Heating of intake mixture for auxiliary chamber of internal combustion engine

Claim 1

In a multi-cylinder internal combustion engine in which each cylinder has a main combustion chamber and an auxiliary combustion chamber connected by a torch nozzle, and having a first passage for supplying a rich mixture to the auxiliary chamber and a second passage for conveying hot exhaust gases from the main combustion chamber, the improvement comprising, in combination: a plurality of thin wall intake pipes each connected to one of the first passages, respectively, a plurality of thin wall exhaust pipes each connected to one of the second passages, respectively, pairs of intake and exhaust pipes being curved and contiguous, a thick wall housing having portions enclosing each pair of said pipes, each of said intake pipes being integrally connected to a common auxiliary riser enclosed within said housing, and each of said exhaust pipes being integrally connected to a common exhaust chamber enclosed within said housing, the exhaust chamber having an exit pipe projecting through said housing, said housing having a flange provided with a central opening, and a riser on the flange over the central opening communicating with said intake pipes and said exhaust pipes.