Patent ID: 8172001

Claim:
A pendent residential fire prevention sprinkler comprising: a sprinkler body, having an inlet and an outlet and an axial passage from said inlet to said outlet, said inlet being to receive in-flowing fire-extinguishing fluid and said outlet being to deliver the fluid from said body; means for blocking and unblocking said outlet to prevent the fluid from passing through said outlet, said means being for blocking said outlet until occurrence of a predetermined condition and for unblocking said outlet in response to occurrence of the condition; a frame structure extending from said sprinkler body; and a deflector, supported by said frame structure at a predetermined distance from said outlet, at a position to be impinged upon by the fluid leaving said outlet upon said outlet being unblocked, said deflector having a central portion and a peripheral portion, said peripheral portion having a number of slots extending from an open end, at the periphery of said deflector, generally toward said central portion, and each having a closed end, said slots including a first plurality of slots each of which extends inward from the periphery of said deflector with a first, uniform width between the periphery and said closed end of that slot, and said closed ends of said first plurality of slots narrowing from said first, uniform width to zero width, and said slots including a second plurality of slots each of which has a first portion and a second portion between the periphery of said deflector and said closed end portion of that slot, said first portion having a width that varies at different points within said portion, and said second portion having a uniform width, wherein said first portion is radially outward from said second portion from said central portion of said deflector.