CA2182954A1

CA2182954A1 - System for generating heat by electric current through conducting bodies of micrometric thickness but large in area

Info

Publication number: CA2182954A1
Application number: CA002182954A
Authority: CA
Inventors: Aldo Stabile
Original assignee: Individual
Current assignee: ADARA ENGINEERING
Priority date: 1994-02-15
Filing date: 1994-03-30
Publication date: 1995-08-17
Also published as: EP0745312A1; AU6688594A; IT1273308B; ITMI940268A0; RU2126605C1; WO1995022236A1; ITMI940268A1; JPH09512944A

Abstract

System for generating heat by converting electric energy into thermal energy by passing electric current through conducting bodies (12, 16-18) of high conductivity, their thickness being measurable in microns and with a large ratio between width of the section and said thickness, said bodies being laid flat on their supports (11, 15) to create heat-emitting surfaces which not only heat but which diffuse as well.

Description

WO95/2223G 2 18 2 9 S 4 PCT~T9~/00039 SYSTEM FOR GENERATING HEAT BY ELECTRIC CURRENT THROUGH
CONDUCTING BODIES OF MICROMETRIC THIC~NESS BUT LARGE IN
AREA
Systems that use electricity for generating heat are in-numerable.
These systems are based on the use of materials of high resistivity which reach very high temperatures when elec-tric current is passed through them producing great concen-trations of heat.
Such temperatures are nearly always very much greater than those required by what has to be heated, whether this is a room, an oven, a hotplate or something else.
Heat must be diffused where the thermal head is so high and such diffusion requires means for the purpose which are both costly and complex. Wires carrying great heat need supporting materials of a special kind, such as cera-mics, difficult to produce and fragile when made, as well as complex structures for insulating and coating them.
High temperatures also mean hard wear on such structures while efficiency is low compared with direct energy pro-duced by fuel. Resistive materials are costly and this too increases purchasing and running costs.

Z182g.~ ~

The patented invention BE A 634 716 refers to heating elements made of a sheet of copper of a minimum thickness of mm 0.025 which presents a continuous spiral or intermittent cut supported by a rigid plastic lamina.
This patent BE A 634 716 discloses a copper sheet or band thickness 5 equivalent to or less than mm 0.020 with parallel cuts that alternately extend from one edge of the sheet or band to a short distance from the opposite edge, supported by a flexible insulating sheet or band of paper, cardboard, nylon, namely of materials that burn at low temperature.
Purpose of this invention is to lower production costs of the above 10 heating elements reducing the thickness of the conductors and using a flexible support that can be wound on a reel.
It is clear that this purpose can only be achieved if temperatures are very low and especially lower than those that would cause combustion of the material refered to above.
15 This invention therefore only concerns a very limited field of uses and where problems of running costs do not exist.
Purpose of ADARA invention for which a patent is now applied, is to lower cost of heating systems and equipment and also running costs of almost all types of such installations by means of a system that permits 20 generation of heat and its diffusion at the very moment when it is generated by electricity, and therefore a minimum thermal head and minimum dimensional difference between the size of the heating elements and the body or environment to be heated.
To obtain these results the material used for heating elements must be of 25 highly conducting nature such as copper. I
The thickness of these bodies is the minimum compatible with formation and mecchanical strength, great width and a length c~lc~ ted to produce, according to the intensity and voltage of the electricity used, a temperature slightly higher than that of the environment or the body to be 30 heated.
This system is valid both in therory and practice and it results show a really exceptional increase of efficiency and even in certain cases 2182~4 reducing running costs never before obtained with any other heating 5 system.
Experiments have been carried out by recognized Organizations.
In view of before going is clear that characteristics and effects of the ADARA system are not only superior to those of the BE A 634 716 but even make possible the use of electricity for heating; this applies also to 10 the cases where at present, for reasons of economy, there are no alternatives to heating by fuel or gas.

W09S/22236 218 2 9 ~ 4 PCT~T9~/OnO39 The above invention shows how electric energy can be trans-formed into heat by means of simple and practical structures, inexpensive to produce and to run, as will be fully explained below.
The invented system is based on the use of extremely thin conducting bodies, whose thickness is measured in microns, compatible with their formation and with the resistance nee-ded to withstand stresses during use, there being a high ratio between the width of the cross section and said fine thick-ness.Said conducting bodies are laid flat on their support, in lengths placed side by side but insulated one from another so as to obtain substantially continuous heat-emitting surfaces.
The material used to make the conducting bodies is a highly conductive one, such as copper or aluminium.
The length is established according to temperatures and to the desired concentration or diffusion of heat.
Strength of mains current can be intensified by transformers to increase the amount of heat generated.
Due to minimum thickness of the conductors and consequently large area covered by the source of heat, said source of heat also acts as a diffuser drastically reducing the thermal head compared with the temperature required to make the heat-ing equipment function efficiently.
As the case may require, conducting bodies can take the form of sheets, bands and the like, or be layers formed for elec-troplating or similar processes.
The conducting bodies are preferably placed serpentinewise or spirally on their means of support.

The serpentine can;be formed from a sheet in which parallel cuts are made alternatingly in one edge or in the edge oppo-site.

WO95/2223G 218 2 9 S 4 PCT~T9~/00039 The spiral may be circular, square, rectangular or of some other shape.
Along the lengths of conducting bodies the cross section may remain constant or may differ according to the amount of heat and to the temperature to be reached in tne various lengths. Variations in size may be gradual or sudden, con-tinuous or intermittent, as the particular case and prefer-ences may dictate.
The conducting bodies may receive electric current at their ends or at intermediate points.
Values of current that sup !y the ends or intermediate points may be equal or different.
Variations in values may be gradual or sudden, continuous or intermittent as the particular case.or preference may de-cide.This system can be used for a vas~ number of applications.
The heat-emitting surfaces can be placed around enclosed spa-ces in which temperatures higher than ambient temperatures are required for physical or chemical transformation of ma-terials, so creating static ovens.In tunnel, ring-shaped or similarly shaped equipment, in in-stallations generally where material to be baked or treated passes through slowly, such as in impregnating systems, said heat-emitting surfaces can create the most suitable thermal radiations achieving optimum disclocations and intensities.
The heat-emitting surfaces can be placed on internal walls, including the bottom surface, of baths, tanks and the like in which fluid materials are poured for physical or chemical transformations, such as electrolytic baths, or else placed on the flat parts of equipment and devices generally which must give off heat such as hotplates, or else inside vehicles in their side walls or on floors or roofs.

21829~4 W095122236 PCTnT9~/00039 Various alimentary items can be cooked or physically or chemically transformed by placing or creating said heat--emitting surfaces on the inside walls or on the base of different types of cooking or frying pans or of suitable receptacles in general.
By associating the heat-emitting surfaces to panels and the like, fixed or mobile radiators, stoves and the like can be created for heating indoor rooms.
The advantages of the invention are evident.
The system here described makes it possible to have gene-rators of heat, particularly useful in all those cases -which form the majority - where high concentrations of heat are unnecessary, such as in living and working rooms, in heating or cooking food, as well as in a great many indus-trial processes.Heat is produced almost instantaneously and the surfaces obtained by the system emit uniform heat.
The cost of the heating bodies is much lower than that of those at present in use.
The heat diffuser, today an essential item, is not needed as a single body is,at one and the same time, heater, emit-ter and diffuser.
The source of heat is easily created, whether it consists of sheets, bands or is to be used for electroplating.
The heating bodies are also in direct contact with the struc-ture to be heated, consequently evoiding a thermal chain.
If the equipment requires a transformer for stronger cur-rent, the lower voltage makes for greater operational safety.

Characteristics and purposes of the invention will be made still clearer by the following examples of its execution il-lustrated by diagrammatically drawn figures.

` W 0 95122236 218 2 9 S 4 PCT~T9~/OnO39 Fig. I Wall-mounted radiator.
Fig. 2 Static oven.
Fig. 3 Hotplate.
Fig. 4 Heated tunnel for impregnating work.
Fig. 5 Tank for an electrolytic bath.
Fig. 6 Heating system for motor vehicles.
Fig. 7 Heated tank.
Fig. 8 Domestic heating.
Fig. 9 Detail of the radiator in Fig. 8.
The radiator 10 comprises an insulating lamina 11 on which an extremely thin band, the thickness of which is measurable in microns, is laid flat, said band being of copper and be-ing arranged in the form of a serpentine 12 supported by a framework 15 for which any material may be used.
The end 16 of ~he serpentine is connected to a terminal 19 while the other end 17 is joined by a connecting sec.ion 18 to a second terminal 20 this in turn connected to the elec-tric main.
Said terminals are connected by the wire 2I to the plug 22.
The serpentine 12 is covered by a sheet of anodized alumin-ium 13.
Said radiator is mounted directly onto the wall 24 of the room 25, an apparatus clearly of the greatest simplicity.
Being so thin and yet so large in area the heat-emitter en-sures almost immediate and direct transfer of heat to theroom with no need for supporting materials of high thermal resistance such as ceramic for example; neither is there any need for diffusers.
Bulk and weight of the apparatus are practically negligible.

Neither are the framework and anodized aluminium cover real-ly necessary since the insularing and supporting lamina alone could be sufficient.

W095/22236 21 8 2 9 5 4 PCT~T9~/00039 Maximum temperature of the radiator can be maintained at a low level, only a little above ambient temperature.
This radiator ofers a high degree of efficiency and is easily adaptable to any room and to any kind of furnishing.

The parallelepiped static oven 30 contains heat-emitting surfaces inside its walls 31, said surfaces 32-34 consist-ing of a serpentine of copper band,similar to that previous-ly described, or equivalent means.
The generator 35 of electric current is connected by wires 36 and 37 to the terminals 38, 39.
On the stove top 40 is a hotplate 4I formed by the heat-emitter 42 consisting of a copper lamina of the kind already described.
Electricity from the mains reaches the hotplate 4I through the transformer 45 which increases intensity and upgrades heat.
From the transformer the wires 46, 47 connect to terminals 48,49. Uniform and direct heat is applied to the pan 43.

The impregnating system 50 comprises a tunnel 51.
The walls 52,53 of refractary material carry the heat-emi~ting surfaces 54,55 of copper laminae; these radia~e heat straight onto the two faces of the band 56 moving slowly between the reels 57, 58 drawn along by the pair of rollers 59.
Said heat-emitting surfaces 54, 55 are connected respectively by ~he pairs of wires 60,61 and 62, 63 to the current genera-tors 64, 65.
The bath 70 has walls 71 of refractary material, the inner ones being lined with a layer 72 of electrolytic copper.
The tank filled with liquid 75 contains the chmicals needed for operations carried out in the electrolytic bath.
Said layer of copper is connected by terminals 76, 77 and by wires 78, 79 to the electricity generator 80.

W095122236 2 18 2 ~ 5 ~ PCT~T9~/00039 In the motor vehicle 81, comfortable and uniform warmth is given out from the heat-emitting surfaces 82 consisting of fine copper bands arranged serpentinewise in the inner sides of the doors 83.
Said heat-emitting surfaces are connected to the generator 84 installed under the vehicle's bonnet 85 by the terminals 86, 87 and wires 88, 89.
The cylindrical tank 90 has walls 91 of refractary material, inside which is mounted the cylindrical heat-emitting sur-face 92 formed of a lamina whose lower ends are fitted withthe ter. nals 93.
The wires 94, 95 lead off from said terminals and are then connected to the transformer 96 for receiving main current.
By means of this transformer the heat level is increased, intensity of current being thereby raised.
In the room 100, below the windo~ 101, a radiator is fitted 102, a more detailed view of rich is shown in Fig. 9.
Mains electricity for the rad~ator is increased in intensity after passing through the transformer 103.
Through the terminals 104 and wires 105, 106, transformed current is sent to the two ends of the conducting aluminium cover 107 which clothes the two sides of the insulating plate 108.

Claims

1. System for generating heat to convert electric energy into thermal energy by passing electric current through lengths of constant section, of one or more thin electric conductors of high conducting material, such as copper, aliminium, characterized in that said conductors are of minimum thickness, measured in microns, compatible with the structural needs and mecchanical resistence to stresses in use, highest possible ratio compatible with the dimensions of the body or environment to be heated or with structural needs, between the width of the cross-section of the conductors and their thickness, a length such as can reach a temperature only slightly higher than that of the envirnment or the body to be heated, large surface area for maximum heat exchange surface with the body or environment to be heated, said area also corresponding to internal and external parts of the body to be heated and to one or all of the walls of the room to be heated, said conductors matching with a metal heat-emitting surface by means of an intermediate insulating layer, the purpose of all this being to diffuse heat at the very moment when it is generated and to transfer it to the body or environment to be heated by radiation, there being a minimum thermal head and dimension difference between the diffusing surface and the environment and body to be heated.

2. System as in claim 1, characterized in that the conductors are films made by electroplating.

3. System as in claim 1, characterized in that the conductors are laid serpentinewise.

4. System as in claim 1, characterized in that the conductors are laid in circular, square o rectangular spirals or in some other way.

5. System as in claim 1, characterized in that some lengths of the conductors are respectively of a constant or different cross-section according to values of temperature and to the amount of heat to be obtained in various lengths dimentional variations being gradual or sudden, according to preference or as the case may be.

6. System as in claim 1, characterized in that the various lengths of the conducorts are fed by electric current of the same or different values, variations in values being gradual or sudden according to preference or the case may be.

7. System as in claim 1, characterized in that the intensity of the mains electric current is increased by transformers.

8. System as in claim 1, characterized in that conducting bodies are placed around enclosed spaces where temperatures higher than the environmental levels are to be reached to obtain phisical or chemical transformation of materials.

9. System as in calim 1, characterized in that the conductors are placed at the internal walls and floor, of various kind of tanks into which fluid material is poured.

10. System as in claim 1, characterized in that the conductors are placed at the sides, floors, roof and other internal surfaces of vehicles.

11. System as in claim 1, characterized in that the conductors are palced at the internal surfaces of pans and cooking receptacles, containers generally for cooking or phisical and chimical transformation of materials.

12. Apparatuses (10, 30, 40, 50, 70, 90, 102) for generating and diffusing heat to the environment and to the fluids and solid bodies in general converting electrical energy into thermal energy, by means of the system descsribed in claims 1-11.