Meterless hydraulic system having flow sharing and combining functionality

A hydraulic system comprising:na variable-displacement first pump;a variable-displacement second pump;a first actuator selectively connected either to the first pump in a closed loop manner and not the second pump, or to the first and second pumps in a closed loop manner;a second actuator selectively connected either 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; anda variable-displacement rotary actuator selectively connected either to the first pump in a closed loop manner and not the second pump, or to the first and second pumps in a closed loop manner.

A hydraulic system comprising:na variable-displacement first pump;a variable-displacement second pump;a first actuator connected to the first pump in a closed loop manner;a second actuator selectively connected to the second pump in a closed loop manner;a variable-displacement rotary actuator selectively connected to the first pump in a closed loop manner;a combiner valve arrangement configured to:nselectively connect and disconnect the second pump from the first actuator and the rotary actuator, andselectively connect and disconnect the first pump from the second actuator; andat least one switching valve fluidly connected to at least one of the first actuator, the second actuator, or the rotary actuator, the at least one switching valve being configured to control an amount of fluid passing through a first actuator passage and a second actuator passage connected to the at least one of the first actuator, the second actuator, or the rotary actuator.

A method of operating a hydraulic system, the method comprising:npressurizing fluid with a first variable-displacement pump;pressurizing fluid with a second variable-displacement pump, the first and second pumps being capable of simultaneously supplying pressurized fluid to at least three actuators, the at least three actuators including a variable-displacement rotary actuator, a linear actuator, and a third actuator;selectively controlling whether to direct fluid pressurized by the first pump and the second pump to only one of the at least three actuators, to only two of the at least three actuators simultaneously, or to three of the at least three actuators simultaneously;returning the pressurized fluid to the first and second pumps in a closed-loop manner;adjusting displacement of the rotary actuator to control torque output of the rotary actuator; andmetering the flow passing between the first and second pumps and the linear actuator to control movement of the linear actuator.