Abstract: Three-way valves having reduced leakage and fuel injectors using the same. Three-way spool poppet valves are disclosed having a spool with a poppet valve thereon cooperating with a seat on the valve housing to provide a substantially leak free valve closing in one direction characteristic of a poppet valve while preserving the advantages of a spool valve. Three-way ball valves are also disclosed having substantially leak free valves closing in both directions, but further including reduced short circuit losses due to direct flow from a high pressure source to a low pressure vent during transition of the ball from one position to the opposite position. Fuel injectors with direct needle control using the three-way valves of the present invention are also disclosed.

Abstract: Three-way valves having reduced leakage and fuel injectors using the same. Three-way spool poppet valves are disclosed having a spool with a poppet valve thereon cooperating with a seat on the valve housing to provide a substantially leak free valve closing in one direction characteristic of a poppet valve while preserving the advantages of a spool valve. Three-way ball valves are also disclosed having substantially leak free valves closing in both directions, but further including reduced short circuit losses due to direct flow from a high pressure supply to a low pressure vent during transition of the ball from one position to the opposite position. Fuel injectors with direct needle control using the three-way valves of the present invention are also disclosed.

Abstract: Three-way valves having reduced leakage and fuel injectors using the same. Three-way spool poppet valves are disclosed having a spool with a poppet valve thereon cooperating with a seat on the valve housing to provide a substantially leak free valve closing in one direction characteristic of a poppet valve while preserving the advantages of a spool valve. Three-way ball valves are also disclosed having substantially leak free valves closing in both directions, but further including reduced short circuit losses due to direct flow from a high pressure source to a low pressure vent during transition of the ball from one position to the opposite position. Fuel injectors with direct needle control using the three-way valves of the present invention are also disclosed.

Abstract: Three-way poppet valves having a poppet valve body, first and second poppet valves disposed in a valve guide within the body for motion between first poppet valve open and first poppet valve closed positions, a first poppet valve seat disposed in the poppet valve body so as to have freedom in a plane perpendicular to the poppet valve axis, the first poppet valve, when moving to the closed position, engaging the first poppet valve seat and centering the first poppet valve seat with respect to the first poppet valve, and when in the closed position, holding the first poppet valve seat against the poppet valve body, and a second poppet valve connected with the first poppet valve, the poppet valve body having a second poppet valve seat, the second poppet valve being in the closed position when the first poppet valve is in the open position and being in the open position when the first poppet valve is in the closed position.

Abstract: Hydraulic valve actuation systems and methods to provide multiple lifts for engine valves using fixed or hard stops at each lift. The fixed or hard stops provide a very repeatable selection of engine valve lifts dependent on engine operating conditions. For full valve lift, unidirectional hydraulic dashpots are used to decelerate the engine valve, both as it approaches the full lift fixed stop, and as the engine valve approaches the valve seat from the engine valve full lift position. Various embodiments and methods of operation are disclosed.