JP2000152574A - Induction motor and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce manhour necessary for manufacture of an induction motor, realize miniaturization and weight reduction of constitution, and improve reliability. SOLUTION: A motor 31 is equipped with rotating magnetic substance 55 wherein different magnetic poles are alternately magnetized along the peripheral direction, and a cage rotor 40 which is arranged surrounding externally the rotating magnetic substance 55. It is rotatably fixed to a rotating shaft 41 via bearings 43 and 44 on one side and the other side, respectively, in the axial line direction of the shaft 41. The cage rotor 40 is fixed to the rotating shaft 41 via frame ring 53 on the one side in the axial line direction, and supports the magnetic substance 55 rotatably via a bearing 56 on the other side in the axial line direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction motor.

[0002]

2. Description of the Related Art FIG. 7 is a cross-sectional view of a typical prior art induction motor (hereinafter referred to as a motor) 1 with a built-in rotating magnetic body.
FIG. 8 is a front view of the rotating magnetic body 25 used in the motor 1, and FIG. 9 is a sectional view of the rotating magnetic body 25. Hereinafter, the configuration of the conventional motor 1 will be described with reference to FIGS. The motor 1 includes a stator iron core (hereinafter, iron core) 2
And a stator 4 in which a coil 3 is wound. The stator 4 is housed in a frame 5. Bearing housings 6 and 7 integrally connected to the frame 5 by rivets 12 are disposed near both ends in the axial direction of the stator 4, and bearings 8 and 9 are fitted to the bearing housings 6 and 7. Fixed,
A metal rotating shaft 11 coaxially mounted on the cage rotor 10 is rotatably supported.

The cage rotor 10 includes a cylindrical body 15 made of a non-magnetized magnetic material and rotatably connected to the rotary shaft 11 via bearings 13 and 14, and a cylindrical body 15.
A magnetic cylindrical body 16 magnetized alternately with different magnetic poles along the circumferential direction on the surface of the rotor, a rotor iron core 17 fixed to the rotating shaft 11, and copper and aluminum mounted on the rotor iron core 17. A plurality of bars 18 having a shape such as a rod made of a conductive material such as, for example, end rings 19 and 20 fixed to both ends of each bar 18, and fixed to the end rings 19 and 20 with bolts 21 and 22, Iron core 17, bar 18,
Frame rings 23 and 24 for fixing the end rings 19 and 20 to the rotating shaft 11 are provided. The cylindrical body 15 and the magnetic cylindrical body 16 constitute a rotating magnetic body 25.

[0004] As shown in FIGS. 8 and 9, the cylindrical body 15 of the rotary magnetic body 25 protrudes from both ends of the cylindrical part 26 to which the magnetic cylindrical body 16 is fixed, and both ends in the axial direction of the cylindrical part 26. Protrusions 2 in which bearings 13 and 14 are respectively stored
7, 28. The outer ends of the bearings 13 and 14 and the ends of the protrusions 27 and 28 are arranged so as to be flush with each other.

[0005] The motor 1 having such a rotating magnetic body 25 is used when the cage rotor 10 is mounted on the rotating shaft 11.
Since the end rings 19 and 20 need to be fixed to the frame rings 23 and 24 fixed to the rotating shaft 11, they are assembled in the following procedure.

First, a rotating magnetic body 25 is inserted from the non-load side into the rotating shaft 11 on which the bearing 13 is mounted in advance.
Thereafter, the bearing 14 is inserted from the non-load side to freely support the rotating magnetic body 11 and
3 is attached to the rotating shaft 11. Next, the frame ring 24 is attached to the end ring 20 of the cage rotor 10 opposite to the frame ring 23 with bolts 22, the cage rotor 10 is mounted on the rotating shaft 11, and the end ring 19 is attached to the corresponding frame ring. 23 is fixed with bolts 21.

[0007]

In such a motor 1, each frame ring 23, 24 is connected to each end ring 1
The work of individually assembling the components 9 and 20 is required, and the production is troublesome.

In addition, it is necessary to screw a plurality of bolts 21 on each of the frame rings 23 and 24, which increases the number of manufacturing steps and the number of parts. Further, the bolts 21 may be loosened during use of the motor 1, and the rotating squirrel cage rotor 10 may be disassembled and the motor 1 may be damaged, resulting in a problem in reliability.

Further, since the frame rings 23 and 24 are mounted on both sides of the cage rotor 10 in the axial direction, the length of the cage rotor 10 in the axial direction becomes longer and the motor 1 becomes larger. There is. In addition, a cage rotor 1
0 increases the moment of inertia of the squirrel cage rotor 10, increasing the difficulty in controlling the rotational speed of the motor 1 and reducing the operational reliability.

As described above, the rotating magnetic body 25 has protrusions 27 and 28 for accommodating the bearings 13 and 14, respectively.
Are formed to protrude from the cylindrical portion 26. Therefore, there is a problem that the weight of the cage rotor 10 increases. Also,
Since the protruding portions 27 and 28 are formed so as to protrude from the cylindrical portion 26, the frame rings 23 and 24 mounted on the rotating magnetic body 25 in the axial direction protrude outward in the axial direction. There is a problem that the length increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to reduce the labor required for manufacturing, to reduce the size and weight of the configuration, and to improve the reliability of the induction motor. And a method for producing the same.

[0012]

In the induction motor according to the present invention, different magnetic poles are alternately magnetized in the circumferential direction, and are rotated by bearings on one side and the other side in the axial direction of the rotating shaft. A rotating magnetic body rotatably mounted on the shaft, and provided around the rotating magnetic body, fixed to the rotating shaft via a mounting member on one axial side, and via a bearing on the other axial side. A cage rotor for rotatably supporting the rotating magnetic body.

According to a second aspect of the present invention, in the induction motor of the first aspect, the attachment member has a structure in which an end ring and a frame ring of a cage rotor are integrated.

According to a third aspect of the present invention, there is provided the induction motor according to the first aspect, wherein the rotary magnetic body has a storage recess for storing the bearing disposed between the rotary shaft and one side in the axial direction. The axially one end of the bearing and the rotating magnetic body housed in the housing recess is arranged flush with each other.

According to a fourth aspect of the present invention, there is provided a method of manufacturing an induction motor, comprising: a rotating magnetic body having different magnetic poles alternately arranged along a circumferential direction and having a bearing provided radially outward on one axial side; A first step of fixing to the rotating shaft via a radially inner bearing on one side and the other side in the direction;
A cage rotor with a mounting member attached to the other side in the axial direction,
A second step of attaching the rotating magnetic body to the rotating shaft to which the rotating magnetic body is attached.

[0016]

In the induction motor according to claim 1, the squirrel-cage rotor is fixed to the rotating shaft via a mounting member on one side in the axial direction, and the rotating magnetic body is rotatable via a bearing on the other side in the axial direction. I support it. The rotating magnetic body is rotatably attached to the rotating shaft via bearings on one side and the other side in the axial direction.

Accordingly, when a mounting tool such as a bolt is used when mounting a mounting member such as a frame ring to an end ring of a cage rotor, the number of mounting tools to be used and the number of mounting steps are significantly reduced. can do.

Further, since the mounting member such as the frame ring is mounted on the end ring of the cage rotor using only one side in the axial direction of the cage rotor by using such bolts or the like, both ends in the axial direction are required. As compared with the case where the induction motor is mounted, the risk that the bolt is loosened during use of the induction motor and the induction motor is damaged can be reduced.

Further, as described above, the attachment member such as the frame ring may be attached to the end ring of the cage rotor only on one side in the axial direction of the cage rotor.
Compared to a case where mounting members such as frame rings are mounted on both sides of the cage rotor in the axial direction, the length of the cage rotor in the axial direction can be reduced, and the size of the induction motor can be reduced. For the same reason, the weight of the squirrel-cage rotor, and hence the moment of inertia, can be reduced, the control of the rotational speed of the induction motor can be facilitated, and the operational reliability of the induction motor can be improved. can do.

In the induction motor according to the second aspect, the mounting member has a configuration in which an end ring and a frame ring of a cage rotor are integrated. This eliminates the need for a connecting tool such as a bolt for connecting the end ring and the frame ring in addition to the operation and effect according to the first aspect, and the connecting tool is loosened and dropped during operation of the induction motor to induce the induction. It is possible to prevent problems such as damage to the electric motor. In addition, the work of connecting the end ring and the frame ring by the connecting tool becomes unnecessary, and the number of manufacturing steps is remarkably reduced.

In the induction motor according to claim 3, the rotary magnetic body is provided with a storage recess for housing the bearing disposed between the rotating magnetic body and one side in the axial direction, and the storage recess is formed in the storage recess. Ends of the accommodated bearing and the rotating magnetic body on one side in the axial direction are flush with each other. Therefore, in addition to the functions and effects according to the first aspect, the axial end portion of the rotating magnetic body and the bearing are prevented from protruding in the axial direction, and the overall length, weight and moment of inertia of the cage rotor in the axial direction are reduced. As described above, the operational reliability of the induction motor can be improved.

Since the method for manufacturing an induction motor according to the fourth aspect includes the steps as described above, the mounting member may be mounted on only one side of the cage rotor in the axial direction. Thereby, the labor required for manufacturing can be remarkably reduced as compared with the case where the cage rotor is mounted on both sides in the axial direction.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a first embodiment of the present invention. FIG. 1 is a sectional view of an induction motor (hereinafter, motor) 31 of the present embodiment, and FIG. FIG. 3 is a front view of the body 55 viewed from the axial direction, and FIG. 3 is a sectional view of the rotating magnetic body 55.

Referring now to FIG. 1, the overall configuration of the motor 31 of the present embodiment will be described. The motor 31 has a stator 34 in which a coil 33 is wound around a stator iron core (hereinafter, iron core) 32, and the stator 34 is housed in a frame 35. At both ends in the axial direction of the stator 34, bearing housings 36 and 37 integrally connected to the frame 35 with rivets 42 are arranged.
Bearings 38, 39 are fitted and fixed to 37, and a rotating shaft 4 having a diameter D 1 coaxially mounted on a cage rotor 40.
1 is rotatably supported. The cage rotor 40 is
A rotating body 45 made of a non-magnetized magnetic material and rotatably connected to the rotating shaft 41 via bearings 43 and 44, and alternately attached to different magnetic poles along the circumferential direction on the surface of the rotating body 45. The magnetized magnetic cylinder 46 and the rotating shaft 41
A rotor core 47 that is rotatably supported by a bearing 56 at a right end portion in FIG. 1 along the axial direction and that is rotatably supported by a bearing 56, and copper mounted on the rotor core 47, A plurality of bars 48 having a rod-like shape made of a conductive material such as aluminum, end rings 49 and 50 fixed to both ends of each bar 48, and a bolt attached to the end ring 49 on the left side of the bar 48 in FIG. Rotor core 4 fixed at 51
7, a bar ring 48, and an end ring 49 are provided on the left side of the bar 48 in FIG. The frame ring 53 is fixed to the rotating shaft 41 using a key or the like. The rotating body 45 and the magnetic cylinder 46 constitute a rotating magnetic body 55.

A fixing pipe 61 for positioning and fixing the bearing 39 is provided between the bearings 44 and 39 of the rotating shaft 41.
A C-shaped retaining ring 62 for fixing the bearing 56 is provided near the right end of the rotating body 45 in FIG.

Hereinafter, FIG. 2 and FIG. 3 will be referred to together. The rotating body 45 is formed of a non-magnetized magnetic material, is continuous with the inner peripheral portion 60 having an inner diameter D2 larger than the diameter D1 of the rotating shaft 41 and an outer diameter D4, and both sides of the inner peripheral portion 60 in the axial direction. , 44 in which the inner diameter D3 is stored (D3> D2)
, And a cylindrical portion 59 having an axial length L3. The axial lengths L1 and L2 of the storage portions 57 and 58 are such that the bearings 43 and 44 are stored therein, and the axial ends of the storage portions 57 and 58 and the axial ends of the bearings 43 and 44 are respectively provided. They are chosen to be flush.
In addition, the axial length L2 of the circumferential lug 58 is different from that of the bearing 4 with respect to the axial end of the storage portion 58 for mounting the bearing 56.
4 may be chosen so that the axial end is depressed.
Further, the C-shaped retaining ring 62 is provided on the outer periphery of the storage portion 58.
A groove 52 is formed in which is fitted.

As shown in FIG. 2, the magnetic cylinder 46 has six magnetic pole regions in which N poles and S poles are alternately magnetized along the circumferential direction. The method of forming such a magnetic pole region is based on six magnetic plates N magnetized on the N pole or the S pole.
This is realized by fixing the first, S1, N2, S2, N3, and S3 to the rotating body 45 along the circumferential direction with an adhesive so that the magnetic poles are alternated.

Further, the motor 31 of the present embodiment having the above-described configuration is manufactured roughly according to the following manufacturing procedure.

That is, in the first step, a bearing 56 is mounted on the outside of the storage portion 58 of the rotary magnetic body 55 by a C-shaped retaining ring 62, and the rotary magnetic body 55 is mounted on the rotary shaft 41 on which the bearing 43 is mounted in advance. The bearing 44 is inserted into the rotating shaft 41 from the non-load side, and is freely supported on the rotating shaft 41.

In a second step, the cage rotor 40 to which the frame ring 53 is fixed is attached to the rotating shaft 41 on which the rotating magnetic body 55 is mounted. Thus, the motor 3
1 is assembled.

In the motor 31 of this embodiment, the cage rotor 40 is fixed to the rotating shaft 41 via the frame ring 53 on the left side of FIG. Is fixed to the rotating shaft 41 in the radial direction via a bearing 56, a housing portion 58 of the rotating body 45, and the bearing 44 on the right side. The rotating magnetic body 55 is fixed to the rotating shaft 41 via bearings 43 and 44 and a fixing pipe 61 along the axial direction.

Accordingly, the number of components and the number of steps for mounting the bolts 51 used when mounting the frame ring 53 to the cage rotor 40 can be greatly reduced.

Since the frame ring 53 is mounted on the cage rotor 40 using only the bolts 51 or the like on only one axial side of the cage rotor 40, the frame ring 53 is mounted on both axial sides. Compared to the case of the prior art,
The risk of the motor 31 being damaged due to the loosening of the bolt 51 during use of the motor 31 can be reduced.

Further, as described above, the frame ring 5
3 is attached to the cage rotor 40 by the cage rotor 4
Since only one side in the axial direction of 0 is required, the cage rotor 40
The length of the cage rotor 40 in the axial direction can be reduced, and the size of the motor 31 can be reduced, as compared with the case of the related art in which the frame rings 53 are mounted on both sides in the axial direction. For the same reason, the weight of the squirrel-cage rotor 40, and hence the moment of inertia thereof, can be reduced, and the control of the rotation speed of the motor 31 can be facilitated. Can be improved.

Further, since the motor 31 of this embodiment is manufactured by the above-described procedure, the frame ring 53
May be mounted on only one side of the cage rotor 40 in the axial direction. As a result, the time and effort required for manufacturing can be significantly reduced as compared with the case of the related art in which the cage rotor 40 is mounted on both sides in the axial direction.

Hereinafter, another embodiment of the present invention will be described with reference to FIGS. 4 is a sectional view of the motor 31a of the present embodiment, FIG. 5 is a front view of the rotating magnetic body 55a provided in the motor 31a as viewed from the axial direction, and FIG. 6 is a sectional view of the rotating magnetic body 55a. . This embodiment is similar to the previous embodiment, and corresponding parts are denoted by the same reference numerals.
The feature of the present embodiment is that, as shown in FIGS. 4 and 6, the rotating magnetic body 55a of the present embodiment has a shape in which the axial length L1 of the rotating magnetic body 55 in the above embodiment is removed. That is. Still another feature of the present embodiment is that the end ring 49a of the present embodiment is replaced with the end ring 49 of the above embodiment.
Instead, the hole diameter is reduced by an amount corresponding to the removal of the axial length L1 described above, and the frame ring 53 is also used. At this time, similarly to the frame ring 53 in the above-described embodiment, the end ring 49a is configured to be fixable to the rotating shaft 41 using, for example, a key. Thus, in this embodiment, the frame ring 53 in the above embodiment is not employed. Still another feature of this embodiment is that the rotating body 45, the magnetic cylindrical body 46, and the bearing 4
3 in FIG. 4 are formed flush with each other.

The motor 31a of this embodiment is manufactured as follows.

That is, in the first step, a bearing 56 is mounted on the outside of the storage portion 58 of the rotary magnetic body 55a by a C-shaped retaining ring 62, and the rotary magnetic body 55a is mounted on the rotary shaft 41 on which the bearing 43 is mounted in advance. The bearing 44 is inserted into the rotating shaft 41 from the non-load side, and is freely supported on the rotating shaft 41.

In the second step, the end rings 49a,
The cage-shaped rotor 40a, which is fixed to both ends of the plurality of bars 48 in the axial direction by welding or the like, is attached to the rotating shaft 41 on which the rotating magnetic body 55a is mounted. Thus, the motor 31a is assembled. Thus, in the motor 31a of this embodiment, in addition to the functions and effects described in the above embodiment, a connecting tool such as the bolt 51 for connecting the end ring 49 and the frame ring 53 as in the above embodiment is unnecessary. Therefore, it is possible to prevent the occurrence of problems such as the coupling tool becoming loose and falling off during the operation of the motor 31a and damaging the motor 31a. Also, the operation of connecting the end ring and the frame ring by the connecting tool is not required, and the number of manufacturing steps is significantly reduced.

The present invention is not limited to the above embodiment, but includes a wide variety of modifications without departing from the spirit of the present invention.

[0041]

As described above, in the induction motor according to the first aspect, the squirrel-cage rotor is fixed to the rotating shaft via the mounting member on one side in the axial direction, and the bearing on the other side in the axial direction. The rotating magnetic body is rotatably supported. Further, the rotating magnetic body is rotatably mounted on the rotating shaft via bearings on one side and the other side in the axial direction.

Accordingly, when a mounting tool such as a bolt is used when mounting the mounting member to the cage rotor, the number of mounting tools to be used and the number of mounting steps can be greatly reduced.

Further, since the mounting member is mounted on the cage rotor using such bolts only on one side in the axial direction of the cage rotor, it is compared with the case where the mounting member is mounted on both sides in the axial direction. In addition, the risk of damage to the induction motor due to loosening of bolts during use of the induction motor can be reduced.

Further, as described above, the mounting members need only be mounted on the cage rotor on one side in the axial direction of the cage rotor. Therefore, the mounting members are mounted on both axial sides of the cage rotor. In comparison with the case where the squirrel-cage rotor is used, the axial length of the squirrel-cage rotor can be shortened, and the induction motor can be downsized. For the same reason, the weight of the squirrel-cage rotor, and hence the moment of inertia, can be reduced, the control of the rotational speed of the induction motor can be facilitated, and the operational reliability of the induction motor can be improved. can do.

In the induction motor according to the second aspect, the mounting member has a configuration in which the end ring and the frame ring of the cage rotor are integrated. This eliminates the need for a connecting tool such as a bolt for connecting the end ring and the frame ring in addition to the operation and effect according to the first aspect, and the connecting tool is loosened and dropped during operation of the induction motor to induce the induction. It is possible to prevent problems such as damage to the electric motor. In addition, the work of connecting the end ring and the frame ring by the connecting tool becomes unnecessary, and the number of manufacturing steps is remarkably reduced.

According to a third aspect of the present invention, in the induction motor, the rotating magnetic body has a storage recess for housing the bearing disposed between the rotating shaft and the one side in the axial direction, and is housed in the storage recess. The ends of the bearing and the rotating magnetic body on one side in the axial direction are arranged flush with each other. Therefore, in addition to the functions and effects according to the first aspect, the axial end portion of the rotating magnetic body and the bearing are prevented from protruding in the axial direction, and the overall length, weight and moment of inertia of the cage rotor in the axial direction are reduced. As described above, the operational reliability of the induction motor can be improved.

Since the method for manufacturing an induction motor according to the fourth aspect includes the steps as described above, the mounting member may be mounted on only one side of the cage rotor in the axial direction. Thereby, the labor required for manufacturing can be remarkably reduced as compared with the case where the cage rotor is mounted on both sides in the axial direction.

[Brief description of the drawings]

FIG. 1 is a sectional view of a motor 31 according to a first embodiment of the present invention.

FIG. 2 is a front view of a rotating magnetic body 55 provided in the motor 31 as viewed from an axial direction.

FIG. 3 is a cross-sectional view of the rotating magnetic body 55.

FIG. 4 is a sectional view of a motor 31a according to a second embodiment of the present invention.

FIG. 5 is a front view of a rotating magnetic body 55a provided in the motor 31a as viewed from an axial direction.

FIG. 6 is a sectional view of a rotating magnetic body 55a.

FIG. 7 is a cross-sectional view of a conventional motor 1.

FIG. 8 is a front view of the rotating magnetic body 25 provided in the motor 1 as viewed from the axial direction.

FIG. 9 is a cross-sectional view of the rotating magnetic body 25.

[Explanation of symbols]

 31, 31a Motor 38, 39, 43, 44, 56 Bearing 40, 40a Cage-shaped rotor 45 Rotating body 46 Magnetic cylinder 47 Rotor iron core 49, 49a, 50 End ring 53 Frame ring 55, 55a Rotating magnetic body 61 Fixing pipe 62 C type retaining ring

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H02K 21/14 H02K 21/14 MF term (reference) 5H013 LL00 NN00 PP01 PP03 5H615 AA01 BB01 BB06 BB07 BB14 PP02 PP25 SS09 SS19 SS20 5H621 BB02 GA01 JK01 5H622 CA02 CA10 PP03 PP19

Claims (4)

[Claims] A rotating magnetic body which is alternately magnetized along a circumferential direction, and is rotatably mounted on the rotating shaft via bearings on one side and the other side in the axial direction of the rotating shaft; A cage provided around the rotary magnetic body, fixed to the rotary shaft via a mounting member on one axial side, and rotatably supporting the rotary magnetic body via a bearing on the other axial side; An induction motor in which a rotor is arranged. 2. The mounting member according to claim 1, wherein the end ring and the frame ring of the cage rotor are integrated.
2. The induction motor according to claim 1. 3. The rotating magnetic body is provided with a storage recess for housing the bearing disposed between the rotating shaft on one side in the axial direction and the bearing housed in the storage recess. 2. The induction motor according to claim 1, wherein an end of the magnetic material on one side in the axial direction is arranged flush with the magnetic material. 3. 4. A rotating magnetic body having different magnetic poles alternately magnetized along the circumferential direction and having a bearing provided radially outward on one side in the axial direction, and radially inward on one side and the other side in the axial direction. First fixed to the rotating shaft via the bearing of
A method of manufacturing an induction motor, comprising: a step of mounting a cage rotor having a mounting member mounted on one side in the axial direction to the rotary shaft to which the rotating magnetic body is mounted.