Patent ID: 7500620

Claim:
A telescoping pop-up sprinkler connectable with a source of pressurized fluid, the telescoping pop-up sprinkler head comprising: a tubular main body with an upper end and a lower connector end, the upper end having external threads, and the lower connector end being adapted to receive pressurized fluid; a telescoping piston assembly disposed in the tubular body, the telescoping piston assembly including a primary piston and a secondary piston engaged together in telescoping, sliding relationship; the primary piston having a tubular body with an upper end and a lower end, the upper end being internally threaded, and the lower end having a retaining flange, a primary spring disposed over the tubular body of the primary piston, and an annular pressure activated primary seal disposed over the tubular body of the primary piston in the tubular main body; a spring retainer disposed over the tubular body of the primary piston between the primary seal and the primary spring to retain the primary spring in position when the telescoping pop-up sprinkler is assembled, and wherein said spring retainer has an annular body with an opening extending through the annular body from an upper side to a lower side of the annular body, said opening having a clearance sufficient to allow water pressure to activate the pressure activated primary seal during operation of the sprinkler; the secondary piston having a tubular body with an upper end and a lower end, and the lower end having a retaining flange, a secondary seal disposed over the tubular body of the secondary piston within the tubular body of the primary piston, and a secondary spring disposed over the tubular body of the secondary piston between the retaining flange of the tubular body of the secondary piston and the annular internal stop of the tubular body of the primary piston; and a cap disposed on the upper end of the tubular main body retaining the primary seal in the tubular main body.