Induction system for internal combustion engine having multiple inlet valves
AssigneeNissan Motor Co., Ltd.
InventorsSuehiro Urabe, Yoshio Iwasa
Life of this patent
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Abstract
Each combustion chamber of the engine is communicated with (a) first and second induction passages which are dimensioned to produce an optimal ramming effect during high speed and (b) a third passage which provides good ramming during low engine speed operation. The first and second induction passages are provided with flow control valves which can be opened simultaneously or in a step-wise manner as the engine speed moves from a low speed range into a high speed one. The third passage is arranged to merge with the first so that during idling and the like, the flow of air therefrom enters the combustion chamber in a manner which produces a strong swirl and promotes good atomization of the fuel injected into the first passage by a fuel injector.
Claims9
In an internal combustion engine
- means defining a combustion chamber;
- first and second induction ports leading to said combustion chamber;
- first and second inlet valves for controlling fluid communication between said combustion chamber and said first and second induction ports respectively;
- an induction manifold including a collector section and a structure which defines first and second induction conduits which lead from said collector section to said first and second induction ports respectively;
- first and second flow control valves disposed in said first and second conduits respectively, said first and second flow control valves being located upstream of said first and second inlet valves;
- a third flow control valve upstream of said collector, said third valve controlling the amount of air which enters said collector;
- a device for causing said first and second flow control valves to close independently of said third flow control valve and prevent the flow of fluid from said collector section to said combustion chamber during a predetermined first mode of engine operation and for opening said valves when said engine enters a second predetermined mode of engine operation;
- a third induction port, said third induction port being arranged to merge with said first port at an acute angle at a location downstream of said first flow control valve;
- and
- a single third conduit which leads from said collector section to said third port;
- said first, second, and third conduits constituting the entire flow path from said collector section to said induction ports;
- the length and cross sectional area of the flow paths defined between said collector section and said combustion chamber via said first and second induction conduits and first and second induction ports being selected to induce good induction efficiency during said second mode of engine operation and the length and cross sectional area of the flow path defined between said collector section and said combustion chamber via said third conduit and third port selected to induce good induction efficiency during said first mode of engine operation.
Dependencies are inferred from the claim text.