Abstract: A pop-up sprinkler which includes a housing, a riser in the housing movable between an extended position in which the riser extends from the housing and a retracted position in which the riser is retracted from the extended position and a pressure regulator in the riser. The pressure regulator can be constructed as a cartridge or separate unit and installed in the riser. The riser has an aperture adjacent the pressure regulator and the aperture is between first and second axially spaced seals in the extended position so as to reduce the likelihood of clogging of the aperture. A dirt tolerant wiper seal is mounted on a movable valve tube of the pressure regulator and a pressure activated seal is provided between a valve seat of the pressure regulator and the valve tube.

Abstract: A sprinkler includes a pop-up stem that defines a passage extending to a downwardly facing opening that is circumscribed by a generally planar surface and covered by a valve element dimensioned and arranged in confronting relationship with the planar surface to at least partially block the opening. The valve element is mounted on the stem to enable movement in a plane generally parallel to the planar surface in order to vary an amount by which the valve element blocks the opening, and rotation of a shaft causes valve element movement to restrict the flow of liquid through the opening a selected amount. A resiliently deformable valve element may be loosely mounted to provide clearance sufficient to enable movement of particulate material from between the valve element and the planar surface while enabling the liquid to urge the valve element toward the planar surface.