TECHNICAL FIELD OF THE INVENTION

This invention relates to an odour trap for sanitary applications and waste fittings, especially wash-basins, sinks and the like.

BACKGROUND ART

Odour traps for domestic use in sanitary applications are well known. The basic and most common version comprises a flexible rubber house formed into an S-of P- shape, with water being trapped in the bend, in so doing preventing odours from escaping the drainage system and exiting back into the basin and hence the interior of the house.

Various attempted improvements to this system have been made, but the basic principle of operation is sound and the improvements tend to involve complex arrangements which are expensive.

Unfortunately the common P-or S-trap is aesthetically not very pleasing and because the formation of the bend in which the fluid seal located is lateral relative to the inlet to the trap, these arrangements take up a substantial amount of space which is a disadvantage where cupboards are located below the basin or sink. A further problem is that the materials of construction, as well as the ugly appearance make them unsuitable for external use as they perish easily upon exposure to ultraviolet light and heat. The lack of aesthetic appeal also typically requires that they be hidden within a bathroom vanity or kitchen cupboard.

It is therefore an object of this invention to provide an in-line odour trap which is aesthetically acceptable, does not take up significant space and is suitable for external use allowing multiple inputs, without being subject to excessive degradation by the elements. DISCLOSURE OF THE INVENTION

According to the invention, an in-line odour trap for sanitary applications comprises a hollow tubular member having an inlet and an exit centred about a common vertical axis, the inner wall of the tubular member including a radial barrier element, the free end of the barrier element being downwardly depending; and a diametrically oppositely disposed trough element, the free end of the barrier element terminating below the level of the rim of the trough element defining first and second compartments within the trough element, the compartments being in communication below the end of the barrier element; the barrier element and trough element forming a collection point for fluid, the collected fluid acting as a seal preventing odours from exiting the trap inlet.

In the preferred form of the invention, the radial barrier element has a first or mounting portion depending downwardly and obliquely toward the trough element. This mounting portion extends from one wall in an approximate semi-circular formation. This angle of the first portion is preferably 45 degrees. A range of angles is possible, although angles close to 90 degrees result in the trap not being self-cleaning. The free end depends downwardly, parallel to the walls of the tubular element. This has the effect of concentrating the flow rendering the trap self-cleaning.

The trough element preferably comprises an approximately U-shaped element integrally formed within the hollow tubular member, one arm of the U being free and the other being integrally formed with the inner wall of the hollow tubular member to provide a passage for flow into the base of the U, under the end of the barrier element and over the free arm of the U to the exit. According to SABS standards, the trough must permit a 10mm ball to pass through. When flow ceases, fluid is trapped in the base of the trough and a fluid seal is formed thereby preventing egress of odours back into the basin or sink to which the trap is attached.

The trap may include an inspection port in the vicinity of the level of the trough within the trap. In this form, the fixed arm of the U-shaped trough is located adjacent the lower edge of the inspection port. The trap preferably comprises a moulded polymeric material which results in a non-deformable product and in the preferred form, plumbing grade polyvinylchloride is used. Ultraviolet stabilizers may be incorporated to prevent degradation in traps used in exterior applications.

The dimensions of the trap may vary widely but is preferably dimensioned to attach to 40 mm and 50 mm fittings. In reality it may even engage fittings of 160 mm.

The trap may be mounted externally to accommodate washing machines and dishwashers and the design permits input from more than one source.

BRIEF DESCRIPTION OF THE DRAWINGS

The preferred embodiment of the invention is described below with reference to the accompanying drawings in which:

Figure 1 is an isometric top view of an odour trap according to the invention;

Figure 2 is an isometric bottom view of the trap of Figure 1 ;

Figure 3 is a sectional side view through the trap; and

Figure 4 is a similar view to Figure 3 showing the formation of a fluid seal in the trap.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the drawings, an in-line odour trap 10 comprises a hollow tubular member 12 which has an inlet 14 and an outlet 16 which lie on a common vertical axis. An inspection portion 18 is provided.

A short distance below the inlet, a barrier element 20 is integrally formed and extends from a short distance below the inlet on half of an inner wall of the hollow tubular element to form a substantially semi-circular barrier 22, the free end 24 of which is turned downwards, parallel to the walls of the tubular element. This free end bisects the U-shaped trough 26 and divides the trough into two interlinked compartments, channelling water flow through the trough, over the free wall 28 of the trough, to exit via the outlet 16.

When water ceases flowing, water remains pooled in the base 30 of the trough and provides a fluid seal 32 to prevent odours from exiting back via the inlet 14 as shown in Figure 4.