|
SeaMagine Hydrospace Corproation has a patent that includes a double sealed hatch. In there configuration, they have one seal that seals better near the surface, (likely using a slightly larger and softer O-ring or lipped seal) to make a very good seal. "The chambers in the craft can be sealed using a dual or multi-seal system. In the sealing system, annular seals for operation at varying pressure are provided. It is preferred the outermost seal be the lowest pressure seal, although other arrangements may be provided." http://www.google.com/patents?vid=USPAT6321676 http://www.youtube.com/watch?v=8spX4pRWQyE Regards,
Brent Hartwig |