GB2323021A - Water kettle with steam channel - Google Patents

Abstract

A water kettle 1 with an automatic shut-off facility responsive to steam generation comprises a heatable vessel 3 heated by an element 5, a steam responsive bi-metallic sensor 19, a steam shaft 17 and a closable lid 13 hinged at pin 43 to handle 9. Steam, generated by heating water, enters inlet opening 75 and travels horizontally via channel portions 67 and 55. Upon boiling, with the commensurate increase in steam pressure, steam is forced through opening 15 and into shaft 17 to the sensor 19. The regulating unit 21 switches off the power to the element 5 about five seconds after boiling has commenced. The channel 55, 67 is further provided with openings 77, 79 to allow condensed water to drip back into the vessel 3. The lid 13 may be locked in use by utilising lock handle 59 in concert with lock opening 57.

Description

1 WATER KETTLE WITH STEAM CHANNEL The present invention relates to a water

kettle.

2323021 A water kettle is described in German Utility Model G 91 06 751.0, in which an electrical switch for switching-on and switching-off the kettle is accommodated in the kettle handle and is actuable at least by means of a bimetallic element contacted by steam. In that case, the handle interior is connected with the vessel interior by way of a steam outlet opening, which is arranged at the edge of the vessel, of the handle. For safety reasons, water kettles of that kind have a stop switch, which switches off the electric heating as soon as the liquid or water in the vessel begins to boil. The switch is actuated by the bimetallic element, past which the arising hot air and ultimately the steam flow. For this reason a flow connection must be present between the vessel interior and the thermal operating element. When bubbling of the water occurs, thus the boiling point is reached, a considerable amount of steam arises relatively suddenly. This acts in the manner of a steam jet with high heat content. The latter presupposes a slight overpressure in the vessel interior, for which reason such kettles are provided with a lid.

There remains a need to improve the switch-off behaviour of a water kettle, especially a kettle with a sensor in the base region of the vessel.

i According to the present invention there is provided a water kettle comprising a heatable vessel, which is closable by means of a lid, with a pouring opening and a handle as well as with a temperature or steam sensor, which is arranged in the base region or handle region of the vessel, for the switching-off of the water kettle, and with a steam outlet opening at the rim of the vessel, through which the steam arising during boiling of the water gets to the sensor. characterised in that a steam channel is provided, which has a steam inlet spaced inwardly from the periphery of the vessel rim and connects this inlet with the steam outlet.

The steam inlet displaced in the direction of the vessel centre significantly reduces the switching-off time of the kettle. By switchingoff time is meant the time which passes after attainment of the boiling point up to the switching off, triggered by the sensor, of the kettle heating. Thus, particularly in the case of a sensor arranged in the base region of the vessel, a reduction in the switching-off time from about 20 to 30 seconds to about 5 2 seconds may be achievable. The cause for this may be that in the region of the vessel centre a higher steam pressure prevails than in the edge region thereof, and in some cases that an overpressure can build up in the preheated steam channel, which on attainment of the boiling point then forces, in a short time, the air volume in the steam channel downwardly to the sensor in the base region of the kettle.

Advantageously, the steam channel is substantially tubular. Particularly short switch-off times can be realised by this substantially closed construction of the channel.

In a preferred embodiment the steam channel is formed substantially at the lid. Thus, on opening of the lid the steam channel, which otherwise protrudes interferingly into the vessel, can pivot away from the vessel.

In order to ensure that water condensing in the channel does not flow to the sensor, at least one additional opening serving as an outflow for condensate water is preferably provided in the base of the steam channel.

A notable shortening of the switching-off time may be able to be achieved if the steam inlet is arranged approximately in the centre of the vessel, especially directly below the lid. There, the steam pressure arising during boiling is higher than in the edge regions of the vessel. The channel length is preferably between about one third and two-thirds of the vessel diameter.

Advantageously, the steam channel extends substantially horizontally. This on the one hand prevents water, which condenses in the channel, from running to the sensor and on the other hand promotes build-up of an overpressure in the channel.

Preferably, the cross-section of the steam inlet is about 2 to 7, for preference about 4, square centimetres. This favours quick switching-off of the kettle.

The switching-off time can be further reduced if the cross-section of the steam inlet opening is larger, preferably at least twice as large, than the cross-section of the steam outlet.

3 Expediently, the pouring opening of the water is substantially closable by the lid. The build-up of an appropriate overpressure in the kettle when the lid is closed can thereby be reliably guaranteed.

An embodiment of the present invention will now be more particularly described by way of example with reference to the following drawings, in which:

Fig. 1 is a schematic side view of a water kettle embodying the invention, with closed lid; and Fig. 2 is a sectional view, substantially along the line 11-11 in Fig. 1 and to enlarged scale, of the upper end part of the kettle.

Referring now to the drawings, there is shown a water kettle 1 comprising a high-quality or stainless steel vessel or pot 3 at the base underside of which is fastened a known form of heating element 5. Moreover, attached to the base region of the vessel 3 is a base housing 7 of temperature-resistant synthetic or plastics material and a handle part 9, which extends above the height of the wall of the vessel 3 and is of synthetic or plastics material, with an insert 10. The vessel 3 has a spout 11 opposite the handle part 9 and is closable at its upper edge portion by a lid 13 hinged at the handle region. The vessel 3 or handle part 9 has a steam outlet opening 15 at the upper end portion of the vessel. A steam shaft 17, which extends vertically along the wall of the vessel 3, of the handle part 9 adjoins this. The steam shaft 17 communicates with an opening of the base housing 7. Arranged in this region in the housing 7 in known manner is a bimetallic sensor element 19 coupled to a regulating unit 21, which is similarly arranged in the housing 7, for controlling the kettle 1, in particular the heating element 5. Moreover, the housing 7 has steam openings 22 in the region below the sensor element 19. From these, the steam, which is conducted downwardly during boiling of the water, issues from the handle part 9 after flowing against the sensor element 19. In addition, a coupling unit 23, which is accessible through a circular opening in a base plate 25 of the kettle 1, is connected with the regulating unit 21. The water kettle 1 can be set down on a base 27, which has a plug unit corresponding to the coupling unit 23. In that case, the regulating unit 21 and the heating element 5 of the water kettle 1 are connected with a mains voltage supply provided in the base 27.

The lid 13 has a lid body 35 with a circular plate 37. The lid 13 lies, by its circumferential edge 38 against the circumferential upper end portion of the vessel 3. An apron 39 4 extends, spaced inwardly from the edge 38, vertically from the plate 37 down into the interior of the vessel 3. In the region of the spout 11, a cover plate 40 extends at an angle outwardly and downwardly from the apron 39. Two steam openings 41 are also provided in this region of the apron. A horizontal bearing pin 43 is formed, at a double-armed projection of the plate 37, at the end portion of the plate 37 opposite the cover plate 40. The plate 37 moreover has in its central region two parallelly extending troughlike grip recesses 45, which are separated from one another by a separating elevation 47 along a straight line formed through the cover plate 40 and the bearing pin 43.

The lid 13 is pivotably mounted on the handle part 9 via an additional bearing part 51. For that purpose the part 51 is screw-connected with the handle part 9, and the pin 43 of the lid 13 is mounted between the underside of a plate-shaped bearing arm 53 of the part 51 and a correspondingly formed bearing surface of the handle part 9. A channel portion 55 of rectangular cross-section adjoins the ann 53 and extends in the direction of the vessel centre. In the region of the vessel wall the bearing part 51 bears by the base of the channel portion 55 directly against a hook portion 56 of the handle part, which hook portion engages over the wall of the vessel 3 and hooks the handle part 9 to the upper edge of the vessel 3. In the lower region of the hook portion 56, the handle part 9 is screw-connected to the vessel 3 by means of a screw 99 (Fig. 2). The steam outlet opening 15, to which the steam shaft 17 is connected, is provided above the hook portion 56 and is formed in the handle part 9. A lock opening 57 is formed in the top wall of the channel portion 55. An elongate lock handle 59 of U-shaped cross-section (omitted in Fig. 2 for reasons of simplicity) is provided at the vessel 3 for locking and unlocking the lid 13. The lock handle 59 sits on the elevation 47, wherein the two side limbs of the handle 59 bear against the side walls of the elevation 47 and are retained by detent means (not shown), which are formed in the limbs, at the lid 13. The lock handle 59 thus engages around the elevation 47. An entraining arm 61 is formed at the underside of the elongate main plate of the lock handle 59 to project vertically downwardly therefrom. The entraining arm 61 moves, on displacement of the lock handle 59, into a spring chamber 63, which is formed in the elevation 47, against the resistance of a compression spring (not shown) arranged therein. Through displacement of the lock handle 59 in the direction of the handle part 9, a lock 65, which is arranged in the end portion thereof and which projects vertically downwardly through a lid opening 64, is slidable out of the region of the lock opening 57 of the bearing part 51, whereby the hinged lid 13 can be pivoted upwardly.

A tubular steam channel portion 67 is formed at the underside of the lid 13. The channel portion 67 is bounded downwardly by a base plate 69, upwardly by a lower side 71 of the elevation 47 and laterally by two inner sides 73 of the elevation 47. The channel portion 67 has a steam inlet opening 75 approximately in the middle of the vessel 3. The channel portion 67 extends up to the channel portion 55 and is continued by this to the steam outlet opening 15. First outflow openings 77 are arranged in the base plate 69 of the channel portion 67, and second outflow openings 79 in the base of the adjoining channel portion 55 of the bearing part 51, for water condensing in the channel portions.

Steam arising during boiling of the water rises upwardly. It enters the steam inlet opening 75 of the steam channel formed by the channel portions 55 and 67 and spreads out in horizontal direction along the channel portion 67 and the channel portion 55. The steam partly condenses along the channel 55, 67. With increasing boiling time the steam pressure rises in the substantially closed vessel 3 of the kettle 1. On attainment of the boiling point, a large amount of steam arises in a relatively short time. In that case the steam is quickly forced, via the steam channel, through the steam outlet opening 15, which has a smaller opening cross-section by comparison therewith, into the steam shaft 17 and downwardly to the sensor element 19. The regulating unit 21 thereby switches off the heating element 5 about five seconds after reaching the boiling point.

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Claims (13)

1. A water kettle comprising a water vessel provided with a pouring opening, a handle and a lid, switchable heating means for heating water in the vessel and a temperature or steam sensor for switching off the heating means, the kettle being provided with a steam outlet at the rim of the vessel for the passage of steam to the sensor and with a steam channel connected to the steam outlet and having a steam inlet spaced inwardly from the periphery of the vessel.

2. A kettle as claimed in claim 1, wherein the sensor is provided in the region of the base of the vessel or the handle.

3. A kettle as claimed in claim 1 or claim 2, wherein the channel is substantially tubular.

4. A kettle as claimed in any one of the preceding claims, wherein the channel is formed at least partly in the lid.

5. A kettle as claimed in any one of the preceding claims, wherein the channel is provided in the base thereof with water outlet means.

6. A kettle as claimed in any one of the preceding claims, wherein the steam inlet is arranged substantially at the centre of the vessel and in the region of the lid.

7. A kettle as claimed in any one of the preceding claims, wherein the channel extends substantially horizontally in the intended position of use of the kettle.

8. A kettle as claimed in any one of the preceding claims, wherein the cross-section of the steam inlet is substantially two to seven square centimetres.

9. A kettle as claimed in claim 8, wherein the cross-section is substantially four square centimetres.

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10. A kettle as claimed in any one of the preceding claims, wherein the cross-section of the steam inlet is larger than that of the steam outlet.

11. A kettle as claimed in claim 10, wherein the cross-section of the steam inlet is at least twice that of the steam outlet.

12. A kettle as claimed in any one of the preceding claims, wherein the pouring opening is substantially closable by the lid.

13. A water kettle substantially as hereinbefore described with reference to the accompanying drawings.