Flush type sprinkler head

Claim 1

A flush type sprinkler head comprising: a vertical cylindrical main body having in an upper portion thereof external threads for threadable engagement with a piping in the ceiling of a building, in a lower portion thereof internal threads and in a central portion thereof an axially extending nozzle provided with a valve seat at the lower end of said nozzle; a cylindrical frame engaging said valve seat and having at the lower end a radially inwardly extending flange and in an upper portion external threads for threadable engagement with said internal threads of said main body; a valve member normally abutting against said valve seat to close said nozzle; a deflector assembly slidably received within said frame surrounding said valve member for downward movement relative to the frame by a first predetermined distance and including a guide ring, a plurality of slide bars extending downwardly from said guide ring and a circular deflector fitted on said valve member for downward movement together with the valve member and relative to the frame along said slide bars by a second predetermined distance which is greater than said first predetermined distance; a compressed conical coil spring interposed between the undersurface of said main body and the upper surface of said guide ring and adapted to bias said valve member and slidable deflector assembly downwardly upon the operation of said sprinkler head; and a break-up assembly positioned below said slidable deflector assembly and adapted to explode into pieces upon the operation of said sprinkler head.