KR830002548B1 - Manufacturing method of double insulated wire for coil - Google Patents

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Description

Manufacturing method of double insulated wire for coil

The present invention relates to the production of a winding wire having two insulating layers by different materials. The characteristics of the windings insulated by varnish are well specified in the German test standard DIN 46435 (April 1977). Such windings are used on a large scale in the manufacture of electrical equipment or transformers.

Conductive materials such as copper and aluminum are insulated by a thin but mechanically and thermally stable and resistive synthetic varnish layer. The production of such varnished wires is accomplished by the continuous application of varnish to the metal wire several times. The solvent containing the varnish painted on the line is added with a dispersant as well as an aqueous solution of the varnish resin. However, all known processes were difficult to work with and required to spend a lot of time because of the slow speed of performing the process. The injection of thermoplastics into the production of thick walls and red wire that coat long electrical conductors is well known in the cable industry.

A process for producing varnished insulated wires by injecting thermoplastic plastics with melting points above 170 ° is described for the German Aussie Lift 2,638,763. Good temperature is above 250 ℃. This old technique plays a decisive role in overcoming the prejudice that the thin insulating layer required by the German test standard DIN46435 cannot be made by the injection process.

The process according to Auschleichleaf 2,638,763 in Germany and the process applied to the present invention has significant advantages, which saves time and energy by eliminating the need for further treatments such as taut or curing reactions. As in the manufacture of electrical appliances and electronics, there is a need for a second layer of different polymers on top of an insulated layer to provide a process guarantee of a coil that is particularly effective in electrical engineering. In addition, it requires not only the characteristics of the insulated wire to be stuck even after it is damaged by the solvent treatment, but also an increase in the rigidity of the surface and resistance to peeling.

This was generally satisfied by using a heat stable resin such as terephthalic acid polyester or polyester amine resin as the basic insulating lacquer. However, these resins were dried after being applied to the line several times in a conventional varnish machine. The second layer was also lined in the same way by linear, molecular coatings such as polyamide, polyvinyl acetal, and polyester.

A disadvantage of this process is that the linear polymer applied has some solubility so that the applied paint can be used in solids, which requires aggressive solvents that may affect the basic insulation of the conductor. It is an object of the present invention to provide a method of producing a wound wire having two insulating layers of different materials by applying an injection process and further to present a process of making a double coated wound wire. The outer coating here is a thermoplastic or almost insoluble polymer. It is also an object of the present invention to provide a winding line in which the outer coating has a double coating made by an injection process. Various advantages of the invention are described in detail below.

The present invention provides a method of producing a two-layer wound wire by injecting a thermoplastic material over an insulated electrical conductor coated with a varnish, resin, or partially crystalline or amorphous thermoplastic applied to an existing line. . An improvement is the injection of thermoplastics to coat a second layer over the first layer in contact with the electrical conductor. The total thickness of the two layers may be less than about 200 micrometres, and less than 150 micrometres or 100 micrometres, meeting the German test standard DIN 46435.

Thermoplastics include polyvinyl acetals, such as partially crystalline or amorphous polyamides or polyvinyl butyral, and the electrical conductor is copper or aluminum.

The first insulating layer on the conductor is an existing varnish, line varnish resin or partially crystallized or amorphous thermoplastic condensate, and the covered second layer is made of an extruded thermoplastic material.

Suitable injectable thermoplastics are suitable not to dissolve more than 10% by weight in solvent, even better to dissolve in 1% by weight in solvent, and best to dissolve less than 1/10% by weight. Other suitable thermoplastics are partially amorphous polyamides such as polyvinyl butyral or polyvinyl acetal.

The total thickness of the first and second layers can be less than 200 micrometers and less than 150 or 100 micrometers, meeting the German test standard DIN 46435.

The present invention consists of a combination of the elements presented in the preparation examples and subsequent steps, the method of which is described below. According to the present invention, a second layer of thermoplastic material is applied over an insulated electrical conductor by the injection of a varnish or varnish resin, or partly amorphous thermoplastic condensate, onto an existing line.

The basic insulation of electrical conductors is usually suited to known varnishes or varnish resins, which can be used to produce thermally stable windings of forms M.W 155 and W180 in accordance with Part 1, 4 and 5 of German Test Standard 46415.

In particular these include varnishes and varnishes based on terephthalic acid polyesters, polyesterimide, polyamide-imide, polyimide.

Enhance mechanical properties such as peeling or elastic modulus. Particularly suitable are partially crystallized or amorphous polyamides. Examples of partially crystallized polyamides include lactams, 6-polyamides, 11-polyamides, 12-polyamides, as well as 6-6 polyamide 6,10-polyamides and aliphatic dicarbonate acids and aliphatic diamides. Likewise, they are substances obtained by condensation from amides by W-aminocarbonic acid. Amorphous polyamides are suitable as follows. Examples include terephthalic acid or dimethyl terephthalate, transparent polyamides from trimethyl-hexamethylene-diamide (a mixture of 2,2,4 and 2,4,4 isoma), caprolactam hexamethylenediamine / adipic acid and Mixed polyamides based on pp-diaminodicyclohexylmethane / idic acid as well as tricomponent mixed polyamides, as well as several components having a glass temperature between 100 ° C and 200 ° C.

Such varnish resins are soluble in water and organic solvents, can be dispersed therein, and can be used after being dissolved.

Partially crystallized thermoplastic polycondensates are specified in German Auregeshlift PE-AS 2,638,763, examples of which are linear polyesters, polyamides, amorphous polytersulfones, and in the present invention the partially crystallized polyetherketones are used for injection molding. It is suitable for basic insulation of electrical conductors in coating. These polycondensates can be used in admixture with colorants, pigments, fillers and other auxiliaries if desired.

The present invention is used in the second layer, in which the thermoplastic material is softer at lower temperatures than the polycondensate of the first layer. In principle all thermoplastics which can be injected are suitable for the insulating layer of the second layer of the invention. If desired, an adhesive intermediate is applied to the base layer or heated to promote adhesion between the two insulating layers. Indeed, such a polymer is applied, which is heated up or dried using a volatile solvent, which, as can be seen in the case of hardening of the surface or in many instances, is particularly useful as a second layer where polyamide flows at a moderately raised temperature and It offers the property of baking coils or coils used in appliances and appliances. This eliminates the need for the application of other soaking varnish resins.

An example of an application for the second layer is polyvinyl acetals, which is particularly suitable in this class because of its ability to expand in volatile solvents such as alcohols. Volatile solvents provide a modified method for thermal drying as mentioned above.

Especially suitable are polyvinyl butyrals with a degree of butylarilation of 70-80%. The average molecular weight at this time is about 3000-20000. The decisive advantage of the present invention is the use of polymers, which are almost insoluble in common solvents.

A device for carrying out the invention is described in Ausregeshlift 2,638,763, Germany, a better device being titled the injection device for the production of a winding line in the Swiss patent application CH8446 / 76.

Both the base layer and the cladding layer are carried out by an injection process by the same apparatus, and the basic insulation is first coated on a line and then the second layer is introduced, or two layers are applied simultaneously in a work process by connecting injection machines in series. . The process conditions for several properties of the winding line as well as the individual polymer systems when coated by the apparatus detailed in the Swiss patent application are indicated in the following examples. 1-4 is an example of a smoothly heated 0.6 diameter copper wire, where the line is unrolled, first passing through the heating zone, through the coating zone, and then through the stripping nozzle of the injection machine head to adjust the coating thickness. The line covered past the cooling zone is wound, applying to the second layer coating. In each case the temperature of the injection machine is mentioned along the path from the inlet to the nozzle. The last three temperature values are mentioned for the nozzle system.

Example 1

Cover material:

1 layer: polyethylene ether phthalate (with pigment of 8% by weight titanium dioxide),

Second layer: 12-polyamide (polymer from laurolactam with a melting point of about 180 ° C.).

Process condition stratification system (diameter increase)

Injection temperature 1F: 34μm

1st floor: 240/250/260/270/280 ℃ 2nd floor: 30μm

Second floor: characteristics of 165/180/180/190/200/220 ℃ winding line

Withdrawal Speed Hardness: B

1st floor: 200 / min Softening temperature: 245 ℃

2nd floor: 200m / min

The high modulus and good adhesion of the cladding proved to be no cracks in the line when the line was pulled to the break point (23%).

Tin-plated ability: Lead 60/40 at 375 ° C: 3.5 seconds

Lead 60/40 at 475 ° C .: 2.0 sec.

Breakdown voltage: 5.0KV (according to DIN 46453, part 1 section 13. 2. 2.)

Drying Temperature: (DIN 46453, Part 1, Section 18. 2. 1.) 200 ° C

Softening Temperature: (DIN 46453, Part 1, Section 18. 2. 2.) 130 ℃

Example 2

As in Example 1, the diameter of the line only (0.6 mm) was no crack.

Breakdown voltage (according to DIN 46453, section 13. 2. 2.): 8.0KV

Drying temperature (DIN 46453, section 18. 2. 1.): 200 ℃

Smelting temperature (DIN 46453, section 18. 2. 2.): 125 ℃

Example 3

Coating material

1st floor: Formula of polyether ketone

2nd layer: 12-polyamide (as in Example 1)

Process condition withdrawal speed

Injection temperature 1F: 200m / min

1st floor: 390/410/420/420/420/440 ℃ 2nd floor: 100m / min

2F: 165/180/180/190/200/220 ℃ Layer Thickness (Increase in Diameter)

Evacuation Speed 1F: 44μm

1st floor: 200m / min 2nd floor: 22μm

2nd floor: Total increase of diameter 200m / min: 66μm

Layer thickness: (increase of diameter) characteristics of winding line

1F: 42μm Hardness: H

2nd floor: 36μm 20% Pull out: No crack.

Total increase in diameter is 78 μm

Baking Test:

Dip the ends of the two wires into the solvent for 5 seconds without touching them, then squeeze each other to determine if they adhere well to the wire. When methanol and ethanol were applied, they adhered well.

Example 5

For a 0.95mm diameter copper wire of W155 / W180 type varnished by the usual method, the total thickness of the insulated wire is 1.005mm, and the thickness of the first insulating layer is 55μm.

The characteristics of this line are as follows.

Pencil Hardness: 4H

After pulling out 25% (0.95mm diameter): several cracks are formed

20% pulling out (0.95mm diameter): 170 cracks.

Peel Test: 170 turns

Injection temperature: 210/240/265/280/275/270/280/300 ℃

Softening temperature (according to DIN 46453): 340 ℃ Evacuation temperature: 50m / min

Thermal shock (according to DIN 46453): 200 ° C Nozzle Diameter: 1.09mm

Coating material of the second layer: amorphous low viscosity polyamide

Layer thickness (diameter increase): characteristics of 64㎛ line for two layers

Density (dry): 1.14 pencil hardness, upper layer: HB

Melting Point (DIN 53736): 200 ℃ Lower Layer: 4H

Working condition

After pulling out 25% of wire (for 0.95mm wire): No crack.

Peel test: 250 rotational thermal shock (DIN 46453): 200 ℃

Softening Temperature (DIN 46453): 340 ℃

Baking temperature (DIN 46453, part 1, section 18. 2. 1): 220 ° C

Resoftening Temperature (DIN 46453, Part 1, Section 18. 2. 2.): 136 °

Example 6

In the case of 0.40 mm insulated wire varnished with polyesterimide in the usual way

Total diameter of insulated wire: 0.430mm 25% Pull back wire: No crack.

Increase in diameter by basic insulation: 30㎛ softening temperature (DIN46453): 285 ℃

Line Characteristics: Thermal Shock (DIN 46453): 250 ℃

Surface Hardness (Pencil Hardness): 4H to 5H

Coating material of the second layer

Amorphous polyamine transparent from dimethylterephthalate and trimethylhexamethylene diamide (mixture of isomers consisting of 2.24 and 2.44 trimethylhexamethylenediamine)

Characteristics of working conditions

Injection temperature: 310/300/290/280/280/300 ℃ Surface hardness (pencil hardness): 3H

Withdrawal speed: 200m / min after pulling 25% Line: No crack.

Nozzle Diameter: 0.445mm Softening Temperature (DIN 46453): 250 ℃

Increased diameter of 2 layers: 16㎛ thermal shock (DIN 46453): 250 ℃

Total increase diameter: 46㎛

Baking Temperature (DIN 46453, Part 1, Section 18. 2. 1.): 170 ° C

Resoftening Temperature (DIN 46453, Part 1, Section 18. 2. 2.): 136 ° C

The subject matter of the present invention has been sufficiently described without further analysis, and thus it is possible to apply it without departing from the aspects constituting the general and special features of the present invention with other knowledge.

Claims (1)

In the method for manufacturing a coil conductor wire having a double insulating layer formed of a different material, it is coated with a known conductor varnish or compressed and coated with a partially crystalline or amorphous thermoplastic polymer, and then insulated from the thermoplastic wire. A method of fabricating a double insulated wire for a coil, wherein the material is extruded to form a second insulating layer while the total thickness of the two insulating layers is less than 200 microns.