ELECTRICAL APPLIANCES

Abstract: An electrical appliance system comprises a common "cordless" base unit (4) and a number of electrical appliances (2), particular domestic kitchen appliances, which can be interchangeably placed in the base to supply power thereto.

Description: Electrical Appliances The present invention relates to electrical appliances, and in particular to small domestic electrical appliances as might be used, for example, in a kitchen. At the present time, a large number of different domestic appliances are available on the market for performing a number of different tasks. Examples include electric coffee grinders, coffee percolators, can openers, juicers and the like. Normally each appliance is a stand alone unit provided with a fixed power lead, which must be unfurled and plugged in every time it is desired to use the appliance and then unplugged and the power lead furled away again after use. This is both inconvenient and time consuming, which means that in practice, the user may not bother to use the appliance at all. According to the present invention, there is provided an electrical appliance system comprising a base unit having an electrical connector provided in or on an upper surface thereof, and a range of electrical appliances, each of which is locatable on said base unit and has an electrical connector adapted to engage with the electrical connector on said base unit when the appliance is located thereon. Thus in accordance with the invention, a base unit is provided which can accept a range of (ie. two or more) appliances thereon, so as to provide a "cordless" connection for each appliance. This will be considerably more easy and convenient to use than existing appliances. Preferably the base connector stands proud of the upper surface of the base unit, so as considerably to facilitate positioning of the appliance on the base. Preferably the respective electrical connectors in the base unit and appliance are of the type which can be engaged with one another irrespective of their relative rotational orientation. This is particularly advantageous in that it will allow the various appliances to be easily located on the base unit without having to worry about their rotational alignment. Connectors of this type are disclosed, for example, in WO 95/08204 and in WO 94/06185, the former relating to our own commercially available P72 connector. The respective connectors are thus preferably discrete, interengaging connector units or assemblies suitably mounted in desired positions on the respective appliance and base, most preferably inwardly of the respective peripheries thereof. Preferably the respective connectors are arranged generally centrally of the appliance receiving portion of the top of the base unit and centrally under the bottom of the appliance. In a preferred embodiment, the base unit may be provided with electrical switch means arranged in the electrical supply to the base connector to allow appliances placed thereon to be switched on and off by a user. This is advantageous since it allows a single switch to be provided for a range of appliances, rather than having a switch provided on each appliance, which results in clear cost savings. The switch may be a simple manually operable on-off switch, or may be a timer switch. Such a timer switch could be arranged, for example, to switch on and/or off at desired times, or to be switched on for a desired length of time, and could be mechanically or electronically controlled. The provision of a manually operable on/off and/or timer switch in the base unit of or for a cordless appliance is itself believed to be a novel arrangement. From a further aspect therefore, the invention provides a base unit for an electrical appliance, said base unit having an electrical connector adapted to engage with an electrical connector on said appliance, and further comprising a switch for selectively controlling the supply of electrical energy to the electrical connector of the base unit. Alternatively, of course, the electrical supply to the appliance may be connected and disconnected simply by placing the appliance on or removing it from the base. This may be appropriate for appliances which will be energised for only a short time, for example coffee grinders. Of course, if this arrangement is used, the respective electrical connectors in the appliance and base should be constructed to withstand the repeated making and breaking of electrical contacts. Accordingly the connectors may be provided with appropriate contacts, for example silver contacts or silver plated contact portions. For example, in the preferred arrangement, using an electrical connector of the type described in WO 95/08204 in which the electrical connector in the appliance comprises a central line pin surrounded by a neutral ring, the end of the pin may be provided with a silver contact or be silver plated and the lower end of the neutral ring silver plated. The corresponding neutral leaf spring in the base connector at least may be provided with a contact . In order to indicate that an appliance placed on the base is energised, an indicator such as a neon may be provided on the base unit. The base unit may have means for securing it to a work surface. In one embodiment, for example, the base unit could be provided with one or more suction pads. The electrical connector in the base unit may be connected to a power lead having a plug at its other end for plugging into a wall socket, for example, to provide power to the base unit. Alternatively, the base unit may be adapted to releasably engage with a power outlet of another appliance, such as an electric cooker. In one embodiment, for example, the base unit may be adapted to engage in the well of an electric cooker having removable elements, and have means for connecting electrically with the element power supply. Such an arrangement is described in our US Patent 5415572. Alternatively, the electrical connector of the base could be built directly in to a work surface, so that the various appliances may be positioned directly on the work surface to make electrical connection with a power supply thereto. In this case the work surface would effectively provide the base. From a yet further aspect therefore, the invention provides a domestic electrical appliance installation comprising a work surface or the like having an electrical connector provided therein or thereon so as to engage with an electrical connector provided in an electrical appliance when the appliance is placed thereon. The invention is particularly suited to static domestic kitchen appliances. Typically such appliances would have heating means or motor means . Appliances to which the invention could be applied include, for example, kettles, coffee percolators, juicers, coffee grinders, knife sharpeners, can openers, popcorn makers, egg boilers, food blenders, and so on. It is not common practice to provide such a range of domestic appliances with "cordless" connectors and from a further aspect, the invention also extends to domestic electrical appliances having electrical connectors arranged and adapted for engagement with a base unit, in accordance with the invention. In use, the user could leave one main appliance, which is the one most commonly used, in position on the base unit for most of the time, remove it when it is needed to use another appliance, position the other appliance on the base unit for use, and after use replace it with the main appliance again. The base unit and one or more appliances could be purchased together as a set. For example a coffee making set could comprise a base unit together with a coffee grinder and a coffee percolator. When it is desired to make coffee, fresh beans could be placed in the grinder which is then placed on the base unit and energised to produce ground coffee. This can then be transferred to the percolator which can then be placed on the base unit and energised to produce a coffee beverage. Alternatively, a base unit and one appliance could initially be purchased together, and further appliances then purchased separately, as additional units, as and when required. Some preferred embodiments of the invention will now be described with reference to the accompanying drawings in which: Fig. 1 shows a small electrical jug kettle arranged for engagement with a base unit; Fig. 2 shows the kettle of Fig. 1 engaged on the base unit; Fig. 3 shows schematically an electrical juicer engaged on a base unit; Fig. 4 shows schematically a coffee grinder engaged on a base unit; Fig. 5 shows schematically the electrical connectors used in the arrangements of Figs. 1 to 4; Fig. 6 shows schematically, a plan view of a different base unit suitable for use in the invention; and Fig. 7 shows a side view of the base unit of Fig. 6. With reference to Figs. 1, 2 and 5, a small jug kettle 2 of say two to three cups capacity is arranged over a base unit 4. The base unit 4 is circular in plan has a circular section socket connector 6 mounted on its upper surface 8. As shown schematically in Fig. 5, the connector 6 is provided with a central, live, spring contact 10, a neutral spring contact 12 and an earth spring contact 14. The live contact is accessed through a central hole in the upper surface 16 of the connector 6, the neutral contact 12 through an annular slot in the upper surface 16, while the earth contact 14 extends through a side wall 18 of the connector 6. The respective contacts terminate in terminals which are connected to the wires of an electrical lead 20 which is connected to a plug (not shown) for insertion into a wall socket, for example. The base connector 6 is thus a discrete component which is mounted in the upper surface of base unit in the desired position. The kettle 2 has a discrete plug connector 22 fixedly mounted generally centrally under its base. The pin connector has a central live terminal pin 24 for engagement with the live contact 10 in the base, an annular neutral pin terminal 26 for engagement with the neutral base contact 12 and an annular earth contact 28 extending around an inner wall of the connector 22 for engagement with the base earth contact 14. As shown schematically in Figs. 1 and 2 the live and neutral terminals are connected to wires 30,32 which are electrically connected to a heating element (not shown) of the kettle through a conventional control unit (not shown) . Further details of the respective electrical connectors described above can be obtained from our aforementioned international patent application, WO 95/08204 the content of which is incorporated herein by reference. When the kettle 2 is placed on the base unit 4, the power is supplied to the element by the user operating an on/off switch 34. When it is desired to use another appliance, the kettle 2 may be removed and another appliance, such as an electric juicer 40 (Fig. 3) or coffee grinder 42 (Fig. 4) may be positioned on the base unit 4 for operation. In both the embodiments of Figs. 3 and 4, the respective appliances are fitted with the same design of pin connector 22 centrally of their bases, as in the earlier embodiment. The terminals of the connectors are connected to the respective drive motors of the appliances by suitable wiring, and switch means may be provided in the appliances, if desired. Alternatively, a switch may be provided in the base unit. This avoids the need for switches to be provided in the individual appliances. A base unit 50 incorporating a switch unit is shown schematically in Figs. 6 and 7. In this embodiment, a switch (not shown) , is connected in the electrical supply between the power lead 52 and the base connector 54 which is provided centrally of an appliance receiving portion 56 of the upper surface of the base. The switch has manually operable 'on' and 'off buttons 60,62. It also has setting buttons 64,66,68 which can be used to set a desired time of operation of the appliance, to pre-set a start time for operation, and so on. The time, operation time etc. may be displayed on a clock 70 on the base. For example, the desired operating time may be set using buttons 64 and 66 and the time started using button 68. The time may be reset, cleared or operation paused by further pressing buttons 64,66,68 respectively. The timer function may be overridden by the main buttons 60,62. Of course the timer arrangement disclosed is purely exemplary, and other arrangements will readily occur to the skilled person. It will be appreciated that many changes may be made to the particular embodiments described above without departing from the scope of the invention. For example the invention is not limited to the particular form of electrical connector described, although this is preferred. Whilst the appliance connector is shown as a discrete separate component, it may of course be incorporated as part of a larger assembly, for example forming part of an integrated control unit for the appliance. By providing a range of electrical appliances each with its own built-in electrical connector and a common base unit having a compatible electrical connector, the invention allows a user to benefit from the advantages and convenience of using a "cordless" appliance, but at significant savings of both cost and storage space.

Claims: Claims 1. An electrical appliance system comprising a base unit having an electrical connector provided in or on an upper surface thereof, and a range of electrical appliances, each of which is locatable on said base unit and has an electrical connector adapted to engage with the electrical connector on said base unit when the appliance is located thereon. 2. A system as claimed in claim 1 wherein the respective electrical connectors in the base unit and appliance are of the type which can be engaged with one another irrespective of their relative rotational orientation. 3. A system as claimed in claim 1 or 2 wherein the respective connectors are arranged generally centrally on the top of the base unit and centrally under the bottom of the appliance. 4. A system as claimed in any preceding claim wherein electrical switch means is provided in the base unit. 5. A system as claimed in claim 4 wherein said switch means is manually operable. 6. A system as claimed in claim 4 or 5 wherein said switch means is a timer switch. 7. A system as claimed in any preceding claim wherein the base unit has means for securing it to a work surface. 8. A system as claimed in claim 7 wherein the base unit is provided with one or more suction pads. 9. A system as claimed in any preceding claim wherein the base unit is adapted to releasably engage with a power outlet of another appliance. 10. A system as claimed in any preceding claim wherein an indicator is provided in said base unit . 11. A system as claimed in any preceding claim wherein said appliances are domestic kitchen appliances. 12. A domestic electrical appliance installation comprising a work surface or the like having an electrical connector provided therein or thereon so as to engage with an electrical connector provided in an electrical appliance when the appliance is placed thereon. 13. A base unit for an electrical appliance, said base unit having an electrical connector adapted to engage with an electrical connector on said appliance, and further comprising a switch for selectively controlling the supply of electrical energy to the electrical connector of the base unit.

Inventors: BRODIE JOHN MCCORMICK, ROBERTS JASON MARK, TAYLOR JOHN CRAWSHAW, BRODIE, JOHN, MCCORMICK, ROBERTS, JASON, MARK, TAYLOR, JOHN, CRAWSHAW
Applicants: BRODIE JOHN MCCORMICK, ROBERTS JASON MARK, STRIX LTD, TAYLOR JOHN C, BRODIE, JOHN, MCCORMICK, ROBERTS, JASON, MARK, STRIX LIMITED, TAYLOR, JOHN, CRAWSHAW
Application year: 1996
Main classification: A47J27
IPC codes: A47J27, H01R13, H01R24