TORSIONAL GEOPHONE Russian patent published in 1997 - IPC

FIELD: measurement of torsional vibrations of ground medium and determination of parameters of torsional motion of various building structures and their members. SUBSTANCE: the offered geophone has body of ferromagnetic material and coil for formation of output signal with body rotating in magnetic field (for instance, in Earth magnetic field) and the second coil positioned at angle of 90 deg to the first coil. Ferromagnetic body is cubic in shape. Introduction of the second coil allows obtaining signal at its output shifted by phase through π/2 relative to signal from the first coil and realizing of computing operation of type , where E₁ and E₂ are values of electromotive force induced in the first and second coils, respectively, as a result of which linear output characteristic is formed within the entire range of change of angular parameters. EFFECT: higher efficiency. 3 dwg