MULTI-FUNCTION MACHINES, HYDRAULIC SYSTEMS THEREFOR, AND METHODS FOR THEIR OPERATION

摘要

Systems and methods for controlling and actuating actuators that perform multiple functions in a machine. Such systems and methods encompass a hydraulic system adapted to control and actuate the actuators of the machine. The hydraulic system includes variable displacement pump/motors connected to the engine in parallel. A first of the pump/motors controls a first of the actuators, and a second of the pump/motors is adapted to draw power from and deliver power to the engine and the first actuator, as well as control at least a second of the actuators. An energy storage device is connected in series with the second pump/motor and the second actuator, and accumulates a fluid pumped thereto by the second pump/motor, as well as delivers the fluid to the second pump/motor, depending on whether the second pump/motor delivers is delivering or drawing power from the engine or first actuators.