Patent ID: 8485154

Claim:
An intake manifold flange for joining a cylinder head and an intake manifold of an internal combustion engine, the cylinder head and the intake manifold changing their relative position to each other due to thermal expansion and contraction, respectively caused by an operation and a stop of an internal combustion engine, the intake manifold flange comprising: a flange body made from a metal; and O-rings formed from an elastic material, wherein the flange body is provided with an opening for inserting a distal end of the intake manifold and bolt insertion holes for fixing the flange body to the cylinder head, the intake manifold being axially movably when inserted into the opening; a plurality of annular grooves, arranged with a spacing along the axial direction of the intake manifold, are provided in an inner circumferential surface of the opening of the flange body, and an outer circumference of at least one of the O-rings is fitted at the inner circumference thereof into each of the plurality of annular grooves; the outer circumference of the intake manifold has an annular portion with which an inner circumference of at least one of the O-rings is brought into an elastic intimate contact at the outer circumference surface thereof; an annular groove is formed in the flange body at the joining surface thereof with the cylinder head, so as to surround the outer circumference of the opening provided in the flange body, and one of the O-rings that is brought into intimate contact with the surface of the cylinder head is fitted into this annular groove; the flange body and the intake manifold are provided with lubricating grease between the inner circumference of the flange body and the outer circumference of the intake manifold, the lubricating grease allowing slippage between the O-rings and the intake manifold; and the flange body allows the axial movement of the intake manifold relative to the flange body by deformation of the O-rings and the slippage between the O-rings and the intake manifold due to the lubricating grease when the cylinder head is fixed with, a bolt to the flange body.