Multi-layered gasket

摘要

A gasket having a first upper layer, a second lower layer and a spacer layer is provided. The first upper layer has a bead located between two lands. The second lower layer also has a bead located between two lands. The spacer layer has an embossment located between two lands. A coating may be located within the embossment. The beads are located in an axial relationship with respect to the embossment.

主权项

1. A gasket, comprising:
a first metallic layer having at least two adjacent combustion openings therein, wherein each opening is circumscribed by a combustion opening edge of said first layer, a first land extends radially from said edge, a single first active bead extends radially from said first land, said single first active bead comprising a first ramp, a first planar portion and a second ramp, and a second land extends radially from said first land, wherein said first land, said first active bead and said second land are unitary, and wherein there are no other beads in the first metallic layer; a second metallic layer having at least two adjacent combustion openings therein, wherein each opening is circumscribed by a combustion opening edge of said second layer, a first land extends radially from said edge, a single first active bead extends radially from said first land, said single first active bead comprising a first ramp, a first planar portion and a second ramp, and a second land extends radially from said first land, wherein said first land, said first active bead and said second land are unitary, and wherein there are no other beads in the second metallic layer; and a spacer layer located between said first and second layers and having at least two adjacent combustion openings therein, wherein each opening is circumscribed by a combustion opening edge of said spacer layer, a first land extends radially from said edge, an embossment extends radially from said first land and a second land extends radially from said embossment, said embossment defined by a first ramp, a planar portion and a second ramp, said spacer layer embossment extends beyond both said first metallic layer first active bead and said second metallic layer first active bead; a channel in said spacer layer embossment extends radially outboard of both said first layer first active bead and said second layer first active bead; and a coating selectively covering only said channel between said combustion openings; wherein, at a time when compression is applied between a cylinder head and a cylinder block, only said single first metallic layer first active bead and said two lands of said first metallic layer are in full contact with a top of said spacer layer and said single second, metallic layer first active bead is in full contact with said coating.