AU718209B2 - Connection systems for cordless appliances - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant(s): OTTER CONTROLS LIMITED Invention Title: CONNECTION SYSTEMS FOR CORDLESS APPLIANCES

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The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 CONNECTION SYSTEM FOR CORDLESS APPLIANCES The present application is a divisional application of Australian Patent Application No. 49703/93 the disclosure of which is incorporated herein by reference.

Field of the Invention: This invention generally concerns improvements relating to electrical appliances and connectors therefor and more particularly, though not exclusively, relates to an improved connection system for so-called "cordless" electrical appliances in which power is supplied to an appliance proper via a base unit coupled to the electrical supply. Examples of such cordless appliances are electric kettles and hot water jugs and electric smoothing irons, but the connection system of the present invention is not limited to use in such appliances and, moreover, is not limited to use with cordless appliances.

Background of the Invention: 9 Cordless appliances generally have a socket outlet provided in or on the base unit and a mating o oconnecting inlet in or on the appliance proper, and 25 generally require fairly precise alignment between these two parts in order to connect the appliance proper to the base. The connecting inlet of the appliance proper commonly comprises a set of male terminal pins which are adapted to mate with a complementary set of female 30 terminals provided in a shrouded portion of the base unit, and the base unit terminals are commonly provided in an upstand formed on the base unit and adapted to locate in a generally complementary recess formed in the body of the appliance proper for providing the degree of alignment between the respective parts that is necessary to ensure correct mating of the two parts of the connection system.

C:\Mcooper\Kep\speci\b9038.98.doc 27/01/00 3 An exemplary cordless connection system of this kind is disclosed in our British Patent Application No. 9102099.0 (GB-A-2 241 390). An alternative system in which the terminal pins are provided in the base unit and complementary spring terminals are provided in the appliance proper is disclosed in our British Patent Application No 9018502.6 (GB-A-2 236 220).

The requirement that the appliance proper and the base unit should mate with each other only in a predetermined single orientation is a restriction upon the freedom of the appliance designer to achieve the desired product form and also presents some inconvenience to users of the appliance. It has previously been recognised that an excessive requirement for alignment of the appliance proper with the base unit is undesirable and in British Patent No GB-B-2 221 104 (Strix Ltd) there is disclosed a cordless connection system which is generally conventional but is adapted to accommodate a degree of initial misalignment of the appliance proper with the base.

It is an object of the present invention to overcome one or more of the aforementioned problems.

According to the present invention there is provided a cordless water boiling appliance including a vessel having a heating element for heating water in the 25 vessel to boiling, a base for connection to an electrical power supply, and electrical connector provided on the base and a complementary electrical connector provided on the vessel, said connectors permitting the heating element in the vessel to be powered via the base when the vessel is seated on the base and said connectors are interconnected, and said connectors permitting the vessel to be operatively coupled to the base throughout a full 3600 of relative rotational orientation between the vessel and the base.

In an embodiment of the present invention, which will be described in detail hereinafter, it is preferred that there is further provided an overtemperature disconnect device associated with said heating element of H:\MCooper\Kep\Speci\69038.98,doc 24/01/00 4 disconnecting the heating element from its power supply in an element overtemperature situation, whereby, said heating element is powered in dependence upon the condition of said overtemperature disconnect device.

Preferably, the electrical connector that is provided on the base has terminations on its electrical terminal parts for the coupling thereto of the conductors of the electrical power supply.

Preferably, the electrical connectors provided on the base and on the vessel comprise live, neutral and earth terminal parts arranged such that the co-operating earth terminal parts engage first when the vessel is placed on its base and disengage last when the vessel is removed from its base.

Preferably, said electrical connectors are shaped externally to facilitate their mating by guiding them together once they are imprecisely engaged.

Preferably, the electrical connector that is provided on the base is a shuttered electrical connector.

Preferably, said connector system has interconnecting male and female parts, said female S S connector part having a plurality of movable shutter •elements having surfaces which together define a concavity for receiving the male connector part, and a releasable 25 locking member holding said plurality of shutter elements "i in closed condition until released, the arrangement being such that the insertion of the male connector part into said cavity serves to release said locking member and to S urge said shutter elements open for enabling electrical terminals of said male connector part to engage conductors Sprovided in the female connector part.

Preferably, said concentric electrical parts include, on one of the two connectors, first and second annular terminals spaced concentrically with respect to each other and a third terminal within the innermost one of the first and second terminals, the other of the two connectors having complementary terminal parts adapted to H:\MCooper\Keep\Speci\6 9 038.98 .doc 24/01/00 5 engage the terminal parts of the first mentioned connector.

Preferably, the electrical connectors that are provided on the base and on the vessel are generally centrally positioned under the vessel and on the upper side of the base.

The foregoing and further aspects of the present invention are set forth in the appended claims and will best be understood 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 an axially exploded view of an exemplary connector socket part constructed and arranged in accordance with an embodiment of the present invention; Figure 2A shows the connector socket part of Figure 1 in assembled condition and with its component parts shown in enlarged sectional side elevation view, and Figure 2B shows a sectional side elevation view of an exemplary connector plug part adapted to be mated with the socket part of Figure 2A; S: Figure 3 shows the connector socket and plug 25 parts of Figure 2A and 2B in engaged condition; Figure 4 is a view similar to Figure 2A and illustrating the operation of the shutter mechanism incorporated into the connector socket part; and Figure 5 is a perspective view of the connector socket part illustrating water shedding features incorporated into its upper parts.

Detailed Description of the Embodiment: Referring to Figures 1 and 2A, the connector socket part of an embodiment is generally designated 101 and is formed of a number of generally circularly- H:\MCooper\Keep\S~epi\69038.98.doc 24/01/00 6 cylindrical components which assemble together to form a socket having rotational symmetry in a plane transverse to the axial direction of the components, which corresponds to the direction in which the plug and socket parts of the connector are moved to mate the two connector parts. The components of the socket part comprise a moulded plastics main housing 102, a moulded plastics shutter 103, first and second electrical contact rings 104 and 105, a spiral spring 106, a moulded plastics base 107 and a spring contact finger 108.

As best shown in Figure 2A, the larger diameter contact ring 105 fits within an upper part 109 of the main housing 102 which is dimensioned to make close contact with an outwardly turned upper edge 110 of the contact ring 105 which abuts a shoulder 111 formed in the main housing 102.

The shutter 103 fits loosely within the main housing 102 so as to be axially moveable with a degree of freedom to tilt as will be explained below, and comprises an annular head portion 112, a cylindrical portion 113 and an outwardly extending flange 114 which abuts the lower edge 115 of the contact ring 105 to prevent the shutter from moving out of the main housing. The main housing 102, with the contact ring 105 and shutter 103 installed, fits onto the base 107 with a cylindrical lower part 116 of the main housing 25 fitting closely over an upstanding cylindrical part 117 of the base and a hollow central post 118 of the base extending upwards through the central opening 119 provided in the head of the shutter 103.

The lesser diameter contact ring 104 fits tightly onto an appropriately dimensioned part 120 of the post 118 with its lower edge 121 abutting a shoulder 122 provided on the post, and the upper edge 123 of the ring 104 is turned •e inwardly so as to conform to the lower extremity of an undercut portion 124 of the post 118. The spring contact finger 108 extends within the central hollow 125 of the post 118 and an opening 126 is provided in the top of the post for admitting a terminal pin to the interior of the H:\MCoope\Keep\Speci\69038.

9 8.doc 24/01/00 7 post for electrically contacting the contact finger 108.

Figure 2B shows an exemplary form of overtemperature disconnect device, suitable for use with a water boiling appliance for example, the device including a connector plug part adapted for use with the connector socket part of Figures 1 and 2A. The connector plug part is generally designated 130 and comprises a plastics moulding formed with an outer circularly-cylindrical wall 131 dimensioned to make a relatively close fit over the upper part 109 of the main socket housing 102, and an inner circularly-cylindrical wall 132 dimensioned to make a relatively close fit into the space occupied by the shutter 103 of the socket between the central post 118 and the radially inner surface of the socket part 109, the lower edge 133 of the inner wall 132 serving to depress the shutter 103 when the plug is correctly inserted into the socket in the axial direction. A central, axially extending terminal pin 134 is mounted in the plug part 130 and is adapted to extend into the opening 126 provided in the top of the central post 118 of the connector socket and to make electrical contact with the spring finger 108, and first and second spring terminals 135 and 136 each carrying an electrical contact at its free end are cantilevered g: within the plug part 130 in registry with respective 25 grooves 137 and 138 provided in the outer and inner surfaces respectively of the inner wall 132 of the plug, the grooves 137 and 138 providing space for the respective spring terminals 135 and 136 to flex.

Figure 3 shows the connector plug part 130 of Figure 2B mated with the connector socket part 101 of *Figure 8A, the mating of the two parts being effected by moving them together in the axial direction as indicated by the arrow shown in Figure 2B. It will be seen from Figure 3 that the central terminal pin 134 of the plug part makes electrical contact with the spring finger 108 of the socket part, that the contact provided at the free end of spring terminal 135 of the plug part makes electrical contact with H:\MCooper\Keep\Speci\6 9

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98 ,doc 24/01/00 8 the outer contact ring 105 of the socket part, and that the contact provided at the free end of spring terminal 136 of the plug part makes electrical contact with the inner contact ring 104 of the socket part. The shutter 103 in the socket part is depressed against the bias of the spring 106 by the lower edge 133 of the wall 132 of the plug part, and will be restored to its closed condition as shown in Figure 2A by the action of the spring 106 when the plug part 130 is withdrawn from the socket part 101, abutment of the upper surface of the flange 114 on the shutter 103 with the lower edge 115 of the outer contact ring 105 limiting the range of upward movement of the shutter in the plug socket part.

An undercut 124 (namely a portion of lesser diameter) is provided on the central post 118 of the socket part 101 just above the location of the contact ring 104.

A similar undercut is defined within the upper part 109 of the main socket moulding 102 just above the location of the contact ring 105. The purpose of these undercuts is to prevent the contacts provided on the spring terminals 135 -•and 136 of the plug part dragging on the respective .surfaces of the socket part during insertion and withdrawal of the plug part and possibly leaving metallic tracks on Sthe surfaces. Such tracks would be electrically conductive 25 and would represent an electrical hazard. The undercuts also reduce wear on the electrical contacts which may, for example, be formed of silver. The contact rings 104 and 105 are preferably formed of copper or a copper alloy having a thermal conductivity at least 90% of that of 30 copper and provided with a thick 50m) surface plating of a silver antimony alloy as described in GB-A- 2253097, and the terminal pin 134 may be similarly formed.

It will be seen that the plug and socket parts of the connector of Figures 1 to 5 have rotational symmetry in a plane transverse to the axial direction of their insertion one into the other as depicted by the arrow shown in Figure 2B. Namely, apart from the spring 106 and the H:\MCooper\Keep\speci\69038.98.doc 24/01/00 9 spring terminals 135 and 136, all of the component parts of the plug and socket are generally circular in transverse cross-section, transverse that is to the axial direction.

The fact that this is so enables the plug part of the connector to be introduced into the socket part throughout a full 3600 of relative rotation between the parts.

Referring to Figure 4, this is a view of the socket part of the connector which is very similar to Figure 2A, but illustrates the locking action of the shutter in the event that it is subject to a force which is not applied uniformly throughout the full extent of its annular upper surface. In order to meet safety requirements, it must not be possible to gain access to live parts within the socket by depressing the shutter with a test or human finger and, as shown in Figure 4, the arrangement of the shutter 103 is such that if it is depressed at a single point, as shown by the arrow, then it rocks upon the supporting spring 106 and its lower rim engages the upper edge of the cylindrical upstand 117 which prevents downwards movement of the shutter. The shutter can only be depressed into the socket by application to the top of the shutter of a force which is more or less uniform •000 throughout the annular extent of the shutter head so that the shutter is maintained in coaxial alignment with the 25 socket and its flange 114 can slide down within the cylindrical upstand 117. The underside of the inner wall 132 of the plug part can provide such a uniform force so long as the plug and socket parts are sufficiently well aligned in the axial direction. As shown, the inner edge of the top of the upstand 117 has a chamfer and, by selection of the angle of this chamfer and the radial clearance between the shutter flange 114 and the inner surface of the upstand 117, it is possible to achieve a satisfactory range of angle of approach of the plug to the socket whilst maintaining the electrical safety provided by the shutter.

The engaging surfaces of the shutter and the H:\MCooper\Keep\Spei\69038.98.doc 24/01/00 10 upstand 117, that is to say the surfaces which engage to prevent depression of the shutter when a non-uniform force is applied which causes it to tilt, could be curved so as to have a ball-and-socket type of co-operation allowing smooth disengagement of the locked shutter as the plug is brought into proper alignment for entry into the socket.

By provision of such curved surfaces, the appliance proper part of a cordless appliance could be placed casually onto its base and smooth engagement between the plug and socket parts of the connector system would still be achieved.

Referring now to Figure 5 and back to Figure 2A, it will be seen that the top edge of the main housing 102 of the socket part 101 of the subject connector is provided with shaped castellations 150 designed to allow water to drain from the top surface of the socket whilst providing an inwardly facing guiding surface to enhance the engagement guidance of the plug 130 into the socket. As shown in Figure 2A, the inner surface of each castellation upstand forms part of a female conical annulus which acts 20 to guide the bottom surface 133 of the inner wall 132 of the plug into contact and alignment with the top of the 9 shutter 103, and also serves as a lead in for the contact 9 provided at the end of spring terminal 135. The surfaces between the castellation upstands form part of a male *9 25 conical annulus which slopes outwards and downwards to encourage any water spilled onto the top surface of the shutter to escape between the castellation upstands rather 9 than penetrate to the interior of the socket. The main housing 102 is further provided with a skirt 151 which 30 forms a water shedding feature designed to overlap an aperture in a cordless appliance base, for example, in 9 9 •:go which the socket is mounted.

"While the plug and socket connector as described in the foregoing are particularly intended for use with a cordless electrical appliance, such as a kettle or hot water jug for example, the invention is not limited to such an application and could form the basis of an appliance H:\MCooper\Keep\Speci\69038.98.doc 24/01/00 11 cord set, for example, replacing the standard 10 amp connector currently in use in the UK. The socket of Figures 1 to 5 for example could be fitted with a cable anchorage and cosmetic cover and used with a plug mounted in or on an appliance, or alternatively the plug could be provided with the cable anchorage and cover and used with the socket mounted in or on the appliance. A locking means would preferably be provided to ensure that the shutter spring did not push the plug out of the socket and this could be a simple manual latch arrangement. Such a plug and socket connector would enable very simple and low force engagement and would provide enhanced safety as compared to current 10 amp connectors.

The overtemperature disconnect device shown in Figure 2B is a modified form of the device described in GB- A-2194099 with reference to Figures 3A, 3B and 3C thereof and is illustrated herein in schematic form merely by way of an example of the way in which the plug part of the subject connector could be utilized. As illustrated in 20 Figure 2A hereof the upper ends 161 and 162 of the spring terminals 135 and 136 in the plug portion 130 of the device S- extend into a switch enclosure 160 where they are engaged by respective electrically conductive springs 163 and 164 o. which are biased into engagement with the terminal ends 161 25 and 162 by a moulded plastics material member 165 which corresponds to the thermally-collapsible carrier 121 shown in Figures 3A, 3B and 3C of GB-A-2194099 abovementioned.

Although not shown in Figure 2A, reference to GB-A-2194099 will show that the contact between the springs 163 and 164 30 and the terminal ends 161 and 162 is necessary in order that power can be supplied through the overtemperature disconnect device to an electrical heating element comprising a resistance heating element proper and an element head plate, the head plate of the heating element being shown in Figure 2B at 166. The member 165 stands on the head plate 166 as shown and, in the event of an overtemperature condition, the member 165 thermally deforms H:\MCooper\Keep\Speci\69038.98.doc 24/01/00 12 under the action of the springs 163 and 164 thereby breaking the connections made between the springs 163 and 164 and the terminal ends 161 and 162 and interrupting the supply of power to the heating element. As described in GB-A-2194099, the member 165 can serve to carry a bimetallic element in close thermal contact with the element head plate 166, the bimetallic element serving to open a set of contacts provided in the power supply line to the heating element in the event of an element overtemperature condition, the thermally induced collapse of the member 165 then serving a secondary or back-up function in the event, however unlikely, that the primary protective function provided by the bimetal and its associated contacts set fails to operate.

It will be appreciated that the above-described embodiment is exemplary only and that many modifications and variations are possible without departure from the general ambit of the invention. For example, it would be possible to dispense with either the central terminal pin 134 or one of the spring terminals 135, 136 if there was no requirement for an earth terminal. If the central terminal S. pin 134 was dispensed with, then clearly there would be no •99 need to form the central post 118 of the socket part 101 ?with a hollow interior and the spring terminal 108 could 25 also be eliminated, though it could in some circumstances possibly be advantageous to retain the hollow interior of the central post as a feature for enhancing the water shedding ability of the socket. Other modifications and variations will readily occur to those possessed of 30 relevant skills.

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Claims (34)

1. A cordless water boiling appliance including a vessel having a heating element for heating water in the vessel to boiling, a base for connection to an electrical power supply, and electrical connector provided on the base and a complementary electrical connector provided on the vessel, said connectors permitting the heating element in the vessel to be powered via the base when the vessel is seated on the base and said connectors are interconnected, and said connectors permitting the vessel to be operatively coupled to the base throughout a full 3600 of relative rotational orientation between the vessel and the base.

2. A cordless electrical water boiling appliance as claimed in claim 1 and further including an overtemperature disconnect device associated with said heating element of disconnecting the heating element from its power supply in an element overtemperature situation, whereby, said heating 20 element is powered in dependence upon the condition of said overtemperature disconnect device.

3. An appliance as claimed in claim 1 wherein the electrical connector that is provided on the base has *00: 25 terminations on its electrical terminal parts for the coupling thereto of the conductors of the electrical power S..oo; supply. *.0•00

4. An appliance as claimed in any one of the preceding claims wherein the electrical connectors provided 0 on the base and on the vessel comprise live, neutral and earth terminal parts arranged such that the co-operating earth terminal parts engage first when the vessel is placed on its base and disengage last when the vessel is removed from its base.

An appliance as claimed in any one of the H:\mCooper\Keep\Speci\69038.982doc 24/01/00 14 preceding claims wherein said electrical connectors are shaped externally to facilitate their mating by guiding them together once they are imprecisely engaged.

6. An appliance as claimed in any one of the preceding claims wherein the electrical connector that is provided on the base is a shuttered electrical connector.

7. An appliance as claimed in claim 6 and wherein the electrical connection system has a plug part and a socket part and the shutter is arranged to be locked in the stand alone condition of the plug and socket parts and to be releasable by proper coupling of the plug part with the socket part.

8. An appliance as claimed in claim 7 wherein the shutter is provided in the socket part.

9. An appliance as claimed in claim 6 wherein the electrical connection system has a plug and socket electrical connector wherein a shutter in the socket is displaceable by the plug to permit entry of the plug into the socket only if the shutter has a predetermined disposition relative to the socket, and wherein the plug is 25 insertable into the socket irrespective of the relative rotational orientation of the plug and socket transversely to the direction of insertion of the plug into the socket.

10. An appliance as claimed in claim 6 wherein the electrical connection system has a plug part and a socket part, the plug part being insertable into the socket part by relative movement between the two parts in a predetermined direction irrespective of the relative o:oo rotational orientation of the two parts transversely to 35 said predetermined direction, and the shutter being provided in the socket part and being displaceable therein for admitting the plug part only if the shutter has a H:\MCooper\KeeP\Speci\69038.98.dc 24/01/00 15 predetermined disposition, the shutter being capable of adopting alternative dispositions within the socket part, and the plug part being formed so as to hold the shutter in said predetermined disposition so long as the plug part and socket part are approached to each other in said predetermined direction.

11. An appliance as claimed in claim 10 wherein the socket part has a circularly-cylindrical member within which a shutter having a circular section is axially displaceable so long as the shutter disposition is generally coaxial with the socket part, the arrangement being such that the shutter cannot be displaced within the socket if the shutter disposition is tilted out of coaxiality.

12. An appliance as claimed in claim 11 wherein a portion of the shutter is arranged to engage a portion of the socket to prevent displacement of the shutter into the socket when the shutter disposition is out of coaxiality.

13. An appliance as claimed in claim 12 wherein the shutter has a circularly-cylindrical portion dimensioned to make a sliding fit within a corresponding portion of the socket, and entry of the circularly-cylindrical portion into such corresponding socket portion is inhibited by engagement of the one part with the other if the socket is depressed in a tilted disposition. 00 30

14. An appliance as claimed in any one of claims 11 or 12 or 13 wherein a circularly-cylindrical post is provided within the circularly-cylindrical socket member, the post extending coaxially of the circularly-cylindrical socket member, and the shutter is annular and is arranged 35 to be displaceable within the annular space between the internal surface of the circularly-cylindrical socket member and the external surface of the post.

H:\MCoope\Keep\speci\69038.98.doc 24/01/00 16 An appliance as claimed in any one of claims 11 to 14 wherein an electrical contact ring is provided in said circularly-cylindrical socket member and an electrical terminal is provide on the plug part for contacting said contact ring when the plug and socket parts are operably engaged.

16. An appliance as claimed in claim 15 wherein the electrical terminal provided on the plug part has a contact carried by a terminal spring near the surface of a member of the plug which is adapted to be inserted into the circularly-cylindrical socket member.

17. An appliance as claimed in claim 14, or as claimed in claim 15 or claim 16 as dependent upon claim 14, wherein an electrical contact ring is provided on said post and an electrical terminal is provided on the plug part for contacting said contact ring on said post when the plug and socket parts are operably engaged.

18. An appliance as claimed in claim 15 wherein the electrical terminal provided on the plug part for contacting the contact ring on the post has a contact carried by a terminal spring near the inner surface of a 25 hollow member of the plug which is adapted to be inserted into the annular space between the circularly-cylindrical socket member and the post.

19. An appliance as claimed in any one of claims S 30 to 18 wherein the circularly-cylindrical socket member and/or the post respectively is provided with a portion adjacent to the location of its respective contact ring which is dimensioned so that the respective terminal provided on the plug part does not drag across such portion 35 during insertion and removal of the plug part into and from the socket part.

H:\MCooper\Keep\Speci\6 9 J 8 .98.doc 24/01/00 17 An appliance as claimed in any one of claims to 19 wherein the or each said contact ring is formed of copper or of a copper alloy having a thermal conductivity approaching that of copper and has a thick plating layer of silver antimony alloy.

21. An appliance as claimed in claim 14, or as claimed in any one of claims 15 to 20 as dependent upon claim 14, wherein said post is hollow.

22. An appliance as claimed in claim 21 wherein an electrical contact is provided within said hollow post and a terminal pin is provided on the plug part for entering into the hollow post and contacting said electrical contact when the plug and socket parts are operably engaged.

23. An appliance as claimed in any one of claims 1 to 8 wherein said connector system has interconnecting male and female parts, said female connector part having a plurality of movable shutter elements having surfaces which together define a concavity for receiving the male connector part, and a releasable locking member holding said plurality of shutter elements in closed condition until released, the arrangement being such that the 25 insertion of the male connector part into said cavity serves to release said locking member and to urge said o• oo*..shutter elements open for enabling electrical terminals of said male connector part to engage conductors provided in the female connector part.

24. An appliance as claimed in claim 23 wherein said oo concavity is circular in plane view and has a generally conical or frusto-conical form, the arrangement being such as to enable the male connector part to mate with the o• 35 female connector part throughout a 3600 range of related rotation of the male connector part with respect to the female connector part.

H:\MCoper\Koep\Sci\69038.98.doc 24/01/00 18 An appliance as claimed in claim 24 having two shutter elements each of which has a surface portion defining one half of a circular, frusto-conical concavity, and the two shutter elements are pivotally mounted so that in the closed condition of the shutter elements the said surface portions face each other.

26. An appliance as claimed in claim 24 wherein the underside of each of said shutter elements is provided with a formation which, when the shutter elements are in closed condition, together co-operate with said locking member, and the locking member is displaceable by the male connector part on insertion of the same into the concavity of the female connector part so as to free said formations from the locking member and thereby enable the shutter elements to open.

27. An appliance as claimed in claim 26 wherein the locking member is located at the apex of the frusto-conical cavity so as to be displaceable by an appropriately formed portion of the male connector part.

28. An appliance as claimed in claim 27 wherein the locking member has an electrical conductor of the female 9. 25 connector part, said electrical conductor being adapted to be contacted by a central terminal of the male connector part. 9 9

29. An appliance as claimed in any one of the 30 preceding claims wherein the connector that is provided on the base includes water-shedding formations. *9.

30. An appliance as claimed in claim 29 wherein an annular rim of the connector that is provided on the base 35 is formed with castellations, the inner surfaces of the upstands whereof form part of a female conical annulus serving to guide the vessel connector into the base H:\MCooper\Keep\Speci\69038.98.doc 24/01/00 19 connector, and the surfaces between the upstands whereof form part of a male conical annulus for encouraging the shedding of water between the castellations.

31. An appliance as claimed in any one of the preceding claims wherein the connector on the vessel is formed as an integral part of said overtemperature disconnect.

32. An appliance as claimed in claim 31 wherein the overtemperature disconnect device is provided above the connector of the vessel and underlying the vessel heating element.

33. An appliance as claimed in any one of claims 1 to 32 wherein said concentric electrical parts include, on one of the two connectors, first and second annular terminals spaced concentrically with respect to each other and a third terminal within the innermost one of the first and second terminals, the other of the two connectors having complementary terminal parts adapted to engage the terminal parts of the first mentioned connector.

34. An appliance as claimed in any one of the 25 preceding claims wherein the electrical connectors that are provided on the base and on the vessel are generally centrally positioned under the vessel and on the upper side of the base. S H:\MCooper\Keep\Speci\69038.98.doc 24/01/00 20 An appliance as claimed in claim 1 and substantially as herein described with reference to the accompanying drawings. Dated this 27th day of January 2000 OTTER CONTROLS LIMITED By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia Cg\MCooper'\Keep\Speci\69038.9B.doc 27/01/00