Patent US4431338A successfully refreshed from Google Patents.
US4431338A
Expired / Lapsed
US
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Irrigation monitoring system
Assignee: Individual
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Filing: 1981-02-26
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Granted: 1984-02-14
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Expires: 2001-02-26
Abstract
Abstract An irrigation system in which a main channel is connected to a series of irrigation bays by separate distribution channels and the flow of water to each bay is controlled centrally in response to the moisture content in each bay. The bays are irrigated in sequence by a central control system.
Inventors
- 👤 Graham A. Hornabrook
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:51
CPC Classifications
E; E02; E02B; E02B13/00
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
177 words
An irrigation system for irrigating a plurality of irrigation bays, said system including a main channel having a supply of water, a separate distribution channel connecting each bay to the main channel, flow control means for each distribution channel operative to initiate and cease the flow of water to its irrigation bay, sensing means in each bay for sensing a pre-determined moisture content at a pre-selected location in each bay and central control means operative to activate each flow control means in sequence so as to initiate flow of water to each bay in sequence and operative to de-activate each flow control means in response to a signal received from the sensing means indicating that the pre-determined moisture content in that bay has been reached, each said sensing means including a radio transmitter transmitting a signal which is characterized as being uniquely associated with the sensor from which it is related, said characterization comprising amplitude, frequency or pulse modulation whereby each point at which a sensor is located is identifiable by the particular radio signal transmitted therefrom.
Claim 2
Dependent Claim
177 words
An irrigation system for irrigating a plurality of irrigation bays, said system including a main channel having a supply of water, a separate distribution channel connecting each bay to the main channel, flow control means for each distribution channel operative to initiate and cease the flow of water to its irrigation bay, sensing means in each bay for sensing a pre-determined moisture content at a pre-selected location in each bay and central control means operative to activate each flow control means in sequence so as to initiate flow of water to each bay in sequence and operative to de-activate each flow control means in response to a signal received from the sensing means indicating that the pre-determined moisture content in that bay has been reached, each said sensing means including a radio transmitter transmitting a signal which is characterized as being uniquely associated with the sensor from which it is related, said characterization comprising amplitude, frequency or pulse modulation whereby each point at which a sensor is located is identifiable by the particular radio signal transmitted therefrom.
Claim 3
Dependent Claim
43 words
An irrigation system as claimed in claim 1 wherein the control means includes a programmable radio transmitter and receiver which broadcasts signals to a receiver at each flow control means, each receiver being operative to control the operation of its flow control means.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-02-13 | 1987-08-15 | 1988-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-13 | 1991-08-15 | 1992-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-13 | 1995-08-15 | 1996-02-14 | $7700.00 | Window Closed / Lapsed |