Accelerometer

Claim 1

AN ACCELEROMETER COMPRISING A BASE, MEANS FOR SECURING THE BASE TO AN OBJECT TO BE VIBRATED FOR VIBRATING THE BASE IN ACCORDANCE WITH THE VIBRATIONS OF THE OBJECTS, A SUBSTANTIALLY CIRCULAR DISC-SHAPED ARMATURE CENTRALLY SUPPORTED BY THE BASE AND FLEXED ABOUT ITS CENTER TOWARD AND AWAY FROM THE BASE IN ACCORDANCE WITH THE VIBRATIONS IMPARTED TO THE BASE, A THIN PIEZOELECTRIC ELEMENT PROVIDED WITH ELECTRODES ON THE FACE THEREOF AND SECURED IN FACE ABUTTING RELATION TO THE ARMATURE AND STRESSED IN ACCORDANCE WITH THE FLEXING OF THE ARMATURE FOR PRODUCING ELECTRICAL OUTPUT SIGNALS AT THE ELECTRODES IN ACCORDANCE WITH SAID VIBRATIONS, A HOUSING SEALED TO THE BASE AND HAVING A SUBSTANTIALLY CYLINDRICAL CAVITY ENCLOSING AND SUBSTANTIALLY CONCENTRICALLY ENCOMPASSING THE ARMATURE WITH AN ANNULAR SPACE BETWEEN THE PERIPHERY OF THE ARMATURE AND THE HOLDING, AND A VISCOUS DAMPING LIQUID FILLING THE CAVITY ABOUT THE ARMATURE AND FLOWING THROUGH SAID ANNULAR SPACE BETWEEN THE PERIPHERY OF THE ARMATURE AND THE HOUSING AS THE ARMATURE IS FLEXED BY SAID VIBRATIONS FOR DAMPING THE FLEXING MOVEMENT OF THE ARMATURE, THE RATIO OF THE AREA OF THE ARMATURE TO THE AREA OF SAID ANNULAR SPACE BETWEEN THE PERIPHERY OF THE ARMATURE AND THE HOUSING BEING WITHIN THE APPROXIMATE RANGE OF 3:1 TO 4:1 TO PROVIDE AN UNLOCKED BUT RESTRAINED LAMINAR FLOW THROUGH THE ANNULUS SPACE FOR PRODUCING OPTIMUM DAMPING AND SUBSTANTIALLY CONSTANT ELECTRICAL OUTPUT SIGNALS PER VIBRATION FORCES OVER A WIDE RANGE OF VIBRATION FREQUENCIES.