Patent ID: 8677886

Claim:
A hydraulic system comprising: a source of pressurized fluid; a hydraulic actuator; a first chamber configured to expand and contract, wherein expansion of the first chamber actuates the actuator in a first direction; a first pressure reducing valve fluidly connected between the first chamber and the source; a second chamber configured to expand and contract, wherein expansion of the second chamber actuates the actuator in the first direction, the second chamber being substantially hydraulically isolated from the first chamber; a second pressure reducing valve fluidly connected between the second chamber and the source; a third chamber configured to expand and contract, wherein expansion of the third chamber actuates the actuator in a second direction, the second direction being opposite to the first direction; a third pressure reducing valve fluidly connected between the third chamber and the source; a fourth chamber configured to expand and contract, wherein expansion of the fourth chamber actuates the actuator in the second direction, the fourth chamber being substantially hydraulically isolated from the third chamber; and a fourth pressure reducing valve fluidly connected between the fourth chamber and the source.