FR2633816A1 - Individual table plate heater - Google Patents

Abstract

The invention relates to individual heating discs which can be placed under each plate of a dining table for keeping them at a constant temperature throughout the duration of meals. The device comprises heating discs of small thickness, of approximately 15 cm in diameter, which are fitted with an electrical heating element 4 connected to a two-wire 24-volt power supply by virtue of cold flexible and flat connecting leads 2. The heating discs may be grouped together in variable quantities in order to match the number and the layout of the plates, regardless of the shape of the table.

Description

INDIVIDUAL TABLE PLATE HEATER
The invention relates to a device which makes it possible to maintain the plates placed on a table at constant temperature during their use by the guests.

It is usual to find that the dishes contained in the plates arranged on a table of guests get cold during meals and that often, mainly in the cold season, it becomes unpleasant to eat cold food with frozen sauces.

The system which consists in heating the plates, outside the table, before their use, brings only a partial solution to the problem because it is effective only if the duration of the meal does not exceed a certain limit which varies according to the calorific capacity of the plate, the nature and the importance of the dishes present.

In addition, it involves prior planning and handling, transport of items that can be very hot, changes of plates for each dish; Finally, it is a solution that is difficult to apply in the home.

The hot plate in the center of the table does not solve the problem of cooling the plates of the guests either.

The device which is the subject of the invention makes it possible to remedy this situation by allowing each plate to be kept at the right temperature throughout the meal, whatever the duration thereof.

The device according to the invention shown in FIG. 1 is constituted by heating discs (1) of small thickness, of approximately 15 cm in diameter, provided with a flat non-heating connection tail (2) of approximately 12 cm. length. This has a bipolar connector in the form of a small plastic parallelepiped (3) from which emerge, on either side of its axis, two metal pins (5).

The heat input provided by the disc is provided by an electric heating resistor (4) fixed on the disc, each end of which is welded respectively to one of the two pins (5) of the connector (3).

When the heating resistor (4) is supplied with a low voltage electric current via the connector (3) described above, the disc is the seat of sufficient heat to maintain a constant temperature of about 40-C a plate (6) placed on its upper face.

By way of example, these heating discs can be placed on a table (7), as shown in FIGS. 2 and 3, between the protective fleece fabric (8) in direct contact with the table and the upper presentation tablecloth ( 9). The flexibility of the connection shanks is such that their ends are positioned vertically along the drop of the table.

All the plate heaters are connected together according to the diagram in FIG. 4 by means of two-wire connecting straps (10) provided at each end with the same female connector (11) capable of coupling to one or the other. other pair of free pins of the connector (3).

A special connector (12) convects between the two-wire supply loop (13) of the heating discs and the safety transformer (14) placed on the ground and supplied from the 220 V public network by a power outlet (15 ).

The transformer (14) lowers the input voltage from 220 volts to 24 volts to guarantee personal safety.

It will be noted that each heating disc (1) is supplied with 24 volts in two-wire bypass on the loop (13).

Their number can therefore be variable as long as the total cumulative power they represent does not exceed the total power available at the secondary of the step-down transformer (14).

In an alternative embodiment shown in Figure 6, the heating resistor (4), placed inside a sealed and insulating plastic pipe, is immobilized between two cotton fabrics (17). The inner face of the lower fabric is treated with aluminum powder to form a layer (18) with a high coefficient of thermal reflection. The assembly constitutes a disc approximately 4 mm thick with thinned edges. The cold and flat connection tails (2) consist of two flexible conductive copper wires (20), kept equidistant thanks to a plastic coating (19), having the shape shown in FIG. 7. The flat cable thus formed has a thickness less than 2mm for a width of about 10mm; at one end, the two conductors are connected to the heating resistor (4) and at the other end to the two pins (5). The plastic coating (3) isolates the two pins and keeps their spacing constant and equal to the interval between the pins (5).

The circular shape of the heating device is not limiting. For example, a square shape may be perfectly suitable to simplify the cutting of the fabrics protecting the heating resistance.

For family use, the isolation transformer has an available power of 80 to 120 VA with an output voltage of 24 Volts. This can be fixed or adjustable with an electronic variator to allow rapid heating associated with a more moderate holding temperature.

For industrial applications, with a large number of heating discs, the individual transformer can be replaced by a distribution network under 24 Volts with sockets for each set of heating discs.

Claims (7)

1 / Individual device allowing to maintain at constant temperature plates placed on a table during their use by the guests. The invention is characterized in that it comprises in combination heating discs (1) of small thickness, of approximately 15 cm in diameter, with an incorporated electrical resistance (4) which can be inserted into a low-voltage two-wire network by means of a bipolar end connector fitted with through pins (5). Each heating disc is placed under the plate of each guest between the protective fleece of the table and the presentation tablecloth. A variable quantity of discs can be placed on a table; the assembly thus formed is supplied with low voltage of 24 Volts thanks to an isolation transformer supplying at the output of its secondary winding a voltage of 24 Volts. 2 / Device according to claim 1 characterized in that the heating disc (1) is supplied under the full voltage provided by the transformer thanks to its bipolar connector, characteristic which allows the user to install a variable number of discs while keeping each of them its nominal thermal power per unit. 3 i Device according to claims 1 and 2 characterized in that the bipolar connector of each disc in the form of an inverted T offers a double connection with the two-wire supply so as to ensure its own derivation of electrical energy and the supply of the disc following. 4 / Device according to claims 1, 2 and 3 characterized in that the low voltage power cable from the transformer ends in a T-shaped distribution connector (12) so as to be able to supply each side of the table by dividing, in this place, the common feeding trunk (16), in two branches which can develop in two opposite directions. 5 i Device according to claims 1 and 3 characterized in that the connections between the heating discs consist simply of a pair of wires provided at each end with the same bipolar female type connector to be inserted on the pins (5) of two discs adjacent heaters. 6 / Device according to claims 1 and 2 characterized in that the connection tail (2) of the heating disc consists of a flat two-wire cable, flexible and non-heating, coated with a plastic veil (19) providing insulation and the equidistance of the two connecting wires (20) with a total thickness of approximately 2 mm. 7 i Device according to claims 1, 2, 3 and 5 characterized in that the heating disc (1) provides a very localized heat source substantially of the same dimension as a base plate, which can be placed discreetly under each plate, whatever their number and their location to constitute a set of heating places adapted exactly to the variable layout of the plates set up by the user.