Abstract: Engine anti-idling and restart may be implemented in a machine having a power source, a movable work tool, a pump driven by the power source, an actuator receiving fluid from the pump and moving the work tool, a high-pressure fluid reservoir, and an assist motor operatively connected to the power source. Engine restart may include detecting operator input to start the power source, and fluidly connecting the fluid reservoir to the assist motor to assist in starting the power source in response to detecting the operator input. Prior to shutting down the power source during anti-idling, fluid from the pump may be input to the assist motor, pressurized and communicated to the high-pressure fluid reservoir in response to determining that idle condition exists and a reservoir charge pressure is less than a reservoir minimum restart pressure needed to restart the power source.

Abstract: An energy recovery system for a machine having a movable work tool, a swing motor to swing the work tool about a vertical axis, a pump providing pressurized fluid to the swing motor, a power source outputting power to drive the pump, and a controller. The energy recovery system may include a first accumulator, a swing charge valve selectively connecting the swing motor to the first accumulator, an assist motor operatively connected to the power source, and a discharge selectively connecting the first accumulator to the assist motor. The swing charge valve may fluidly connect the swing motor to the first accumulator when fluid pressure from the swing motor is greater than a charge set pressure. The controller may cause the discharge valve to fluidly connect the first accumulator with the assist motor when the power demand on the power source is greater than a minimum assisted power demand.

Abstract: Swing kinetic and boom potential energy may be recovered in a machine having a movable work tool, a swing motor for rotating the work tool, a hydraulic cylinder for raising and lowering the work tool, a pump selectively connected to the swing motor and the hydraulic cylinder, and a power source outputting power to drive the pump. The machine may further include a first accumulator, a swing charge valve having a charge set pressure, and a boom charge valve. The swing charge valve selectively fluidly connect the swing motor to the first accumulator, and open to fluidly connect the swing motor to the first accumulator when a swing motor fluid pressure is greater than a charge set pressure of the swing charge valve. The boom charge valve may selectively fluidly connect a head-end chamber of the hydraulic cylinder to the first accumulator when the work tool is lowered.

Abstract: A hydraulic control system is disclosed for use in a machine. The hydraulic control system may have a work tool, a motor configured to swing the work tool, a tank, a pump configured to draw fluid from the tank and pressurize the fluid, and a control valve operable to control fluid flow from the pump to the motor and from the motor to the tank via first and second chamber passages to affect motion of the motor. The hydraulic control system may also have an accumulator, and an accumulator circuit configured to selectively direct fluid discharged from the motor to the accumulator for storage and to direct stored fluid from the accumulator to the motor to assist the motor. The hydraulic control system may further have a selector valve configured to selectively connect a higher pressure one of the first and second chamber passages with the accumulator, and a single pressure relief valve disposed within the accumulator circuit and configured to relief pressure from opposing sides of the motor.

Abstract: A system to diagnose a health of a hydraulic accumulator is provided. The hydraulic accumulator includes a first fluid chamber, a second fluid chamber, and a separator. The hydraulic accumulator has an associated pre-charge pressure. The system further includes a pressure sensor, a fluid source, a data processor, and a comparator. The pressure sensor and the fluid source are connected to the first fluid chamber. The data processor is configured to determine a first and second rate of pressure changes, and a transition pressure between the first and second rates. The approximate pre-charge pressure is determined based on the transition pressure. The comparator is configured to compare at least one of the determined pre charge pressure and the frictional forces with a pre-determined threshold range of pre-charge pressure and the frictional forces associated with the hydraulic accumulator to diagnose the health of the hydraulic accumulator.

Abstract: A hydraulic control system for a machine is disclosed. The hydraulic control system includes a pump configured to pressurize a fluid, and a swing motor selectively driven by pressurized fluid from the pump. The swing motor is configured to move a part of the machine. The hydraulic control system also includes a controller in communication with the pump. The controller is configured to receive an input indicative of a difference between a desired speed and an actual speed of the swing motor, and determine if the swing motor is accelerating, decelerating, or operating at neutral mode. The controller is configured to determine an amount of return fluid from an actuator of the machine that is available as makeup fluid for the swing motor if the swing motor is operating at neutral mode. The controller is configured to control the pump based on at least the amount of return fluid.

Abstract: An energy recovery system is disclosed for use with a hydraulic machine. The energy recovery system may have a tank, a pump configured to draw fluid from the tank and pressurize the fluid, an actuator, and an actuator control valve movable to direct pressurized fluid from the pump to the actuator and from the actuator to the tank to move the actuator. The energy recovery system may also have a motor mechanically connected to a rotary device and configured to selectively receive fluid discharged from the actuator, and at least one valve movable to selectively redirect fluid exiting the motor back to the actuator.

Abstract: A hydraulic system includes a hydraulic actuator, a pump configured to supply fluid to the hydraulic actuator, and a first accumulator fluidly connected to the hydraulic actuator. The first accumulator is configured to store fluid received from the hydraulic actuator. The hydraulic system also includes a motor drivingly connected to the pump and fluidly connected to the first accumulator. The motor is configured to receive the stored fluid from the first accumulator to drive the pump. The hydraulic system further includes a first discharge valve fluidly connected between the first accumulator and the hydraulic actuator. The first discharge valve is configured to supply the stored fluid from the first accumulator to the hydraulic actuator without the stored fluid from the first accumulator circulating through the pump.

Abstract: A hydraulic control system for a machine is disclosed. The hydraulic control system may have a pump configured to pressurize fluid, and a motor driven by a flow of pressurized fluid from the pump. The hydraulic control system may also have a first accumulator configured to receive pressurized fluid discharged from the motor and to selectively supply pressurized fluid to the motor, and a second accumulator configured to receive pressurized fluid discharged from the motor and selectively supply pressurized fluid to the motor.

Abstract: A hydraulic system is disclosed for assisting starting of a machine having an engine. The hydraulic system may include a work tool, a pump driven by the engine to pressurize fluid, and an actuator configured to receive pressurized fluid from the pump and move the work tool. The hydraulic system may also include an accumulator configured to selectively receive pressurized fluid from the pump and from the actuator, an electric starter configured to start the engine, and a motor selectively supplied with fluid from the accumulator to assist the electric starter in starting the engine.

Abstract: A hydraulic system is disclosed for assisting starting of a machine having an engine. The hydraulic system may include a work tool, a pump driven by the engine to pressurize fluid, and an actuator configured to receive pressurized fluid from the pump and move the work tool. The hydraulic system may also include an accumulator configured to selectively receive pressurized fluid from the pump and from the actuator, an electric starter configured to start the engine, and a motor selectively supplied with fluid from the accumulator to assist the electric starter in starting the engine.

Abstract: An implement system is disclosed for use with a machine having an engine. The implement system may have a pump driven by the engine, a first actuator configured to receive pressurized fluid from the pump during operation of the engine, and at least a second actuator configure to receive pressurized fluid from the pump during operation of the engine. The implement system may also have an accumulator configured to receive pressurized fluid from the first actuator during operation of the engine, and to discharge fluid to the first actuator and to the at least a second actuator when the engine is shut down.

Abstract: A hydraulic control system is disclosed for use with a machine. The hydraulic control system may have a tank, a pump, a swing motor, and at least one control valve configured to control fluid flow between the pump, the swing motor, and the tank. The hydraulic system may also have an accumulator configured to selectively receive pressurized fluid discharged from the swing motor and selectively supply pressurized fluid to the swing motor, at least one accumulator valve, and a controller. The controller may be configured to receive input indicative of a difference between desired and actual speeds of the swing motor, and determine if the swing motor is accelerating or decelerating based on the difference. The controller may also be configured to control the at least one accumulator valve to cause the accumulator to selectively receive or supply pressurized fluid only when the swing motor is accelerating or decelerating.

Abstract: A method and system for accumulating and using recovered hydraulic energy that includes a hydraulic actuator and a pump configured to supply pressurized fluid to the hydraulic actuator. An energy recovery system includes a hydraulic motor, a charge valve and an accumulator configured to store fluid from the hydraulic actuator. The charge valve is operatively connected between the hydraulic actuator and the accumulator and between the accumulator and the hydraulic motor and is configured to place the hydraulic actuator in fluid communication with the accumulator and to place the accumulator in fluid communication with the hydraulic motor. A directional valve is operatively connected between the pump and the hydraulic actuator. The directional valve is configured to place the pump in fluid communication with the hydraulic actuator and to direct the flow of hydraulic fluid exiting the hydraulic actuator to the charge valve in an energy recovery mode.

Abstract: An energy recovery retrofit kit for a hydraulic control system is disclosed. The energy recover retrofit kit may have a first accumulator and a second accumulator. The energy recover retrofit kit may also have a recovery valve block fluidly connectable between an existing pump and an existing motor of the hydraulic system. The recovery valve block may be configured to selectively fluidly communicate the first and second accumulators with the existing motor.

Abstract: A hydraulic control system for a machine is disclosed. The hydraulic control system includes a pump configured to pressurize a fluid, and a swing motor selectively driven by pressurized fluid from the pump. The swing motor is configured to move a part of the machine. The hydraulic control system also includes a controller in communication with the pump. The controller is configured to receive an input indicative of a difference between a desired speed and an actual speed of the swing motor, and determine if the swing motor is accelerating, decelerating, or operating at neutral mode. The controller is configured to determine an amount of return fluid from an actuator of the machine that is available as makeup fluid for the swing motor if the swing motor is operating at neutral mode. The controller is configured to control the pump based on at least the amount of return fluid.

Abstract: A hydraulic system having an actuator having a piston and associated rod forming head and rod chambers and being adapted to move between retracted and extended positions within a cylinder, and first and second sources of fluid. A first pump provides fluid from the first source to the head chamber at a first pressure. At least one valve provides fluid from the second source at a second pressure to supplement fluid provided to the head chamber from the first pump when the second pressure is greater than the first pressure.

Abstract: A system including a hydraulic accumulator, a pressure sensor, a fluid source and a data processor to detect a pre-charge pressure is provided. The hydraulic accumulator includes first and second fluid chambers and a separator therebetween. The hydraulic accumulator has an associated pre-charge pressure. The pressure sensor is connected to the first fluid chamber. The data processor is connected to the pressure sensor. The data processor is configured to determine a first and second rate of pressure changes, and a transition pressure between the first and second rates. The approximate pre-charge pressure is determined based on the transition pressure.

Abstract: An energy recovery retrofit kit for a hydraulic control system is disclosed. The energy recover retrofit kit may have a first accumulator and a second accumulator. The energy recover retrofit kit may also have a recovery valve block fluidly connectable between an existing pump and an existing motor of the hydraulic system. The recovery valve block may be configured to selectively fluidly communicate the first and second accumulators with the existing motor.

Abstract: A hydraulic system includes a hydraulic actuator, an accumulator, an accumulator charge valve, and a hydraulic transformer fluidly connected between the accumulator charge valve and the accumulator. The hydraulic transformer includes a transformer motor mechanically coupled to a transformer pump. The accumulator charge valve is fluidly connected between the transformer motor and the hydraulic actuator. The transformer pump is sized to permit a maximum flow therethrough of no more than three-quarters of a flow permitted through the transformer motor.