Multilayer connector with enameled insulated conductors

Abstract

A method of manufacturing a connector device suitable for making an inter or intra static electrical energy converter connection. The device includes at least two flat conductors and at least one insulating material. The said method includes: preparing each flat conductor individually; applying at least one coat of enamel varnish to each conductor, which is thinner than a desired final thickness; carrying out cross-linking of the enamel coating; and repeating the depositing of a layer of enameling resin and the cross-linking until the chosen thickness is reached. The varnish coated conductors of the connector device are assembled by using a template and connecting elements.

Claims

1. A method of manufacturing a connector device suitable for making an inter or intra static electrical energy converter connection, said device comprising at least two flat conductors and at least one insulating material, said method comprising: preparing each flat conductor individually; applying a layer of enamel varnish in liquid form of less than a desired final thickness to each conductor; cross-linking the enamel coating layer; applying at least one additional layer of enamel varnish in liquid form and cross-linking the at least one additional layer until the desired final thickness is reached to form the at least one insulating material; and assembling the conductors, coated with varnish, of said connector device.

2. The method of manufacturing the connector device according to claim 1, further comprising placing a mask on each zone of the conductor where an electrical contact is to be established before applying the varnish in liquid form.

3. The method of manufacturing the connector device according to claim 1, wherein the varnish layer is applied in fine particles, using a gas as propellant, or by pressure.

4. The method of manufacturing the connector device according to claim 1, wherein the varnish layer is applied by dipping or spraying.

5. The method of manufacturing the connector device according to claim 1, wherein the varnish layer is applied by centrifugal coating.

6. The method of manufacturing the connector device according to claim 1, wherein the cross-linking of the varnish is carried out by evaporation of solvent or by chemical reaction with a curing agent or by UV action.

7. The method of manufacturing the connector device according to claim 1, wherein different layers of the varnish applied are of different types and/or thicknesses.

8. The method of manufacturing the connector device according to claim 1, wherein the conductors coated with enameled varnish are assembled by using mechanical parts made of insulating material.

9. The method of manufacturing the connector device according to claim 1, wherein the conductors coated with the enamel varnish are assembled by using adhesive.

10. The method of manufacturing the connector device according to claim 1, further comprising inserting a sheet of insulating material between two conductors coated with the enamel varnish.

11. A connector device suitable for making an inter or intra static electrical energy converter connection, said device comprising: at least two flat conductors; and at least one insulating material applied to each of the at least two flat conductors, wherein the insulating material comprises a plurality of layers of enamel varnish, each layer of enamel varnish being applied in liquid form and being cross-linked, and the plurality of layers together having a desired thickness, and wherein the at least two flat insulated conductors are assembled.

12. The connector device according to claim 11, wherein the enamel varnish comprises at least one filler in the form of inorganic particles.

13. The connector device according to claim 11, wherein the enamel varnish comprises colored pigments.

14. The connector device according to claim 11, wherein the connector device is an inter or intra static electrical energy converter connector.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention shall be clearly understood by means of the following description (by way of a non-limitative example) of the drawings illustrating the interconnection device and the associated manufacturing process.

(2) FIG. 1 shows two independent conductors, provided with protection masks for the electrical connection areas.

(3) FIG. 2 shows two conductors, still independent, which have undergone the enamelling operations required by the process. The masks have been withdrawn. An enlarged section shows the detail of the stacking of the layers of varnish.

(4) FIG. 3 shows the two previously enameled conductors assembled with glue pads to form the multilayer connector with enameled insulated conductors.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

(5) A multilayer connector device (1) is produced by means of the method according to the invention, which device (1), according to FIG. 1, is manufactured from at least one flat conductor (2), on which a spark gap (3) is optionally placed in each area of said conductor (2) where an electrical contact is to be established. The spark gap (3) may be placed on one side of the conductor (2), or may be through-going, at the level of a slot (4) made in said conductor (2).

(6) Depending on the manufacturing process, the application of spatter(s) is carried out before applying the varnish (10). As shown in FIG. 2, one or more layers (11, 12) of enamel varnish (10) are applied to the prepared conductors (2) and possibly provided with spacers (3). When the spacers (3) are removed, for example, holes (4) with varnish coating on the edges (hole (4) with thick edge on the lower conductor (2)) and holes with varnish coating on the edges of the holes protected by the spacers (3) (hole (4) with thin edge on the upper conductor (2)) are obtained.

(7) Preferably, each conductor is individually coated with at least two layers of enamel varnish (10) in liquid form, subsequent layers are created only if the previous layer is cross-linked.

(8) Enamel varnish (10) is a resin with special properties of adhesion to the electrical conductor, electrical resistance and thermal stability.

(9) Most preferably, the enamel varnish (10) comprises at least one filler in the form of inorganic particles preferably smaller than 150 μm in size, such as for example: silica (SiO2), alumina (Al2O3), magnesia (MgO). Thanks to this inorganic filler, the resin exhibits less alteration of its electrical characteristics under partial discharge stress. This technical possibility makes it possible to obtain a controlled service life in the presence of partial discharges, contrary to current technology which requires the absence of partial discharges.

(10) Advantageously, the characteristic parameters of said enamel (10) are selected from:

(11) dynamic viscosity: 100 to 4000 mPa.Math.s, and/or

(12) temperature class: 120° C. to 240° C. (120/140/155/180/200/220/240° C.), according to IEC 60085: 2007, and/or

(13) dielectric strength greater than or equal to 30 kV/mm, and/or

(14) more preferably the chemical nature is chosen among: polyurethane (PUR), thermoplastic elastomer (TPE).

(15) As an example, enamel varnish (10) can be chosen from the VOLTATEX WIRE® range (Dupont).

(16) Enamelling varnish (10) can be cross-linked by the action of heat or by the action of Ultra Violet rays. For the latter, Green Isolight International can be chosen as an example:

(17) the GII 206 which has a class of 180° C. and is based on polyester acrylate;

(18) the GII 200 which has a class of 120° C. and which is polyalcohol modified acrylate.

(19) To apply Coating (10), for example, Conductor (2) can be suspended by means of a hook that grips on a spacer 3.

(20) The varnish (10) can then be sprayed onto the conductor (2).

(21) The coating can be applied in the form of fine particles, by aerosol effect using a propellant gas (air or neutral gas such as nitrogen, for example) or by pressure.

(22) Conductor (2) can also be dipped in a bath or sprayed with varnish (10). Another possibility is to apply the varnish by centrifugal coating.

(23) Preferably, thin layers are applied to multiply the number of layers. The technical specialist will be able to determine the parameters necessary to achieve the desired thickness according to the characteristics of the varnishes used.

(24) Preferably, according to the process, the assembly stage of said device (1) comprises at least one stage among: gluing stage(s), mechanical clamping stage(s).

(25) Gluing (gluing step) includes for example: press gluing and/or hot-melt gluing and is carried out using a glue such as: transfer film adhesive, liquid glue.

(26) Advantageously, the process according to the invention is remarkable in that: first of all, a layer of enamel resin (10) of thickness A is applied, preferably by dipping followed by dripping (however, any other suitable method—depending on the chosen varnish (10)—can be used, such as spraying or centrifugal deposition), then said enamel varnish (1)0 is crosslinked and the deposition and crosslinking is repeated.

(27) The technical specialist knows how to choose the number of iterations of the step cycle presented above, so as to obtain a desired final thickness B of enamel varnish (10), coating said flat conductors (2). Among other things, the number of iterations (and therefore the final thickness B) is chosen according to the voltage that device (1) must withstand.

(28) Preferably, the said thickness B is between 30 and 200 microns, in order to enable the device to operate at a voltage of between 300 and 1250 volts. Preferentially, said thickness A is between 3 and 15 microns.

(29) A first benefit of these different stages A of enameling resin (varnish) deposition (10) is to avoid the creation of microcavities in the thickness of the insulation (any microcavity being likely to become the location of partial discharges that are detrimental to the durability of the electrical performance of the insulation and/or the insulation.

(30) A second benefit is to reduce the risk of an accidental localized lack of varnish (10) because the layers are applied independently of each other.

(31) A third will be to take advantage of the specific characteristics of each type of coating (10), for example a first layer with a high adhesion capacity on conductive surfaces, a subsequent layer with higher mechanical performance, or an identification coloured coating (10) layer (e.g. coating with coloured pigments; this technical possibility allows unambiguous identification of one conductive layer compared to another).

(32) The cross-linking of the enamel varnish coated (10) can, for example, take place spontaneously at room temperature or in an oven, by solvent evaporation, by chemical reaction with a curing agent, or under the influence of UV radiation.

(33) Depending on a variant of the process, the different layers of varnish (10) applied are of different types and/or thicknesses.

(34) Advantageously, according to a variant (joining step) of the process, the conductors (2) coated with enamel (10) varnish are joined together by means of mechanical parts made of insulating material.

(35) In another variant (joining step) of the process, the conductors (2) coated with enamel varnish (10) are joined together by means of adhesive in any form.

(36) Preferably, as shown in FIG. 3, one or more insulating spacers, such as a sheet of insulating material (15) (e.g. mica), is inserted between two conductors (2) coated with enamel varnish (10).

(37) Advantageously, the method according to the invention is remarkable in that in advanced variants of the preparation step for flat conductors (2), it further comprises at least one surface preparation step, chosen for example from among others: degreasing, dust removal.

(38) Also, the proposed process makes it easier to consider a global ecological approach, by offering the possibility of using aqueous solvents instead of organic solvents in varnishes.

(39) Finally, the invention concerns any device obtained by the previously described process, comprising at least two flat conductors (2) and at least one insulating material: varnish (10) (possibly in multilayer form (11, 12)), spacer (15).

(40) Although the present disclosure has been described with reference to one or more examples, workers skilled in the art will recognize that changes may be made in form and detail without departing from the scope of the disclosure and/or the appended claims.