MANIFOLD SYSTEM FOR AN INTERNAL COMBUSTION ENGINE

1473153 Heating I C engine charge; manifolds HONDA GIKEN KOGYO K K 29 July 1974 [30 July 1973 5 Nov 1973] 33454/74 Heading F1 Intake and exhaust apparatus for an I.C. piston engine of the type wherein the or each cylinder has a main combustion chamber and a precombustion chamber communicating with the main combustion chamber via a flame passage, the apparatus comprising intake means including a main intake chamber and at least one main intake passageway extending from the main intake chamber for delivering an air/fuel mixture to the or each main combustion chamber, the intake means also including an auxiliary intake chamber and at least one auxiliary intake passageway extending from the auxiliary intake chamber for delivering a richer air/fuel mixture to the or each pre-combustion chamber, exhaust means comprising a thin wall liner enveloped by and spaced within a thicker wall outer cover, the liner forming at least one passageway for collecting exhaust gases from the or each main combustion chamber and also forming an exhaust chamber connected to the exhaust passageway(s), the exhaust means having an opening and a heat conductive member forming a part of the intake means and in communication with said opening to transfer heat of the exhaust gases to the intake mixtures in the main and auxiliary intake chambers, the heat conductive member having a first portion adjacent the auxiliary intake chamber and a second portion adjacent the main intake chamber, the first portion having an effective heat conductive area of from “ to 2/ 3 that of the second portion. The combined intake and exhaust system is shown, Fig. 2, in an engine having pre-combustion chamber 1 communicating with each main combustion chamber 2 through a restricted flow passage 6. A main carburetter assembly supplies a lean air-fuel mixture to the main combustion chambers 2 through the manifold 17 and the auxiliary carburetter supplies a rich air-fuel mixture to the auxiliary combustion chambers 1 through the manifold 16. A main fuel intake chamber 20 and an auxiliary fuel intake chamber 32 are formed adjacent a riser member 84 covering an opening in the housing 42 of the exhaust pipe manifold 15. The housing 42 encloses a liner 44 formed of thin heat resistant material such as stainless steel. The liner 44 extends from the engine head 3 to the exhaust pipe system 56 and comprises an exhaust chamber 62 having-inlets 65 from the combustion chambers and a discharge pipe 66 leading to the exhaust pi