SU1236311A1 - Induction vibration transducer - Google Patents

Abstract

The invention relates to a measurement technique, can be used to monitor the parameters of vibrations, and improves the sensitivity of an inductive vibration sensor containing two coupled oscillatory circuits, one of which is installed on the test object. The coupling of the oscillatory circuits is the result of the coaxial arrangement of the inductors and the connection of their leads through a coupling capacitor and a resistor. A power supply is connected to the oscillatory circuits through a transformer. A change in the relative position of the inductors induces a change in the inductive coupling between them and leads to a mismatch of the system of oscillatory circuits. As a result, the magnitude and phase of the current consumed from the power source, which is recorded by the measuring unit, changes. The parameters of oscillatory displacements of the control object are determined from its output signal; instantaneous magnitude and deviation sign, amplitude, frequency, etc. Due to the fact that the current of the coupled oscillatory circuits strongly depends on the relative position of the inductors, the sensitivity of the vibration sensor is increased. 1 il. c (O (L tc SA O5 CO

Description

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The invention relates to a measurement technique and can be used to monitor vibration parameters.

The purpose of the invention is to increase the sensitivity of an inductive vibration sensor by increasing the steepness of the total amplitude-frequency characteristic of oscillatory circuits.

The drawing shows a vibration sensor, a general view.

The vibration sensor contains an oscillating circuit 1, made in the form of a fixed inductance coil 2 with a capacitor 3 connected in parallel to it, and an oscillating circuit 4, made in the form of an inductance coil 5 with. connected in parallel with her capacitor 6. Inductance coil 5 is made with the possibility of oscillatory displacements along the longitudinal axis and installed coaxially with coil 2 inductance. A resistor 7 is connected between one pair of outputs of coils 2 and 5, and a coupling capacitor 8 between another pair of their coils. A transformer 9 is connected to the oscillatory circuit 1 by its secondary winding. A measuring unit 10 connected in series, made, for example, in the form of an instantaneous current meter, and a power source 11 are connected to the primary winding of the transformer 9. The natural frequencies of oscillatory: contours 1 and 4 are approximately equal to each other. Inductance coil 2 is fixed

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The vibration displacement of the test object causes the coil 5 to move relative to the equilibrium position, which leads to a change in the inductive coupling of coils 2 and 5 and to periodic changes in the magnitude and phase of the total current of oscillatory circuits 1 and 4 flowing through the secondary winding of the transformer 9. Accordingly, also the magnitude and phase of the current in its primary winding, measured using the measuring unit 10. According to the output signal (or readings) of the measuring unit

 5 10 determine the magnitude and sign of the instantaneous deviation of the control object from its initial neutral position, as well as the integral parameters of the vibration displacements: amplitude, frequency, etc. By adjusting the value of the resistor 7, a linear dependence of the output signal of the measuring unit 10 on the magnitude of the vibration displacement of the inductor 5 in a given range of its movements is achieved. Due to the fact that the total current consumed from the power source is influenced by both coupled oscillatory circuits with changes in the relative position of the inductors, i.e. The slope of the total amplitude-frequency characteristic is increased, the sensitivity of the vibration sensor is increased.

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Claims (1)

Invention Formula An inductive vibration sensor containing a power source and two parallel parallel inductively coupled oscillatory circuits connected to it, made in the form of two coaxially inductors installed coaxially with a con- nector connected to each of them. motionless, and the coil 5 is connected in the process of measurement with the object of control. The vibration sensor works as follows. The source 11 inductively coupled coils 2 and 5 of the oscillatory circuits 1 and 4, under the influence of the forces of the ponderomotive interaction, are set in a position of stable equilibrium at a certain distance from one another. The magnitude of this distance depends on the capacitance of the coupling 8, which is chosen so that the initial equilibrium position of the coil 5 coincides with the initial position of the control object associated with it. ten 36311J The vibration displacement of the test object causes the coil 5 to move relative to the equilibrium position, which leads to a change in the inductive coupling of coils 2 and 5 and to periodic changes in the magnitude and phase of the total current of oscillatory circuits 1 and 4 flowing through the secondary winding of the transformer 9. Accordingly, also the magnitude and phase of the current in its primary winding, measured using the measuring unit 10. According to the output signal (or readings) of the measuring unit  5 10 determine the magnitude and sign of the instantaneous deviation of the control object from its initial neutral position, as well as the integral parameters of the vibration displacements: amplitude, frequency, etc. By adjusting the value of the resistor 7, a linear dependence of the output signal of the measuring unit 10 on the magnitude of the vibration displacement of the inductor 5 in a given range of its movements is achieved. Due to the fact that the total current consumed from the power source is influenced by both coupled oscillatory circuits with changes in the relative position of the inductors, i.e. The slope of the total amplitude-frequency characteristic is increased, the sensitivity of the vibration sensor is increased. thirty 35 Invention Formula a unit characterized in that, in order to increase sensitivity, it is provided with a coupling capacitor connected between one pair of inductors 50, the resistor is connected between the other pair of terminals, the measuring unit is connected in series with the power source, both oscillatory circuits are made 55 with equal natural frequencies and one of the inductors is designed to be installed on the control object.