Double anti-parallel heating winding

Abstract

Double anti-parallel heating coil The present invention relates to a device for electrical heating by means of an electrically heated cord in the form of a double anti-parallel coil. Preferably, the rear parts of the turns are made non-heating by establishing crossed electrical connections between the start and the end of the rear parts of the turns of one coil with the start and the end of the rear parts of the corresponding turns of the other coil. The invention is particularly suitable for heating premises and more particularly for heating by infrared radiation. Figure to be published for the abstract: [Figure 3]

Description

Title of the invention: Double anti-parallel heating coil

[0001] FIELD OF THE INVENTION The present invention relates to a device for electrically heating premises by means of a double winding of an electrically heated cord where double winding means two windings electrically insulated from each other, with geometrically nested parallel turns, supplied with the same voltage +V,-V and anti-parallel in the sense that the current in one and the other flows in parallel but in opposite directions.

[0002] BACKGROUND OF THE INVENTION Heating premises using electrical energy essentially uses the Joule effect in an electrical resistive element powered by electrical connectors from an electrical energy source. The transfer of heat to the premises, the air and the occupants occurs by thermal conduction and / or convection and / or infrared radiation emitted by the electrical resistive element due to its temperature.

[0003] The electrical resistive element may be in a generally 2D form, for example in the form of one or more turns located in a plane or on a convex or concave surface. The electrical resistive element can also be in a 3D form, in particular in the form of one or more windings (coil) of a resistive cord on a core, for example made of ceramic. The core can be, for example, cylindrical in shape with a director in the form of a circle or a very flattened ellipse or a polygon with rounded corners. The core can be a solid solid body or a hollow body, generally the resistive element has proximity and or extensive contact with the mass of the core. The core may be structured, for example comprising at its periphery longitudinal beams distributed radially regularly at the vertices of a regular polygon, thus allowing support of the ribbon by means of the contact of the ribbon with the beams and the absence of contact of the ribbon with the core in the inter-beam spaces. In the case where the heating cord is in the form of a coil, in particular a flat coil, it is desirable not to lose the power potentially emitted by the rear parts of the coils, i.e. the parts of the coils which are opposite the walls or the ceiling as opposed to the front parts which are opposite the walls or the ceiling. with regard to the volume of the room to be heated and capable of emitting power directly towards the volume of the room. One solution consists of placing a reflector capable of returning the power radiated by the rear parts towards the front, i.e. towards the volume of the room. Another solution consists of shunting by, i.e. connecting in parallel with the rear part of the turns between the start and the end of the turn, a very low value resistor, thus greatly reducing the power dissipated in the rear part of the turns. The start and end of the turns are understood to be the areas of the turn where the orientation changes from the front (towards the room) to the rear (towards the walls).

[0004] A resistive cord may be, for example, non-limitingly, of cylindrical section in the case of the winding of a conductive wire bearing an insulating varnish or, for example, of rectangular section in the case of the winding of a ribbon. An example of a heating cord winding is a winding of a cupro-nickel wire of circular section of 1 mm in diameter with a pitch of 2 mm. Another example of a resistive cord winding is a winding of a stainless steel or aluminum alloy ribbon where the width of the ribbon is between 25 mm and 50 mm, typically having the value of 30 mm, and where its thickness is between 15 micrometers and 100 micrometers, typically having the value of 20 micrometers with a pitch of 35 mm. Another example of a resistive cord winding is a ribbon made of polymeric material such as polypropylene or PET.or Teflon 50 micrometers thick and 25mm wide, aluminized on at least one of its faces to a thickness of 5 micrometers.

[0005] DETAILED DESCRIPTION OF THE INVENTION The invention presented below makes it possible to heat a room with a heating cord in the form of windings, preferably flat, the rear part of the turns of which emits only very low power. Our invention makes it possible to avoid the disadvantages of the aforementioned solutions, namely the thermal reflector and its size and cost, the shunt which requires the production of an electrical conductor from the start to the end of each turn. The device which is the subject of the invention [Fig.l] comprises a double winding of heating cord where double winding means two windings electrically insulated from each other, with geometrically nested parallel turns, supplied by the same voltage +V, -V and anti-parallel in the sense that the current in one and the other circulates in parallel but in opposite directions

[0006] A correspondence is defined between the turns of one and the other winding: two turns are said to be corresponding if the upper potential point of one and the other turn are at the same distance in terms of electrical resistance from the connection pad +V. The device which is the subject of the invention is characterized in that: The beginning and the end of each rear part of each turn of a winding are connected in a crossed manner by conductors, called crossed conductors, quasi-equipotential, that is to say of very low resistance, to the beginning and to the end of the rear part of the corresponding turn of the other winding. [Fig.2] illustrates this type of electrical diagram, [Fig.3] illustrates a double winding as defined in our invention with in symbolic form the quasi-equipotential connections between the beginning and the end of the turns as defined above. The advantage of our invention is that the crossed conductors are located entirely in both the start and end zones of the windings and therefore without crossing the space between the start and the end.

[0007] The following description, given without limitation, is an example of implementation of our invention.

[0008] The double winding is a double winding of flat ribbon. Each winding is flat, that is to say that the dimension between the start and end of the turns is significantly greater than the thickness, that is to say the distance measured perpendicularly between the front part and the rear part of the turns. Two cylindrical uprights are positioned at the start of the turns and the end of the turns and the ribbon of each winding is in contact with the uprights in the part of the circumference of the uprights facing the outside of the winding. In other words, the ribbon makes approximately half a turn around the upright. The structure of the uprights is used not only to provide the primary function which is the mechanical maintenance of the windings but also to provide an individual electrical contact for each turn of each winding, and also to provide the possibility of establishing equipotential connections between pairs of turns in order to produce all the crossed conductors Each upright comprises over its entire length a cylindrical core made of insulating material comprising at its periphery rounded longitudinal grooves, preferably substantially quarter-cylinder in shape, each intended to accommodate a flexible, elastic and electrically conductive blade, for example made of copper, brass or aluminium, of flat shape when at rest and quarter-cylinder in shape once inserted, the width r of which has two levels: the general level over the greater part of the length is such that once inserted into the groove its upper part remains set back from the cylinder of the core and the contact level over two segments of the length, corresponding to the position of the turns that it is desired to electrically connect and of a length less than or equal to the width of the strip.The contact level being such that once inserted into the groove the upper part of the flexible blade is likely to be able to protrude relative to the core cylinder. Once equipped with all the flexible blades corresponding to all the equipotential connections to be made, the cylindrical core is equipped with sections of conductive tubes of length corresponding to the width of the strip, positioned longitudinally so as to coincide with the position of the turns at the level of the upright and insulated from each other, preferably using insulating washers positioned between said tube sections. The internal diameter of each tube section corresponds to the diameter of the insulating core, thus allowing good electrical contact with the flexible blade, the contact part of which corresponds to the position of said section.

[0009] BRIEF DESCRIPTION OF THE DRAWINGS Other objects, characteristics and advantages of the invention will be better understood in light of the detailed description which follows, with reference to the appended drawings in which:

[0010] [Fig.l] represents a double winding corresponding to the invention. The support core for the windings and / or any uprights are not shown. For better readability and understanding, arrows (13) indicate the direction of the current in one (11) and the other (12) winding. It can thus be seen that the two windings are anti-parallel. [Fig.2] shows the electrical connection diagram of the turns according to the invention in the form of a network of connected resistors. The resistors (211) represent the rear parts of the winding 1 while the resistors (221) represent the rear parts of the winding 2. The conductors (23) represent the crossed conductors.

[0011] Similarly, the resistors (212) represent the front parts of the winding 1 and the resistors (222) represent the front parts of the winding 2.

[0012] [Fig. 3] shows a double winding (31) and (32) of ribbon according to the invention with the equipotential connections (33) between the turns representing the said crossed conductors presented in the symbolic form of lines. [Fig.4] shows a double winding (41) and (42) of ribbon according to the invention extending from one upright (43) to the other upright (44). To facilitate understanding, each of the uprights is also shown at a distance from the double winding. On each of these windings, the set of sections (45) of conductive tube can be seen, positioned longitudinally so as to coincide with the position of the turns. [Fig.5] shows an upright with its constituent elements The insulating core (51) with its eight grooves (52), a flexible blade in its rest position (531) and the same blade (532) as it appears once inserted into its groove, eight of the sixteen sections (54) of conductive tube which can potentially be installed, in position on the insulating core (51) in electrical connection between them by their contact of their inner periphery with the upper parts of the flexible blade (532); a reduced section (56) of length of the upright at the level of one of the contacts is presented. A set (55) of blades are presented in their position corresponding to the groove in which each must be inserted but at a distance from the core and its grooves for reasons of readability

Claims

Claims

1. Electric heating device using a resistive cord, characterized in that said device comprises two windings of said resistive cord, nested and antiparallel.

2. Claim according to 1 wherein the beginning and the end of the rear part of each turn of one winding are cross-connected by electrical conductors to the beginning and the end of the rear part of the corresponding turn of the other winding

3. Claim according to 1 to 2 where the resistive cord is a conductive strip whose thickness is significantly smaller than its width.

4. Claim according to 1 to 3 where the thickness of the windings is significantly less than their extension between the start and the end of the turns

5. Claim according to 3 and 4 where the ribbon is made of aluminum alloy or iron alloy or aluminized polymeric material.

6. Claim according to 1 to 5 where the two windings extend between two cylindrical uprights by making a half turn around the uprights

7. Claim according to 6 where each upright comprises an insulating core hollowed out with rounded grooves capable of receiving flexible conductive blades.

8. Claim according to 7 where the conductive blades have a width structured so as not to exceed the groove in the lower parts and to exceed the groove in two so-called contact parts.

9. Claim according to 6 to 8 where sections of conductive tube insulated from each other and with an internal diameter substantially equal to the diameter of the insulating core are placed longitudinally on the core at longitudinal positions corresponding to the position of the passage around the amount of the turns of one and the other winding.

10. Claim according to 8 where the longitudinal position of the two contact parts of each blade correspond to the position of the passage around the upright of two corresponding turns within the meaning of claim 2

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