Abstract: For controlling motion of a movable part, a device comprises a first chamber and a second chamber in fluid communication with each other via a variable orifice that is responsive to pressure within the first chamber. Movement of the movable part is thereby at least partially controlled by flow of a fluid from the first chamber to the second chamber via the variable orifice. An increase in pressure in the first chamber may cause an increase in orifice area, whereas a decrease in pressure may cause a decrease in the orifice area. Pressure-dependent elements that change geometries and/or the pressure-based opening/closing of one or more bypass channels may be used for this purpose. Where bypass channels are used, a valve may be opened/closed based on an operating parameter of a system in which the movable part is a component. Such a system may comprise an internal combustion engine.

Abstract: Devices and related methods are disclosed that generally involve the selective deactivation of one or more engine valves. In one embodiment, a split-cycle internal combustion engine is provided in which a high-speed trigger valve is used to fill and drain a hydraulic tappet that forms part of a lost-motion system of an engine valve. A spool valve can be used to selectively disconnect the tappet from the trigger valve, thereby deactivating the associated engine valve (i.e., preventing the engine valve from opening). The devices and methods disclosed herein also have application in conventional internal combustion engines and can be used with inwardly-opening and/or outwardly-opening valves.

Abstract: For controlling motion of a movable part, a device comprises a first chamber and a second chamber in fluid communication with each other via a variable orifice that is responsive to pressure within the first chamber. Movement of the movable part is thereby at least partially controlled by flow of a fluid from the first chamber to the second chamber via the variable orifice. An increase in pressure in the first chamber may cause an increase in orifice area, whereas a decrease in pressure may cause a decrease in the orifice area. Pressure-dependent elements that change geometries and/or the pressure-based opening/closing of one or more bypass channels may be used for this purpose. Where bypass channels are used, a valve may be opened/closed based on an operating parameter of a system in which the movable part is a component. Such a system may comprise an internal combustion engine.

Abstract: Devices and related methods are disclosed that generally involve the selective deactivation of one or more engine valves. In one embodiment, a split-cycle internal combustion engine is provided in which a high-speed trigger valve is used to fill and drain a hydraulic tappet that forms part of a lost-motion system of an engine valve. A spool valve can be used to selectively disconnect the tappet from the trigger valve, thereby deactivating the associated engine valve (i.e., preventing the engine valve from opening). The devices and methods disclosed herein also have application in conventional internal combustion engines and can be used with inwardly-opening and/or outwardly-opening valves.

Abstract: Devices and related methods are disclosed that generally involve the selective deactivation of one or more engine valves. In one embodiment, a split-cycle internal combustion engine is provided in which a high-speed trigger valve is used to fill and drain a hydraulic tappet that forms part of a lost-motion system of an engine valve. A spool valve can be used to selectively disconnect the tappet from the trigger valve, thereby deactivating the associated engine valve (i.e., preventing the engine valve from opening). The devices and methods disclosed herein also have application in conventional internal combustion engines and can be used with inwardly-opening and/or outwardly-opening valves.

Abstract: Devices and related methods are disclosed that generally involve the selective deactivation of one or more engine valves. In one embodiment, a split-cycle internal combustion engine is provided in which a high-speed trigger valve is used to fill and drain a hydraulic tappet that forms part of a lost-motion system of an engine valve. A spool valve can be used to selectively disconnect the tappet from the trigger valve, thereby deactivating the associated engine valve (i.e., preventing the engine valve from opening). The devices and methods disclosed herein also have application in conventional internal combustion engines and can be used with inwardly-opening and/or outwardly-opening valves.

Abstract: A system and method for actuating one or more engine valves is provided. In particular, systems and methods for providing variable valve actuation to improve engine performance are provided. Embodiments of the present invention may be used in conjunction with positive power, engine braking, and/or exhaust gas recirculation operation of an internal combustion engine. In one embodiment, the system comprises: a valve train element; a housing disposed intermediate the valve train element and the engine valve; an outer piston slidably disposed in a bore formed in the housing, the outer piston having a cavity formed therein; an inner piston slidably disposed in the outer piston cavity; and a valve in communication with the outer piston cavity, the valve having more than one position, wherein the position of the valve determines the timing of the engine valve event.