Abstract: Actuators and corresponding methods and systems for controlling such actuators offer efficient, fast, flexible control with large forces. In an exemplary embodiment, an fluid actuator includes a housing having first and second fluid ports, an actuation cylinder in the housing defining a longitudinal axis and having first and second ends in first and second directions, an actuation piston in the cylinder with first and second surfaces moveable along the longitudinal axis, a spring subsystem biasing the actuation piston to a neutral position, a first fluid space defined by the first end of the actuation cylinder and the first surface of the actuation piston, and a second fluid space defined by the second end of the actuation cylinder and the second surface of the actuation piston. A first flow mechanism controls fluid communication between the first fluid space and the first port, whereas a second flow mechanism controls fluid communication between the second fluid space and the second port.

Abstract: An expansion valve for an air conditioning system circulates refrigerant through a fixed-displacement compressor, a condenser, and an evaporator. An inlet is provided for receiving refrigerant liquefied in the condenser. An outlet of the expansion valve supplies refrigerant to the evaporator. A valve element controls flow of refrigerant between the inlet and the outlet, wherein the valve element is normally closed. A control assembly is coupled to the valve element and is responsive to at least one temperature or pressure in the air conditioning system to open the valve element to variably meter the refrigerant to the evaporator. A bleed passage bypasses the valve element to conduct refrigerant between the inlet and the outlet.

Abstract: Actuators, and corresponding methods and systems for controlling such actuators, provide independent valve control with a large initial or opening force.

Abstract: Actuators, and corresponding methods and systems for controlling such actuators, provide independent lift and timing control with minimum energy consumption. In an exemplary embodiment, an electromechanical actuator comprises a housing, first and second electromagnets rigidly disposed in the housing and separated from each other by an armature chamber, an armature disposed in the armature chamber and movable between the first and second electromagnets, an armature rod rigidly connected with the armature and operably connected with a load, at least one first actuation spring biasing the armature in a first direction, at least one second actuation spring biasing the armature in a second direction, and one fluid-operated spring controller capable of controlling the position of the first-direction end of the at least one second actuation spring. The spring controller allows the actuation springs at their least compressed state and the engine valve closed when engine power is off.

Abstract: A thermostatic expansion valve assembly is provided for an air conditioning system. A thermostatic expansion valve includes a valve body having an evaporator inlet port, an evaporator outlet port, a suction line port, and a liquid inlet port. The thermostatic expansion valve controls a flow of refrigerant from the liquid line port to the evaporator inlet port. A liquid line conduit is coupled to the liquid inlet port. The liquid line conduit has at least a segment elevated above the liquid inlet port. The vapor within the liquid inlet conduit accumulates at an uppermost portion of the segment prior to a compressor startup. A substantial amount refrigerant liquid is maintained between the uppermost portion of the segment and the liquid inlet port prior to the compressor startup.

Abstract: Actuators, and corresponding methods and systems for controlling such actuators, provide independent valve control with a large initial or opening force.

Abstract: Actuators, and corresponding methods and systems for controlling such actuators, provide independent valve control with a large initial or opening force.

Abstract: A thermostatic expansion valve includes a valve body having an evaporator inlet port, an evaporator outlet port, a suction line port, and a liquid line port. A sensor chamber formed within the valve body is disposed between the evaporator outlet port and the suction line port. A valve is disposed within the valve body controls a flow of refrigerant from the liquid line port to the evaporator inlet port. A diaphragm separates a charge chamber and a pressure chamber where a pressure differential between a charge chamber and a pressure chamber controls the positioning of the valve. A restriction flow passage located to provide fluid communication between the sensor chamber and the pressure chamber is configured to limit a flow rate from the pressure chamber to sensor chamber, thereby slowing the opening of the valve resulting in a reduction of noise generated following an initial startup of a compressor.

Abstract: Actuators, and corresponding methods and systems for controlling such actuators, provide independent valve control with a large initial or opening force.

Abstract: Actuators and corresponding methods and systems for controlling such actuators offer efficient, fast, flexible control with large forces. In an exemplary embodiment, an fluid actuator includes a housing having first and second fluid ports, an actuation cylinder in the housing defining a longitudinal axis and having first and second ends in first and second directions, an actuation piston in the cylinder with first and second surfaces moveable along the longitudinal axis, a spring subsystem biasing the actuation piston to a neutral position, a first fluid space defined by the first end of the actuation cylinder and the first surface of the actuation piston, a second fluid space defined by the second end of the actuation cylinder and the second surface of the actuation piston; and a flow bypass that short-circuits the first and second fluid spaces when the actuation piston is not proximate to the second end of the actuation cylinder.

Abstract: Improved actuators and valve control systems, and methods for controlling actuators and/or engine valves, are disclosed. In addition to the inherent capability of timing control, the ability to provide continuous valve lift or stroke control greatly improves engine achieve fuel economy, emission and performance. The power-off state of the actuator is at the minimum stroke, from which an easy start-up can be directly executed. The minimum stroke is also very beneficial to achieve efficient low load operation. Even with continuous lift variation, the present invention is able to keep the spring force neutral or zero point in the center of a stroke, thus maintaining an efficient scheme of energy conversion and recovery through the pendulum action. When in compression braking or other high engine cylinder air pressure working mode, the invention is able to supply necessary force to open the engine valve.

Abstract: Actuators and corresponding methods and systems for controlling such actuators offer efficient, fast, flexible control with large forces. In an exemplary embodiment, an fluid actuator includes a housing having first and second fluid ports, an actuation cylinder in the housing defining a longitudinal axis and having first and second ends in first and second directions, an actuation piston in the cylinder with first and second surfaces moveable along the longitudinal axis, a spring subsystem biasing the actuation piston to a neutral position, a first fluid space defined by the first end of the actuation cylinder and the first surface of the actuation piston, and a second fluid space defined by the second end of the actuation cylinder and the second surface of the actuation piston. A first flow mechanism controls fluid communication between the first fluid space and the first port, whereas a second flow mechanism controls fluid communication between the second fluid space and the second port.

Abstract: Actuators, and corresponding methods and systems for controlling such actuators, provide independent lift and timing control with minimum energy consumption. In an exemplary embodiment, an actuation cylinder in a housing defines a longitudinal axis and having first and second ends in first and second directions. An actuation piston in the cylinder, with first and second surfaces, is moveable along the longitudinal axis. First and second actuation springs bias the actuation piston in the first and second directions, respectively. A first fluid space is defined by the first end of the actuation cylinder and the first surface of the actuation piston, and a second fluid space is defined by the second end of the actuation cylinder and the second surface of the actuation piston. A fluid bypass short-circuits the first and second fluid spaces when the actuation piston is not substantially proximate to either the first or second end of the actuation cylinder.

Abstract: Actuators and corresponding methods and systems for controlling such actuators offer efficient, fast, flexible control with large forces. In an exemplary embodiment, an fluid actuator includes a housing having first and second fluid ports, an actuation cylinder in the housing defining a longitudinal axis and having first and second ends in first and second directions, an actuation piston in the cylinder with first and second surfaces moveable along the longitudinal axis, a spring subsystem biasing the actuation piston to a neutral position, a first fluid space defined by the first end of the actuation cylinder and the first surface of the actuation piston, a second fluid space defined by the second end of the actuation cylinder and the second surface of the actuation piston; and a flow bypass that short-circuits the first and second fluid spaces when the actuation piston is not proximate to the second end of the actuation cylinder.

Abstract: Improved actuators and valve control systems, and methods for controlling actuators and/or engine valves, are disclosed. In addition to the inherent capability of timing control, the ability to provide continuous valve lift or stroke control greatly improves engine achieve fuel economy, emission and performance. The power-off state of the actuator is at the minimum stroke, from which an easy start-up can be directly executed. The minimum stroke is also very beneficial to achieve efficient low load operation. Even with continuous lift variation, the present invention is able to keep the spring force neutral or zero point in the center of a stroke, thus maintaining an efficient scheme of energy conversion and recovery through the pendulum action. When in compression braking or other high engine cylinder air pressure working mode, the invention is able to supply necessary force to open the engine valve.

Abstract: Actuators, and corresponding methods and systems for controlling such actuators, provide independent lift and timing control with minimum energy consumption. In an exemplary embodiment, an electromechanical actuator comprises a housing, first and second electromagnets rigidly disposed in the housing and separated from each other by an armature chamber, an armature disposed in the armature chamber and movable between the first and second electromagnets, an armature rod rigidly connected with the armature and operably connected with a load, at least one first actuation spring biasing the armature in a first direction, at least one second actuation spring biasing the armature in a second direction, and one fluid-operated spring controller capable of controlling the position of the first-direction end of the at least one second actuation spring. The spring controller allows the actuation springs at their least compressed state and the engine valve closed when engine power is off.

Abstract: Improved actuators and valve control systems, and methods for controlling actuators and/or engine valves, are disclosed. In addition to the inherent capability of timing control, the ability to provide continuous valve lift or stroke control greatly improves engine achieve fuel economy, emission and performance. The power-off state of the actuator is at the minimum stroke, from which an easy start-up can be directly executed. The minimum stroke is also very beneficial to achieve efficient low load operation. Even with continuous lift variation, the present invention is able to keep the spring force neutral or zero point in the center of a stroke, thus maintaining an efficient scheme of energy conversion and recovery through the pendulum action. When in compression braking or other high engine cylinder air pressure working mode, the invention is able to supply necessary force to open the engine valve.

Abstract: Actuators, and corresponding methods and systems for controlling such actuators, provide independent lift and timing control with minimum energy consumption. In an exemplary embodiment, an actuation cylinder in a housing defines a longitudinal axis and having first and second ends in first and second directions. An actuation piston in the cylinder, with first and second surfaces, is moveable along the longitudinal axis. First and second actuation springs bias the actuation piston in the first and second directions, respectively. A first fluid space is defined by the first end of the actuation cylinder and the first surface of the actuation piston, and a second fluid space is defined by the second end of the actuation cylinder and the second surface of the actuation piston. A fluid bypass short-circuits the first and second fluid spaces when the actuation piston is not substantially proximate to either the first or second end of the actuation cylinder.

Abstract: Improved actuators and valve control systems, and methods for controlling actuators and/or engine valves, are disclosed. In addition to the inherent capability of timing control, the ability to provide continuous valve lift or stroke control greatly improves engine achieve fuel economy, emission and performance. The power-off state of the actuator is at the minimum stroke, from which an easy start-up can be directly executed. The minimum stroke is also very beneficial to achieve efficient low load operation. Even with continuous lift variation, the present invention is able to keep the spring force neutral or zero point in the center of a stroke, thus maintaining an efficient scheme of energy conversion and recovery through the pendulum action. When in compression braking or other high engine cylinder air pressure working mode, the invention is able to supply necessary force to open the engine valve.

Abstract: Improved actuators and valve control systems, and methods for controlling actuators and/or engine valves, are disclosed. In addition to the inherent capability of timing control, the ability to provide continuous valve lift or stroke control greatly improves engine achieve fuel economy, emission and performance. The power-off state of the actuator is at the minimum stroke, from which an easy start-up can be directly executed. The minimum stroke is also very beneficial to achieve efficient low load operation. Even with continuous lift variation, the present invention is able to keep the spring force neutral or zero point in the center of a stroke, thus maintaining an efficient scheme of energy conversion and recovery through the pendulum action. When in compression braking or other high engine cylinder air pressure working mode, the invention is able to supply necessary force to open the engine valve.