JPS63316656A - Squirrel-cage induction flat motor - Google Patents

Abstract

PURPOSE:To obtain a small-sized and lightweight squirrel-cage induction flat motor, by concentrating the flux generated by a drive winding to a central ring segment pole, internal and external ring poles and a ring segment. CONSTITUTION:A squirrel-cage flat motor 10 is composed of a ring-shaped stator 12 made of high permeability material such as soft iron or solid amorphous metal, etc., a squirrel-cage disc rotor 14 and a cover 15. The ring-shaped stator 12 is equipped with three-phase drive windings 22-24, an internal ring pole 26, an external ring pole 28 and a central ring segment pole 30. A ring- shaped space 32 is formed between the internal ring pole 26 and the central ring segment 30. A ring-shaped space 34 is formed between the external ring pole 28 and the central ring segment 30. The drive windings 22-24 are provided in the ring-shaped spaces 32 and 34 different in their radii of curvature. The rears of the internal ring pole 26, external ring pole 28 and central ring segment pole are magnetically connected with a ring stator yoke 36.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] The present invention relates to squirrel cage induction motors, and more particularly to squirrel cage induction flat motors.

〔Technical field〕

BACKGROUND ART With the recent progress in making various industrial equipment smaller, lighter, and more sophisticated, there is a demand for small, high-performance induction motors. In conventional squirrel-cage induction motors, the stator and squirrel-cage rotor form a closed-loop magnetic circuit in a plane perpendicular to the axial direction, so the magnetic flux passes through the stator in the circumferential direction and through one of the outer circumferences of the rotor. The field structure is such that the magnetic field passes through the other side of the outer circumference of the rotor and flows into the stator again via an air gap. For this reason, the length of the magnetic path inevitably increases, magnetic resistance increases, and efficiency deteriorates. This tendency becomes more pronounced as the capacity of the induction motor increases, as the stator and rotor become larger. Furthermore, due to the special structure of the stator in general induction motors, it is not possible to improve the space factor of the drive windings, and it is difficult to achieve higher efficiency and make them smaller and thinner. Ta.

To solve this problem, a flat motor called a print motor has been proposed. This print motor is a DC motor, and a large number of permanent magnets are arranged on the plane of the stator so that N and S poles alternate, and a disc rotor equipped with armature windings is opposed to the permanent magnets. The structure is such that drive current is supplied to the armature winding via the commutator and brush. A disadvantage of this type of flat motor is that the presence of magnetic coils or armature windings in the magnetic circuit between the rotor and the stator yoke necessarily results in a large air gap and a high magnetic reluctance. Furthermore, the target magnetic field of each coil or armature winding is dispersed, the target magnetic field area of these coils or windings becomes large, and there is a drawback that the magnetic flux density for the same magnetic pole is low. As a result, the magnetic field becomes weak and the efficiency of the motor deteriorates, making it difficult to further reduce the size, weight, and performance of the motor. Furthermore, print motors have mechanical sliding and wear parts, making them unreliable and requiring periodic maintenance and inspection.In addition, print motors generate sparks and noise, which severely limits the environmental conditions in which they can be used. 1) There was also a limit to the overload capacity in the high-speed range due to mechanical rectification. Therefore, this motor is not suitable for high-speed rotation, cannot be used in locations with environmental conditions such as vibration, shock, and high temperature, and furthermore, has the disadvantage that the characteristics of the motor deteriorate due to aging. Moreover, although various industries have been eagerly awaiting the emergence of squirrel cage induction flat motors that can be driven with alternating current voltage, they have not yet been realized.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a highly reliable squirrel cage induction flat motor that is highly efficient, compact, lightweight, and highly efficient.

Another object of the present invention is to provide a squirrel cage induction flat motor that can be made ultra-thin.

Another object of the present invention is to provide a highly efficient, small and lightweight squirrel cage induction flat motor by narrowing the target magnetic field area of the drive winding and increasing the magnetic flux density for the same magnetic pole to strengthen the magnetic field. .

Another object of the invention is to eliminate mechanical sliding and wear parts;
The object of the present invention is to provide a highly reliable squirrel cage induction flat motor that does not require maintenance or inspection.

Another object of the present invention is to provide a squirrel-cage induction flat motor that is suitable for high-speed rotation, has a large overload capacity, and is resistant to environmental conditions such as vibration, shock, and high temperatures.

Another object of the present invention is to provide a low-cost squirrel-cage induction flat motor that has a simple structure, is easy to work with one winding and is easy to assemble, and is practical for small to large capacity machines.

[Structure of the invention]

The squirrel cage induction motor of the present invention includes a first annular segment magnetic pole formed of segments circumferentially divided by a plurality of slots and extending in the axial direction; a second annular magnetic pole extending in the direction; and a second annular magnetic pole disposed surrounding the segment; The second annular magnetic pole is energized to form a closed loop magnetic circuit in a plane parallel to the axial direction, thereby greatly reducing the length of the magnetic circuit, and the cage-shaped disk is connected to the first and second annular magnetic poles via an air gap. It is characterized by having rotors facing each other.

〔Example〕

A preferred embodiment of the squirrel cage induction flat motor according to the present invention will be described with reference to FIG. In FIG. 1, a squirrel cage induction flat motor 10 includes an annular stator 12 made of a high permeability material such as soft iron or solid amorphous metal, a squirrel cage disc rotor 14, and a cover 15. The annular stator 12 rotatably supports the protruding shaft 2° of the rotor 14 via bearings 16,18.

The bearing 16 is held in place by a bearing holder 13 fixed to the stator 12 by screws 15. First to third phase drive windings 22, 23, and 24 are arranged on the annular stator 12.

The annular stator 12 includes an inner annular pole 26 , an outer annular pole 28 , and a central annular segment pole 30 . An annular space 32 is formed between the inner annular pole 26 and the central annular segment pole 30, while an annular space 34 is formed between the outer annular pole 28 and the central annular segment pole 30. The drive windings 22, 23, 24 are arranged in annular slots 32, 34 with different radii of curvature. Internal annular magnetic pole 26. Outer annular magnetic pole 28. and the rear part of the central annular segment magnetic pole are magnetically coupled by an annular stator yoke 36.

As is clear from FIG. 2, the central annular segment magnetic pole 3
0 includes a plurality of segments or arcuate magnetic poles 30a formed at regular intervals in the circumferential direction, and radial slots 30b formed between these magnetic poles. 1st to 3rd phase drive winding 22
．． 23 and 24 are arranged in the annular slot 32 and 34 and the radial slot 30b so that the phase is shifted by 1206 in electrical angle. That is, in FIG. 2, the three-phase motor 10 has 12 slots 30b and 12 segment magnetic poles 30a.
Each drive winding is arranged to surround three segment magnetic poles to form a four-pole structure. Drive winding 22,2
An example of a specific connection of 3.24 is shown in FIG.

As mentioned above, in FIG.
．． 24 each surround three segments 30a and are arranged in a quadrupole configuration. Drive winding 22, 23.2
4 are connected to a 3φ AC power source through input terminals R, S, and T, respectively, and when the 3φ AC power is supplied, the magnetic poles of each group are excited to become N and S poles. When so energized, the magnetic flux φ passes from the central annular segment pole 30 through the squirrel cage disc rotor 14 into the inner annular pole 26 and the outer annular pole 28, and from there via the annular stator yoke 36 and back again. It enters the central annular segment magnetic pole 3o to form a closed loop (see Figures 1 and 2).

In FIGS. 1 and 4, the squirrel-cage disc rotor 14 includes a rotor disc 4o made of a conductive material such as stainless steel, copper, or aluminum. The rotor disk 40 is fixed with screws 44 to a collar 42 which is press-fitted into the small diameter portion 20a of the rotating shaft 20 or fixed by a key (not shown) or other suitable means. On the same plane of the rotor disk 40, first and second annular horn-shaped rotors 46, 48 having different radii of curvature are concentrically supported by screws 50, 52, respectively.

The first annular squirrel cage rotor 46 has a squirrel cage winding having a rotor bar 54 and an end ring 56 connected to the rotor disk 40, and an annular iron core made of a high magnetic permeability material such as a laminated steel plate such as silicon steel or a solid amorphous metal. 58. The second annular squirrel cage rotor 48 has a rotor disk 40
It comprises a squirrel cage winding with a rotor bar 60 and an end ring 62 connected to the rotor bar 60 and an annular core 64 made of a highly permeable material.

As is clear from FIG. 1, the first annular squirrel cage rotor 46
The inner and outer peripheries of the inner annular magnetic pole 26 and the central annular segment magnetic pole 30 respectively face each other via an air gap. Similarly, the inner circumference and outer circumference of the second annular squirrel cage rotor 48 are connected to the central annular segment magnetic pole 3 through a gap, respectively.
0 and the outer annular magnetic pole 28.

In the above configuration, when the drive windings 22, 23, and 24 are connected to a three-phase AC power source via the input terminals R, S, and T, a rotating magnetic field is generated in the annular stator 12 and the squirrel-cage disc rotor 1
Secondary induced currents are generated in the squirrel cage windings of the four annular squirrel cage rotors 46 and 48, respectively, and the rotor 14 rotates continuously. At this time, the magnetic flux φ enters the annular core 58.64 from the central annular segment magnetic pole 30 in FIG.
From there respectively inner annular poles 26. Outer annular magnetic pole 28
through the stator yoke 36 and return to the central annular segment magnetic pole 30. At this time, the rotor bar 54.60 simultaneously cuts the magnetic flux φ, producing an eddy current in the direction determined by Fleming's right-hand rule, and as a result, an electromagnetic force is generated in the rotor bar 54.60 according to Fleming's left-hand rule. The squirrel cage disc rotor 14 rotates in a predetermined direction.

FIG. 5 shows a second embodiment of the squirrel cage induction flat motor 10 according to the present invention, and FIG. 6 shows a plan view of the squirrel cage disc rotor 14' of FIG. Use signs.

In Figure 5.6, the squirrel cage disc rotor 14' is a high permeability flat rotor fixed to the collar 42 with screws 44.
A disk 70 and a squirrel cage winding 72 are provided. The squirrel cage winding 72 has a conductive inner ring 74 . The outer ring 76, the first and second intermediate rings 78, 80, and the inner shaft 74. Outer ring 76, first
, second intermediate ring 78. and a plurality of radial conductor bars 82 connected to the QO. In this configuration, when the magnetic flux φ passes from the central annular magnetic pole 30 to the inner and outer annular magnetic poles 26 and 28, a secondary current is induced in the squirrel cage winding 72 of the squirrel cage disc rotor 14', causing the rotor 14' to rotate. Rotate in the direction of the magnetic field.

The rest is the same as the irMth embodiment, so detailed explanation will be omitted.

Although the above embodiment has been described as being suitable for a three-phase AC squirrel-cage induction flat motor, the squirrel-cage induction flat motor of the present invention can also be applied to a single-phase AC motor by rotating the drive windings by 90 degrees. In addition to the flat motor, the central annular segment magnetic pole 30 and the internal and external annular magnetic poles 2
It goes without saying that 6.28 may be extended into a cylindrical shape to form a cylindrical motor.

〔effect〕

As is clear from the above, in the squirrel cage induction flat motor of the present invention, the magnetic flux generated by the drive winding is concentrated on the central annular segment magnetic pole, the inner annular magnetic pole, the outer annular magnetic pole, and the annular stator yoke, and the drive winding By narrowing the target magnetic field region, the magnetic flux density for the same magnetic pole can be significantly increased, and the effective magnetic flux density acting on the rotor can be significantly increased. Moreover, the closed-loop magnetic circuit is formed in a plane parallel to the motor axis, shortening the magnetic circuit length.
Magnetic resistance can be significantly reduced. These two advantages make it possible to improve the efficiency and performance of the squirrel cage induction motor. As a result, the squirrel cage induction motor was made smaller and lighter.
You can take shape. Furthermore, since three sides of the cross section of the drive winding of each phase are surrounded by an annular stator that is a good thermal conductor and has high magnetic permeability, the heat conduction area of the drive winding increases significantly and heat dissipation from the winding is improved. It is extremely efficient and the overload capacity of the motor is significantly increased. Moreover, since the drive winding is surrounded on all four sides by the annular magnetic poles and the annular squirrel cage rotor, it effectively prevents magnetic leakage to the outside and does not cause noise or other effects on peripheral devices. .

Since the structures of the stator, rotor, and drive winding are extremely simplified, processing, winding operations, and assembly are much easier than in the past, and a low-cost squirrel-cage induction flat motor can therefore be provided.

The squirrel-cage induction flat motor of the present invention has a simple structure and is strong, so it is suitable for high-speed, large-output applications, can withstand frequent acceleration/deceleration operations, has excellent high-temperature and low-temperature environmental performance, and has excellent operating performance during continuous use. It has great practical effects, such as no deterioration and long life.

[Brief explanation of the drawing]

1 is a partial sectional view of a three-phase squirrel cage induction flat motor according to a preferred embodiment of the present invention, and FIG. 2 is a line A-A in FIG. 1.
3 is a diagram showing the specific connection of the drive winding in FIG. 1, FIG. 4 is a plan view of the squirrel cage disc rotor in FIG. 1, and FIG. A second embodiment of the squirrel cage induction flat motor according to the invention, FIG. 6 shows a plan view of the squirrel cage disc rotor of FIG. 5, respectively. 12......Annular stator 14.14'......Squirrel cage disc rotor 2
2 to 24... Drive winding 20...
...Rotating shaft patent applicant Hi-tech Research Institute Co., Ltd. Bottom 1 Figure - Collection 2 Figure 3 ob 2/) Qin 4 concave, 5 concave

Claims (1)

[Scope of Claims] 1. A first annular segment magnetic pole composed of a plurality of segments circumferentially divided by a plurality of slots and extending in the axial direction, and formed on the same plane as the first annular segment magnetic pole, and an annular stator including a second annular magnetic pole extending in the axial direction and a plurality of drive windings arranged to surround the segment and exciting the first and second annular magnetic poles;
A squirrel-cage induction motor comprising a squirrel-cage disc rotor that faces the first and second annular magnetic poles of the annular stator with an air gap therebetween. 2. The squirrel cage induction motor according to claim 1, wherein the annular stator includes an annular stator yoke integral with the first and second annular magnetic poles. 3. Claim 1 or 2, characterized in that the squirrel cage disc rotor includes an annular squirrel cage rotor.
Squirrel cage induction motor as described in section. 4. The squirrel cage induction motor according to claim 3, wherein the inner and outer peripheries of the annular squirrel cage rotor face the first and second annular magnetic poles, respectively, with an air gap therebetween. . 5. an inner annular magnetic pole, a central annular segment magnetic pole composed of a plurality of segments circumferentially divided by a plurality of slots, and an outer annular magnetic pole formed on the same plane as the inner annular magnetic pole and the central annular segment magnetic pole; an annular stator having a plurality of drive windings arranged to surround the segment and energize the central annular segment magnetic pole and the inner and outer annular magnetic poles; and a squirrel cage facing the annular stator via an air gap. A squirrel cage induction motor consisting of a disc rotor. 6. The annular stator comprises an annular stator yoke integral with the inner and outer annular stators and the central annular segment pole.
Squirrel cage induction motor as described in section. 7. A first annular squirrel cage rotor in which the squirrel cage disc rotor faces the inner annular magnetic pole and the central annular segment magnetic pole with an air gap therebetween; and an air gap between the outer annular magnetic pole and the central annular segment magnetic pole. 7. The squirrel-cage induction motor according to claim 5, further comprising a second annular squirrel-cage rotor facing therebetween. 8. An annular stator comprising an internal annular magnetic pole arranged concentrically, a central annular magnetic pole consisting of segmented magnetic poles of a plurality of groups of poles, and an external annular magnetic pole, and segmented magnetic poles of the plurality of poles of the annular stator. a drive winding arranged to surround the plurality of poles and simultaneously exciting the plurality of groups of poles in the circumferential direction by an AC power supply; 1. A squirrel cage induction flat motor comprising a squirrel cage disc rotor with first and second annular squirrel cage rotors energized simultaneously by a plurality of groups of poles.