AU2015224376A1 - Heating vessel with noise reduction - Google Patents
Heating vessel with noise reduction Download PDFInfo
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- AU2015224376A1 AU2015224376A1 AU2015224376A AU2015224376A AU2015224376A1 AU 2015224376 A1 AU2015224376 A1 AU 2015224376A1 AU 2015224376 A AU2015224376 A AU 2015224376A AU 2015224376 A AU2015224376 A AU 2015224376A AU 2015224376 A1 AU2015224376 A1 AU 2015224376A1
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- heating
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- perforated plate
- heating chamber
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Abstract
A heating vessel is described for heating liquid located in a heating chamber (12) of the heating vessel. The vessel comprises a contact plate (16) defining a base of the heating chamber and having a contact surface that, in use, is in contact with the water located in 5 the heating chamber; a heating element (20) located below the base of the heating chamber and in thermal communication with the contact plate; a perforated plate (19) located in the heating chamber above the contact surface, wherein the perforated plate comprises a substantially planar disc having a plurality of holes (34) enabling fluid flow between a first volume of the heating chamber between the contact surface and the 10 perforated plate and a second volume of the heating chamber above the perforated plate. CC, len p ~--------- 2 C))
Description
1001209815 2015224376 07 Sep 2015
Heating vessel with noise reduction
Field of the invention
The present invention relates to vessels for heating liquids, such as a kettle. In particular, the invention relates to heating vessels that reduce the noise emitted during 5 heating of the liquid in the vessel.
Background of the invention
It is desirable to reduce the noise that arises during heating of liquids in heating vessels such as kettles, urns and steamers. Some previously described systems address the problem by proposing a noise-reduction coating on the water-facing side of 10 the heater plate of an under-floor heater system. The coating is thought to work by controlling the growth of bubbles at nucleation sites on the heater plate through the provision of adjacent regions with different surface tensions. An example of a system with a noise-reduction coating and a disruptor member positioned above the heating element is described in EP 1 859 711 B1. 15 Reference to any prior art in the specification is not an acknowledgment or suggestion that this prior art forms part of the common general knowledge in any jurisdiction or that this prior art could reasonably be expected to be understood, regarded as relevant, and/or combined with other pieces of prior art by a skilled person in the art. 20 Summary of the invention
According to a first aspect of the invention there is provided a heating vessel for heating liquid located in a heating chamber of the heating vessel, comprising: a) a contact plate defining a base of the heating chamber and having a contact surface that, in use, is in contact with the water located in the heating chamber; 25 b) a heating element located below the base of the heating chamber and in thermal communication with the contact plate; c) a perforated plate located in the heating chamber above the contact surface, wherein the perforated plate comprises a substantially planar disc having a plurality of 1 1001209815 2015224376 07 Sep 2015 holes enabling fluid flow between a first volume of the heating chamber between the contact surface and the perforated plate and a second volume of the heating chamber above the perforated plate.
The heating element may be an arcuate sheathed resistive heating element and 5 wherein the perforated plate comprises a non-perforated annular region matching a size and configuration of the heating element, the non-perforated annular region configured to lie above the heating element.
The perforated plate may comprise at least one shallow circular trench to enhance a rigidity of the perforated plate. The depth of the trench may be approximately 10 the same as the thickness of the plate.
The perforated plate may comprise a plurality of concentric rings of holes perforating the perforated plate.
The perforated plate may be made of stainless steel. The perforated plate and the contact surface may be free of noise-reducing coatings. 15 According to a further aspect of the invention there is provided a heating vessel for heating liquid located in a heating chamber of the heating vessel, comprising: a) a contact plate defining a base of the heating chamber and having a contact surface that, in use, is in contact with the water located in the heating chamber; b) a heating element located below the base of the heating chamber and in 20 thermal communication with the contact plate; c) a perforated plate located in the heating chamber above the contact surface, wherein the perforated plate comprises a substantially planar stainless steel disc comprising: • a central circular region comprising a plurality of holes configured in 25 concentric circles, the holes enabling fluid flow between a first volume of the heating chamber between the contact surface and the perforated plate and a second volume of the heating chamber above the perforated plate; 2 1001209815 2015224376 07 Sep 2015 • two shallow circular trenches concentric with the central circular region; • an annular non-perforated region that matches a shape and configuration of the heating element and is positioned above the heating element; 5 • a peripheral lip elevated above a principal plane of the perforated plate; and • a plurality of tabs extending from the peripheral lip and bonded to the contact plate.
As used herein, except where the context requires otherwise, the term "comprise" and variations of the term, such as "comprising", "comprises" and 10 "comprised", are not intended to exclude further additives, components, integers or steps.
Further aspects of the present invention and further embodiments of the aspects described in the preceding paragraphs will become apparent from the following description, given by way of example and with reference to the accompanying drawings. 15 Brief description of the drawings
Figure 1A is a cut-away view of kettle with a noise-reduction arrangement.
Figure 1B is a front view of the kettle of Figure 1 A.
Figure 1C is a perspective view of a perforated plate that is positioned in the heating chamber of the kettle of Figure 1 to provide noise reduction. 20 Figures 2A, 2B and 2C are respectively a cut-away view, a top view and a side view of the perforated disc of Figure 1C in relation to base of the heating chamber of the kettle and the kettle heating element.
Figures 3A, 3B and 3C are, respectively, a cut-away view, a top view and a side view of the perforated plate of Figure 1C. 25 Figures 4A, 4B and 4C are, respectively, a cut-away view, a top view and a side view of the perforated plate and the heating element of the kettle.
Figure 5A is a perspective view of a kettle, and Figure 5B is a cut-away view of the kettle illustrating the location of the perforated plate. 3 1001209815 2015224376 07 Sep 2015
Figures 6A, 6B, 6C and 6D are further views of the perforated plate in relation to the other components of the kettle, including the contact plate and heating element.
Detailed description of the embodiments
Figure 1A shows a cross-sectional view of an electric kettle 10, sectioned along 5 line AA seen in the front view of the kettle 10 in Figure 1B. The electric kettle has a heating chamber 12, which holds the water to be boiled. The water may be poured into the heating chamber 12 of the kettle through the pouring spout 14 or through the lid of the kettle 10. A handle is provided for a user to lift the kettle 10 and pour water out of the pouring spout 14. Kettle 10 is a cordless kettle that in use is placed on a separate 10 base to receive power. The base is not illustrated in the drawings. The noise-reduction features described herein may also be used in kettles that have a power cord plugging directly into the heating vessel.
The base wall of the heating chamber 12 is defined by a contact plate 16. Water stored in the heating chamber 12 is in direct contact with a contact surface of the 15 contact plate 16. The contact plate 16 may be formed from stainless steel. Other materials which are suitable for water contact and are resistant to high temperatures and oxidation may be used.
The kettle has a perforated plate 19 located in the heating chamber 12 above the contact plate 16. The perforated plate 19 acts to reduce noise when water is heated in 20 the chamber 12.
The contact plate 16 forms part of a heater assembly 18. The heater assembly is located underneath the heating chamber 12 on the opposite side of the contact plate to the heating chamber 12. The heater assembly 18 is powered by a power source (not shown) which is external to the kettle 10. 25 The heat used to boil the water is generated by a heating element 20, which is curved and terminates in cold tails 22. Preferably the heating element 20 is powered by electricity. The heating element 20 shown is a resistance element. Other types of heating elements may be used. For a kettle a 2400W sheathed arcuate heating element is often used. 4 1001209815 2015224376 07 Sep 2015
The arcuate heating element 20 is bonded to a peripheral region at or near an outer edge of a heat distribution plate or billet 24, seen for example in Figure 2A. The bonding achieves a good thermal coupling between the heating element 20 and the heat distribution plate 24 so that heat generated by the heating element 20 is rapidly 5 and efficiently transferred to the heat distribution plate 24. Many known bonding techniques are suitable, including induction welding, flame or oven welding and impact welding.
The heat distribution plate 24 is induction brazed to the contact plate 16 so there is a good thermal coupling between the heat distribution plate 24 and the contact plate I0 16. Many other known bonding techniques are suitable, including the bonding techniques mentioned above.
The heat distribution plate or billet 24 may be formed from aluminium, which is a good thermal conductor, and is of sufficient thickness to evenly distribute heat from the heating element 20 across the extent of the heat distribution plate 24. Alternative 15 materials for the heat distribution plate 24 include other metals and metal alloys. The heat distribution plate 24 is generally thicker than the contact plate and formed from a material which is a better thermal conductor than the contact plate.
The heat distribution plate 24 defines a void 26. In the arrangement of Figure 2A the void is cylindrical with an outer diameter surrounded by the heat distribution plate 20 24. The void in this arrangement provides access to the contact plate 16 through the heat distribution plate 24. The void 26 forms a thermally insulating zone. This is because heat which is transmitted from the heating element 20 to the heat distribution plate 24 is not as readily transmitted across the void 26. The region of the contact plate 16 located adjacent the void 26 does not conduct significant amounts of heat when 25 compared to the aluminium heat distribution plate 24 because the contact plate 16 is thin and formed from stainless steel, which has a lower thermal conductivity.
An electronic temperature sensor is positioned in the void 26. The void 26 provides a thermally insulating zone around the electronic temperature sensor 28. Fleat from the heat distribution plate 24 is not readily transmitted to the electronic temperature 30 sensor 28. As a result, the electronic temperature sensor 28 is thermally insulated and 5 1001209815 2015224376 07 Sep 2015 is not undesirably influenced by the temperature of the heating element 20 and heat distribution plate 24.
The thermally insulating zone and the temperature sensor may be located between the cold tails 22 of the heating element 20. The cold tails do not generate 5 significant amounts of heat, so the electronic temperature sensor is further insulated from the heat generated by the heating element 20. Instead of being empty, the void 26 may be filled, either partially or wholly, with a thermally insulating material, such as silicone or rubber.
The temperature sensor is positioned in close proximity to the contact plate 16. I0 Optionally, the temperature sensor may touch the contact plate 16. This improves the thermal coupling between the electronic temperature sensor and the contact plate 16. The thermal coupling may be further improved using known techniques, such as applying a heat transfer paste.
It is an advantage that the temperature sensor is in thermal contact with the 15 contact plate 16. When water contained in the heating chamber 12 of the kettle 10 heats up, the contact plate 16 will heat to a similar temperature. Due to the void 26, the region of the contact plate 16 located within the void is insulated from the heat distribution plate 24 and will more accurately reflect the temperature of the water. Since the temperature sensor is in thermal communication with the contact plate 16, it senses the water >0 temperature with greater accuracy and responsiveness. The temperature sensing arrangement is described in earlier patent applications by the present applicant including AU 2009101273, the contents of which are incorporated herein by reference.
The temperature sensor is typically a thermistor. NTC thermistors formed from metal oxides are suitable. A thermistor has a number of advantages over other types of 25 temperature sensors. A thermistor senses the temperature of water in the kettle within a continuous range. This provides significantly more information on the temperature of the water than, for example, a bimetallic actuator. A bimetallic actuator is typically activated only when the water reaches a threshold temperature value and is deactivated when the water falls below a threshold temperature value. As a result, a bimetallic actuator only 30 senses whether the water temperature is above or below a threshold value. The 6 1001209815 2015224376 07 Sep 2015 thermistor provides responsive and accurate readings because it is positioned in a thermally insulating zone in thermal communication with the contact plate 16.
Figure 1C is a perspective view of the perforated plate 19 that forms part of the noise reduction arrangement. At the centre of the plate 19 there is a hole that, in use, 5 provides passage for liquids and gases between the regions above and below the perforated plate. Around the central hole there are six concentric rings of holes 34 perforating the disc 19. A first shallow trench 36b surrounds the central portion of the disc 19. Outside the trench 36b there is a further concentric ring of holes perforating the disc 19. Then there is a second shallow circular trench 36a, concentrically disposed with I0 respect to the rings of holes. Radially outward of the second trench 36a there is a further ring of holes perforating the disc. Beyond this rim there is an annular region 38 which is not perforated. Continuing outward from the annular unperforated region there is a further concentric ring of holes 34 perforating the disc. The outer periphery of the disc 19 is formed into a raised lip 42. Three tabs or feet 32 extend radially outward from 15 the peripheral lip 42 and extend downward below the principal plane of the perforated disc 19.
There is a cut-out region 40 formed in the peripheral lip 42. When the kettle 10 is assembled, the cut-out region 40 accommodates a steam tube that allows the passage of steam from the heating chamber 12 of the kettle down into the heater assembly 18. >0 Figure 2 illustrates how the perforated plate 19 is positioned on the contact plate of the kettle 10. As best seen in the cut-away view of Figure 2A, the contact plate 16 has a central planar portion 16b that covers most of the radial extent of the contact plate 16. The portion 16b is induction braised to the heat distribution plate 24. Radially outward of the planar portion 16b, the contact plate is formed into a raised peripheral lip 25 16a. When the perforated plate 19 is positioned on top of the contact plate 16, the tabs or feet 32 of the perforated plate 19 rest on the peripheral lip 16a of the contact plate 16. The perforated disc 19 is bonded to the contact plate 16, including the bonding techniques mentioned above.
As seen in the top view of Figure 2B, the diameter of the contact plate 16 is 30 greater than the diameter of the perforated disc 19. The diameter of the perforated plate 19 is approximately equal to the diameter of the central planar part 16b of the contact 7 1001209815 2015224376 07 Sep 2015 plate. When the disc 19 and the contact plate 16 are arranged concentrically, the peripheral lip 16a extends beyond the perforated disc 19, allowing the feet or tabs 32 to rest on the peripheral lip 16a.
The perforated disc 19 may be formed of stainless steel. The holes 34 may be 5 formed by any suitable technique, for example drilling or punching. In one arrangement the holes have a diameter of 2.5mm and are punched in the perforated disc 19, which is press formed. In another arrangement, the holes 34 have a diameter of 1.5mm and are drilled in the perforated plate 19.
As seen in Figure 2A, a contained region 30 is formed between the contact plate I0 16 and the perforated disc 19. In one arrangement the distance between the principal plane of the perforated disc 19 and the plane of the contact plate 16b is around 13mm. In use, there is fluid flow between the contained region 30 and the general volume of the heating chamber 12, both through the holes 34 and around the periphery of the perforated disc 19. 15 Figures 3A, 3B and 3C further provide a top view, side view and cut-away view of the perforated disc 19. The cut-away view of Figure 3A illustrates the depth of the shallow trenches 36a and 36b relative to the main plane of the perforated disc 19. In one arrangement, the thickness of the plate 19 is 0.7mm.
The shallow trenches 36a, 36b provide greater rigidity to the perforated disc 19. It >0 is considered that the rigidity of the disc contributes to the noise-reducing effect of the perforated disc during heating of the contents of the heating chamber 12.
Figures 4A, 4B and 4C illustrate the relative location of the perforated disc 19 and the heating element 20 when the kettle 10 is assembled. The heating element 20 and the plate 19 are arranged concentrically. The heating element 20 lies below the 25 annular unperforated region 38. Thus, there are no holes in the perforated disc 19 that are positioned immediate above the region of the heating element 20.
Figure 5A is a perspective view of the kettle 10, and Figure 5B is a cut-away view that provides a view of the noise-reduction assembly. The contained region 30 that lies between the perforated plate 19 and the contact plate 16 is a relatively small volume 30 compared with the overall volume of the heating chamber 12. The provision of the 8 1001209815 2015224376 07 Sep 2015 perforated plate 19 is thought to reduce the noise produced during heating of the liquids by acting as a baffle that reflects sound back towards the contact plate when noise is generate by bubble formation at the contact plate 16. The advantageous effect of the perforated disc 19 is considered to be enhanced by the rigidity provided by the use of 5 stainless steel and the provision of the shallow trenches 36a, 36b formed in the perforated disc 19.
Both the contact plate 16 and the perforated disc are formed of stainless steel, without any noise-reduction coating. Experience of systems with such coatings has indicated potential problems where the coating results in the water having a taste and I0 odour that are discernible to some users. It has also been noted that noise-reduction coatings may degrade over time. Consequently, the presently-described arrangements do not use noise-reduction coatings.
Figures 6A, 6B, 6C and 6D show further exploded and cut-away views of the components of the noise-reducing kettle 10. 15 The noise-reduction arrangement has been described with reference to a kettle.
Similar noise-reduction arrangements may be used in other vessels for heating liquids, such as urns or steamers.
Type of kettle Kettle type A Kettle type A with quiet boil Kettle type B Kettle type B with quiet boil Kettle type C Kettle type C with quiet boil Measured noise (dB(A)) 59 55.5 62.2 59.9 57.5 52
Table A - noise measurements on different ketl :les during heating
Experiments have been performed on three different types of kettles. In each 20 case modified versions of the kettles were assembled to include the perforated disc 19. Table A illustrates that for each of the three types of kettle, the inclusion of the perforated disc 19 leads to a reduction in measured noise when liquids are heated in the respective kettles. 9 1001209815 2015224376 07 Sep 2015 5
It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention. 10
Claims (9)
1. A heating vessel for heating liquid located in a heating chamber of the heating vessel, comprising: a) a contact plate defining a base of the heating chamber and having a contact surface that, in use, is in contact with the water located in the heating chamber; b) a heating element located below the base of the heating chamber and in thermal communication with the contact plate; c) a perforated plate located in the heating chamber above the contact surface, wherein the perforated plate comprises a substantially planar disc having a plurality of holes enabling fluid flow between a first volume of the heating chamber between the contact surface and the perforated plate and a second volume of the heating chamber above the perforated plate.
2. A heating vessel according to claim 1 wherein the heating element is an arcuate sheathed resistive heating element and wherein the perforated plate comprises a nonperforated annular region matching a size and configuration of the heating element, the non-perforated annular region configured to lie above the heating element.
3. A heating vessel according to claim 1 or 2 wherein the perforated plate comprises at least one shallow circular trench to enhance a rigidity of the perforated plate.
4. A heating vessel according to claim 3 wherein the shallow circular trench is press-formed in the perforated plate.
5. A heating vessel according to any one of the preceding claims wherein the perforated plate comprises a plurality of concentric rings, each ring comprising a series of holes perforating the perforated plate.
6. A heating vessel according to any one of the preceding claims wherein the perforated plate is made of stainless steel.
7. A heating vessel according to any one of the preceding claims wherein the perforated plate and the contact surface are free of noise-reducing coatings.
8. A heating vessel according to any one of the preceding claims further comprising a heat distribution plate bonded to an underside of the contact plate, the heat distribution plate being thicker than the contact plate and having a thermal conductivity that is greater than a thermal conductivity of the contact plate, and wherein the heating element is bonded to a lower surface of the heat distribution plate.
9. A heating vessel for heating liquid located in a heating chamber of the heating vessel, comprising: a) a contact plate defining a base of the heating chamber and having a contact surface that, in use, is in contact with the water located in the heating chamber; b) a heating element located below the base of the heating chamber and in thermal communication with the contact plate; c) a perforated plate located in the heating chamber above the contact surface, wherein the perforated plate comprises a substantially planar stainless steel disc comprising: • a central circular region comprising a plurality of holes configured in concentric circles, the holes enabling fluid flow between a first volume of the heating chamber between the contact surface and the perforated plate and a second volume of the heating chamber above the perforated plate; • two shallow circular trenches concentric with the central circular region; • an annular non-perforated region that matches a shape and configuration of the heating element and is positioned above the heating element; • a peripheral lip elevated above a principal plane of the perforated plate; and • a plurality of tabs extending from the peripheral lip and bonded to the contact plate to support the perforated plate above the contact surface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AU2015224376A AU2015224376B2 (en) | 2015-09-07 | 2015-09-07 | Heating vessel with noise reduction |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AU2015224376A AU2015224376B2 (en) | 2015-09-07 | 2015-09-07 | Heating vessel with noise reduction |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| AU2015224376A1 true AU2015224376A1 (en) | 2017-03-23 |
| AU2015224376B2 AU2015224376B2 (en) | 2021-08-05 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| AU2015224376A Active AU2015224376B2 (en) | 2015-09-07 | 2015-09-07 | Heating vessel with noise reduction |
Country Status (1)
| Country | Link |
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| AU (1) | AU2015224376B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113163969A (en) * | 2018-10-23 | 2021-07-23 | 布瑞威利私人有限公司 | Water jug |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3136954B2 (en) * | 1995-07-11 | 2001-02-19 | 松下電器産業株式会社 | Electric water heater |
| GB0303840D0 (en) * | 2003-02-20 | 2003-03-26 | Renton Garry | Safety kettle |
| GB0610427D0 (en) * | 2006-05-25 | 2006-07-05 | Strix Ltd | Improvements in liquid heating vessels |
| WO2008071983A2 (en) * | 2006-12-14 | 2008-06-19 | Otter Controls Ltd | Electric water heater |
| AU2009101273B4 (en) * | 2009-09-17 | 2010-10-28 | Sunbeam Corporation Pty Ltd | Improved temperature sensor for an electric kettle |
| JP2015089476A (en) * | 2013-11-07 | 2015-05-11 | ユーテック株式会社 | Liquid heater and liquid extraction device |
-
2015
- 2015-09-07 AU AU2015224376A patent/AU2015224376B2/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113163969A (en) * | 2018-10-23 | 2021-07-23 | 布瑞威利私人有限公司 | Water jug |
Also Published As
| Publication number | Publication date |
|---|---|
| AU2015224376B2 (en) | 2021-08-05 |
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Legal Events
| Date | Code | Title | Description |
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| HB | Alteration of name in register |
Owner name: SUNBEAM CORPORATION PTY LTD Free format text: FORMER NAME(S): SUNBEAM CORPORATION LIMITED |
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| PC1 | Assignment before grant (sect. 113) |
Owner name: NEWELL AUSTRALIA PTY LTD Free format text: FORMER APPLICANT(S): SUNBEAM CORPORATION PTY LTD |
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| FGA | Letters patent sealed or granted (standard patent) |