Engine cylinder head gasket

Claim 2

A composite cylinder head gasket for an internal combustion engine, said gasket comprising a sheet metal body having a plurality of spaced cylinder openings adapted to register with the engine cylinders and at least one additional opening adapted to register with liquid containing cavities of the engine cylinder block and head, a layer of sheet graphite covering each of the opposite surfaces of said metal body, said graphite having a density less than its maximum and being compressible to approximately its maximum density, said composite gasket having first annular sealing portions surrounding said cylinder openings with edges of said graphite exposed thereto and a second sealing portion surrounding said at least one additional opening with edges of said graphite exposed thereto, said first sealing portions being substantially thicker than the remainder of said gasket but compressible to a thickness substantially less than the uncompressed thickness of said second sealing portion, whereby said gasket may be compressed between opposing flat surfaces to a thickness at which the graphite of said first sealing portions exposed to said cylinder openings approaches its maximum density while the graphite of said second sealing portion is compressed to a substantially smaller extent.

Claim 3

A composite cylinder head gasket for installation between flat opposing surfaces of the cylinder head and block of an internal combustion engine to seal the joint against leakage from the engine cylinders and other fluid-containing chambers opening through said flat surfaces, said gasket comprising a generally flat sheet metal body with a coating of graphite sealing material covering each of the opposite surfaces of said sheet metal body, said graphite material having a density not greater than ninety percent (90%) of its fully compressed density, said gasket having a plurality of spaced cylinder openings adapted to register with the engine cylinders and a plurality of additional openings adapted to register with at least one other fluid-containing cavity of the engine, said gasket being of substantially uniform thickness except for narrow annular portions adjacent and surrounding said cylinder openings wherein edges of said graphite are exposed to said cylinder openings, said annular portions being thicker than the remainder of said gasket by substantially less than the amount of compression required to fully compress said annular portions of the gasket.

Claim 4

A composite cylinder head gasket for installation between flat opposing surfaces of the cylinder head and block of an internal combustion engine to seal the joint against leakage from the engine cylinders and other fluid-containing chambers opening through said flat surfaces, said gasket comprising a generally flat sheet metal body with a coating of graphite sealing material covering each of the opposite surfaces of said sheet metal body, said graphite material having a density not greater than ninety percent (90%) of its fully compressed density, said gasket having a plurality of spaced cylinder openings adapted to register with the engine cylinders and a plurality of additional openings adapted to register with at least one other fluid-containing cavity of the engine, said gasket being of substantially uniform thickness except for narrow annular portions adjacent and surrounding said cylinder openings wherein edges of said graphite are exposed to said cylinder openings, said annular portions being thicker than the remainder of said gasket by substantially less than the amount of compression required to fully compress said annular portions of the gasket.

Claim 5

The gasket of claim 2 wherein said coating has a substantially constant thickness along each side of said metal body and said metal body is folded over adjacent said spaced cylinder openings whereby the increased thickness of said annular portions is provided.

Claim 6

The gasket of claim 2 wherein said metal body is of substantially constant thickness and said coating is applied with greater thickness on at least one side of said body adjacent said spaced cylinder openings.

Claim 7

The gasket of claim 2 wherein the increased thickness adjacent said Spaced cylinder openings is provided by additional ring members applied between said metal body and said coating on at least one side surrounding said cylinder openings.

Claim 8

The gasket of claim 2 wherein said metal body includes a plurality of locking tines bent outwardly from the main portion of said body and projecting into said coating for improved retention thereof.

Claim 9

The combination in an internal combustion engine of a cylinder block having a plurality of spaced cylinders opening through a wall thereof and including interior oil and coolant passages also opening through said wall, a cylinder head mounted on said wall and closing said cylinders, said cylinder head including oil and coolant passages connecting with said block passages through said wall, and a cylinder head gasket compressed between said cylinder block and said cylinder head and sealing the joint therebetween against leakage of fluids from said cylinders and said oil and coolant passages, said gasket being formed at least in part from sheet graphite of less than maximum density before installation and having edges thereof directly exposed to said cylinders, the opposing portions of said cylinder head and said block being related to the construction of said gasket such that upon installation and securing of said gasket in position with a predetermined clamping load, said graphite is differentially compressed, such that in said combination, annular portions of said graphite adjacent said cylinders and exposed to gas pressures and temperatures therein are compressed to substantially their maximum density while the remaining portions of said graphite are compressed a lesser amount but sufficient to provide a seal for said oil and water passages.

Claim 10

The combination in an internal combustion engine of a cylinder block having a plurality of spaced cylinders opening through a wall thereof and including interior oil and coolant passages also opening through said wall, a cylinder head mounted on said wall and closing said cylinders, said cylinder head including oil and coolant passages connecting with said block passages through said wall, and a cylinder head gasket compressed between said cylinder block and said cylinder head and sealing the joint therebetween against leakage of fluids from said cylinders and said oil and coolant passages, said gasket being formed at least in part from sheet graphite of less than maximum density before installation and having edges thereof directly exposed to said cylinders, the opposing portions of said cylinder head and said block being related to the construction of said gasket such that upon installation and securing of said gasket in position with a predetermined clamping load, said graphite is differentially compressed, such that in said combination, annular portions of said graphite adjacent said cylinders and exposed to gas pressures and temperatures therein are compressed to substantially their maximum density while the remaining portions of said graphite are compressed a lesser amount but sufficient to provide a seal for said oil and water passages.