Hydraulic pressure transducer with electrical output

Claim 1

A hydraulic transducer comprising a support base including means adapted for connection to a hydraulic input line, a Bourdon tube of generally arcuate configuration mounted to said support base, linkage means connected to said tube to provide rotational motion about a first axis disposed internally of said arcuate configuration as a function of flexure of said tube, shutter means connected to said linkage means to rotate in a plane about said first axis, support means fixedly mounted to said support base on one side of said shutter means, a generally cylindrical enclosure mounted to said support base and including an end cover removably carried in fixed position adjacent and substantially parallel to said shutter means on a side thereof remote from said support means, light emitting means and light responsive means mounted on opposite sides of said shutter means in alignment on a second axis parallel to said first axis at a first radial distance from said first axis, the periphery of said shutter means in said plane having at least a first portion at a radial distance from said first axis which is greater than said first distance and a second portion at a radial distance from said first axis which is less than said first distance, one of said light emitting means and said light responsive means being mounted on said support means and the other of said light emitting means and said light responsive means being mounted on said end cover.