Fluid sprinkling – spraying – and diffusing – Mobile distributor – Irrigation device
Reexamination Certificate
2000-05-02
2001-09-18
Scherbel, David A. (Department: 3752)
Fluid sprinkling, spraying, and diffusing
Mobile distributor
Irrigation device
C239S069000, C239S097000, C701S050000, C701S210000, C701S215000, C701S216000
Reexamination Certificate
active
06290151
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to center pivot irrigation systems having swing arms for providing water to the comers of a field and more specifically relates to a guidance system that is utilized for controlling the travel of the swing arm on a desired path.
2. Description of the Prior Art
Center pivot irrigation systems have long been known in the art for providing water to large sections of land. A typical center pivot system is capable of irrigating one hundred and sixty acres or more. A center pivot system is formed of a main arm water conduit that is fixed at one end to a central point of water supply. The main arm is supported on a plurality of wheeled towers and is pivotally attached to the source of water to provide a circular irrigation pattern surrounding such supply.
Center pivot irrigation systems have proven to be highly efficient in irrigating large sections of land. They suffer from the deficiency that they produce a circular water pattern, although most fields are either rectangular or square shaped. Accordingly, a center pivot system by itself will not be able to provide water to the comers of a field, resulting in decreased production or complete loss of production therein. To increase the amount of area that can be watered by a center pivot system, high pressure sprayers known as end guns have been mounted on the end of the center pivot main arm and are actuated at the comers to produce a water spray into only a portion of the comers. Due to this fact, end guns are not an effective or efficient method for watering the comers and improved corner watering systems have been desired.
In the 1970's, the use of an additional watering arm (called a swing arm) was begun, with the swing arm being pivotally attached to the free end of the main arm to pivot out into the comers as desired. A variety of different methods for steering and driving the swing arm have been developed, but the most successful and predominantly used system for controlling the movement of the swing arm is through the use of an electromagnetically charged cable that is buried in the ground along the path that the swing arm is desired to follow. See U.S. Pat. No. 3,902,668 to Daugherty, et al.
Through the use of buried cable controls, swing arm center pivot irrigation systems have been improved in efficiency and operation. Nevertheless, there are certain drawbacks in such systems, particularly in instances where the topsoil of a field may overlie a rock substrata. In view of the fact that a buried cable system requires the laying of ten thousand or more feet of cable, when rock is present in a field, installation of the buried cable becomes unusually difficult and expensive. It is also very expensive to repair or to alter the path of the system once the cable is buried.
Other methods used to steer the swing arm include the use of encoders and angle comparisons or electrical control means with banks of switches and settings for the desired paths. See U.S. Pat. No. 4,340,183 to Kegel and U.S. Pat. No. 3,797,517 to Kircher, respectively.
Until recently the use of Global Positioning Satellite (GPS) data to guide the swing arm of a center pivot irrigation system would have been impractical from the standpoint that such position calculations were too inaccurate and GPS receiver/senders were prohibitively expensive.
The present invention is designed to provide a new and improved guidance system for the steering control of a swing arm on a center pivot system that overcomes the deficiencies of the prior art.
SUMMARY OF THE INVENTION
The present invention is a guidance system for providing a steering control for a swing arm on a center pivot irrigation system having a main arm water conduit with one end pivotally connected to a known central point of water supply at a known location and supported on at least one movable tower. The system includes a first satellite signal receiving means for producing position information representative of the calculated position of the known central point and a comparator means for comparing the known position of the central point with the calculated position information of said point and then generating an error signal representative of the difference therebetween.
A second satellite signal receiving means is located on the swing arm for producing position information representative of the calculated position of the swing arm. A first processing means is employed for using the error signal produced by the comparator means to adjust the position information produced by the second signal receiving means to generate corrected swing arm position information.
In a first preferred embodiment the corrected swing arm position information is sent to a second processing means where position information representative of the desired path of travel of the swing arm is stored and the corrected position information is compared to said desired path of travel information, producing therefrom a steering signal for the swing arm.
In a second preferred embodiment, a virtual position at a distance ahead of the actual position of the second satellite signal receiving means is calculated and used rather than its actual position. This allows the swing arm direction to be adjusted in a more timely manner and results in more tangential movement and more accurate positioning of the swing arm on the desired path of travel.
The foregoing and other advantages of the present invention will appear from the following description. In the description, reference is made to the accompanying drawings, which form a part hereof, and in which there is shown by illustration and not of limitation two specific forms in which the invention may be embodied. Such embodiments do not represent the full scope of the invention, but rather the invention may be employed in a variety of other embodiments and reference is made to the claims herein for interpreting the breadth of the invention.
REFERENCES:
patent: 3797517 (1974-03-01), Kircher et al.
patent: 3902668 (1975-09-01), Daugherty et al.
patent: 4340183 (1982-07-01), Kegel et al.
patent: 4569481 (1986-02-01), Davis et al.
patent: 5334987 (1994-08-01), Teach
patent: 5653389 (1997-08-01), Henderson et al.
patent: 5904296 (1999-05-01), Doherty et al.
patent: 5919242 (1999-07-01), Greatline et al.
patent: 5927603 (1999-07-01), McNabb
patent: 5955973 (1999-09-01), Anderson
patent: 6036122 (2000-03-01), Gerdes et al.
patent: 6045066 (2000-04-01), Gerdes et al.
patent: 6085999 (2000-07-01), Gerdes et al.
patent: 6095439 (2000-08-01), Segal et al.
Barker Luke J.
Neff Darin J.
Ganey Steven J.
Pingel G. Brian
Reinke Manufacturing Company, Inc.
Scherbel David A.
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