SU1384982A1 - Hybrid optical-fibre instrument transducer of mechanical quantities - Google Patents

Abstract

The invention relates to instrumentation. The purpose of the invention is to improve the accuracy of conversion by increasing the mechanical quality factor of the piezoresonator and noise immunity. The modulated signal from the radiation source 8 is amplified by converting an electric photodetector 5 with an amplifier 4 and inversely converted into an optical radiation source 6 and fed through a light guide 7 to the photodetector 2, where it is converted into a pulsating electric current that induces an emf in the secondary winding of the transformer 1 exciting piezoresonator 3. 1 Il.

Description

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The invention relates to instrumentation and can be used in measurements of mechanical and thermal quantities as a measuring converter.

The aim of the invention is to increase the conversion accuracy by increasing the mechanical quality factor of the piezoresonator and noise immunity.

The drawing shows the proposed device.

The device contains a matching transformer 1, the primary receiver of which includes a photodetector 2, and a secondary transformer includes a piezoresonator 3, made in the form of an acousto-optic modulator with excitation due to its own piezoelectric signal, an amplifier 4 of the photodetector 5, loaded onto a pulsed radiation source 6, connected by a fiber a light guide 7 with a photodetector 2, a radiation source 8 connected by optical fibers 9, 10 through a piezo resonator 3 with a photodetector 5.

The device works as follows.

When oscillating, a piezoresonator 3 is carried out. The optical modulation of the radiation of the source 8. The modulated signal is amplified by converting it into an electrical photoreceiver 3 with an amplifier 4 and converting it back to an optical pulsed radiation source 6 and is fed through the optical fiber 7 to the photoreceiver 2, is converted into a pulsating electric current, which induces in the secondary winding of the transformer 1 a variable EMF exciting the piezoresonator 3. Since the excitation conditions

self-oscillations are performed only near the natural frequency of the piezoresonator, the frequency of self-oscillations practically coincides with the natural frequency of the piezoresonator, which depends on the magnitude of the measured action applied to the resonator.

Due to the absence of an electrical communication line between the power supply and the piezoresonator, the immunity and accuracy of the converter increases.

Claims (1)

Invention Formula Hybrid fiber optic mechanical measuring transducer values, containing a piezoresonator with an optical modulator and a source and the first radiation receiver with an amplifier connected to the optical modulator by optical fibers, from a l and a. This is due to the fact that, in order to increase the conversion accuracy by increasing the mechanical quality factor of the piezoresonator and noise immunity, it is equipped with a pulsed the radiation source, an additional optical fiber, a second radiation receiver and a matching transformer, and the pieorezonator is designed as an acousto-optic modulator with excitation due to its own piezoelectric effect, the second radiation receiver being electrically connected via a matching transformer to the piezoresonator, and optically through an additional optical light guide with a pulse radiation source that is connected to the output of the amplifier of the radiation receiver.