초록 ▼

A flapper-type gas valve automatically closable by accelerations characteristic of earthquakes. The arm is held up in the "valve open" position by a magnet attracting a soft ferromagnetic armature. The armature can be displaced to release the flapper to close the valve, either by seismic acceleratio

A flapper-type gas valve automatically closable by accelerations characteristic of earthquakes. The arm is held up in the "valve open" position by a magnet attracting a soft ferromagnetic armature. The armature can be displaced to release the flapper to close the valve, either by seismic accelerations or manually by novel magnetic means--the latter for testing or for non-seismic emergencies. The latter employ movable permanent magnets or electromagnets. Additional magnets are provided to hold the valve closed. Indicating means on the flapper shaft can be viewed through a window to see the valve status--open or closed. The electromagnetic modification provides remote status indication via a magnetically-actuated switch.

대표청구항 ▼

[ We claim:] [1.] An automatic safety shutoff valve comprising a body and a flapper arm fixed to a shaft and swingable between a downward valve-closed position and an upward valve-open position and having a first flapper arm magnet in its outer portion, and further comprising:an armature of soft fer

[ We claim:] [1.] An automatic safety shutoff valve comprising a body and a flapper arm fixed to a shaft and swingable between a downward valve-closed position and an upward valve-open position and having a first flapper arm magnet in its outer portion, and further comprising:an armature of soft ferromagnetic material and movable between a normal and a displaced position,said first magnet holding said flapper arm up by attraction to said armature when said armature is in said normal position, and when in said displaced position releasing said arm to swing downward to said valve-closed position, andcontrollable magnetic means to raise said armature upward to a said displaced position to effect emergency closure of said valve; and further comprising:a second magnet in said arm adjacent to its inner end near said shaft, anda third magnet in said body disposed to attract said second magnet to hold said valve closed when said arm is in said valve-closed position.