Rotating stream sprinkler

Abstract

A rotating stream sprinkler is provided with an improved spray head for sweeping one or more outwardly projected water streams through a prescribed arcuate spray path, wherein the spray head is adapted for enhanced self-flushing operation to prevent accumulation of grit and the like which could otherwise impair sprinkler performance. In the preferred form, the spray head is mounted at the upper end of a pop-up stem for movement to an elevated spraying position upon supply of water under pressure to the sprinkler. The water flows to the spray head and normally pressure-loads a plurality of valve balls onto a respective plurality of seats to prevent water flow through the seats to associated nozzle passages. A drive assembly rotates the spray head relative to a nonrotating cam positioned to lift one or more of the valve balls from their respective seats to permit outward discharge of one or more water streams through the nozzle passages, within the limits of the prescribed arcuate path. In a preferred construction, the drive assembly includes a rotatable turbine driven by water inflow to the sprinkler and further includes drive balls for rotating the spray head in a stepwise manner. The turbine is also designed for improved operational reliability particularly when used with water having a significant amount of grit particles therein.