Patent attributes
A rotary, nutating sprinkler head includes a housing supporting a nozzle; a starter tube axially adjacent the nozzle and extending in a downstream direction, concentric with a vertical center axis of the sprinkler head. A spool assembly is loosely supported on the starter tube, the spool assembly including a double-flanged spool and a water-deflection plate carried by the spool, the water-deflection plate formed with one or more grooves shaped to cause the spool assembly to rotate when impinged upon by a stream emitted from the nozzle. Either the starter tube or the spool is provided with at least one tilting lug located to keep the spool assembly in a tilted or angularly offset orientation relative to the vertical center axis, thereby facilitating a wobbling action of the spool assembly during rotation.