Stretchable oil seal and method of installation
AssigneeFederal-Mogul Corporation
InventorsStephen E. Nash, Gerald P. Pichler
Life of this patent
Estimating the term…
Abstract
A fluid seal made of elastomeric material for use between an external stationary member and a rotating internal member avoids use of a customary pressed steel case. The seal may be stretched over an external flange on a rotatable shaft and recover from the elongation to the designed dimension at which the seal is to operate within the external stationary member. A specially formulated elastomeric composition accommodates elongation during stretching in excess of 300%.
Claims8
In combination, a stretchable shaft seal stretched over a crankshaft and sealing fluid between said crankshaft and a split housing, said crankshaft having a predetermined diameter and comprising a flange having a diameter substantially greater than said predetermined diameter, said housing comprising a first housing member and a second housing member, said first and second housing members defining a split bore therebetween and clamping said soil therein;
- said seal comprising an elastomeric seal body having a continuous annular form and providing with an integrally molded seal lip, said seal body and said seal lip each comprising an elastomeric material which accommodates elongation over said flanged crankshaft of at least 100% of its original non-stretched length and recovers to its originally molded dimension and forms a continuous positive elastic seal around said flanged crankshaft after undergoing said elongation and wherein leak paths through said seal body are eliminated by said continuous annular form;
- said seal body having an external circumferential outer surface portion compressed within said split bore and forming a continuous non-rotating annular static seal against said split bore;
- and
- said seal lip projecting from said seal body and forming said positive elastic seal as a continuous dynamic elastic seal around seal predetermined diameter of said crankshaft after being stretched over said flange.
In combination, an engine crankshaft having a cylindrical sealing surface and an outwardly radiating flange for attaching the crankshaft to a flywheel;
- a split housing comprising a first housing member defining a first semi-circular concave seal mount surface, and a second housing member defining a second semi-circular concave seal mount surface facing the first concave surface, and means releasably attaching the two split housing members together;
- an elastomeric seal body having a continuous annular form and having a seal lip integrally formed with said seal body of an elastomeric material which accommodates elongation of at least 100% of its original non-stretched length and resiliently recovers to its originally molded dimensions to form a positive dynamic elastic seal around said shaft and wherein leak paths through said seal body are eliminated by said continuous annular form;
- said seal body having an outer circumferential static seal surface, and an inner circumferential dynamic elastic seal surface along said seal lip;
- said seal body being seated in a space circumscribed by said split housing so that said outer circumferential seal surface is compressively engaged by said concave seal mount surfaces on said first and second housing members;
- said crankshaft extending through said seal body, so that the inner circumferential seal surface of said seal body has a dynamic elastic sealing engagement with said cylindrical shaft sealing surface;
- and
- said flange on said crankshaft having a diameter that is substantially larger than the diameter of said crankshaft sealing surface, said crankshaft being constructed so that said seal body is required to be physically stretched over the crankshaft flange in order to install said seal body on said crankshaft sealing surface.
Dependencies are inferred from the claim text.