Quick-heat engine intake manifold

Claim 2

An internal combustion engine intake manifold comprising a hollow main body portion having spaced upper and lower walls defining a plenum with a plurality of runners extending therefrom each to one of the engine cylinders, the upper wall having a carburetor air/fuel mixture inlet, first means defining an exhaust gas chamber between the inlet and plenum, a thin sheet metal high heat transfer tube connecting the inlet to the plenum through the chamber in heat transfer relationship to simultaneously conduct air/fuel mixture to the plenum while it is being heated by the exhaust gases surrounding the tube, and other means passing exhaust gases beneath a portion of the lower wall beneath the tube for transferring exhaust gas heat to any liquid fuel in contact therewith, the portion comprising a second thin sheet metal high heat transfer member against which liquid fuel splashes for evaporation of the same.

Claim 3

An intake manifold as in claim 1, the lower wall portion comprising a plate corrugated to increase the effective heat transfer surface area.

Claim 4

An intake manifold as in claim 1, the other means comprising a passage in the intake manifold containing engine exhaust gases and passing through the manifold to opposite sides of the manifold, the lower wall containing an outlet and inlet respectively on opposite sides of the portion for passage of exhaust gases out of the manifold and along and beneath the lower wall in heat transfer relationship and back into the manifold.

Claim 5

An intake manifold as in claim 3, including exhaust gas guide means located adjacent to the inlet and outlet for guiding the gases along the lower wall.

Claim 6

An intake manifold for an internal combustion engine comprising a hollow main body portion having spaced upper and lower walls defining a plenum and a plurality of air/fuel mixture conveying runners extending from opposite sides of a central portion of the plenum each to a separate cylinder of the engine, an air/fuel mixture inlet in the upper wall, a thin sheet metal high heat transfer tube connecting the inlet to the central portion for passage of the air/fuel mixture therebetween, the lower wall directly beneath the central portion and tube consisting of a thin high heat transfer sheet metal plate against which air/fuel mixture is splashed upon discharge from the tube, and dual hot exhaust gas passage means to flow hot exhaust gases in a dual path simultaneously around the tube and beneath the plate in a heat transfer relationship for evaporation of liquid fuel passing through the tube and splashed against the plate.

Claim 7

An intake manifold for an internal combustion engine comprising a hollow main body portion having spaced upper and lower walls defining a plenum and a plurality of air/fuel mixture conveying runners extending from opposite sides of a central portion of the plenum each to a separate cylinder of the engine, an air/fuel mixture inlet in the upper wall, a thin sheet metal high heat transfer tube connecting the inlet to the central portion for passage of the air/fuel mixture therebetween, the lower wall directly beneath the central portion and tube consisting of a thin high heat transfer sheet metal plate against which air/fuel mixture is splashed upon discharge from the tube, and dual hot exhaust gas passage means to flow hot exhaust gases in a dual path simultaneously around the tube and beneath the plate in a heat transfer relationship for evaporation of liquid fuel passing through the tube and splashed against the plate.

Claim 8

An intake manifold as in claim 5, the passage means including an exhaust gas crossover passage extending from one side of the manifold to the other in a direction essentially at right angles to the direction of flow of air/fuel mixture to the runners, the crossover passage having a first branch passing between the inlet and central portion and spacing the two for surrounding the tube with hot exhaust gases, and a second passage passing out of the lower wall of the manifold on one side of the plate and along the plate in heat transfer relationship and back into the manifold on the opposite side of the plate.