Induction system for supercharged engine

In an engine including an expansible chamber having a combustion air inlet;

• power control means, a supercharger of the type which compresses air by displacement into a higher pressure region;
• a manifold assembly defining first and second air flow paths connected in parallel, the first path for receiving unboosted air and delivering the unboosted air to the chamber, and the second path for delivering unboosted air to the supercharger inlet and for delivering air from the supercharger outlet to the chamber;
• the improvement comprising:
• a recirculation path defined by the manifold for delivering air from the supercharger outlet back to the supercharger inlet;
• and
• valve means movable between first and second positions for controlling the air flow in said paths, said valve means operative in said first position to allow air flow to the chamber via the first path and to allow air flow in said recirculation path from the supercharger outlet back to the supercharger inlet, and said valve means operative in said second position to allow supercharged air flow to the chamber via the second path and to block air flow in the first and recirculation paths.

In a system adapted to supply combustion air to an inlet of an expansible combustion chamber of an engine having a compressor to boost the pressure of the air;

• the system including a manifold assembly defining first and second air flow paths, the first path having an inlet adapted to receive unboosted air and an outlet adapted to communicate air in the first path with the expansible chamber inlet, the second path having an air inlet and outlet communicating respectively with upstream downstream portions of said first path, the second path inlet and outlet adapted to be interposed by the compressor;
• a first valve disposed in the first path between the second path inlet and outlet and movable between open and closed positions respectively allowing and blocking air flow thereacross;
• the improvement comprising:
• an air recirculation path for communicating compressor discharge air at the second path outlet back to the second path inlet when the first valve is open;
• and
• a second valve interposed between said second path outlet and the downstream portion of the first path, said second valve closed when said first valve is fully open and said second valve open when said first valve is fully closed.

In an engine including an expansible combustion chamber having a combustion air inlet;

• power control means;
• a supercharger to boost the pressure of the air;
• a manifold assembly defining first and second air flow paths, the first path having an unboosted air inlet and an outlet communicating with the chamber inlet, and the second path having an air inlet and outlet communicating respectively with upstream and downstream portions of said first path via the supercharger;
• a first valve disposed in the first path between the second path inlet and outlet and movable between open and closed positions allowing and blocking air flow thereacross;
• the improvement comprising:
• an air recirculation path communicating supercharger discharge air at the second path outlet back to the second path inlet, when the first valve is open;
• and
• a second valve interposed between said second path outlet and said downstream portion of the first path, said second valve closed when said first valve is fully open and said second valve open when said first valve is fully closed.

In a spark ignition engine including an expansible chamber having a combustion air inlet;

• a supercharger to boost the pressure of the air;
• a manifold assembly defining first and second air flow paths for directing unboosted and boosted air to the chamber inlet;
• the first path having an unboosted air inlet and an outlet communicating with the chamber inlet, and the second path having an air inlet and outlet communicating respectively with upstream and downstream portions of said first path via the supercharger;
• a first valve disposed in the first path between the second path inlet and outlet and movable between open and closed positions allowing and blocking air flow thereacross;
• an apparatus for supplying atomized fuel to the air;
• and a power control valve closed to decrease engine power and opened to increase engine power;
• the improvement comprising:
• means for closing the first valve in direct response to opening of the power control valve.

In a spark ignition engine including an expansible combustion chamber having a combustion air inlet;

• an apparatus for supplying atomized fuel to the air;
• a power control valve which closes to reduce power and opens to increase power;
• a positive displacement supercharger mechanically driven by the engine for boosting the pressure of the air;
• a manifold assembly defining first and second air flow paths for directing unboosted and boosted air to the chamber inlet, the first path having an unboosted air inlet and an outlet communicating with the chamber inlet, and the second path having an air inlet and outlet communicating respectively with upstream and downstream portions of said first path via the supercharger;
• a first valve disposed in the first path between the second path inlet and oulet and movable between open and closed positions allowing and blocking air flow thereacross;
• the improvement comprising:
• an air recirculation path for communicating supercharger discharge air at the second path outlet back to the second path inlet;
• and
• a second valve interposed between said second path outlet and the downstream portion of the first path, said second valve closed when said first valve is fully open and said second valve open when said first valve is fully closed.