Sensor devices

A sensor device for measuring frequency and amplitude of a varying force signal the sensor device, consisting of:—

• (i) a sensing element defined by a plurality of even numbered planar segments symmetrically disposed about a central axis, each of the segments being responsive to the frequency and amplitude of said varying signal and ambient noise signals associated with the said varying signal, the said segments connected in pairs to each other about the said central axis, such that the segments form discrete sets, said sets responding equally in magnitude but opposite in direction to the said noise signal and said sets responding differentially to the said varying signals to generate noise cancelled output signals, proportionate to the frequency and amplitude of the said varying signal;
• (ii) protective housing for housing the said sensing element, the said housing defined by side walls, an operative base and cover, the said sensing element being fitted to the base of housing;
• (iii) interface element comprising:—
• a) a pick up member for picking up the said varying signals, the said pick up member being centrally disposed with respect to the said central axis of the said sensing element;
• b) a planar mechanical actuator adapted to deform in response to the said varying signal, the said actuator cooperating with the sensing element;
• c) a transfer member adapted to receive varying signals from the pick up, amplify the signals picked up and transfer the amplified signals to the said mechanical actuator;
• and
• (iv) leads for transmitting said output signals outside the sensing device for processing.