GB2620016A

GB2620016A - Irrigation system

Info

Publication number: GB2620016A
Application number: GB2306580.8A
Authority: GB
Inventors: Constable Jordan
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-05-04
Filing date: 2023-05-04
Publication date: 2023-12-27
Also published as: GB202206477D0; GB202306580D0

Abstract

A modular subsurface irrigation system comprises a plurality of interconnectable trays 10 each having a rigid peripheral open frame with upstanding sides 12a-d, a capillary mat 20 covering a lower end of the frame, at least one water conduit 14a-d connected between opposite sides of the frame, connection ports (24, fig 2) in the conduit for enabling fluid communication to be established between conduits of adjacent trays, and perforations or a permeable member to allow water to leak from the conduit onto the capillary mat. The conduit comprises two mating parts, a first part being formed integrally with the sides of the tray and being shaped as a channel open on its side facing the top or the bottom of the tray and a second part being a cover (22) that serves to close the channel so as to complete the conduit. One of the parts is porous, perforated, or fitted with porous members to allow a slow controlled leakage of the water from the conduit onto the capillary mat. The connection ports maybe upwardly facing female sockets for use with connectors 16 in the form of a short pipe with a U-bend. The trays maybe square.

Description

Irrigation System

Field of the invention

The invention relates to a subsurface irrigation system that is suitable for grass lawns and other outdoor applications.

Summary of the invention

According to the present invention, there is provided a modular subsurface irrigation system, comprising a plurality of inter-connectable trays each having a rigid peripheral open frame with upstanding sides, a capillary mat covering a lower end of the frame, at least one water conduit connected between opposite sides of the frame, connection ports in the conduit for enabling fluid communication to be established between conduits of adjacent trays, and perforations or a permeable member to allow water to leak from the conduit onto the capillary mat, wherein the conduit comprises two mating parts, a first part being formed integrally with the sides of the tray and being shaped as a channel open on its side facing the top or the bottom of the tray and a second part being a cover that serves to close the channel so as to complete the conduit, and wherein one of the parts is porous, perforated, or fitted with porous members to allow a slow controlled leakage of the water from the conduit onto the capillary mat.

The permeable member may be a membrane or a porous plug protruding from the underside of the conduit. -2 -

The trays of the irrigation system of the present invention may be laid in the same way as tiles and are shaped such that, when laid next to one another, they can cover the whole of an area to be irrigated. Most simply and practically, the trays may be square or rectangular, but they may alternatively have any other shape permitting full area coverage, such as hexagonal.

The trays are laid next to one another on the ground beneath the eventual level of the turf and connectors are used as the trays are being laid to establish fluid communication between the conduits of adjacent trays. In this way, connection of an end tray to a water supply suffices to supply water to all the other trays.

In use, after the trays have been laid on the ground next to one another and their conduits are interconnected, each tray is filled with soil. Water drips onto the mat at the bottom of each from the built-in conduit and by the capillary, or wicking, action of the mat, the water is distributed uniformly to all the soil filling the trays.

After the trays have been laid and filled with soil, as described above, a layer of topsoil is applied to cover the tops of the trays and grass or other plants with shallow roots may be grown on the topsoil. Alternatively, turf piece may be laid over the trays in the same way as over other prepared ground. In this way, the irrigation system lies below the lawn surface and serves to water the entire lawn evenly.

If desired, the water impermeable membrane may be provided below the capillary mat. Such a membrane may serve as a weed guard and also to -3 -remain the water discharged from the conduits and prevent from seeping into the ground beneath.

The combined depth of the soil in the trays and the topsoil may be around 12.5cms, this corresponding to the maximum depth to which the roots of the grass or other plants may penetrate. The capillary mat may serve to prevent the roots from growing down any further. On account of this, the surface onto which the trays are laid need not be specially prepared, other than being levelled to the desired height.

Preferred features In some embodiments, the trays are made of a plastics material that is not bio-degradable. High density polyethylene is well suited for this purpose 15 as it offers both the chemical stability and structural rigidity.

The sides and the first part of the conduit may be formed by injection moulding. The cover may be formed of the same material as the tray, or of a different plastics material, such as PTFE.

Small hole or perforations may be formed in the cover, or the first part of the conduit, to allow a slow controlled leakage of the water from the conduit onto the capillary mat. Alternatively, a permeable plastics member with a structure containing repeating pores may be employed.

The capillary mat may be made of a non-woven synthetic fleece material, such as PET (polyethylene terephthalate). The fleece material -4 -completely covers the 'lower' part of the tray including the channel, protecting it from the surrounding earth.

The connection ports may be upwardly facing female sockets for use 5 with connectors in the form of short pipe with a U-bend. The end of each limb of the connector may be designed to be inserted into the female socket of a respective one of two contiguous trays. A water-tight seal may be achieved by the use of 0-rings that are compressed between the connectors and the sockets. As well as acting to establish fluid communication between 10 the conduits of adjacent trays, the connectors may also serve as clips to hold the trays against one another.

The coimectors may be recessed into notches formed in the upper edges of the sides of the frame so as not to protrude above the upper end of 15 the frame.

It is desirable to form each tray with multiple conduits. In some embodiments, the tray is square and has two or more conduits extending parallel to one another between a first pair of opposite sides of the square and two or more further conduits extending parallel to one another between the other pair of sides at right angles to the first two conduits. At their intersections, the conduits preferably communicate with one another. If the trays have sides of, say 50cm s, the conduits will only be 25cm s apart therefore requiring the capillary web to transport water only come 12.5cms away from each conduit. Thus, by providing multiple conduits, it is possible to enable the size of the trays to be increased. -s -

If desired, each tray may comprise a data bus for enabling a moisture sensor fitted to the tray to communicate with a central computer.

Brief description of the drawings

The invention will now be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a plan view of two trays laid side by side, and Figure 2 is a section along the line 11-11 in Figure 1.

Detailed description of the drawings

Figure 1 shows two trays 10 arranged side by side. Each tray comprises a square open frame made up of four sides 12a, 12b, 12c and 12d each typically 50cms long and 10cms high. Each tray further comprises four conduits in fluid communication with one another. Though only four such conduits are shown in the illustrated embodiment, in practice there may be more, typically six. A first pair of conduits 14a and 14b extend parallel to one another between the side 12b and 12d of the frame and the second pair 14c and 14d extend at right angles to the first pair between the sides 12a and 12c of the frame In the illustrated embodiment, the upper sides of the conduits 14a-14d and the sides 12a-12d are formed as a single moulding of high-density polyethylene. The upper sides of the conduits 14a-14d are formed as downward facing channels which are sealed by a separate cover 22, shown in the cross section of Figure 2. it would be alternatively possible for the lower sides of the conduit to be formed integrally with the sides of the tray. -6 -

The covers 12 of all the channels are made as a one-piece cover moulding that incorporates a surrounding rim. In plan, the cover moulding resembles one of the frames 10 shown in Figure 1 but is essentially flat. The rim of the cover moulding fits within a recess in the lower edge of the sides 12a-12d of the frame of the tray, as shown in Figure 2. The recess also serves to retain a capillary mat 20.

The cover moulding is permanently secured in position so as to enclose the volumes defined by the conduits so as to create flow channels along 10 which water can flow.

The cover moulding is designed to allow water to escape from the flow channels defined by the conduits onto the capillary mat 20. The cover moulding, which may be made of PTFE, may for this purpose be regularly perforated or it may be made of a material having pores through which water can pass. In the illustrated embodiment, the cover moulding 22 is provided with plugs 26 of a porous plastics material that project downwards from the cover assembly and penetrate into the mat 20 to act as support feet for the cover assembly. The plugs 26 may be located at any point along the length of each cover but it is particularly desirable to provide one at each conduit intersection, so that the cover moulding may be supported on the ground evenly over its entire area.

Connection ports 18 in the form of upwardly facing female sockets are provided for enabling at least selected ones of the conduits 14a-14d to be connected into a water circuit. As shown in Figure 2, fluid communication can be established between conduits of adjacent trays by means of U-shaped connectors 16 that are sealingly received in the sockets 18 by means of 0-rings 24. Notches 28 are formed in the upper edges of the sides 12a-12d for receiving the connectors 16 so that they should not protrude above the upper edges of the trays 10.

The capillary mat 20, which may typically have a thickness of around 16mm, is secured in the recess in the lower edges of sides of the tray 10 to overlie the entire cover moulding. The mat, which may be of a non-woven fleece made of PET fibres, serves to spread the water escaping from the conduits 14a-14d laterally by capillary action to cover the entire area of the tray. In the covers are formed with perforations, the mat 20 prevents them from being blocked and it also acts to limit the root growth of the grass.

hi use, if the lawn to be laid is to be at the height of the existing ground level, then the ground is dug to a depth of about 15cms and levelled. Such digging is required to compensate for the depth of the irrigation system and the overlying layer of topsoil and turf Trays 10 are then laid on the ground in the same manner as tiles. Connectors 16 are inserted into some of the sockets 18 to establish fluid communication between the conduits of the adjacent trays and such sockets as are not used or required are capped off using suitable plugs. The trays are next filled with soil to the level of the upper edges of the sides of the trays and a further layer of topsoil is applied to bury the entire irrigation system. Grass is them grown from seed or laid as turf pieces.

Having in this way established a network of buried leaky conduits, it remains only to connect at least one of the end trays to a water supply. Such a supply may comprise a tank and a pump supplying water from the tank to be -8 -buried conduits. If desired, nutrients, fertilisers and/or weed killers may be mixed with water in the tank, as desired.

The water escaping from the covers 22 onto the capillary mat or fleece 5 20 is evenly distributed by the wicking action of the fleece over the entire area of each tray thus ensuring that the lawn is uniformly watered.

If desired, a data bus may be secured to a side of each tray, to which a moisture sensor mounted on the tray may be connected to send a signal to a computer to indicate the moisture lever within the tray. The computer may then control the pump to ensure that all parts of the lawn receive sufficient water or provide data as to the performance of individual trays or for any other purpose.

Because the amount of water discharged from the conduits is relatively small, there will not be a significant drop in the pressure of the water with distance from the pump. However, if watering a large area, it is possible to connect the pump to two or more trays lying on the perimeter of the lawn to maintain uniform water pressure over the entire irrigated area. -9 -

Claims

CLAIMS1. A modular subsurface irrigation system, comprising a plurality of inter-connectable trays each having a rigid peripheral open frame with upstanding sides, a capillary mat covering a lower end of the frame, at least one water conduit connected between opposite sides of the frame, connection ports in the conduit for enabling fluid communication to be established between conduits of adjacent trays, and perforations or a permeable member to allow water to leak from the conduit onto the capillary mat, wherein the conduit comprises two mating parts, a first part being formed integrally with the sides of the tray and being shaped as a channel open on its side facing the top or the bottom of the tray and a second part being a cover that serves to close the channel so as to complete the conduit, and wherein one of the parts is porous, perforated, or fitted with porous members to allow a slow controlled leakage of the water from the conduit onto the capillary mat.
2. An irrigation system as claimed in claim 1, wherein the trays are made of a plastics material that is not bio-degradable.
3. All irrigation system as claimed in claim 2, wherein the plastics material is high density polyethylene.
4. An irrigation system as claimed in claim 2 or 3, wherein the sides and the first part of the conduit are formed by injection moulding.
5. An irrigation system as claimed in any preceding claim, wherein the cover is formed of RITE.
-10 - 6. An irrigation system as claimed in any preceding claim, wherein the capillary mat is made of a non-woven synthetic fleece material.
7. An irrigation system as claimed in Claim 6, wherein the mat is 5 made of PET.
8. An irrigation system as claimed in any preceding claim, wherein the connection ports are upwardly facing female sockets for use with connectors in the form of short pipe with a U-bend, the end of each limb of the connector being configured for insertion into the female socket of a respective one of two contiguous trays.
9. An irrigation system as claimed in Claim 8, wherein a watertight seal is achieved by the use of 0-rings that are compressed between the 15 connectors and the sockets.
10. An irrigation system as claimed in any preceding claim, wherein notches are formed in the upper edges of the sides of the frame to receive connectors so as to avoid connectors protruding above the upper end of the 20 frame.
11. An irrigation system as claimed in any preceding claim, wherein each tray is formed with multiple conduits.
12. An irrigation system as claimed in Claim 11, wherein each tray is square and has two conduits extending parallel to one another between a first pair of opposite sides of the square and two further conduits extending parallel to one another between the other pair of sides at right angles to the first two conduits.
13. An irrigation system as claimed in Claim 12, wherein 5 intersecting conduits are in fluid communication with one another at their intersection.
14. An irrigation system as claimed in any preceding claim, wherein each tray further comprises a data bus for enabling a moisture sensor fitted to 10 the tray to communicate with a central computer.