SU120852A1 - Device for converting low-frequency mechanical oscillations of a tongue-type resonator into electrical ones - Google Patents

Description

A device is proposed for converting low frequency mechanical vibrations into electrical ones.

Known transducers of mechanical oscillations into electrical ones are based on the use of ferroelectric, capacitive sensors or galvanic contact devices. A disadvantage of the known transducers is the difficulty of taking readings, the violation of the source’s own resonant frequency is oscillated by 1I, or the need to use complex electronic circuits with the converter.

The proposed device facilitates the reading of indications without disturbing the natural resonant frequency of the source of oscillations, which distinguishes it from the known ones.

FIG. 1 is a diagram of the proposed device; in fig. 2 - scheme of multi-channel low-pass filter.

The device consists of the excitation coil 1 with the iron heart, the permanent magnet 2, the metal tab 3 with the hole 4, the light source 5, the photodiode 6, the power source 7 and the resistance of the load 8.

To protect against external light sources, the device is covered by an opaque housing 9.

During iodacation in the coil / electrical oscillations, the alternating magnetic field created by the coil and the constant magnetic field act on the metallic tongue. This forces it to move in the direction of the coil and magnet with an increase in the absolute value of the intensity of the total magnetic field and in the opposite direction as the total intensity decreases. the floor

If the frequency of the alternating magnetic field coincides with the natural frequency of the mechanical oscillations of the tongue, the amplitude of the mechanical oscillations will be maximum.

In order to convert mechanical vibrations into electrical tongs, 3 has an opening 4, the shape of which is determined by a predetermined form of electrical oscillations of the converter. To obtain sinusoidal oscillations, the hole must be in the form of an equilateral triangle and positioned so that, in the absence of an alternating magnetic field, the center of the triangle is on the line connecting the light source 5 and the photodiode 6. Vibrations of the tongue 3 lead to a displacement of the ptr.rgtia 4 from the horpine yutpr source and din diode, as a result of which the luminous flux incident on the photodiode is modulated by the amplitude of the oscillation frequency of the tab. The resistance of the photodiode depends on the efficiency, measure The development of which leads to a change in the current in the circuit: photodiode 6 - power supply 7 - load resistance 8.

Protection of the device against external mechanical effects is ensured by appropriate orientation of the tongue 3 with respect to perturbing mechanical forces or by damping.

The device can be used as a narrow-band low-pass filter.

The multichannel version of such a filter (Fig. 2) consists of a sound generator 10, giving a spectrum of noise frequencies from fi to f of equal amplitude, a coil .11, a magnet 12, a system of tabs 13 with various openings, a source (21). 2, not shown), photodiodes 4, load resistances 15, and power supply 16.

The resonant frequencies of the tabs 13 are different and respectively equal

(L / 2, / 3, A, And / 5). When the generator 10 is operating, at the resistances 15, frequency voltages equal to the frequencies of the tongues oscillate are separated.

Subject invention

A device for converting mechanical oscillations of a low frequency of a tongue-type resonator into electrical ones, which means that, in order to make it possible to use such a resonator as a filter with a narrow bandwidth and as a multichannel low-pass filter, it consists of light sensors that produce light beams, modulated by the openings of the vibrating tongues of the resonator and photocells, at the load resistances of which an electrical signal is emitted with a frequency corresponding to the frequency ezonatora of the tongue.