Safety valve

In a combination safety and service valve for a high pressure tank having a valve body including a sealing portion and to thereby be positioned non-externally of the tank, an external portion positioned externally of the tank, an inlet port in said sealing portion, an outlet port in said external portion, a flow passage extending from said inlet port to said outlet port through said sealing and external portions, and an actuatable valve member connected to said external portion for opening and closing said flow passage, the improvement comprising:

• (a) a ball chamber being defined in said flow passage and between said inlet port and said external portion, said ball chamber having an inlet end and an outlet end, said outlet end having a contoured surface positioned within the tank opening between an inlet and an outlet of the tank opening,
• (b) a ball loosely received by said ball chamber and adapted to sealingly engage said contoured surface to thereby close said flow passage, said ball being of such size that when the fluid pressure at said chamber inlet end is higher than the fluid pressure at said ball chamber outlet end, about one-half of said ball is biased toward a condition at which said ball sealingly engages said contoured surface chamber outlet end and substantially all of said ball being disposed within the tank opening between said inlet and said outlet of the tank opening, and
• (c) stop means associated with said valve member for preventing said ball from engaging said contoured surface in all open positions of said valve member until said external portion is severed from said sealing portion.

In combination,

• a high pressure tank defining an opening through which said tank is filled and emptied, and
• a safety and service valve including
• (a) a body having a sealing portion positioned within said tank opening and an external portion positioned externally of the tank, said sealing portion defining an inlet port, said external portion defining an outlet port, said body defining a flow passage extending between said inlet and said outlet ports so that a portion of said flow passage is provided by said sealing portion and another portion of said flow passage is provided by said external portion of said body, said portion of said flow passage provided by said sealing portion including a ball chamber, said ball chamber having an inlet end and an outlet end, said outlet end having a contoured surface positioned within said tank opening between an inlet and an outlet of the tank opening;
• (b) a spherical ball being loosely received by said ball chamber and adapted to engage said contoured surface to thereby close said flow passage, said ball being of such size that when the fluid pressure at said ball chamber inlet end is higher than the fluid pressure at said ball chamber outlet end, about one-half of said ball is biased into engagement with said contoured surface of said ball chamber and substantially all of said ball being disposed within the tank opening between said inlet and said outlet of the tank opening;
• (c) an actuatable valve member connected to said external portion of said body for opening and closing said flow passage;
• and
• (d) stop means associated with said valve member for preventing said ball from engaging said contoured surface in all open positions of said valve member until said external portion of said body is severed from said sealing portion.