DE20306052U1 - Electrical kettle with power supplied by placing on a base having contacts to a ring conductor - Google Patents

Abstract

The item of equipment e.g. an electrical kettle [1] is supplied with power when it is placed on a base [5] The base has pressure activated switches [51] coupled to the supply. These are operated by engagement with a ring [60]. Power to the heating element is fed through conductor rings [62,63] engaged by contacts [53].

Description

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Electrical socket of a conductive base

BACKGROUND OF THE INVENTION 1) Field of the invention

The present invention relates to an improved embodiment of an electrical socket of a conductive base, in particular with a base of a known heating pot with an electrical power supply. Thanks to this improvement, the power supply can be interrupted with a pressure switch when lifting

&iacgr;&ogr;, which is a safety measure to prevent electric shock.
2) Description of the known embodiment

The previous method of supplying electricity to electric and heated pots was to supply the electric current directly to the electric heating element of the pot through an electric cable and a control switch or just an electric cable with a plug in the socket. Provision has recently been made to supply all the electrical connections to a base on which the pot is placed. The electric heating element of the pot is supplied with electricity through the socket of the pot, and this supply is interrupted when the pot is lifted. It is more convenient and safer when the pot is lifted if no cable is attached to it. The base is continuously supplied with electricity and is provided with a connector in a position corresponding to the socket of the pot. When the pot is put back down, the connector is

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on the base is conveniently inserted into the socket of the jug to ensure the connection to the power supply. However, the connector can easily cause a short circuit if accidentally touched by a finger or drops of water.
A newer design is aimed at reducing these risks of electric shock by inserting a conductor ring into a circular socket groove, while the conductor surfaces are provided vertically on the ring shape and along the wall of this socket groove to avoid accidental contact. However, the circular ring is

&iacgr;&ogr; is constantly charged with current and can easily cause a short circuit if water drops or foreign objects get into the groove. Fig. 1 and Fig. 2 represent this conductor ring/groove, wherein an electric and heatable jug (1) and a base (13) of this jug are inserted into a socket (3), while the periphery of the base (13) is provided with an annular edge (131) with which the base is ring-shaped. A jug handle (11) is equipped with a power switch (12), while the base (2) is provided with a connector (4) corresponding to the position of the socket (3) of the jug (1) on the underside thereof. The connector (4) is connected directly to the power source (23) and is constantly supplied with current. The base (2) has a positioning ring (21) which corresponds to the ring edge (131) of the jug (1) for correct positioning, while a circular ring (22) enables a precise seating height of the jug (1) for the correct placement or for the connection between the socket (3) and the connector (4) in order to ensure the electrical and

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to supply the heated jug (1) with electricity. The socket (3) of the heated jug (1) ensures the power supply via the power switch (12) for the control, after which the power is fed to the internal heating element (10) of the jug (10).

Fig. 1 shows that the connector (4) of the base (2) protrudes upwards. Fig. 2 further shows the circular circuit boards inside the connector (4) with a central electrode plate (41), peripheral electrode plates (42) and (43) forming a circular groove (40) and an insertion hole (410) in the middle. In this

The conductor plug (31), the conductor rings (32) and (33) of the socket (3) of the jug are inserted into the insertion hole (410) in order to enable multiple circuit connections.

However, the constant-charge electrodes of the connector (4) are exposed; non-insulating foreign bodies between the electrode plates (42), (43) or in the circular ring (40) or in the insertion hole (410) may cause a short circuit. In order to allow the jug (1) to be easily lowered, the connector (4) of the base (2) must project upwards and be parallel to the surface of the table and is thus particularly exposed to the risk of a short circuit caused by foreign bodies or water drops when the jug is not disconnected from the power source (23). Therefore, this conventional embodiment requires improvement by providing a safety measure so that the constant-charge circuit is disconnected from the power source when the jug (1) is lifted from the base (2), thus reducing the risk of an electric shock.

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to avoid shock.
SUMMARY OF THE INVENTION

The present invention therefore consists in providing an improved embodiment of a conductive base on a seat, whereby a pressure switch only presses on a pressure ring when the jug is placed on it and then all the conductor terminals are supplied with power. When the jug is lifted up, the pressure switch is also released, interrupting the power supply, thus also reducing the risk of a short circuit.

&iacgr;&ogr; avoid.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the object of the present invention, its structure, innovative features and achievements, the following brief description of the drawings by which this present invention is illustrated is followed by a detailed description of the preferred embodiment.

Fig. 1 shows a schematic exploded view of the jug base, the socket, the seat and the plug of the seat of an electric heating jug according to the known embodiment.

Fig. 2 shows a sectional view of the socket of the jug and the plug of the seat of an electric heating jug according to the known embodiment.

Fig. 3 shows a perspective view of the structure of the underside of the seat according to the present invention.

Fig. 4 shows an exploded and a sectional view of the

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base, ring circuit board, positioning blocks, pressure cylinder, seat with positioning notch and contact terminals of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED

EXECUTION

As shown in Fig. 3, which is a bottom view of a seat (5) of the base of the present invention, in which a power supply cable (23) is first connected to an incoming contact terminal (512) and to an outgoing contact terminal (513)

β connected to a pressure switch (51). The outgoing power cable supplies several upstream conductor terminals (53), while a middle terminal (530) serves as a common grounding device (see Fig. 4). The conductor terminals (53) are arranged according to their different radius or radial orientation to

is to correspond to different positions of the ring conductor plates (61), (62), (63) on the bottom of a pot (1) depending on the different circuit loops. By selecting different circuit loops according to the correspondingly selected conductor terminals, the number of heating elements on the circuit is changed in order to control the heating power. The heating element is constructed of at least two or more PTC (positive temperature coefficient of ceramic resistance parts) heating units.

The ring conductor plates (61), (62), (63) of the electric can (1) are arranged on the conductor discs (6), which in turn correspond to the radius of the seat (5) in order to ensure a precise fit, which

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for precise positioning of peripheral ring blocks (50) from the outside. The special safety device of the present invention consists of a pressure switch (51) in which a sliding block (511) is elastically pushed to an upper position. When a pressure ring (60) of the electric can (1) is pushed downwards through a narrow slot (52) of the seat (5), thereby pushing the sliding block (511), the pressure switch (51) is moved to the position to supply current to all the conductor terminals (53). In other words, the conductor terminals (53) can only be supplied with current

&iacgr;&ogr; can be charged when the pressure switch (51) is pressed. When the electric jug (1) is lifted up, the conductor terminals (53) are immediately disconnected from the power supply.

The present invention also further secures the seat (5) with a plurality of positioning notches (54) on the peripheral ring block (50), the positioning blocks (14) being received on the bottom of the electric can (1) for locking to prevent slipping on the edge of the circuit boards (61), (62), (63) and thus possible wear, instability or interruption of the electric current.

The pressure switch (51) is pressed down with the sliding block (511) while the sliding block (511) is pressed with the pressure ring (60) of the electric jug (1). The pressure ring (60) with a wall thickness of 2 mm to 3 mm or less fits through the narrow slot (52) to press the pressure switch (51) to turn on the power. The narrow slot (52) is too narrow for a

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accidental insertion of the finger and usually the push button (51) cannot be pressed by hand unless it is pressed with a tool. This is a safety feature.
The pressure switch (60) of the electric jug (1) is circular in shape to reinforce the structure of this electric jug (1). This also allows a very flexible fit between the seat (5) and the pressure ring (60), which facilitates the synchronized pressing of the pressure switch (51) to switch on the power supply.

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Claims (3)

1. The electrical socket of a conductive base with conductor terminals on the base of the electric jug ( 1 ) in the form of a pressure switch ( 51 ) installed between the power source and the conductor terminals ( 53 ) to interrupt the power supply when the electric jug ( 1 ) is lifted up; the pressure switch ( 51 ) is usually protected under a narrow slot ( 52 ) and can only be pressed with the pressure of the pressure ring ( 60 ) of the electric jug ( 1 ) which can be precisely fitted into this circular narrow slot ( 52 ). 2. The electrical socket of a conductive base according to claim 1, characterized in that the peripheral ring blocks ( 50 ) of the seat ( 5 ) serve to receive and protect the electric jug ( 1 ), while the positioning notches ( 54 ) of the peripheral ring blocks ( 50 ) are designed to receive the positioning blocks ( 14 ) on the base of the jug for a good holding of the latter. 3. The electrical socket of a conductive base according to claim 1, characterized in that the pressure ring ( 60 ) under the electrical can ( 1 ) is designed in a circular shape for a more versatile fitting.