GB2429216A

GB2429216A - Floor drain with removable trap

Info

Publication number: GB2429216A
Application number: GB0524671A
Authority: GB
Inventors: Andrew Reginald Lee
Original assignee: Alumasc Group PLC
Current assignee: Alumasc Group PLC
Priority date: 2005-08-18
Filing date: 2005-12-02
Publication date: 2007-02-21
Anticipated expiration: 2025-12-02
Also published as: GB0524671D0; GB0516982D0; GB2429216B

Abstract

A floor drain 10 comprising a removable water seal 68, and a convergent downwardly directed passageway 60 configured to establish enhanced water flow adjacent to or through the water seal, whereby the flow capacity of the drain is increased. The passageway may comprise a frustoconical middle portion 64. In one embodiment the floor drain has a removable trap component 52 incorporating the water seal 68 and the passageway 60. A height adjustable grate assembly 30 may also be comprised.

Description

FLOOR DRAIN

Field of the Invention

The present invention relates to floor drainage systems, and more particularly to floor drains themselves.

State of the Art A type of height adjustable floor drain culTently on the market comprises a grate assembly consisting of a grate secured in a bezel and a tubular throat depending from the bezel. The throat is either screw threaded or telescopically fitted to a drain body assembly situated below floor level, e.g. cast into a concrete sub-floor. Height adjustment of the throat element to align the bezel with the firnshed floor surface can be either by the screw thread or by sliding telescopically through an "0" ring seal. This drain may be trapped or untrapped.

Foul air traps generally consist of three types: a self contained dip tube and cup, a dip tube is within a sump and a sump with a dividing air baffle.

In one variant of this height adjustable floor drain, a water seal is provided by a dip tube fitted inside the throat having an upper funnel portion receivable in the bezel. The dip tube extends into a sump formed in the bottom of the drain and is cut to match the adjusted height of the grate assembly. If the dip tube is cut too short then the water seal is absent or inadequate. However, if the dip tube is cut too long then this creates seating problems for the grate assembly. Thus, the length of the dip tube is crucial and requires a level of skill and understanding for correct installation.

The throat slides through a central aperture in a clamping collar forming part of the body assembly. The clamping collar is secured to an upper frustoconical flange on the drain body, to seal and secure a damp proof membrane or bituminous layer to the drain body.

Because the throat is of relatively restricted diameter and the outlet opening is provided to one side at the upper end of the drain body, rodding access through the drain body is difficult. This is particularly the case where a long throat is required in order to accommodate thicker finishing structures built up from the sub-floor, as may he dictated for example by modern insulation requirements. The sump in the bottom of the drain body is pennanently mstalled and may he prone to sludge etc. deposition. Access to the sump for cleaning purposes is similarly restricted. If the throat is excessively long for a given installation, so that it extends into the drain body well beyond the clamp ring, these access problems are exacerbated. Enlarging the throat diameter for improved access requires a correspondingly enlarged drain body, adding to cost and making the floor drain unsuitable for installation in restricted spaces.

In untrapped floor drains of the above kind providing a height adjustable grate assembly, the trap element is omitted and the outlet opening is positioned at the bottom of the drain body so as to eliminate the sump. Installation and access problems are thus reduced. However, because different drain body styles are required for trapped and untrapped installations, stock inventory is increased throughout the manufacturing and supply chain, adding to costs.

As noted above, self-contained foul air traps are also available for fitment into standard untrapped outlets providing a similar water seal to a trapped outlet. Whilst current untrapped outlets provide adequate flow rates, these modular water seals restrict the outlet is flow area, creating a bottleneck in the drainage system that reduces the flow rate to possibly

unacceptable levels.

EPO 124888 concerns a floor drain having a body assembly which includes a removable foul air trap or siphon insert. The drain body forms a relatively large diameter pot which accommodates the siphon insert. A grate may be fitted to an upper opening in the drain body or at the upper end of an extension piece fitted to the opening. Both the opening and the extension piece are of a similarly large diameter to the pot, to permit removal of the siphon insert, if required, e.g. for cleaning purposes after the floor drain has been installed.

The overall assembly may therefhre be relatively bulky.

EP1329562 relates to a floor drain having an inlet giating beneath which is a tapering funnel leading to a short vertical pipe. This fits into a SU suspended in the drain body, with outlet apertures near the top. Water passes through an annular space between the outside of the sump and the inside of the drain body. The funnel and short vertical pipe represent a flow restriction. A similar sink or floor drain trap comprising an outer cup detachably connected to a dip tube is disclosed in GB2O 12333.

Roof drainage outlets are known that induce siphonic or otherwise enhanced water flows in the pipcwork to which they arc connected This increases the flow capacity of the entire drainage system and thereby reduces the number of outlets required to drain a given roof area. Siphonic flow is not the same as a "siphon" in the sense of a foul air trap as discussed for example in EPO 124888 above. Siphonic flow instead relies on a column of falling water to generate a pressure drop which results in water being drawn into the roof outlets under the influence of atmospheric pressure, at an enhanced flow rate. The column of falling water is generated by ensuring that under design flow conditions the pipework to which the roof outlets are connected is substantially filled with water. The pipework systems therefore require careful design and installation in order to function effectively. For these reasons, air breaks are sometimes deliberately introduced into the pipewoi-k, so that only part of the system immediately downstream of the roof outlets draws down under design flow conditions: see e.g. DE4 141096.

To prevent possible damage from high flow rates and]arge pressure differences, full-bore flow in underground drains connected to public sewers is generally not permitted. Pipes are adequately sized, falls (gradients) are controlled and ventilation is provided to ensure that negative pressure flows do not become established in the underground pipework.

W09 1/1 1 566 concerns a floor drain in which a drainage bowl has an upwardly facing inlet opening and an outlet which comprises slots or passageways each with a substantially vertical portion with constant cross-section, designed to fill with water to produce a suction effect and enhanced flow. In the vanous illustrated embodiments, the passageway vertical portions arc defined between the bowl inner side wall and an internal member, in an annular arrangement. The outside diameter of the bowl side wall defining the passage vertical portions is therefore relatively large.

The present applicant has realised that a hydraulically efficient floor drain is possible which can be advantageous in improving the flow capacity and cleaning access in a trapped floor drain of a compact size, even if siphonic flow is not acceptable in any connected underground pipework.

Summary of the Invention

Accordingly, the present invention provides a floor (Irain comprising a downwardly extending passageway having an open lower end submerged in use in a body of water held within a reservoir within the drain to form a water seal, an inlet at the upper end of the passageway and an elongate convergent portion of the passageway between the inlet and the water seal which forn-is a driving head space to induce enhanced flow through the passageway. In preferred embodiments, the upper end of the passageway is large enough to handle the design flow rate without completely filling with water. The falling water accelerates in the convergent passageway, so that a sufficiently high flow rate is maintained throughout. In this way a compact, hydraulically efficient floor drain may be produced, which is readily installable even in small spaces. The lower end of the passageway may completely fill with water, particularly at higher flow rates. However, the water seal can provide a discontinuity in the available flow area that counteracts any tendency to establish full bore flow and prevents the generation of negative pressure downstream of the drain.

Because the lower end of the passageway has a smaller cross-section than the upper end, the cross-sectional area of the reservoir can be similar to that of the upper end of the passageway, preferably no more than 1.4 times that of the upper end of the passageway, more preferably no more than 1.2 times that of the upper end of the passageway, most Is preferably no more than I. 1 times that of the upper end of the assageway. so that the water seal is itself compact.

Preferably the drain comprises a removable trap component incorporating the water seal and preferably also the passageway. Inclusion or removal of the trap component allows the drain to be configured either as a trapped or as an untrapped drain, using a single standard set of parts. When configured as a trapped drain, temporary removal of the trap component allows good access to the drain interior, for example for cleaning or rodding purposes.

Particularly space efficient drain configurations are obtainable because enhanced flow capacity is induced in or by the convergent passageway. This helps to compensate for the reduction in the available flow area caused by the presence of the water seal. When the trap component is removed, the available flow area is correspondingly increased, so that enhanced flow may no longer he required in order to sustain acceptable flow rates through the drain.

The removable trap component may be supported in a height adjustable grate assembly. in this way a height adjustable floor drain is obtained which does not rely on a fixed sunip for the provision of a foul air trap. so a\oiding the difficulties of access and sludge accumulation discussed above The grate assembly may comprise a grate having drainage apertures (slots or holes) having radiussed inlets and/or outlets, for improved flow characteristics.

The grate assembly may comprise a cylindrical throat telescopically adjustable with respect to drain lower parts, including an outlet pipe connection. The removable trap component may be concentrically supported in the throat. This again provides a space efficient configuration. With the trap component removed, the throat opening may be sufficiently large for hand access to the drain interior, e.g. for cleaning purposes. The removable component preferably extends along the entire length of the throat so as to maximise the length of passageway available to establish and maintain enhanced flow capacity. Best results are obtained with a gradual taper. The grate assembly preferably incorporates sufficient adjustment for most floor thicknesses, for example by making the throat long enough.

The throat may be formed from a length of tube, with an internal threaded connection to a bezel at its upper end. The corresponding internal surface of the bezel formS a smooth surface for sealing engagement by the removable trap component.

For enhanced hydraulic efficiency, the removable trap component preferably has a smoothly radiussed inlet. For example, the inlet may be trumpet shaped.

The vertical distance through the passageway from the seal water level to the finished floor level may be at least 1 50mm, preferably at least 160mm, more preferably at least 1 70mm, so that an adequate height of water column is available to establish and maintain the enhanced flow. The removable trap component may comprise a cup shaped receptacle positioned over the passageway lower end. Used together with a convergent passageway, the cup outflow area (between its rim and the corresponding cross-section of the passageway) is enlarged, for a given cup rim crosssectional area. The convergent passageway therefore also reduces the required cup cross section. resulting in a more compact trap component configuration for a given flow rate.

The floor drain may comprise a body with a base comprising a downwardly directed pipcwork connection. Alternatively, the drain may comprise a body with a base comprising a lateral pipework connection or a base with a connection at an angle to the vertical. In either case, the problem of sludge accumulation is reduced or eliminated, as there is no fixed sump. Rodding access to the attached pipework is also improved.

The removable trap component is of sufficiently small diameter to fit within a 110 mm drain pipe, yet is hydraulically efficient, such that flow is not significantly impeded. The removable trap component therefbre may be used to convert an untrapped drain to a trapped drain. For example, the throat tube described above may be connected directly to a drainage pipework system without the drain body and clamping ring, sirnpli'ing and reducing the number of components required, e.g. where height adjustment and/or a seal to an impermeable membrane within the floor structure is unnecessary. Accordingly, the invention also provides a removable trap for a floor drain, comprising a downwardly extending passageway having an open lower end submerged in use in a body of water held within a reservoir within the trap to form a water seal, an inlet at the upper end of the Is passageway and an elongate convergent portion of the passageway between the inlet and the water seal which forms a driving head space to induce enhanced flow through the passageway.

Where fire protection is required, the throat tube can be made of a suitable fire resistant material, such as cast iron.

Further features and aspects of the invention will be apparent from the following description of illustrative embodiments, made with reference to the drawings.

Brief Description of the Drawings

Figure 1 shows a floor drain embodying the invention and having a horizontal pipework connection spigot; Figure 2 shows a variant of the floor drain of Figure 1, having a vertical spigot, and Figure 3 shows a further variant.

Detailed Description

The floor drain 1 0 shown in Figure 1 comprises a body assembly 12 consisting of a east aluminium body 14 and a clamping collar 1 6. The clamping collar 1 6 ensures a watertight seal between the flooring damp proof membrane or bitumastic layer and the drain body.

The membrane (not shown) is held against the drain body by the clamping collar and sealed by compression via three retaining bolts 18 (only one shown) ovcr an 0' ring 20 set in a groove in the drain body. The collar also incorporates an airtight bung 22 which can be removed, thus creating a weep hole for the relief of screed saturation especially in a tiled floor.

The floor drain 10 ftirther comprises a grate assembly 30, consisting of a machined grate 32 attached to a bezel 34 by screws 36. The bezel is attached via a threaded connection 38 to an adjustable smooth sliding throat 40. The threaded connection is to the inside of the throat leaving a smooth sealing area 42 inside the bezel for sealed reception of the trap assembly as discussed below. The drain body assembly 12 telescopically receives the grate assembly 30 by passing the smooth sliding throat 40 through a seal ring 44 mounted in the central aperture of the clamping collar 1 6. Any suitable form of seal ring 44 can be used: for example an "0" ring as shown in Figure 2. The throat is therefore conveniently formed i from a length of 1TPVC pipe. The throat is vertically adjustable relative to the collar to allow for different floor thicknesses above the body assembly 12. The grate assembly 30 is supported in the surrounding floor structure (not shown), e.g. cast into a floor screed. As shown in Figure 1, the grate assembly 30 is in its lowest possible position relative to the body assembly 12. In this position, the lower rim of the throat 40 is level with the apex 46 of a horizontal outlet spigot 48 extending from the bottom of the body 14. Longer throat tubes 40, where used, are prevented from intruding further into the body 14 and obstructing the outlet 48, by one or more fins or bosses 50 which protrude from the inside of the body 14.

The removable trap component comprises an assembly 52 that sits inside the grate assembly and is scaled against the bezel inner surface 42 by a suitable seal 54. The trap assembly 52 thus moves together with the grate assembly 30, and relative to the body assembly 12, on adjustment of the grate assembly 30. The trap assembly 52 has a smoothly radiussed "trumpet" like inlet profile 56, continuous with the adjacent bezel surface for increased hydraulic efficiency. A pair of finger grips 58 extends outwardly from this profile, to allow more ready removal of the trap assembly when required. The trap assembly provides a head space inside a vertical passageway 60 having an upper straight or cylindrical portion 62, a tapered or frustoconical middle portion 64, and a lower straight or cylindrical dip tube end 66. To provide maximum dn\ ing head, the removable trap component extends beyond the length of the throat 40 and just clear of the bottom of the body 14 when the grate assembly is in its lowest position.

Towards the lower end of the passageway 60, just below the tapered profile 64, is attached a cup 68 which forms a reservoir for a water seal. This receives the dip tube end 66. The rim of the cup 68 has hooked profiled ears' 70 for engagement with similar but oppositely bent hooks 72 extending from the outside of the passageway 60. The ears and hooks 70, 72 may be disengaged to allow removal of the cup 68 for cleaning. Once fitted, the walls of the cup 68 surround the lower dip tube end 66 to form an annulus. Water which enters the grate assembly 30 flows through the passageway 60 and out through the top of the annulus. When flow has ceased, the cup remains full of water. A water seal is thus formed between the dip tube end 66 and the cup 68. In this embodiment, the trap assembly 52 extends upwardly from the rim of the cup 68 to the top of the grate 32 distance of about 1 71 mm, to provide a corresponding driving head.

Water flowing over the rim of the cup encounters a sudden increase in available flow area, which acts as a siphon break, counteracting any tendency for full bore flow to become established in the outlet spigot.

A temporary stopper (not shown) is fitted in the clamp ring 1 6, inside the seal ring 44, to prevent debris e.g. cement falling into the body assembly prior to fitment of the grate assembly 30. After fitment of the grate assembly, the whole trap assembly 52 is removable for: a) cleaning purposes such as rodding the drain or cleaning debris from the cup 68 and h) conversion of floor drain from trapped to untrapped, or vice versa.

The underside of the horizontal drain body 14 is provided with a stabilising foot 74 allowing it to stand upright on a horizontal surface for display purposes, despite the curved profile of the spigot 48.

The floor dram 100 shown in Figure 2 is similar to the floor drain 1 0 of Figure 1, with the following differences. The spigot 148 shown is vertical and thus water flowing out of the water trap ia the annulus enters a vertical outlet rather than a horizontal outlet. The seal ring 44 is a simple "0" ring seal received in a groove provided in the clamping ring 1 66, as previously noted. Other spigot configurations and detail changes are possible and the invention is not limited to the specific embodiments shown in the drawings. In the UK, nominal pipe IDs for foul water drains are 110 and 150 mm, and the spigots 48, 148 may be sized correspondingly. However, other dimensions are possible, such as 75 mm ID, or other sizes, for example depending upon the size of the connecting pipework. Optionally, whatever the form of the spigot 48, sockets or other connections for receiving inlet pipes may be provided, communicating with the interior of the drain body 14, 114. The bore of such a connection is indicated by broken lines 76 in Figures 1 and 2, hut the connection may of course be of any suitable form or in any desired position. A radially inwardly extending stop or shoulder 82 may be provided at the inner end of the bore 76, to stop connected pipe ends from intruding into the interior of the body 14, 114. Ribs may be provided on the exterior of the body 14, 114 which help to key it into a concrete subfloor or other surrounding structure. Radial nbs 78 (shown in section) and circumferential ribs 80 are shown in the drawings.

In the embodiment shown in Figure 3, the throat component is formed from a length of pipe 240 whose lower end is directly connected to the drainage pipework system 252 by any suitable coupling, for example of the elastomeric sleeve and split clamping ring type as shown. The upper end of the throat component 240 is threadedly connected to a bezel 234 of a grate assembly 230, in similar manner to the previously described embodiments. The bezel 234 has a shallow frustoconical flange 236 which co-operates with a clamping ring 216 to sealingly secure a vinyl or similar impermeable flexible sheet floor covering 220 to the grate assembly 230. The clamp ring 216 is secured to the bezel 234 by circumferentially spaced screws 21 8 (only one shown), and surrounds a grate 232 also secured to the bezel 234, by screws 236. With this arrangement, there is no need to seal the drain fitting to an impermeable membrane within the floor structure, so the drain body 14 and clamping collar 16 are unnecessary. Height adjustment, if needed, can he achieved by adjusting the height of the connecting pipework 252 or by cutting the throat 240 to length. Where fire resistance is required, the throat pipe 240 is made from a suitably incombustible and relatively high melting point material such as cast iron. The bezel and grate may be made from any suitable materials such as cast nickel bronze, stainless steel or aluminium. The removable trap component 52 is sealingly received in the bezel 234 and is otherwise similar to the trap components of the previously described embodiments.

The features of the various embodiments may be used in different combinations as appropriate. For example, the bezel of Fig. 3 may be used with the throat and drain bodies of Figs. I or 2 or vice versa. Numerous other modifications will be readily apparent, within the scope of the claims.

Claims

Claims 1. A floor drain comprising a downwardly extending passageway

having an open lower end submerged in use in a body of water held within a reservoir within the drain to form a water seal, an inlet at the upper end of the passageway and an elongate convergent portion of the passageway between the inlet and the water seal which forms a driving head space to induce enhanced flow through the passageway.
2. A floor drain as defined in claim I, which comprises a removable trap component incorporating the water seal.
3. A floor drain as defined in claim 2 in which the removable trap component incorporates the passageway.
4. A floor drain as defined in claim 2 or 3 in which the removable trap component is supported in a grate assembly comprising a bezel joined to a tubular throat.
5. A floor drain as defined in claim 4 in which the removable trap component extends along the entire length of the throat.
6. A floor drain as defined in claim 5 in which an internal surface of the bezel is sealingly engaged by the removable trap component.
7. A floor drain as defined in any of claims 4 to 6 in which the grate assembly and passageway are moveable together in relation to a drain body assembly.
8. A floor drain as defined in any preceding claim comprising a body with a base comprising a downwardly directed pipcwork connection.
9. A floor (Irain as defined in any of claims I to 7 comprising a body vith a base comprising a lateral pipework connection.
10. A floor drain as defined in any of claims 1 to 7 comprising a body and a pipework connection extending from the bottom of the body at an angle to the vertical.

10. A floor drain as defined in any of claims I to 7 comprising a body with a base comprising a pipework connection extending at an angle to the vertical.

11. A removable trap for a floor drain, comprising a downwardly extending passageway having an open lower end submerged in use in a body of water held within a reservoir within the trap to form a water seal, an inlet at the upper end of the passageway and an elongate convergent portion of the passageway between the inlet and the water seal which forms a driving head space to induce enhanced flow through the passageway.

12. A floor drain as defined in any of claims I - 10, or a removable trap as defined in claim 11, in which the elongate convergent portion of the passageway comprises a frustoconical portion.

13. A floor drain as defined in any of claims I - 10 or 12, or a removable trap as defined in claim 11 or 12 in which the inlet is smoothly radiussed.

14. A floor drain as defined in any of claims 1 - 10 or 12 or 13, or a removable trap as defined in any of claims I I - 1 3, in which the crosssectional area of the reservoir is similar to that of the upper end of the passageway.

15. A floor drain or removable trap as defined in claim 14, in which the cross-sectional area of the reservoir is no more than 1.4 times that of the upper end of the passageway.

16. A floor drain or removable trap as defined in claim 14, in which the cross-sectional area of the reservoir is no more than 1.2 times that of the upper end of the passageway 17. A floor drain or removable trap as defined in claim 14, in which the cross-sectional area of the reservoir is no more than 1.1 times that of the upper end of the passageway.

18. A floor drain as defined in any of claims 1 - 10 or 12 - 17, or a removable trap as defined in any of claims II - 1 7, in which the head space from the seal water level to the so finished floor level is at least I 50mm 1 9. A floor drain as defined in any of claims I 1 0 or 1 2 - 1 7, or a removable trap as defined in any of claims 11 -- 1 7, in which the head space from the seal water level to the finished floor level is at least 160mm 1-, 1.D 20. A floor drain as defined in any of claims I or 12- 17, or a removable trap as defined in any of claims 11 - 17, in which the head space from the seal water level to the finished floor level is at least 1 70mm.

21. A floor drain as defined in any of claims 1 to 10 or 12 to 20, or a removable trap as defined in any of claims 11 to 20, comprising a cup shaped receptacle positioned over the passageway lower end.

22. A floor drain substantially as described with reference to or as shown in the drawings.

23. A removable drain trap substantially as described with reference to or as shown in the drawings.

BP-09-0587 Amendments to the claims have been filed as follows Claims 1. A floor drain comprising a downwardly extending passageway having an open lower end submerged in use in a body of water held within a reservoir within the drain to form a water seal, an inlet at the upper end of the passageway and an elongate convergent portion of the passageway between the inlet and the water seal which forms a driving head space to induce enhanced flow through the passageway.

2. A floor drain as defined in claim 1, which comprises a removable trap component incorporating the water seal.

3. A floor drain as defined in claim 2 in which the removable trap component incorporates the passageway.

4. A floor drain as defined in claim 2 or 3 in which the removable trap component is supported in a grate assembly comprising a bezel joined to a tubular throat.

5. A floor drain as defined in claim 4 in which the removable trap component extends along the entire length of the throat.

6. A floor drain as defined in claim 5 in which an internal surface of the bezel is sealingly engaged by the removable trap component.

7. A floor drain as defined in any of claims 4 to 6 in which the grate assembly and passageway are moveable together in relation to a drain body assembly.

8. A floor drain as defined in any preceding claim comprising a body and a downwardly directed pipework connection extending from the bottom of the body.

9. A floor drain as defined in any of claims 1 to 7 comprising a body and a lateral pipework connection extending from the bottom of the body.