Abstract: A vibrating force sensor comprising a metallic strip having three metallic coplanar beams (20, 21, 22). The sensor also includes capacitive transducers (30, 31) for driving the beam or beams into flexural vibration in a plane normal to their common plane and for detecting changes in the frequency of vibrations in response to changes in tension applied to the sensor. Drive and detect electrodes (50, 51) are formed on the surface of an intermediate insulating layer (70) in turn located on the surface of a shielding layer (71) of conductive material.

Abstract: A piezoelectric beam structure for a vibrating beam force sensor in which three coplanar beams of piezoelectric material are spaced side by side and supported between respective common mountings at either end. The two outer counterbalancing beams in operation flex in opposite phase to the center main beam, with each beam flexing in a direction normal to the beam plane. A force sensor which includes this piezoelectric beam structure.