Pressurized vessel having closure safety means

Claim 1

A vessel including a body having an end opening and provided with an internal chamber adapted to contain pressurized gas, a closure spanning said end opening, means on said closure and body providing a removable gas-tight assembly of said closure to said body, said closure having an outer face and an opposite inner face juxtaposed said chamber, said closure provided with an axial gas passage therethrough, said outer face including tool-receiving means adapted to be engaged for disassembly of said closure from said body, a charging valve/cover plate unit having attachment means removably engaging said closure gas passage, said unit including a central gas charging valve and an affixed radially extending planar cover plate, said valve provided with a body having a planar inner face with said attachment means projecting therefrom, said cover plate including an inner surface adapted to overlie said closure tool-receiving means, means captively affixing said cover plate to said valve body with said cover plate inner surface substantially coplanar with said valve inner face, said attachment means comprising an externally threaded stem insertable within said closure gas passage, and means on said valve maintaining a gas-tight seal between said valve and closure when said stem is fully inserted within said gas passage with said valve inner face and cover plate inner surface juxtaposed said closure outer face whereby, removal of said unit from said closure initially relieves said gas-tight seal maintaining means to progressively release pressurized gas from said chamber through said passage to the atmosphere and subsequent total removal of said unit exposes said tool-receiving means to allow safe removal of said closure from said body.