LOW FREQUENCY VIBRATION TABLE Russian patent published in 1994 - IPC

FIELD: testing of seismometric instrumentation. SUBSTANCE: low frequency vibration table has a movable system connected through a suspension to the base installed on foundation, vibration meter, oscillation exciters connected through immovable parts to the base and through movable parts to movable system, amplifier and reference generator. Foundation is connected to the soil through elastic members. Seismic transformer is installed on the foundation in such a manner, that its sensitivity axis is directed along the axis of generated oscillations. Force detectors linked through immovable part to the soil and through immovable one to the foundation are introduced, as well as the first and the second filters, the second amplifier and integrator. The first and the second filter inputs are connected to the seismic transformer output. The second amplifier input is connected to the output of the first filter, and its output is connected to inputs of force detectors. The first, second and third integrator inputs are connected to outputs of vibration meter, reference generator and the second filter correspondingly. Output of the integrator is connected to input of the first amplifier. EFFECT: increased accuracy when reproducing oscillations. 1 dwg