JP2003088020A - Squirrel-cage rotor, manufacturing method therefor, and induction synchronous motor using the squirrel-cage rotor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a squirrel-cage rotor which allows reduction in manufacturing cost and the enhancement of each of assembly. SOLUTION: The squirrel-cage rotor comprises a rotor core which incorporates magnets in gaps between a squirrel-cage core and a shaft core in the axial direction; a plurality of conductors respectively inserted into grooves of the rotor core; and an end ring. The squirrel-cage core and the shaft core are integrally joined with each other by fastening portions formed in the gaps.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cage rotor, a method for manufacturing the cage rotor, and an induction synchronous motor using the cage rotor. More specifically, the present invention relates to a cage rotor capable of reducing manufacturing cost and improving assemblability, a manufacturing method thereof, and an induction synchronous motor using the cage rotor.

[0002]

2. Description of the Related Art Conventionally, a built-in magnet type induction synchronous motor, which is an electric motor having the features of both a magnet type synchronous motor and an induction motor, has been developed. For example, as shown in FIG. 3, there is an induction synchronous motor with a built-in magnet in which the magnet 108 (108a to 108d) is embedded in the cage rotor 102. In this electric motor, a stator 101 has a plurality of teeth 104 and a yoke portion 103 that connects the roots of the teeth 104, and has a substantially cylindrical shape. A three-phase winding 106 is provided on the plurality of conductor grooves 105 formed between the plurality of teeth 104. The basket-shaped rotor 102 includes a basket-shaped core 102a of a core having a basket-shaped winding and a shaft core 102b of a core attached to a shaft 107.
And has a substantially cylindrical shape that is substantially coaxial. This basket-shaped rotor 10
2 is supported by a plurality of conductors 111 that are inserted into the conductor grooves 110, and the substantially cylindrical magnet 108 is embedded in the four magnet burying holes that penetrate axially, so that the stator 101 It has four rotor magnetic poles facing the inner peripheral surface. The magnet 108 is magnetized into an N pole and an S pole as shown. The conductor 111 is made of a conductor such as copper or aluminum, and a resistance causes a difference in track characteristics, as in a general induction motor. The basket-shaped rotor 102 has a rotor magnetic pole whose rotor magnetic pole is formed by a rotating magnetic field formed by a current flowing through the stator winding 106.
It rotates by attracting or repelling the rotating magnetic pole formed by the winding 01.

[0003]

However, in the induction synchronous motor described above, since the cage core and the shaft core are separated, the structure of the core punching die becomes complicated. For example,
In the case of the continuous type, the basket-shaped iron core and the shaft iron core are separately punched and two take-out stages are required. Further, at the time of assembling, the magnet must be attached by being regulated by a jig or the like so that the outer diameter of the magnet becomes an accurate dimension.

That is, in the rotor core of the conventional induction synchronous motor, the cage core and the shaft core are separated by the space for inserting the magnet. However, there is a problem that the cost is increased in manufacturing and the assembling work of the basket type core and the shaft core is difficult.

In view of the above circumstances, the present invention provides a cage rotor capable of reducing the manufacturing cost and improving the assemblability, a method of manufacturing the cage rotor, and an induction synchronous motor using the cage rotor. The purpose is to

[0006]

The basket type rotor of the present invention comprises:
A basket including a rotor core in which a magnet is axially built in a space between a basket-shaped core and a shaft core, a plurality of conductors inserted into respective conductor grooves of the rotor core, and an end ring. A shaped rotor, characterized in that the basket-shaped iron core and the shaft iron core are integrally connected by a connecting iron portion formed in a void portion.

Further, according to the method of manufacturing the basket-shaped rotor of the present invention, the rotor core having the magnet axially incorporated in the space between the basket-shaped core and the shaft core and the conductor grooves of the rotor core. A method of manufacturing a basket-shaped rotor consisting of a plurality of conductors inserted into the core and an end ring, the step of punching a thin-walled steel plate to integrally form the cage core and the shaft core And a step of stacking the integrally formed cage core and shaft core material
A step of previously inserting a non-magnetic jig corresponding to the magnet into the magnet insertion portion in the gap between the basket-shaped iron core and the shaft iron magnet, and the jig is pushed out by the magnet. And a step of inserting a magnet.

Further, the induction synchronous motor of the present invention is characterized by including the basket-shaped rotor and a stator in which a multi-phase winding is arranged on a stator core.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a cage rotor according to the present invention, a method for producing the cage rotor, and an induction synchronous motor using the cage rotor will be described with reference to the accompanying drawings.

As shown in FIG. 1, an induction synchronous motor according to an embodiment of the present invention has a cylindrical stator 1 incorporated in a housing (not shown) and the stator 1.
And a basket-shaped rotor 2 that is inserted into the.

The stator 1 includes a stator core 3 and a three-phase winding 6 formed on the inner circumference of the stator core 3 and arranged in a conductor groove 5 between, for example, 24 teeth 4. And each phase of the three-phase winding is distributed winding every 6 pitches.

The basket-shaped rotor 2 is fixed to a rotary shaft 7 which is rotatably supported by a pair of bearings (not shown) attached to the housing. This basket-shaped rotor 2
Is a rotor core 9 in which a magnet 8 is axially built in a space between a basket-shaped core 9a and a shaft core 9b, and a rod-shaped copper insert into each conductor groove 10 of the rotor core 9 or It is composed of a plurality of aluminum-made conductors 11 and end rings (not shown) attached to both ends of the rotor core 9 to short-circuit the conductors 11.
Further, a connecting iron portion 12 which is a portion connecting the basket-shaped iron core 9a and the shaft iron core 9b is formed in the void portion at the bottom of the basket-shaped iron core 9a, and the basket iron core 9a and the shaft iron core 9b are connected to each other. The parts 12 are integrally connected. This joint part 12
In the present embodiment, is formed at four positions, which is the number of poles, but can be formed at two positions in the case of, for example, two poles.

The magnet 8 is composed of four magnet pieces 8a, 8b, 8c and 8d having a fan shape, a roof tile shape or an arc shape, and these magnet pieces 8a to 8d are the cage core 9a and the shaft core 9b. It is arranged in a cylindrical space between and.

The rotor core 9 of this embodiment has a four-pole magnet 8 consisting of four divided magnet pieces 8a to 8d, the outer diameter surface of which is fitted to the inner diameter surface of the basket-shaped iron core 9a. The inner diameter surface is fitted to the outer diameter surface of the shaft core 9b.

In the present embodiment, the conductor groove 13 located on the line of the connecting iron portion 12, which is the magnetic pole boundary portion of the basket-shaped iron core 9a and which is the boundary between the adjacent magnet pieces 8a to 8d, is another conductor groove. It is formed in a deep groove larger than 10. The number of the conductor grooves 13 of the deep groove is set to four, which is the same as the number of poles, in order to block the lines of magnetic force emitted from each of the four poles and exert a convex polarity. The shape and size of the bottom portion of the conductor groove 13 can be appropriately determined in consideration of mechanical strength and leakage of magnetic flux. For example, 0.5 to 0.5 mm from the inner diameter surface of the basket-shaped iron core 9a.
It can be formed as long as 1.0 mm.

When the connecting iron portion 12 is provided, the magnetic flux of the magnet 8 leaks through the connecting iron portion 12 in this narrow portion, but the magnetic flux narrowed by the deep conductor groove 13 is used as the connecting iron portion. Part 1
Since the shape is further branched at 2, it does not become so large compared to the leakage magnetic flux in the case where the connecting iron portion 12 is not provided.
This is Φ ≈ φ + ψ (φ:
This is because ψ increases with the bottom magnetic flux of the slot, ψ: magnetic flux of the connecting iron part, but it does not increase so much due to magnetic saturation. That is, the presence or absence of the connecting iron portion 12 does not cause a large difference in characteristics.

The iron core shape in the present embodiment does not have a magnet insertion portion between the basket-shaped iron core and the shaft iron core as the entire circumference void portion, but has a narrow connecting iron portion according to the number of poles. Therefore, since the basket-shaped core and the shaft core are not separated but are connected to each other, the press die design can be facilitated, the manufacturing cost can be reduced, and the assembly can be facilitated.

Next, a method of manufacturing the cage rotor according to this embodiment will be described. The procedure of the manufacturing method is: iron core plate → lamination of iron core plate → jig insertion → formation of conductor and end ring → magnet insertion and jig removal. That is, a thin steel plate is punched out by a die, and a cage rotor piece in which the cage core and the core core material are integrally bonded while leaving the connecting iron portion is manufactured.
Then, after stacking the integrally formed cage core and shaft core material, in the gap between the cage core and the shaft core magnet, the same number, shape and size of the magnets as the non-magnetic material are formed. The body jig is inserted in advance in the space of the magnet insertion part instead of the magnet, and then the conductor (basket winding) and the end ring are formed by the die casting method or the like. Then, the jig is pushed out by the magnet to insert the magnet, and then the cage rotor is assembled.

In this embodiment, the cage core and the shaft core are formed by punching out the base material of the cage core and the shaft core with a die using a thin steel plate, and stacking them to form the cage core and the shaft core. Since both of the shaft cores are not separated but are integrally connected by the connecting iron portion, the manufacturing cost can be reduced, the manufacturing work can be facilitated, and the assemblability can be improved.

In this embodiment, in order to position the magnet 8, it is preferable to form the positioning protrusions 14 for the magnet 8 at the left and right positions of the connecting iron portion 12 on the shaft iron core 9b side. The protrusion 14 facilitates the positioning of the magnet, which further facilitates the assembly of the iron core.

Further, in the present embodiment, the cage rotor having a built-in four-pole cylindrical magnet composed of four magnet pieces is used, but the present invention is not limited to this. A basket-shaped rotor having a two-pole cylindrical magnet built therein can be used. Thus, the number of poles of the magnet (4 poles in the present embodiment) is 1/2 (2 poles in the present embodiment).
If the number of poles is even, a pair of rotor magnetic poles (N pole, S pole) are formed at opposing positions, so that the rotor core can be shared. Therefore, when the number of poles of 1/2 is odd, for example, 6, 10 or 14 poles are excluded.
In the case of a shared iron core, design the one with the smaller number of poles to determine the dimensions. In the opposite case, an increase in the stacking thickness is taken as a countermeasure against saturation, which is disadvantageous in terms of dimensions.

[0022]

As described above, according to the present invention,
It is possible to reduce the manufacturing cost and improve the assemblability.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts showing an embodiment of a cage rotor and an induction synchronous motor of the present invention.

FIG. 2 is an enlarged view of a connecting iron portion of FIG.

FIG. 3 is a cross-sectional view of essential parts showing an example of a conventional induction synchronous motor.

[Explanation of symbols]

1 stator 2 basket-shaped rotor 3 Stator core 4 teeth 5, 10 conductor groove 6 three-phase winding 7 rotation axis 8 magnets 8a, 8b, 8c, 8d Magnet pieces 9 rotor core 9a Basket-shaped iron core 9b shaft iron core 11 conductors 12 Connecting iron part 13 Deep groove conductor groove 14 Projection

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] October 19, 2001 (2001.10.
19)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0002

[Correction method] Change

[Correction content]

[0002]

2. Description of the Related Art Conventionally, a magnet built-in induction synchronous motor, which is an electric motor having the features of both a magnet type synchronous motor and an induction motor, has been developed. For example, as shown in FIG. 3, there is an induction synchronous motor with a built-in magnet in which four magnets 108a to 108d (10 8) are embedded in a cage rotor 102. In this electric motor, the stator 101 has a plurality of teeth 1
04 and the yoke portion 103 that connects the roots of the teeth 104, and has a substantially cylindrical shape. A three-phase winding 106 is provided on the plurality of conductor grooves 105 formed between the plurality of teeth 104. The basket-shaped rotor 102 includes a basket-shaped core 102a having a basket-shaped winding and a shaft-shaped core 102b serving as a core attached to a shaft 107.
01 has a substantially cylindrical shape that is substantially coaxial. The basket-shaped rotor 102 includes a plurality of conductors 111 that are inserted into the conductor grooves 110.
And the number of poles (4) deep grooves arranged at the magnetic pole boundary.
Since the magnet 108 having a substantially cylindrical shape is embedded in the four magnet burying holes penetrating in the axial direction while being supported by the conductors , the four rotors face the inner peripheral surface of the stator 101. It has a magnetic pole. The magnet 108 is magnetized into an N pole and an S pole as shown. Conductor 111 is made of a conductor such as copper or aluminum, by a resistor, caused
The difference in dynamic characteristics is the same as in general induction motors. The basket-shaped rotor 102 is rotated by attracting or repulsing the rotor magnetic poles to the rotating magnetic poles formed by the windings of the stator 101 by the rotating magnetic field formed by the current flowing through the stator windings 106.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5H615 AA01 BB01 BB07 PP03 SS03                       SS05 SS09 SS10 SS12 SS19                       TT05                 5H621 BB10 GA01 GB10 HH01 JK02                       JK05 JK07                 5H622 CA02 CA07 CA10 CB04 PP03                       PP11 PP17 QA10

Claims (4)

[Claims] 1. A rotor core in which a magnet is axially built in a space between a basket-shaped core and a shaft core, a plurality of conductors inserted in respective conductor grooves of the rotor core, and an end point. A basket-shaped rotor comprising a ring, wherein the basket-shaped iron core and the shaft iron core are integrally connected by a connecting iron portion formed in a void portion. 2. The cage rotor according to claim 1, wherein positioning protrusions for the magnet are formed at left and right positions of the connecting iron portion. 3. A rotor core having a magnet axially built in a space between a basket-shaped core and a shaft core, a plurality of conductors inserted in respective conductor grooves of the rotor core, and an end-point contact. A method of manufacturing a basket-shaped rotor comprising a ring, a step of punching a thin steel plate to produce the cage-shaped core and the shaft iron core material integrally coupled, and the cage-shaped core integrally coupled. A step of laminating the core material of the shaft core, a step of inserting a non-magnetic jig corresponding to the magnet into the magnet insertion part in advance in the space between the cage core and the shaft core magnet, And a step of inserting the magnet by pushing out the jig with the magnet. 4. The basket-shaped rotor according to claim 1 or 2,
An induction synchronous motor comprising: a stator having a stator core on which multiphase windings are arranged.