WO2013132786A1

WO2013132786A1 - Method for separating windings of electric motor

Info

Publication number: WO2013132786A1
Application number: PCT/JP2013/001150
Authority: WO
Inventors: 渡辺　彰彦; 篤史高野; 武彦長谷川; 畑矢　英児; 裕午劉; 近藤　憲司
Original assignee: パナソニック株式会社
Priority date: 2012-03-06
Filing date: 2013-02-27
Publication date: 2013-09-12
Also published as: JP2013187926A; CN104067490B; CN104067490A; JP5903580B2

Abstract

This method for separating windings of an electric motor is a method for separating an insulating film on an end part of a winding that is wound on a magnetic pole of a stator. This winding-separation method is characterized in that a winding end part is pulled into a tensioned state, and an insulating-film-separating device having a rotating cutting blade is moved, separating the insulating film. It is thereby possible to separate the insulating film without breaking the wire. Even if aluminum, which is weaker than copper wire or iron wire, is employed in a conductor of a winding, it will be possible to prevent breakage when the insulating film is being separated.

Description

Winding peeling method of electric motor

The present invention relates to a technique in which an insulating coating at the tip of an insulating coating-coated electric wire whose core wire is covered with at least one layer of insulating coating is peeled off so that the core wire is exposed and joined to other components by soldering. In particular, the present invention relates to a method for peeling a winding wound around a stator or the like of an electric motor.

So far, copper wire has been mainly selected as the conductor of electric wires used in motors (electric motors). However, the use of electric wires using conductors other than copper has been increasing due to recent soaring copper wires and improvements to the weight reduction of motors.

Since electric wires other than copper wires, such as aluminum wires, have a strong aluminum oxide layer on their surfaces, soldering connections with terminals and lead wires are extremely difficult unless the insulating coating and the aluminum oxide layer are removed. It was difficult. In addition, since the strength of the aluminum wire is smaller than that of the copper wire, there has been a problem that many disconnections occur when the insulating coating and the aluminum oxide layer are peeled off while rotating the cutting blade.

Therefore, in order to deal with such problems, a technique for removing an oxide film by ultrasonic waves (for example, see Patent Document 1) and a technique for preventing or removing oxidation using a reducing gas (for example, a patent) Document 2), a technique for joining by using ultrasonic waves and zinc-based solder together (for example, see Patent Document 3), a technique for peeling an insulating film in a flux (for example, see Patent Document 4), and the like have been proposed. .

However, the removal of the aluminum oxide layer as described in the patent literature is an important issue, but since no measures have been taken for disconnection or insulation coating residue at the time of the insulation coating peeling of the electric wire in the previous process, Deterioration of the defective rate during the production of electric motors and deterioration of soldering quality have been issues. Especially for thin wires, it was a big problem.

JP-A-2-54947 JP 2004-323977 A Japanese Patent Laid-Open No. 9-239531 JP 2009-148053 A

The present invention solves the above-described conventional problems, does not require large-scale equipment, can increase the reliability of joining with other components at low cost, and can be insulated without breaking the wires. Provided is an insulating film peeling method for an insulating coated electric wire capable of peeling a film.

The winding separation method of the electric motor of the present invention is a method of peeling off the insulating coating at the winding end of the winding wound around the magnetic pole of the stator, and the tension is applied by pulling the winding end. The insulating coating is peeled off by moving the insulating coating peeling device in which the cutting blade rotates.

This makes it possible to peel off the insulating film without disconnecting the electric wire. In other words, by rotating a plurality of cutting blades to cut the insulating film, it can be peeled uniformly and in a short time, and by applying tension to the end of the winding and peeling, preventing disconnection Can do. And, by applying tension, it corrects the distortion and bending of the electric wire and prevents the electric wire from sagging when it is peeled off by the cutting blade. And disconnection can be prevented.

FIG. 1 is a partial cross-sectional view of an electric motor according to an embodiment of the present invention. FIG. 2 is a configuration diagram of a stator of the electric motor. FIG. 3 is a cross-sectional view of the electric wire according to the embodiment of the present invention. FIG. 4 is an explanatory diagram of the winding peeling method according to the embodiment of the present invention.

(Embodiment)
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a structural diagram showing a partial cross section of an electric motor according to an embodiment of the present invention. FIG. 2 is a view showing a specific configuration example of a finished winding product (finished stator product) 17 of the same motor. In the present embodiment, an example of an electric motor that is mounted for an air conditioner as an electric device and that is a brushless motor for driving a blower fan will be described. In the present embodiment, an example of soldering connection between a wire conductor and a terminal will be described. The finished winding product 17 shown in FIG. 2 is configured using a winding in which the insulating coating at the tip of the insulating coating-coated electric wire is peeled off by the winding peeling method of the electric motor of the present invention, as shown in FIG. The electric motor is provided with such a wound product 17.

In FIG. 1 and FIG. 2, a stator 13 is configured by molding a stator core 1 around which a winding 3 is wound with an insulating resin 7 which is a molding material for integrally molding the mold. . An insulator 2 that insulates the stator core 1 is interposed between the stator core 1 and the winding 3. Further, the winding start line or the winding end line (hereinafter referred to as the winding end 4) is peeled off the insulating coating, applied with soldering flux, and soldered to the terminals 6.

The rotor 12 is inserted inside the stator 13 through a gap. The rotor 12 includes a disk-shaped rotating body 11 including the rotor core 8 and a shaft 10 to which the rotating body 11 is fastened so as to penetrate the center of the rotating body 11. The rotor core 8 holds a plurality of permanent magnets 9 in the circumferential direction facing the inner peripheral side of the stator 13. Two bearings 14 that support the shaft 10 are attached to the shaft 10 of the rotor 12. One of the two bearings 14 is fixed to an insulating resin 7 that is integrally molded with the mold, and the other is fixed to a metal bracket 15. Further, the brushless motor incorporates a printed circuit board 16 on which a drive circuit is mounted. After this printed circuit board 16 is electrically joined to the terminal 6, the bracket 15 is press-fitted into the stator 13 to form a brushless motor.

FIG. 3 is a cross-sectional view of the electric wire 20 used as the winding 3. Here, the electric wire 20 may have a configuration in which the conductor 18 is covered with the insulating coating 19, and the insulating coating 19 may have a configuration in which the conductor 18 is covered with one or two layers of insulating coating. Furthermore, the structure covered with the multilayer insulation film of three or more layers may be sufficient. When the insulating coating 19 is a multilayer, the withstand voltage can be improved, which is advantageous for further miniaturization. Moreover, as the electric wire 20, although the conductor 18 is covered with the at least 1 layer of insulating film 19, the oxide film produced | generated by the manufacturing process of an electric wire, for example, an aluminum oxide layer exists in the conductor surface.

In the present embodiment, as the electric wire 20, an aluminum conductor 18 made of metal is coated with a two-layer insulating coating 19 made of polyester and nylon (so-called PEWN electric wire) is used. An example will be described. However, it is not restricted to this electric wire 20, You may use what is comprised with another material. The material of the insulating coating 19 may be any of urethane, polyester, and polyimide.

FIG. 4 is an explanatory diagram of a winding peeling method according to the embodiment of the present invention. In FIG. 4, the winding end 4 is enlarged and shown in comparison with the finished winding product 17. The insulating film peeling device 108 includes a cutting blade 101, a cutting blade rotating device 102, a cutting blade moving device 103, and a tension applying device 104. The cutting blade 101 has a plurality of blades, and peels off the insulating coating 19 on the winding end 4 attached to the inside of the blade by cutting. The cutting blade rotating device 102 rotates the cutting blade 101 in the circumferential direction of the winding end 4. The cutting blade moving device 103 moves the cutting blade 101 in the extending direction of the winding end 4. Then, the tension applying device 104 applies tension to the winding end 4 mounted in the insulating coating film peeling device 108 in the direction of the extended end of the winding end 4.

First, the winding end 4 is passed through the centers of the three cutting blades 101, the cutting blade rotating device 102, and the cutting blade moving device 103, and the tip 4 a of the winding end 4 is connected to the tension applying device 104. Then, tension is applied by the tension applying device 104 to pull the electric wire 20 with a force of 5 MPa or more and 50 MPa or less with respect to the electric wire 20 (more specifically, the conductor 18 of the electric wire 20) in the tension applying direction indicated by an arrow 109. To do. Here, the insulating film peeling device 108 is disposed outside the finished winding product 17 so that the winding end 4 extends in the radial direction of the finished winding product 17.

Next, the cutting blade 101 is rotated by the cutting blade rotating device 102, the cutting blade moving device 103 is moved in the direction of the arrow 105 which is the same direction as the tension application direction, and the insulating coating 19 is peeled off. And the conductor part 4b after peeling an insulating film is processed.

At this time, the conductor 18 of the electric wire 20 preferably has a diameter of 0.15 mm or more and 0.5 mm or less. The insulating coating 19 has a thickness of approximately 0.01 mm to 0.03 mm. Further, when the insulating coating 19 is peeled off, it is preferable that the conductor 18 is peeled from the surface at a depth of 0.001 mm or more and 0.005 mm or less at the same time to form the conductor portion 4b after peeling off the insulating coating. That is, the insulating coating 19 is first peeled off from the winding end 4 of the electric wire 20 by cutting with the cutting blade 101, and this cutting is continued to a little deeper so that the surface of the conductor 18 is also peeled off. It is preferable to scrape the thickness of 0.001 mm to 0.005 mm on the 18 surface. Thereby, the aluminum oxide layer on the aluminum surface which is the conductor 18 can also be removed. Further, the cutting blade 101 is structured to bite into the electric wire 20 when rotated, and the amount of peeling can be adjusted by adjusting the biting stopper.

Next, the portion where the insulating film 19 remains (the portion that has not been peeled off) is cut in the vicinity of the tip portion 4a of the winding end portion 4. Next, a flux is applied to the conductor portion 4b after the insulating film is peeled off, soldered to the terminal 6, and molded with the insulating resin 7, whereby the stator 13 is configured. In this embodiment, a flux with a solid content of 15%, a viscosity of 4 mPa, a halogen content of 0.08 ± 0.02% is used, and the solder is Sn-3Ag-0.5Cu. did. Next, the rotor 12, the printed circuit board 16, and the bracket 15 were assembled into an electric motor.

(Example 1)
In the content described in the embodiment, the electric wire 20 was used in which the conductor material was aluminum, the conductor diameter was 0.3 mm, the insulating coating 19 was PEWN, and the insulation film thickness was 0.012 mm. Further, a tension of 30 MPa was applied to the conductor of the electric wire in the direction of applying a tension applied to the winding end 4, the cutting blade 101 was rotated at a rotational speed of 1500 r / min, and the insulating coating 19 was peeled off. At this time, the direction 105 in which the cutting blade moves was the same as the tension application direction. Further, the biting prevention stopper of the cutting blade 101 was adjusted so that the conductor 18 was simultaneously peeled by a depth of 0.002 mm. Production of 1000 electric motors was carried out under such conditions, and the disconnection failure rate at the time of insulation coating peeling, the insulation coating remaining failure rate after peeling, and the soldering connection failure rate with the terminals 6 were confirmed.

(Comparative Example 1)
For comparison with the first embodiment, as a conventional insulating film peeling method, the winding end 4 is passed through the center of the three cutting blades 101, the cutting blade 101 is rotated by the cutting blade rotating device 102, and the cutting blade is cut. It moves with the moving apparatus 103, the insulating film 19 is peeled, and the conductor part 4b after peeling an insulating film is processed. Also in this comparative example, the electric wire 20 was used in which the conductor material was aluminum, the conductor diameter was 0.3 mm, the insulating coating 19 was made of PEWN, and the insulation film thickness was 0.012 mm.

Further, the rotational speed of the cutting blade 101 was 1500 r / min, and the biting prevention stopper of the cutting blade 101 was adjusted so that the conductor 18 was peeled off at a depth of 0.002 mm at the same time. Production of 1000 electric motors was carried out under such conditions, and the disconnection failure rate at the time of insulation coating peeling, the insulation coating remaining failure rate after peeling, and the soldering connection failure rate with the terminals 6 were confirmed.

Table 1 shows the results of confirmation between Example 1 and Comparative Example 1.

As can be seen from Table 1, when the method of the present invention is used, the insulating coating 19 can be peeled without breaking even with a thin aluminum wire having a conductor diameter of 0.3 mm. Furthermore, since the aluminum oxide layer produced | generated on the conductor surface can also be removed simultaneously, the soldering connection with the terminal 6 can also be implemented easily. By applying tension, this corrects the distortion and bending of the wire, and prevents the wire from sagging when it is peeled off by the cutting blade, thereby preventing uneven cutting of the cutting blade into the wire. Because it is.

In general, the aluminum oxide layer is said to be 0.0005 mm or less. By peeling off the aluminum oxide layer at the same time as peeling off the insulating film 19, soldering with the terminal 6 while improving the productivity is achieved. Wiring defects can be reduced.

On the other hand, in the method of Comparative Example 1, the tip end side of the winding end 4 moves simultaneously with the rotation of the cutting blade 101, or looseness or sagging occurs, making it difficult for the cutting blade to bite in uniformly, resulting in disconnection. Insulation film remains after peeling, and since aluminum oxide cannot be removed, a problem occurs in the soldering connection with the terminal 6.

Therefore, according to the winding peeling method for an electric motor of the present invention, it is possible to provide an insulating film peeling method for an electric wire that can increase the reliability of joining to other components at low cost while improving productivity.

As described above, the present invention is a method for peeling off the insulating film at the winding end of the winding wound around the magnetic pole of the stator, and the tension is applied by pulling the winding end. The winding film peeling method is characterized in that the insulating film is peeled off by moving an insulating film peeling device in which the cutting blade rotates. Thereby, an insulating film can be peeled without disconnecting an electric wire. Even when aluminum having a strength lower than that of a copper wire or an iron wire is adopted as a conductor of the winding, disconnection when the insulating coating is peeled can be prevented.

Also, if the moving direction of the insulating film peeling device is the same as the direction in which the tension is applied, it is possible to easily prevent the sagging of the electric wire that occurs when peeling with the cutting blade.

Also, the tension is desirably 5 MPa or more and 50 MPa or less with respect to the conductor. If the pressure is less than 5 MPa, it is not possible to correct the distortion or bending of the electric wire or to prevent the electric wire from sagging when it is peeled off by the cutting blade. In addition, the electric wire may be disconnected at a tension greater than 50 MPa.

Also, it is desirable that the winding conductor has a diameter of 0.15 mm or more and 0.5 mm or less. If the thickness is less than 0.15 mm, the insulation film is peeled off when the insulating blade is peeled off due to the rotation of the cutting blade, and if the wire is larger than 0.5 mm, the distortion of the wire due to the tension or the bending wrinkle cannot be corrected.

Also, when stripping the insulation film of the winding, it is desirable to strip the conductor of the winding at the same time from 0.001 mm to 0.005 mm. When the conductor part of the winding is peeled off at less than 0.001 mm, the aluminum oxide layer is not completely removed, so that the soldering connection between the conductor part and the terminal or the lead wire cannot be easily performed. Moreover, when the conductor part of a coil | winding is simultaneously peeled larger than 0.005 mm, the amount of biting of a cutting blade may become large and may cause a disconnection.

In addition, when peeling the conductor part of a coil | winding larger than 0.005 mm simultaneously, it is more preferable to carry out by dividing the frequency | count of peeling into multiple times.

As described above, the winding separation method for an electric motor of the present invention can be applied to an electric motor such as an air conditioner, and can also be applied to other electric motors.

DESCRIPTION OF SYMBOLS 1 Stator iron core 2 Insulator 3 Winding 4 Winding end part 4a Tip part (of winding end part) 4b Conductor part (after peeling) 6 Terminal 7 Insulating resin 10 Shaft 12 Rotor 13 Stator 16 Printed circuit board 17 Finished winding product 18 Conductor 19 Insulating coating 20 Electric wire 101 Cutting blade 102 Cutting blade rotating device 103 Cutting blade moving device 104 Tension applying device 108 Insulating coating peeling device

Claims

A method for peeling off an insulating film at a winding end of a winding wound around a magnetic pole of a stator, wherein the winding end is pulled to be in a tensioned state, and the insulating coating is peeled off when a cutting blade rotates. A method for peeling a winding of an electric motor, wherein the insulating coating is peeled off by moving an apparatus.
2. The method according to claim 1, wherein the conductor of the winding is aluminum.
The method for peeling a winding of an electric motor according to claim 1 or 2, wherein the moving direction of the insulating film peeling device is the same as the direction in which the tension is applied.
4. The method according to claim 1, wherein the tension is 5 MPa or more and 50 MPa or less with respect to the winding. 5.
5. The method according to claim 1, wherein a diameter of the conductor of the winding is 0.15 mm or more and 0.5 or less.
6. The electric motor according to claim 1, wherein when the insulating film of the winding is peeled off, the conductor of the winding is peeled off simultaneously at 0.001 mm or more and 0.005 mm or less. Winding peeling method.