GB2333549A - Coupling assembly for drainage channel sections - Google Patents

Abstract

An assembly for coupling the open ends of two elongate channel sections (40) in a butted end-to-end manner, each channel section having a profile extending its entire length comprising a base (42) with inclined side walls (44) adjoining the base and sloping outwardly and upwardly away from the base to an open mouth. The assembly comprises a connecting block (2) having an upper supporting surface (6) shaped to receive an outer surface of the two butted ends of the channel sections, and clip means(24) are provided at each end of the block to engage outer flanges (50) of the channel sections to hold them against the block. A sealing mat (60) is laid over said supporting surface, which is compressed between the supporting surface of the block and the outer surface of the two butted ends, causing fins (68, fig. 3) on the mat to be bent, forming a labyrinth seal and preventing leakage from the connected channel sections. The assembly can be used for coupling plastic or metal drainage channel sections in the construction of drainage systems for internal use such as in hospitals, laundries ad changing rooms, requiring relatively few parts, and can be assembled on site with no specialist tools.

Description

DRAINAGE SYSTEMS The present invention relates to a method of connecting drainage channel sections together and an assembly for use in such a method.

In drainage systems for internal use such as in hospitals, laundries and changing rooms, the practice is to let shallow drainage channels into the floor and cover the open mouth with a slotted grill which allows easy entry of water or other fluids to be drained. The channels are, for ease of construction, generally made of separate sections which must be connected together. The conventional drainage channel section profile for such applications is a stainless steel rectangular section with vertical sides. In order to connect such channel sections together it is generally necessary to provide some end formations which allow the sections to be coupled. This requires welding and finishing processes which increase the overall expense of the channel section.

In the filed of connecting guttering section, there have been various proposals made for providing such a joint.

The technical problems posed by such guttering sections differ from the technical problems present when the drainage channel is let into a surface. An example of connecting blocks used for joining guttering sections can be found in GB-A-2 282 160. These guttering sections have a shaped end profile designed to co-operate with the block. Clips on the block also engage directly with the channel edge and protrude into the space within the gutter. This is not a problem with guttering as the gutter channel is primarily intended to conduct water and to also receive it from an adjacent roof surface. It is also impractical in the case of a drainage system let into a surface for any part of the connecting block to project above the channel surface as this would represent a trip hazard. Another technical problem associated with drainage systems let into a surface is the need for a secure seal. Seepage of liquid from the channel into the floor will cause substantial damage. Leakage from a joint in a gutter will cause only minimal inconvenience.

Gutters are also more accessible for maintenance purposes than permanently installed drainage channels iet into a surface.

The present invention is directed at providing an assembly which allows for easy coupling of channel sections on site and which is suitable for use with metal channel sections which can be formed by simple operations of cutting and folding only and require little or no specialist finishing since no end formations are required or channel sections formed by plastic extrusion.

In accordance with the present invention there is provided an assembly for connecting open ends of two elongate drainage channel sections adapted to be let into a surface; said drainage channel sections each having a profile extending along the entire length of the channel comprising a base with inclined side walls adjoining the base and sloping outwardly and upwardly away from the base to an open mouth; the assembly comprising a connecting block having an upper supporting surface shaped to receive an outer surface of two butted ends of the channel sections; clip means for holding the ends of the channel sections to the block; the clip means comprising a plurality of upstanding clips at each end of the block, each clip having an inwardly projecting nib adapted to engage with an outer flange at a respective side of the drainage channel section; and a sealing mat having a multiplicity of upstanding fins, which mat is laid over said supporting surface and is compressed between the supporting surface and the outer surface of the two butted ends in order to prevent leakage from the connected channel sections.

The present assembly has the advantage that it requires relatively few parts and can easily be assembled on site with no specialist tools. The connecting block is preferably a moulded plastics component that can be produced relatively cheaply. Other features of the present invention are defined in the appended claims.

In order that the invention may be well understood an embodiment thereof will now be described, by way of example only, with reference to the accompanying diagrammatic drawings, in which: Figure 1 shows a perspective view of a connecting block for use in the assembly of the present invention; Figure 2 shows a longitudinal section through the assembly of the present invention; Figure 3 shows a section along the line X-X in Figure 1; Figure 4 shows a section through a sealing mat in its free state; Figure 5 shows a detail of an alternative design of an end of the connecting block; and Figure 6 shows a section along the line Y-Y in Figure 5.

The drainage channel to be described is intended to be let into a floor surface which will be flush with an upper edge of the drainage channel.

A connecting block 2 has a rectangular base 4 and an upper channel supporting surface 6. The width of the base 4 is such that it is wider than a drainage channel section which is supported on its upper supporting surface 6. The block 2 is symmetrical and has two ends 8 which provide clip means shaped to interlock with outer edges of supported channel sections. The supporting surface 6 has a bottom portion 12 and outwardly inclined side surfaces 14 which follow the same shape as a profile of the channel section it is to support. Each side surface adjoins a land 16 parallel to the base 4 which merges with an upstanding flange 10 at a respective end 8.

At the other side of the flange 10 a groove 18 is formed and at each side of the block clips 20, 22 are formed with inwardly projecting nibs 24, 26 which project over the groove 18. The material between the two upstanding clips 20, 22 at each end 8 is cut away. In order to minimise the weight of the block bores 28 are formed in the solid material at each end beneath the side surfaces 14 and lands 16. These bores 28 traverse the block 2.

In addition slots 30 are moulded into the base and sides of the ends. A pair of slots 30 is shown at each end 8 but it will be appreciated that other methods of reducing the overall weight of material in the connecting block 2 can be employed.

An alternative design of the ends 8 that provides a levelling means is shown in Figures 5 and 6. In this embodiment there is a transverse bore 52 extending across the end below the supporting surface 6. The bore 52 is sized to receive a captive nut 54. The bore 52 intersects with a blind bore 56 which extends from the base 4 of the end towards the land 16. A levelling screw 58 having a foot 59 is received in the bore 56 and engages with the nut 54. Screwing the screw 58 relative to the nut adjusts the amount by which the foot 59 projects beyond the base of the block. The provision of levelling means as described at each end of the block allows the level of the block to be adjusted during the installation process.

The width of the bore 56 is slightly more than the across flat dimension of a full nut but prevents the nut 54 rotating with the screw.

The block 2 is designed to be used with stainless steel channel sections 40. A cross-section through a channel section 40 is shown in Figure 2. The profile of the channel section matches the profile of the supporting surface 6. Each channel section has a base bottom portion 42 and two outwardly sloping inclined side surfaces 44 which terminate in lands 46 parallel to the bottom portion 42. Beyond the lands at each end of the channel section the material of the channel section is folded to form a downwardly facing channel 48 which terminates in an outwardly projecting flange 50.

The channel sections may be cut or formed of any convenient length and have the same profile throughout their length.

The channel section is designed to fit loosely on the connecting block 2 so that the flanges 50 can engage with the clip means at either end 8 of the block 2.

A sealing mat 60 is also needed to complete the connection assembly. The sealing mat 60 comprises a flexible piece of plastics material shaped to follow the same general profile as that of the supporting surface 6 of the connecting block 2 and the channel profile. The mat 60 has a bottom portion and two side portions each adjoining a horizontal land and an L shaped end 66. On one face of the mat 60 a series of parallel resilient fins 68 are formed which extend along the whole length of the mat from one L shaped end 66 to the other. These fins 68 are illustrated in Figure 4 which shows a transverse section through the mat 60.

In order to connect open end faces of two identical channel sections 40 together end to end a connecting block 2 and a sealing mat are required. In the finished assembly the butt-joint between the two joined channel sections will lie substantially centrally in the connecting block. The first step is to place the sealing mat 60 on top of the supporting surface 6 of the block with its L shaped ends 66 supported on top of the flanges 10 at each end. The two channel sections are then placed on top of the mat 60 on the supporting surface 6. The channel sections are pressed vertically down onto the connecting block over the sealing mat so that the clips 20, 22 are pushed out sideways to allow passage of the flanges 50. The clips 20, 22 then resiliently snap back so that the nibs 24 retain the flange 50 in position. In order to facilitate the pushing of the clips 20, 22 laterally outwards an inner face 80 of each nib 24, 26 is given a sloping profile so that the clip will be moved gradually as its nibs engage with the edge of the flange 50. Alternatively the channel sections may be slid in so that for the first channel section the projecting flanges 50 on each side of the channel section engage under the nibs 24 of the clips 22 on each side of the supporting block. Similarly, the second channel section is brought in from the other side and its flanges 50 on each side engaged under the nibs 26 of the clips 20 on the other side face of the connecting block. However snap fitting is preferred.

When assembled the sealing mat is compressed between the supporting surface 6 of the connecting block 2 and the outer surface of each of the connected channel sections 40. The fins 68 of the mat 60 are resiliently bent so that a labyrinth seal is formed between the connecting block and the channel section which prevents leakage of water or other fluids within the drainage channel.

In order for the sealing to be effective it is necessary that the side walls of the channel are not vertical but incline away from the vertical preferably at an angle of at least 15 though an angle of 45" as shown is preferred.

This slope is necessary to reduce the shear effects on the sealing mat 60.

The presence of the upstanding flanges 10 keeps the clip means or strip hinge/nib arrangement which holds the assembly together away from the drainage channel.

In use the connecting block will be supported and held permanently in position by a concrete haunch into which the channel is inserted. Where levelling means are provided the levelling screws at each side of each block may be adjusted to level the channel before the concrete is poured.

The connecting blocks can be formed by injection moulding of a suitable plastics material such as glass-filled nylon, polyacetal or PVC.

The sealing mat 60 can be formed from a plastics material such as silicone rubber or EPDM by moulding as a discrete elongate strip of the required profile. A moulded seal ensures that the fins 68 do not collapse as happens when a normally straight section is bent through 900. The material of the sealing mat may need to be selected for corrosion resistance properties for use in certain environments. The drainage channel sections 40 may be formed from stainless steel and may readily be fabricated by conventional folding and pressing steps or be moulded plastics sections. The sections may be formed of any appropriate length for ease of handling and sections of different lengths can also be provided.

It will be appreciated that the prescribed connection assembly is simple to create requiring a supply of connecting blocks and sealing mats in addition to the channel sections.

Claims (5)

1. CLAIMS 1. An assembly for connecting open ends of two elongate drainage channel sections adapted to be let into a surface; said drainage channel sections each having a profile extending along the entire length of the channel comprising a base with inclined side walls adjoining the base and sloping outwardly and upwardly away from the base to an open mouth; the assembly comprising a connecting block (2) having an upper supporting surface shaped to receive an outer surface of two butted ends of the channel sections; clip means for holding the ends of the channel sections to the block; the clip means comprising a plurality of upstanding clips (22) at each end of the block, each clip having an inwardly projecting nib (24, 26) adapted to engage with an outer flange at a respective side of the drainage channel section; and a sealing mat (60) having a multiplicity of upstanding fins (68) which mat (60) is laid over said supporting surface and is compressed between the supporting surface and the outer surface of the two butted ends in order to prevent leakage from the connected channel sections.
2. 2. An assembly as claimed in claim 1, wherein the sealing mat (60) and flexible upstanding fins (68) are moulded as a unit.
3. 3. A channel section for use in an assembly as claimed in either claim 1 or 2.
4. 4. A channel section as claimed in claim 3 formed of a shaped metal sheet.
5. 5. A connecting block for use in an assembly as claimed in any one of claims 1 to 4.