IMPROVEMENTS RELATING TO ELECTRICALLY POWERED LIQUID HEATING APPLIANCES AND CONTROLS THEREFOR

Abstract: A cordless electrical appliance (10) such as an electrical kettle has an element protection control (1) and an appliance power connector (4), the element protection control (1) and the appliance connector (4) being separate items which are coupled to respective ends of an elongate mounting bracket (18). The mounting bracket is affixed to the underside (16) of a planar heating element (12) by stud formations (17). By virtue of this arrangement the number of formations (17) provided on the planar heating element (12) can be minimized.

Description: IMPROVEMENTS RELATING TO ELECTRICALLY POWERED LIQUID HEATING APPLIANCES AND CONTROLS THEREFOR Field of the Invention: This invention concerns improvements relating to electrically powered liquid heating appliances and controls therefor. The present invention may be applied to liquid heating appliances such as electric kettles, hot water jugs, urns, pans, laboratory equipment etc., and in the following the invention will be described with reference to electric kettles and hot water jugs though it is to be understood that the invention is not limited to such appliances. Background of the Invention: In the field of electric kettle design, there has been a recent move away from the use of conventional metal sheathed heating elements to using planar heating elements. Planar heating elements have previously been incorporated into metal bodied appliances without undue difficulty, for example by forming the element as a bottom wall of the metal liquid heating vessel. With the widespread availability of lighter and cheaper plastics materials, plastics moulded liquid heating appliances have become popular. However, the incorporation of a planar heating element in such appliances has been more complicated. In European Patent EP 0 285 339 there is described a kettle having a moulded plastics body and incorporating a planar heating element as a bottom wall of the liquid heating vessel. The planar heating element is supported on a projecting ledge of the plastics body and has a large downwardly projecting pillar at the centre of its lower face. The element is clamped against a seal by securing a moulded bottom cover, which has a clamping flange around its periphery for engaging the projecting ledge, to the downwardly projecting pillar with a nut. An element protection control, for switching off the appliance in the event of an overtemperature condition arising at the heating element, is provided on the underside of the planar heating element and is wired to a power connector at the side of the appliance. This design is not suitable for cordless appliances and the central pillar prevents the desirable positioning of the power connector at the centre of the kettle base. It is also known from International Patent Application W094/18807, to provide a planar heating element mounted on an integral element protection control and power connector provided in an opening of a base wall of an appliance. The element is held in place by fasteners which pass through holes in the integral protection control and power connector and which are secured in the heating element. A sealing ring is provided between the raised planar element and the base wall to provide a watertight seal. A problem with such an arrangement is that it has among other things an overhanging element which is difficult to clean and an increased minimum water volume to be heated. In addition, such an arrangement lacks flexibility, the integration of the element protection control with the power connector limiting the ability of the appliance designer to design appliances with freedom and furthermore, imposing severe tolerance constraints upon the manufacturers of such appliances. Recently, there has been produced a cordless electric kettle incorporating a flat heating element. Cordless appliances have power supplied to the appliance proper via a base unit, the appliance proper and the base unit having complementary electrical connector parts adapted to come together to provide appropriate electrical connections through the base unit to the heating element in the appliance proper when the latter is seated on the base. An element protection control is mounted directly onto the underside of the element by fixing formations on the element. In addition, an appliance power connector is indirectly mounted onto the element via a metal mounting bracket. A moulded plastics bottom cover of the kettle is held in place by screws which pass through mounting holes of the connector, through holes in the bracket and which are screwed into a specially formed plastics moulding that is provided between the connector and the element. The construction of this kettle requires two separate mounting operations to secure the control and connector to the heating element. In addition, two additional flexible cables are required to make the electrical connections. These cables are quite expensive, being insulated with high temperature resistant insulation. Objects and Summary of the Invention: An object of the present invention is to overcome or substantially reduce at least some of the aforementioned problems. According to the present invention, in one of its aspects, there is provided a combination of an element protection control and an appliance power connector which are each coupled to a mounting bracket for mounting to a heating element of the appliance. The provision of a mounting bracket is advantageous over the known arrangements because it enables both the element protection control and the appliance power connector to be affixed to the heating element at a single location. Accordingly, separate mounting studs or the like need not be provided on the heating element for each of the control and the connector as in the conventional arrangements. Furthermore, the provision of the mounting bracket enables the assembly of the kettle to be simplified with the mounting of the control and connector being carried out in a single operation. The mounting bracket preferably includes means for accommodating small differences in the mounting position of the appliance power connector relative to the heating element. More specifically, the accommodating means may for example comprise an elongate through-hole in the mounting bracket for co¬ operating with a threaded fastener over a range of different positions. This feature provides for greater positional tolerance between mounting formations on the heating element to which the mounting bracket is fixed and mounting formations on a bottom cover of the appliance which may be affixed to the connector. The present invention also extends to an electrically powered heating appliance comprising a liquid heating vessel and a bottom cover and including an element protection control, an appliance power connector and a mounting bracket according to the teachings hereof. The invention is particularly, though not exclusively, applicable to liquid heating appliances wherein the electrical heating element of the appliance is of the planar type, for example as is described in British Patent Application GB-A-2 283 155. The above and further features of the present invention are set forth with particularity in the appended claims and together with the advantages thereof will become clear from consideration of the following detailed description of an exemplary embodiment of the invention which is illustrated in the accompanying drawings. Description of the Drawings: Figure 1 is a perspective view of an element protection control generally in accordance with the teachings of GB-A-2 194 099 and GB-A-2 248 724, specifically in accordance with the teachings of British Patent Application GB 9522594.2 a copy whereof is appended as an integral part hereof and as used in the hereinafter described exemplary embodiment of the present invention; Figure 2 is a perspective view of an appliance power connector in accordance with the teachings of WO94/06185, specifically in accordance with the teachings of the abovementioned and appended British Patent Application No. 9522594.2 and as used in the hereinafter described exemplary embodiment of the present invention; and Figure 3 is a part sectional, part cut-away side elevation view showing the element protection control of Figure 1 and the appliance power connector of Figure 2 connected together and to a mounting bracket serving additionally for mounting a heating element in a liquid heating appliance. Detailed Description of the Embodiment: Referring first to Figure 1 of the accompanying drawings, there is illustrated therein an element protection control 1 which is a modified form of the control that is described in GB-A-2 194 099 with reference to Figures 3A, 3B and 3C thereof, or a modified form of the control that is described in GB- A-2 248 724, or a modified form of the controls that are described in GB-A-2 283 155 and GB-A-2 283 156. More specifically, the element protection control 1 is as described in the appended copy of British Patent Application No. 9522594.2 which forms an integral part hereof. Reference should be had to the aforementioned 3 specifications and to the appended copy of British Patent Application No. 9522594.2 for a full understanding of all aspects and advantages of the element protection control 1 which will be described only briefly in the following. The disclosures of GB-A-2 194 099, GB-A-2 248 724, GB-A-2 283 155 and GB-A-2 283 156 are incorporated herein by reference and the disclosure of British Patent Application No. 9522594.2 is incorporated into this description by provision of the appended copy. The element protection control 1 provides for the supply of electric current through the control to the heating element of an electrically powered water heating vessel or the like to which the control is affixed, subject to the condition of a bimetallic blade 2 of the control. The bimetallic blade 2 is held in close thermal contact with the heating element and in response to an element overtemperature condition is arranged to open a set of switching contacts within the control thereby to interrupt the supply of electric current through the control. The bimetallic blade 2 is snap-acting in its operation and acts upon a push-rod to open the switching contacts. A secondary level of protection is afforded by mounting the bimetallic blade 2 on a carrier 3 which is formed of a plastics material having a predetermined melting temperature, the carrier being under spring pressure in use of the control and being arranged so that in the event, however unlikely, of the bimetallic blade 2 failing to operate so * that the heating element temperature continues to rise the carrier will begin to soften and will deform under its spring pressure so enabling a set of spring contacts to open within the control. Further details of the general construction and operation of the control 1 will become clear from consideration of the above- referenced specifications. The appliance power connector 4 shown in Figure 2 is an appliance connector inlet part of a plug-and-socket type cordless connection system substantially as described in WO 94/06185 with reference to Figures 7 to 11 thereof. More particularly, the appliance connector inlet part 4 is similar in its construction to the part 130 shown in Figure 8B of the drawings of WO 94/06185 and is adapted to be mated with a complementary plug or appliance connector part 23 (see Figure 3 of the accompanying drawings) which is substantially as shown in Figure 9 of WO 94/06185, the appliance connector and appliance connector inlet parts being configured to enable relative rotation between the two parts throughout a full .360° of rotation. The appliance connector inlet part 4 comprises a generally cylindrical cup-shaped member 5 formed of moulded plastics material and having a central pillar (not shown) formed with a central opening. An earth or ground terminal is provided centrally of the opening, a neutral terminal is provided in the side wall of the opening and a live terminal is provided on the outside wall of the pillar. As shown in Figure 2 which shows the cup-shaped appliance connector inlet part 4 in inverted position, the earth, neutral and live terminals are connected to respective spade or tab terminals 6, 7 and 8. The element protection control 1 of Figure 1 and the appliance connector inlet part 4 of Figure 2 are adapted and arranged to be directly electrically coupled to each other in the manner described in aforementioned British Patent Application No. 9522594.2. As described therein the element protection control 1 and the appliance connector inlet part 4 may be successfully mated with each other with the terminal parts 7 and 8 of the latter engaged in recesses of the former throughout a range of relative positions and relative orientations of the two parts. This is advantageous in that it facilitates manufacture to larger tolerances. Furthermore, again as described in British Patent Application No. 9522594.2, the element protection control 1 may be coupled on top of the appliance connector inlet part 4, thereby enabling a liquid heating vessel to be designed with a smaller diameter than would otherwise be possible, or the two parts may be adapted to be interconnected in side-by-side relationship thus providing a lower overall height than the 'on top' configuration. Referring to Figure 3 there is shown a cordless liquid heating appliance 10, such as a cordless kettle, embodying the present invention. The appliance 10 has a plastics walled vessel 11 and a substantially planar electrical heating element 12 provided as a bottom wall of the vessel 11. The heating element 12 is supported on an inwardly projecting ledge or seat 13 of the vessel 11 and is sealed thereto to be water-tight by means of a ring seal 14. The heating element 12 is made of stainless steel to prevent corrosion occurring on the upper face 15 thereof. The lower face 16 of the heating element 12 has a layer of aluminium spun thereon to improve the distribution of heat across the element 12, and also to provide a mounting surface for the appliance controls. A resistance heating element (not shown) is clenched into the aluminium layer in a manner known per se. At a central region of the lower surface 16, two spaced-apart stud formations 17 are provided for fixing a pair of elongate mounting brackets 18 to the heating element 12. Only a single formation 17 and mounting bracket 18 can be seen in Figure 3 because the other formation 17 and bracket 18 are provided directly behind those shown in Figure 3 and are not visible in the side view of this Figure. The element protection control 1 is secured by rivets for example to one end of each of the mounting brackets 18 so as to enable the bimetal 2 and the plastics material carrier 3 to be located in close thermal contact with the underside of the heating element 12, the rivets passing through the holes 30 provided in the control 1. Power is supplied to the element protection control 1 by way of the appliance connector inlet part 4 which is directly electrically coupled to the control 1 in the previously mentioned 'on top' configuration and, dependent upon the condition of the control, is transferred through the control and to electrical terminations of the heating element by means of electrical conductors. The appliance connector inlet part 4 is mounted to the other ends of the elongate mounting brackets 18, the brackets 18 being so shaped as to support and secure the inlet part 4 in operative relationship with the element protection control 1. However, it is also possible for the mounting brackets to be so shaped as to mount the element protection control 1 and the inlet part 4 in the previously mentioned side-by-side configuration. The connector inlet part 4 is provided on opposite sides thereof with mounting lugs 19 (see Figure 2) . The elongate mounting brackets 18 include through-holes 20 at the ends thereof which are adapted to align with the mounting lugs 19 of the inlet part 4 when the latter is positioned in the base of the appliance 10. Screws 21 pass through the holes 20 and into the mounting lugs 19 to fix the inlet part 4 to the mounting brackets 18. A bottom cover 22 of the appliance 10 is also secured to the mounting brackets 18 by the screws 21 which pass through apertures in the cover 22 which are aligned with the mounting lugs 19. The bottom cover 22 engages the inwardly projecting ledge 13 of the vessel 11, and the arrangement is such that the effect of securing the bottom cover 22 to the mounting brackets 18 is to pull the heating element 12 down onto the ring seal 14. Accordingly, when the appliance 10 is thus assembled, the heating element 12 is effectively sealed with respect to the interior of the vessel 11. The provision of mounting lugs 19 on the inlet part 4 is particularly advantageous because it obviates the need for the provision of a specially formed plastics moulding as is required ' in the aforementioned recently produced cordless electric kettle. In addition, the reduced number of components required for assembly of the appliance advantageously reduces the cost of the appliance. The through-holes 20 in the mounting brackets 18 are oversized (elongate) so as to allow relative movement of the connector inlet part 4 and the bottom cover 22 with respect to the heating element 12. The bottom cover 22 is always accurately aligned with the connector inlet part 4 but may be positionally adjusted within the clearance in the through-holes 20 during assembly to accommodate tolerances in the heating element manufacture. Figure 3 shows the cordless appliance 10 set upon its base 24 with the complementary base connector part 23 of the cordless connection system engaged with the appliance connector inlet part 4. The base connector part 23 is substantially as described in WO 94/06185. Having thus described the present invention by reference to a specific embodiment, it is to be well appreciated that modifications and variations thereto are possible without departure from the spirit and scope of the present invention as set forth in the appended claims. For example, the present invention is not limited to the herein described kind of element protection control and is not limited to the herein described kind of cordless connection system. In fact, the present invention could be readily applied to a corded rather than a cordless appliance, i.e. an appliance in which power is supplied to the appliance connector inlet via a flexible power cord. In addition, whereas the above described embodiment uses two mounting brackets, these could readily be replaced by a single mounting bracket performing the same function. The invention furthermore is not limited to use with planar electric heating elements of the described kind, but could also be used with other kinds of planar electric heating elements such as those of the kind which comprise a substrate having a resistance heating track or layer formed thereupon. One such element which has been proposed comprises a stainless steel substrate having an electrically insulating layer formed on one side thereof, a resistance heating track or layer formed on the electrically insulating layer and a further electrically insulating layer formed over the resistance heating track or layer. As disclosed in GB-A-2 283 156, openings can be provided in the last-mentioned electrically insulating layer to provide power supply terminations of the heating element, and the element protection control can be formed with spring terminals arranged to contact said power supply terminations when the control is operatively juxtaposed with the heating element. There follows a copy of British Patent Application No. 9522594.2 as an integral and essential part of the foregoing description. APPENDIX: Copy of British Patent Application No. 9522594.2 Field of the Invention: This invention concerns improvements relating to electrically powered water heating appliances and the like and to controls therefor. Examples of the kind of water heating appliances to which the present invention may be applied are electric kettles and hot water jugs, urns, pans, laboratory equipment etc., and in the following the invention will be described with particular reference to electric kettles and hot water jugs though it is to be understood that the invention is not limited to such an application. Background of the Invention: Controls for electrically powered water heating appliances such as kettles and hot water jugs are well known which operate to switch off the appliance in the event of an overtemperature condition arising at the heating element of the appliance, for example because of the appliance having been switched on empty or being allowed to boil dry; such controls are commonly referred to as element protection controls. Other controls are well known which operate to switch off the appliance (or at least substantially reduce the APPENDIX: Copy of British Patent Appln. No. 9522594.2 supply of power to the appliance heating element) when water being heated in the appliance comes to the boil; such controls commonly operate by sensing the generation of steam in the appliance and are commonly referred to as steam sensor controls. Both element protection controls and steam sensor controls generally incorporate their own thermal sensors, commonly a bimetallic element, and element protection controls are known which include some form of secondary or back-up protection arranged to operate in the event, however unlikely, of failure of the primary control. An exemplary element protection control is described in GB-A-2 194 099 with reference to Figs. 3A, 3B and 3C thereof and a modified form of such control is described in GB-A-2 248 724. An exemplary steam sensor control is described in GB-A-2 212 664 with reference particularly to Figs. 3A to 3M thereof. In GB-A- 2 283 155 there is described a single sensor combined element protection and steam sensor control which makes use of a modified form of the element protection control of GB-A-2 194 099 (See Fig. 2 of GB-A-2 283 155) in combination with an enclosure as originally proposed in GB-A-1 143 834, the element protection control being disposed at a specific APPENDIX: Copy of British Patent Appln. No. 9522594.2 location on the dry side of a generally planar heating element located in the bottom of a water heating vessel and the enclosure being located on the wet side of the element opposite to the location of the element protection control. The enclosure has openings so that it fills with water when the vessel is filled, and is arranged so that when water boils in the vessel the steam that is generated expels the water from the enclosure thus giving rise to a local element overtemperature condition sensible by the element protection control. By virtue of this arrangement the two functions of element overtemperature protection and steam sensing can be performed by means of a single control. Whilst electric kettles and other water heating appliances have conventionally been corded, that is to say arranged to be connected to an electric socket outlet by means of an electric cord (or cable) terminated with appropriate plug-and-socket type terminations, in recent years so-called cordless appliances have been popular in which power is supplied to the appliance proper via a base unit coupled to the electrical supply, the appliance proper and the base unit having complementary electrical connector parts adapted to provide appropriate APPENDIX: Copy of British Patent Appln. No. 9522594.2 electrical connections through the base unit to the heating element in the appliance proper when the latter is seated on the base. In GB-A-2 241 390 and GB-A-2 236 220 there are described exemplary connection systems for cordless electrical appliances, and in WO 94/06185 there is described a particularly advantageous connection system for cordless appliances which avoids the requirement arising with the systems of GB-A-2 241 390 and GB-A-2 236 220 that the appliance proper has to be particularly orientated relative to the base before the connector parts can be engaged with each other. The connection system of WO 94/06185 provides for mating interconnection of the appliance proper with its base throughout a full 360°, or almost a full 360°, of relative rotation of the two connector parts. Disclosed in WO 94/06185 with reference to Figs. 7 to 11 thereof is a connection system for a cordless electrical appliance in which a plug part of the connection system, shown in Fig. 8B, is integrally formed with an element protection control in accordance with the teachings of GB-A-2 194 099. The problem with such an arrangement, however, is that it suffers from a lack of flexibility, the integration of the element protection control with the connector plug APPENDIX: Copy of British Patent Appln. No. 9522594.2 part limiting the ability of the appliance designer to design appliances with freedom and furthermore imposing severe tolerance constraints upon the manufacturers of such appliances. Objects and Summary of the Invention: The present invention has as its object the solution or at least substantial reduction of the aforementioned problem arising with integrated element protection controls and cordless connection systems. According to the present invention, in one of its aspects, a combined element protection control and cordless connection system for a water heating appliance or the like is provided in which the element protection control and the appliance connector part of the cordless connection system are formed as separate items having electrical connector parts adapted to couple together, the electrical connector parts preferably being such as to enable effective interconnection of the two items within a range of relative positions thereof. In an exemplary embodiment of the present invention as thus defined, the socket part of a cordless connection system according to the teachings of WO 94/06185 and an element protection control according to the teachings of GB-A-2 194 099 are APPENDIX: Copy of British Patent Appln. No. 9522594.2 provided with interconnectable electrical connector parts adapted to be plugged together, a pair of spade terminals (plugs) being provided on one of the two and accommodating receptacles (sockets) being provided on the other. The receptacles (sockets) preferably incorporate spring terminals designed to enable satisfactory electrical interconnection to be established even when the connector socket part and the element protection control are somewhat out of proper alignment with each other or otherwise somewhat improperly positioned relative to each other, for example as the result of tolerances arising in the manufacture of the accompanying appliance. Described hereinafter in detail are variants of the abovementioned embodiment which provide for the mounting of the element protection control on top of the socket part of the cordless connection system or side-by-side with the socket part, such variants accommodating different appliance designs and providing the appliance designer with increased flexibility. The electrical connector parts that are provided on the socket part of the cordless connection system and/or on the element protection control may be such as to enable the respective items to be used selectively in one or other of the on top and side-by APPENDIX: Copy of British Patent Appln. No. 9522594.2 -side variants. The present invention also extends to an electrically powered water heating appliance incorporating a cordless connection system and an element protection control according to the teachings hereof. The invention is particularly, though not exclusively, applicable to water heating appliances wherein the electrical heating element of the appliance is of the planar type, for example as is described in GB-A-2 283 155. The above and further features of the present invention are set forth with particularity in the appended claims and will become clear from consideration of the following detailed description of exemplary embodiments which are illustrated in the accompanying drawings. Description of the Drawings: Figure 1 is a perspective view of an element protection control generally in accordance with the teachings of GB-A-2 194 099 and GB-A-2 248 724 and specially configured for the present invention; Figure 2 is a perspective view of one part of a cordless connection system generally in accordance with the teachings of WO 94/06185 and specially configured for the present invention; APPENDIX: Copy of British Patent Appln. No. 9522594.2 Figure 3 is a perspective view showing the element protection control of Figure 1 connected to the top of the connection system part of Figure 2; Figure 4 is a plan view of the combined element protection control and connection system part of Figure 3; Figure 5 is an underplan view of the Figure 3 combination; Figure 6 is a part sectional side elevation view showing how the element protection control of Figure 1 and the connector system part of Figure 2 are adapted to be interconnected; Figure 7 is an enlarged showing of part of Figure 6? Figure 8 is a perspective view of a modified form of the element protection control of Figure 1; Figure 9 is a perspective view of a modified form of the connection system part of Figure 2 ; Figure 10 is a perspective view showing the element protection control of Figure 8 connected to the connector system part of Figure 9 in a side-by- side configuration; Figure 11 is a plan view of the combined element protection control and connector system part of Figure 10; APPENDIX: Copy of British Patent Appln. No. 9522594.2 Figure 12 is an underplan view of the Figure 10 combination; Figure 13 is a part sectional side elevation view showing how the element protection control of Figure 8 and the connector system part of Figure 9 are adapted to be interconnected; Figure 14 is an enlarged showing of part of Figure 13 ; Figures 15 and 16 are views similar to Figures 2 and 6 showing a modified form of the embodiment of Figures 1 to 7 ; and Figures 17 and 18 are views similar to Figures 9 and 13 showing a modified form of the embodiment of Figures 8 to 14. Detailed Description of the Embodiments: Referring first to Figures 1 to 7 of the accompanying drawings, these illustrate a first embodiment of the present invention. An element protection control 1 (Figure 1) is a modified form of the control that is described in GB-A-2 194 099 with reference to Figures 3A, 3B and 3C thereof, or a modified form of the control that is described in GB-A-2 248 724, or a modified form of the controls that are described in GB-A-2 283 155 and GB-A-2 283 156. Reference should be had to the referenced APPENDIX: Copy of British Patent Appln. No. 9522594.2 specifications for a full understanding of all aspects and advantages of the subject control which will be described only briefly in the following. The element protector control 1 provides for the supply of electric current through the control to the heating element of an electrically powered water heating vessel or the like to which the control is affixed, subject to the condition of a bimetallic blade 2 of the control. The bimetallic blade 2 is held in close thermal contact with the heating element and in response to an element overtemperature condition is arranged to open a set of switching contacts within the control thereby to interrupt the supply of electric current through the control. The bimetallic blade 2 is snap-acting in its operation and acts upon a push-rod to open the switching contacts. A secondary level of protection is afforded by mounting the bimetallic blade 2 on a carrier 3 which is formed of a plastics material having a predetermined melting temperature, the carrier being under spring pressure in use of the control and being arranged so that in the event, however unlikely, of the bimetallic blade 1 failing to operate so that the heating element temperature continues to rise the carrier will being to soften and will deform under its APPENDIX: Copy of British Patent Appln. No. 9522594.2 spring pressure so enabling a set of spring contacts to open within the control. Further details of the general construction and operation of the control 1 will become clear from consideration of the above- referenced specifications. Figure 2 shows the socket or appliance connector inlet part 4 of a plug-and-socket type cordless connection system substantially as described in WO 94/06185 with reference to Figures 7 to 11 thereof. More particularly, the appliance connector inlet part 4 is similar in its construction to the part 130 shown in Figure 8B of the drawings of WO 94/06185 and is adapted to be mated with a complementary plug or appliance connector part substantially as shown in Figure 9, the appliance connector and appliance connector inlet parts being configured to enable relative rotation between the two parts throughout a full 360° of rotation. The appliance connector inlet part 4 comprises a generally cylindrical cup-shaped member 5 formed of moulded plastics material and having a central pillar 6 formed with a central opening 7 (see Figure 5) . An earth or ground terminal 8 is provided centrally of the opening 7, a neutral terminal 9 is provided in the side wall of the opening 7 and a live terminal 10 is provided on the outside APPENDIX: Copy of British Patent Appln. No. 9522594.2 wall of the pillar 6. As shown in Figure 2 which shows the cup-shaped appliance connector inlet part 4 in inverted position, the earth, neutral and live terminals 8, 9 and 10 are connected to respective spade or tab terminals 11, 12 and 13, the neutral and live tab terminals 12 and 13 extending upwardly from the part 4. The element protector control 1 of Figure 1 is adapted and arranged to be plugged onto the appliance connector inlet part 4 of Figure 2 in the manner shown in Figure 3 and in more detail in Figures 6 and 7. As can be seen most clearly in Figures 6 and 7 , the element protector control 1 is formed with a pair of recesses 15 in each of which there is provided a looped spring metal part 16. An opening 17 is provided in the bottom of each recess 15 for admitting thereto a respective one of the neutral and live terminals 12, 13 of the appliance connector inlet part 4 when the control 1 and the appliance connector inlet part 4 are juxtaposed as shown in Figure 3, and with the terminals 12, 13 thus received in the recesses electrical connection is made between the terminals 12,13 and the looped spring metal parts 16 which bear against the terminals with a substantial force. By virtue of these connections, electric current is APPENDIX: Copy of British Patent Appln. No. 9522594.2 enabled to flow from the connector part 4 through the tab terminals 12,13 and the spring metal parts 16 into the control. The form of the spring metal parts 16, the size of the recess 15 and of the openings 17, and the relative size of the terminal parts 12 and 13 are such as to enable the element protector control 1 and the appliance connector inlet part 4 to be successfully mated with each other throughout a range of relative positions and relative orientations of the two parts. As mentioned hereinbefore, this is advantageous in that it enables the inevitable manufacturing tolerances that arise with water heating vessels and the like to be accommodated with ease. With the mated appliance connector inlet part 4 and element protector control 1 affixed to the heating element of a water heating vessel, for example, the appliance connector inlet part 4 is able to be mated with an appliance connector part as shown in Figure 8A of WO 94/06185. Referring now to Figures 8 to 14 of the accompanying drawings, shown therein is an alternative embodiment of the present invention which is the same as the above-described embodiment except that the appliance connector inlet part and the element protection control are adapted to be interconnected in APPENDIX: Copy of British Patent Appln. No. 9522594.2 side-by-side relationship thus providing a lower overall height than the "on top" first embodiment. The same reference numerals are used in Figures 8 to 14 as are used to designate like parts and functionally similar parts in the first embodiment, and it will be seen that in Figure 9 the neutral and live terminals 12 and 13 extend horizontally, whereas they extend vertically in Figure 2, and in Figures 13 and 14 that the terminals 12 and 13 of the appliance connector inlet part 4 access the springs 16 of the element protection control 1 via openings 17 in the side of the control rather than underneath the control as in Figures 6 and 7. In all other respects the embodiment of Figures 8 to 14 is the same as the embodiment of Figures 1 to 7. Referring now to Figures 15 and 16 and Figures 17 and 18 these show respectively modifications of the first and second embodiments described in the foregoing and again the same reference numerals are used in Figures 15 to 18 as were used to designate like parts in Figures 1 to 14. A comparison of Figures 15 and 16 with Figures 2 and 6 will show that the modifications comprise the use of push-fit terminal members for defining the neutral and live terminals 12 and 13, the push-fit terminal members SUBSTITUTESHEET(RULE26J APPENDIX: Copy of British Patent Appln. No. 9522594.2 being separate components which push-fit onto neutral and live spade or tab terminal parts, similar to the earth terminal 11, which are provided on the appliance connector inlet part 4, and the use of a differently shaped spring 16 within the element protection control 1. In the modified embodiment of Figures 17 and 18, differently shaped push-fit terminal members are provided on the neutral and live tab terminals. The basic appliance connector inlet part 4 is the same in Figure 15 as in Figure 17 and the use of differently shaped push-fit terminal members enables "on top" and "side-by-side" configurations to be accommodated using the same element protection control 1 and the same basic appliance connector inlet part 4. It will be seen from the foregoing explanations that the described arrangements accommodate relative movements between the appliance connector inlet part and the element protection control, such movements being achieved by sliding contact between the tab terminals of the appliance connector inlet part and the springs of the element protection control and/or by flexing of one or both of the tabs and the springs. The two necessary interconnections, neutral and live, can move independently to provide any necessary angular movement. The earth terminal tab of the APPENDIX: Copy of British Patent Appln. No. 9522594.2 appliance connector inlet part may be attached to the appliance by means of a flexible lead or directly to the appliance, as by riveting for example, and electrical connections between the element protection control and the heating element may be made with flexible leads coupled to the tab terminals 20 of the control 1 by means of quick connect receptacles or, with the control appropriately modified as described in GB-A-2 285 156 for example, by means of spring connections. Connections to a steam control may be similarly made. Having thus described the present invention by reference to particular embodiments, it is to be well appreciated that modifications and variations thereto are possible without departure from the spirit and scope of the present invention as set forth in the appended claims. For example, the present invention is not limited to the herein described kind of element protection control and is not limited to the herein described kind of cordless connection system. APPENDIX: Copy of British Patent Appln. No. 9522594.2 CLAIMS: 1. In or for an electrically powered heating appliance, a combined element protection control and appliance connector inlet part of a cordless connection system, said element protection control and appliance connector inlet part being formed as separate items having electrical connector parts adapted to be coupled together. 2. The combination of claim 1 wherein said electrical connector parts comprise male terminal parts on one of said items and female terminal parts on the other. 3. The combination of claim 2 wherein tab terminals on one of said items are adapted to be received in terminal recesses in the other. 4. The combination of claim 3 wherein terminal springs are provided in said recesses. 5. The combination of any preceding claim wherein said electrical connector parts are such as to enable effective interconnection of the two items within a range of relative positions thereof. APPENDIX: Copy of British Patent Appln. No. 9522594.2 6. The combination of any preceding claim wherein said element protection control comprises a bimetal mounted in or on a thermally collapsible carrier and the action of the bimetal is arranged to provide a primary control function and the thermally-induced collapse of the carrier is arranged to provide a secondary or back-up control function. 7. The combination of any preceding claim wherein said appliance connector inlet part is adapted for engagement with a complementary appliance connector part enabling engagement of the two connector parts substantially irrespective of the relative rotational orientation thereof in the plane transverse to the engagement direction of the parts. 8. The combination of claim 7 wherein said appliance connector inlet part and said appliance connector part are generally coaxially arranged. 9. The combination of any preceding claim wherein said element protection control is substantially as herein described with reference to Figure 1, 8 or 16 of the accompanying drawings. APPENDIX: Copy of British Patent Appln. No. 9522594.2 10. The combination of any preceding claim wherein said appliance connector inlet part is substantially as herein described with reference to Figure 2, 9, 15 or 17 of the accompanying drawings. 11. The combination of any preceding claim affixed to an electric heating element. 12. The combination of claim 11 wherein said electric heating element comprises a generally planar heating element having the combined element protection control and appliance connector inlet part affixed to one side thereof. 13. The combination of any preceding claim further including a complementary appliance connector part of said cordless connection system. 14. An electrical appliance including the combination claimed in claim 13. APPENDIX: Copy of British Patent Appln. No. 9522594.2 Abstract of the Disclosure A cordless electrical appliance such as an electrical kettle has an element protection control combined with an appliance connector inlet part of the cordless connection system of the appliance, the element protection control and the appliance connector inlet part being separate items which plug into each other by way of connections providing for a degree of flexibility as regards the relative positions of the parts when they are plugged into each other. By virtue of this arrangement manufacturing tolerances in electrical appliances to which the subject combination is to be fitted can readily be accommodated. (Figure 10) . END OF APPENDIX

Claims: CLAIMS : 1. A combination of an element protection control, an appliance power connector and a mounting bracket for an electrically powered heating appliance, said element protection control and said appliance power connector each being coupled to said mounting bracket for mounting to a heating element of said appliance. 2. A combination as claimed in claim 1, wherein said mounting bracket includes means for permitting adjustment of the relative mounting position between the appliance power connector and the heating element. 3. A combination as claimed in claim 2, wherein said adjustment means comprises an elongate through-hole for co-operating with a fastener extending through said hole. 4. A combination as claimed in any preceding claim wherein the mounting bracket comprises an elongate member which is arranged at one end thereof to be coupled to the element protection control and at the other end thereof to be coupled to the appliance power connector. 5. A combination as claimed in any preceding claim, wherein the mounting bracket is arranged to mount said element protection control on top of said appliance power connector or in side-by-side relationship with said appliance power connector. 6. A combination as claimed in any preceding claim, wherein the appliance power connector comprises at least one mounting lug for receiving a fastener. 7. A combination as claimed in any preceding claim, wherein the element protection control and the appliance power connector comprise electrical connector parts adapted to be coupled together so as to enable effective interconnection therebetween within a range of relative positions thereof. 8. A combination as claimed in any preceding claim, wherein said element protection control comprises a bimetal mounted to a thermally collapsible carrier, the action of the bimetal is arranged to provide a primary control function, and the thermally-induced collapse of the carrier is arranged to provide a secondary or back-up control function. 9. A combination as claimed in any preceding claim wherein said appliance power connector comprises an inlet part of a cordless connection system adapted for engagement with a complementary connector part enabling engagement of the two connector parts substantially irrespective of the relative rotational orientation thereof in the plane transverse to the engagement direction of the parts. 10. A combination as claimed in claim 9 wherein said inlet part and said complementary connector part are generally coaxially arranged. 11. A combination substantially as described herein with reference to the accompanying drawings. 12. A combination as claimed in any preceding claim affixed to an electric heating element. 13. A combination as claimed in claim 12 wherein said electric heating element comprises a generally planar heating element having the element protection control, appliance power connector and mounting bracket affixed to one side thereof. 14. An electrically powered heating appliance comprising a liquid heating vessel and a combination as claimed in claim 13. 15. An electrically powered heating appliance as claimed in claim 14 wherein said planar heating element is sealingly secured in said liquid heating vessel by virtue of a bottom cover of said vessel being secured to said mounting bracket.

Inventors: BROOK STEPHEN ROGER, O'NEILL ROBERT ANDREW, WHITE IAN GEOFFREY, BROOK, STEPHEN, ROGER, O'NEILL, ROBERT, ANDREW, WHITE, IAN, GEOFFREY
Applicants: BROOK STEPHEN ROGER, ONEILL ROBERT ANDREW, OTTER CONTROLS LTD, WHITE IAN GEOFFREY, BROOK, STEPHEN, ROGER, O'NEILL, ROBERT, ANDREW, OTTER CONTROLS LIMITED, WHITE, IAN, GEOFFREY
Application year: 1996
Main classification: A47J27
IPC codes: A47J27