BROADBAND RESONANT SEISMIC AND ACOUSTIC RECEIVER Russian patent published in 2018 - IPC G01V1/16 

FIELD: instrument making.

SUBSTANCE: invention relates to instrument making and can be used both in the field of geophysics for the high-frequency seismic noise recording and the wells acoustic logging and for engineering control over the large structures, as well as over machines and mechanisms units and unit assemblies. Proposed seismoacoustic receiver comprises housing and two mounted therein cantilever-type elastic plates with bimorph transducers, on free ends of which inertial masses are secured in the form of two coils of variable mass from the durable light material, for example, carbon fiber reinforced plastic. One common wire made of a heavy material, for example tungsten, is wound on the coils with the possibility of its rewinding between the coils. Wire rewinding between the coils leads to change in their inertial masses and, as a consequence, to change in the elastic plates resonant frequencies. This will allow to scan the operating frequency band, for which two reversible motor generators are installed in the housing, each of which is connected to first and second coils, respectively, by the flexible drive. They are included into the common electrical circuit with possibility of their coordinated alternately switching from the engine mode to the generator mode and back. Elastic plates material and geometric dimensions are chosen so that with the wire rewinding between the coils their natural frequencies were changing in adjacent frequency bands. Near the support on each elastic plate flat sensing element in the form of a bimorph piezoelectric transducer of rectangular shape is arranged. To the transducer output signal linear dependence on the plate mechanical oscillations amplitude, the elastic plate at the bimorph location is made in the form of an isosceles trapezium, which larger base is clamped into the support, and the plate geometric dimensions are chosen so that to satisfy the relation (a+b)d=ac, where a is distance from the inertial mass fixing point to the trapezoid d smaller base, b is trapezium height, c is the trapezium larger base.

EFFECT: multiple increase in scanning efficiency, which allows to significantly increase the scanning frequency range while reducing the device weight and dimensions.

4 cl, 2 dwg