Hydroacoustic transducer with centering means

Claim 1

A HYDROACOUSTIC DEVICE COMPRISING (A) A HOUSING HAVING A CAVITY THEREIN, (B) A VALVING MEMBER DISPOSED IN SAID CAVITY, MOVEABLE ABOUT A CENTER POSITION, (C) MEANS INCLUDING A FIRST PATH IN SAID HOUSING FOR PASSING FLUID UNDER PRESSURE THROUGH SAID CAVITY UNDER THE CONTROL OF SAID VALVING MEMBER FOR ESTABLISHING ACOUSTIC VIBRATIONS, (D) SAID VALVING MEMBER AND THE WALLS OF SAID CAVITY DEFINING AT LEAST ONE CHAMBER, (E) IMPEDANCE MEANS IN A SECOND PATH IN SAID HOUSING COMMUNICATING WITH SAID CHAMBER FOR THE FLOW OF FLUID INTO AND OUT OF SAID CHAMBER, (F) SAID IMPEDANCE MEANS INCLUDING A FLUID LINE HAVING AN ACOUSTIC IMPEDANCE HIGHER THAN THAT OF SAID VALVING MEMBER AT THE FREQUENCY OF VIBRATION OF SAID VALVING MEMBER, AND (G) SAID VALVING MEMBER AND SAID WALLS OF SAID CAVITY DEFINING AT LEAST ONE ORIFICE FOR CONTROLLING THE FLOW OF FLUID TO SAID ONE CHAMBER SO THAT MOTION OF SAID VALVING MEMBER WITH RESPECT TO SAID CENTER POSITION AT A FREQUENCY LOWER THAN THE FREQUENCY OF SAID ACOUSTIC VIBRATIONS RESULTS IN A PRESSURE VARIATION IN SAID CHAMBER, WHICH PRESSURE VARIATION URGES SAID VALVING MEMBER TO SAID CENTER POSITION.