Multi-purpose tile heater

Abstract: The invention relates to heating tiles (30) including heating means (12) incorporated therein, the heating means (12) being connectable to heating means (12) of adjacent tiles. More particularly, the invention provides heating tiles (30) which have electrical resistance wires (12) on their under surfaces which are covered with a non -conducting sheet (16), adjacent tiles (30) being physically and electrically connected to provide any chosen area for heating such as the bottom of a bird cage, kennel or for heating blankets.

Description: This invention relates to a heating tile. It is an object of the present invention to provide a tile having heating means which may be joined to the heating means of other tiles with transfer of the heating means between tiles so that a heater surface of desired area may be provided. The invention is particularly suited for animal cages, kennels and the like enclosures but it will be appreciated that it may be used for human housing, offices and many other applications such as bed heaters, bathroom surfaces, heating of pipes and the like. Heating tiles are known from GB-A-1034723 and DE-C-3609782. Such tiles are provided with means for electrical interconnection of adjacent tiles, but have no additional means for mechanically linking the tiles together. The present invention provides heating tiles including a heating element comprising an electrical resistance circuit connectable to a source of electricity and incorporated into each tile; characterised in that the tiles include respectively tongue and groove formations and electrical contact pads on the tongue and groove formations to effect mechanical and electrical interconnection. Particular embodiments of the invention are as set forth in the dependent claims. The heating elements may be embedded, printed, or otherwise incorporated into the tiles. The heating elements may be silk-screened on to the tiles. The tiles may be of any suitable size having regard to the Application. According to the invention the tiles include interengaging tongue and groove formations for a physical connection as well as the electrical connection. In a preferred form of the invention each tile has resistance wires on their lower surfaces and these are connectable to the resistance wires of the adjacent tiles when the tiles are joined together. The tongue and groove physical connection elements may include electrical connections. In one form of the invention the lower surfaces having the resistance wires are covered with a sheet of electrically non-conductive material or other tile without resistance wires. Tiles of the order of 10cm square are useful for bird cages or dog baskets or as electric blanks for humans. The uses of an assembly of the tiles of the invention are extensive. EMBODIMENT OF THE INVENTION An embodiment of the invention is described with reference to the accompanying drawings: Figure 1 is an isometric view of the tile according to the invention; Figures 2 and 3 are enlarged sectional views of the tile; Figure 4 is a similar view showing the peripheral connection elements in part engagement with the tiles; Figure 5 is an end view of a corner connection element; Figure 6 is an isometric view of an assembly of tiles into a box formation; and Figure 7 is a sectional end view of a pipe with curved tiles. In the drawings tiles 30 are provided in the form of a square and are constructed from two halves 10 and 16. Resistance wires or electrical elements 12 are either attached or embedded into the lower surface of the upper half 10, and extend to contact pads 17 which are located on one interengaging connection formation 18 as illustrated in Figure 1. The two halves 10 and 16 are then either glued, or welded by ultrasonic means or solvents so as to seal the electrical element from moisture ingress. Reference to Figure 3 shows how the interengaging connection formations slot into each other allowing the copper contact pads 17 to connect the circuits between tiles. In Figure 4 the sectional view shows how the elements may be connected to a supply of low voltage current. Conduits 20 are provided which also have matching interengaging formations to the tiles and likewise also include contact pads 17, so that a very neat and convenient method of constituting a large heating surface may be provided. The conduits in this drawing are shown in part engagement and it will be readily appreciated that when completely engaged they will create a very firm and compact border to the heating pad. The joints between the tiles may, if required, be sealed by any suitable compound. In Figure 5 the corner connector and conduit 22 is shown which allows an enclosed space to be heated. This feature of the invention is shown in Figure 6 where a box is assembled using a number of tiles together with corner connections. This facility will provide ideal incubation chambers for laboratories where a great demand exists for controlled temperature cabinets. Referring to Figure 7 a pipe 32 is shown covered by curved heating tiles 34. This application will facilitate the flow of viscous liquids along pipe lines in food processing or other industrial uses. The assembly of tiles is connected to a source of electricity depending on what source is available and, if necessary the source may be transformed. A variable resistance or equivalent may be provided to adjust the temperature of the tiles. The tiles of the invention may be flexible or deformable for greater versatility - for example for cladding pipes and other non-planar shapes.

Claims: Heating tiles (30) including a heating element (12) comprising an electrical resistance circuit connectable to a source of electricity and incorporated into each tile; characterised in that the tiles include respectively tongue and groove formations (18) and electrical contact pads (17) on the tongue and groove formations to effect mechanical and electrical interconnection. Heating tiles according to Claim 1, further characterised in that each tile is formed of two superimposed halves (10, 16); in that the electrical circuit (12) is located on the undersurface of the upper tile half (10) and is covered on the undersurface thereof with a non-conducting layer (16); and in that the groove formations are formed between the upper tile half (10) and the non-conducting layer (16). Heating tiles according to Claim 2, characterised in that the electrical resistance circuit (12) is applied to the undersurface of the upper tile half by silkscreening.

Inventors: DU PREEZ JOHANNES JACOBUS, DU PREEZ, JOHANNES JACOBUS
Applicants: DENEL PTY LTD, DENEL (PTY) LIMITED
Application year: 1992
Main classification: F24D13
IPC codes: F24D13