Patent ID: 9746005
Date: 2017-08-29
CPC Classifications: F15B

Claim:
1. A hydraulic control system comprising an actuator having a pair of chambers disposed to apply a motive force derived from fluid within said chambers to move a drive member in opposite directions, each chamber having a variable capacity hydraulic machine associated therewith to control flow in to and out of respective chambers, a control to control operation of said machines and thereby movement of said drive member, said control operating on a first one of said machines to limit the capacity thereof and thereby determine the maximum flow rate from one of said chambers by determining, based at least in part on a command input, a target pressure, which is below a predetermined maximum pressure, of said one chamber, and then adjusting the capacity of the first one of said machines to maintain the target pressure, said controller operating on a second one of said machines to determine a pressure at which fluid is provided to the other of said chambers, and wherein each of said machines comprises a pump-motor that is reversible to permit each of said machines to operate in a pumping mode or a motoring mode, and wherein when one of said machines operates in the pumping mode, the other one of said machines operates in the motoring mode.