Abstract: A gasket for use in an internal combustion engine is disclosed which includes a sealing element formed by an extrusion and ironing process in combination with a folding operation. The gasket has a plate that includes a body portion, a flange portion and an aperture. The thickness of the flange portion is reduced to less than that of the body portion by the extrusion and ironing process. The flange portion is then folded back onto a surface of the plate in facing relation to form a stopper seal to act as a primary seal. Optional embossments may then be formed radially and outwardly of the stopper seal so as to form a secondary seal.

Abstract: An improved three layer metal gasket is disclosed incorporating both primary and secondary combustion seals for increased combustion seal area durability. The gasket has three plates, a first plate, a second plate, and a third plate. The first and third plates have opposed sealing beads that form the secondary combustion seal. The first and second plates cooperate to position the primary combustion seal and the secondary combustion seal along a central axis such that in operation the opposed sealing beads compress equally, thereby further improving the durability of the combustion area of the gasket. The gasket may further include a fluid seal. Specialized coatings may be used to enhance the sealability of both primary and secondary combustion seals and the fluid seal.

Abstract: A metallic gasket for use in an internal combustion engine has seals around the gasket openings which are formed by a two-step coining operation plus a folding operation. The gasket has a base plate including a folding portion located between an edge of an opening and a fold line. A channel and a reduced thickness portion are formed in the folding portion by a first coining operation. The channel is spaced from the edge of the opening and spaced from the fold line. Next the folding portion is folded back onto the base plate of the gasket. Finally, a second coining operation takes place to flatten the folded seal to a final thickness and produces material flow between the base plate and the folding portion.

Abstract: A cylinder head gasket for an internal combustion engine includes a substantially flat center plate and first and second spring plates disposed on opposite sides of the center plate. The center plate has an opening therein. Both the first and second spring plates have openings therein aligned with and smaller than the opening of the center plate. The first and second spring plates thereby define wire ring retention portions of the spring plates extending radially inwardly from the edge of the center plate opening. A wire ring having a wire diameter greater than a thickness of the center plate is disposed between the ring retention portions of the spring plates. The spring plates have a substantially wave-like concentric embossment encircling the opening in each and radially proximate thereto. Clamping the gasket between two sealing surfaces forms a primary combustion seal at the wire ring, and forms a secondary combustion seal beyond the ring at the embossments.