Patent ID: 7204160

Claim:
An apparatus for testing the material properties of a specimen, said apparatus comprising: a top joint movable along a longitudinal axis of said apparatus, said top joint having a first sleeve capable of rotation about the longitudinal axis with said first sleeve having at least two arms extending radially outward and longitudinally to a first end of said first sleeve, and said top joint having a second sleeve adjacent to the first end of said first sleeve, said second sleeve having at least two arms extending radially outward and longitudinally to the first end of said first sleeve; a bottom joint including a first sleeve having at least two arms extending radially outward and longitudinally to a first end of said first sleeve of said bottom joint and having a second sleeve adjacent to the first end, said second sleeve having at least two arms extending radially outward and longitudinally to the first end of said first sleeve of said bottom joint; a first linkage for enclosing the specimen, said first linkage having a first, second, third and fourth oblong bars, a first link between said first and second bars and a second link between said third and fourth bars wherein said first bar links to one arm of said first sleeve of said top joint and said third bar links to another arm of said first sleeve of said top joint and wherein said second bar links to one arm of said second sleeve of said bottom joint and said fourth bar links to another arm of said second sleeve of said bottom joint; a second linkage for enclosing the specimen, said second linkage having a first, second, third, and fourth oblong bars, a link between said first and second bars and a second link between said third and fourth bars wherein said first bar links to one arm of said second sleeve of said top joint and said third bar links to another arm of said second sleeve of said top joint and wherein said second bar links to one arm of said first sleeve of said bottom joint and said fourth bar links to another arm of said first sleeve of said bottom joint; a plurality of loading plate assemblies, each of said loading plate assemblies pivotally attached with a yoke at a first end to each of said links of said first and second linkages with said yoke including arms extending on opposite sides of a longitudinal axis of said yoke and slidable within a frame exterior to said yoke with an end of said frame extending to a clamp attachable to the test specimen such that said loading plate assemblies enclose the specimen in opposing pairs where each of said loading plate assemblies and said arms movably connected to a distal end of a piston affixed at a proximate end to said frame, wherein said arms slide within said frame to control motion of said clamp to said yoke such that a test load is imparted to the specimen; and a pressure system fluidly connected to impact opposite faces of said piston such that one of said opposite faces is pressurized and therefore impacts said arms for the sliding motion along the longitudinal axis of said yoke.