CN105869698A

CN105869698A - Enameled wire and manufacturing method thereof

Info

Publication number: CN105869698A
Application number: CN201610303499.2A
Authority: CN
Inventors: 王笑梅
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-05-10
Filing date: 2015-05-10
Publication date: 2016-08-17
Also published as: CN104821189A; CN105931695A; CN104821189B; CN106024089A

Abstract

The invention belongs to the technical field of conductors and enameled wires and particularly relates to an enameled wire. The enameled wire is composed of an inner conductor, an outer conductor covering the whole inner conductor, and a paint layer arranged outside the outer conductor in a coating mode. The enameled wire is characterized in that the outer conductor is made of copper, the inner conductor is made of aluminum or alloy, the cross section of the inner conductor is rectangular, the cross section of the outer conductor is circular, the center of the inner conductor and the center of the outer conductor coincide, on any cross section of the enameled wire, the rectangular area of the inner conductor is 55-65% of the circular area of the outer edge of the outer conductor, and the thickness of the paint layer ranges from 1 micrometer to 10 micrometers. The invention further discloses a manufacturing method of the alloy enameled wire and paint for the enameled wire. The enameled wire has the advantages of being low in weight, resistivity and transport cost, capable of keeping acceptable temperature rise when running with a heavy load for a long term, and the like.

Description

A kind of enamel-covered wire and manufacture method thereof

The application is entitled: a kind of enamel-covered wire with alloy inner wire and manufacture method thereof, division date of filing be: on 05 02nd, 2016, the divisional application of the patent of invention of Application No.: 201610279016.X；The application for a patent for invention of Application No.: 201610279016.X is filing date: on 05 10th, 2015, Application No.: the divisional application of the patent of invention of 201510233662.8.

Technical field

The invention belongs to conductor and enamel-covered wire technical field, especially relate to a kind of enamel-covered wire and manufacture method thereof.

Background technology

In prior art, enamel-covered wire is to be made up of copper wire and the insulating lacquer layer that is coated in outside copper wire, and this enamel-covered wire is widely used in the electric equipments such as the rotor of electric tool, electromagnetic stove coil, miniature transformer.Owing to the conductor in enamel-covered wire of the prior art is made up of copper, thus amount of copper consuming proportion relatively big, copper is higher, therefore, electrical equipment weight is relatively heavy, cost remains high.

Summary of the invention

In order to solve the problems referred to above, an object of the present invention is to disclose a kind of enamel-covered wire, and it has excellent electric conductivity and lighter in weight, cost is relatively low, can effectively substitute and use copper as the enamel-covered wire of conductor in prior art；The two of the purpose of the present invention are the manufacture methods disclosing a kind of enamel-covered wire；They realize by the following technical solutions.

In first embodiment of the present invention, a kind of enamel-covered wire, it is that the outer conductor by inner wire, inner wire integral coating lived, the enamelled coating that is coated in outside outer conductor are constituted；The material that it is characterized in that described outer conductor is copper, and the material of inner wire is aluminium or alloy, a diameter of d1 of inner wire, a diameter of d2 of outer conductor, enamelled coating the ratio of a diameter of d3, d1 and d2 more than or equal to 0.7416 and less than or equal to 0.8062；The difference of d3 Yu d2 is 2～20 μm.

A kind of enamel-covered wire described above, it is characterised in that the diameter of described inner wire is 0.7746 with the ratio optimal value of the diameter of outer conductor.

A kind of enamel-covered wire described above, it is characterised in that manufacture method comprises the steps of

The first step: take inner wire rod-shaped material and stretch, the cross section obtaining required size is the inner wire of rectangle；The material of inner wire is aluminum or aluminum alloy or magnesium alloy or almag, or the alloy material being made up of following weight portion: aluminium 98.5～99.3 parts, copper 0.3～0.4 part, silver 0.1～0.3 part, chromium 0.1～0.3 part, magnesium 0.1～0.3 part, zinc 0.1～0.2 part；Or take internal conductor material melt and carry out extrusion cooling shaping, the cross section obtaining required size is the inner wire of rectangle；The material of inner wire is aluminum or aluminum alloy or magnesium alloy or almag, or the alloy material being made up of following weight portion: aluminium 98.5～99.3 parts, copper 0.3～0.4 part, silver 0.1～0.3 part, chromium 0.1～0.3 part, magnesium 0.1～0.3 part, zinc 0.1～0.2 part；

Second step: outer conductor material is coated with in the conductor, then stretches, obtain outer conductor；Or it is coated with outer conductor material in the outer melt extrusion of inner wire, and cooling obtains outer conductor；Described outer conductor material is copper, and the cross section outer rim of outer conductor is circular, and the center of inner wire coincides with the center of outer conductor, on arbitrary cross section: the rectangular area of inner wire is the 55～65% of outer conductor outer rim circular area；

3rd step: at the outer coating paint layer material of outer conductor, is dried enamelled coating and coiling obtains alloy enamel-covered wire；The thickness of described enamelled coating is 1～10 μm；The material of described enamelled coating is that the material by following weight portion of polyurethane or polyimides or described enamelled coating is constituted: polyamic acid 3～6 parts, mutual-phenenyl two acid bromide two alcohol ester 2～4 parts, dimethylacetylamide 58～65 parts, '-diphenylmethane diisocyanate 15～20 parts, polyethylene terephthalate 12～16 parts, poly-amino resins 3～5 parts, ethyl acetate 4～5 parts, butyl acetate 3～4 parts, mica 4～5 parts, alundum (Al2O3) 2～2.5 parts, commercially available varnish 4～6 parts, ethanol 2～5 parts.

In second embodiment of the present invention, a kind of enamel-covered wire, it is that the outer conductor by inner wire, inner wire integral coating lived, the enamelled coating that is coated in outside outer conductor are constituted；The material that it is characterized in that described outer conductor is copper, the material of inner wire is aluminium or alloy, the cross section of inner wire is rectangle, the cross section outer rim of outer conductor is circular, the center of inner wire coincides with the center of outer conductor, on arbitrary cross section of enamel-covered wire: the rectangular area of inner wire is the 55～65% of outer conductor outer rim circular area, the thickness of enamelled coating is 1～10 μm.

A kind of enamel-covered wire described above, it is characterised in that on arbitrary cross section of described enamel-covered wire: the rectangular area of inner wire is the 60% of outer conductor outer rim circular area.

A kind of enamel-covered wire described above, the first step: take inner wire rod-shaped material and stretch, the cross section obtaining required size is the inner wire of rectangle；The material of inner wire is aluminum or aluminum alloy or magnesium alloy or almag, or the alloy material being made up of following weight portion: aluminium 98.5～99.3 parts, copper 0.3～0.4 part, silver 0.1～0.3 part, chromium 0.1～0.3 part, magnesium 0.1～0.3 part, zinc 0.1～0.2 part；Or take internal conductor material melt and carry out extrusion cooling shaping, the cross section obtaining required size is the inner wire of rectangle；The material of inner wire is aluminum or aluminum alloy or magnesium alloy or almag, or the alloy material being made up of following weight portion: aluminium 98.5～99.3 parts, copper 0.3～0.4 part, silver 0.1～0.3 part, chromium 0.1～0.3 part, magnesium 0.1～0.3 part, zinc 0.1～0.2 part；

A kind of enamel-covered wire described in any of the above-described embodiment, it is characterised in that when the material of described inner wire is alloy, described alloy is aluminium alloy or magnesium alloy or almag.

A kind of enamel-covered wire described in any of the above-described embodiment, it is characterised in that the material of described enamelled coating is polyurethane or polyimides.

A kind of enamel-covered wire, it is that the outer conductor by inner wire, inner wire integral coating lived, the enamelled coating that is coated in outside outer conductor are constituted；The material that it is characterized in that described outer conductor is copper, and the material of inner wire is aluminium or alloy, a diameter of d1 of inner wire, a diameter of d2 of outer conductor, enamelled coating the ratio of a diameter of d3, d1 and d2 more than or equal to 0.7416 and less than or equal to 0.8062；The difference of d3 Yu d2 is 2～20 μm；The material of described enamelled coating is to be made up of the material of following weight portion: polyamic acid 3～6 parts, mutual-phenenyl two acid bromide two alcohol ester 2～4 parts, dimethylacetylamide 58～65 parts, '-diphenylmethane diisocyanate 15～20 parts, polyethylene terephthalate 12～16 parts, poly-amino resins 3～5 parts, ethyl acetate 4～5 parts, butyl acetate 3～4 parts, mica 4～5 parts, alundum (Al2O3) 2～2.5 parts, commercially available varnish 4～6 parts, ethanol 2～5 parts.

A kind of enamel-covered wire, it is that the outer conductor by inner wire, inner wire integral coating lived, the enamelled coating that is coated in outside outer conductor are constituted；The material that it is characterized in that described outer conductor is copper, and the material of inner wire is aluminium or alloy, and a diameter of d1 of inner wire, a diameter of d2 of outer conductor, the ratio of a diameter of d3, d1 and d2 of enamelled coating are 0.7746；The difference of d3 Yu d2 is 2～20 μm；The material of described enamelled coating is to be made up of the material of following weight portion: polyamic acid 3～6 parts, mutual-phenenyl two acid bromide two alcohol ester 2～4 parts, dimethylacetylamide 58～65 parts, '-diphenylmethane diisocyanate 15～20 parts, polyethylene terephthalate 12～16 parts, poly-amino resins 3～5 parts, ethyl acetate 4～5 parts, butyl acetate 3～4 parts, mica 4～5 parts, alundum (Al2O3) 2～2.5 parts, commercially available varnish 4～6 parts, ethanol 2～5 parts.

A kind of enamel-covered wire, it is that the outer conductor by inner wire, inner wire integral coating lived, the enamelled coating that is coated in outside outer conductor are constituted；The material that it is characterized in that described outer conductor is copper, the material of inner wire is aluminium or alloy, the cross section of inner wire is rectangle, the cross section outer rim of outer conductor is circular, the center of inner wire coincides with the center of outer conductor, on arbitrary cross section of enamel-covered wire: the rectangular area of inner wire is the 55～65% of outer conductor outer rim circular area, the thickness of enamelled coating is 1～10 μm；When the material of described inner wire is alloy, described alloy is aluminium alloy or magnesium alloy or the alloy material being made up of following weight portion: aluminium 98.5～99.3 parts, copper 0.3～0.4 part, silver 0.1～0.3 part, chromium 0.1～0.3 part, magnesium 0.1～0.3 part, zinc 0.1～0.2 part；The material of described enamelled coating is to be made up of the material of following weight portion: polyamic acid 3～6 parts, mutual-phenenyl two acid bromide two alcohol ester 2～4 parts, dimethylacetylamide 58～65 parts, '-diphenylmethane diisocyanate 15～20 parts, polyethylene terephthalate 12～16 parts, poly-amino resins 3～5 parts, ethyl acetate 4～5 parts, butyl acetate 3～4 parts, mica 4～5 parts, alundum (Al2O3) 2～2.5 parts, commercially available varnish 4～6 parts, ethanol 2～5 parts.

A kind of enamel-covered wire, it is that the outer conductor by inner wire, inner wire integral coating lived, the enamelled coating that is coated in outside outer conductor are constituted；The material that it is characterized in that described outer conductor is copper, and the material of inner wire is the alloy material being made up of following weight portion: aluminium 98.5～99.3 parts, copper 0.3～0.4 part, silver 0.1～0.3 part, chromium 0.1～0.3 part, magnesium 0.1～0.3 part, zinc 0.1～0.2 part；A diameter of d1 of inner wire, a diameter of d2 of outer conductor, enamelled coating the ratio of a diameter of d3, d1 and d2 more than or equal to 0.7416 and less than or equal to 0.8062；The difference of d3 Yu d2 is 2～20 μm.

A kind of enamel-covered wire, it is that the outer conductor by inner wire, inner wire integral coating lived, the enamelled coating that is coated in outside outer conductor are constituted；The material that it is characterized in that described outer conductor is copper, and the material of inner wire is the alloy material being made up of following weight portion: aluminium 98.5～99.3 parts, copper 0.3～0.4 part, silver 0.1～0.3 part, chromium 0.1～0.3 part, magnesium 0.1～0.3 part, zinc 0.1～0.2 part；The cross section of inner wire is rectangle, the cross section outer rim of outer conductor is circular, the center of inner wire coincides with the center of outer conductor, on arbitrary cross section of enamel-covered wire: the rectangular area of inner wire is the 55～65% of outer conductor outer rim circular area, and the thickness of enamelled coating is 1～10 μm.

A kind of enamel-covered wire, it is that the outer conductor by inner wire, inner wire integral coating lived, the enamelled coating that is coated in outside outer conductor are constituted；The material that it is characterized in that described outer conductor is copper, and the material of inner wire is alloy, a diameter of d1 of inner wire, a diameter of d2 of outer conductor, enamelled coating the ratio of a diameter of d3, d1 and d2 more than or equal to 0.7416 and less than or equal to 0.8062；The difference of d3 Yu d2 is 2～20 μm；Described alloy is aluminium alloy or magnesium alloy or almag；The material of described enamelled coating is to be made up of the material of following weight portion: polyamic acid 3～6 parts, mutual-phenenyl two acid bromide two alcohol ester 2～4 parts, dimethylacetylamide 58～65 parts, '-diphenylmethane diisocyanate 15～20 parts, polyethylene terephthalate 12～16 parts, poly-amino resins 3～5 parts, ethyl acetate 4～5 parts, butyl acetate 3～4 parts, mica 4～5 parts, alundum (Al2O3) 2～2.5 parts, commercially available varnish 4～6 parts, ethanol 2～5 parts.

The preparation method of a kind of enamel-covered wire, it is characterised in that manufacture method comprises the steps of

The first step: take inner wire rod-shaped material and stretch, obtain the inner wire of required diameter；The material of inner wire is aluminum or aluminum alloy or magnesium alloy or almag；

Second step: outer conductor material is coated with in the conductor, then stretches, obtain outer conductor；Described outer conductor material is copper, makes the diameter of the inner wire ratio with the diameter of outer conductor more than or equal to 0.7416 and less than or equal to 0.8062；

3rd step: at the outer coating paint layer material of outer conductor, is dried enamelled coating and coiling obtains alloy enamel-covered wire；The thickness of described enamelled coating is 1～10 μm；The material of described enamelled coating is to be made up of the material of following weight portion: polyamic acid 3～6 parts, mutual-phenenyl two acid bromide two alcohol ester 2～4 parts, dimethylacetylamide 58～65 parts, '-diphenylmethane diisocyanate 15～20 parts, polyethylene terephthalate 12～16 parts, poly-amino resins 3～5 parts, ethyl acetate 4～5 parts, butyl acetate 3～4 parts, mica 4～5 parts, alundum (Al2O3) 2～2.5 parts, commercially available varnish 4～6 parts, ethanol 2～5 parts.

Therefore, the present invention has lightweight, low cost, low-resistivity, low cost of transportation, long-term heavy service can keep the Advantageous Effects such as acceptable temperature rise.

Accompanying drawing explanation

Fig. 1 is section plane of structure structural representation of embodiment 1 of the present invention.

Fig. 2 is section plane of structure structural representation of embodiment 2 of the present invention.

Detailed description of the invention

Embodiment 1

Asking for an interview Fig. 1, a kind of enamel-covered wire, it is that the outer conductor 2 by inner wire 1, inner wire integral coating lived, the enamelled coating 3 that is coated in outside outer conductor are constituted；The material that it is characterized in that described outer conductor is copper, and the material of inner wire is aluminium or alloy, a diameter of d1 of inner wire, a diameter of d2 of outer conductor, enamelled coating the ratio of a diameter of d3, d1 and d2 more than or equal to 0.7416 and less than or equal to 0.8062；The difference of d3 Yu d2 is 2～20 μm.

A kind of enamel-covered wire described above, it is characterised in that the diameter of described inner wire is 0.7746 with the ratio of the diameter of outer conductor.

A kind of enamel-covered wire described above, it is characterised in that when the material of described inner wire is alloy, described alloy is aluminium alloy or magnesium alloy or almag.

Embodiment 2

Asking for an interview Fig. 2, a kind of enamel-covered wire, it is that the outer conductor 2 by inner wire 1, inner wire integral coating lived, the enamelled coating 3 that is coated in outside outer conductor are constituted；The material that it is characterized in that described outer conductor is copper, the material of inner wire is aluminium or alloy, the cross section of inner wire is rectangle, the cross section outer rim of outer conductor is circular, the center of inner wire coincides with the center of outer conductor, on arbitrary cross section of enamel-covered wire: the rectangular area of inner wire is the 55～65% of outer conductor outer rim circular area, the thickness of enamelled coating is 1～10 μm.

A kind of enamel-covered wire described above, it is characterized in that when the material of described inner wire is alloy, described alloy is aluminium alloy or magnesium alloy or almag or the alloy material being made up of following weight portion: aluminium 98.5～99.3 parts, copper 0.3～0.4 part, silver 0.1～0.3 part, chromium 0.1～0.3 part, magnesium 0.1～0.3 part, zinc 0.1～0.2 part.

The alloy of above-mentioned formula, owing to comprising a small amount of silver, therefore conductive effect is greatly improved, and owing to comprising the compositions such as copper, therefore easily merges with outer conductor, and internal and external conductor interlayer phenomenon will not occur, and is conducive to improving electric conductivity and reducing temperature rising high-performance.

A kind of enamel-covered wire described in any of the above-described embodiment, it is characterised in that the material of described enamelled coating is any one paint vehicle that can be used for enamel-covered wire in polyurethane or polyimides or prior art.

A kind of enamel-covered wire described in any of the above-described embodiment, it is characterised in that the material by following weight portion of described enamelled coating is constituted: polyamic acid 3～6 parts, mutual-phenenyl two acid bromide two alcohol ester 2～4 parts, dimethylacetylamide 58～65 parts, '-diphenylmethane diisocyanate 15～20 parts, polyethylene terephthalate 12～16 parts, poly-amino resins 3～5 parts, ethyl acetate 4～5 parts, butyl acetate 3～4 parts, mica 4～5 parts, alundum (Al2O3) 2～2.5 parts, commercially available varnish 4～6 parts, ethanol 2～5 parts.

The coating of above-mentioned formula, relative to polyurethane or polyimide varnish layer material, there are higher insulating properties, more resistant to mill, being that the pressure using 10N wipes 5000 times repeatedly equally, the enamelled coating of the above-mentioned formula of same thickness is compared with polyurethane or polyimides enamelled coating, and polyurethane or polyimides enamelled coating all occur in that discolouration phenomena, and above-mentioned having no of formula is faded, it is seen that the enamelled coating of above-mentioned formula is higher more resistant to mill, adhesive force；Additionally, the thickness that the enamelled coating of above-mentioned formula is as polyurethane or the coating of polyimides enamelled coating, drying in same baking oven, the enamelled coating rate of drying of above-mentioned formula shortens 15～25% drying time average than contrast groups simultaneously.

A kind of enamel-covered wire in embodiment 1 of the present invention, it is characterised in that it is fabricated by by the following method:

The first step: take inner wire rod-shaped material and stretch, obtain the inner wire of required diameter；The material of inner wire is aluminum or aluminum alloy or magnesium alloy or almag, or the alloy material being made up of following weight portion: aluminium 98.5～99.3 parts, copper 0.3～0.4 part, silver 0.1～0.3 part, chromium 0.1～0.3 part, magnesium 0.1～0.3 part, zinc 0.1～0.2 part；

The manufacture method of a kind of enamel-covered wire described above, it is characterised in that in second step, the diameter of described inner wire is 0.7746 with the ratio of the diameter of outer conductor.

A kind of enamel-covered wire in embodiment 2 of the present invention, it is characterised in that it is fabricated by by the following method:

The manufacture method of a kind of enamel-covered wire described above, it is characterised in that in second step, the rectangular area of described inner wire is the 60% of outer conductor outer rim circular area.

The manufacture method of the present invention is simple, easily grasp, product qualified rate is high, manufacturing speed is fast.

The above-mentioned alloy enamel-covered wire that applicant uses company to produce has carried out contrast test with copper enamel-covered wire of the prior art, the alloy enamel-covered wire of a diameter of 0.56mm and the copper enamel-covered wire of a diameter of 0.51mm diameter is used to carry out testing and having carried out performance test in the wind of same model specification speeds the rotor of wheel hub, the speed model of wheel hub of wind is 14-198D-2.125, it is wound on 6 × 8 wound stator with alloy enamel-covered wire, it is wound on 8 × 8 wound stator, i.e. alloy enamel-covered wire with copper enamel-covered wire and vacates 2 rotor slot positions.Through test, the three-phase resistance of copper enamel-covered wire is respectively 258 Ω, 257 Ω, 258 Ω, alloy enamel-covered wire wound stator three-phase resistance is respectively 363 Ω, 362 Ω, 362 Ω, during 48 volts of voltage: the no-load speed of copper enamel-covered wire is 404r, peak torque is 45N m, peak efficiency is 81.5%, temperature rise Δ t=30.56K；The no-load speed of alloy enamel-covered wire is 401r, peak torque is 43N m, peak efficiency is 79.8%, temperature rise Δ t=35.26K.Above-mentioned test data show, alloy enamel-covered wire in the present invention and copper enamel-covered wire of the prior art achieve performance relatively, although data have fraction difference, but through actually used, and no abnormal, effectively instead of copper enamel-covered wire of the prior art, applicant is additionally around two dead slots, and test again around only 1/3 tankage when, data are completely superior to the data of copper enamel-covered wire.

The alloy enamel-covered wire of production is also used in the electrical equipment such as electric tool rotor, miniature motor rotor, small-sized electric automatic vehicle rotor, electromagnetic stove coil, miniature transformer by applicant, all achieves excellent equivalent effect.

Alloy enamel-covered wire cost in the present invention substantially reduces than copper enamel-covered wire of the prior art saving about 25%, weight, effectively reduces cost of transportation；Being additionally, since outer conductor is also copper, therefore the coating of enamelled coating is convenient as the coating of copper enamel-covered wire of the prior art.In the present invention, when inner wire cross section is also round shape, accordingly, the cross-sectional area of inner wire is the 55～65% of outer conductor cross section circular area to the diameter ratio of inner wire and outer conductor.Enamel-covered wire in the present invention, when 20 DEG C, resistivity has reached the optimal value of 0.0220 Ω m, and when 20 DEG C the resistivity of copper enamel-covered wire be 0.01724 Ω m, 20 DEG C time aluminium enamel-covered wire resistivity be 0.0258 Ω m, therefore, the present invention has relatively low resistivity, has preferable electric conductivity.

The present invention is not limited to above-mentioned preferred forms, it will be appreciated that the design of the present invention can be implemented to use by other various forms, and they also fall within protection scope of the present invention.

Claims

1. an enamel-covered wire, it is to be made up of inner wire, outer conductor, the enamelled coating that is coated in outside outer conductor inner wire integral coating lived；The material that it is characterized in that described outer conductor is copper, and the material of inner wire is aluminium or alloy, a diameter of d1 of inner wire, a diameter of d2 of outer conductor, enamelled coating the ratio of a diameter of d3, d1 and d2 more than or equal to 0.7416 and less than or equal to 0.8062；The difference of d3 Yu d2 is 2～20 μm；The material of described enamelled coating is to be made up of the material of following weight portion: polyamic acid 3～6 parts, mutual-phenenyl two acid bromide two alcohol ester 2～4 parts, dimethylacetylamide 58～65 parts, '-diphenylmethane diisocyanate 15～20 parts, polyethylene terephthalate 12～16 parts, poly-amino resins 3～5 parts, ethyl acetate 4～5 parts, butyl acetate 3～4 parts, mica 4～5 parts, alundum (Al2O3) 2～2.5 parts, commercially available varnish 4～6 parts, ethanol 2～5 parts.

2. an enamel-covered wire, it is to be made up of inner wire, outer conductor, the enamelled coating that is coated in outside outer conductor inner wire integral coating lived；The material that it is characterized in that described outer conductor is copper, and the material of inner wire is aluminium or alloy, and a diameter of d1 of inner wire, a diameter of d2 of outer conductor, the ratio of a diameter of d3, d1 and d2 of enamelled coating are 0.7746；The difference of d3 Yu d2 is 2～20 μm；The material of described enamelled coating is to be made up of the material of following weight portion: polyamic acid 3～6 parts, mutual-phenenyl two acid bromide two alcohol ester 2～4 parts, dimethylacetylamide 58～65 parts, '-diphenylmethane diisocyanate 15～20 parts, polyethylene terephthalate 12～16 parts, poly-amino resins 3～5 parts, ethyl acetate 4～5 parts, butyl acetate 3～4 parts, mica 4～5 parts, alundum (Al2O3) 2～2.5 parts, commercially available varnish 4～6 parts, ethanol 2～5 parts.

3. an enamel-covered wire, it is to be made up of inner wire, outer conductor, the enamelled coating that is coated in outside outer conductor inner wire integral coating lived；The material that it is characterized in that described outer conductor is copper, the material of inner wire is aluminium or alloy, the cross section of inner wire is rectangle, the cross section outer rim of outer conductor is circular, the center of inner wire coincides with the center of outer conductor, on arbitrary cross section of enamel-covered wire: the rectangular area of inner wire is the 55～65% of outer conductor outer rim circular area, the thickness of enamelled coating is 1～10 μm；When the material of described inner wire is alloy, described alloy is aluminium alloy or magnesium alloy or the alloy material being made up of following weight portion: aluminium 98.5～99.3 parts, copper 0.3～0.4 part, silver 0.1～0.3 part, chromium 0.1～0.3 part, magnesium 0.1～0.3 part, zinc 0.1～0.2 part；The material of described enamelled coating is to be made up of the material of following weight portion: polyamic acid 3～6 parts, mutual-phenenyl two acid bromide two alcohol ester 2～4 parts, dimethylacetylamide 58～65 parts, '-diphenylmethane diisocyanate 15～20 parts, polyethylene terephthalate 12～16 parts, poly-amino resins 3～5 parts, ethyl acetate 4～5 parts, butyl acetate 3～4 parts, mica 4～5 parts, alundum (Al2O3) 2～2.5 parts, commercially available varnish 4～6 parts, ethanol 2～5 parts.

4. an enamel-covered wire, it is to be made up of inner wire, outer conductor, the enamelled coating that is coated in outside outer conductor inner wire integral coating lived；The material that it is characterized in that described outer conductor is copper, and the material of inner wire is the alloy material being made up of following weight portion: aluminium 98.5～99.3 parts, copper 0.3～0.4 part, silver 0.1～0.3 part, chromium 0.1～0.3 part, magnesium 0.1～0.3 part, zinc 0.1～0.2 part；A diameter of d1 of inner wire, a diameter of d2 of outer conductor, enamelled coating the ratio of a diameter of d3, d1 and d2 more than or equal to 0.7416 and less than or equal to 0.8062；The difference of d3 Yu d2 is 2～20 μm.

5. an enamel-covered wire, it is to be made up of inner wire, outer conductor, the enamelled coating that is coated in outside outer conductor inner wire integral coating lived；The material that it is characterized in that described outer conductor is copper, and the material of inner wire is the alloy material being made up of following weight portion: aluminium 98.5～99.3 parts, copper 0.3～0.4 part, silver 0.1～0.3 part, chromium 0.1～0.3 part, magnesium 0.1～0.3 part, zinc 0.1～0.2 part；The cross section of inner wire is rectangle, the cross section outer rim of outer conductor is circular, the center of inner wire coincides with the center of outer conductor, on arbitrary cross section of enamel-covered wire: the rectangular area of inner wire is the 55～65% of outer conductor outer rim circular area, and the thickness of enamelled coating is 1～10 μm.

6. an enamel-covered wire, it is to be made up of inner wire, outer conductor, the enamelled coating that is coated in outside outer conductor inner wire integral coating lived；The material that it is characterized in that described outer conductor is copper, and the material of inner wire is alloy, a diameter of d1 of inner wire, a diameter of d2 of outer conductor, enamelled coating the ratio of a diameter of d3, d1 and d2 more than or equal to 0.7416 and less than or equal to 0.8062；The difference of d3 Yu d2 is 2～20 μm；Described alloy is aluminium alloy or magnesium alloy or almag；The material of described enamelled coating is to be made up of the material of following weight portion: polyamic acid 3～6 parts, mutual-phenenyl two acid bromide two alcohol ester 2～4 parts, dimethylacetylamide 58～65 parts, '-diphenylmethane diisocyanate 15～20 parts, polyethylene terephthalate 12～16 parts, poly-amino resins 3～5 parts, ethyl acetate 4～5 parts, butyl acetate 3～4 parts, mica 4～5 parts, alundum (Al2O3) 2～2.5 parts, commercially available varnish 4～6 parts, ethanol 2～5 parts.

7. the preparation method of an enamel-covered wire, it is characterised in that manufacture method comprises the steps of

8. the preparation method of an enamel-covered wire, it is characterised in that manufacture method comprises the steps of

The manufacture method of a kind of enamel-covered wire the most according to claim 8, it is characterised in that the rectangular area of inner wire described in second step is the 60% of outer conductor outer rim circular area.