Monolithic accelerometer with flexurally mounted force transducer

Claim 1

An accelerometer for measuring acceleration up to a predetermined full-scale input acceleration, the accelerometer comprising a monolithic crystalline substrate, the substrate comprising: a support; a proof mass; at least one proof mass flexure connecting the proof mass to the support such that the proof mass can rotate with respect to the support about a hinge axis in response to acceleration directed along a sensitive axis normal to the hinge axis; a force transducer having a longitudinal force sensing axis that is parallel to a pendulous axis, the pendulous axis being normal to the hinge axis and to the sensitive axis, the force transducer being characterized by a predetermined relationship between applied force and output frequency, said relationship including a second order nonlinearity; and a transducer flexure connecting the second end of the transducer to the proof mass, the transducer flexure having a thickness substantially less than the thickness of the transducer such that when the proof mass rotates with respect to the support, the transducer rotates with respect to the proof mass about a transducer axis that passes through the transducer flexure, the transducer axis being offset from the hinge axis in a direction along the pendulous axis, said offset being selected so as to reduce said nonlinearity between applied force and frequency.