Center pivot irrigation system

• US 6,007,004 A
• Filed: 09/14/1998
• Issued: 12/28/1999
• Est. Priority Date: 09/14/1998
• Status: Expired due to Term

• Current Assignee: Valmont Industries Incorporated
• Original Assignee: Valmont Industries Incorporated
• Inventors: Unruh, Rudy R.
• Primary Examiner(s): Kashnikow, Andres
• Assistant Examiner(s): Ganey, Steven J.
• Application Number:
  US09/152,400
• Time in Patent Office: 470 Days
• Field of Search: 239/69, 239/71, 239/73, 239/DIG. 1, 239/726, 239/728, 239/729, 239/730, 239/731, 239/733, 239/743, 239/744, 239/739
• US Class Current: 239/729
• CPC Class Codes: A01G 25/092 movable around a pivot centre

Abstract

An irrigation system is disclosed which includes a center pivot support having an elongated main water boom pivotally connected thereto which extends outwardly therefrom. A corner span is pivotally connected at its inner end to the outer end of the main boom and is supported by a steerable drive tower. An angle sensor is provided at the pivotal connector of said main boom and said corner span. A span sensor is positioned on the corner boom for sensing shape changes in the corner span. A control connects the span sensor and angle sensor with the drive and steering for driving and steering the steerable drive tower. The control means, when said extension boom is in a trailing position, actuates said steering means to follow the guidance means and actuating said speed control to maintain the shape of the corner span within predetermined parameters; said control means, when the corner span approaches full extension, actuates said speed control to keep the corner span in alignment with the main boom, as determined by the angle sensor and actuating said steering means to maintain the shape of the corner span within predetermined parameters as determined by the span sensor.

Claims

1. An irrigation system, comprising:

a center pivot support structure;

an elongated main water boom, having inner and outer ends, pivoted at its inner end to said center pivot support structure and extending outwardly therefrom;

said main water boom comprising an elongated main water pipe supported upon a plurality of non-steerable drive towers which propel said main water pipe around said center pivot support structure;

said non-steerable drive towers including a last regular drive tower;

a corner span, having inner and outer ends, pivotally connected at its said inner end to said outer end of said main boom;

said corner span comprising an elongated extension water pipe supported upon at least one steerable drive tower;

steering means for steering said steerable drive tower;

drive means for driving said steerable drive tower;

guidance means for controlling said steering means so that said steerable drive tower is moved along a preselected path, as said main boom travels over the field to be irrigated, thereby causing said extension boom to pivotally move with respect to said main boom to cause said extension boom to pivotally extend out into corner areas of the field and pivotally retract therefrom as said main boom travels through the field;

a span sensor positioned on said extension water pipe for sensing shape changes in said corner span;

an angle sensor at the pivotal connection of said main boom and said corner boom for sensing the angle therebetween;

control means connecting said span sensor, said angle sensor, said steering means and said drive means for adjusting the speed and steering of the said steerable drive tower;

said control means, when said extension boom is in a trailing position, actuating said steering means to follow the guidance means and actuating said speed control to maintain the shape of said corner span within predetermined parameters;

said control means, when said corner span approaches full extension, actuating said speed control to keep the corner span in alignment with said main boom, as determined by said angle sensor, and actuating said steering means to maintain the shape of said corner span within predetermined parameters as determined by said span sensor.