Patent ID: 7287711

Claim:
A sprinkler, comprising: a riser; a nozzle rotatably mounted at a top of the riser for ejecting a stream of water; a turbine mounted in the riser; and a drive mechanism mounted in the riser and connecting the turbine and the nozzle, the drive mechanism including a gear train reduction connected to a set of gears pivotably engageable with a bull gear assembly to thereby rotate the nozzle in opposite directions, a resilient shift dog connected to pivot the set of gears, the shift dog being movable to pivot the set of gears upon engagement of the shift dog with a fixed arc adjustment tab and a movable arc adjustment tab, both arc adjustment tabs having a saw tooth configuration, the position of the movable arc adjustment tab being adjustable from an upper end of the riser to select oscillating rotation or full circle rotation of the nozzle, and the shift dog being flexed in an axial direction to allow the arc adjustment tabs to be forced past the shift dog.