초록 ▼

A heat shield for an internal combustion engine used in a boat, or other application where engine compartment heat is unwanted, has a water cooled body positioned around, but spaced apart from, the exterior surfaces of the exhaust manifold of the engine. The concavity of the heat shield body fits th

A heat shield for an internal combustion engine used in a boat, or other application where engine compartment heat is unwanted, has a water cooled body positioned around, but spaced apart from, the exterior surfaces of the exhaust manifold of the engine. The concavity of the heat shield body fits the manifold and engine closely, to intercept and carry away radiant and convective heat. The shield is held in place by means of a boss which is captured between the exhaust manifold and the exhaust pipe of the engine. The shield enables industrial engines to be adapted to marine use without re-certification to meet environmental regulations.

대표청구항 ▼

I claim: 1. An internal combustion engine system comprising: an engine block cooled by liquid coolant; an exhaust manifold attached to the engine block, the manifold having an exhaust port fitting spaced apart from the engine block; an exhaust pipe, having an end for connecting to said exhaust port

I claim: 1. An internal combustion engine system comprising: an engine block cooled by liquid coolant; an exhaust manifold attached to the engine block, the manifold having an exhaust port fitting spaced apart from the engine block; an exhaust pipe, having an end for connecting to said exhaust port fitting, for carrying away engine exhaust gases which flow from the engine block and through said manifold; and, a heat shield having a concave portion, at least partially enveloping the manifold, the interior of said concave portion spaced apart from the manifold by an air gap, for receiving heat from the manifold; cooling passageways, upon or within the heat shield, for carrying away heat received by said concave portion; and, means for mounting the heat shield with respect to the exhaust manifold without any heat-transfer conductive contact with the manifold upstream of said exhaust port fitting. 2. The system of claim 1 where said means for mounting comprises: a boss having a gas passageway, connected to and captured between said exhaust port fitting and the end of the exhaust pipe, wherein the heat shield is thereby mounted with said concave portion cantilevered from the boss toward the engine; said passageway enabling gas flow from the exhaust manifold to the exhaust pipe. 3. The system of claim 1 wherein the heat shield has a double wall construction, wherein the spaces between the double walls provide said coolant passageways. 4. The system of claim 1 further comprising: means for flowing said liquid engine coolant through said coolant passage ways. 5. The system of claim 1 wherein the heat shield further comprises: a reservoir for liquid coolant. 6. The system of claim 1 wherein said concave portion has only a vertical planar opening adjacent the engine block. 7. The system of claim 1 wherein the heat shield concave portion has portions which are free of cooling passageways. 8. The apparatus of claim 1 wherein said engine is an industrial engine environmentally certified for land use with an uncooled manifold, and wherein apparatus is mounted within the hull of a boat. 9. A heat shield for use in combination with an exhaust manifold of an internal combustion engine, wherein the manifold has an exhaust port fitting adapted for attachment to the end of an exhaust pipe, which heat shield comprises: a body having a concave portion with coolant passageways, the interior of the portion shaped for at least partially enveloping said manifold while maintaining an ambient air gap spacing there between, for receiving radiant and convective heat from the manifold during engine operation; ports on said body, for flowing coolant to and from said passageways; a boss attached to the body, for mounting the heat shield at the exhaust port fitting of the manifold, the boss having a first face for mating with said fitting; an opposing side second face for receiving the end of said exhaust pipe; and, an exhaust gas passageway connecting said faces; wherein the boss is attached to the body at one end of said concave portion, so said concave portion cantilevers from the boss location so that the concave portion is adapted to at least partially envelope a manifold when the boss is attached to said exhaust manifold fitting. 10. The heat shield of claim 9 wherein the body concave portion is a cavity having only one planar opening, so that when mounted on an exhaust manifold, the heat shield opening is adapted to lie in proximity to an engine to which the manifold is attached. 11. The heat shield of claim 9 wherein the body has double walls with spaces therebetween, wherein said spaces comprise said coolant passageways. 12. The shield of claim 9 wherein said body further comprises a reservoir for holding liquid coolant, the reservoir connected to said coolant passageways. 13. The shield of claim 9 wherein part of said concave portion lacks coolant passageways. 14. A method of adapting a liquid cooled land-use industrial engine for use in a boat, wherein the engine has an uncooled exhaust manifold and is environmentally certified by regulatory authorities for land use, to reduce heating of the interior of the boat which contains the engine within without substantially cooling the manifold and thereby changing the gas path conditions within the manifold during engine operation, which comprises: surrounding at least a substantial part of the exterior of the exhaust manifold with the concavity of a heat shield, wherein the interior of the concavity is spaced apart from the manifold by an air gap; flowing coolant through coolant passageways of the heat shield, to thereby carry away convective and radiant heat received from the manifold through the air gap during engine operation; and, avoiding cooling or heating of the manifold upstream of the exhaust exit port by contact with the heat shield. 15. The method of claim 14 wherein liquid coolant used to cool the engine is flowed through said heat shield coolant passageways. 16. The method of claim 14 further comprising: surrounding all sides of the manifold with said spaced-apart concavity except where the manifold is connected to the engine and where the manifold is connected to an exhaust pipe.