Patent ID: 8544264

Claim:
A hydraulic circuit, comprising: a hydraulic cylinder comprising a head side and a rod side, an accumulator, and a bi-directional variable displacement hydraulic pump positioned fluidly between the head side and both of the rod side and the accumulator to manage flow therebetween, the pump comprising a piston unit rotatable about a piston unit axis, a swashplate associated with the piston unit and movable about a displacement axis to vary displacement of the pump, and a flow distributor configured to control the timing of distribution of flow between a piston of the piston unit and the head side, the rod side, and the accumulator during rotation of the piston unit about the piston unit axis achieving a torque balance on the swashplate about the displacement axis, the flow distributor comprising a distributor head port fluidly connected to the piston unit and the head side, first and second distributor rod ports fluidly connected to the piston unit and the rod side, and a distributor accumulator port fluidly connected to the piston unit and the accumulator, the distributor accumulator port is positioned between the first and second distributor rod ports, the distributor head port has a flow area substantially equal to a cumulative flow area of the distributor accumulator port and the first and second distributor rod ports, the distributor head port has substantially equal flow areas on opposite sides of the displacement axis, the distributor accumulator port has substantially equal flow areas on opposite sides of the displacement axis, and the first distributor rod port and the second distributor rod port are of substantially equal flow area and are positioned on opposite sides of the displacement axis and opposite sides of the distributor accumulator port.