Patent ID: 6553910
Filing Date: 2003-04-29
Classification: F42B

Abstract:
A combination filter-seal assembly of a monolithic combination electrical low-pass radio frequency absorbent filter and mechanical gas-tight seal apparatus,said filter-seal assembly comprising an electrically conductive metallic casing having a passageway therethrough and an interior wall, at least one metallic electrode extending through said passageway and not contacting said casing, and a solid plug means of ceramic material for attenuating high frequency electrical signals and for blocking the passage of gas through the passageway, said attenuating and blocking means including a solid electromagnetically lossy ceramic substantially gas-impermeable plug fused to the interior wall of said casing passageway and said electromagnetically lossy substantially gas-impermeable plug being fused to said electrode so as to embed said electrode within said plug and completely span the remaining free cross section of said passageway, including a mechanical and chemically bonded gas-tight fusion joint between the plug and the metallic casing; and a mechanically and chemically bonded gas-tight fusion joint between the plug and the electrodes; thereby forming a gas-tight electromagnetically lossy seal said plug being electromagnetically lossy and gas-impermeable.