Alignment means for mobile irrigation apparatus

Claim 1

A mobile irrigation apparatus comprising an elongate horizontally disposed water distributing pipe, an inlet at one end for the introduction of water under pressure, a plurality of discharge nozzles spaced along said distributing pipe between its ends for spraying water as the distributing pipe is carried over the land, a main mobile support adjacent the other end of the distributing pipe and means mounting a portion of the distributing pipe thereon for support and for movement therewith, a plurality of intermediate mobile supports in laterally spaced apart relation along the length of the distributing pipe between the inlet end and the main mobile support for support of the distributing pipe at corresponding laterally spaced apart portions, individual motor drive means on each support for actuation of the mobile supports individually for movement in the forward or rearward directions, means for maintaining alignment between the intermediate supports and the main support during continuous operation of the main support in the forward or rearward direction comprising a flexible cable extending substantially parallel to the distributing pipe from the inlet end to the main support and attached thereto, means on each intermediate support for controlling operation of the motor drive means on the respective intermediate support, and switch means having switch operating elements in position to be responsive to the cable to discontinue operation of the drive means in response to movement of the intermediate support out of alignment with the main or adjacent supports to a position a predetermined distance in advance in the direction of movement of the main support to discontinue operation of the power operated drive means and to initiate operation of the motor drive means responsive to return of the intermediate support into position of alignment whereby it continues to travel with the main support in the direction of movement thereof while in alignment therewith.