Patent ID: 6976543

Claim:
A low pressure, extended coverage, upright fire protection sprinkler, suitable for use in protection of at least extra hazard and high piled storage occupancies, in accordance with the 1999 Edition of NFPA 13, the sprinkler comprising: a body defining an internal passageway extending between an inlet end and an opposite outlet end, the internal passageway having a K-factor of greater than about 16.0, where the K-factor equals an average flow of water in gallons per minute through the internal passageway divided by a square root of pressure of water fed into the inlet end of the internal passageway in pounds per square inch gauge, the outlet end having an axis; a deflector mounted to the body by at least one support arm extending from the body and in alignment with the axis and spaced from the outlet end of the internal passageway, at a fixed position in relation to the outlet with an inner surface of the deflector opposed to flow of water in a first direction from the outlet end of the internal passageway towards a ceiling, the inner surface of the deflector configured and arranged to deflect flow of water generally radially outwardly and downwardly of the sprinkler in a second direction opposite the first direction over a protection area of at least 100 square feet; and a thermally-responsive closure assembly mounted in a manner to secure the outlet end of the internal passageway against flow of water in a non-fire condition and to release in response to a predetermined temperature condition indicative of a fire to permit flow of water from the outlet end of the internal passageway, the thermally-responsive closure assembly including a closure element and a heat-responsive trigger mounted to releasably secure the closure element at the outlet end of the internal passageway, the heat-responsive trigger having a response time index of at least about 15 meter 1/2 sec 1/2 (m 1/2 s 1/2 ) and less than about 120 meter 1/2 sec 1/2 (m 1/2 s 1/2 ).