Variable positive displacement fluid motor/pump apparatus

A positive displacement fluid motor/pump apparatus, comprising:

• a main housing;
• a main shaft rotatably mounted within the main housing for rotation about a main axis;
• two opposing annular cylinder barrels encircling the main shaft at axially spaced locations along the main axis;
• each of the annular cylinder barrels having a plurality of corresponding piston cavities formed therein with each piston cavity having a fluid port communicating therewith to permit flow of fluid to and from the piston cavity;
• a plurality of piston rod assemblies extending axially in opposite directions along the main shaft between the axially spaced annular cylinder barrels at angularly and radially spaced locations about the main axis;
• each piston rod assembly having a piston at an end thereof projecting into a corresponding piston cavity;
• means for maintaining the pistons axially stationary with respect to the main axis;
• two opposing barrel carrier assemblies mounted within the main housing for receiving and rotatably supporting corresponding annular cylinder barrels at the axially spaced locations along the main shaft to enable the annular cylinder barrels to rotate in annular paths coaxially about barrel axes that intersect the main axis at the axially spaced locations along the main axis with the barrel axes and the main axis lying in a common axial plane;
• said annular barrel carrier assemblies having fluid passageway means formed therein for communicating with the fluid ports of the piston cavities to permit fluid to flow through the fluid passageway means and fluid ports to and from the piston cavities;
• said annular barrel carrier assemblies having barrel tilting means for stationarily supporting the annular barrel carrier assemblies to prevent their rotation about the main axis and for enabling the annular barrel carrier assemblies to tilt the opposing barrels about tilt axes that transversely intersect the barrels and countersect the main axis and the barrel axis at the axially spaced locations along the main axis to cause the barrels to rotate in varying elliptical orbital paths centered with respect to the main axis to vary the axial movement of the piston cavities with respect to the axially stationary pistons as the main shaft rotates to vary the amount of fluid flowing to and from the piston cavities;
• and
• torque transfer means operatively interconnecting the cylinder barrels and the main shaft for transmitting rotation therebetween to provide a positive displacement fluid motor/pump apparatus.