GB2282523A - An electric kettle equipped with a filter - Google Patents

Abstract

The invention relates to an electric kettle comprising a receptacle (3) for liquid, a spout (15) located in the upper part of the receptacle (3), a filter (25) located inside the receptacle (3) through which the liquid can pass when it is poured out of the receptacle (3) through the pouring spout (15). The filter (25) is located above the recommended maximum liquid level N in the receptacle (3) when the kettle is in its normal heating position. It is formed by a thin rigid plate comprising perforations and disposed in the pouring spout (15) transversally to the flow of the liquid. The perforated plate is mounted without being water-tight on the inner wall of the pouring spout thanks to the presence of outlet perforations (31). This reduces the flow of liquid across the filter and thus encourages the deposition of scale which reduces the active surface of the filter and therefore the outlet flow rate. <IMAGE>

Description

AN ELECTRIC KETTLE EOUIPPED WITH A FILTER The present invention relates to an electric kettle comprising a receptacle for a liquid, an electric heating device for heating liquid placed in the receptacle, a pouring spout through which liquid can be poured out of the receptacle and a filter placed inside the receptacle so that when the liquid flows out through the pouring spout the liquid passes through the filter.

Electric kettles are normally used to boil water for the preparation of hot beverages such as tea or coffee. Particles of scale or fur appear depending on the hardness of the water, and some of these particles may become deposited on different parts of the kettle, and in particular on the parts of the kettle in contact with the water during the heating period.

The water, once heated, is poured out of the receptacle and entrains with it the particles of scale or fur which are in suspension in the water and also those particles which may form a type of scum on the surface of the heated water.

In existing types of electric kettles, the placing of a filter inside the receptacle is known so as to intercept the various particles of scale or fur which could escape therefrom. It has in particular been proposed to place inside the receptacle a fine-mesh filter which can be removed for cleaning to be performed.

This filter is normally in the form of a filter cloth supported by a frame which produces perfect water-tightness with the inner wall of the receptacle when the filter is placed in the operative position.

In this type of electric kettle, the permanent immersion of the filter during heating has the major drawback of exposing the said filter to a rapid deposition of scale or fur. It is therefore essential that the filter is able to-be cleaned very regularly, which implies that it has to be removable. This is especially the case when the mesh of the filter cloth is fine and when it also intercepts very small particles of scale or fur.

Furthermore the immersion of the filter during heating does not enable a metal filter to be used, bearing in mind the tendency of scale or fur to become fixed to every immersed metal component, without running the risk of very quickly blocking the through holes. If the through holes were made sufficiently large (with a diameter of roughly several millimetres) it would in this case reduce the risk of obstruction, but would then make the filter incapable of stopping even the largest particles of scale or fur.

Furthermore, the use of a filter cloth having a fine mesh does not normally enable an outlet flow rate of the liquid from the receptacle which meets the expectations of the user, who, for this reason, may then display some impatience.

Furthermore, the user may find tiresome the necessity of having to regularly remove the filter from the receptacle to clean it. However, the user cannot refrain from doing this otherwise the mesh will become obstructed, which occurs all the more quickly if the mesh is fine, making the outlet flow rate even slower.

The present invention aims to provide an electric kettle equipped with a filter which may remedy the disadvantages mentioned above. In particular, the present invention aims to avoid the presence of the filter having annoying consequences for the user such as, for example, the necessity of having to clean it very often.

According to the invention, the filter is located inside the receptacle so that it is positioned above the recommended maximum liquid level in the receptacle when the kettle is in its normal heating position.

The different characteristics of the invention have numerous advantages. It is thus possible to use a filter fixed permanently to the receptacle and therefore to avoid having to dismantle it to clean it, thus achieving an appreciable gain in time and increased ease of use for the user.

According to another characteristic of the invention, the filter is formed from a perforated rigid plate. It is thus much less fragile than conventional filter cloths and does not require a frame on its periphery nor a rib to support or strengthen it. The filter is simple to manufacture and inexpensive.

Moreover, as the plate does not dip into the liquid during the heating phase, it is not susceptible to the deposit of scale.

This therefore makes the use of a perforated metal plate for the filter possible.

According to another characteristic of the invention, the filter is disposed in the pouring spout transversally to the flow of the liquid. The peripheral region of the filter which is adjacent to the inner wall of the pouring spout is mounted without being water-tight against the inner wall. This lack of water-tightness of the assembly of the plate on the inner wall of the pouring spout enables the liquid to flow through outlet perforations in the plate without having to pass around a solid space (weld, frame surrounding a filter cloth, etc.).

In the contact zone of the filter and the inner wall of the spout, this reduces the component of the flow of liquid parallel to the face of the filter. This component has an adverse effect on the general flow of the liquid in this zone and benefits the rapid formation of a deposit of scale which reduces the active surface of the filter and therefore the outlet flow rate. It will therefore be understood that such a characteristic of the invention is particularly advantageous when the filter is fixed permanently to the kettle.

Furthermore, the position of the filter in the upper part of the receptacle enables, if necessary, easy access for its cleaning and also simplifies assembly at the time of manufacture.

According to another characteristic of the invention, the perforated plate which forms the filter may be coated with an anti-corrosive coating. In the event of the plate itself being made of metal, it is then possible to make it, if desired, from a rigid and economical material which is likely to corrode, since the metal may then be protected by an anticorrosive or non-oxidising coating such as, for example, gold.

The various characteristics and also the advantages of the invention will furthermore become apparent from the following description which is made with reference to the attached drawings, which illustrate by way of a non-restrictive example how the invention can be performed and in which: - Figure 1 represents a vertical sectional view of a possible embodiment of an electric kettle equipped with a filter according to the invention; - Figure 2 represents an enlargement of the pouring spout of the electric kettle in Figure 1, without the filter; - Figure 3 represents a sectional view along line A-A of Figure 2; - Figure 4 represents a plan view of the pouring spout according to Figure 2; - Figure 5 represents in elevation a front view of the filter;; - Figure 6 represents an enlargement of a part of the peripheral region of the filter showing the arrangement of the perforations.

According to Figure 1, the electric kettle comprises a housing 1 closed by a lid 2. The housing provides a receptacle 3 which is intended to contain water which can be brought to boiling point by an electric heating resistor 4 and comprises a hollow handle 5 having a grip part 6 and also a base 7 integral with an outer wall 8 of the receptacle 3. Components 1, 2, 3 and 5 may advantageously be made from plastic material.

The resistor 4 is electrically controlled by a heat-sensitive switch 9 which is disposed outside the receptacle 3 in the lower region of the housing 1. The switch 9 is sensitive to the temperature of the steam directed through a conduit 10 which extends parallel to the outer wall 8 of the receptacle 3 from the upper region of the housing 1 to the switch 9 and the outlet 11 for which is situated above the recommended maximum water level N in the receptacle 3.

The electric kettle comprises an electricity power unit 12 comprising a control mechanism 13 which can be moved between an "on" position and an "off" position by manually operating a press button 14, and designed so as to be brought into its off position when the steam directed into the conduit 10 sufficiently heats the heat-sensitive switch 9 to activate it.

The press button 14 is disposed in an aperture provided in the lower part of the handle 5.

According to the invention, a filter 25 is located above the recommended maximum liquid level N in the receptacle 3 when the kettle is in its normal heating position.

The receptacle 3 becomes wider at a place on its upper part so as to form a pouring spout 15. Projections 16, 16', 17, 17', 18, 18', 19, 19' and 20 protrude from the inner wall of the spout 15 in order to keep the filter 25 in place and by alternately making contact with the faces A and B (see Figures 2, 3 and 4).

The two upper projections 16 and 16' are equipped with holes 21, 21' provided to receive permanently two corresponding male parts (not shown on the Figures) situated at the ends (22a) and (22b) of the strip 22 fixed to the upper edge of the filter 25 (see Figure 5).

The filter 25 is formed by a thin rigid perforated plate 23 having a thickness of roughly 0.2 mm, consistent with the spear-shaped profile of the inner wall of the pouring spout 15 and on the upper edge of which a curved strip 22 made of plastic material extends. The strip 22 is fixed to the plate 23 in a manner known per se and not shown, for example, by insert moulding or latching. During assembly the plate 23 equipped with its strip 22 is inserted from above into the pouring spout of the electric kettle until the lower edge 24 of the plate 23 comes to abut the lower inner wall of the pouring spout 15 at the level of projection 20. The male parts mentioned above which protrude perpendicular to the plane of Figure 5 are then engaged in the corresponding holes 21, 21'.

It would also be possible to fix the strip 22 to the inner wall of the pouring spout 15 by other means, for example by welding.

The plate 23 comprises several perforations 30 (see Figure 6) having a diameter of roughly 0.5 mm which are arranged in groups of five (staggered) so that the distance between the axes of each perforation is roughly 1.0 mm. Considering the size and the distribution of the perforations, the plate may intercept a large proportion of the particles of scale or fur present in the heated water without substantially reducing the flow rate.

The plate 23 is preferably planar and made from metal but it may also be made from moulded plastic material.

The plate 23 may be coated with an anti-corrosive coating suitable for food use having a golden or silvery appearance.

Such a coating makes the plate 23 non-oxidising/non-scaling and guarantees perfect hygiene for the user.

It can be easily seen from Figure 6 that the plate 23 has outlet perforations 31 in its peripheral region. These outlet perforations are advantageously made when the plate 23 is punched from a larger perforated plate. These outlet perforations 31 enable water to flow under good conditions into this peripheral region thus greatly reducing the component of the flow of water parallel to the face B of the filter 25. These good conditions of flow effectively protect against the formation of a rapid deposit of scale or fur in this region.

Thanks to the invention, the filter 25, once it has been fixed in the receptacle 3, is always situated above the recommended maximum water level N when the electric kettle is its normal heating position. This arrangement ensures that the plate 23 is never immersed in the water during the heating period and especially during the boiling phase, thus avoiding scale or other sediment being able to become deposited there and blocking the perforations.

Claims (11)

Claims

1. An electric kettle comprising a receptacle for a liquid, an electric heating device for heating liquid placed in the receptacle, a pouring spout through which the liquid can be poured out of the receptacle and a filter placed inside the receptacle so that when the liquid flows out through the spout the liquid has to pass through the filter, the filter being located above the recommended maximum liquid level in the receptacle when the kettle is in its normal heating position.

2. An electric kettle according to Claim 1, wherein the filter is permanently fixed inside the receptacle.

3. An electric kettle according to Claim 1 or 2, wherein the filter is formed from a thin rigid plate having perforations and disposed in the pouring spout transversally to the flow of the liquid and in which the peripheral region of the filter which is adjacent to the inner wall of the spout is mounted without being water-tight against the said internal wall.

4. An electric kettle according to Claim 3, wherein the plate is retained inside the pouring spout by projections protruding from the inner wall of the pouring spout and alternately contacting opposite faces of the plate.

5. An electric kettle according to Claim 3 or 4, wherein the perforations have a diameter of roughly 0.5 mm and are disposed in groups of five so that the distance between the axes of each perforati This is roughly 1.0 mm.

6. An electric kettle according to Claims 3, 4 or 5, wherein at least some of the perforations which are positioned in the peripheral region of the plate are truncated by the edge of the plate.

7. An electric kettle according to any one of Claims 3 to 6, wherein the upper edge of the plate carries a strip, the ends of which are fixed to the inner wall of the pouring spout.

8. An electric kettle according to any one of Claims 3 to 7, wherein the plate is made of metal.

9. An electric kettle according to any one of Claims 3 to 8, wherein the plate is planar.

10. An electric kettle according to any one of Claims 3 to 9, wherein the plate is coated with an anti-corrosive metal coating.

Amendments to the claims have been filed as follows 7. An electric kettle according to any one of Claims 3 to 6, wherein the upper edge of the plate carries a strip, the ends of which are fixed to the inner wall of the pouring spout.

8. An electric kettle according to any one of Claims 3 to 7, wherein the plate is made of metal.

9. An electric kettle according to any one of Claims 3 to 8, wherein the plate is planar.

10. An electric kettle according to any one of Claims 3 to 9, wherein the plate is coated with an anti-corrosive metal coating.

11. An electric kettle substantially as hereinbefore described with reference to, and as illustrated in, any one of the accompanying drawings.