JPH10127018A - Manufacture of stator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a stator which can prevent the cracks of a stator core of a motor and allows the stator to have an annealing effect and have a high reliability. SOLUTION: Nearly I-shaped teeth 3a are formed at equal interval from a yoke section of a stator core and nearly U-shaped teeth 3b which is symmetrical about the center of the nearly I-shaped teeth 3a is formed from the base of every other nearly I-shaped teeth 3a. Both inside and outside every nearly U-shaped teeth 3b, inner recesses 4a and outer recesses 4b are formed. The stator core except for at least the ends of the teeth is covered with resin by insert molding (insert molding process) and a wire is wound (wire winding process) around the stator core. After winding the wire, the stator core is impregnated with heat resistant varnish (varnish treatment process) and then is heated and dried (heating and drying process).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a stator, and more particularly, to a method and a process for forming a groove insulating layer and an end plate.

[0002]

2. Description of the Related Art Conventionally, as a method of manufacturing a stator in an electric motor, as shown in FIG. 2, as an example, substantially I-shaped teeth 3a are provided at equal intervals from a yoke 2 of a stator core 1, and the substantially I A substantially U-shaped tooth portion 3b is provided symmetrically on both sides from every other base end of the U-shaped tooth portion 3a, and an inner groove 4a and an outer groove 4a are provided inside and outside the substantially U-shaped tooth portion 3b, respectively. A groove 4b is formed, and except for at least the tip of the tooth portion, insert molding with resin is performed so as to cover the stator core 1. As shown in FIGS. Layer 5
And the end plate 6 are integrally formed. Then, as shown in FIG. 5, an outer winding 8 and an inner winding 9 are wound around the stator core. FIG. 7 shows this step, but in this case, no varnish treatment was performed thereafter.

[0003] Therefore, there is no annealing effect of the molded article,
There is a problem that stress is generated due to thermal expansion / contraction and the like, stress is concentrated at a corner or the like which is a boundary between the groove insulating layer 5 and the end plate 6, cracks are generated, and dielectric breakdown is caused. I was

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and it is intended to prevent cracks at corners of a resin molded portion of a stator core of an electric motor, to provide an annealing effect and to provide insulation breakdown. It is an object of the present invention to provide a method for manufacturing a stator in which the reliability is improved and the reliability is improved.

[0005]

In order to achieve the above object, a plurality of teeth protruding from a yoke of a stator core are provided, and grooves are formed between the teeth, and at least a tip of the teeth is formed. Except for, in a stator manufacturing method in which the stator core is covered by insert molding with a thermoplastic resin and a winding is wound around the stator core, after winding the winding, impregnating with a varnish, and heating and drying. Let it be.

[0006] The heating and drying temperature of the varnish is set to 1
It should be higher than 00 ° C.

Further, the conditions for heating and drying the varnish are as follows:
Approximately 1 hour between 30 ° C and 150 ° C.

On the other hand, the varnish is a solvent-type electrically insulating varnish. The electrical insulating varnish is a polyester varnish.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A plurality of teeth protruding from a yoke of a stator core are provided, grooves are formed between the teeth, and insert molding is performed with a thermoplastic resin except at least the tips of the teeth. In the method for manufacturing a stator in which the stator core is covered and a winding is wound around the stator core, the winding is wound, and then varnish is impregnated and dried by heating.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to the accompanying drawings. Here, the same reference numerals are used for the same parts as in the related art.

FIG. 1 is a block diagram showing the steps of one embodiment of a method for manufacturing a stator according to the present invention, FIG. 2 is a plan view of a stator core used in the present invention, and FIG. 3 is insert molding according to the present invention. FIG. 4 is an enlarged plan view of a main part showing a stator core formed with a groove insulating layer and an end plate in a process, FIG. 4 is an enlarged cross-sectional view of a main part corresponding to CC ′ in FIG. 3, and FIG. FIG. 6 is a plan view showing a state after the winding step, and FIG. 6 is a plan view showing a state after the varnish processing step of the stator of the present invention.

In this embodiment, the yoke 2 of the stator core 1
, Substantially I-shaped teeth 3a are provided at equal intervals, and symmetrical substantially U-shaped teeth 3b are provided on both sides from the base end of every other of the substantially I-shaped teeth 3a. An inner groove 4a and an outer groove 4b are formed on the inside and outside of the V-shaped tooth portion 3b, respectively. The present invention is not limited to this stator core 1.

First, an insert molding process for the groove insulating layer and the end plate is performed. This will be described with reference to FIGS. Here, the groove insulating layer 5 and the end plate 6 are insert-molded using PBT (polybutylene terephthalate) which is a thermoplastic resin.

Next, a winding step will be described with reference to FIG. An outer winding 8 is wound between the outer groove 4b of the stator core 1 and the next outer groove 4b. Similarly, an inner winding 9 is wound between the inner groove 4a of the stator core 1 and the next inner groove 4a.

Further, since the varnish treatment step is performed,
This will be described with reference to FIG. In this step, the stator core 1 is impregnated with a polyester varnish of a heat-resistant varnish 7 which is a solvent type or a non-solvent type E or higher electrical insulating varnish except for at least the tips of the teeth.

Thereafter, a heating and drying step is started. Here, heat drying is performed at a temperature higher than 100 ° C., and moisture contained in the resin or the like is removed as water vapor. Further, the heating condition of the varnish 7 was set to 130 ° C.
If the temperature is set at about 1 hour between the temperature of about 150 ° C. and the temperature of about 150 ° C., an annealing effect can be obtained.

By manufacturing the stator as shown in FIG. 1 in this manner, even if stress is generated due to the thermal expansion and contraction or the like, the corner portion serving as the boundary between the groove insulating layer and the end plate is formed by the varnish. The annealing effect can be provided by the heating and drying step after the treatment.

[0018]

As described above, according to the present invention, a plurality of teeth protruding from the yoke of the stator core are provided, grooves are formed between the teeth, and at least the tip of the teeth is removed. In a method for manufacturing a stator, in which the stator core is covered by insert molding with a thermoplastic resin and a winding is wound around the stator core, after winding the winding, varnish is impregnated and dried by heating. I did it.

As a result, it is possible to provide a method for manufacturing a stator in which cracks at corners of the stator core of the electric motor can be prevented, an annealing effect can be provided, and reliability is improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing steps of one embodiment of a method for manufacturing a stator according to the present invention.

FIG. 2 is a plan view of a conventional stator core used in the present invention.

FIG. 3 is a main part enlarged plan view showing a stator core in which a groove insulating layer and an end plate are formed in an insert forming step according to the related art and the present invention.

FIG. 4 is an enlarged sectional view of a principal part corresponding to CC ′ in FIG. 3;

FIG. 5 is a plan view showing a conventional state and a state after a winding step of a stator of the present invention.

FIG. 6 is a plan view showing a stator after a varnish processing step of the present invention.

FIG. 7 is a block diagram showing steps of an example of a conventional stator manufacturing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stator core 2 Yoke part 3a Substantially I-shaped tooth part 3b Substantially U-shaped tooth part 4a Inner groove 4b Outer groove 5 Groove insulating layer 6 End plate 7 Varnish 8 Outer winding 9 Inner winding

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yuji Kawai 1116 Suenaga, Takatsu-ku, Kawasaki City Inside Fujitsu General Co., Ltd. (72) Inventor Yuji Soma 1116 Suenaga, Takatsu-ku Kawasaki City Inside Fujitsu General Co., Ltd.

Claims (5)

[Claims] A plurality of teeth protruding from a yoke of a stator core are provided, grooves are formed between the teeth, and insert molding is performed with a thermoplastic resin except for at least the tips of the teeth. A method for manufacturing a stator, comprising covering a stator core and winding a winding around the stator core, wherein after winding the winding, a varnish is impregnated and dried by heating. Method. 2. The varnish is heated and dried at a temperature of 100 ° C.
2. The method for manufacturing a stator according to claim 1, wherein the height is higher than C. 3. The condition for heating and drying the varnish is 130 °
2. The method according to claim 1, wherein the heating is performed for about 1 hour between C and 150 ° C. 4. The method according to claim 1, wherein the varnish is a solvent-type electrically insulating varnish. 5. The method according to claim 4, wherein the electrically insulating varnish is a polyester varnish.