Transducer

Claim 1

A static pressure compensated transducer comprising: a base; first and second cantilever leaf spring beams each having one end fixed relative to said base; means to move the other end of said first beam in a direction approximately normal to the plane Thereof, the other end of said second beam being suspended freely from said base in a stationary position independent of the position and movement of the other end of said first beam; a Wheatstone bridge having first, second, third and fourth legs and first, second, third and fourth conductive corners, said first, second, third and fourth legs being connected between said first and second, second and third, third and fourth, and fourth and first conductive corners respectively, said corners acting as junctions; first and second strain gages fixed to opposite sides of said first beam between the ends thereof and connected in series in said first and second bridge legs, respectively; third and fourth strain gages fixed to opposite sides of said second beam between the ends thereof and connected in series in said third and fourth bridge legs, respectively; means to supply different potentials to said first and third bridge corners; and output means connected from and responsive to a difference of potential between said second and fourth corners to produce an output signal which is a function of the magnitude of the movement of the said other end of said first beam, said base defining a chamber having a fluid therein, both of said beams being fixed to said base in positions extending into the selfsame said chamber and being subjected to the fluid pressure in said chamber, said function being less sensitive to changes in said fluid pressure than it would be were said second beam and said third and fourth strain gages isolated from said chamber.