Abstract: This disclosure relates to a hydraulic system and method that converts the kinetic energy generated by the operation of a swing motor into hydraulic potential energy and reuses the hydraulic potential energy for swing motor acceleration. An accumulator can be provided for storing exit oil from the swing motor that is pressurized by the inertia torque applied on the moving motor via movement of an upper structure of a machine. The pressurized oil in the accumulator can be reused to accelerate the swing motor by supplying pressurized oil to the swing motor.

Abstract: An actuator control system is disclosed. The actuator control system may have a pump and at least one actuator. The actuator control system may further have an actuator valve configured to control the at least one actuator. The actuator control system may also have a pump pressure sensor configured to determine a pump pressure value and a load pressure sensor configure to determine a load pressure value. The actuator control system may additionally have a controller configured to receive the pump pressure value and the load pressure value. The controller may further be configured to compare the pump pressure value and the load pressure value, and selectively implement a primary control strategy and a secondary control strategy based on the comparison.

Abstract: A method of calibrating an electrically controlled hydraulic valve having a known relationship between flow rate through the valve and displacement of a valve element is disclosed. The method includes ascertaining a first current level for actuating the electrically controlled hydraulic valve to move the valve element to a position adjacent an inlet port, and a first displacement of the valve element responsive to the first current level. The method also includes ascertaining a second current level for actuating the electrically controlled hydraulic valve to move the valve element from the position adjacent the inlet port to a position permitting flow through the inlet port, and ascertaining a second displacement of the valve element responsive to the second current level. The method further includes establishing a relationship between current and displacement associated with the electrically controlled hydraulic valve.

Abstract: This disclosure relates to a hydraulic system and method that converts the kinetic energy generated by the operation of a swing motor into hydraulic potential energy and reuses the hydraulic potential energy for swing motor acceleration. An accumulator can be provided for storing exit oil from the swing motor that is pressurized by the inertia torque applied on the moving motor via movement of an upper structure of a machine. The pressurized oil in the accumulator can be reused to accelerate the swing motor by supplying pressurized oil to the swing motor.

Abstract: An actuator control system is disclosed. The actuator control system may have a pump and at least one actuator. The actuator control system may further have an actuator valve configured to control the at least one actuator. The actuator control system may also have a pump pressure sensor configured to determine a pump pressure value and a load pressure sensor configure to determine a load pressure value. The actuator control system may additionally have a controller configured to receive the pump pressure value and the load pressure value. The controller may further be configured to compare the pump pressure value and the load pressure value, and selectively implement a primary control strategy and a secondary control strategy based on the comparison.

Abstract: A hydraulic system may include a hydraulic actuator. The hydraulic system may also include a pump having a pump inlet and a pump outlet, and the pump may be configured to supply fluid to the hydraulic actuator. The hydraulic system may further include an energy recovery system operatively connected between the hydraulic actuator and the pump. The energy recovery system may be configured to store fluid from the hydraulic actuator under an overrunning load condition, and the stored fluid may be directed through the pump inlet and into the hydraulic actuator.

Abstract: A hydraulic system may include a hydraulic actuator. The hydraulic system may also include a pump having a pump inlet and a pump outlet, and the pump may be configured to supply fluid to the hydraulic actuator. The hydraulic system may further include an energy recovery system operatively connected between the hydraulic actuator and the pump. The energy recovery system may be configured to store fluid from the hydraulic actuator under an overrunning load condition, and the stored fluid may be directed through the pump inlet and into the hydraulic actuator.