monitor 4, where it is displayed on the screen enlarged on a line. Block 5 line selection forms the code of its number, which is supplied to the shaper 6 horizontal. The code change in block 5 of the row selection occurs with the frequency of frame sync pulses. A horizontal sync pulse arrives at one of the inputs of the horizontal shaper 6, and at the output a pulse appears, in its temporal position corresponding to the selected row. This pulse arrives at one of the inputs of the three-input element AND 9. Similarly to the operation of the row selector 5 and the horizontal shaper 6, the vertical block 7 and the vertical shaper 8 operate, the output of which impulse is affected, with a slight delay in relation to the pulse from the output Forming 6 horizontal. This delay corresponds to the position of the selected vertical, from which the pulse duration is measured. The impulse from the output of the vertical imager 8 unlocks the element 9 and the information signal from the output of the television monitor 4 enters the ADC 10, where it is converted into digital form and then enters the calculator 11, In the latter, the maximum duration of the pulses during the oscillation of the object is determined by the formula

one

1 K-B F

(-p) .n:

0

five

0

five

where K is the transmittance of the optics;

F is the focal length of lens 2;

B is the distance from the axis of the radiation source 1 to the axis of the lens 2;

n is the length of time corresponding to the passage of the photoflo from the center of the tube 3 to the beginning of the video pulse by the scanning beam;

1 - the length of time corresponding to the maximum duration of the video pulse. The amplitude value is highlighted on the amplitude indicator 12. The period of occurrence of the maximum duration of video pulses is also determined by the calculator 11 and corresponds to

oscillation frequency of the object. The frequency value is highlighted on the frequency indicator 13.

Claims (1)

Invention Formula A device for measuring the amplitude and frequency of oscillations, containing an optically coupled radiation source, a lens and a photodetector, a signal processing circuit whose input is connected to the photodetector output, characterized in that, in order to improve performance in the area of infrasonic frequencies, the photodetector is designed as a transmitting device. television tube, the processing circuit is designed as a series-connected television monitor, three-input element And, analog 486614 a digital converter, a calculator and an amplitude indicator connected in series to a row g selection unit and a horizontal former, successively connected vertical block and a vertical former, frequency indicator, the first output of the television monitor is connected to the first The 10 inputs of the row selector and the vertical block, the second output are connected to the second inputs of the row selector and the vertical block, the third output is connected to the second inputs of the horizontal bar and vertical bar, the second and third inputs of the three-input element And are connected to the horizontal bar's outputs and the vertical driver, respectively, the second output of the calculator is connected to the input of the frequency indicator. j j ///////// Compiled by S.Konyukhov Editor E.Kopcha Tehred M.Hodanich Proofreader V.Girn to    - - - - - - - - -. V-V- ------- - -. -.-..- ,. Order 5181/40 Circulation 499 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4