RESONANT-BEAM ACCELEROMETER WITH ROTATING ARTICULATED LEVER ARM

摘要

The present invention relates to a micro-machined accelerometer that uses a mobile seismic mass (100) suspended with relation to a substrate by elastic links (12, 14) only allowing a translation in its own plane along a sensitive axis (Oy); the mass acts on at least one elongated resonator (20) through a force amplification structure related to that resonator; the amplification structure includes a rigid lever arm (30) having a first end (32) connected to the seismic mass by a link (36) having a high stiffness in the mass plane in the direction of the sensitive axis and a low stiffness in the perpendicular direction, and a second end (34) connected to an anchoring point (A6) on the substrate. The second end (34) of the lever arm is a rigid head part surrounding the anchoring point (A6) and connected to said anchoring point by a link (38, 40) capable of rotation about a rotation centre (M); the resonator has one end attached to the rigid head part at point (B) so that the longitudinal axis of the resonator extends at a distance h from the centre of rotation (M) of the rotating link that is less than the length L of the lever arm but different from zero.