GB2577639A

GB2577639A - Slot drain

Info

Publication number: GB2577639A
Application number: GB1915319.6A
Authority: GB
Inventors: Carter Justin; Aston Stott Paul
Original assignee: Ddj Ip Ltd
Current assignee: Ddj Ip Ltd
Priority date: 2017-09-18
Filing date: 2017-09-18
Publication date: 2020-04-01
Anticipated expiration: 2037-09-18
Also published as: GB2577639B; GB201915319D0

Abstract

A slot drain 100 comprises a throat section 10 having two opposing side walls reinforced by at least one bridging member 40, and a drainage conduit 20. The drainage conduit is in fluid communication with the throat section via one or more drainage inlets (30, Figure 3), and the throat section comprises a first material for example stainless or galvanized sheet steel. The side walls 11 of the throat section have attachments to connect to the drainage conduit 20. The drainage conduit comprises a second material different to the first material of the throat section, such as a polymer like high density polyethylene (HDPE). The drain may also comprise feet 60 which along with the bridging members are also made of sheet steel, and are riveted, bonded, glued, or welded to the drainage conduit. The slot drain may also comprise a cast drainage grate 70 with slots.

Description

SLOT DRAIN

Field of the invention

This invention relates to drainage and slot drainage. In particular, though not exclusively, the invention relates to a modular slot drain unit, as well as uses of the same.

Background of the invention

Slot drains allow surface liquids, usually large volumes of rain water, to be collected and removed quickly, where otherwise the liquid might become a nuisance or even dangerous.

Slot drains usually have a relatively narrow opening at ground level, typically a linear slot for collecting liquids. The opening directs the collected liquid down a throat portion and into an underground conduit, the conduit directing the water to another location. The conduit is sized to deal with the volumes of liquid expected. Slot drains tend to be placed in a trench and fixed in place by embedding in concrete, which supports and secures the slot drain. The concrete can be finished by covering over with a material like asphalt or blockwork, so long as the slot remains free to receive surface liquids. The open mouth of the slot drain is usually covered over with a protective metal grate.

The slot drain has a narrow opening so that traffic moving over and around the area of the slot drain is not inconvenienced.

High loads and slow turning movements passing over the slot drain can however cause damage to the slot drain. This is a particular problem during installation of the slot drain, where heavy equipment may travel over the slot drain. Drainage is often installed before the completion of other heavy work, and so heavy machinery may pass over the slot drain area multiple times. Slot drains are especially vulnerable to damage when they have not yet been fully embedded in protective concrete, the concrete is typically applied in stages. As a further complication, the sheer weight of the protective concrete can also cause damage to the slot drain.

GB2311549 discloses a metal slot drain. This slot drain is made from two pieces of sheet steel, which are bent and joined together. Metal is expensive and heavy, making the manufacture and transport of the slot drain expensive and difficult.

GB2390630 discloses a plastic slot drain. Plastic is cheap but not very strong (does not have inherent strength), and so is more likely to break or fail, especially during the period of installation. To address the lack of strength, the slot drain in GB2390630 is reinforced. The reinforcement is effectively achieved by allowing channels of concrete to extend through the throat walls. In this way a 'structural bridge' is formed that passes through the throat walls. The structural bridges help to support the weight of the heavy concrete slabs that overhang the slot drain.

To do this, the slot drain in GB'630 needs a very complicated shape, in particular a complicated throat shape that resembles a viaduct shape. That is, it has a throat section with a series of archways through it. However, unlike a viaduct, the structures between the archways are hollow and are used to transport liquid down to the drainage conduit.

To make a slot drain with this intricate shape requires a complex manufacturing process such as rotomoulding, and involves chemicals that allow the device to be released from the manufacturing equipment. Also, the series of trumpet-like tubes in GB'630 restrict the water flow, producing a throttling effect, which slows liquid transport. Plastic is also buoyant making fixing in concrete difficult.

There remains a need in the art for improved slot drains. Summary of the invention In a first aspect of the invention, there is provided a slot drain comprising, a throat section, comprising two opposing side walls reinforced by at least one bridging member, and a drainage conduit, wherein the drainage conduit is in fluid communication with the throat section via one or more drainage inlets, and wherein the throat section comprises a first material and the drainage conduit comprises a second material, and wherein the first material and second material are different.

The present invention provides a slot drain that can be tailored to user need. The structural requirements of the throat section and drainage conduit of a slot drain are not the same.

When embedded in concrete, the throat section of the slot drain is required to withstand the forces created by having concrete slabs on either side of the throat, these acting to prevent the crushing of the throat section. The throat section is also liable to receive the impact from loads traveling over the slot drain. This is especially the case during installation, when the throat section may be crushed by heavy machinery.

By contrast, the drainage conduit is largely shielded from these detrimental forces and so does not need to be as robust as the throat section.

By choosing suitable materials for the throat section and suitable materials for the drainage conduit, the following benefits can be realised by the invention (i) the cost of production and installation can be reduced; and/or (ii) the shape of the slot drain can be simplified, again saving on cost; and/or (iii) repairs can be made more easily; and/or (iv) better engagement with the fixing material (i.e. concrete) can be achieved; and/or (v) the buoyancy problems addressed. These benefits will be further explained with reference to the following embodiments of the invention.

In an embodiment the throat section comprises at least about 25%, 50%, 75%, 90%, 95% or 99% of the first material by mass, optionally, the throat section substantially consists of the first material. In an embodiment the drainage conduit comprises at least about 25%, 50%, 75%, 90%, 95% or 99% of the second material by mass, optionally, the drainage conduit substantially consists of the second material. In some situations, the benefit provided by the first material and/or second material can be achieved when the first material and/or second material are present at a level below 100%, and the lesser amount of the material may save on costs. Joining materials (and/or other materials), like bolts, rivets, welds or glue might also be present in the slot drain, and thereby accounting for a partial amount of the mass of the slot drain.

In an embodiment the first material comprises metal.

Metals tend to be strong and resistant to damage, and so is an advantageous material to make the throat section of the invention from. Even if damaged there is also the possibility of bending the metal section back into position, or the damaged section could be removed and replaced, or even cut out and patched over. By contrast, materials like plastic tend to be brittle and tend to break irreparably. Therefore, in the case of a material like plastic, when the throat section is damaged there may be little choice but to dig the slot drain out of the ground and replace the whole drain section, a costly and time consuming process.

In addition, because a metal throat section can be made more robust than a plastic throat section, complex throat shapes like those in GB'630 are not required. That is a structural bridge through the throat section is not required. Therefore, metal throat sections can have a simpler design than plastic throat sections, e.g. simple metal sheet walls. Simplifying manufacture and hence cost.

Metals, tend to have thermal expansion coefficients that are close to the thermal expansion coefficient of concrete, concrete being the primary fixing material used in slot drain fixing. The thermal expansion coefficients of plastic tend to be quite dissimilar to those of concrete. As concrete sets it generates heat. In the case of plastic, this means that quite a large gap can form between the plastic and the concrete slab. In the case of a metal (with a similar thermal expansion coefficient to concrete) the resultant gap can be quite small, or not present.

Having a gap between the throat wall and concrete slab creates an area of weakness, it potentially allows the throat wall to move with respect to the concrete slab and this, when under a load, could cause damage to the slot drain. Bigger gaps increase the chance of damage occurring.

As mentioned above, slot drains like those in GB'630 require a releasing agent (to free the unit from the mould during manufacture). The presence of the releasing agent will make it difficult for any material to stick to the slot drain. Therefore, a releasing agent makes the adhesion of concrete more difficult. A metal throat will not be coated in a releasing agent and so this problem is also avoided.

In addition, a plastic slot drain is quite buoyant. This can pose problems in fixing the slot drain in place. Having a heavy, e.g. metal throat section, can help weigh the slot drain down and so help with embedding the slot drain in concrete, in part addressing the buoyancy problem of plastic.

In an embodiment, the second material comprises a non-metal, optionally the non-metal is a polymer, further optionally the polymer is a plastic.

Polymeric materials such as plastic are cheap, flexible and can be made readily into various shapes, and so is a good material to make drainage conduits from. Drainage conduits do not need to be as strong as the throat section for the reasons explained above. While metals are robust, they are expensive, heavy, non-flexible and difficult to shape. Therefore, metals are needlessly strong, more expensive and do not have properties that are ideal for making drainage conduits. Also, the cost and difficulty of using metal in a drainage conduit increase quickly as the size of the conduit increases.

In an embodiment the first material comprises a metal and the second material comprises a non-metal. This embodiment allows the most functionally appropriate materials to be used in the most suitable location in the slot drain. Therefore, this embodiment provides the benefit of a robust throat section and a cheap and flexible, potentially massed produced plastic material, to make the drainage conduit from.

In an embodiment the first material comprises a non-metal and the second material comprises a non-metal, and wherein the non-metals are different, optionally the non-metal is a polymer, further optionally the polymer is a plastic. This embodiment allows for the use of a non-metal (e.g. a plastic) in the throat section which is different to the non-metal (e.g. a plastic) used in the drainage conduit.

For example, (i) the plastic in the throat section may be a different kind of plastic to the plastic in the conduit (e.g. using different monomer bases, or different levels of cross-linking, or contain different additives or different co-polymers etc.); or (ii) the plastics might be the same kind of plastic but the one in the throat section may be of a higher grade/specification; or (iii) the plastic in the throat section may have some advantageous chemical or physical property, like a thermal expansion coefficient that is close to the thermal coefficient of concrete; or (iv) the first material may be made by one process of manufacture, whereas the second material may be made by another, or simpler manufacturing process, these processes providing different internal structures to the plastic, so making them different. Plastic manufacturing processes include rotomolded, extruded, and injection/vacuum moulded In an embodiment the metal is selected from any one of steel, stainless steel and galvanized steel.

In an embodiment the first material is a polymer; and optionally the polymer is selected from polyethylene, high-density polyethylene (HDPE), and polypropylene.

In an embodiment the second material is a polymer; and optionally the polymer is selected from polyethylene, high-density polyethylene (HDPE), and polypropylene.

In an embodiment the drainage conduit is textured, ribbed or corrugated. A drainage conduit with a non-smooth surface allows fixing materials like concrete to key into the walls of the drainage conduit more firmly. In an embodiment the drainage conduit is a pipe, optionally the pipe may be ribbed or otherwise textured to allow the ingress of the fixing material In an embodiment the drainage conduit is ribbed, the ribs extending up to about 5%, 10%, 15%, 20%, 25%, 30%, 40%, 50%, 75%, 100%, 125%, 150%, 200%, 300%, 400%, or 500% beyond the walls of the drainage conduit.

In an embodiment the drainage conduit is a twin walled pipe, having an inner wall and an outer wall. Optionally, the outer wall is ribbed. In an embodiment the inner wall of the twin walled pipe is about 1mm to 10cm thick, optionally about 3mm to 3cm thick. In an embodiment the outer wall of the twin walled pipe is about 3mm to 20cm thick, optionally about 5mm to 10cm thick.

In an embodiment the drainage conduit has a cross-section which is substantially circular, oval, egg-shaped or polygonal. In an embodiment the drainage conduit has a cross-section which is substantially a triangle, square, kite, rectangle, pentagon, hexagon, heptagon or octagon. Optionally, when the drainage conduit has a polygonal cross-section, one angle of the polygon is located at the

S

lowest point of the conduit. The invention provides for drainage conduits with various shapes. A drainage conduit with a circular cross-section (i.e. the plane vertically-orthogonal to the longitudinally extending direction of the drainage conduit) is a convenient shape to manufacture. However, when the conduit has a relatively low volume of liquid to transport, it can be difficult to generate a sufficient hydraulic head to allow the liquid to drain away efficiently. Having a cross-sectional shape with a substantially angular bottom can improve the overall hydraulic head, leading to better drain away. For example, a conduit with an inverted egg-like cross-section means that low volumes of water gather in the narrowing side of the bottom of the egg to generate a good hydraulic head. As the volume of the liquid increases in the egg-like conduit, the effective cross-sectional size of the conduit widens, and so can easily cope with the increased volume. The smooth inside profile of the egg-like structure is also less likely to generate eddies or turbulences, and so prevent effective flow.

In an embodiment the drainage conduit has a widest internal cross-sectional dimension of 7cm to 105cm, optionally 10cm to 60cm.

In an embodiment the one or more drainage inlets are located substantially at or along the apex of the drainage conduit. The highest point on the conduit makes a convenient location to have the drainage inlets. In an embodiment the inlet is aligned vertically below the throat section. In an embodiment the throat section extends through the drainage inlet. In an embodiment, the inlets are substantially located at around the top surface of the drainage conduit. In an embodiment the drainage inlet is offset from the centre line of the drainage conduit.

In an embodiment the one or more drainage inlets are one or more openings along the length of the drainage conduit; optionally the openings are strips or slits along the length of the drainage conduit. In an embodiment the strips or slits are along at least a major part of the length of the drainage conduit; optionally, the strips or slits are along at least about 5%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 85%, 90%, 95% or 99% of the length of the drainage conduit. In an embodiment the strips or slits are along the full length of the drainage conduit. For efficient liquid drainage, it can be advantageous to have the area which communicates the water from the throat section to the drainage conduit to be as large as possible. Conveniently, a strip can be cut from (or a slit cut into) a circular pipe to form a large opening, to allow liquid to pass out of the throat section into the drainage conduit.

In an embodiment the side walls comprise attaching means to attach the throat section to the drainage conduit, wherein the attaching means engages within the drainage inlet. In an embodiment the walls of the slot drain are equipped with clasping feet which engage with the drainage conduit. In an embodiment, the clasping feet clasp/grip around a hole in the drainage conduit. In an embodiment the hole in the drainage conduit is a slit or slot that runs for the full length of the conduit and the clasping feet clasp along substantially the whole length of the slot. In an embodiment, the clasping feet are made of sheet steel have a substantially angular C-shaped cross-section. In an embodiment, the clasping feet are fixed to the lower portion of the side walls, for example by rivets, bolts, welds or are glued.

In an embodiment the side walls are sheets of material. The throat walls are conveniently made of sheet materials having sufficient properties to be self-supporting in an upright position, being sufficiently stiff and/or strong. Sheet materials are less bulky, use less material than a more substantial wall. In addition, this allows for a less bulky and hence compact design. This saves on the cost of the material and on transport costs. Unlike thick throat walls, material cannot effectively be scooped out of the sheet walls to make pockets in the walls, that can then be filled with concrete to make structural props. In an embodiment the walls are made of sheet steel and may be coated with a protective layer, for example the inside surface of the throat walls may be covered with a protective polymer layer, or the walls may be galvanized. In an embodiment the distance separating the side walls is greater than the thickness of the side walls. This can provide an efficient use of the available space. In an embodiment the length separating the side walls is at least ten times larger than the thickness of the side walls. In an embodiment the external surface of the side walls is roughened, e.g. scratched or textured. Roughening of the external surface of the side walls allows the fixing material (like concrete) to key onto the wall surface and to form a tighter bond. Such surface roughening is not sufficient to form a structural prop, as the scratches and the like are not deep. Metal as well as plastic side walls could benefit from such a keyed surface. In an embodiment the side walls are not pocketed. To allow for pocketing the side walls would need to be quite thick and so add to the bulk of the invention. In an embodiment the side walls are substantially smooth. Smooth side walls are conveniently made. In an embodiment the side walls are arranged symmetrically astride the longitudinal axis of the drainage conduit. A slot drain with symmetrically arranged side walls is conveniently made. However, it is also possible to have the slot arrange so that it is substantially off to one side of the drainage conduit. For example, this could be useful in circumstances where it is desirable to have the slot abutting a surface like a wall, but where the drainage conduit cannot (or it is not desirable for the drainage conduit to) be located under the wall.

In an embodiment the bridging member reinforces, i.e. supports the side walls by abutment. The side walls can be held apart and so supported by a member that extends between them, in effect buttressing the walls apart. The bridging member can be arranged such that it takes no load from above, but instead acts against any compressive forces acting in a direction horizontally-orthogonal to the longitudinally extending direction of the drainage conduit (i.e. resolved forces acting against the plane of the side walls). In an embodiment the bridging member comprises the first material. In an embodiment the bridging member comprises the first material and the side walls comprise the first material. In an embodiment the bridging member comprises the first material and the side walls comprise another material. In an embodiment the another material may be the second material or a third material. In an embodiment the bridging material may comprise less than about 1%, 2%, 5%, 7%, 10%, 15%, 20% or 25% of the mass of the slot drain. In an embodiment the bridging member comprises steel, stainless steel or galvanized steel, or could comprise plastics like polyethylene, high-density polyethylene (HDPE) and polypropylene.

In an embodiment the bridging member comprises at least one attaching plate, which attaches the bridging member to an internal surface of at least one side wall. The attaching plate allows for convenient attachment of the bridging member to the side walls, and can help to spread out the force being exerted. In an embodiment the bridging member is resilient. A resilient bridging member could be held securely between the throat walls by being held in a compressed state between the side walls. In an embodiment, the bridging member together with the attaching plates have a substantially angular n-shaped cross-section; or straightened Z-shaped cross-section or an H-shaped cross-section (e.g. see Figure 8). In an embodiment the bridging member is non-reversibly fixed to the internal surface of the side walls. That is, the bridging member is not intended to be removable from the slot drain under normal conditions, and to do so might entail a destructive force. The bridging member may be bolted, welded, riveted or glued between the internal (i.e. inside) surfaces of the side walls.

In an embodiment, no part of the bridging member passes through the side walls. Any portion of the bridging member that passes through the side walls could lead to areas of weakness, perforation of the side walls leads to less strong side walls. Holes in the side walls could also allow for the potential ingress of the fixing material into the interior of the slot drain during construction, and potentially liquid escaping from the slot drain in use after construction. Leaks could lead to potential detrimental long term erosion of the fixing material. In an embodiment, the bridging member sits wholly within the slot drain. In an embodiment, the bridging member sits wholly within the throat section between the side walls.

In an embodiment, the bridging member is attached to the side walls along at least about 95%, 90%, 75%, 50%, 40% or 25% of the height of the side walls. In an embodiment, the bridging member is attached to the side walls along at least the major part of the height of the side walls. The bridging member provides the most support to the side walls when it substantially extends the full height of the throat section. For ease of manufacture and assembly, in an embodiment, the bridging member may be less tall than the full height of the side walls. In addition, it can also be advantageous to have the bridging member fall short of touching the drainage conduit and/or the drainage grate. If the bridging member is in direct contact (i.e. touching) with the drainage grate this could result in top loads acting on the bridging member which could damage or dislodge the bridging member. If the bridging member is in direct contact with the drainage conduit, any top load acting on the bridging member could result in the downward force being transferred to the drainage conduit, which may in turn damage the conduit.

In an embodiment, the drainage conduit comprises one or more feet. The feet allow the belly of the drainage conduit to be raised off the surface it is placed on. Feet help with stability when the slot drain is placed in a channel prior to filling of the channel with a fixing material like concrete. Also, the feet allow concrete to flow under the drainage conduit giving the installed slot drain extra stability and protection, as this results in the slot drain being encased in a concrete slab.

In an embodiment, the feet have a base portion for sitting on the ground, a top portion for fixing to the drainage conduit, and a linker portion linking the base and top portions together. In an embodiment, the top portion has a conduit-attaching plate. The conduit-attaching plate allows for more convenient attachment of a foot to the drainage conduit, and allows pressure to be spread out. In an embodiment, the feet have a substantially angular pinched C-shaped cross-section. An embodiment of the feet is shown in Figure 11.

In an embodiment, the slot drain further comprises a mouth section in fluid communication with the throat section. In an embodiment, the throat section comprises the mouth section. Typically the top portion of the throat section can act as the mouth section of the slot drain, that is, the portion of the throat arranged to first receive the surface liquid. In some circumstances it can be desirable to adapt the mouth of the slot drain to better receive the surface liquid (e.g. to be flared), or it could be adapted to better cooperate with the drainage grate (e.g. having pins or ledges for the drainage grate to rest on), or the mouth could be adapted to prevent the slot from being fouled by debris.

In an embodiment, the slot drain further comprises a drainage grate in fluid communication with the mouth section, wherein the drainage grate comprises one or more grate openings. In an embodiment, the drainage grate straddles the mouth section and/or the sits within the mouth section. A drainage grate can help to protect the slot drain from damage, as vehicles and the like impact the grate and not the mouth/throat parts of the invention. In an embodiment, the drainage grate is non-reversibly fixed to the throat section; optionally the drainage grate is riveted or welded to the side walls. It can be convenient and/or beneficial to ensure that the drainage grate cannot move under normal operational conditions. If the drainage grate is dislodged, it could for example damage vehicles travelling over it, and/or cause travel disruption as well as a trip hazard.

In an embodiment, the drainage grate openings are slots, optionally the slots are arranged in parallel columns; further optionally the slots in adjacent columns are staggered. This embodiment can be seen in for example Figure 10. In a slot drain, liquids normally approach the slot in a direction horizontally-orthogonal to the longitudinal direction of the drainage conduit. This is because the slot is normally arranged to lie along the bottom edge of an inclined surface. Where the slots are staggered, this ensures that liquid does not simply bridge across the grate holes, thereby impeding efficient liquid collection. In an embodiment, the drainage grate comprises steel, stainless steel, galvanized steel or cast iron.. Cast iron (also known as ductile iron) is strong and durable and can withstand multiple impacts from loads without failing. It is also relatively inexpensive. Other suitable durable materials are also contemplated.

In an embodiment, the throat section comprises one or more slab conduits which pass into, and optionally through, the throat section, and wherein the slab conduits are not in fluid communication with the throat section, and which are adapted to receive a fixing material. As explained above, it can be useful in certain circumstances to reinforce the throat conduit by forming structural bridges through the throat section. Such structural bridges help to support the concrete slab on either side of the slot drain. In addition, reinforcing materials like rebar can be inserted through the slab conduits to provide additional support.

In an embodiment, the slab conduits are interrupted by a wall that partitions the bridge-forming slab conduits. In an embodiment, the slab conduits pass through a major part of the height of the walls of the throat section. In an embodiment, the bridge-forming conduits divide the throat portion into two or more independent throat portions.

In a second aspect of the invention, there is provided a slot drain of the first embodiment of the invention, wherein the slot drain is a modular unit arranged to couple with one or more modular units of the first and/or second aspect of the invention. The slot drain of the first aspect of the invention can be made as a modular unit, allowing a slot drain to be assembled by simply coupling the modules together. This can save on time and hence cost during an installation process. In particular, this can be useful where a large slot drain is needed and whereby assembling the slot drain as one piece would be impractical and time consuming. The modular units may be any length, optionally the unit is about 10cm, 20cm, 50cm, 100cm, 150cm, 200cm, 250cm, 300cm, 350cm, 400cm, 450cm, 500cm, 550cm or 600cm long. The throat assembly of the modular unit may be any height, optionally 5cm, 10cm, 15cm, 20cm, 25cm, 30cm, 35cm, 40cm, 45cm or 50cm tall. The drainage conduit of the modular units may have any internal cross-sectional dimension, optionally the widest internal cross-sectional dimension of the drainage conduit is about 5cm, 10cm, 15cm, 20cm, 22.5cm, 25cm, 30cm, 35cm, 37.5cm, 40cm, 45cm, 50cm, 55cm, 60cm, 65cm, 70cm, 75cm, 80cm, 8Scm, 90cm, 9Scm, 100cm, 110cm, 12Scm, 1S0cm, 17Scm or 200cm.

In an embodiment of the first and second aspect of the invention the slot drain is a unit, wherein the constituent parts of the unit are held in a fixed relationship. No moving (or removable) parts provide a robust unit, this simplifies slot drain assembly on site, whereby the parts cannot become lost and/or damaged. Time saved by the simple assembly of the modular units together on site ensures that the structure spends the minimum time in an exposed state (e.g. before it is full embedded in a fixing material like concrete). Slot drains are particularly prone to damage on busy construction sites when they are in an exposed state or partially exposed state.

In a third aspect of the invention, there is provided a slot drainage system comprising one or more slot drains according to the first or second aspect of the invention.

In an embodiment of the first, second or third aspect of the invention, there is provided a slot drain or slot drainage system which in use complies with one of the industry standards selected from A15; B125, C250, D400, E600 and F900, these standards being those defined as of 1 January 2017.

In an embodiment of the first, second or third aspect of the invention, there is provided a slot drain or slot drainage system which in use can withstand a force of 1.5kn, 12.Skn, 25kn, 40kn, 60kn or 90kn In an embodiment of the first, second or third aspect of the invention, there is provided a slot drain or slot drainage system, wherein the slot drain or slot drainage system is embedded in a fixing material, wherein the throat section is at or below a surface, wherein in use liquid at the surface is permitted to flow into the drainage conduit via the throat section, the throat section being open to the surface to receive liquids.

In a fourth aspect of the invention, there is provided a slot drain or slot drainage system according to any one of the first, second or third aspects of the invention, for use in any areas that require surface liquid drainage. In an embodiment, there is provided a slot drain or slot drainage system according to any one of the first, second or third aspects of the invention, for use in car parks, car washes, roads, motorways, bridges, ports, airport taxiways, factories, sports grounds or playing fields.

In a fifth aspect of the invention, there is provided the use of a slot drain or slot drainage system of any one of the first, second, third or fourth aspects of the invention.

In a sixth aspect of the invention, there is provided a slot drain, or slot drainage system substantially as herein described with reference to or as illustrated in the accompanying drawings.

The present invention will now be further described with reference to the following non-limiting examples and the accompanying illustrative drawings, of which:

Brief description of the drawings

Figure 1 is a perspective view of an embodiment of the invention.

Figure 2 is a partial exploded perspective view of an embodiment of the invention.

Figure 3 is a cross-section view of an embodiment of the invention.

Figure 4 is an exploded cross-section view of an embodiment of the invention.

Figure 5 is a perspective view of the throat assembly of an embodiment of the invention.

Figure 6 is a perspective view of the side walls part of an embodiment of the invention.

Figure 7 is a perspective view of the clasping feet part of an embodiment of the invention.

Figure 8 is a perspective view of the bridging member part of an embodiment of the invention.

Figure 9 is a perspective view of the drainage grate part of an embodiment of the invention.

Figure 10 is a top view of the drainage grate part of an embodiment of the invention.

Figure 11 is a perspective view of a foot part of an embodiment of the invention.

Like features have been given like reference numerals.

Detailed description of the invention

Figure 1 shows an embodiment (100) of the slot drain of the invention. The slot drain has a throat portion (10) connected to a drainage conduit (20) via drainage inlet (30), the drainage conduit is supported on three pairs of C-shaped legs (60), the top of the throat section is covered over by a n-shaped drainage grate (70), which straddles the mouth opening of the throat section (10).

The throat section (10) is made up of two opposed side walls (11) made of sheet steel, having an internal surface (11a) and an external surface (11b); between the opposed walls is a throat space (14) that is partially occupied by 7 bridging members (40), which are evenly distributed within the throat space, with one bridging member at each end. The bridging members (40) are riveted to the side walls (11).

The drainage conduit (20) is a ribbed pipe made of HDPE, having an external surface (21) and a ribbed internal surface (22). The pipe has a slot (30) cut along the apex line of the pipe. The pipe is 2 meters long.

C-shaped clasps (50) grasps around the cut edges of the pipe along the length of the pipe. A top portion (51) lies on the external surface (21) of the pipe, a midsection (52) lies over the cut edge of the pipe within the drainage hole (30) and a bottom portion of clasp (53) lies over the internal surface (22) of the pipe.

Side walls (11) have a L-shaped base (12) that lies over the top portion of the C-shaped clasp (51), these together (12, 51) are riveted to the drainage pipe.

The bridging members (40) is made of bent sheet steel and extend from one side wall (11) to the other via a bridge portion (42), and contacts the internal surface (11a) of the side walls (11), and thereby support them by buttressing. The bridging members (40) have attaching plates (41) that extend over the internal surface (11a) of the side walls (11), such that the bridging member has a substantially angular n-cross-section. The bridging members are riveted to the side walls. The bridging members has 4 lugs (41a, 41b, 41c, 41d) that extend from the attaching plates (41) to assist with coupling to another unit of the slot drain unit (100). These lugs ensure good coupling of one throat section to the throat section of another unit.

The feet (60) are made of sheet steel and have a bottom portion (61) that rests on the ground, a mid-portion (62) that links to the top portion (63), a fixing and locating plate (64) attaches to the top portion (63), with the fixing and locating plate (64) being riveted to the pipe. The feet are located at the end of the pipe and extend to allow for location and support of an adjacent pipe.

Drainage grate (70) is n-shaped (71) and made of cast iron and sits over the top of the throat section (40). The drainage grate has slots (72) in the metal body (73). The drainage grate (70) has raised markings (74) at each end.

The slots (72) are arranged in two columns with the slots being staggered in each column. The Drainage grate (70) is riveted to the side walls (11). Bridge-paths (75) between the slots in each column do not line up.

In use, surface liquids like rain water, traveling under gravity, meet the drainage grate (70) and pass through the grate holes (72) entering the throat mouth (80), the liquid then passes down through the throat cavity (14) between the side walls (11), and enters the drainage conduit (20) via the drainage inlet (30), the liquid is then directed by the drainage conduit (20) to another location where it is disposed of.

Figure 2 to Figure 11 show the same embodiment (100), or parts of the same embodiment, as shown in Figure 1. Like parts are given like numerals.

Figure 2 is an exploded perspective view of an embodiment (100) of the invention; Figure 3 is a cross-section view of an embodiment (100) of the invention; Figure 4 is an exploded cross-section view of an embodiment (100) of the invention; Figure 5 is a perspective view of the throat assembly of an embodiment of the invention; Figure 6 is a perspective view of the side walls (11) part of an embodiment of the invention; Figure 7 is a perspective view of the clasping feet (50) part of an embodiment of the invention; Figure 8 is a perspective view of the bridging member (40) part of an embodiment of the invention, and also shows different options for the bridging members (40-Z, 40-H); Figure 9 is a perspective view of the drainage grate (70) part of an embodiment of the invention; Figure 10 is a top view of the drainage grate (70) part of an embodiment of the invention and Figure 11 is a perspective view of a foot (60) part of an embodiment of the invention.

Claims

Claims 1. A slot drain comprising, a throat section, comprising two opposing side walls reinforced by at least one bridging member, and a drainage conduit, wherein the drainage conduit is in fluid communication with the throat section via one or more drainage inlets, and wherein the throat section comprises a first material and the drainage conduit comprises a second material, and wherein the first material and second material are different.
2. A slot drain of claim 1, wherein the throat section comprises at least about 25%, 50%, 75%, 90%, 95% or 99% of the first material by mass.
3. A slot drain of claim 1 or 2, wherein the drainage conduit comprises at least about 25%, 50%, 75%, 90%, 95% or 99% of the second material by mass.
4. A slot drain of any one of claims 1 to 3, wherein the first material comprises a metal and the second material comprises a non-metal.
5. A slot drain of any one of claims 1 to 3, wherein the first material comprises a non-metal and the second material comprises a non-metal, and wherein the non-metals are different.
6. A slot drain of any one of claims 1 to 4, wherein the metal is selected from any one of steel, stainless steel or galvanized steel.
7. A slot drain of claim 5, wherein the first material is a polymer; and optionally the polymer is selected from any one of polyethylene, high-density polyethylene (HDPE), and polypropylene.
8. A slot drain of any one of the preceding claims, wherein when the second material is a polymer; and optionally the polymer is selected from any one of polyethylene, high-density polyethylene (HDPE), and polypropylene.
9. A slot drain of any one of the preceding claims, wherein the drainage conduit is a pipe.
10. A slot drain of any one of the preceding claims, wherein the drainage conduit has a cross-section which is substantially circular, oval, egg-shaped or polygonal.
11. A slot drain of any one of the preceding claims, wherein the one or more drainage inlets are located substantially at or along the apex of the drainage conduit.
12. A slot drain of any one of the preceding claims, wherein the one or more drainage inlets are one or more openings along the length of the drainage conduit; optionally the openings are strips or slits along the length of the drainage conduit.
13. A slot drain of any one of the preceding claims, wherein the side walls comprise attaching means to attach the throat section to the drainage conduit, wherein the attaching means engages within the drainage inlet.
14. A slot drain of any one of the preceding claims, wherein the side walls are sheets of material.
15. A slot drain of any one of the preceding claims, wherein the bridging member comprises at least one attaching plate, which attaches the bridging member to an internal surface of at least one side wall.
16. A slot drain of any one of the preceding claims, wherein the bridging member is non-reversibly fixed to the internal surface of the side walls.
17. A slot drain of any one of the preceding claims, wherein the bridging member is attached to the side walls along at least about 95%, 90%, 75%, 50%, 40% or 25% of the height of the side walls.
18. A slot drain of any one of the preceding claims, wherein the drainage conduit comprises one or more feet.
19. A slot drain of any one of the preceding claims, further comprising a mouth section in fluid communication with the throat section.
20. A slot drain of any one of the preceding claims, further comprising a drainage grate in fluid communication with the throat section, wherein the drainage grate comprises one or more grate openings.
21. A slot drain of claim 20, wherein the drainage grate straddles the mouth section and/or the sits within the mouth section.
22. A slot drain of claim 20 or 21, wherein the drainage grate openings are slots, optionally the slots are arranged in parallel columns; further optionally the slots in adjacent columns are staggered.
23. A slot drain of any one of claims 20 to 22, wherein the drainage grate comprises cast iron.
24. A slot drain of any one of the preceding claims, wherein the throat section comprises one or more slab conduits which pass into, and optionally through, the throat section, and wherein the slab conduits are not in fluid communication with the throat section, and which are adapted to receive a fixing material.
25. A slot drain of any one of the preceding claims, wherein the slot drain is a modular unit arranged to couple with one or more modular units of any one of the preceding claims.
26. A slot drain of any one of the preceding claims, wherein the slot drain is a unit, wherein the constituent parts of the unit are held in a fixed relationship.
27. A slot drainage system comprising one or more slot drains according to any one of the preceding claims.
28. A slot drain or slot drainage system of any one of the preceding claims, which in use complies with any one of the industry standards selected from A15; B125, C250, D400, E600 and F900.
29. A slot drain or slot drainage system of any one of the preceding claims, wherein the slot drain or slot drainage system is embedded in a fixing material, wherein the throat section is at or below a surface, and wherein in use surface liquid is permitted to flow into the drainage unit via the throat section, the throat section being open to the surface to receive liquids.
30. A slot drain or slot drainage system of any one of the preceding claims, for use in any areas that require surface liquid drainage.
31. Use of a slot drain or slot drainage system of any preceding claim, to control surface liquids.
32. A slot drain or slot drainage system substantially as herein described with reference to or as illustrated in the accompanying drawings.