Abstract: A vandal resistant part circle gear driven sprinkler having a plastic pop-up assembly including a nozzle housing rotatably mounted to a non-rotatable pop-up stem within which a reversible gear drive mechanism is mounted. A slip clutch is provided for mounting the reversible gear drive mechanism within the stem to prevent relative rotation during normal sprinkler operation, but which permits the mechanism to rotate relative to the stem whenever an external torque above a preselected level is applied to the nozzle housing.

Abstract: An improved rotary drive sprinkler is provided for rotatably driving a pop-up spray head in a stepwise manner through a full-circle or reversibly within a selected part-circle path. The sprinkler includes a reversing trip mechanism having a pair of spaced-apart stops rotatable with the spray head and defining preset end limits of a part-circle path, wherein a stationary trip wire is engageable with the stops to switch an internal rotary drive assembly, such as a ball drive assembly, between forward- and reverse-drive operation. The trip wire flexes to accommodate forced spray head rotation to a maladjusted position beyond the end limits and, upon subsequent sprinkler operation, rides over ramped surfaces on the stops for automatic return to reversible operation between the preset end limits. Alternatively, the stops can be set in side-by-side relation with their ramped surfaces oriented for the trip wire to ride resiliently thereover without switching of the rotary drive assembly.

Abstract: An improved rotary drive sprinkler is provided for rotatably driving a pop-up spray head in a stepwise manner through a full-circle or reversibly within a selected part-circle path. The sprinkler includes a reversing trip mechanism having a pair of spaced-apart stops rotatable with the spray head and defining preset end limits of a part-circle path, wherein a stationary trip wire is engageable with the stops to switch an internal rotary drive assembly, such as a ball drive assembly, between forward- and reverse-drive operation. The trip wire flexes to accommodate forced spray head rotation to a maladjusted position beyond the end limits and, upon subsequent sprinkler operation, rides over ramped surfaces on the stops for automatic return to reversible operation between the reset end limits. Alternatively, the stops can be set in side-by-side relation with their ramped surfaces oriented for the trip wire to ride resiliently thereover without switching of the rotary drive assembly.