Selectively conductive EMI gaskets
A fabric over foam electromagnetic interference gasket has a body of indefinite length, and includes a layer of dielectric material thereon. The gasket may be compressed between two substrates and provide electrical conductivity in one axis and EMI shielding and nonconductivity in a perpendicular axis.
1. An electromagnetic interference gasket comprising a body of indefinite length and including:
a core surrounded by an electrically-conductive layer, where the electrically-conductive layer is adhered to the core; and
a nonconductive layer adhered to the electrically-conductive layer;
wherein:
the nonconductive layer surrounds the electrically-conductive layer, the nonconductive layer comprising two series of apertures, each series of apertures comprising a plurality of openings in the nonconductive layer that expose portions of the electrically-conductive layer; and
the two series of apertures run the length of the gasket and are on opposite sides of the gasket.
2. The gasket of claim 1 , wherein:
the core is a foam core; and
the electrically-conductive layer is metallized fabric.
3. The gasket of claim 2 , wherein:
the electrically-conductive layer comprises fabric coated with nickel and/or copper;
the resilient core member comprises polyurethane foam, and further comprising an adhesive disposed between the fabric and the foam; and
the nonconductive layer comprises plastic film.
4. The gasket of claim 1 , wherein:
the gasket is at least partially electrically conductive in one direction perpendicular to the length of the gasket;
the gasket is nonconductive in a second direction perpendicular to both the one direction and the length of the gasket; and
the at least partial electrical conductivity occurs through the apertures.
5. The gasket of claim 1 , wherein the gasket is deflectable between a first substrate and a second substrate, where the gasket provides electrical conductivity between the substrates.
6. The gasket of claim 1 , wherein:
the electrically-conductive layer comprises fabric coated with nickel and/or copper; and
the resilient core member comprises polyurethane foam.
7. The gasket of claim 1 , wherein the nonconductive layer comprises plastic film.
8. The gasket of claim 7 , wherein the plastic film is polyethylene film.
9. A method of manufacturing an electromagnetic interference gasket having a body of indefinite length, the method comprising:
surrounding a foam core of indefinite length with an electrically-conductive layer and adhering the electrically-conductive layer to the core; and
adhering a nonconductive layer to the electrically-conductive layer;
wherein the nonconductive layer comprises two series of apertures, each series of apertures comprising a plurality of openings in the nonconductive layer that expose portions of the electrically-conductive layer upon adhering the nonconductive layer to the electrically-conductive layer.
10. The method of claim 9 , wherein:
the electrically-conductive layer comprises fabric coated with nickel and/or copper;
the resilient core member comprises polyurethane foam; and
the nonconductive layer comprises plastic film.
11. The method of claim 9 , wherein:
the electrically-conductive layer comprises fabric coated with nickel and/or copper; and
the resilient core member comprises polyurethane foam.
12. The method of claim 9 , wherein the nonconductive layer comprises plastic film.