Rotary sprinkler having selectable area coverage

A rotary sprinkler comprising:

• a base;
• a stem mounted on said base for rotation relative thereto, said stem having an inlet for receiving a pressurized water supply;
• a water discharge nozzle mounted on said stem and being rotatable together therewith relative to said base;
• water driven drive means for rotating said stem relative to said base;
• sprinkling pattern determining means including
• selectably positionable deflector means for engaging a stream of water emitted by said nozzle for determining the maximum radius of the stream, said deflector means including a first element movably mounted on said stem, a second element defining a water stream engaging portion and a pattern definition cam following element;
• predetermined pattern definition cam means operative, in cooperation with said pattern definition cam following element, when said sprinkler is arranged for operation in a first mode of operation to modulate the position of said deflector means in accordance with the azimuthal orientation of the nozzle according to a predetermined pattern;
• function selection cam means including manually engageable means for selecting the mode of operation of said sprinkler from among a first mode wherein said pattern definition cam means is operative to modulate the position of said deflector means in accordance with said predetermined pattern and a second mode wherein said pattern definition cam means is not operative to modulate the position of said deflector means.