Large volume sprinkler head with part-circle step by step movements in both directions

In a sprinkler head comprising a sprinkler body having an inlet and an outlet, means for mounting said sprinkler body for controlled rotational movement about a generally vertical axis with said inlet in communication wtih a conduit arranged to communicate a source of water under pressure therewith, said outlet being disposed to direct water under pressure communicated with said inlet in a stream flowing therefrom in a direction upwardly and outwardly with respect thereto in generally symmetrical relation to a plane passing through the axis of rotation, an impulse arm, means pivotally mounting said impulse arm with respect to said sprinkler body (1) for pivotal movement about an axis disposed within said plane between a selected first or second operating position and (2) for operative oscillating movement about an axis extending transverse to said plane, said impulse arm having a drive spoon operable when said impulse arm is in said first and second operating positions respectively for effecting rotational movements of said sprinkler body in clockwise and counter clockwise directions respectively, said impulse are being normally biased toward an oscillatory limited position wherein an operable reactant element is disposed within the path of a stream issuing from said outlet a predetermined maximum extent and being operable in response to the energy of a stream issuing from said outlet to move through repeated oscillatory cycles each of which includes an impulse stroke wherein said operable reactant element leaves the stream and moves away from the latter in one direction and a return stroke wherein said operable reactant element moves in the opposite direction toward said stream and enters the latter, and means operable (1) when said impulse arm is in said first operating position and said sprinkler body has been rotated clockwise into a first rotational limiting position for changing the selected position of said impulse arm from said first operating position to said second operating position and (2) when said drive spoon is in said second operating position and said sprinkler body has been rotated counter clockwise into a second rotational limiting position for changing the selected position of said impulse arm from said second operating position to said first operating position, the improvement which comprises

• said sprinkler body including an elongated barrel leading to said outlet having a longitudinal axis intersecting at an included angle greater than 90.degree. with the rotational axis of said sprinkler body,
• the pivotal axis of said impulse arm being upright and at a position spaced substantially outwardly in a downstream direction from the intersection of said longitudinal axis with said sprinkler body rotational axis,
• said impulse arm mounting means including a yoke pivotally mounted on said barrel about an axis coinciding with the pivotal axis of said impulse arm for movement between first and second operating positions corresponding to the first and second operating positions of said impulse arm and means for pivotally connecting said impulse arm with said yoke about an axis constituting the oscillating axis of said impulse arm,
• the oscillating axis of said impulse are being disposed above the longitudinal axis of said barrel and spaced outwardly of the yoke pivotal axis in a downstream direction.