GB2365319A

GB2365319A - Venting steam from boiling sensor of kettle

Info

Publication number: GB2365319A
Application number: GB0019402A
Authority: GB
Inventors: Peter Hallam Wright; Antonio Martin Gaeta
Original assignee: Otter Controls Ltd
Current assignee: Otter Controls Ltd
Priority date: 2000-08-07
Filing date: 2000-08-07
Publication date: 2002-02-20
Anticipated expiration: 2020-08-07
Also published as: GB0019402D0; GB2365319B; WO2002011590A1; AU2001276524A1

Abstract

In an electrically-heated water-boiling vessel having a steam duct 6 for conveying steam to a boiling sensor mounted in a bottom compartment of the vessel, means 13 are provided for venting exhaust steam laterally outwardly of the vessel. This avoids formation of a pool of condensed steam as may occur with downwardly-directed vents. Means 13 may be slotted apertures. The compartment may be beneath a planar heating element 3. The vessel may be a cordless appliance mountable on a base at any orientation throughout 360 degrees.

Description

2365319 IMPROVEMENTS RELATING TO LIQUID HEATING VESSELS

Field of the Invention:

This invention concerns improvements relating to liquid heating vessels and more particularly concerns water boiling vessels, such as kettles and jugs for example, which incorporate a steam or boil control arranged to be responsive to the generation of steam when water boils in the vessel to switch off or reduce the power supplied to an electric heating element of the vessel.

Backffound of the Invention:

The provision of steam controls in electric kettles and hot water jugs is well known. Fairly recently, however, the use of planar heating elements in such appliances has become commonplace, with the planar heating element being either of the underfloor type comprising a metal plate having a sheathed heating element affixed to the underside thereof or of the thick film type comprising a metal substrate having a thick film heater track on the underside thereof. Additionally, cordless appliances, comprising a vessel proper and a base upon which the vessel has to be seated in order for power to be supplied through the base to the vessel heating element, have become popular.

Cordless water heating appliances provided with planar heating elements and with steam controls have developed such that the preferred construction has 2 the steam control located in a compartment of the vessel proper underneath the planar heating element, such compartment also serving to accommodate an element protector control designed to switch off the power supply to the vessel heating element in the event of the heating element temperature rising above a predetermined safe level.

Disclosed in GB-A-2 339 088 is an element protector control which we manufacture and sell as our X4 series control, and disclosed in GB-A-2 331 848 is a steam. control which we manufacture and sell as our Z5 steam control. The X4 element protector control is designed to be usable with the Z5 steam control which simply connects onto terminals provided on the side of the X4 control. The X4/Z5 combination is designed for use with cordless kettles and hot water jugs and the X4 has integrated into its construction a 360' inlet connector which, as is nowadays well known, enables the vessel proper to be set down onto its base in any rotational orientation with respect to the base. A similar control is available from Strix Ltd. and is substantially as described in GB-A-2 339 496.

In use of our X4/Z5 controls combination and of the similar Strix control it is usual to provide a steam tube to duct steam from inside the vessel proper down to the steam control in the compartment beneath the heating element, the steam tube being formed in the body of the vessel proper or alternatively being formed as a separate tube passing through the heating element. It is furthermore usual to vent the steam through the bottom of the 3 vessel proper after it has caused the steam control to operate. We have identified a problem with this constructional arrangement, particularly if the Strix control is used, in that, as the steam leaves the vessel bottom, it impinges upon the upper surface of the base part of the cordless appliance which is relatively cold so that the steam condenses and forms a puddle on the surface of the base. This puddle is clearly visible when the vessel is lifted from its base and may cause the user to think that the vessel is leaking.

Objects and Suminn of the Invention; It is the object of the present invention to overcome or at least substantially reduce the abovernentioned problem and thereby prevent a user from concluding that his appliante is leaking and retun-fing it to whence it was purchased.

According to the present invention the abovementioned object can be achieved by arranging for venting of exhausted steam laterally from the lower periphery of the body of the vessel proper, rather than downwardly, so that it does not impinge on the cold surface of the appliance base part and does not condense there.

The above and further features of the invention are set forth in the appended claims and will be well understood from consideration of the following description of an exemplary embodiment which is illustrated in the accompanying drawings.

4 Description of the Drawings

Figure 1 is a cross-sectional side-elevation view of a cordless hot water jug embodying the present invention; Figure 2 is a cross-sectional side-elevation view of the hot water jug of Figure 1 taken on an axis 90' rotated from that on which Figure 1 is taken; Figure 3 is a perspective view of a vessel body moulding comprising part of the hot water jug of Figures 1 and 2; Figure 4 is an enlarged cross-sectional view of a bottom part of the vessel body moulding shown in Figure 3; and Figures 5A to 5F show various views of a bottom moulding to be affixed to the bottom of the vessel body moulding shown in Figures 3 and 4, Figure 5A being a top plan view, Figures 5B and 5C being cross-sectional side-elevation views on the lines G...G and H... H of Figure 5A, Figure 5D being a perspective view of the bottom moulding from the side thereof which is outermost when the bottom moulding is assembled with the vessel body moulding, and Figures 5E and 5F being perspective views from different viewpoints of the other side of the bottom moulding.

Detailed Description of the Embodiment:

Referring first to Figures 1 and 2, the illustrated appliance is a cordless hot water jug comprising a vessel proper 1 and a base 2 upon which the vessel proper has to be seated in order that power can be supplied through the base to a planar heating element that is provided in the vessel proper. In the illustrated embodiment, the heating element is designated 3 and is of the aforementioned thick film type. Associated with the heating element 3 is an X4 element overtemperature protection control 4 and a Z5 steam sensor 5 as aforementioned. The X4 control incorporates a 3600 inlet connector which, when the vessel proper 1 is seated on its base 2, mates with a 360' outlet connector (our CS4 product, for example, which is substantially as described in GB-C-2 285 716) to enable power supplied to the base to be connected through to the vessel proper.

In operation of the appliance abovedescribed, when water is heated to boiling in the vessel proper, steam is generated and accesses the Z5 steam sensor by way of a duct 6 which is moulded into the plastics material body of the vessel proper 1. The steam impinges upon the bimetallic actuator of the Z5 steam sensor and causes the sensor to operate, thereby switching off the power supply to the vessel heating element 3. An on/off lever 7 is pivotally mounted in the vessel proper 1 and engages with the trip lever of the Z5 steam sensor to enable the steam sensor switch to be operated manually, especially for resetting the switch after it has operated.

Figure 3 shows a moulded plastics body part 8 of the vessel proper 1 in perspective view and from underneath. A seating 9 for the thick film heating element 3, which is not shown in Figure 3, is provided, together with 6 attachment points 10 enabling the heating element to be secured in place. The bottom end 11 of the steam duct 6 is shown and its inward face 12 is shaped to fit closely to the external profile of the respective part of the steam sensor 5, formations (not shown) being provided on the steam sensor for making substantially sealing engagement with the steam duct. As will be described hereinafter, the bottom moulding illustrated in Figures 5A to 5F engages substantially sealingly with the steam sensor in similar fashion so that the steam sensor is substantially sealingly enclosed in an enclosure defined at the bottom end of the steam duct. Vents 13 are provided in the bottom edge of the plastics body part 8 for enabling steam to exit laterally (with respect to the normal vertical orientation of the appliance) from this enclosure.

Figure 4 is an enlarged cross-sectional showing of a bottom part of the vessel body moulding 8. The thick film heating element 3 is shown seated in the seating 9 with a seal 14 around the element periphery and a clamping ring 15 holding the element in place. The steam duct 6 is shown terminating in its bottom wall 12 and one of the vents 13 is shown.

Figures 5A to 5F show a moulded plastics bottom closure 16 for the body moulding 8 of the vessel proper. As shown, the bottom closure 16 is concavely dished complementarily to the convex upper surface of the base part 2 of the appliance and has a central opening through which the outlet connector of the base part can access the inlet connector of the appliance proper. Of particular relevance to the present invention are the formations 7 generally referenced 17 which interface with the steam sensor 5 when the bottom closure 16 is affixed to the body moulding 8 to complete the assembly of the vessel proper 1. As mentioned hereinbefore, these formations 17 co-operate with the shaped bottom end of the steam duct 6 to enclose the steam sensor 5 substantially sealingly so that the only exit available for exhausted steam is provided by the vents 13 which direct the steam laterally outwards away from the X4 element protector control 4 and away from the underlying upper surface of the base part 2 of the appliance. The bottom closure 16 may be affixed by means of screw-threaded fastenings to the X4 control and/or may be arranged to snap fit into the bottom of the vessel body moulding 8.

It will be appreciated that the arrangement described avoids the problem of condensate forming on the surface of the base 2 of the appliance by directing exhaust steam outwards away from the base. The concave shape of the bottom closure 16 will also assist draining in the event that slight condensation might occur in the stem sensor enclosure, but this is not an essential feature of the invention.

Having thus described the invention by reference to a specific embodiment, it is to be well appreciated that the described embodiment is exemplary only and that modifications and variations thereto are possible without departure from the spirit and scope of the invention. For example, while the invention has been described in the foregoing by reference to C 8 cordless appliances, the teachings of the invention are nonetheless applicable to corded appliances.

9

Claims

Claims:

1. An electrically heated water boiling vessel having a steam sensor mounted in a bottom compartment of the vessel with a steam duct conveying steam generated in operation of the vessel to the steam sensor, and wherein means are provided for venting exhaust steam laterally outwardly of the vessel.

2. A vessel as claimed in claim 1 having a planar heating element and wherein said compartment is below the heating element.

3. A vessel as claimed in claim 1 or 2 wherein the steam duct terminates in an enclosure sealingly embracing part at least of said steam sensor, said enclosure having one or more apertures arranged to vent steam laterally.

4. A vessel as claimed in any of the preceding claims comprising a cordless vessel proper and a base, the arrangement being such that power can be conducted from the base to the vessel proper when the vessel proper is seated on the base.

5. A vessel as claimed in claim 4 wherein the vessel proper and the base are provided with respective parts of an electrical connector set which enables the vessel part to be operatively coupled to the base throughout 360' of relative rotational orientation.

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