Technical Field

The present invention relates to a surface water drain. In particular, the present invention relates to a surface water drain that prevents the build-up of small debris such as sand or dust inside the gully below the drain.

Background to the Invention and Prior Art

A surface water drain or storm water drain are drainage systems that are designed to drain rain water and ground water from impermeable surfaces that are unable to absorb large amounts of water. Examples of such surfaces include streets paved with stone or brick, or tarmac surfaces such as roads or car parks. As such, in countries where there are periods of heavy rainfall, it is important to have these drainage systems in place to prevent flooding. An example of a surface water drain 1 known in the art is shown in Figures 1 and 2.

In Figure 1, two gratings 10, 12 are embedded in an impermeable surface 14 such as a road or pavement. Rain water or other ground water falls through slots 16 between the gratings 10, 12. Directly below the gratings 10, 12 are two filter baskets 18, 20 with a number of small holes 22 provided in the sides of the baskets 18, 20. As water pours into the baskets 18, 20, the water drains into two large interconnected tanks or gullies 24, 26 located directly below the baskets 18, 20. When the water reaches a certain level, it overflows into a drainage pipe 28 which takes the water away from the drain, for example, to a sewer, water treatment facility or to a natural body of water (lake, river, canal, ocean, etc.).

The slots 16 in the gratings 10, 12 are typically large enough that some debris such as leaves or litter can also fall into the baskets 18, 20. However, the holes 22 in the baskets 18, 20 prevent this debris from going any further. The baskets 18, 20 can be emptied periodically to prevent a build of debris in the tank or gully 24, 26 below the drain 1 and thereby prevent the drain 1 from becoming blocked.

Smaller sediment such as dust or sand will be able to fall through the holes 22 of the filter baskets 18, 20 into the gullies 24, 26. Generally, small amounts of this sediment will get washed away down the drainage pipe 28 with frequent rainfall. However, this can be problematic in countries, for example, in the Middle East, where rainfall only occurs on a small number of days a year and/or have a very sandy or dusty terrain. In such cases, during the dry season, sand or dust gradually fills up the gullies 24, 26 and the filter baskets 18, 20, consequently blocking the drain 1. When rainfall does eventually occur, the water is unable to wash away this large amount of sediment, and therefore the water is unable to drain away. In extreme cases of very heavy rainfall, such blockages can cause the road surfaces to flood due to the lack of functional drainage points.

Summary of the Invention

Embodiments of the present invention address the above noted problems by providing a moveable insert that blocks the entrance of the drain to prevent any debris or sediment from entering the drain when there is no rainfall or surface water. Any sediment that does settle on top of the drain will be regularly swept up away, either naturally by the surrounding environment or intentionally, for example, by a road sweeper. As such, there will never be a build-up of sand or dust large enough to move the insert. When there is rainfall or surface water, the weight of any water sitting on top of the insert causes the insert to move to thereby create an opening through which the water can flow.

In a first aspect of the present invention, a surface water drain is provided, comprising an inlet through which water and sediment can pass, and a moveable part arranged to move between a first position and a second position, such that in the first position the moveable part seals the inlet to prevent sediment from entering the drain, and in the second position the moveable part unseals the inlet to thereby allow water and sediment to enter the drain.

Consequently, the drain can be sealed to prevent anything from entering it. This means that when there is no rain or surface water to be drained, the drain can be sealed to prevent sediment from building up in the gully or tank that may be located below the inlet.

In the presence of water at the inlet, the weight of said water may cause the moveable part to move from the first position to the second position. That is to say, when there is rain or surface water resting on top of the inlet, the weight of this water causes the drain to be opened so as to allow the water to enter.

Conversely, when there is no water resting on top of the inlet, the moveable part remains in the first position so as to keep the drain sealed. To facilitate this, the moveable part may be resiliency biased into the first position. In some arrangements, the moveable part may be resiliency biased into the first position by means of a spring loaded mechanism.

Therefore, in the presence of water, the weight of said water pressing on the moveable part acts against the force of the spring loaded mechanism so as to move the moveable part from the first position to the second position. Once the water has entered the drain and there is no more water pressing on the moveable part, the moveable part returns to the first position to seal the inlet once more.

In some arrangements, the inlet may be a grated inlet comprising a plurality of apertures, wherein the moveable part is configured to fill the plurality of apertures when the moveable part is in the first position so as to form a seal between the grated inlet and the moveable part.

In other arrangements, the inlet may be a side inlet for installation on a corner, the side inlet having at least one aperture, wherein the moveable part is configured to fill the at least one aperture when the moveable part is in the first position so as to form a seal between the side inlet and the moveable part. Additionally, the moveable part may be rotatable about a spring lever coupled to the side inlet.

The inlet may sit above a sub-surface drainage system. For example, a sub-surface drainage system comprising a water collection chamber and a drainage pipe.

The moveable part may be made of one of a foam material, a plastic material, a metallic material, a synthetic material, a metal and a fine mesh material. In a second aspect, a surface water drain is provided, the surface water drain comprising a grating through which water can enter, and a moveable grating filler element resiliency biased towards the grating such that the filler element interlocks with the grating to thereby close the drain, the filler element being further arranged to yield under the weight of water such that it disengages with the grating to thereby open the drain. In a third aspect, a surface water drainage system is provided, comprising a sub-surface chamber buried beneath an impermeable surface, a frame for installation within the surface to thereby provide an entrance to the sub- surface chamber from the surface, the frame having an inlet through which water can pass into the chamber, characterised in that the system further comprises a moveable insert arranged to move between a first and a second position so as to open and close the inlet.

Brief description of the Drawings

Further features and advantages of the present invention will become apparent from the following description of embodiments thereof, presented by way of example only, and by reference to the drawings, wherein:

Figure 1 illustrates a prior art surface water drain;

Figure 2 is a cross-sectional view of the prior art surface water drain of Figure 1;

Figures 3A-B illustrate a surface water drain according to a first embodiment of the present invention;

Figures 4A-B are a first cross-sectional view along the Y-axis of part of the surface water drain of Figures 3A-B;

Figures 5A-B are a second cross-sectional view along the X-axis of part of the surface water drain of Figures 3A-B; Figures 6A-B illustrate a surface water drain according to the first embodiment in use; Figure 7 illustrates a surface water drain according to a second embodiment; Figure 8 illustrates a surface water drain according to a third embodiment; Figures 9A-C illustrate a second prior art surface water drain;

Figures 10A-B are cross- sectional views of a surface water drain according to a fourth embodiment of the present invention;

Figure IOC is a front view of a surface water drain according to the fourth embodiment;

Figure 10D illustrates a surface water drain according to the fourth embodiment in use;

Figure 11 illustrates a surface water drain according to a fifth embodiment. Detailed Description of the Drawings

Figures 3A-B illustrate a first surface water drain 100 according to the present invention. The drain 100 comprises a metal frame 102 and an insert 104. The metal frame 102 may be made of any material suitable for installation along a road or the like, for example, a cast iron or ductile iron material. The insert 104 is made of a foam or plastic material, or alternatively, a meshed material, preferably one that is capable of only allowing a small amount of water through. The frame 102 is made up of a hollow box portion 110 consisting of four walls that extend down in to a lip portion 112 at the base of the frame 102. A metal grate 106 sits over the top of the box portion 110, which acts in the same way as the gratings of the prior art; that is, to form an inlet that only allows water and small debris through. The insert 104 sits within the box portion 110 underneath the metal grating 106. As illustrated by the cross-sectional views of figures 4A-B and 5A-B, the insert 104 comprises cut outs 114 that correspond to the shape of the metal grate 106. As such, when the insert 104 is fully inserted to the box portion 110, the metal grate 106 itself extends downwards into the insert 104 and the top surface of the insert 104 fills the gaps 107 between the metal grate 106.

The insert 104 is coupled to the frame 102, however, this coupling is such that the insert 104 is capable of moving relative to the frame 102. This coupling may be provided in any suitable way, for example, one or more pins or bolts 108 connected to the corners of the metal grate 106, the insert 104 being arranged to slide along the length of the pins 108, as will now be described.

Figures 6A-B illustrate a surface water drain 200 of the present invention in use. As before, the drain 200 comprises a metal frame 202 and an insert 204. The frame 202 comprises a hollow box portion 210 and a lip portion 212 for anchoring the frame 202 within an impermeable surface 224 such as a road or pavement. The frame 202 also comprises a metal grating 206 positioned over the top of the box portion 210. In its first position, as shown in Figure 6 A, the insert 204 sits within the box portion 210 such that the legs of the grating 206 extend down into cut outs 214 in the top of the insert 204, with the insert 204 filling the gaps 207 in the grating 206. In this first position, the insert 204 prevents any small or large debris from falling down through the grating 206 and into a gully or tank 226, or some other water collection chamber, buried in the ground below the drain 200. The insert 204 is coupled to the frame 202 via a plurality of pins, for example, four pins 208 (only two shown here) connected to the corners of the grating 206, and which extend down through a channel 205 in the insert and out through the bottom of the insert 204 into the tank 226. Each pin 208 is threaded through an upper washer 218, a spring 222, and a lower washer 220. The bottom of the pin 208 can be mounted to a fixed block 216 which sits on top of a raised platform 228 located at the bottom of the tank 226 to provide additional stability to the arrangement. The insert 204 is movable such that it is capable of sliding down along the pins 208, thereby compressing the spring 222 between the upper washer 218 and the lower washer 220. In this respect, the upper and lower washer 218, 220 act to distribute the load exerted on the insert 204 to ensure the spring 222 does not damage the base the of the insert 204, for example, by piercing the insert 204, or vice versa. Alternatively, the pin 208 may be simply attached to the lower washer 220 without the block 216 or raised platform 228 such that it hangs down freely below the insert 204, as shown by way of example in Figure 11.

When rainfall occurs, the weight of any significant amounts of water (insofar that drainage is required) resting on top of the drain 200 causes the insert 204 to be pushed downwards against the force of the springs 222, as shown in Figure 6B. In doing this, an opening 232 into the tank 226 is created through which water flowing through the grating 206 can enter. Some small sediment may also be able to get through this gap 232, however, it will be easily washed away with the draining water. Similarly, some small sediment may get into the cut outs 214, but will also be easily washed away with the draining water. Once the water in the tank reaches a certain level, it will start to drain away via a drainage pipe 230 provided so as to remove water from the tank 226, for example, to a sewer, water treatment facility, or a natural body of water. As the rain has stops and the surface water drains away, the insert 204 will gradually return to its original position, once again blocking the drain 200. As a result of this arrangement, when there is no rain or surface water to be drained, the drain 200 is effectively blocked by the insert 204 thereby preventing any debris of any size from building up inside the tank 226 and blocking the drain 200 altogether. As such, the present invention also removes the need to include a catch basin in the tank 226 that needs regular emptying to remove larger debris. Figures 7 and 8 show alternative arrangements to that of Figures 6A-B. Here, equivalent features are given equivalent numbering to the arrangement shown in Figures 6A-B, but with the first digit replaced with a 3 in Figure 7 and a 4 in Figure 8, rather than the 2 used for Figures 6A-B.

Figure 7 shows an alternative arrangement of a surface water drain 300 in which the insert 304 is coupled to the frame 302 by means of a hooked rod 308 that hooks over the edge of the hollow box portion 310 such that the hook portion 309 is anchored into the road surface 324. The end of the rod 308 extends down through a channel 305 in the insert 304 and out through the base of the insert 304. As with the arrangement shown in Figures 6A-B, the rod 328 is threaded through an upper washer 318, a spring 322 and a lower washer 320. The rod 308 can be mounted to a fixed block 316 on top of a support platform 328 at the bottom of the tank 326. As such, when water presses down on the insert 304, the insert 304 moves downwards such that the spring 322 is compressed between the fixed block 326 and the insert 304. As before, the upper and lower washer 318, 320 act to distribute the load exerted on the insert 304 by the spring 322 as the insert is pushed downwards into the tank 326, thereby preventing any damage to the insert 304 by the spring 322, or vice versa. Alternatively, the pin 308 may be simply attached to the lower washer 320 without the block 3216 or raised platform 328 such that it hangs down freely below the insert 304.

Similarly, in Figure 8, the insert 404 is coupled to the metal frame 402 by means of a hooked rod 408. However, in this arrangement, the hook portion 409 of the rod 428 is hooked around one of the metal gratings 406. The end of the rod 408 extends down through a channel 405 in the insert 404 and out through the base of the insert 404. As with the arrangement shown in Figures 6A-B, the rod 428 is threaded through an upper washer 418, a spring 422 and a lower washer 420. The rod 408 can be mounted to a fixed block 416 on top of a support platform 428 at the bottom of the tank 426. As such, when water presses down on the insert 404, the insert 404 moves downwards such that the spring 422 is compressed between the fixed block 426 and the insert 404. As before, the upper and lower washer 418, 420 act to distribute the load exerted on the insert 404 by the spring 422 as the insert 404 is pushed downwards into the tank 426, thereby preventing any damage to the insert 404 by the spring 422, or vice versa. Alternatively, the pin 408 may be simply attached to the lower washer 420 without the block 416 or raised platform 428 such that it hangs down freely below the insert 404. As with the pin 208 of Figures 6A-B, the hooked rods 308, 408 in both Figures 7 and 8 act to hold the insert 304, 404 in place, whilst also providing the insert 304, 404 with a guide along which it can travel as it is pushed downwards into the tank 326, 426 by the weight of any water resting on top.

It will be appreciated that Figures 6A-B, 7 and 8 all show one way of implementing the present invention, and that the moveable insert may be installed within a drain in any suitable way provided that it is moveable from a first position where it blocks the drain to a second position where water is allowed to enter the drain, the insert only moving to the second position when there is rain water or surface water to be drained.

Figures 9A-C show a further prior art surface water drain 500, suitable for installation on the curb 514 formed where two surfaces at different levels meet. The drain 500 comprises a metal frame 510 for mounting the drain 500 to the curb 514 at the side of a road 516. The frame 510 is made up of a hollow box portion 511 consisting of three walls that extend down into a lip portion 512 at the base, with the absence of a fourth wall providing the inlet 501 through which water can enter the drain 500, and a retaining bar 509 for securing the entrance 501 of the drain 500 to the lower road surface 516. This bar 509 also acts as a blocking mechanism to help prevent debris and sediment from entering the drain. The drain 500 also includes a moveable lid 502 comprising a top plate 504 that is rotatable about a pivot point 506. At the entrance 501 of the drain 500, the lid 502 extends down into a row of elongate members 508 provided so as to partially block the entrance 501 into the tank or gully 518 provided below the drain 500. These elongate members 508 are large enough so as to prevent large debris from entering the drain 500. Behind the elongate members 508, a plurality of fingers 505 extend down perpendicular to the top plate 504 to further aid the filtering provided by the elongate members 508. However, as before, smaller sediment and debris can easily pass through the entrance 501 and build up inside the tank 518.

Therefore, to address the problem of sediment build up in the case of curb side drains, the lid 602 of the drain 600 is provided with a spring loaded mechanism 622 located at the entrance 601, the spring loaded mechanism 622 comprising a gate 623 and a spring lever 624, as shown in Figures 10A-D.

The gate 623 is made of a material such as plastic, foam or a fine mesh, and is configured to fill the gaps between the elongate members 608 at the entrance 601 of the drain 600, as illustrated in Figure IOC. As such, the gate 623 effectively blocks the entrance 601 to the drain 600 to prevent debris or sediment from entering the drain 600. The rest of the drain 600 is the same as other curb side drains known in the art, comprising a metal frame 610 for mounting to the curb 614, a rotatable lid 602 and a bar 609 for partially blocking the entrance 601 of the drain 600, thereby acting as a secondary mechanism for stopping debris and sediment from entering the drain 600. Below the drain 600, a tank 620 is provided with a drainage pipe 618 for removing excess water. In this respect, equivalent features are given equivalent numbering to the prior art arrangement shown in Figures 9A-C, but with the first digit replaced with a 6, rather than the 5 used for Figures 9A-C.

In use, when rain or surface water exerts a weight on the gate 623, the weight of the water pushes against the force of the spring lever 624 and causes the gate 623 to rotate inwards in the direction of arrow A, as shown in Figure 10A. In doing this, an opening 626 into the drain 600 is created, as illustrated by Figure 10B, thereby allowing the water to enter the drain 600 and pour into the tank 620. When there is no rain or surface water present, the force of the spring lever 624 pushes the gate 623 back to its original position, thereby preventing any debris or sediment of any size from entering the drain 600 and building up inside the tank 620. As such, the gate 623 acts in the same way as the insert 104, 204, 304, 404 illustrated by the arrangements shown in Figures 2A to 8.

Again, it will be appreciated that Figures 10A-D shows one way of implementing the present invention in a curb side drain, and that the moveable gate 623 may be installed within the drain in any suitable way provided that it is moveable from a first position where it blocks the entrance to the drain to a second position where water is allowed to enter the drain, the gate 623 only moving to the second position when there is rain water or surface water to be drained.

Various modifications, whether by way of addition, deletion and/or substitution, may be made to all of the above described embodiments to provide further embodiments, any and/or all of which are intended to be encompassed by the appended claims.