US3901442A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Suspension distribution system
Assignee: Valmont Industries Inc
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Filing: 1974-08-19
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Granted: 1975-08-26
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Expires: 1994-08-19
Abstract
Abstract A center pivot agricultural liquid distribution system for distributing a liquid suspension containing solid particles substantially uniformly over a segmental circular area traced by an elongated distribution conduit extending radially from a central pivot point in a field, a limited number of discharge nozzles, each larger than the maximum size particle, are located at spaced intervals along the conduit, each nozzle having an actuator to open and close the nozzle. A control operates the nozzle actuators in accordance with a repetitive timing cycle; the innermost nozzle is open for only a brief interval, the open intervals being progressively longer for successive outwardly displaced nozzles.
Inventors
- 👤 John A Chapman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:18
CPC Classifications
A; A01; A01G; A01G25/00; A01G25/09; A01G25/092; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86389; Y10T137/86445
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
230 words
A center pivot agricultural liquid distribution system, of the kind comprising an elongated distribution conduit extending radially from a central pivot point in a field and drive means for pivoting the conduit about the pivot point to sweep at least a segmental circular area of the field, capable of substantially uniform distribution of a liquid suspension containing solid particles of given maximum dimension over the field area swept by the conduit, comprising: a limited number of discharge nozzles mounted on and connected to the conduit at predetermined axially spaced intervals, each adapted to spray the liquid suspension outwardly of the conduit, the spray pattern of each nozzle extending at least to the edge of the spray pattern for the next adjacent nozzle, each discharge nozzle having an internal diameter larger than the aforesaid maximum particle dimension; a corresponding number of nozzle actuators, one actuator being connected to each discharge nozzle to actuate that discharge nozzle between an open discharge condition and a closed condition; and control means for operating the nozzle actuators in accordance with a repetitive timing cycle in which the first discharge nozzle, nearest the pivot point, is maintained in its open discharge condition for a limited incremental portion of each cyclic period, and each successive nozzle, outwardly of the pivot point, is maintained in its open discharge condition for a progressively longer portion of the cyclic period.
Claim 2
Dependent Claim
230 words
A center pivot agricultural liquid distribution system, of the kind comprising an elongated distribution conduit extending radially from a central pivot point in a field and drive means for pivoting the conduit about the pivot point to sweep at least a segmental circular area of the field, capable of substantially uniform distribution of a liquid suspension containing solid particles of given maximum dimension over the field area swept by the conduit, comprising: a limited number of discharge nozzles mounted on and connected to the conduit at predetermined axially spaced intervals, each adapted to spray the liquid suspension outwardly of the conduit, the spray pattern of each nozzle extending at least to the edge of the spray pattern for the next adjacent nozzle, each discharge nozzle having an internal diameter larger than the aforesaid maximum particle dimension; a corresponding number of nozzle actuators, one actuator being connected to each discharge nozzle to actuate that discharge nozzle between an open discharge condition and a closed condition; and control means for operating the nozzle actuators in accordance with a repetitive timing cycle in which the first discharge nozzle, nearest the pivot point, is maintained in its open discharge condition for a limited incremental portion of each cyclic period, and each successive nozzle, outwardly of the pivot point, is maintained in its open discharge condition for a progressively longer portion of the cyclic period.
Claim 3
Dependent Claim
74 words
A center pivot agricultural liquid distribution system according to claim 1 in which the nozzles are equally spaced along the distribution conduit, in which the cyclic period includes a series of equal time increments at least equal in number to the number of nozzles, and in which each successive nozzle is maintained in its open discharge condition for at least one more time increment in each cyclic period than the next adjacent inward nozzle.
Claim 4
Dependent Claim
37 words
A center pivot agricultural liquid distribution system according to claim 2 in which all discharge nozzles have substantially equal limiting internal diameters and flow capacity, and distribute the liquid suspension over bands of Approximately equal radial dimensions.
Claim 5
Dependent Claim
40 words
A center pivot agricultural liquid distribution system according to claim 3, in which a constant number of nozzles, substantially less than the total number of nozzles, is maintained in open discharge condition during each time increment of the operating cycle.
Claim 6
Dependent Claim
33 words
A center pivot agricultural liquid distribution system according to claim 4, in which the number T of time increments in each operating cycle is determined at least approximately in accordance with the relation
Claim 7
Dependent Claim
44 words
A center pivot agricultural liquid distribution system according to claim 4 in which the outermost nozzle actuator is continuously operated to maintain the outermost nozzle in its open discharge condition, allowing constant flow through the outermost discharge nozzle when the system is in use.
Claim 8
Dependent Claim
48 words
A center pivot agricultural liquid distribution system according to claim 4 in which the first discharge nozzle is displaced outwardly of the center pivot by a distance sufficient to leave a limited untreated area, around the center pivot, that does not receive a distribution of the liquid suspension.
Claim 9
Dependent Claim
62 words
A center pivot agricultural liquid distribution system according to claim 7 in which the untreated area has a radius of one-half the radial dimension of the band covered by the first discharge nozzle, so that the effective area ratio of the bands actually covered by the discharge nozzles, outwardly of the center pivot, corresponds to the series 1:2:3:4:5:6:7 . . . .
Claim 10
Dependent Claim
59 words
A center pivot agricultural liquid distribution system according to claim 8 in which the interval during which the first discharge nozzle is open is a given number of time increments in each operating cycle, and each successive nozzle is maintained in its open discharge condition for the same number of time increments more than the next adjacent inward nozzle.
Claim 11
Dependent Claim
92 words
A center pivot agricultural liquid distribution system according to claim 4 in which the innermost nozzle distributes the liquid suspension in a band that extends to the center pivot, and in which the limited incremental portion of the cyclic period for the first discharge nozzle is a given number of time increments, and each successive nozzle is maintained in its open discharge condition for twice that number of time increments more than the next adjacent inward nozzle, in accordance with an area and time increment ratio of 1:3:5:7:9 . . . .
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |