Four-cycle engine
AssigneeYamaha Hatsudoki Kabushiki Kaisha
InventorsJun Taue, Shunzo Fujiwara
Life of this patent
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Abstract
An engine induction system having a check valve upstream of the intake port for precluding reverse flow. A plenum device is communicated with the induction system downstream of the check valve for reducing inertial effects and improving charging efficiency. The plenum device may be the crankcase chamber of the engine. In that case crankcase ventilation may also be controlled and improved. Crankcase supercharging may also be generated. These features may be combined with variable valve timing to further improve engine performance.
Claims27
An internal combustion engine having a combustion chamber, an induction system for delivering a charge to said combustion chamber, and a crankcase chamber, said induction system comprising an intake passage terminating at an intake port communicating with said combustion chamber, control means for sequentially opening and closing said intake port dating a cycle of operation of said engine, a check valve in said intake passage upstream of said control means for permitting flow through said intake passage to said combustion chamber and precluding reverse flow through said intake passage, and means for communicating with said crankcase chamber, said intake passage between said check valve and said control valve means for accommodating continued flow through the portion of said intake passage downstream of said check valve therefrom into said crankcase chamber after said control valve means closes said intake port.
An internal combustion engine having a combustion chamber, a crankcase chamber in which a crankshaft rotates, an induction system for delivering a charge to said combustion chamber, said induction system comprising an intake passage terminating at an intake port communicating with said combustion chamber, intake valve means for sequentially opening and closing said intake port during a cycle of operation of said engine and operated in timed relationship to said crankshaft, a check valve positioned in said intake passage upstream of said intake port for permitting flow through said intake passage to said combustion chamber and for precluding reverse flow through said intake passage, and crankcase ventilation control means comprising control valve means for selectively communicating said crankcase chamber with said induction system upstream or downstream of said check valve.
Dependencies are inferred from the claim text.