Apparatus for measuring forces in compression or in tension

Claim 1

IN APPARATUS FOR MEASURING FORCES: A BELLOWS COMPRISING COMPRESSIBLE AND EXTENSIBLE SIDES, A TOP PLATE FOR RECEIVING THE FORCE TO BE MEASURED, AND A BOTTOM PLATE, SAID PLATES SEALED TO SAID SIDES TO DEFINE A FIRST CHAMBER OF VARIABLE CAPACITY; INSTRUMENTALITIES DEFINING A SECOND CHAMBER OF VARIABLE CAPACITY, SAID INSTRUMENTALITIES INCLUDING A BASE AND A COVER, SAID COVER HAVING AN AREA MATERIALLY LESS THAN THAT OF SAID TOP PLATGE; CONDUIT MEANS COMMUNICATING WITH SAID FIRST AND SECOND CHAMBERS; FIRST MEASURING MEANS FOR ACCURATELY DETERMINING A VARIATION IN THE DISTANCE BETWEEN SAID PLATES; A THIRD CHAMBER OF VARIABLE CAPACITY COMMUNICATING WITH SAID FIRST AND SECOND CHAMBERS; AS SUBSTANTIALLY NONCOMPRESSIBLE FLUID FILLING SAID CHAMBERS AND SAID CONDUIT; SAID CHAMBERS, CONDUIT AND FLUID CONSTITUTING A CLOSED HYDRAULIC SYSTEM; MICROMETRIC MEANS FOR INCREASING OR DECREASING THE CAPACITY OF SAID THIRD CHAMBER TO SELECTIVELY FORCE FLUID INTO OR OUT OF THE REMAINDER OF SAID SYSTEM IN ORDER TO ALTER THE DISTANCE BETWEEN SAID PLATES WHEN THE DISTANCE BETWEEN SAID COVER AND BASE IS FIXED, OR TO ALTER THE DISTANCE BETWEEN SAID COVER AND BASE WHEN THE DISTANCE BETWEEN SAID PLATES IS FIXED; AND MEANS FOR APPLYING A MEASURED COMPENSATING FORCE TO SAID COVER THAT WILL SEPARATE SAID PLATES BY THE SAME DISTANCE THAT SEPARATED THEM BEFORE THE FORCE TO BE MEASURED WAS APPLIED TO SAID TOP PLATE, WHEREBY THE MAGNITUDE OF THE FORCE TO BE MEASURED MAY BE DETERMINED BY MULTIPLYING THE MEASURED COMPENSATING FORCE BY THE RATIO