GB2332095A

GB2332095A - Electrically heated water boiling vessels

Info

Publication number: GB2332095A
Application number: GB9725865A
Authority: GB
Inventors: Robert Andrew O'neill
Original assignee: Otter Controls Ltd
Current assignee: Otter Controls Ltd
Priority date: 1997-12-05
Filing date: 1997-12-05
Publication date: 1999-06-09
Anticipated expiration: 2017-12-05
Also published as: GB2332095B; GB2332095A9; GB9725865D0

Abstract

An electrically heated hot water jug has a steam sensor switch arranged to switch off the jug when water is boiled in the jug. The steam sensor switch is provided in a bottom part of the vessel and a steam conduit 4,6 is provided for conveying steam from the upper part of the vessel to the steam sensor switch. To avoid water entering the conduit if the vessel is tipped when being filled through its spout 7, the steam conduit extends to a location closely adjacent to the spout but shielded therefrom by a part 8 of the vessel lid 5. The steam conduit also acts as an effective chimney for ducting cooling air past the steam sensor switch after it has operated and been heated up by exposure to steam.

Description

wig 2332095 1 IMPROVEMENTS RELATING TO ELECTRICALLY HEATED WATER BOILING

VESSELS

Field of the Invention:

This invention concerns improvements relating to electrically heated water boiling vessels and, more particularly, relates to such vessels which are arranged to switch off automatically in response to the generation of steam when water boils in the vessel, there being a conduit built into the vessel for conveying the steam from the vessel interior to the location of a thermally-responsive switch which is commonly provided at or adjacent the bottom of the vessel, for example at the base of the handle of the vessel where there may also be provided a so-called dry boil control which is operative to switch off the vessel heating element if its temperature rises above a predetermined safe level, for example because of the vessel being switched on in a dry condition.

Back,zround of the Invention:

Electrically heated water boiling vessels of the kind abovementioned are well known. In early arrangements, as described for example in GB 1 384 527, the steam conduit was formed as a metal pipe integral with the vessel heating element which was formed as an immersion heating element and served to convey steam from the upper part of the vessel interior down 2 through the boiling water and out of the vessel via the heating element head portion. In more recent arrangements where the vessel body is formed as a plastics material moulding, the steam conduit is commonly formed integrally with the vessel body, but the principle of operation remains as of old.

It has been proposed to provide means associated with the steam conduit to inhibit the flow of water through the conduit, for example as the vessel is filled or if it is overfilled. Float valve arrangements have been proposed for this purpose and more recently, as disclosed in GB-A-2 295 725, GB-A-2 278 018 and GB-A-2 311 898, it has been proposed to provide a type of weir to direct water down a separate drain or a means for blocking the steam conduit when the vessel is switched off.

Obects and Summary of the Invention:

It is the principal object of the present invention to provide an efficient an inexpensive means for avoiding or at least substantially reducing the risk of water passing down the steam conduit of a vessel as aforesaid and accessing the electrical control system in the event that the vessel is tipped back with the spout uppermost when it is filled from a tap.

According to the present invention, the steam conduit of a vessel as aforesaid is extended to a location closely adjacent to the pouring spout but not such that water will enter the conduit either when the vessel is being emptied or when it is being filled via the spout.

3 In the case of a vessel provided with a removable lid, the invention proposes to provide on the underside of the vessel lid a conduit which, when the lid is closed, engages the top of the steam conduit in more or less a sealing manner. When the vessel is tipped back, full of water, then at the very worst only very little water can enter the steam duct, unless the vessel is so full that water is overflowing almost out of the spout which would clearly be visible to the user. The seal at the join between the conduit on the lid and the steam conduit need not be totally secure, since by restricting the gap the amount of water that can leak down the steam conduit is considerably limited and can readily be accommodated by water shedding features provided on the steam sensor control.

For a spout filling vessel with no removable lid, the conduit extension on the underside of the lid could be such as to make a much more watertight seal with the steam conduit or could be integral therewith.

The above and further features of the present invention are set forth in the appended claims and, together with advantages thereof, will be made more clear from consideration of the following description of an exemplary embodiment which is given with reference to the accompanying drawing.

Description of the Drawin2s:

Figure 1 is a side elevation view, partly in section, of an exemplary water boiling vessel embodying the present invention; and 4 Figure 2 is a perspective view of the underside of the lid of the vessel of Figure 1.

Detailed Description of the Embodiment:

Figure 1 is a partial cross-sectional view of a water boiling jug which, apart from the provision of a conduit (duct) extension on the underside of its lid is typical of such jugs. The electrical heating element and associated steam control and dry boil control of the jug are not shown but may be conventional.

The jug 1 comprises a moulded plastics body 2 having an integrally formed handle 3 and an integrally formed steam conduit 4 which is open at its upper end and communicates at its lower end with a chamber outside of the water containing volume of the jug which serves to house the electrical controls. The lid 5 of the jug is removable and has a conduit 6 provided on its underside as shown, the conduit 6 extending from a location at one end where it engages the upper end of the steam conduit 4 for communicating therewith to a location adjacent to the pouring spout (lip) 7 of the vessel, but isolated therefrom by a portion 8 of the lid 5 which dips down into the inside of the jug.

The conduit 6 on the underside of the lid furthermore has a small projecting rib 9 adapted to overlap the top of the steam conduit 4 to provide additional sealing.

The conduit extension 6 may be formed as an integral part of the lid 5, for example of moulded plastics material, or may be separately formed and secured to the lid by means of snap fits or by welding for example. The lid 5 may be a simple click-on lid or it may be hingedly connected to the jug body 2 so that it opens by tipping back.

It will be clear from Figure 1 that if the jug 1 is tipped back as it is being filled via the spout 7, the open end of the conduit 6 adjacent to the spout will remain above the water level in the jug even if the jug is overfilled to the extent that water can be seen in the spout. In normal circumstances, little or no water will access the steam conduit 4 when the jug is being filled. The safety of the appliance is thus enhanced.

The proposed lid duct has a further benefit beyond enhancing the safety of the appliance. With modern designs there is a tendency for little or no ventilation to be provided for cooling the steam control after boiling.

Ventilation holes are seen as unsafe, since steam may be ejected, and they spoil the styling of the appliance. The steam control is thus commonly enclosed in a hot chamber, with its thermal sensor close to the vessel wall, on the other side of which is a quantity of just boiled water. To ensure that the sensor cools rapidly to below the control reset temperature we have found that the duct described above tends to draw cool air in from beneath the vessel, acting as an efficient chimney ejecting the heat through the spout. The additional height of the duct outlet, and its closeness to the spout lead to this improvement in draught creation.

6 Having described the present invention by reference to a specific embodiment, it is to be appreciated that the embodiment is in all respects exemplary and that modifications and variations thereto will occur to the skilled reader without departure from the spirit and scope of the invention as set forth in the appended claims.

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Claims

CLAIMS:

1. An electrically heated water boiling vessel wherein a steam conduit is provided in the vessel for conveying steam generated in the vessel to a stearn Z sensor switch arranged to switch off the vessel, and wherein the end of the steam conduit that is open to the steam is located close to the spout of the vessel.

2. A vessel as claimed in claim 1 wherein the vessel has a handle on one side, a spout generally opposite the handle and a lid, and wherein the steam conduit extends within the vessel across the lid from a location close to the spout and down said one side of the vessel.

3. A vessel as claimed in claim 2 wherein the lid is removable or can be opened, and the conduit is formed in two parts, a first on the lid and a second on the vessel, which communicate with each other when the lid is in place or closed.

4. A vessel as claimed in claim 33 wherein sealing means are provided for substantially sealing the junction of said two conduit parts when the lid is in place or closed.

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5. A vessel as claimed in any of the preceding claims wherein the steam sensor switch is provided at or adjacent the bottom of the vessel.

6. A vessel as claimed in claim 5 wherein the steam conduit is arranged so as to serve, after the vessel has switched off, as a duct for cool air entering at or adjacent the bottom of the vessel, rising up the conduit and exiting from the open end thereof, said cool air serving to cool the steam sensor switch.

7. An -electrically heated water boiling vessel having a steam sensor switch arranged to switch off the vessel when water boils in the vessel, and wherein a duct is provided in the vessel with a lower end arranged for admitting cool air and an upper end for venting such air, said duct serving to deliver a cooling air flow to the region of the steam sensor switch after it has switched off the vessel.

8. A vessel as claimed in claim 7 wherein the steam sensor is provided at or adjacent the bottom of the vessel.

9. A vessel as claimed in claim 7 or 8 wherein the upper end of the duct is provided at or adjacent the spout opening of the vessel.

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10. An electrically heated water boiling vessel substantially as herein described with reference to the accompanying drawings.