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Claim 1

A FORCE-RESPONSIVE DEVICE FOR MEASURING THE MAGNITUDE OF A FORCE APPLIED ALONG A GIVEN AXIS, COMPRISING, IN COMBINATION, A CASING SURROUNDING SAID AXIS HAVING AN AXIALLY EXTENDING CAVITY CIRCULAR IN CROSS-SECTION AND OPEN AT ITS UPPER END AND CLOSED AT ITS LOWER END BY A DIAPHRAGM, SAID DIAPHRAGM BEING CONNECTED TO SAID CASING AROUND ITS PERIPHERY AND BEING FREE TO DEFLECT DOWNWARD SO THAT APPLICATION OF A POSITIVE PRESSURE TO THE UPPER FACE OF SAID DIAPHRAGM WILL PRODUCE ON ITS LOWER FACE COMPRESSIVE STRAINS AROUND THE PERIPHERY AND TENSILE STRAINS IN THE CENTRAL PORTION, AN AXIALLY EXTENDING FORCERECEIVING AND FORCE-TRANSMITTING PISTON EXTENDING WITHIN SAID CAVITY THROUGH ITS UPPER OPEN END, SAID PISTON HAVING AN AXIAL SLIDABLE FIT WITH THE WALL OF SAID CAVITY ALONG AT LEAST THE LOWER PORTION THEREOF, A RUBBER-LIKE PRESSURETRANSMITTING PAD DISPOSED BETWEEN SAID PISTON AND SAID DIAPHRAGM AND SUBSTANTIALLY COMPLETELY FILLING THE CAVITY SPACE CONTAINED THERE-BETWEEN SO THAT APPLICATION OF A DOWNWARD AXIAL FORCE TO THE UPPER END OF SAID PISTON CAUSES SAID PAD TO BE SUBJECT TO COMPRESSION STRESS THROUGHOUT ITS VOLUME, THEREBY SUBJECTING THE ENTIRE UPPER FACE OF SAID DIAPHRAGM TO A POSITIVE PRESSURE, MEANS DISPOSED ADJACENT TO THE PERIPHERAL PORTION OF SAID DIAPHRAGM SO THAT THE RUBBER-LIKE ACTION OF SAID PAD IN RESPONSE TO SAID DOWNWARD FORCE CAUSES THE SAID POSITIVE PRESSURE TRANSMITTED BY IT TO SAID DIAPHRAGM, WHEREBY THE RATIO OF THE MAXIMUM COMPRESSIVE STRAIN TO THE MAXIMUM TENSILE STRAIN ON THE LOWER FACE OF SAID DIAPHRAGM IS SMALLER THAN IT WOULD BE IF THE UPPER FACE OF THE DIAPHRAGM WERE SUBJECTED TO A UNIFORM HYDROSTATIC PRESSURE, TWO ELECTRICALLY RESPONSIVE STRAIN GAGE MEANS ATTACHED TO SAID DIAPHRAGM SO THAT ONE IS RESPONSIVE TO THE COMPRESSIVE SURFACE STRAINS OF THE DIAPHRAGM WHILE THE OTHER IS RESPONSIVE TO SIMULTANEOUS TENSILE SURFACE STRAINS THEREOF, BOTH STRAINS RESULTING FROM THE BENDING OF SAID DIAPHRAGM IN RESPONSE TO SAID DOWNWARD FORCE, SAID GAGES BEING CONNECTABLE TO PROVIDE A SINGLE CUMULATIVE RESPONSE TO AN APPLIED FORCE.