Abstract: One embodiment of a hydraulic system for a machine has a first hydraulic circuit including a first pump coupled to a first hydraulic actuator configured to move a first implement of the machine. A second hydraulic circuit includes a second pump coupled to a second hydraulic actuator configured to move a second implement. An electric motor mechanically couples to the first pump and to the second pump. An operator interface receives input from an operator requesting movement of the first and second implements. A controller communicatively coupled to the electric motor and to the operator interface determines, based on the requested movement of the first and second implements respectively, first and second flow allocations respectively for the first and second pumps and determines respective target displacements for the first and second pumps.

Abstract: One embodiment of a hydraulic system for a machine has a first hydraulic circuit including a first pump coupled to a first hydraulic actuator configured to move a first implement of the machine. A second hydraulic circuit includes a second pump coupled to a second hydraulic actuator configured to move a second implement. An electric motor mechanically couples to the first pump and to the second pump. An operator interface receives input from an operator requesting movement of the first and second implements. A controller communicatively coupled to the electric motor and to the operator interface determines, based on the requested movement of the first and second implements respectively, first and second flow allocations respectively for the first and second pumps and determines respective target displacements for the first and second pumps.

Abstract: A system can include one or more valve arrangements with a working chamber to receive a working fluid at a first pressure, and a control chamber to receive fluid at a second pressure. A dynamic seal can be disposed on a land of a valve element. A supply passage can be in communication between the control chamber and a tank and can include a check valve. A relief valve can be disposed between the check valve and the control chamber. A pilot pump and another relief valve may be disposed upstream of the check valve. The relief valve downstream of the check valve can have a higher pressure limit than the downstream one. A pressure sensor may be disposed between the check valve and the control chamber and used to warn the operator of a high pressure in the control chamber.

Abstract: A hydraulic control system for a machine is disclosed. The hydraulic control system may have a tank, a pump configured to draw fluid from the tank and pressurize the fluid, an actuator, and a control valve configured to direct fluid from the pump to the actuator and from the actuator to the tank to move the actuator. The hydraulic system may also have a main relief valve movable away from a closed position to pass pressurized fluid to the tank when a pressure of the fluid directed to the actuator exceeds a first threshold pressure, and a controller in communication with the pump. The controller may be configured to selectively reduce a displacement of the pump after the main relief valve has moved away from the closed position when the pressure of the fluid directed to the actuator exceeds a second threshold pressure.

Abstract: A hydraulic control system includes a swing control valve between a pump and a swing motor to control flow to/from the swing motor, and a selector valve between an accumulator and the swing motor to regulate fluid flow. A controller is configured to receive inputs indicative of the pressure differential between the accumulator and conduit between the pump and swing motor, and a swing motor command, calculate a target swing motor flow based on the swing motor command input, and modulate operation of the swing control valve and the selector valve to regulate a swing speed.

Abstract: An independent metering valve (IMV) assembly is disclosed that includes a metering stem including an inlet. The IMV assembly also includes a hydro-mechanical control valve in communication with a fluid source and the inlet. The control valve also including a spool with a closed end and an open end. The control valve includes a biasing member that biases the control valve or spool towards an open position thereby establishing communication between the fluid source and the inlet. The control valve also including a load signal line providing communication between an outlet of the control valve upstream of the inlet and the closed end of the spool. Wherein high pressure in the load signal line allowing the control valve to move towards a closed position thereby overcoming bias of the biasing member and reducing flow to the inlet during a high pressure condition.

Abstract: A hydraulic control system for a machine is disclosed. The hydraulic control system may have a tank, a pump configured to draw fluid from the tank and pressurize the fluid, an actuator, and a control valve configured to direct fluid from the pump to the actuator and from the actuator to the tank to move the actuator. The hydraulic system may also have a main relief valve movable away from a closed position to pass pressurized fluid to the tank when a pressure of the fluid directed to the actuator exceeds a first threshold pressure, and a controller in communication with the pump. The controller may be configured to selectively reduce a displacement of the pump after the main relief valve has moved away from the closed position when the pressure of the fluid directed to the actuator exceeds a second threshold pressure.

Abstract: A control system is disclosed for use with an excavation machine. The control system may have a work tool, an operator input device to receive input indicative of a desired movement of the work tool, at least one actuator, and at least one sensor associated with at least one of the work tool and the at least one actuator. The control system may also have a controller in communication with the operator input, the at least one actuator, and the at least one sensor. The controller may be configured to make a classification of a current operation of the machine as one of a plurality of known operations based on a signal from at least one of the operator input device and the at least one sensor. The controller may be further configured to adjust an operational parameter of the at least one actuator based on the classification.

Abstract: A system can include one or more valve arrangements with a working chamber to receive a working fluid at a first pressure, and a control chamber to receive fluid at a second pressure. A dynamic seal can be disposed on a land of a valve element. A supply passage can be in communication between the control chamber and a tank and can include a check valve. A relief valve can be disposed between the check valve and the control chamber. A pilot pump and another relief valve may be disposed upstream of the check valve. The relief valve downstream of the check valve can have a higher pressure limit than the downstream one. A pressure sensor may be disposed between the check valve and the control chamber and used to warn the operator of a high pressure in the control chamber.

Abstract: A control system for a machine is disclosed. The control system may have a pump, a low pressure reservoir, and at least one actuator connected to receive fluid pressurized by the pump and discharge fluid to the low pressure reservoir. The control system may also have a bypass passage situated to allow fluid to bypass the at least one actuator, and a warmup valve disposed within the bypass passage and being movable between a flow-passing position and a flow-blocking position. The control system may further have a hydraulic temperature sensor configured to generate a signal indicative of a temperature of the fluid, and a controller in communication with the pump, the warmup valve, and the hydraulic temperature sensor. The controller may be configured to move the warmup valve to the flow-passing position, fix a displacement position of the pump, and adjust an input speed of the pump in response to the signal.

Abstract: An independent metering valve (IMV) assembly is disclosed that includes a metering stem including an inlet. The IMV assembly also includes a hydro-mechanical control valve in communication with a fluid source and the inlet. The control valve also including a spool with a closed end and an open end. The control valve includes a biasing member that biases the control valve or spool towards an open position thereby establishing communication between the fluid source and the inlet. The control valve also including a load signal line providing communication between an outlet of the control valve upstream of the inlet and the closed end of the spool. Wherein high pressure in the load signal line allowing the control valve to move towards a closed position thereby overcoming bias of the biasing member and reducing flow to the inlet during a high pressure condition.

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: A method of controlling an electro-hydraulic system having an engine driving a variable displacement pump, a hydraulic valve and a hydraulic actuator in order to achieve more efficient engine operation is disclosed. The pressures in the electro-hydraulic system are monitored and commands are received indicating the desired movement of the hydraulic actuator. Based on the pressure and the commands, the operation being performed by the machine is determined and the engine is set to an efficient setting for the particular segment of machine operation.

Abstract: A hydraulic system for a machine is disclosed. The hydraulic system may have a pump, a tank, a first actuator with a head-end and a rod-end, and a first valve arrangement configured to control fluid flow from the pump to the first actuator and from the first actuator to the tank. The hydraulic system may also have a second actuator with a head-end and a rod-end, and a second valve arrangement configured to control fluid flow from the pump to the second actuator and from the second actuator to the tank. The hydraulic system may further have a third valve arrangement fluidly connected between the first and second valve arrangements to receive pressurized fluid from the pump in parallel with the first and second valve arrangements. The third valve arrangement may be configured to facilitate fluid regeneration of and supplemental flow to at least one of the first and second actuators.

Abstract: A control system for a machine is disclosed. The control system may have a pump, a low pressure reservoir, and at least one actuator connected to receive fluid pressurized by the pump and discharge fluid to the low pressure reservoir. The control system may also have a bypass passage situated to allow fluid to bypass the at least one actuator, and a warmup valve disposed within the bypass passage and being movable between a flow-passing position and a flow-blocking position. The control system may further have a hydraulic temperature sensor configured to generate a signal indicative of a temperature of the fluid, and a controller in communication with the pump, the warmup valve, and the hydraulic temperature sensor. The controller may be configured to move the warmup valve to the flow-passing position, fix a displacement position of the pump, and adjust an input speed of the pump in response to the signal.

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: A method of controlling an electro-hydraulic system having an engine driving a variable displacement pump, a hydraulic valve and a hydraulic actuator in order to achieve more efficient engine operation is disclosed. The pressures in the electro-hydraulic system are monitored and commands are received indicating the desired movement of the hydraulic actuator. Based on the pressure and the commands, the operation being performed by the machine is determined and the engine is set to an efficient setting for the particular segment of machine operation.

Abstract: The present disclosure is directed to a hydraulic system. The system includes a first source of pressurized fluid and at least one fluid actuator. The system also includes a first valve disposed between the first source and the at least one fluid actuator being configured to selectively communicate pressurized fluid from the first source to a source of low pressure. The system further includes a controller configured to determine a first amount of displacement of the first valve, determine a second amount of displacement of the first valve, and modify the first amount of displacement as a function of the second amount of displacement when a first pressure is less than or equal to a pressure of pressurized fluid acting on the at least one fluid actuator.

Abstract: A hydraulic control system for a work machine is disclosed. The hydraulic control system has a fluid actuator, a supply of pressurized fluid, and a control valve movable to selectively pass pressurized fluid to the fluid actuator. The hydraulic control system also has a sensor configured to sense the pressure of the pressurized fluid passed to the fluid actuator and a controller in communication with the control valve and the sensor. The controller is configured to receive an input indicative of a desired velocity of the fluid actuator and to determine a fluid flow rate corresponding to the desired velocity. The controller is also configured to determine a ratio of the sensed pressure to a stall pressure of the supply and to scale down the determined flow rate an amount based on the determined ratio. The controller is further configured to move the control valve an amount corresponding to the scaled down flow rate.

Abstract: A hydraulic system having a source of pressurized fluid and a fluid actuator with a first chamber and a second chamber. The hydraulic system also has a first valve configured to selectively fluidly communicate the source with the first chamber and a second valve configured to selectively fluidly communicate the source with the second chamber. The hydraulic system also has a supply passageway and a signal passageway each disposed between the first and second valves in parallel. The hydraulic system also has a proportional pressure compensating valve configured to control a pressure of a fluid directed between the source and the first and second valves. The hydraulic system further has a fluid passageway disposed between the supply and signal passageways to fluidly communicate the supply and signal passageways.