Abstract: An improved gear drive sprinkler has a pop-up spray head adapted for adjustable part-circle or full circle operation to deliver irrigation water over a selected terrain area. The sprinkler includes a pop-up riser; a gear drive transmission mounted within the riser includes a water-driven turbine for rotatably driving a speed reduction gear train, which in turn rotatably drives the spray head. A reverse assembly includes an upper trip unit defining an individually adjustable pair of end trip stops, and a lower shift mechanism including a shiftable director plate having first and second sets of angularly oriented jet nozzles for respective alignment with turbine jet ports for respectively driving the water-driven turbine and the gear train in a forward-drive or a reverse-drive direction. The upper trip is coupled to the director plate by an elongated trip rod which shifts the director plate between forward-drive and reverse drive positions.

Abstract: An improved gear drive sprinkler has a pop-up spray head adapted for adjustable part-circle or full circle operation to deliver irrigation water over a selected terrain area. The sprinkler includes a pop-up riser having a rotatable spray head mounted at an upper end thereof. A gear drive transmission mounted within the riser includes a water-driven turbine for rotatably driving a speed reduction gear train which in turn rotatably drives the spray head. A reverse assembly includes an upper trip unit defining an individually adjustable pair of end trip stops, and a lower shift mechanism including a shiftable director plate having first and second sets of angularly oriented jet nozzles for respective alignment with turbine jet ports for respectively driving the water-driven turbine and the gear train in a forward-drive or a reverse-drive direction.