Articulated Drive Shaft

An articulated drive shaft for transferring torque and thrust loads comprising:

• a. a central elongate driven member, said driven member having an upper and lower end, said driven member having a central bore, said driven member having holes into said central bore for pressure compensation, wherein said upper and lower ends of said driven member have internal threaded attachment surfaces;
• b. ball members having a spherical end and an elongate shaft end, said elongate shaft end of said ball member having an external threaded attachment surface threadably engaged with said internal threaded attachment surfaces of said upper and lower ends of said driven member, wherein said spherical ends of said ball members extend outward from said upper and lower ends of said driven member;
• c. ball sockets having a ball containing end slidably surrounding containing each said spherical end of said ball members and an internally threaded end;
• d. upper and lower cylindrical driver members having externally threaded surfaces threadedly attached to said internal threaded attachment surface of said ball sockets;
• e. a plurality of pockets arranged around the internal periphery of each said ball socket between said ball members and said ball socket;
• f. a plurality of rollers arranged in sliding communication within said pockets between said ball sockets and said ball members, wherein said rollers correspond to said pockets for transmission of torque;
• g. internal sealing rings contained within each said ball socket between said upper and lower cylindrical drivers and said spherical ends of said ball members, said internal sealing ring having a concave face wherein said spherical end of said ball member is in sliding communication within said concave face of said internal sealing ring in said ball socket;
• h. a sealing gasket upon said internal sealing ring, wherein said sealing gasket is in sealed communication with said bail socket;
• i. at least one spring upon each said internal sealing ring between said internal sealing rings and said upper and lower cylindrical drivers, wherein said spring provides a constant force upon said sealing ring to engage said concave face upon said spherical end of said ball member, wherein the constant force of said spring creates a seal between said sealing gasket of said sealing ring and said ball socket and said concave face of said sealing ring and said spherical end of said ball member;
• j. lubrication passages in fluid communication with said central bore, said lubrication passage traversing each said upper and lower cylindrical driver members, each said internal sealing rings, and each said ball members;
• k. grease fittings incorporated into each said lubrication passages of each said upper and lower cylindrical drivers for lubrication of said lubrication passages;
• l. opposing pistons within said central bore of said driven member, wherein said pistons are arranged upon either side of said holes of said driven member, said pistons being in fluid communication between said holes of said driven member and said lubrication passages, wherein said piston moves under fluid pressure entering said central bore through said holes to move lubricant through said lubrication passages;
• and
• m. a piston sealing element upon said piston between said piston and said driven member.