Patent ID: 8162235

Claim:
An irrigation sprinkler comprising: a housing with an inlet for receiving pressurized fluid for irrigation; a riser mounted to the housing, the riser comprising an outlet for expelling pressurized fluid for irrigation; the riser being capable of reciprocal movement between a retracted position and an elevated position relative to the housing, the riser having a generally cylindrical shape including an increased diameter portion; a wiper seal mounted to the housing, the wiper seal comprising at least a first protruding annular blade, a second protruding annular blade, and a third protruding annular blade; the riser and the housing defining at least in part a first conduit for pressurized fluid flow for irrigation; the riser, the housing, and the wiper seal defining at least in part a first cavity for receiving pressurized fluid flow; wherein the first annular blade and the second annular blade are substantially in contact with the riser throughout the reciprocal movement and do not contact the increased diameter portion; and wherein the third annular blade sealingly engages the increased diameter portion of the riser only when the riser is in the elevated position.