Linear motion power cylinder

Claim 1

A linear motion power cylinder for selective activation by a fluid under pressure, said linear motion power cylinder comprising: an outer cylindrical shell; a cylinder contained within said outer shell, said cylinder defining a cylinder bore within said cylinder having an interior surface; a first port and a second port located at opposite ends of said outer shell for selective connection to a source of pressurized fluid, said first and second ports being connected in fluid communication to the cylinder bore by fluid passage means extending generally longitudinally within said outer shell; a rotor, said rotor having an axis of rotation, and said rotor being rotatably mounted within said cylinder bore such that said rotor may rotate about said axis of rotation, said cylinder and said rotor defining one or more fluid chambers between said cylinder and said rotor in fluid flow communication with said fluid passage means, said rotor further defining an aperture extending substantially longitudinally through said rotor and surrounding said axis of rotation; impeller means mechanically associated with said rotor for imparting rotary motion thereto; a power screw, said power screw being rotatably mounted and having a longitudinal axis of rotation, said power screw further having a threaded region containing one or more threads, said power screw extending substantially through said aperture in said rotor and being received substantially therein; a cylinder rod, said cylinder rod being slidably mounted within said cylinder for linear movement along a longitudinal axis generally parallel to said axis of rotation of said power screw, said cylinder rod further having a threaded segment threadedly engaged with at least a portion of said threaded region on said power screw, such that rotation of said threaded region of said power screw will cause linear movement of said cylinder rod into and out of said aperture of said rotor such that said cylinder rod may be received substantially within said aperture; coupling means mechanically connecting said rotor to said power screw, such that the rotary motion of the rotor is transmitted and imparted to said power screw causing said power screw and said threaded region on said power screw to rotate, whereby fluid may enter the cylinder bore through one of the ports and exit the cylinder bore through the other port, with pressure from the fluid within the cylinder bore causing the rotor to rotate about the axis of rotation, the rotation of the rotor being transmitted by the coupling means to the power screw causing the power screw to rotate; and said outer cylindrical shell, with said first and second ports therein, having overall dimensional specifications conforming substantially to the uniform dimensional specifications for fluid-actuated power cylinders assigned by the National Fluid Power Association, whereby said power cylinder may be compatibly interchanged with dimensional fluid power cylinders conforming to such dimensional specifications.