Variable displacement fluid transducer

Claim 2

A variable displacement fluid transducer comprising: rotatable shaft means; a cylindrical piston barrel joined for rotation with said shaft means; first and second sets of radial pistons, with each set comprising nine uniformly sized piston balls positioned for reciprocation within cylinder bores spaced uniformly around said barrel, said sets of pistons arranged on said barrel to define nine pairs of piston balls; a piston chamber defined in said barrel for each pair of piston balls so that radial reciprocation of said pair of balls displaces fluid from the associated piston chamber; first and second cam tracks circumscribing said first and second sets of pistons, respectively; each of said tracks including four uniformly positioned cam lobes projecting inwardly toward said barrel in frictional engagement with the balls of one set of pistons and shaped to reciprocate the engaged piston balls with a cycloidal motion so that the relative rotation of said barrel with respect to said tracks orbits said balls into engagement with the cam lobes and reciprocates said balls radially to operate said transducer with a fluid displacement from said piston chambers having a substantially uniform flow through said transducer proportionate to the relative reciprocating movement of the balls comprising each pair; control means to move said cam tracks to shift the circumferential alignment of said lobes on said first track with respect to the lobes on said second track to vary the fluid displacement of the transducer by changing the relative reciprocating movement of the balls comprising each pair; and fluid porting means for directing fluid sequentially to and from each of said piston chambers during the operation of said transducer.

Claim 3

A transducer in accordance with claim 1 wherein said cam tracks are arcuate in cross-section with a radius of curvature larger than the radius of the engaged piston balls and further wherein the center of curvature of said cam tracks is spaced axially inwardly from the center of the engaged piston balls So that the reaction force of said balls on said tracks urges said tracks together and thereby assists in maintaining the tracks in an axially stationary position.

Claim 4

A variable displacement fluid transducer comprising: rotatable shaft means; first and second sets of radial pistons, with each set comprising nine uniformly sized piston balls positioned for reciprocation within cylinder bores spaced uniformly around said barrel; said sets of pistons being arranged on said barrel to define pairs of piston balls; a piston chamber extending through said barrel for each pair of piston balls so that radial reciprocation of said pairs of balls displaces fluid from the associated piston chamber; first and second axially aligned cam tracks circumscribing said barrel in radial alignment with said first and second sets of pistons, respectively; each of said tracks including four uniformly shaped and positioned cam lobes projecting inwardly toward said barrel in frictional engagement with the balls of the aligned set of pistons and shaped to reciprocate the engaged piston balls with a cycloidal motion so that the relative rotation of said barrel with respect to said tracks orbits said balls into engagement with the aligned cam lobes and reciprocates said piston balls radially to thereby operate said transducer with a fluid replacement providing a substantially uniform flow through said transducer proportionate to the relative reciprocating movement of the balls comprising each pair; control means to shift the circumferential alignment of said lobes on said first track with respect to the lobes on said second track to vary the fluid displacement of the transducer by changing the relative reciprocating movement of the balls comprising each pair; porting means for directing fluid sequentially to and from said piston chambers, said porting means comprising a porting member axially aligned on each side of said barrel and including axial inlet and outlet ports alternately spaced in a uniform circular pattern, with said inlet and outlet ports spaced adjacent said barrel so that rotation of said barrel places each piston chamber in sequential communication with said inlet and outlet ports, said ports and piston balls being further arranged so that said cycloidal motion of said piston balls causes said inlet and outlet ports to open to said piston chambers at a rate which increases faster than the increase in speed of reciprocation of said piston balls; and fluid collector means in fluid communication with said inlet and outlet ports for directing fluid to said inlet ports and receiving fluid displaced from said outlet ports.

Claim 5

A variable displacement fluid transducer comprising: rotatable shaft means; first and second sets of radial pistons, with each set comprising nine uniformly sized piston balls positioned for reciprocation within cylinder bores spaced uniformly around said barrel; said sets of pistons being arranged on said barrel to define pairs of piston balls; a piston chamber extending through said barrel for each pair of piston balls so that radial reciprocation of said pairs of balls displaces fluid from the associated piston chamber; first and second axially aligned cam tracks circumscribing said barrel in radial alignment with said first and second sets of pistons, respectively; each of said tracks including four uniformly shaped and positioned cam lobes projecting inwardly toward said barrel in frictional engagement with the balls of the aligned set of pistons and shaped to reciprocate the engaged piston balls with a cycloidal motion so that the relative rotation of said barrel with respect to said tracks orbits said balls into engagement with the aligned cam lobes and reciprocates said piston balls radially to thereby operate said transducer with a fluid replacement providing a substantially uniform flow through said transducer proportionate to the relative reciprocating movement of the balls comprising each pair; control means to shift the circumferential alignment of said lobes on said first track with respect to the lobes on said second track to vary the fluid displacement of the transducer by changing the relative reciprocating movement of the balls comprising each pair; porting means for directing fluid sequentially to and from said piston chambers, said porting means comprising a porting member axially aligned on each side of said barrel and including axial inlet and outlet ports alternately spaced in a uniform circular pattern, with said inlet and outlet ports spaced adjacent said barrel so that rotation of said barrel places each piston chamber in sequential communication with said inlet and outlet ports, said ports and piston balls being further arranged so that said cycloidal motion of said piston balls causes said inlet and outlet ports to open to said piston chambers at a rate which increases faster than the increase in speed of reciprocation of said piston balls; and fluid collector means in fluid communication with said inlet and outlet ports for directing fluid to said inlet ports and receiving fluid displaced from said outlet ports.

Claim 6

A fluid transducer in accordance with claim 3 wherein the cross-sectional area of said piston chambers and said inlet and outlet ports is substantially the same and the inlet and outlet ports are spaced alternately so that each rotating piston chamber closes an inlet port and opens the successive outlet port substantially simultaneously.

Claim 7

A fluid transducer in accordance with claim 4 wherein said porting members include four inlet and four outlet ports.