Solderless, Field Removable Cap And Seal For Modules
Original Publication Date: 1979-May-01
Included in the Prior Art Database: 2005-Feb-20
A schematic of cap 1 and substrate 2 is shown in the figure. These are in direct physical contact, except for a very thin layer 3 of vacuum grease. This allows slippage while ensuring hermeticity. Silicone greases do not freeze or melt from 40 degrees C to 100 degrees C, and are chemically inactive. Mechanical requirements are that the mating surfaces be both smooth and flat. Spring clip 4 provides enough tension to compress the cushion 5 and force the thin portion 6 to conform to the substrate. The clip 4 also resists the force on the cap 1 due to the inside-outside pressure difference. Because the seal permits some slippage, the cap 1 and substrate 2 can be mismatched thermally. Thus, cap 1 can be made of aluminum or copper for smaller (delta) T's within the module and for better heat dissipation.