Patent ID: 7124576

Claim:
A hydraulic energy intensifying circuit for a work vehicle, the work vehicle including a frame, a tool, a linkage between the frame and the tool, a boom between the frame and the tool, a hydraulic cylinder to manipulate the tool, the hydraulic cylinder having a first chamber and a second chamber, the hydraulic cylinder extending against a first load under an application of a first volume of fluid at a first pressure to the first chamber, the hydraulic cylinder retracting under a second load and an application of a second volume of fluid at a second pressure to the second chamber, a first chamber reaction pressure being produced in the first chamber when the hydraulic cylinder is retracting, the hydraulic energy intensifying circuit comprising: a hydraulic pump to displace the first volume of fluid at the first pressure and the second volume of fluid at the second pressure, the hydraulic pump having a pump inlet; at least one displacement control valve to direct the first volume of fluid to the first chamber to extend the cylinder rod and the second volume of fluid to the second chamber to retract the cylinder rod on demand, the at least one displacement control valve capable of blocking fluid flow from the first chamber; an accumulator capable of storing a predefined volume of fluid from the first chamber of the hydraulic cylinder under an accumulator reaction pressure, the predefined volume being determined when the hydraulic cylinder is in an extended position, the accumulator being pre-charged to a first pre-charge pressure that allows the predefined volume of fluid to be stored in the accumulator when the second volume of fluid at the second pressure is applied to the second chamber in combination with the second load; at least one accumulator valve to allow the predefined volume of fluid from the first chamber to be stored in the accumulator, the at least one accumulator valve allowing the fluid stored in the accumulator under the accumulator reaction pressure to be released from the accumulator, the at least one displacement control valve directing the second volume of fluid from the hydraulic pump to the second chamber and blocking the fluid flow from the first chamber to, thereby, divert the fluid flow from the first chamber to the at least one accumulator valve, the at least one accumulator valve opening to allow the predefined volume of fluid from the first chamber to be stored in the accumulator, the accumulator storing the predefined volume of fluid at the accumulator reaction pressure.