SU402797A1 - DEVICE FOR MEASURING THE ABSORPTION OF ULTRASOUND - Google Patents

Description

The invention relates to the field of instrumentation and may find application in various fields of science and technology.

The differential and compensation devices for measuring the absorption of ultrasound are known to have a non-linear static characteristic, which makes the measurement process difficult.

In order to linearize the static characteristic in the compensation cell of the proposed device, a parallel-movable screen is used, which is kinematically connected with the executive motor of the tracking system.

Schematically, the device shown in the drawing.

On opposite sides of the piezoelectric transducer 1, there are working 2 and compensating 3 ultrasonic cells, reflecting screens 4, 5 of which are located at different distances from the piezoelectric transducer.

In the reflection-ion cell filled with an exemplary liquid, the reflecting screen 5 is made parallel-movable and connected to the output shaft of the actuator b using a gear 7. These elements are combined structurally into an ultrasonic sensor unit 8.

The error amplifier of the tracking system 9 includes a high-frequency generator 10, a high-frequency amplifier 11, selector stages 12, 13, separating the signals of the working and compensation cells, the next 5 carrier frequency amplifier 14.

The circuit 15 for synchronization and selection of signals from the working and compensation cuvette contains an asymmetrical multivibrator 16 probe pulses, a single vibrator 17 of the selector pmpulse delay, and a single vibrator

18selective pulse signal of the working cell. To extract the compensation cell signal, the circuit contains a single vibrator.

19 selector pulse, one-shot 20 5 time delay, following time selector 21.

The device works as follows. A piezoelectric transducer 1, a generator 10, a self-exciting multivibrator 16, forms sounding ultrasound pulses that are emitted simultaneously into working 2 and co-sensational 3 cells.

Passed working and compensatory

cuvette ultrasonic pulses are returned to the solvent converter 1 at different times:

for the working cell, the delay is constant, for

compensatory is variable and determined

position of parallel movable screen

5. (To select a signal with a variable delay, in contrast to the schemes with fixed

the reflectors use the following time selector 21, which is activated by the one-shot 20, after extracting the signal from the working cell).

Two sequences of electrical pulses characterize the attenuation of ultrasound in working 2 and compensatory 3 cells.

By the circuit 15 for synchronization and selection of signals from both cuvettes, both sequences of pulses by selector stages 12, 13 are separated, converted into opposite-polar DC signals. After the amplifier 14, their difference enters the control winding of the engine 6. The latter, together with the gearbox 7, moves the reflecting screen 5 in parallel until this difference becomes zero. The position of the reflective screen 5 estimate the absorption in the working cell.

Subject invention

A device for measuring the absorption of ultrasound, containing its piezoelectric transducer, operating and compensating ultrasonic cells located on opposite sides of the piezoelectric transducer, with reflective screens at different distances from the piezoelectric transformer, an electromechanical tracking system, characterized in that, in order to linearize the static characteristics, a parallel-movable screen is applied in the compensation cell, which is kinematically connected with the executive motor tracking system.