WO2019064246A1

WO2019064246A1 - Irrigation device

Info

Publication number: WO2019064246A1
Application number: PCT/IB2018/057533
Authority: WO
Inventors: Johannes Hiemstra; Christoffel Theron
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-09-29
Filing date: 2018-09-28
Publication date: 2019-04-04
Anticipated expiration: 2020-03-29

Abstract

This invention relates to an irrigation device that includes an emitter tube, an inner body defining an internal passage therethrough within which the emitter tube is located, and an outer body defining a cavity within which the inner body is located. The arrangement of the emitter tube, inner body and outer body being such that liquid entering the irrigation device through an outer body inlet end, subsequently flows through the inner body and emitter tube and is discharged from the irrigation device through an outlet of the emitter tube, wherein hydraulic pressure inside the cavity and passage causes the inner body and emitter tube to be displaced upwardly, and wherein hydraulic forces exerted by the flowing liquid on the emitter tube causes the outlet end of the emitter tube to continuously move about.

Description

IRRIGATION DEVICE

FIELD OF THE INVENTION This invention relates to an irrigation device. More particularly, but not exclusively, this invention relates to an irrigation device which could be sunk into the ground.

BACKGROUND TO THE INVENTION Irrigation devices are well known in the art which include an emitter tube of resiliently flexible material having a mounted base inlet end and an unmounted free outlet end wherein liquid flowing at a sufficient rate through the emitter tube exerts hydraulic forces on the tube that causes the outlet end continuously to move about. The stream of ejecting liquid is broken up into droplets which are deposited substantially uniformly over a circular area on the ground around the irrigation device.

Due to the fact that no mist is formed during the operation of such irrigation devices, they are extremely water efficient when compared to other conventional irrigation devices.

Currently, irrigation devices of the type described above are mainly being used in the agricultural sector, where they are secured to overhead support structures.

A disadvantage associated with these irrigation devices is that the efficacy of the emitter tube is adversely affected by contact with unwanted articles, such as dirt, plant material and the like, which causes the tube to move erratically, resulting in an uneven distribution of droplets on the ground.

When known configurations of these irrigation devices are sunk into the ground, it is easy for adjacent plant material and dirt to interfere with the movement of the emitter tube as its base end is substantially in line with the ground.

OBJECT OF THE INVENTION It is accordingly an object of the present invention to provide an irrigation device with which the above disadvantage could be overcome, or at least reduced, and/or that would be a useful alternative to known irrigation devices.

SUMMARY OF THE INVENTION

According to the invention, there is provided an irrigation device comprising:

- an emitter tube being of resiliently flexible material including a tube inlet end and an opposing free tube outlet end;

- an inner body defining an internal longitudinal passage therethrough leading from an inner body inlet end to an opposing inner body outlet end, the emitter tube being located inside the passage; and

- an outer body defining an internal longitudinal cavity therethrough leading from an outer body inlet end to an opposing outer body outlet end, the inner body being located inside the cavity, the arrangement being such that liquid entering the irrigation device through the outer body inlet end, subsequently flows through the inner body and emitter tube and is discharged from the irrigation device through the tube outlet end, wherein hydraulic pressure inside the cavity causes the inner body to be displaced upwardly relative to the outer body and hydraulic pressure inside the passage causes the emitter tube to be displaced upwardly relative to the inner body, and wherein hydraulic forces exerted by the flowing liquid on the emitter tube cause the tube outlet end to continuously move about. There is provided for the emitter tube, inner body and outer body to be telescopically displaceable relative to each other.

According to an example embodiment of the invention, the inner body inlet end defines a socket and the irrigation device further includes flow regulating means being securable to the socket.

The flow regulating means may include a filter member and a flow regulating element being locatable in the filter member, whereby with the filter member secured to the socket, the flow regulating element is clamped against the inner body by the filter member.

The inner and outer bodies may be of rigid material. The irrigation device may further include an end cover that is securable to the outer body outlet end, the end cover including an opening through which the inner body extends when being subjected to the hydraulic pressure. The irrigation device may include a first biasing means which serves to bias the emitter tube downwardly towards a retracted position within the inner body.

Further, the irrigation device may include a second biasing means which serves to bias the inner body downwardly towards a retracted position within the outer body.

The biasing means may take the form of a compression coil spring.

These and other features of the invention are described in more detail below.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

One embodiment of the invention is described below, by way of a non-limiting example only and with reference to the accompanying drawings in which:

Figure 1 is a schematic perspective view of an irrigation device in a retracted configuration, in accordance with the invention;

Figure 2 is a schematic section view of the irrigation device of figure 1 ;

Figure 3 is a schematic perspective view of the irrigation device of figure 1 in a deployed configuration; and Figure 4 is a schematic section view of the irrigation device of figure 3.

DETAILED DESCRIPTION OF THE INVENTION Referring to the figures, an irrigation device in accordance with the invention is generally designated by reference numeral 10.

The device 10 comprises an emitter tube 12, an open-ended inner body 14 for receiving the emitter tube 1 2, and an open-ended outer body 16 for receiving the inner body 14 and thus also the emitter tube 1 2.

The emitter tube 1 2 is of resiliently flexible, elastomeric material and includes a tube inlet end 18 and an opposing free tube outlet end 20. The inner body 14 is of rigid material and defines an internal longitudinal passage 22 therethrough leading from an inner body inlet end 24 to an opposing inner body outlet end 26. The outer body 16 is of rigid material and defines an internal longitudinal cavity 28 therethrough leading from an outer body inlet end 30 to an opposing outer body outlet end 32. The respective inlet ends 1 8, 24, and 30 are located at operatively upper ends of their respective associated components, and the respective outlet ends 20, 26, and 32 are located at operatively lower ends of their respective associated components.

In the region of the tube inlet end 1 8, the emitter tube 12 defines an external tube shoulder 34. The tube 12 is mounted onto a fitting 36 that includes a bore or passageway 38 that is aligned with the emitter tube 12. The passageway 38 leads from the operatively lower end of the fitting 36 into the emitter tube 12. As illustrated, the tube 1 2 is located, at least partially, in the passage 22 and telescopically displaceable along the passage 22 and relative to the inner body 14.

The inner body 14 includes, at its outlet end 26, an inwardly protruding annular flange 42 that is dimensioned so to engage the external tube shoulder 34 to thereby prevent the entire tube 12 from exiting the passage 22 through the inner tube outlet end 26. At its inlet end 24, the inner body 14 includes an internally threaded socket 44 for receiving flow regulating means 46. As illustrated, the inner body 14 is located, at least partially, in the cavity 28 and telescopically displaceable along the cavity 28 and relative to the outer body 1 6. In the passage 22, between the flange 42 and a skirt of the fitting 36, there is provided an inner compression coil spring 47, which serves to bias the tube 12 downwardly to its retracted position (as shown in figure 2).

The flow regulating means 46 includes a flow regulating element 48 and a filter member 50. The flow regulating element 48 includes a pair of axially aligned recesses 52.1 and 52.2 and a series of flow channels 54.1 , 54.2 and 54.3 respectively leading from the operatively bottom-end of the element 48 to the recess 52.1 , from the recess 52.1 to the recess 52.2, and from the recess 52.2 to the operatively upper-end of the element 48. Corresponding recesses 52 and channels 54 are defined in opposing sides of the element 48. A cylinder 56 of elastomeric material fits over the element 48, being stretched across the recesses 52.1 and 52.2 and channels 54.1 and 54.2 to form them into flow chambers. Essentially, the effect of the element 48 is to maintain the flow rate of liquid through the emitter tube 12 substantially constant, irrespective of fluctuations in the supply of liquid to the device 10. The filter member 50 includes an upper externally threaded part 58 for engaging the socket 44, an intermediate cylindrically-shaped sieve 60, and lower circular base 62. With the filter member 50 secured to the socket 44, and the element 48 located inside it, the filter member 50 clamps the element 48 against the inner body 14.

The outer body 16 includes, at its inlet end 30, a first externally threaded section 64 for receiving an irrigation supply-pipe (not shown). At its opposing outlet end 32, a second externally threaded section 66 is provided for receiving an end cap or cover 68 over it. The cover 68 includes an opening 70 in its centre through which the inner body 14 extends when being subjected to the hydraulic pressure, in use, and an internally threaded section 72 that screws over the threaded section 66 of the outer body 16.

A lip seal 74 extends about the inner body 14, adjacent to the cover 68 and outer body 16, as shown. The lip seal 74 urges against the inner body 14, cover 68 and outer body 1 6, especially when subjected to hydraulic pressure from the cavity 28, so to prevent liquid from leaking from the cavity 28 between the outer body 1 6, cover 68, and inner body 14. It will be appreciated that, due to the fact that the emitter tube 1 2 is of elastomeric material, a seal is formed between the emitter tube 1 2 and inner body 14 when the emitter tube 12 is seated against the inner body 14 when it is in its extended position, as shown in figure 4.

In the cavity 28, between the inner lip seal 74 and the socket 44, there is provided an outer compression coil spring 78, which serves to bias the inner body 14 downwardly to its retracted position. The outer body 16 includes a plurality of radially spaced ribs 80, spanning substantially its length, to provide grip to a user when securing or loosening the cover 72 from the outer body 1 6. Furthermore, the ribs 80 restrict rotation of the device 10 when secured in the ground.

An O-ring seal 82 is provided at the outer body inlet end 30 of the outer body 1 6 that seals against the base 62 in order to prevent liquid from leaking from the cavity 28 between the outer body 16 and filter member 50. Liquid is thus retained in the device 10 when installed but not in use.

In use, the device 1 0 will be sunk into the ground so that the cap 68 is generally flush with the ground surface (not shown). When the liquid supply to the device 1 0 is shut off, the bias provided by the inner and outer springs (47, 78) will ensure that the device 10 is in its retracted condition, whereby the emitter tube 12 is retracted into the inner body 14 and the inner body 14 is retracted into the outer body 16, as shown in figures 1 and 2.

When the liquid supply is turned on, liquid will enter the device 10 through the inlet end 30 and from there flow, via the cavity 28 and through the sieve 60 into the flow regulation element 48. Upon entering the element 48, the liquid will flow via the channel 54.1 , recess 52.1 , channel 54.2, recess 52.2 and channel 54.3 into the inner body 14. From there it will flow via the passageway 38 into the emitter tube 12. It then flows along the tube 12 and is discharged from it via its outlet end 20. With a sufficient flow rate through the emitter tube 18, hydraulic forces exerted by the flowing liquid on the tube 12 cause the outlet end 20 continuously to move about (indicated in broken lines on figure 3). This in turn causes the flow stream issuing from the outlet end 20 to be broken up into droplets which are spread over a circular area on the ground around the device 10.

Furthermore, hydraulic pressure inside the cavity 28 below the flow regulating means 46 displaces the flow regulating means 46 and thus the inner body 14 upwardly, relative to the outer body 1 6, against predominantly the bias of the outer spring 78, thus extending the inner body 14 from the cavity 28 via the opening 70. Similarly, the hydraulic pressure inside the passage 22 below the fitting 36 displaces the fitting 36 and thus the emitter tube 1 2 upwardly, relative to the inner body 14, against predominantly the bias of the inner spring 47 and weight of the sleeve 40, thus extending the emitter tube 12 from the passage 22 between the flange 42.

Irrigating large gardens, public parks, golf courses, sports stadia, and the like requires large amounts of water. Irrigation devices currently being used for these applications generate a significant amount of mist which increases water evaporation, making them water inefficient. Furthermore, such irrigation devices generally include complex gearboxes, rotation mechanisms and splash plates. These moving parts require regular maintenance which is expensive. Also, irrigation devices of this kind require a high-pressure water supply, of in the order of 4.5 - 8 Bar, which is expensive to generate and maintain. It will be appreciated that when the irrigation device 1 0 is sunk into the ground, the entire tube 12 will stand proud of the ground making it significantly more difficult for adjacent plant material and dirt to interfere with the movement of the emitter tube 12. Also, the device 10 has very few moving components, is inexpensive to replace and maintain, and can effectively operate on a water supply pressure in the order of 2 Bar, making the device 10 very cost effective to operate.

It will be appreciated by those skilled in the art that the invention is not limited to the precise details as described herein and that many variations are possible without departing from the scope of the appended claims. As such, the present invention extends to all functionally equivalent structures, methods and uses that are within its scope.

The description is presented by way of example only in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention. The words which have been used herein are words of description and illustration, rather than words of limitation.

Claims

1 ) An irrigation device comprising:

an emitter tube being of resiliently flexible material including a tube inlet end and an opposing free tube outlet end;

an inner body defining an internal longitudinal passage therethrough leading from an inner body inlet end to an opposing inner body outlet end, the emitter tube being located inside the passage; and

an outer body defining an internal longitudinal cavity therethrough leading from an outer body inlet end to an opposing outer body outlet end, the inner body being located inside the cavity,

the arrangement being such that liquid entering the irrigation device through the outer body inlet end, subsequently flows through the inner body and emitter tube and is discharged from the irrigation device through the tube outlet end, wherein hydraulic pressure inside the cavity causes the inner body to be displaced upwardly relative to the outer body and hydraulic pressure inside the passage causes the emitter tube to be displaced upwardly relative to the inner body, and wherein hydraulic forces exerted by the flowing liquid on the emitter tube cause the tube outlet end to continuously move about.

2) The irrigation device of claim 1 , wherein the emitter tube, inner body and outer body are telescopically displaceable relative to each other. 3) The irrigation device of any one of the preceding claims, wherein the inner body inlet end defines a socket and the irrigation device further includes flow regulating means being securable to the socket. 4) The irrigation device of claim 3, wherein the flow regulating means include a filter member and a flow regulating element being locatable in the filter member, whereby with the filter member secured to the socket, the flow regulating element is clamped against the inner body by the filter member. 5) The irrigation device of any one of the preceding claims, wherein the inner and outer bodies are of rigid material.

6) The irrigation device of any one of the preceding claims including an end cover that is securable to the outer body outlet end, the end cover including an opening through which the inner body extends when being subjected to the hydraulic pressure.

7) The irrigation device of any one of the preceding claims including a first biasing means which serves to bias the emitter tube downwardly towards a retracted position within the inner body.

8) The irrigation device of any one of the preceding claims including a second biasing means which serves to bias the inner body downwardly towards a retracted position within the outer body. 9) The irrigation device of any of claim 7 or claim 8, wherein the biasing means is a compression coil spring.

The irrigation device of claim 1 , substantially as herein described with reference to the accompanying figures.