METERLESS HYDRAULIC SYSTEM HAVING FLOW SHARING AND COMBINING FUNCTIONALITY

摘要

A hydraulic system (56) includes a variable-displacement first pump (68A, 68B, 68C, 68D) and a variable-displacement second pump (68A, 68B, 68C, 68D). The hydraulic system also includes a first actuator (26, 32, 34) selectively connected either to the first pump in a closed loop manner and not the second pump, to the second pump in a closed loop manner and not the first pump, or to the first and second pumps in a closed loop manner. The hydraulic system further includes a second actuator (26, 32, 34) selectively connected either to the first pump in a closed loop manner and not the second pump, to the second pump in a closed loop manner and not the first pump, or to the first and second pumps in a closed loop manner. The hydraulic system also includes a variable- displacement rotary actuator (43, 42R, 42L) selectively connected either to the first pump in a closed loop manner and not the second pump, to the second pump in a closed loop manner and not the first pump, or to the first and second pumps in a closed loop manner.