JP2003189564A - Induction motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce loss and improve efficiency by using winding as a conductor of a rotor and reducing a cross current in an induction motor of eight poles. <P>SOLUTION: In the induction motor having a rotor of eight poles, sixteen trenches 1b are formed at an equal interval in the peripheral direction in the rotor 1, and the direction of the trenches 1b is made the axial direction of a rotating shaft 2. In the trenches 1b, two of short-circuit windings 3a-6a of a first to a fourth winding groups 3-6 which turn to short-circuit conductor are subjected to lap winding at two pitches, and the first to fourth winding groups 3-6 are adjacently arranged. Winding for generating a rotating magnetic field is formed in a stator. By the rotating magnetic field, induction short-circuit currents flow in opposite directions through the short-circuit windings (two short-circuit conductors), and magnetic poles are formed. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an 8-pole induction motor used for consumer appliances (for example, air conditioners) and industrial equipment, and more specifically, a novel induction motor using a winding as a rotor conductor. It is about.

[0002]

2. Description of the Related Art An induction motor has a rotor arranged inside a stator that generates a rotating magnetic field. The stator is provided with windings for generating a rotating magnetic field. Has no fixed magnetic poles, that is, no winding like the stator winding is provided.

When the rotor having the short-circuit conductor is arranged in the rotating magnetic field of the stator, a short-circuit induced current flows through the rotor. Rotational force (torque) is generated by the interaction of both the rotating magnetic field and the short-circuit induced current, and the rotor rotates. Such induction motors are widely used in home appliances and industrial machines from the viewpoints of simplicity and economy.

[0004]

By the way, conventionally, the main body (short-circuit conductor) of the rotor is manufactured mainly by casting the conductor by aluminum die casting.

However, since it is difficult to insulate the rotor core from the aluminum conductor, a transverse current (current flowing in the circumferential direction of the rotor core) that does not contribute to torque is applied to the rotor core.
However, there is a drawback in that this causes an increase in loss and reduces the efficiency of the motor.

Further, since it is difficult to use copper having a high electric conductivity as the conductor, an aluminum conductor is used, so that electric loading and magnetic loading are small, resulting in insufficient torque and low efficiency. was there.

The present invention has been made to solve the above problems, and an object thereof is to employ a winding method using a winding as a conductor of a rotor to eliminate a transverse current and reduce a loss. It is intended to provide an induction motor which is improved in efficiency and can be expanded in use range as an 8-pole motor.

[0008]

In order to achieve the above object, the present invention is an eight-pole induction motor in which a rotor is arranged inside a stator that generates a rotating magnetic field. The first to the fourth winding group consisting of the windings are used, and the windings of the first to the fourth winding group are respectively superposed, and an induced short-circuit current is generated in the windings by the rotating magnetic field. It is characterized by making it flow.

2 × 4 × n (n: a positive integer of 2 or more) grooves are formed in the rotor in the axial direction of the rotating shaft and at equal intervals in the circumferential direction, and these grooves are formed. N windings of the first to fourth winding groups are provided at n pitches to sequentially form the first to fourth winding groups, and the first to fourth winding groups By arranging the groups adjacent to each other, a groove having an integral multiple of 8 is formed in the rotor, and the winding as the short-circuit conductor of the rotor can be appropriately provided.

2 × (4 × n + 1) (n;
2 or more positive integer) grooves are formed at equal intervals in the axial direction of the rotary shaft and in the circumferential direction, and the windings of the first to fourth winding groups are formed through these grooves. Each of the first to fourth winding groups is sequentially formed by applying n pieces at n pitches, and one slot is provided between the first winding group and the second winding group. One slot may be provided between the second winding group and the fourth winding.

Further, 2 × (4 × n + 1) (n: a positive integer of 2 or more) grooves are formed in the rotor in the axial direction of the rotating shaft and at equal intervals in the circumferential direction, N windings of each of the first to fourth winding groups are respectively formed through these grooves to sequentially form the first to fourth winding groups, and The third winding group is an n + 1 pitch winding having an empty groove in the center, and the second and fourth windings are n pitch windings, so that the rotor is not an integral multiple of 8. An even number of grooves are formed,
A winding can be properly provided as a short-circuit conductor of the rotor.

2 × (4 × n + 2) (n;
2 or more positive integer) grooves are formed at equal intervals in the axial direction of the rotary shaft and in the circumferential direction, and the windings of the first to fourth winding groups are formed through these grooves. The number of n pitches is n, and the first to fourth winding groups are sequentially formed, and one slot is provided between each winding group. The even number of grooves are formed so that the winding can be properly applied as the short-circuit conductor of the rotor.

Further, 2 × (4 × n + 2) (n; a positive integer of 2 or more) grooves are formed in the rotor in the axial direction of the rotating shaft and at equal intervals in the circumferential direction, The windings of the first to fourth winding groups are respectively n + n through these grooves.
The first to fourth winding groups are sequentially formed by applying n pieces at one pitch, and an empty groove is formed at the center of each winding group.
By providing the slots, an even number of grooves other than the number of grooves of the rotor described above is formed in the rotor, and the winding as the short-circuit conductor of the rotor is appropriately provided.

A capacitor induction motor can be obtained by winding the main winding and the auxiliary winding on the stator by concentrated winding or distributed winding. Also, a capacitor induction motor can be obtained by forming 16 grooves on the inner peripheral side of the stator and winding the main winding and auxiliary winding through concentrated winding through these grooves. As a result, a highly efficient capacitor induction motor using a novel rotor can be realized, and the range of use of the capacitor induction motor can be expanded.

Also, a three-phase AC induction motor can be obtained by winding the above stator with three-phase windings by concentrated winding or distributed winding. Further, two grooves are formed on the inner peripheral side of the stator.
It is possible to obtain a three-phase AC induction motor by forming four pieces and applying concentrated winding of the three-phase winding through these grooves,
As a result, a highly efficient three-phase AC induction motor using a novel rotor can be realized, and the range of use of the three-phase AC induction motor can be expanded.

It is preferable that all the windings applied to the rotor are short-circuited windings. Further, aluminum, aluminum alloy, copper or copper alloy is used for all the windings applied to the rotor, and the windings are connected by pressure welding, welding, soldering or crimping with crimp terminals. It is preferable to use this, because it is possible to use a copper-based material as the winding of the short-circuit conductor of the rotor, which can achieve high torque and high efficiency, and the connection of the short-circuit winding. Can be realized with existing technology.

It is preferable to provide electrical insulation between the windings provided through the grooves of the rotor. Also, electrical insulation may be provided between the rotor core of the rotor and the winding. The grooves of the rotor may be open holes or closed grooves.

As a result, when an induced short-circuit current flows through the winding, the induced short-circuit current does not flow through the rotor core of the rotor, that is, the transverse current is extremely small, loss is small, and high efficiency can be achieved. .

It is preferable that the rotor is obtained by punching electromagnetic steel plates with an automatic laminating die and laminating the rotor cores to obtain a rotor core, and at the time of laminating, skewing the grooves. As a result, the short-circuit winding as the short-circuit conductor of the rotor is applied to the skewed groove, and the torque can be improved.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described in detail with reference to FIGS.

The induction motor of the present invention is basically an 8-pole motor, the rotor of which is 2 × 4 × n on the outer circumference of the rotor core.
(N; a positive integer of 2 or more) grooves are formed, and this 2 × 4
A first winding group in which n pitch windings (closed circuit of short-circuit winding; hereinafter referred to as short-circuit winding) are applied to n grooves, and n short-circuit windings of n pitches are overlapped. The first winding group and the second to fourth winding groups having the same structure are sequentially formed and 4 × n windings are formed.

More specifically, as shown in FIGS. 1 and 2, the rotor 1 of this induction motor includes 16 (n = 2) grooves 1 on the outer peripheral side of a rotor core (rotor core) 1a.
b in the axial direction of the rotary shaft 2 and in the circumferential direction at equal intervals (2
At intervals of 2.5 degrees), two short pitch windings 3a having 2 pitches are lapped at intervals of 1 pitch through the 16 grooves 1b to form a first winding group 3, and the first winding group 3 is formed. 2 adjacent to the winding group 3 and two short-circuited windings 4a having a pitch of 2 are overlapped at intervals of 1 pitch to form a second winding group 4, and adjacent to the second winding group 4, 2 Two short pitch windings 5a each having a pitch of 2 pitches are overlapped to form a third winding group 5, and two short pitch windings 6a each having a two pitch are adjacent to the third winding group 5. The fourth winding group 6 is formed by stacking the windings at pitch intervals and forming eight windings.

According to the rotor 1, 16 short-circuit conductors formed by the first to fourth winding groups 3, 4, 5, 6 are continuous, and the windings of each winding group form two poles. The total number of poles is eight.

Further, as shown in FIGS. 3 and 4, 16 grooves are formed on the inner peripheral side of the stator 7 of this induction motor, that is, teeth of a predetermined width are formed inside the outer peripheral yoke portion 7a. 7
16 b are formed at intervals of 22.5 degrees.
b has concentrated windings 8a, 8b, 8c, 8d, 8e, 8
f, 8g, 8h, 9a, 9b, 9c, 9d, 9e, 9
f, 9g, 9h are applied, and 4 pairs of windings 8a, 8b, windings 8c, 8d, windings 8e, 8f and windings 8g, 8h applied to the facing teeth 7b are used as main windings, and the remaining Tooth 7b
Windings 9a, 9b, windings 9c, 9d, windings 9e,
Four pairs of 9f and windings 9g and 9h are used as auxiliary windings.

In the induction motor having the above-mentioned structure, since the rotating magnetic field is generated in the stator 7, the main windings 8a, 8b, 8c, 8d, 8e, 8f, 8g and 8h are formed as shown in FIG.
And auxiliary windings 9a, 9b, 9c, 9d, 9e, 9f,
Connect 9g and 9h. That is, the auxiliary windings 9a, 9b,
A parallel circuit of the auxiliary windings 9c, 9d, the auxiliary windings 9e, 9f and the auxiliary windings 9g, 9h and the capacitor 10 are connected in series, and the main windings 8a, 8b, the main winding 8c, 8d, main windings 8e, 8f and main winding 8g,
8h parallel circuits are connected in parallel, and the AC power supply 11 is supplied to this parallel circuit. The main winding and the auxiliary winding of the stator 7 may be connected by another connection method.

As a result, the induction motor becomes a capacitor induction motor. In this capacitor induction motor, when a rotating magnetic field is generated in the stator 7, the rotating magnetic field causes an inductive short-circuit current to flow in the short-circuit windings 3a, 4a, 5a, 6a of the rotor 1. These short-circuit windings 3a, 4a, 5
There are two short-circuit conductors due to a and 6a, respectively, and the induced short-circuit currents of these two short-circuit conductors flow in opposite directions (that is, different polarities).

Therefore, due to the interaction between the rotating magnetic field by the stator 7 and the induced short-circuit current, the short-circuit windings 3a, 4a,
Rotational force (torque) in the same rotation direction acts on each of the two short-circuit conductors 5a and 6a, and the rotor 1 rotates.

In the above-described embodiment, the number of grooves of the rotor 1 is 16, but the number of grooves of 2 × 4 × n is formed, and the first winding is provided with n pitches. Even if 4n windings are provided, the same action and effect can be obtained by the winding group and the second to fourth winding groups each having n windings. Although concentrated winding is used as the winding of No. 7, distributed winding may be used.

By the way, in order to manufacture the rotor 1,
Electromagnetic steel plates (belt-shaped) are punched and laminated by an automatic laminating die. At this time, the grooves are skewed and laminated to obtain the rotor core 1a. This allows the short-circuit winding 3
Since a, 4a, 5a and 6a are skewed, the torque of the capacitor induction motor can be increased.

The groove 1b of the rotor 1 is preferably an open hole (see FIG. 1) for ease of manufacturing the rotor 1, but it may be a closed hole. It is preferable that the inside of the groove 1b be insulated. That is, by electrically insulating the rotor core 1a and the short-circuit windings 3a, 4a, 5a, 6a, the rotor core 1a and the short-circuit windings 3a, 4a, 5a are provided.
The a and 6a are electrically insulated from each other, the transverse current is minimized, the loss is not increased, and the motor efficiency is improved.

Further, the short-circuit winding 3a formed in each groove 1b
It is preferable to insulate the wire between the wire, the wire of the short-circuit winding 4a, the wire of the short-circuit winding 5a, and the wire of the short-circuit winding 6a. That is, by using windings having an insulating film formed on each winding by enameling, the transverse current and loss thereof can be further suppressed.

Short-circuit windings 3a, 4a, 5 of the rotor 1
Aluminum, an aluminum alloy, copper or a copper alloy is used as the short-circuit conductors a and 6a, and the connection method may be pressure welding, welding, soldering, or a crimping method using a crimping terminal.

As a result, particularly when a copper-based material is used for the short-circuit windings 3, 4a, 5a, 6a, higher torque and higher efficiency can be achieved as compared with the aluminum-based material. Also,
The existing technique can be applied to the connection method of the short-circuit windings 3a, 4a, 5a, 6a.

Here, the short-circuit windings 3a, 4a of the rotor 1,
Supplementally describing 5a and 6a, since the winding forms a short circuit, the ampere-turn TA generated by the induced voltage is constant if the space factor or the usage amount is the same. To explain the reason, the voltage induced in the short-circuited winding is expressed by the following formulas 1 and 2.

[0035]

[Equation 1]

[0036]

[Equation 2]

N is the number of groove conductors, and the rotor groove conductor cross-sectional area is a value obtained by multiplying the square of the conductor diameter d by the number N of conductors (constant).
Where φ is the main magnetic flux (constant), R is the winding resistance,
X is the reluctance of the winding.

When the number of groove conductors is one (N = N1 =
1), the ampere-turn TA1 can be represented by i1 · N1, and when the number of groove conductors is plural (N = N2), the ampere-turn T
A2 can be represented by i2 · N2. Ampere turns TA1 and T
When compared with A2, the following formula 3 is obtained, that is, TA2 /
TA1 = 1.

[0039]

[Equation 3]

In the above formula 3, when the number of groove conductors is one, the diameter of the winding wire to be applied to the groove is increased, and the winding amount to be applied when the number of groove conductors to be used is plural. By setting the same as the used amount, the ampere-turn AT becomes the same when the number of groove conductors is set to one and the number of groove conductors is set to one.

Therefore, if the rotor groove conductor cross-sectional areas, that is, the space factor, are made equal, the performance as a motor is the same regardless of whether there is one winding or a plurality of windings. It can be said that the torque characteristic of the induction motor by the rotor 1 is equivalent to that of the die cast rotor.

5 to 7 are schematic configuration diagrams of an induction motor showing a second embodiment of the present invention. The rotor 20 in the second embodiment is a rotor core (rotor core).
2 × (4n + 1) (n; positive integer of 2 or more) on the outer circumference side of
The first winding group is formed by forming n grooves and n windings of n pitches (closed circuit of short-circuit winding; hereinafter referred to as short-circuit winding) are superposed on the 2 × (4n + 1) grooves. Forming this first
The second to fourth winding groups having the same structure are sequentially formed in the same manner as the first winding group, and the first winding group and the second winding group are placed every other slot (an empty groove is formed). ), The third winding group and the fourth winding group are placed one slot (an empty groove is formed).

More specifically, as shown in FIG.
Similar to the rotor 1 of the first embodiment, the rotor 20 of the induction motor has 18 (n = 2) grooves on the outer peripheral side of the rotor core (rotor core) in the axial direction of the rotary shaft, and , The first winding group 21 and the two short-circuit windings 22a, which are formed at equal intervals (20-degree intervals) in the circumferential direction, and which are formed of two short-circuit windings 21a via these 18 grooves. The second winding group 22 is formed by arranging one slot, and the second winding group 22 is formed.
A third winding group 23 composed of two short-circuit windings 23a is formed adjacent to the third winding group 23a, and a fourth winding consisting of two short-circuit windings 24a is placed one slot with the third winding group 23a. The line group 24 is formed.

First to fourth winding groups 21, 22, 2
3 and 24 are short pitch windings 21a and 22 of 2 pitches, respectively.
a, 23a, and 24a are overlapped every other one pitch,
One empty groove is formed between the first winding group 21 and the second winding group 22, and the third winding group 23 and the fourth winding group 24 are formed.
And one vacant groove is formed between and.

According to this rotor 20, there are two empty grooves. That is, eight short-circuit conductors are continuous with one groove placed, and two continuous short-circuit conductors are positioned at a predetermined interval. Therefore, similar to the first embodiment, the total number of poles by these 16 short-circuit conductors is eight.

Further, as illustrated in FIGS. 6 and 7,
The stator 25 in the second embodiment has 24 grooves. That is, 24 teeth 25b having a predetermined width are formed inside the outer peripheral yoke portion 25a at intervals of 15 degrees, and concentrated windings 26a, 26b, 26c, 2 are formed on these teeth 25b.
6d, 26e, 26f, 26g, 26h, 27a, 27
b, 27c, 27d, 27e, 27f, 27g, 27
h, 28a, 28b, 28c, 28d, 28e, 28
f, 28g, 28h.

Regarding the above-mentioned 24 windings 26a to 28h, the windings 26a, 26 provided on the teeth 25b facing each other
b, windings 26c and 26d, windings 26e and 26f, and windings 26g and 26h are U-phase windings, and windings 27a and
27b, windings 27c and 27d, windings 27e and 27f, and windings 27g and 27h are four pairs, and
Winding 28a, 28b, winding 28c, 28d, winding 28
e, 28f and four windings 28g, 28h are W-phase windings.

In the induction motor according to the second embodiment, since the rotating magnetic field is generated in the stator 25, the induction motor shown in FIG.
As shown in, the 24 windings 26a to 28h are Y-connected, and a three-phase AC power source is supplied to the Y-connected windings.

In this case, for the U phase, the windings 26a,
26b, windings 26c and 26d, windings 26e and 26f, and windings 26g and 26h are connected in parallel, and for the V phase,
Winding 27a, 27b and winding 27c, 27d and winding 27
e, 27f and windings 27g, 27h are connected in parallel, and W
Regarding the phases, the windings 28a and 28b and the windings 28c and 28
d and windings 28e, 28f and 28g, 28h are connected in parallel. The windings of the stator 25 may be connected by another connection method.

As a result, the induction motor becomes a 3-phase 8-pole induction motor. In this three-phase, eight-pole induction motor, when a rotating magnetic field is generated in the stator 25, the rotating magnetic field causes the short-circuit windings 21a, 22a, 23a of the rotor 20.
An induced short-circuit current flows through 24a (that is, has a different polarity).

The short-circuit windings 21a, 22a, 23a, 2
4a are respectively two short-circuit conductors, and these short-circuit conductors act in the same manner as in the first embodiment, and therefore, due to the interaction between the rotating magnetic field of the stator 25 and the induced short-circuit current,
The two short-circuit conductors in the short-circuit windings 21a, 22a, 23a, and 24a are acted on by the rotational force (torque) in the same rotational direction, and the rotor 10 rotates.

In the embodiment described above, the rotor 20
Although the number of grooves of 18 is set to 18, the same action and effect can be obtained by forming 2 × (4n + 1) number of grooves and forming four winding groups in which n pitch windings are applied. Obtainable. Further, although the concentrated winding is used as the winding of the stator 25, it may be distributed winding.

The rotor 20 and the stator 25 are manufactured in the same manner as in the first embodiment, and for example, the rotor 2
The groove (open hole or closed hole) of 0 is skewed, and the inside of the groove (open hole or closed hole) is electrically insulated.

Further, the short-circuit windings 21a, 22 of the rotor 20
The materials a, 23a, and 24a are made of the same material and connection method as those described in the first embodiment, and are insulated. Therefore, also in the second embodiment, the same effect as that of the first embodiment can be obtained.

As described above, also in the second embodiment, by adopting the winding method using the copper wire or the aluminum wire as the short-circuit conductor of the rotor, the transverse current is extremely small, the loss is small, and the motor is small. Efficiency is improved.

FIG. 8 is a schematic diagram of a rotor of an induction motor showing a modification of the second embodiment. The rotor 30 in this modified example has the same structure as in the second embodiment described above.
(N = 2) grooves are formed at equal intervals (20 ° intervals) in the axial direction of the rotating shaft and in the circumferential direction, and two short-circuited windings are formed through these 18 grooves. First to fourth winding groups 31, 32, 33, 34 are provided.

In the first winding group 31, two 3-pitch short-circuit windings 31a are laid one on another at a pitch, and
An empty groove of 1 slot is formed in the center thereof. The second winding group 32 is provided by adjoining the first winding group 31 by stacking two 2-pitch short-circuit windings 32a every other pitch.
The third winding group 33 is adjacent to the second winding group 32 and
Similarly to the winding group 31 of No. 3, two short-circuit windings 33a of 3 pitches are lapped and placed every other pitch, and the fourth winding group 34 is
Adjacent to the third winding group 33, two short-circuit windings 34a having two pitches, which are the same as those of the second winding group 32, are superposedly wound every other pitch.

In this case, the short-circuit winding 31a of the rotor 30
As the short-circuit conductors 32a, 33a, and 34a, eight short-circuit conductors are continuous and eight short-circuit conductors are continuous with one groove, and the short-circuit conductors are arranged in the same manner as in the second embodiment. Has been done.

Therefore, in this induction motor,
The same configuration as the stator 20 of the second embodiment (U phase, V
Phase and W-phase winding configuration)
An induced short-circuit current flows through the short-circuit windings 31a, 32a, 33a, 34a due to the rotating magnetic field of the stator 20, and the rotor 30 rotates due to the same action as in the second embodiment.

Also in this modification, at least the operation and effect described in the second embodiment can be obtained. That is,
In this modified example, in the second embodiment, the groove (fifth and fourteenth slot) where the short-circuit winding is not formed is the first groove.
This is because they are provided at the center of the winding group 31 and the center of the third winding group 33 (third and twelfth slots; see FIG. 8), and there is no essential difference.

Although the rotor 30 has 18 grooves, 2 × (4n + 1) grooves are formed to obtain n + 1.
The same action and effect can be obtained by forming four winding groups with n pitch windings.

FIG. 9 is a schematic diagram of a rotor of an induction motor showing a third embodiment of the present invention. A rotor 40 in the third embodiment has a rotor core (rotor iron core) 2 × on the outer peripheral side. (4n + 2) (n; a positive integer of 2 or more) grooves are formed, and n pitch windings (closed winding closed circuit; hereinafter referred to as short-circuit windings) are formed through these 2 × (4n + 2) grooves. ) N
The first winding group is formed by winding the individual windings, and second to fourth winding groups having the same structure are sequentially formed in the same manner as the first winding group, and the first to fourth winding groups are formed. An empty groove is provided between the line groups.

More specifically, as shown in FIG.
The rotor 40 of this induction motor has 20 (n = 2) grooves on the outer peripheral side of the rotor core (rotor core) in the axial direction of the rotary shaft, as in the rotor 20 of the second embodiment. , A first winding group 41 formed of two short-circuit windings 41a that are formed at equal intervals (18 degrees apart) in the circumferential direction, and these first winding group 41 The second to fourth winding groups 42, 43, 44 each having two short-circuited windings 42a, 43a, 44a, respectively, having the same configuration as the above, are sequentially provided.

First to fourth winding groups 41, 42, 4
3 and 44 are short pitch windings 41a and 42 of 2 pitches, respectively.
a, 43a, and 44a are overlapped at intervals of one pitch, and are provided between the first to winding groups 41, 42, 43, and 44,
In other words, there is a slot with 1 slot between each winding group (4 slots in total).
Individual pieces) are formed.

According to this rotor 40, there are four empty grooves. That is, four short-circuit conductors are continuous with one groove placed, and four continuous short-circuit conductors are positioned at a predetermined interval. Therefore, the four short-circuit conductors form two poles, and the total number of poles is eight, and it can be used as a rotor of an eight-pole induction motor. In this case, according to the structure of the short-circuit conductor of the rotor 40, a 3-phase 8-pole induction motor can be realized by using the same stator 25 as in the second embodiment.

FIG. 10 is a schematic diagram of a rotor of an induction motor showing a modified example of the third embodiment. In this modification, the rotor 50 is the rotor 4 of the third embodiment.
In the same way as 0, 20 on the outer peripheral side of the rotor core (rotor core)
The grooves are formed at equal intervals in the axial direction of the rotary shaft and in the circumferential direction, and the two short-circuit windings 5 are provided through these 20 grooves.
A first winding group 51 composed of 1a and two short-circuit windings 52a, 53a, 5 each having the same configuration as the first winding group 51.
Second to fourth winding groups 52, 53, 54 composed of 4a
And are made adjacent to each other in order.

First to fourth winding groups 51, 52, 5
3 and 54 are short pitch windings 51a and 52 of 3 pitches, respectively.
a, 53a, and 54a are overlapped at intervals of 1 pitch, and the first to fourth winding groups 51, 52, 53, and 54 are formed.
In the center (center of each winding group), a 1-slot vacant groove (total of 4) is formed.

According to the rotor 50, in the third embodiment, the vacant groove is provided between the first to fourth winding group 41 to 44, whereas the first to fourth winding group 5 is provided.
An empty groove is formed in the central portion of 1, 52, 53, 54.

In this case, the center of the magnetic pole of the rotor 50 is slightly shifted from the center of the magnetic pole of the rotor 40 of the third embodiment and does not completely match, but this is not essentially different. Therefore, the rotor 50 can be used as a rotor of an 8-pole induction motor.

According to the structure of the short-circuit conductor of the rotor 50, a 3-phase 8-pole induction motor can be realized by using the same stator 25 as in the third embodiment. In addition, the rotors 1, 20, 30, 40, 50 and the stators 7, 25
The combination with and can realize an induction motor with eight poles other than the above.

[0071]

As described above, according to the present invention,
The windings of the first to fourth winding groups are used as the short-circuit conductors of the rotor inside the stator, and the plurality of windings of the first to fourth winding groups are overlapped respectively to form a stator. By making the induced short-circuit current flow through these windings by the rotating magnetic field of, the transverse current in the rotor is extremely small compared to the short-circuit conductor by aluminum die casting, loss is small, high efficiency can be improved, and eventually 8 There is a useful effect that it can be expected to expand the range of use as a pole motor.

[Brief description of drawings]

FIG. 1 is a plan view schematically showing a rotor of an induction motor according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram for explaining a winding connection relation of the rotor shown in FIG.

FIG. 3 is a plan view schematically showing a configuration of a stator side of the induction motor according to the first embodiment.

FIG. 4 is a schematic circuit diagram showing a connection state of windings applied to the stator shown in FIG.

FIG. 5 is a schematic diagram for explaining a winding connection relationship of a rotor of an induction motor according to a second embodiment of the present invention.

FIG. 6 is a plan view schematically showing a configuration of a stator side of the induction motor according to the second embodiment.

7 is a schematic circuit diagram showing a connection state of windings applied to the stator shown in FIG.

FIG. 8 is a schematic diagram for explaining a winding connection relation of a rotor of an induction motor according to a modified example of the second embodiment.

FIG. 9 is a schematic diagram for explaining a winding connection relationship of a rotor of an induction motor according to a third embodiment of the present invention.

FIG. 10 is a schematic diagram for explaining a winding connection relationship of a rotor of an induction motor according to a modified example of the third embodiment.

[Explanation of symbols]

1, 20, 30, 40, 50 Rotor 1a Rotor core (rotor iron core) 1b Groove 2 Rotating shafts 3a to 6a Short-circuit winding (conductor of rotor 1; winding of closed circuit) 3, 21, 31, 41, 51 first winding group 4, 22, 32, 42, 52 second winding group 5, 23, 33, 43, 53 third winding group 6, 24, 34, 44, 54 fourth winding group Wire group 7,25 Stator 7b, 25b Teeth 8a-8h, 9a-9h Winding 21a-24a of stator 7 Short-circuit winding (conductor of rotor 20; winding of closed circuit) 26a-26h, 27a-27h , 28a to 28h Windings 31a to 34a of the stator 25 Short-circuit windings (conductor of the rotor 30; windings of closed circuit) 41a to 44a Short-circuit windings (conductors of the rotor 40; winding of closed circuit) 51a- 58a Short-circuit winding (conductor of rotor 50; winding of closed circuit)

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H02K 17/12 H02K 17/12 AF term (reference) 5H013 DD01 DD03 FF01 FF03 LL00 MM00 NN01 NN05 NN06 PP01 PP03 5H604 BB01 BB09 BB14 CC01 CC02 CC05 CC14 CC15 PB02 PB03 5H615 AA01 BB01 BB06 BB14 PP03 PP09 QQ02 SS03 SS05 SS16 TT14 TT15 TT16

Claims (16)

[Claims] 1. An eight-pole induction motor in which a rotor is arranged inside a stator that generates a rotating magnetic field, wherein first to fourth winding groups including a plurality of windings are used as conductors of the rotor. An induction motor characterized in that the windings of the first to fourth winding groups are overlapped with each other, and an induced short-circuit current flows through the windings by the rotating magnetic field. 2. The rotor has 2 × 4 × n (n; 2)
The above positive integer) groove in the axial direction of the rotation axis, and
2. The induction motor according to claim 1, wherein the induction motor is formed at equal intervals in the circumferential direction, and n windings of each of the first to fourth winding groups are overlapped with each other by n pitches through these grooves. 3. The rotor is formed with 2 × (4 × n + 1) (n; positive integers of 2 or more) grooves in the axial direction of the rotating shaft and at equal intervals in the circumferential direction. Then, n windings of each of the first to fourth winding groups are provided through these grooves at an n pitch, and an empty groove is provided between the first winding group and the second winding group. The induction motor according to claim 1, wherein one slot is provided, and one slot is provided between the second winding group and the fourth winding. 4. The rotor is formed with 2.times. (4.times.n + 1) (n; a positive integer of 2 or more) grooves at equal intervals in the axial direction of the rotating shaft and in the circumferential direction. Then, n windings of the first to fourth winding groups are respectively provided through these grooves, and the first winding group and the third winding group each have an empty groove at the center (n + 1). In addition to the pitch winding,
The induction motor according to claim 1, wherein the second and fourth windings are n-pitch windings. 5. The rotor is formed with 2 × (4 × n + 2) (n; a positive integer of 2 or more) grooves at equal intervals in the axial direction of the rotating shaft and in the circumferential direction. Then, n windings of the first to fourth winding groups are respectively provided through these grooves at n pitches to sequentially form the first to fourth winding groups, and each winding group is formed. The induction motor according to claim 1, wherein one slot is provided between the slots. 6. The rotor is formed with 2 × (4 × n + 2) (n; a positive integer of 2 or more) grooves at equal intervals in the axial direction of the rotating shaft and in the circumferential direction. Through the grooves, the windings of the first to fourth winding groups are respectively n +
The first to fourth winding groups are sequentially formed by applying n pieces at one pitch, and an empty groove is formed at the center of each winding group.
The induction motor according to claim 1, which is provided with a slot. 7. The induction motor according to claim 1, wherein the stator is provided with main windings and auxiliary windings by concentrated winding or distributed winding to form a capacitor induction motor. 8. A capacitor induction motor, wherein 16 grooves are formed on the inner peripheral side of the stator, and main windings and auxiliary windings are concentratedly wound through these grooves to form a capacitor induction motor. Or the induction motor according to 2. 9. A three-phase AC induction motor, wherein a three-phase winding is concentratedly or distributedly wound on the stator.
The induction motor according to 3, 4, 5 or 6. 10. A three-phase AC induction motor, wherein 24 grooves are formed on the inner peripheral side of the stator, and three-phase windings are concentratedly wound through these grooves to form a three-phase AC induction motor. Three
The induction motor according to 4, 5, or 6. 11. The induction motor according to claim 1, wherein all the windings applied to the rotor are short-circuited windings. 12. All of the windings applied to the rotor are made of aluminum, aluminum alloy, copper or copper alloy, and the windings are connected by pressure welding, welding,
The induction motor according to any one of claims 1 to 11, which employs either soldering or crimping with a crimp terminal. 13. The induction motor according to claim 2, wherein electrical insulation is provided between windings provided through the groove of the rotor. 14. The induction motor according to claim 2, wherein electrical insulation is provided between the rotor core and the winding of the rotor. 15. The induction motor according to claim 2, wherein the groove of the rotor is an open hole or a closed groove. 16. The rotor according to claim 2, wherein an electromagnetic steel plate is punched by an automatic laminating die and laminated to obtain a rotor core, and a groove is skewed when laminating the rotor core. Induction motor.