Fire safety valve

Claim 2

A heat-responsive cap assembly for use with a valve having a valve housing and a longitudinally movable stem to lock the stem at a first position and release the stem for movement to a second position responsive to a temperature in excess of a predetermined value, said assembly comprising: cap means engageable with said valve housing at the free end of said stem of said valve; and fusible means in said cap means between said stem and said cap means retaining said cap means in engagement with said housing whereby said cap means holds said valve stem at said first position, said fusible means being adapted to release said cap means from engagement with said valve housing responsive to a force applied by said valve stem when the temperature of said fusible means exceeds a predetermined value, said fusible means comprising a body of fusible material within said cap assembly and having a surface engageable with an end face of said valve stem and said fusible material being extrudable from said cap assembly above said predetermined temperature to release said stem for movement to said second position.

Claim 3

A cap assembly in accordance with claim 1 wherein said cap comprises a cylindrical body having a bleed port in an end face thereof and said fusible means comprises a body of fusible material in cylindrical form disposed within said cap between said bleed port and an end face of said valve stem when said assembly is engaged on said valve housing.

Claim 4

A cap assembly in accordance with claim 2 said fusible means further including a non-fusible plate member in said cap adjacent to said fusible material for applying force from an end face of said valve stem to said fusible material.

Claim 5

A cap assembly for use with a valve having a valve housing and a longitudinally movable stem for engagement with said stem to hold said stem at a first position and operable responsive to a predetermined temperature to release said valve stem for movement to a second position, said cap assembly comprising: an annular ring engageable on said valve housing around said stem at the free end of said stem; radially movable latch members within said ring adapted to move between stem locking and stem release positions; and fusible means within said ring for holding said latch members at said stem locking positions and releasing said latch members responsive to a predetermined high temperature to permit said members to move to said stem release positions.

Claim 6

A cap assembly for use with a valve having a valve housing and a longitudinally movable stem for engagement with said stem to hold said stem at a first position and operable responsive to a predetermined temperature to release said valve stem for movement to a second position, said cap assembly comprising: an annular ring engageable on said valve housing around said stem at the free end of said stem; radially movable latch members within said ring adapted to move between stem locking and stem release positions; and fusible means within said ring for holding said latch members at said stem locking positions and releasing said latch members responsive to a predetermined high temperature to permit said members to move to said stem release positions.

Claim 7

A cap assembly in accordance with claim 4 including a stem locking member within said ring for holding said stem at said first position when said latch members are at said stem locking positions and releasable by said latch members when said latch members move to said stem release positions to release said valve stem for movement to said second position.

Claim 8

A cap assembly in accordance with claim 5 wherein said latch members comprise locking balls.

Claim 9

A cap assembly in accordance with claim 5 wherein said latch members comprise arcuate circular segments.

Claim 10

A cap assembly in accordance with claim 7 wherein said annular ring has an inner annular recess and radial bleed ports communicating with said recess; said fusible means comprises an annular ring of fusible material within said inner recess of said annular ring; and said circular segments are disposed within said inner recess of said annular ring inwardly of said ring of fusible material; and including a valve stem locking plate releasably held within said circular segments for engaging the free end face of said valve stem for holding said valve stem at said first position and for releasing said valve stem for movement to said second position responsive to said predetermined high temperature effecting disintegration of said fusible ring permitting said segments to move radially outwardly releasing said valve stem locking plate.

Claim 11

A cap assembly for use with a valve having a valve housing and a longitudinal movable stem for engaging said stem to hold said stem at a first position and for releasing said stem for movement to a second position responsive to a predetermined high temperature, said assembly comprising: an annular ring adapted to be secured on said valve housing around the free end of said valve stem, said ring having an inner annular recess; an internal cap having a cylindrical side skirt and an eNd face provided with a bleed port, said skirt being insertable into said annular ring and having circumferentially spaced radial bores alignable with said recess in said ring when said cap is in operating holding position in said ring; a valve stem holding member within said inner cap and movable within said cap between a valve stem holding position and a valve stem release position, said member having an external annular recess alignable with said radial bores in said inner cap at said valve stem release position; a fusible body disposed in said inner cap between the internal end face of said cap and said valve stem holding member for holding said member at said first valve stem locking position; and radially movable locking balls in said radial bores of said inner cap, said balls being held at a first outward position in said bores projecting into said inner recess of said annular ring when said valve stem locking member is at said holding position and said balls being movable inwardly into said external recess of said valve stem holding member when said member is at said release position, said balls releasing said inner cap for movement in said annular ring to release said valve stem, said fusible material being adapted to disintegrate at a predetermined high temperature to release said valve stem holding member for movement to said release position.

Claim 12

A cap assembly for use with a valve having a valve housing and a longitudinal movable stem for engaging said stem to hold said stem at a first position and for releasing said stem for movement to a second position responsive to a predetermined high temperature, said assembly comprising: an annular ring adapted to be secured on said valve housing around the free end of said valve stem, said ring having an inner annular recess; an internal cap having a cylindrical side skirt and an eNd face provided with a bleed port, said skirt being insertable into said annular ring and having circumferentially spaced radial bores alignable with said recess in said ring when said cap is in operating holding position in said ring; a valve stem holding member within said inner cap and movable within said cap between a valve stem holding position and a valve stem release position, said member having an external annular recess alignable with said radial bores in said inner cap at said valve stem release position; a fusible body disposed in said inner cap between the internal end face of said cap and said valve stem holding member for holding said member at said first valve stem locking position; and radially movable locking balls in said radial bores of said inner cap, said balls being held at a first outward position in said bores projecting into said inner recess of said annular ring when said valve stem locking member is at said holding position and said balls being movable inwardly into said external recess of said valve stem holding member when said member is at said release position, said balls releasing said inner cap for movement in said annular ring to release said valve stem, said fusible material being adapted to disintegrate at a predetermined high temperature to release said valve stem holding member for movement to said release position.