Pipe joints or couplings – Safety release
Reexamination Certificate
1997-01-21
2004-04-20
Nicholson, Eric K. (Department: 3679)
Pipe joints or couplings
Safety release
C285S002000, C285S388000, C251S149400
Reexamination Certificate
active
06722701
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to conduit couplings for fluid containing cylinders. More particularly, the invention relates to LP gas conduit couplings that include a fuse for automatic disconnection in the event of fire or potential fire.
BACKGROUND OF THE INVENTION
Traditional LP gas valve connectors have used a P.O.L. nipple surrounded by a left hand nut. Generally, the nut threads into the outlet section of the cylinder valve with a 0.880″ thread at 14 threads/inch.
Many LP gas valve connectors now have included a heat sensitive nut to couple the nipple to the gas cylinder. The nut is designed to fail if the temperature reaches a temperature that could cause or indicate fire. Disconnection of the fluid-carrying conduits triggers an interruption in the fluid flow path. The interruption of the fluid flow path halts the flow of fuel, such as LP gas, to the heat source to prevent or reduce the possibility of fire.
The heat sensitive nut may be exposed to direct sunlight. This exposure to sunlight has caused such nuts to soften unevenly or in some cases fail. Such softening may distort the assembly producing premature decoupling or interruptions in fluid flow. It may also cause misalignment between the nipple and the nut creating problems in coupling and decoupling. Thus, a need existed to prevent direct exposure to sunlight of the heat sensitive material in the coupling.
Other couplings have been designed where only a portion of the nut is made of a heat sensitive material. At the very least, those systems require that the nut be replaced once the system fails. Thus, a need exists to reduce replacement costs for such systems.
SUMMARY OF THE INVENTION
The present invention includes a coupling system comprising a nipple, a check valve, a nut rotatably disposed around the nipple, and a fuse disposed around the nipple between the nut and the fluid entry end of the nipple. The fuse is composed of a heat sensitive material.
The fuse is configured to deform when subject to heat to ensure that the check valve is triggered closing off the flow of fluid. Furthermore, there is no need to replace the nut after failure—only the fuse must be replaced. The present invention reduces and in some case eliminates misalignment between nut and nipple because of its long, direct guiding surface contact between nipple and nut.
REFERENCES:
patent: 4825893 (1989-05-01), Gailey
patent: 4911194 (1990-03-01), Lechner
patent: 5330155 (1994-07-01), Lechner
patent: 5540250 (1996-07-01), Mullins
patent: 5582201 (1996-12-01), Lee et al.
patent: 5979867 (1999-11-01), Ortiz Godinez
Forgamex S.A. DE C.V.
Fulbright & Jaworski LLP
Nicholson Eric K.
LandOfFree
Quick connect coupling having a shielded fuse does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Quick connect coupling having a shielded fuse, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Quick connect coupling having a shielded fuse will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3203540