Kazuyoshi Iida

Vibration absorbing apparatus

A vibration absorbing apparatus for reducing vibrations of a vibration damping objective comprises a vibration member excited by a piezo-ceramic element. The voltage applied to the piezo-ceramic element is controlled in accordance with the vibration state of the objective.

Vibration isolating support device

A vibration isolating device comprises a base, a plurality of support members each placed onto the base and comprised of a two series layer of an electroviscous body and an elastomeric body, and a cradle supported through these support members. These support members are provided with circuit for applying voltage to each electroviscous body, respectively.

Sound wave control device

Disclosed herein is a sound wave control device which is shaped in a lens form or a prism form from an acoustically rigid porous material, wherein numerous paths having different path lengths are provided and the apparent medium density is varied. This second wave control device is used to improve the sound quality and the directivity of the sound waves from a speaker and the directional control of noises.