Hermetically sealed displacement sensor apparatus

摘要

A hermetically sealed displacement sensor has strain gauges placed on thin flexible triangular shaped beams of a load beam cell. The strain gauges are enclosed in a hermetically sealed cavity which cavity is sealed by means of a cover plate placed over the load beam cell. The thin beams are connected together by a center hub and basically form two constant moment beams. There is a top isolation diaphragm member which is convoluted and to which a force is applied which applied force is transmitted to the thin flexible beams. The beams deflect and the sensors produce an output proportional to strain. The sensors on each beam are two in number wherein one sensor is placed in a longitudinal direction with respect to the beam while the other sensor is in a transverse position. The sensors may be wired to form a full Wheatstone bridge or half bridges may be employed. The electrical output from the strain gauge bridge is proportional to the deflection of the center of the sensor.