JPH08237900A - Electric rotary machine - Google Patents

Abstract

PURPOSE: To provide an electric rotary machine which can facilitate coil winding work and cause no cost increase even with a stator cast integrally with a hous ing. CONSTITUTION: This electric rotary machine, which is manufactured by cast- forming a housing and a stator core integrally with each other by means of die casting, is provided with the stator core divided into an inner periphery where a stator winding is wound and an outer periphery 3A which constitutes a magnetic passage, whereas the outer periphery 3A is cast-formed integrally with the housing 1 by means of die casting, and the inner periphery where the stator winding is wound is inserted into the outer periphery 3A. It is possible to facilitate coil winding work without causing any fear of the housing 1 interfering with a coil insertion machine, and varnish adhering to the housing during varnishing work, thus restraining cost increase completely, making sufficient use of advantages of integral cast-forming.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary electric machine such as an induction motor, and more particularly to a rotary electric machine suitable as a general-purpose induction motor having a relatively small capacity.

[0002]

2. Description of the Related Art As a rotary electric machine such as a general-purpose induction motor having a relatively small capacity, one having a structure as shown in FIG. 5 has been generally used conventionally. In FIG. 6, reference numeral 1 denotes a housing, also called a frame or a frame, which is made of a material such as an aluminum alloy into a substantially cylindrical shape by die casting, and constitutes a casing of a rotary electric machine.

A heat radiating fin 1a is in the form of a strip extending in the axial direction, is integrally cast with the housing 1, and is formed substantially radially on the outer periphery thereof. 2A and 2B are end brackets, which are also called bearing brackets, and are provided with bearings 7A and 7B, which are attached to both ends of the housing 1 by spigot fitting.

Reference numeral 3 is a stator core, 4 is a stator coil, and the stator core 3 is made of a laminated body of silicon steel plates, and the stator coil 4 is provided in a plurality of slots provided on the inner periphery thereof. It is wound and constitutes a stator (armature) as a whole. Reference numeral 5 denotes a rotor, which has a rotary shaft 6, and the rotary shaft 6 is rotatably held by bearings 7A and 7B of the end brackets 2A and 2B, so that the rotor is fixed at a predetermined position in the stator. It is configured to rotate in opposed positions.

In such a rotary electric machine, the stator core 3 is previously inserted inside the housing 1 and attached to the inner peripheral wall of the housing 1, and then the rotor 5 is inserted in the stator 3.
, And then the bearings 7A and 7B are fitted to the rotary shaft 6 so that the end brackets 2A and 2B are fitted to both ends of the housing 1 respectively, and a plurality of bolts are attached.
By means of (not shown), the housing 1 is fixedly attached and assembled.

The rotary shaft 6 is fitted by means such as shrink fitting.
As described above, the rotor 5 is fixed, and one end side (right side in the drawing) of the rotor 5 is inserted through the bearing 7A of the end bracket 2A and protrudes to the outside to form an output shaft. And
The other end side (the same left side) is projected from the bearing 7B of the end bracket 2B, and the outer fan 8 is attached to this portion.

Reference numeral 9 denotes an end cover, which forms a cover for covering the outer fan 8. The end cover 9 is provided with an opening for taking in outside air. Therefore, when the outer fan 8 is rotated by the rotor 5, the outside air is sucked through the opening of the end cover 9, and the outside air is ventilated along the radiating fins 1a on the outer surface of the housing 1 to obtain a cooling action. It is like this.

By the way, as described above, in such a rotary electric machine, as described above, the stator core 3 is previously inserted into the housing 1 and attached to the inner peripheral wall thereof. If the adhesion between the inner peripheral surface of the housing 1 and the outer peripheral surface of the stator core 3 is poor, a sufficient cooling effect cannot be obtained.

For this reason, conventionally, a method of shrink-fitting or press-fitting the stator in the housing has been used to obtain high adhesion, but this method has a problem in workability. In addition, there is a risk that the housing may be deformed, and the number of steps is increased. Therefore, in such a rotary electric machine, when die-casting the housing, a method of casting and encapsulating the stator integrally with the housing has been proposed.

FIG. 4 shows a conventional technique by cast-in casting. In FIG. 4, (a) is a side sectional view of the upper half, and (b) is
[Fig. 4] is a front view showing four half in the length direction. As shown in the figure, in this prior art, the outer peripheral surface 3a of the stator core 3 is used as a part of a die casting mold for molding the inner surface of the housing 1, and the housing 1 and the stator core 3 are integrally formed by die casting. After that, the stator winding is wound around the stator core 3 to form a stator.

Therefore, according to this prior art, since the housing 1 and the stator core 3 are completely in close contact with each other and are integrated from the beginning, the shrink fitting process and the press-fitting process are unnecessary.

[0012]

In the above-mentioned prior art, no consideration is given to the work of winding the stator winding, and the work of inserting the coil to wind the stator winding (coil winding (Work) was difficult, and there was a problem that the cost increased. That is, in this prior art, as described above, since the housing 1 and the stator core 3 are integrally cast and molded by die casting, the stator winding is wound around the stator core 3, so Child iron core 3 is housing 1
The coil winding electric work must be performed in a state of being located at the back of the coil, which makes the work difficult and increases the cost.

It is an object of the present invention to provide a rotating electric machine in which the coil winding electric work is easy and the cost is not increased even though the stator is integrally cast with the housing.

[0014]

According to the first aspect of the present invention,
The above object is to fix a rotary electric machine having a stator inside a housing, in which at least an outer peripheral surface of the stator core is used as a part of a mold and the housing and the stator are integrally cast-molded by die casting. Using two bottomed cylindrical members as die-casting type such that the stator winding winding portion of the child core is wrapped inside, and the vicinity of the outer periphery of the side surface of the stator core is sandwiched from both sides, This allows
This is achieved by casting and molding while the armature winding is wound around the stator.

According to a second aspect of the present invention, the object is to have a stator inside the housing, and at least the outer peripheral surface of the stator core is used as a part of the mold to integrally form the housing and the stator by die casting. In a rotary electric machine that is cast-molded into, the stator core is divided into an inner peripheral portion around which the stator winding is wound and an outer peripheral portion that constitutes a magnetic path, and the outer peripheral portion of the iron core is This is achieved by integrally casting and molding by housing and die casting, and the inner peripheral portion of the iron core is inserted into the outer peripheral portion of the iron core after winding the stator winding.

[0016]

The bottomed cylindrical member according to the first aspect of the present invention functions to wrap and protect the portion of the stator on which the winding wire is applied during die casting. As a result, it is possible to perform cast-in-molding integrally with the housing by die casting, using the stator core on which the stator winding has been applied in advance.

In the stator core divided into the inner peripheral portion and the outer peripheral portion in the second aspect of the present invention, the winding work in the inner peripheral portion and the integral cast-in molding in the outer peripheral portion can be independently performed. To do so. As a result, the winding work can be performed only on the inner peripheral portion of the stator core independently of the housing.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rotary electric machine according to the present invention will be described below in detail with reference to the illustrated embodiments. FIG. 1 shows the first of the present invention.
In the figure, 10A and 10B are cylindrical members with a bottom, 4 is a stator winding, and the others are the same as in the prior art of FIG.

The bottomed cylindrical members 10A, 10B are used only during die casting, and are molds for determining the shape of the inner peripheral surface of the housing 1 other than the portion in contact with the outer peripheral surface 3a of the stator core 3. (Mold).

Usually, in die casting of a housing that does not use integral cast-in molding as in this embodiment, the mold portion that determines the shape of the inner peripheral surface of the housing 1 is simply called a columnar center core. In the embodiment of FIG. 1, a member having a cylindrical bottom is used.
That is, as shown in the figure, two bottomed cylindrical members are used, with their bottomless ends facing each other, and pressed from both sides of the stator core 3 so as to sandwich them. The stator core 3 including the child core 3 is combined with a mold (metal mold) for determining the outer shape of the housing 1 and die casting is performed, so that the stator core 3 is wrapped and integrally molded.

By the way, in such die casting using aluminum or its alloy, the surface temperature of the mold including the stator core 3 becomes a considerably high temperature, for example, about 300 ° C. As a result, the winding is preliminarily performed. If the existing stator core is integrally cast and molded as it is, the temperature of the winding becomes extremely high and the insulation performance cannot be maintained.

In the embodiment of FIG. 1, however, two bottomed cylindrical members 10 are used as the mold inside the housing 1.
Since A and 10B are used and die-casting is performed in a state in which the portion of the stator core 3 where the stator winding 4 is applied is enclosed inside these, the bottomed cylindrical member 10A, The temperature rise of the stator winding 4 can be suppressed within a desired range by, for example, sending cooling air into the inside of the 10B, and even after the stator winding 4 is applied, its insulating performance is improved. Since there is no risk of being damaged by heat, the housing 1 and the stator core 3 can be integrally cast and molded as they are.

Therefore, according to this embodiment, even when the housing 1 and the stator core 3 are integrally cast and molded,
Winding can be done in advance when the stator core is bare, so there is no concern that the housing will interfere with the coil insertion machine or that varnish will adhere to the housing during varnish work. Since the electric work can be performed easily, the advantage of the integral cast-in molding, that is, the close contact between the housing and the stator core can be completely obtained, and the advantage that high cooling performance can be provided by good heat dissipation And since it has been integrated from the beginning,
The advantage that the shrinking process and the press-fitting process are not required and the manufacturing process can be simplified can be fully utilized, and the cost increase can be further suppressed sufficiently.

Next, a second embodiment of the present invention will be described with reference to FIGS. In these figures, 3A is the outer peripheral part of the stator core, 3B is the inner peripheral part of the stator core, and in FIG. 3, the inner peripheral part 3B is shown fitted inside the outer peripheral part 3A. These are laminated bodies of electromagnetic steel sheets, each of which is made independently. Therefore, in this embodiment, these are combined to form the stator core 3, and the other structure is the same as that of the prior art shown in FIG.

The outer peripheral portion 3A is a magnetic path portion of the stator core 3,
On the inner peripheral surface thereof, as shown in the drawing, a plurality of concave grooves 3As extending in the axial direction and arranged in parallel in the circumferential direction are formed. Then, this outer peripheral portion 3A uses the outer peripheral surface 3a as a part of a die casting mold for molding the inner surface of the housing 1 as in the prior art of FIG. It is supposed to be molded.

The inner peripheral portion 3B is a portion around which the stator winding 4 (not shown) of the stator core 3 is wound, and therefore, the inner peripheral surface thereof has a tooth portion as shown in the drawing. (Teeth portion) 3Bt and slot portion 3Bs are formed, and teeth are formed on the outer peripheral surface thereof so as to mesh with the concave grooves 3As formed on the inner peripheral surface of the outer peripheral portion 3A.

In this embodiment, as shown in FIG. 2, only the outer peripheral portion 3A is integrally cast-molded with the housing 1 by die casting. On the other hand, the inner peripheral portion 3B is the outer peripheral portion 3A.
Separated from the above, the coil winding electric work is independently performed to wind the stator winding.

After that, by fitting the inner peripheral portion 3B around which the stator winding is wound inside the outer peripheral portion 3A which is integrally cast and molded with the housing 1, the housing of the induction motor is mounted. And the stator will be completed.

Therefore, in the second embodiment, since only the outer peripheral portion 3A of the stator core 3 is integrally cast and molded with the housing 1, there is no particular problem even if it is exposed to a high temperature during die casting. Therefore, it is integrated from the beginning with the advantage of the integral cast-in molding, that is, the close contact between the housing and the stator core can be completely obtained, and high cooling performance due to good heat dissipation can be provided. Therefore, it is possible to make full use of the advantage that the shrinking process and the press-fitting process are not necessary and the manufacturing process can be simplified.

Further, according to the second embodiment, since only the inner peripheral portion 3B can be taken out and the winding can be independently applied, the housing interferes with the coil inserting machine, and the housing is used during varnishing. There is no concern that varnish will adhere to the coil, and the coil winding electrical work can be performed easily.

Further, according to the second embodiment, since the stator core 3 is divided into the outer peripheral portion 3A and the inner peripheral portion 3B,
The weight of the iron core handled during die casting work or coil winding electric work is lightened, and as a result, even an electric motor with a considerably large capacity can be easily assembled and manufactured.

[0032]

According to the first aspect of the present invention, it is possible to integrally cast and form the housing and the housing by die casting using the stator core which has been wound with the stator in advance. There is no need to worry about interference with the inserter or varnish sticking to the housing during varnish work, and coil winding electrical work can be performed easily, resulting in complete contact between the housing and the stator core. Since it can be obtained, high cooling performance due to good heat dissipation can be provided, and since it is integrated from the beginning, shrink fitting process and press-fitting process are not required, and the manufacturing process can be simplified. It is possible to reliably suppress the cost increase while fully utilizing the advantages of the package molding.

According to the second aspect of the present invention, the winding work at the inner peripheral portion of the stator core and the cast-in molding at the outer peripheral portion can be independently performed, so that the winding work can be performed at the housing. Irrespective of the above, it can be separately performed only on the inner peripheral portion of the stator core, and therefore, there is no concern that the housing will interfere with the coil inserting machine or that the varnish will adhere to the housing during varnish work. The coil winding electric work can be easily performed, and as a result, the cost can be surely suppressed while the advantages of the integral cast-in molding are fully utilized.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing a first embodiment of a rotating electric machine according to the present invention.

FIG. 2 is a partial sectional view showing a second embodiment of the rotating electric machine according to the present invention.

FIG. 3 is a partially enlarged sectional view showing a second embodiment of the rotating electric machine according to the present invention.

FIG. 4 is a partial cross-sectional view showing a conventional example of a rotating electric machine.

FIG. 5 is a partial cross-sectional side view showing an example of a rotary electric machine to which the present invention is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 1a Cooling fin 3 Stator core 3A Stator core outer peripheral part 3B Stator core inner peripheral part 3a Peripheral surface 4 Stator winding 6 Blower casing 7, 8 Spider 9 Fixed shaft 10 Armature (stator) 11 Is rotor 12, 13 rotor bracket 14, 15 bearing 16 centrifugal blade blade 16a shroud 17 axial flow blade blade 18 power supply connection terminal part

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Toshimitsu Oku 7-1, 1-1 Higashi Narashino, Narashino City, Chiba Prefecture Hitachi Industrial Co., Ltd. Industrial Equipment Division (72) Inventor Akihiro Sekine 7-1 Higashi Narashino, Narashino City, Chiba Prefecture Issue Hitachi Industrial Co., Ltd. Industrial Equipment Division (72) Inventor Keiichiro Kaishin 7-11 Higashi Narashino, Narashino, Chiba Prefecture Industrial Equipment Division Hitachi, Ltd. (72) Eiichiro Sugawa 7-1, Higashi Narashino, Narashino, Chiba Prefecture No. 1 Industrial Equipment Division, Hitachi, Ltd. (72) Inventor Yoshitoshi Ishikawa 7-1, Higashi Narashino, Narashino City, Chiba Prefecture Industrial Equipment Division, Hitachi, Ltd. (72) Takashi Watanabe Higashi Narashino, Narashino City, Chiba Prefecture 7-1-1 No. 1 Industrial Equipment Division, Hitachi, Ltd.

Claims (2)

[Claims] 1. A rotating electric machine having a stator inside a housing, wherein the housing and the stator are integrally cast-molded by die casting, with at least the outer peripheral surface of the stator core as a part of a mold. The two die-cast bottomed cylindrical members are arranged so as to wrap the stator winding winding portion of the stator core inside and sandwich the outer peripheral portion of the side surface of the stator core from both sides. A rotating electric machine manufactured by cast molding in a state where an armature winding is wound around the stator by using as a mold. 2. A rotating electric machine having a stator inside a housing, wherein at least the outer peripheral surface of the stator core is used as a part of a mold to integrally cast and mold the housing and the stator by die casting. In, the iron core of the stator is divided into an inner peripheral portion around which the stator winding is wound and an outer peripheral portion forming a magnetic path, and the outer peripheral portion of the iron core is integrally formed with the housing by die casting. An electric blower, wherein the inner peripheral portion of the iron core is inserted into the outer peripheral portion of the iron core after winding the stator winding.