GB2165146A - Sink strainer - Google Patents

Abstract

A strainer for use in domestic sinks and the like is fabricated from a flexible material which will adapt to the shape of the sink base 3. Water drains through a central foraminate area 4 whose size is greater than that of the sink drainhole 2 and whose small foraminations 9 have a total cross-sectional area greater than the area of the drainhole 2. The lower surface of the strainer 1 is held off the sink base 3 by projections 8 which allow water to flow out of the sink through the whole of the perforated area 4. The strainer 1 optionally has a stopper 7, also in flexible material. <IMAGE>

Description

SPECIFICATION Sink strainer This invention relates to strainers for sinks and the like. These are placed in the sink or the like so that waste water, for example from dish washing, passes through perforations in the strainer before running away to the drain. The size of the perforations is such that when water passes through them most solid waste materials, such as tea leaves, which are present, accumulate on top of the strainer which can later be removed and cleaned.

Previously described strainers, for example that in GB 705,094, have been made of metal. This material has the disadvantage that the surface of the sink is often scratched by the strainer. There is the further disadvantage that, although the perforated area may be greater than the area of the plughole, since any part of this perforated area which is not directly over the drainhole is in immediate contact with the sink surface, the effective area for drainage is considerably reduced. Furthermore, a rigid strainer cannot be effectively fitted to sinks where the drainhole is in non-standard positions and in some modern types the hole is very near the wall or corner.

According to the present invention a strainer is provided which comprises a substantially flat flexible body which is foraminate over at least a central portion of its area and which has projections on one surface of the foraminate portion.

In the present invention the strainer is of a flexible, non abrasive, material. This allows it to be placed in a wider range of positions than if it were rigid and also to conform to sink (or the like) bases which are more than usually concave. To avoid the problem posed by clogging, the foraminate portion has on its undersurface projections which lift that surface from the underlying surface of the sink so that water passing through all foraminations in that portion can reach the drainhole.

These projections may be, for example, ribs or individual pips. To help strengthen the strainer its peripheral portion, beyond the foraminate portion, may be thicker than that portion, and may have a lower surface level with the lower ends of the projections.

To enable the sink to be stopped even while the strainer is in position, the strainer may have its own stopper, and may have means on its upper surface for positioning the stopper over the foraminate portion, for example a ridge (continuous or interrupted), forming a kerb around that area. The stopper may itself be flexible so as to adapt to curvature of the strainer when the latter is in position.

The foraminate portion may be normally planar or may in part be formed with a downwardly dished conformation, this part being intended to be placed directly above the drainhole.

The total cross-sectional area of the foraminations should be at least as great as that of a standard drainhole.

A strainer according to one embodiment is shown in the accompanying drawings where: Figure 1 shows a section through the strainer and its stopper and through the sink base; Figure 2 is a plan view of the strainer; Figure 3 is a cross section of another embodiment; and Figure 4 is a perspective view from above of the strainer and stopper.

The strainer 1 shown in Figures 1 and 4 is an essentially flat piece of plastic, rubber or other flexible material which covers a surface largerthan that of a standard drainhole 2. The strainer may be of any suitable outline, but the present embodiments are circular. A suitable maximum dimension is usually 10 cm and not more than 15 cm. The strainer is placed on the base 3 of a sink so that a central foramination portion 4 lies over the hole 2, and a peripheral part 5 rests on the base and is pressed downwardly by water above it when in use and holds the strainer 1 firmly in place over the drainhole 2. The peripheral part 5 is about 1 mm thick. The upper surface of the strainer has a ridge 6 around the portion 4 for positioning a stopper 7 whose area is equal to that inside the ridge. The stopper 7 is also of a flexible material.The area of the stopper may alternatively be less than the area inside the ridge so long as it is at least equal to that of the perforated area. The ridge 6 may also serve to facilitate removal of the strainer after use.

The portion 4 may be thinner than the peripheral part 5 but has on its undersurface projections 8 which may be, for example, ribs etc. The lower ends of the projections 8 are level with the lower surface of the part 5, so the projections hold the undersurface of the portion 4 off the sink base and the gaps between them act as drainage channels over the whole area of the part 4 while the part 5 rests on the sink 3 and at least substantially does not allow water to flow under it. The broken arrows indicate the routes which water can take out of the sink when the stopper is not present. The water passes through the foraminations 9 which have a diameter chosen to be between 3 and 7 mm. If the size of the foraminations 9 is too small then the water flow becomes inconveniently slow and the strainer 1 will clog easily.If they are too large then solid waste such as tea leaves will tend to pass through easily. Practical limits may be about 2 to 10 mm.

Figure 2 is a view of the strainer from above. The foraminations 9 in the part 4 which are shown as circular may, equally, be of any desired shape, as may the strainer itself. The perforations are distributed over the entire area 4. The area of the sink drainhole is indicated by the broken line 10.

Ideally, the total area of the foraminations should be equal to or greater than the area of the sink drainhole. This effect may be achieved by making the diameter of the strainer significantly larger than that of the drainhole or by increasing the number of holes or both. That portion of the strainer sitting over the drainhole may be a downwardly dished part of a spherical surface 11, as illustrated in Figure 3, where projections 8 are provided only on a portion of the undersurface of the part 4. In this way the total area of the foraminations may be further increased.

Figure 4 shows clearly the way in which the stopper7 is held by the ridge 6 of the strainer 1. The ridge 6 shown is interrupted in the preferred embodiment to facilitate water flow down the drainhole 2.

The stopper 7 has an upwardly projecting handle 12 at its centre to ease removal of the stopper 7 and a plurality of radial ribs 13 which give the floppy stopper 7 added strength.

As an alternative to having a thickened peripheral part 5 the peripheral part 5 and the central perforated area 4 may, as shown, be of substantially the same thickness, a step being provided around the circumference of the perforated area 4 so that the lower surface of the peripheral portion 5 is lower than the central perforated area 4 and is substantially level with the free ends of the projections.

Any of these embodiments may be constructed in a flexible material such as rubber or plastic and being quite thin, will be almost floppy. The strainer may then be positioned on an uneven sink surface or near a wall or corner. It does not matter if the centre ofthe foranimate area is not aligned with the drainhole. The stopper should also be similarly flexible for maximum adaptability.

Claims (12)

1. Strainer for a sink comprising a flexible body which is foraminate over at least a central portion of its area and has projections on one surface of the foraminate portion.

2. Strainer according to claim 1, having an outer peripheral part which is not foraminate and which has one surface coplanar with the extremities of the projections on the foraminate central portion.

3. Strainer according to claim 2 wherein the outer peripheral part has a thickness greater than that in those parts of the foraminate portion where there are no projections.

4. Strainer according to claim 2 or claim 3 wherein there is a step around the foraminate portion.

5. Strainer according to any of the preceding claims having a ridge around the foraminate portion and a stopper in flexible material, the stopper being adapted to fit inside the ridge.

6. Strainer according to any of the preceding claims wherein the foraminate portion is formed with an in-part dished conformation.

7. Strainer according to any of the preceding claims wherein the foraminations have a maximum dimension lying between 2 and 8 mm.

8. Strainer according to any ofthe preceding claims wherein the projections are in the form of ribs or pips.

9. Strainer according to any of the preceding claims wherein the body is substantially circular and has a diameter of between 10 and 15 cm.

10. Strainer substantially as herein described and with reference to the accompanying drawings.

11. Strainer according to any of the preceding claims which is placed over a sink drainhole so that the projections are in contact with the sink base, and so that part of the perforated area lies over the drain hole and in which the total cross-sectional area of the perforations is at least as great as that of the drainhole.

12. Strainer according to claim 11 wherein the sink base is non-planar.