A fluid emitter of the kind used in irrigation provides a small controlled flow of fluid from a conduit and has a snap-on connection for quickly connecting the emitter to the conduit. The emitter is disposed underground with just an upper tip of the emitter extending above the surface. An end cap fits over this tip and can serve as a dust cap, a plug cap or a 90° elbow, a tee or a cross connection for an extension hose.
Application Number:
05/376550
Publication Date:
04/23/1974
Other Classes:
239/542, 138/44, 239/272, 137/861, 239/590, 239/288.300, 285/197
International Classes:
A01G25/02; B05B1/34; B05B1/20
Field of Search:
239/66,76,104,207,201,266,267,271,272,288,288.3,288.5,542,590 137/608 138/42-46
US Patent References:
| 3752505 | SPIGOT MEMBER FOR BELL AND SPIGOT JOINT IN IRRIGATION PIPE | August 1973 | Stout | |
Primary Examiner:
Ward Jr., Robert S.
Attorney, Agent or Firm:
Owen, Wickersham & Erickson
Claims:
I claim
1. A flow restricting fluid emitter of the kind used in irrigation, said emitter comprising, an outer tubular sleeve member, an inner spool member extending axially within the outer member, flow restricting means providing a flow restricting passageway for fluid flow between the outer and inner members, an inlet for the passageway adjacent one end of the inner member, an outlet for the passageway extending through the outer member, and snap-on means for connecting said inlet with the interior of a fluid conduit.
2. The invention defined in claim 1 wherein the emitter is connected to the fluid conduit with the axes of the inner and outer members disposed vertically.
3. The invention defined in claim 2 including a vertically extending extention connected with the outer tubular sleeve member and having an opening at its upper end whereby the emitter and associated conduit can be buried underground with just an upper tip of the extention and said opening extending above the ground surface.
4. The invention defined in claim 2 wherein the spool is a hollow tubular member having a large diameter internal bore and including an end wall closing the bore at the end opposite said inlet.
5. The invention defined in claim 4 including flow reversal means associated with the said inlet for preventing the entrance of suspended foreign matter from the fluid in the bore to the fluid in said flow restricting passageway.
6. The invention defined in claim 3 including an end cap for the tip extending above ground.
7. The invention defined in claim 6 wherein the end cap is a dust cover for preventing the entrance of dust and dirt into said opening.
8. The invention defined in claim 6 wherein the end cap is a plug for closing said opening.
9. The invention defined in claim 6 wherein the end cap has a sidewall and a second opening in said sidewall for connection to an extention hose.
10. The invention defined in claim 6 wherein the end cap has a cross providing a plurality of outlets.
11. The invention defined in claim 1 wherein the snap-on means include flexible gripper flanges connected integrally to the outer tubular sleeve member for snapping around and resiliently onto the outside of said fluid conduit.
12. The invention defined in claim 11 wherein the snap-on means include a hollow center stem adapted to fit through a perforation in said fluid conduit.
13. The invention defined in claim 12 wherein the center stem includes a barb on an outside surface for retaining the center stem in the perforation in the conduit.
14. The invention defined in claim 1 wherein the outer and inner tubular members are conically tapered and axially movable relative to one another to a limited extent to increase the radial space between the tubular members for flushing said flow restricting passageway.
Description:
BACKGROUND OF THE INVENTION
This invention relates to an irrigation system in which water or another fluid is discharged at low rates and in a plurality of fixed locations. It relates particularly to a fluid emitter which is adapted to be positioned under ground with just the upper tip of the emitter extending above the surface.
This invention is an improvement on the flow restricter with flushing disclosed in my U.S. Pat. No. 3,693,657 issued Sept. 26, 1972.
In irrigation systems of the kind to which this invention relates the fluid is conducted through closed pipes. The fluid emitters of the present invention are connected to the pipes at spaced locations to provide a slow, restricted or drip flow of fluid to the area to be irrigated.
In many instances it is desirable to place the conduit and the main part of the emitter underground. However, in such cases a tip of the emitter with the outlet opening is positioned above the surface so that there is no resistance to flow through the outlet opening. This is necessary to insure that the rate of flow through the emitter is controlled by the size and length of the flow restricting passageway without any interference to flow through the outlet.
One of the problems of locating just a tip of the emitter above the surface is the relative ease with which stirred-up dirt or dust or other material can enter the outlet opening and pass into the interior of the emitter. Once any such clogging material gets inside the emitter, it can work its way into the very small diameter flow restricting passageway. This can cause clogging or partial clogging of the passageway so as to interfere with the desired rate of flow through the emitter.
It is an object of the present invention to construct a dust cap for the part of the emitter which projects above the surface to prevent the entry of dust into the interior of the emitter. It is a related object to construct the emitter so that the dust cover can be replaced by an end plug or by an elbow tee or cross connection which permits an extension hose to be connected to the emitter.
A normal field installation will require a large number of fluid emitters to be assembled with related conduits. The normal prior art technique for assembling such irrigation systems involved cutting entirely through the conduit and then inserting two end extensions of the emitter into related ends of the conduit. This method of assembly required a number of hand operations and also was time consuming.
It is another object of the present invention to construct an emitter so that the emitter can be snapped on to a conduit by means of a snap-on connection which greatly simplifies assembly.
SUMMARY OF THE INVENTION
The fluid emitter of the present invention incorporates a snap-on connection which permits the fluid emitter to be snapped on to the outside of a conduit. A small hole is drilled or punched through the conduit wall and a barbed hollow stem of the emitter is pressed through the opening. The barb on the stem engages the inside of the conduit to prevent pulling out of the stem once it has been pressed through the opening. A pair of flexible curved flanges are formed on the emitter. The flanges snap over the outside of the conduit and grip the outside of the conduit to hold the emitter in place.
The emitter comprises an outer tubular sleeve member and an inner spool. In a specific form of the present invention, a helically extending thread between the sleeve and spool provides a long, narrow flow restricting passageway.
A hollow cylindrical extension is formed integrally with the upper end of the outer tubular member for positioning a tip of the emitter and an outlet opening above the ground surface. An end cap is associated with the tip. The end cap can be a dust cover to prevent dust and dirt from getting into the outlet opening, an end plug to close off the opening entirely or an elbow, a tee or a cross connection for an extension hose.
Fluid emitter apparatus and methods which incorporate the structure and techniques described above and which are effective to function as described above constitute specific objects of this invention.
Other objects, advantages and features of my invention will become apparent from the following detailed description taken with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of a fluid emitter constructed in accordance with one embodiment of the present invention;
FIG. 2 is an elevation view in cross-section taken along the line and in the direction indicated by the arrows 2--2 in FIG. 1;
FIG. 3 is a plan view taken along the line and in the direction indicated by the arrows 3--3 in FIG. 2;
FIG. 4 is an end elevation view of a fluid emitter like that shown in FIGS. 1 and 2 but having an extention hose for permitting the emitter of the FIG. 4 form to be buried deeper beneath the surface;
FIG. 5 is an isometric view of an end cap having a two-outlet cross;
FIG. 6 is an isometric view of an end cap having a four-outlet cross;
FIG. 7 is a fragmentary end elevation view showing the FIG. 5 cap on the emitter; and
FIG. 8 is an end elevation view showing the FIG. 6 end cap on the emitter.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A fluid emitter constructed in accordance with one embodiment of the present invention is indicated generally by the reference numeral 10 in FIGS. 1 and 2. In FIG. 1 the emitter 10 is shown connected to a conduit 12. In a typical irrigation system a number of emitters 10 are connected to the conduit 12 as desired locations along the conduit.
As best shown in the cross-section view of FIG. 2, the emitter 10 comprises an outer tubular sleeve member 14 and an inner tubular spool 16. Both members may preferably have a slight conical taper as illustrated. In a specific embodiment of the present invention this taper is at an angle of 4 degrees from the longitudinal axis.
The outer surface of the spool 16 is formed with a helically extending thread 18. When the parts are disposed as illustrated in FIG. 2 (with the outer surface of the thread engaged with the inner surface of the sleeve 14), the thread 18 provides a corresponding helically extending flow passageway 20 of extended length and restricted cross-sectional area.
Water or other fluid flows into the passageway 20 from the inner bore 22 of the conduit 12 through an axially extending passageway 24 in a stem 26. The fluid from the passageway 26 enters into the central part of the emitter 10 formed by the bore 28 in the spool 16. An end wall 38 at the upper end of the spool 16 closes off that end of the spool. To get into the flow restricting passageway 20 the fluid within the bore 28 must flow up and over the upper edge 30 of an axially extending flange 32 and then downward through a narrow annular channel 34 and then upward again into the inlet end 36 of the spiral flow restricting passageway 20.
The fluid flowing out the outlet end 40 of the flow restricting passageway 20 flows into a large diameter bore 42 of an upwardly extending end extention 44 formed integrally with the sleeve 14.
The upper end or tip 50 of the extention 44 has an outlet opening 46.
As illustrated by the lines marked with the legend "Ground Level" in FIGS. 1 and 2, just the upper tip 50 of the extention 44 extends above the surface of the ground. The rest of the fluid emitter 10 and the conduit 12 are buried underground.
An end cap 52 is associated with the tip 50. The end cap 52 can be constructed to perform several functions. As illustrated in FIG. 2, the end cap 52 is slightly larger in internal diameter than the outside diameter of the tip 50 so as to provide a narrow annular channel 54 for the flow of fluid out of the emitter 10. In this case, the cap 52 serves as a dust cap and preferably includes a bar 56 which spans the diameter of the opening 46 and rests on the upper edges of the tip 50 to hold the dust cap in place as illustrated in FIG. 2. This dust cap effectively prevents dirt and dust from getting into the opening 46 and clogging the flow restricting passageway 20.
The end cap 52 can also be constructed to close off or plug the opening 46.
The end cap 52 can also be constructed to serve as an elbow. In this case the lower edge of the end cap engages the outside surface of the tip 50 in fluid sealing relation and the sidewall has an opening 58 for an extention hose. (see FIG. 1).
Other end cap constructions are shown in FIGS. 5-8. FIGS. 5 and 7 show an end cap having a tee or cross 60 providing two outlets 62 for extention hoses.
FIGS. 6 and 8 show an end cap having a cross 64 having four outlets 66.
In some cases it may be desirable to place the emitter a considerable distance below the ground surface. For example, it may be desirable to place the emitter and conduit 12 as much as 36 inches below the ground surface.
The emitter shown in FIG. 4 is constructed to permit a variable length extention hose 70 to be connected to the emitter so that the emitter can readily be located at any desired depth. In the FIG. 4 embodiment the outside tubular member 14 is formed with a hose fitting 72 rather than the fixed extention 44 of the FIG. 2 embodiment. The hose 70 is then connected to the fitting 72, cut to the desired length, and the cap 52 is placed in position.
As noted above the outer sleeve 14 and the inner spool 16 each has a slight conical configuration. The spool 16 is axially movable to a limited extent within the outer sleeve to permit flushing of the passageway 20 in the event some clogging material does get into this passageway. Thus, after removing the end caps, the spool 16 can be pushed downwardly, as viewed in FIG. 2, by a rod or the like, to increase the space between the sleeve and the spool for flushing. It is then returned to the position illustrated in FIG. 2 by hydraulic pressure for normal regulation of the output from the emitter.
The overlap between the upper end of the circular flange 32 and the lower end of the spool 16 provides the flow reversal described above which helps prevent the entrance of clogging materials into the flow restricting passageway 20.
As best illustrated in FIG. 3 the outer surface of the flange 32 is preferably formed with a series of circumferentially spaced and radially projecting ribs 33. These ribs help to maintain alignment of the spool 16 when it is moved downwardly for flushing as described above.
The fluid emitter 10 includes a snap-on connection for facilitating assembly of the emitter with the conduit 12. As best illustrated in the cross-section view of FIG. 2, the snap-on connection includes a pair of flexible curved flanges 60 which spring apart sufficiently far to permit the lower ends 62 of the flanges to pass over and around the outside diameter of the conduit 12. The flanges 60 then spring back and resiliently grip the outside of the conduit to hold the fluid emitter in place.
The stem 26 has a barb 64 formed at its lower end. This barb is pressed through a perforation which is drilled or otherwise formed in the conduit 12, and the barb then prevents retraction of the stem.
In a specific form of the present invention the parts of the fluid emitter 10 are molded from polypropylene.
The present invention thus provides a quite inexpensive fluid emitter construction which has proven highly effective for the flow regulation desired, and the fluid emitter can be very quickly assembled with the main conduit line by the snap-on connection described above.
To those skilled in the art to which this invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the spirit and scope of the invention. The disclosures and the description herein are purely illustrative and are not intended to be in any sense limiting.