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Publication numberUS3402890 A
Publication typeGrant
Publication dateSep 24, 1968
Filing dateMay 25, 1966
Priority dateMay 25, 1966
Publication numberUS 3402890 A, US 3402890A, US-A-3402890, US3402890 A, US3402890A
InventorsHeitzman Charles J
Original AssigneeR & H Molding Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Sequencing sprinkler
US 3402890 A
Abstract  available in
Images(3)
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Claims  available in
Description  (OCR text may contain errors)

Sept. 24, 1968 c. J. HEITZMAN 3,402,390

SEQUENCING SPRINKLER Filed May 25, 1966 3 Sheets-Sheet l Charles J. Heitzmcm y MJMM his Attorney Inventor:

p 24, 1968 c. J. HEITZMAN 3,402,890

SEQUENCING SPRINKLER Filed May 25, 1966 .3 Sheets-Sheet 2 5'8 7 I B y 7 hi's Attorney Sept. 24, 1968 C.J.HEWZMAN SEQUENC ING SPRINKLER Filed May 25, 1966 3 Sheets-Sheet 5 ll FIG. 7

his Attorney United States Patent 3,402,896 SEQUENCING SPRINKLER Charles J. Heitzman, Honolulu, Hawaii, assignor to R&H Molding, Inc, Honolulu, Hawaii, a corporation of Hawaii Filed May 25, 1966, Ser. No. 552,870 14 Claims. (Cl. 239-66) ABSTRACT OF THE DESCLOSURE A programmable sequencing valve for a system having a line to which fluid pressure is supplied at on intervals, the valve including a body connectable to the line and having an outlet, pressure responsive sensing means in the body which on connection of the body to the line is exposed to pressure therein on each on interval, valve means normally closing and operable by the sequencing means for Opening the outlet, a plurality of opening and non-opening sensed elements selectively assemblable in any of a plurality of a series on the body, and means for causing the sensing means on the on intervals sequentially to sense the sensed elements of the selected series and only on sensing of an opening element operate the valve means to open the outlet.

This invention relates generally to sprinkler systems and more particularly to sequencing sprinklers for use in such systems.

The essentials in any sprinkler system are a pipe to each sprinkler and a source of energy to supply water under pressure to the pipe. In small installations involving only a few sprinkers, it usually is practical to connect all of the sprinklers in parallel to the same pipe and operate them simultaneously. However, in a system for irrigating a considerable area, such as that of a sugar cane field, the size of pipe and power required for simultaneous operation of the sprinklers would make the cost prohibitive. It therefore is the practice in larger installations of sprinkler systems to arrang the sprinklers in blocks in each of which several lateral lines each mounting several sprinklers are fed by a mainline and the mainlines in turn branch from and are fed by a supply line from the pump or other energy source. Such a system will not supply sufficient water for simultaneous operation of the sprinklers but it can supply the water required for iirigating the whole area, if only substantially equal fractions of the sprinklers of th several blocks operate simultaneously and that fraction within each block is substantially equally distributed among its lateral lines.

The above operation is obtained by use in the supply line or each mainline, depending on the extent of the installation, of a master or main control valve timed to shut on and off at intervals and, as the sprinklers, of pressure responsive sequencing sprinklers set to operate at predetermined on intervals of the master control valve in the full operating cycle of the system. While some individually programmable sequencing sprinklers have been proposed, the sprinklers usually employed in such sprinkler systems are connected in series and depend for their sequences on their relative positions in the lateral lines, each sprinkling during the first on interval in which water pressure is applied to it and thereafter cutting off its own nozzle and passing the water in succession to the sprinklers following it in the lateral line. Even though not programmable, these sequencing valves will reset themselves for a succeeding sprinkling cycle but depend for their sequence on their relative positions in the lateral lines and for their operation upon the operability of every preceding sprinkler in the same line.

The primary object of the present invention is to provide an improved pressure responsive sequencing sprinkler which not only is programmable for sprinkling during a predetermined interval in the cycle of a sprinkler system without regard to its relative position in a lateral line but, once assembled to suit the cycle of a particular sprinkler system, is programmable at will in situ, without the use of tools, to set its sequence relative to other sprinklers in the same line.

Another object of the invention is to provide a programmable pressure responsive sequencing sprinkler which, in addition to being individually programmable, requires only a readily preformed selective assembly of its sensed elements to adapt it to a wide variety of sprinkler systems.

An additional object of the invention is to provide a programmable pressure responsive sequencing sprinkler, the nozzle of which is so valved as to bar entry of and consequent plugging by insects or other foreign matter during the periods in which it is not actually sprinkling.

A further object of the invention is to provide a programmable pressure responsive sequencing sprinkler, the programming mechanism of which is not only sure and positive in action but so compact as not to interfere with the inclusion of a flapper or other adjunct for enabling the sprinkler to cover an area of circular or other suitable shape.

Other objects and advantages of the invention will appear hereinafter in the detailed description, be particularly pointed out in the appended claims and be illustrated in the accompanying drawings, in which:

FIGURE 1 is a diagrammatic view of an automatic sprinkler system equipped with the sequencing sprinklers of the present invention;

FIGURE 2 is a front elevational view of a preferred embodiment of the sequencing sprinkler of the present invention mounted on a riser, with portions broken away and shown in section to more clearly illustrate certain of the details of construction;

FIGURE 3 is a plan view of the sprinkler of FIGURE 2 taken parallel to the section line '66 shown on that figure;

FIGURE 4 is a fragmentary side elevational view taken perpendicular to the section line 6-6 of FIGURE 2, showing from the side the programming mechanism and its mounting;

FIGURE 5 is a fragmentary and elevational View taken perpendicular to the section line 66 of FIGURE 2, showing the valving for the nozzle;

FIGURE 6 is a fragmentary transverse sectional view on an enlarged scale taken along lines 66 of FIGURE 2 and showing the programming mechanism in its at rest condition;

FIGURE 7 is a partial view of the structure of FIG- URE 6, showing the condition of the mechanism during an on interval in which the sprinkler is not sprinkling;

FIGURE 8 is another partial view of the structure of FIGURE 6 showing the condition of the mechanism in an on interval during which the sprinkler is sprinkling;

FIGURE 9 is a transverse sectional view taken along lines 99 of FIGURE 6;

FIGURE 10 is a transverse sectional view taken along lines Ill-10 of FIGURE 9;

FIGURE 11 is a fragmentary sectional view taken along lines 1111 of FIGURE 9, showing the advancing cam in its at rest position;

FIGURE 12 is a view of the structure of FIGURE 11 with the advancing cam retracted from the ball cage; and

FIGURE 13 is a fragmentary side elevational view on a further enlarged scale of the outlet end of the nozzle, with a portion broken away and shown in section to more clearly illustrate certain of the details of construction.

Referring now in detail to the drawings in which like reference characters designate like parts, the improved pressure responsive sequencing sprinkler of the present invention is designed for use in an automatic sprinkler system in which the sprinklers are caused to operate in predetermined sequences by the periodic interruption of the water supply. Such systems are usually permanent installations for irrigating fields in which sugar cane or other crops are grown. As shown in FIGURE 1, a typical system or installation, designated as 1, will include a water source 2, a pump 3, if the head is insufiicient to provide the required pressure, a supply line 4 from the pump, a plurality of mainlines 5 branching from the supply line and a plurality of lateral lines 6 branching from each mainline. A plurality of the improved sequencing sprinklers 7 are mounted in spaced relation along each of the lateral lines 6 on risers 8.

Depending on the size of the installation, a main control valve 9 will be installed in the supply line 4 in advance of the mainlines 5 or in each of the mainlines in advance of the lateral lines 6. In turn, the one or more control valves 9 and, if present, the pump 3 will be controlled by a timer 10 to operate intermittently in successive on and off intervals, stages or steps, with the on intervals or dwells of such duration as to enable the sprinklers then sprinkling to apply the desired quantity of water to the areas they cover and the off intervals relatively brief. This intermittent operation continues through a full cycle of the system in which all of the sprinklers have operated and the whole field or other area has been ir rigated.

The improved sequencing sprinkler 7 has a body 11 mounting a nozzle or sprinkler head 12, a programming mechanism 13 and a valve 14 controlled by the mechanism for cutting or shutting the nozzle on and off. A central passage or bore 15 through the body 11 from its inlet end 16 to the nozzle 12, connects the latter to the riser 8 on which the particular sprinkler is mounted.

Depending on the pattern of the area it is to irrigate, the sprinkler 7 may be stationarily or movably mounted on the adjoining riser 8 and, if movable, may either rotate or oscillate. The preferred sprinkler 7 is adapted to rotate or swivel about a vertical axis on the riser 8, eject a stream or jet of water upwardly at an oblique angle from the nozzle 12 and turn as it sprinkles so as to irrigate or cover a substantially circular area. Thus, in the illustrated embodiment, the body 11 has an upright or vertical main part or trunk 17 and an arm or branch 18 jutting or projecting upwardly at an oblique angle from the trunk and mounting on its outer end the nozzle 12. A swivel or rotary coupling or union 19 mounted or carried by the trunk 17 below the programming mechanism 13 and threadable or screwable onto the riser 8 provides the desired rotary mounting. A flapper 20 rotatably mounted on a post or boss 21 on the body 11 and upstanding from the trunk 17 above its junction with the arm 18, has a reflector 22 on an end normally disposed in the path of the jet from the nozzle 12 so as to be swung thereby away from the arm, the flapper being swung back by a torsion or other suitable return spring 23 and kicking against a stop lug 24 on the arm for incrementally rotating the sprinkler while it is sprinkling.

The preferred programming mechanism 13 includes a housing 25 formed in part by a cylindrical stem or sleeve 26 projecting radially or horizontally from and rigid or, conveniently, integral with the main part 17 of the body 11, and in balance by a substantially cylindrical cage or casing 27 covering or encircling an outer part of the stern. Disposed vertically and radially of or normal to the stem 26, the cage is releasably held or mounted on the stem between an outwardly facing shoulder 28 thereon and a cap 29 threaded or screwed onto the stems outer end. The cap 29 also closes the outer end of a cylinder 30 in and coaxial with and extending longitudinally of the stem 26 and opening at its inner end through a port 31 onto the central passage 15 in the body 11. The cage 27 contains or encloses a vertically disposed circular or annular raceway 32 concentric with the cylinder 30 and, to expose the raceway, conveniently is separable into an inner, rear or cup member 33, closed except at the front, and an outer or cover member 34 fitting into and closing the front end of the inner member.

Slideable or reciprocable in the cylinder 30 in the stem 26 is a piston 35 having a rod 36 projecting or extending forwardly centrally through the cap 29 and cage 27 and carrying forwardly thereof a shifter or mounting plate or bar 37. Lockable against axial movement on the piston rod 36, as by a set screw 38, in a position in which it abuts against the front end of the cap 29 when the piston 35 is substantially fully retracted in the cylinder 30 toward the passage 15, the shifter plate 37 itself carries or mounts two elements, one a sensing arm or plate 39 and the other in advancing cam 40.

As its sensed elements, the preferred programming mechanism has in series arrangement in the raceway 32 a plurality of balls or ball bearings of two or a plurality of different sizes or diameters, the larger designated as 41 and the smaller as 42. To sense this plurality of sizes of the balls 41 and 42 or, more exactly, the difference in their sizes, the sensing arm 39, which projects rear- Wardly from the shifter plate 37 through the cage 27 through a radial slot 43 therein, presents or offers to the balls a pair or plurality of horizontally or longitudinally aligned and elongated pockets or sockets, both substantially centered laterally or radially on and extending axially of the raceway 32, one a side-opening front, outer or adjacent pocket 44 and the other an inner, rear or remote pocket 45 opening forwardly or outwardly onto the front pocket. The pockets 44 and 45 differ in their widths or lateral or radial dimensions, so that the outer pocket can receive or accommodate any of the balls 41 and 42, While only a smaller ball 42 can be received or accommodated in the inner pocket. Thus, when powered by Water pressure applied to it from the passage 15 in the body 11 through the port 31, the piston 35 is permitted by the sensing arm 39 either a longer or maximum or a shorter or minimum advance stroke, the former if a smaller ball 42 and the latter if a larger ball 41 at that time is presented to or confronts the arm.

The second element carried by the shifter plate 37, the advancing cam 40, also projects rearwardly from the shifter plate but only into and not through the raceway 32 through a slot 46 in the cover member 34. Extending or projecting horizontally, parallel to the stem 26 and normal to the cage 27, and entering the raceway 32 in advance of or below the sensing arm 39 and preferably at the immediately preceding ball station or position, the advancing cam 40 has a diagonal cam face 47 sloping outwardly toward or in the direction of the sensing arm 39 and centered laterally or radially on the raceway. Of substantially the width of a larger ball 41 in a direction circumferential of the raceway 32, the advancing cam 40 and its slot 46 preferably are radially or laterally narrowed to such an extent that none of the balls can pass through the slot when the cam is retracted therefrom. Since projected into the raceway 32, except when the piston 35 is powered, the advancing cam 40 normally will close and block entry of foreign matter through the slot 46 into the raceway.

The sensing arm 39 and advancing cam 40 act not only oppositely but alternately on the balls 41 and 42 in the cage 27, the sensing anm sensing a presented ball on an advance stroke of the piston 35, whenever water pressure is applied to the sprinkler 7, and the advancing cam advancing the ball presented to it in the succeeding return stroke of the piston after the pressure has been cut ofi. Due to the vertical disposition of the cage 27 and raceway 32, the balls 41 and 42 will feed or be forced by gravity to the cam station in the direction which they are advanced by the advancing cam 40, so long as the weight of the balls on the feed or return side of the vertical centerline of the raceway at least equals that of any on the opposite, sensing or advancing side up through the cam station, the need for any greater weight being eliminated by a spring-pressed, roun'dnosed, holding or supporting pin 48 mounted on the side or peripheral wall 49 of the cage 27 and projecting substantially radially theret'hrough for normally supporting both the ball in the sensing station and those thereab ove on the sensing side of the raceways vertical centerline. Given a sufficient number of balls 41 and 42 in the cage 27 to cause them in succession to be lifted to the top of the raceway 32 by the force applied by the cam 40 and be fed by gravity to the cam station, the sequences in which the piston 35 will have the longer or maximum advance stroke will be determined by the number of smaller balls, their order or sequence. in the series of balls and the position of each relative to the sensing station at the start of a cycle of the sprinkler system 1.

The difierence in the lengths of the advance stroke of the piston 35 obtained by incrementally moving or advancing the balls 41 and 42 in the raceway 32 so as to confront or present the sensing arm 39, at on intervals of predetermined sequence in the operation of the system 1, with smaller, irregular, special or sprinkling balls or opening sensed elements 42, is applied through valving to open the nozzle 12 for sprinkling at the same intervals. While the longer or maximum stroke might be used to open a port or trip a switch for opening the nozzle 12 by fluid pressure or electrically actuated valving, it is preferred, for both simplicity and positive action, to open the nozzle mechanically by a direct mechanical connection or linkage to the piston. The preferred nozzle or sprinkler valve 14, accordingly, is a slide gate or gate valve 49 mounted for sliding normal or radial to the nozzle 12 across the latters front or outer end 50.

The slide or gate valve 14 conveniently is slideably mounted on a mounting bracket 51 fixed to or rigid or integral with the body arm 18 in a guideor slide-way 52 at a side of the nozzle 12. The same bracket 51, which for the purpose projects from the same side of the body 11 as the programming mechanism 13, also mounts a first class lever or lever arm 53 pivoted or fulcrumed intermediate its ends on the bracket and end or pin-andslot connected at its opposite ends respectively to the gate valve 49 and the shifter plate 37 fixed to the piston rod 36. A return spring 54, suitably in the form of a tensionspring anchored to and acting between the body 11 and the lever 53 on the piston side of the latters fulcrum 55, powers the retract stroke of the piston 35 and normally holds it in retracted position.

At all times engaging the front end- SE) of the nozzle 12 and shifting thereacross on each advance stroke of the piston 35, the gate valve 14 covers and closes the nozzles central bore or outlet 56 except on maximum shift under the longer stroke of the piston, when the nozzle is opened by alignment with its bore of an aperture 57 in the gate valve. The preferred position of the gate valve 14 at the end of the nozzle 12, ensures against entry of insects or other foreign matter into the bore 56 during the periods which the sprinkler is not sprinkling and an O-ring 58, seated in the front end of the nozzle about the bore and wiping against the gate valve, provides a fluid-type closure or seal for blocking flow or leakage from the bore except when it is aligned with the aperture 57.

The ability of the improved sequencing sprinkler 7 to be exposed to water pressure from the source on each on interval of the main control valve 9 but to respond to sprinkle only sequentially after a predetermined number or at the end of a predetermined sequence of such exposures, not only enables the sprinklers in each lateral line 6 to sprinkle at different intervals without regard to their relative positions in the line but, by permitting the sprinklers in the line to be connected in parallel rather than in series, frees them of dependence for operation upon the operability of every preceding sprinkler, thus precluding the failure of one sprinkler from cutting out or rendering inoperative part or all of its lateral line.

In the usual sprinkler installation, it is desirable that each sprinkler 7 in a lateral line 6 operate in turn in a full cycle of the system in which all operate. This is readily accomplishable in the preferred sprinkler 7 in which the incrementally rotating sensed means are the balls 41 and 42, by equating the total number of the larger, regular or non-sprinkling balls or non-opening sensed elements 41 and smaller, irregular, special or sprinkling balls or opening sensed elements 42 to the number of sprinklers in each lateral line 6 or a multiple thereof and including either one or, if a multiple, that multiple number of equally spaced smaller balls. Thus, for the illustrated s rinkler system 1 having nine sprinklers 7 in each lateral line 6, the programming mechanism. 13 should be assembled, as is the illustrated embodiment, with nine balls, eight larger and one smaller. If merely so assembled and installed in the lateral lines without being set or programmed, each sprinkler will only sprinkle every ninth on interval of the control valve 9 but only by happenstance will the sprinkling in each line be sequential. However, the sprinklers in a given lateral line can readily be set to sprinkle sequentially in any desired sequence simply by actuating the programming mechanism 13 of each manually, as by pressing against the outer end of the gate valve 49 or lever 53 to move their smaller balls 42 to different positions relative to the sensing position so that each will thereafter sprinkle at a different on interval.

From the above detailed description it will be apparent that there has been provided an improved pressure responsive sequencing sprinkler which is operable independently of other sprinklers in a sprinkler installation and enables the sprinklers in the installation to be adapted to sprinkle in any desired sequence. It should be understood that the described and disclosed embodiment is merely exemplary of the invention and that all modifica tions are intended to be included that do not depart from the spirit of the invention and the scope of the appende claims.

Having described my invention, I claim:

1. In a sprinkler system havingtimed on and off inter vals, a programmable pressure responsive sequencing valve comprising a body mountable on a line of said system, nozzle means mounted on said body, pressure responsive sensing means in said body and on said mounting thereof exposed to 'water pressure in said line on each on interval of said system, valve means normally closing and operable by said sensing means for opening said nozzle means, a plurality of opening and non-opening sensed elements selectively assemblable in any of a plu rality of series on said body, and means for causing said sensing means sequentially to sense the sensed elements of the selected series and only on sensing of an opening element operate on said valve means and automatically open said nozzle means during an on interval of said system.

2. A sprinkler according to claim 1 wherein the sprinkler is one of a plurality of like sprinklers mounted in spaced relation along a water line and the sensed elements of each sprinkler are selectively assemblable in situ to cause the sprinklers in said line to sprinkle automatically at different on intervals of the system in any desired sequence.

3. A sprinkler according to claim 2 wherein the sensed elements are movable and arranged in series, and the sensing means sense the elements in succession and after sensing an element move the succeeding element tiIltO position for sensing on the next on interval of the system.

4. A sprinkler according to claim 3 wherein the sensed elements are larger and smaller balls contained in a raceway in a cage, the sensing means are shiftable axially of the raceway in response to water pressure in the line,

and the sensing means include a sensing arm extending into said raceway for sensing the difference in the sizes of said balls and permitting maximum shifting of said sensing means only when a smaller ball is in sensing position.

5. A sprinkler according to claim 4 wherein the sensing means include an advancing cam and a piston shiftable axially of the raceway in a cylinder open at its inner end through a passage in the body to line pressure, said piston has a rod extending centrally through the cage and carries therebeyond means mounting the sensing arm and said advancing cam, and said advancing cam is projectable axially into the raceway in a position in advance of the sensing position for advancing a succeeding ball thereto.

6. A sprinkler according to claim 5, wherein the sensing arm and advancing cam act oppositely and alternately on the balls.

7. A sprinkler according to claim 6, including yieldable means projecting into the raceway between the positions therein of the advancing cam and sensing arm for supporting a ball in sensing position.

8. A sprinkler according to claim 7, wherein the cage and raceway are vertically disposed and the balls are gravity fed to position to be advanced by the advancing cam.

9. A sprinkler according to claim 5, wherein the nozzle means is a nozzle, the valve means is a gate valve slideable across an outer end of the nozzle, a lever fulcrurned on the body operatively connects the slide gate and the piston, and the slide gate has an aperture aligning with a bore of the nozzle on maximum shifting of the piston for opening the nozzle and enabling the sprinkler to sprinkle on said shifting.

10. A sprinkler according to claim 9, including spring means acting between the lever and the body for powering the return stroke of and normally holding the piston in retracted position.

11. A sprinkler according to claim 9, including an O-ring inset in the end of the nozzle and wiping against the gate valve for sealing the bore except on alignment thereof with the aperture in the valve.

12. A sprinkler according to claim 11, wherein the slide gate and lever are mounted on a bracket fixed to the body, the lever is a first-class lever, and Spring means acting between the body and the lever power the retract stroke of and normally hold the piston in retracted position. I

13. A sprinkler according to claim 12, wherein the body has an upright main part carrying below the programming mechanisma swivel coupling for mounting the sprinkler for rotation about a vertical axis on a riser of the line, the body has an arm projecting upward at an oblique angle to the main part and mounting the nozzle, and a flapper rotatably mounted on a post upstanding from the main part and swingable away from the arm under force of a jet from the nozzle and back against a stop thereon by spring means produces incremental rotation of the sprinkler while sprinkling.

14. In a system having a line to which fluid pressure is supplied at on intervals, a programmable sequencing valve comprising a body connectable to said line and having an outlet, pressure responsive sensing means in said body and on said connection thereof exposed to pressure in said line on each on interval thereof, valve means normally closing and operable by said sensing rneans for opening said outlet, a plurality of opening and non-opening sensed elements selectively assemblable in any of a plurality of series on said body, and means for causing said sensing [means on said on intervals sequentially to sense the sensed elements of the selected series and only on sensing of an opening element operate said valve means to open said outlet.

References Cited UNITED STATES PATENTS 1,979,477 11/1934 Leland 239--66 X 2,256,737 9/1941 Englehart 239-230 2,720,420 10/ 1955 Seiiferle 23957O X 2,793,908 5/1957 Carver 239-66 2,921,629 1/1960 Stout 23966 X 3,145,736 8/1964 Gheen 239-66 X 3,147,770 9/1964 Perlis 239-66 X M. HENSON WOOD, JR., Primary Examiner.

V. C. WILKS, Assistant Examiner.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1979477 *May 23, 1932Nov 6, 1934Leland Electric CoSprinkling system
US2256737 *Jul 14, 1937Sep 23, 1941Orton H EnglehartAutomatic reversing rotary sprinkler
US2720420 *Mar 15, 1954Oct 11, 1955Seifferle OliverSelf-flushing and pressure regulating fitting for irrigation sprinkler
US2793908 *Mar 30, 1956May 28, 1957R H Pierce Mfg CompanyRemote control irrigation system and valve
US2921629 *Sep 2, 1958Jan 19, 1960William H StoutControl device for sprinkler valves
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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3472265 *Feb 1, 1968Oct 14, 1969Davis Flow Valve IncSequential distributing valve
US3930618 *Mar 19, 1975Jan 6, 1976George LockwoodBalanced sprinkler impact drive
US4342424 *Nov 3, 1980Aug 3, 1982Nelson Irrigation CorporationCombined rotary impulse sprinkler head and shut-off valve
US4577802 *Aug 6, 1985Mar 25, 1986Utah State University FoundationMethod and system for furrow irrigation
US4673128 *Dec 17, 1985Jun 16, 1987Utah State University FoundationMethod and system for furrow irrigation
US6622933 *May 14, 2001Sep 23, 2003George A. YoungPressure sequence controlled valve and sprinkler system using same
US8230871Feb 11, 2008Jul 31, 2012Hurst James WFluid activated flow control system
US9341281Feb 5, 2013May 17, 2016Colt Irrigation LlcFluid activated flow control apparatus
US9599286Jan 16, 2015Mar 21, 2017Colt Irrigation, LLCFluid activated flow control apparatus
Classifications
U.S. Classification239/66, 239/262, 239/230, 239/70, 239/570, 137/624.13, 137/624.18
International ClassificationA01G25/16
Cooperative ClassificationA01G25/162
European ClassificationA01G25/16B