JP2003333811A - Induction motor having a plurality of axially divided stator windings - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an induction motor which is low in cost, small in size, light in weight, and has high efficiency by a winding system in which a coil end does not exist, and stator structure. <P>SOLUTION: In a single-phase induction motor, two kinds of coils 10 and 11 are wound in ring forms to an axially divided stator 20, and they are arranged so that the center of the ring of each coil and the center of a rotary shaft 90 roughly coincides with each other, and stator iron cores which constitute magnetic circuits on the external peripheral side of each coil and on both sides in the axial direction, is provided. On the side of its internal periphery, magnetic pole teeth 30-33 are made alternately in positions which are slid by πin an electrical angle in the circumferential direction of the rotary shaft across each coil, and further the magnetic pole teeth of each coil are overlapped axially, being slid by π/2 in an electrical angle in the circumferential direction of the rotary shaft. In a three-phase induction motor, coils are of three kinds, and the magnetic pole teeth of each coil are slid by 2π/3 in an electrical angle from one another. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-phase induction motor such as a capacitor motor, a capacitor starting motor, and a phase-dividing starting motor which are operated by a single-phase power source, and a three-phase induction motor which is operated by a three-phase power source. The present invention relates to an electric motor, and particularly to a winding method and a stator core structure.

[0002]

2. Description of the Related Art Conventionally, as a motor of this type, for example, when a three-phase induction motor is taken as an example, a structure shown in FIG. 16 is generally adopted. FIG. 16A is a side view of a half section in the axial direction. The stator core 120 is provided with a U / V / W phase coil 110, as shown in the winding development view of FIG. After being wound by, the terminal treatment such as the connection between the winding wires and the lead wire connection is performed.

[0003]

In the conventional three-phase induction motor as described above, the U / V / W-phase coil 110 is used.
Is distributed in the circumferential direction for winding, so that the stator core 12
The length h of the coil end protruding from the end face in the axial direction of 0 becomes large, and it is difficult to reduce the size and weight and reduce the cost due to an increase in the winding amount and copper loss due to the coil end that does not contribute to the characteristics. There is. The single-phase induction motor also has the same problem because the main winding and the auxiliary winding are circumferentially distributed and wound around the stator core.

The present invention has been made in order to solve the above-mentioned problems, and since there is no coil end, the winding method and stator core structure of an induction motor are small, lightweight, highly efficient and low cost. The purpose is to get.

[0005]

In order to achieve the above object, an induction motor according to the present invention has a stator in which a plurality of coils are axially divided and wound in a ring shape. Arranged so that the center and the center of the rotary shaft are substantially coincident with each other, stator iron cores forming a magnetic circuit are provided on the outer peripheral side of each coil and both ends in the axial direction. With an electrical angle of π in the circumferential direction of the rotating shaft.
The magnetic pole tooth portions of the coils are alternately formed at different positions, and the magnetic pole tooth portions of the respective coils are shifted in the circumferential direction of the rotating shaft by a predetermined angle so as to be superposed in the axial direction.

An induction motor according to the next invention further comprises:
Each magnetic pole tooth portion formed on the stator core on both axial ends of the coil is provided with a magnetic pole piece composed of a magnetic member.

An induction motor according to the next invention further comprises:
The stator is provided with means for reducing leakage of magnetic flux.

An induction motor according to the next invention further comprises:
At least a part of the stator core is laminated and formed by using a plate-shaped magnetic member.

An induction motor according to the next invention further comprises:
At least a part of the stator core is formed by using a dust core.

An induction motor according to the next invention further comprises:
The stator or rotor is skewed.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an induction motor according to the present invention will be described in detail below with reference to the accompanying drawings.

Embodiment 1. 1 to 3 show an example in which a first embodiment of an induction motor according to the present invention is applied to a capacitor motor as a 4-pole single-phase induction motor having two types of axially divided stator windings. Show. Figure 1
[Fig. 3] is a side view of a half section in the axial direction, showing the A-phase / B-phase coil 1
0 and 11, the lead wire 13, the stator 20, the cage rotor 80, the rotating shaft 90, the bearing member 91, the bracket 92,
It is composed of a frame 93 and the like. In this embodiment, the A-phase coil forms the main winding and the B-phase coil forms the auxiliary winding.

The A-phase and B-phase coils 10 and 11 are divided in the axial direction of the rotary shaft 90 and wound so that the center of the ring of each coil 10 and 11 and the center of the rotary shaft 90 are substantially aligned. After being properly insulated, the lead wire 13 is connected to the single-phase power supply 15 together with the capacitor 14 as shown in FIG.

The stator 20 includes coils 10 and 11, rear stator cores 21 and 22 on the outer peripheral side of the coils, and the coils 10 and 11.
11 is composed of the side surface stator cores 24 to 27 on both axial ends, and the A-phase rear surface stator core 21 and the side surface stator cores 24 and 25 are magnetically connected to each other, and the side surface stators are further formed. Magnetic pole teeth 30, 3 are provided on the inner peripheral side of the iron cores 24, 25.
1 are formed respectively. The B-phase stator has the same structure and magnetic pole teeth 32 and 33 are formed on the inner peripheral side.

The cage rotor 80 is rotatably supported by a rotating shaft 90 and a bearing member 91 via magnetic pole teeth 30 to 33 of the A-phase / B-phase coils 10 and 11 and a predetermined air gap. .

3 (a) to 3 (d) show the configuration of the side surface stator cores 24 to 27 and the convex magnetic pole tooth portions 30 to 33 formed on the inner peripheral side thereof, respectively. It is the figure which looked through from the anti-load side to the load side (shaft end side), and other components are omitted in the figure. FIG. 3A shows a side surface stator core 24 on the anti-load side of the A-phase coil 10, and the magnetic pole tooth portions 30 are arranged such that the centers in the circumferential direction thereof are at the 12 o'clock and 6 o'clock positions of the timepiece. It is formed in two places. FIG. 3B shows a side stator iron core 25 on the load side of the A-phase coil 10, and the magnetic pole tooth portion 31 has a magnetic pole whose center in the circumferential direction is formed on the side stator iron core 24 on the anti-load side. It is formed at a position deviated by an electrical angle from the center of the tooth portion 30. As a result, the magnetic poles of four poles pass through the rear stator core 21 (not shown) in the circumferential direction on the inner peripheral side by the magnetic pole tooth portions 30 and 31 of the side stator cores 24 and 25 with the A-phase coil 10 interposed therebetween. They are formed alternately.

FIG. 3 (c) shows a side stator iron core 26 of the B-phase coil 11 on the anti-load side, and the magnetic pole tooth portion 32 has a circumferential center at the side of the A-phase coil 10 on the anti-load side. The magnetic pole tooth portion 30 formed on the stator core 24 is displaced from the center by an electrical angle of π / 2. FIG. 3 (d) shows B
It is the side stator iron core 27 on the load side of the phase coil 11, and the magnetic pole tooth portion 33 has a center in the circumferential direction with respect to the center of the magnetic pole tooth portion 32 formed on the side stator iron core 26 on the anti-load side.
It is formed at a position shifted by π in electrical angle. As a result, A
The rear stator core 22 is provided at a position separated from the magnetic pole tooth portions 30 and 31 of the main winding of the phase coil 10 by an electrical angle of π / 2.
The magnetic poles of four poles through (not shown) sandwich the B-phase coil 11 and magnetic pole tooth portions 32 and 33 of the side surface stator cores 26 and 27.
Thus, they are alternately formed in the circumferential direction on the inner circumferential side.

The stator 20 includes the above-mentioned coils 10 and 11 of A-phase and B-phase, the rear stator cores 21 and 22 on the outer peripheral side,
Also, the side surface stator cores 24 to 27 of the respective coils are configured to be superposed in the axial direction while maintaining the above-mentioned positional relationship.

In the present embodiment, for example, the magnetic flux generated by the A-phase coil 10 has a rear stator core 21 on the outer peripheral side, a side stator core 24, and a magnetic pole tooth portion 30.
→ predetermined air gap → basket-shaped rotor 80 → predetermined air gap → magnetic pole tooth portion 31 → side surface stator core 25 → rear surface stator core 21 to form a magnetic path, and the ring-shaped coil 10 axially forms the magnetic path. The change of the generated magnetic flux can be changed into the change of the magnetic flux in the rotation direction. The magnetic flux generated by the B-phase coil 11 also shifts the magnetic pole tooth portions 32 and 33 in the circumferential direction by an electrical angle of π / 2 in accordance with the phase difference caused by the capacitor 14 connected to the power source. As a result, a two-phase rotating (moving) magnetic field about the rotating shaft 90 is generated by the coils 10 and 11, and the cage rotor 80 can be driven to rotate by electromagnetic induction. . Further, by changing the connection position of the condenser 14 or the like, the rotary shaft 90 can be reversely rotated like the conventional condenser motor.

According to the above construction, since the portion corresponding to the coil end does not exist, the amount of copper wire used in the coil can be reduced and the copper loss can be reduced, and the efficiency of the single-phase induction motor can be improved. It is also possible to realize cost reduction and downsizing / weight reduction. Further, the coil winding work and the terminal treatment can be simplified, and automation by a dedicated machine is possible, which can contribute to the improvement of productivity.

Embodiment 2. 4 to 6 show, as a second embodiment of the induction motor according to the present invention, an example applied to a four-pole three-phase induction motor having three types of axially divided stator windings. FIG. 4 is a side view in the axial half section, showing U, V, and W phase coils 10 to 12 and lead wires 13,
And a stator 20, a basket-shaped rotor 80, a rotary shaft 90, a bearing member 91, a bracket 92, a frame 93, and the like.

The U, V and W phase coils 10 to 12 are divided in the axial direction of the rotating shaft 90 so that the center of the ring of each coil 10 to 12 and the center of the rotating shaft 90 are substantially aligned.
It is wound around the rotary shaft 90 in the same direction. After each coil is properly insulated and connected in a Y shape,
The lead wire 13 is connected to the three-phase power supply 16 as shown in FIG.

The stator 20 includes coils 10 to 12, rear stator cores 21 to 23 on the outer peripheral side of the coils, and the coil 10.
.. 12 side axial stator cores 24 to 29 on both ends in the axial direction, the U-phase rear stator core 21 and the lateral stator cores 24 and 25 are magnetically connected to each other, and further side fixed. On the inner peripheral side of the child iron cores 24, 25, the magnetic pole tooth portion 3
0 and 31 are formed respectively. The V and W phases are similarly configured, and magnetic pole tooth portions 32 to 35 are formed on the inner peripheral side.

The cage rotor 80 is rotatably supported by a rotary shaft 90 and a bearing member 91 via magnetic pole teeth 30 to 35 of U, V and W phase coils 10 to 12 and a predetermined air gap. ing.

6 (a) to 6 (f) show the structure of the side surface stator cores 24 to 29 and the convex magnetic pole tooth portions 30 to 35 formed on the inner peripheral side thereof, which are shown in FIG. It is the figure which looked through from the load side to the load side (shaft end side), and other components are omitted in the figure. FIG. 6A shows the side stator core 24 on the anti-load side of the U-phase coil 10, and the magnetic pole tooth portions 30 are arranged such that their circumferential centers are at the 12 o'clock and 6 o'clock positions of the timepiece. It is formed in two places. FIG. 6B shows the U-phase coil 1.
No. 0 side load side stator core 25 and magnetic pole teeth 31
Is the side surface stator core 2 on the side opposite to the load side in the circumferential direction.
Π in electrical angle with respect to the center of the magnetic pole tooth portion 30 formed in FIG.
It is formed at a shifted position. As a result, the magnetic poles of four poles pass through the rear surface stator core 21 (not shown) and the magnetic pole tooth portions 30 of the side surface stator cores 24 and 25 sandwich the U-phase coil 10.
・ By 31, it is formed alternately in the circumferential direction on the inner circumferential side.

FIG. 6 (c) shows the side stator iron core 26 of the V-phase coil 11 on the anti-load side, and the magnetic pole tooth portion 32 has its circumferential center at the side of the U-phase coil 10 on the anti-load side. The magnetic pole tooth portion 30 formed on the stator core 24 is displaced from the center by an electrical angle of 2π / 3. FIG.6 (d) is
The side stator iron core 27 on the load side of the V-phase coil 11,
The magnetic pole tooth portion 33 is formed such that its circumferential center is deviated from the center of the magnetic pole tooth portion 32 formed in the side load side stator core 26 on the anti-load side by an electrical angle of π. As a result, as in the case of the U-phase coil 10, the rear stator core 2
Through 4 (not shown), the four-pole magnetic pole is the V-phase coil 11
The magnetic pole tooth part 32.3 of the side stator core
3 are alternately formed in the circumferential direction on the inner circumferential side.

FIG. 6 (e) shows the side stator iron core 28 of the W-phase coil 12 on the anti-load side, and the magnetic pole tooth portion 34 has its circumferential center at the side of the U-phase coil 10 on the anti-load side. The magnetic pole tooth portion 30 formed on the stator core 24 is displaced by an electrical angle of 4π / 3 from the center. FIG. 6 (f) shows
A side stator core 29 on the load side of the W-phase coil 12,
The magnetic pole tooth portion 35 is formed such that its center in the circumferential direction is deviated from the center of the magnetic pole tooth portion 34 formed on the side load side stator core 28 on the anti-load side by an electrical angle of π. As a result, as in the case of the U and V phases, the magnetic poles of four poles through the back surface stator core 23 (not shown) sandwich the W phase coil 12 and the magnetic pole tooth portions 34 of the side surface stator cores 28 and 29. By 35, they are alternately formed in the circumferential direction on the inner circumferential side.

The stator 20 includes the above-mentioned U, V, and W phase coils 10 to 12 and the rear stator cores 21 to 2 on the outer peripheral side.
3, and the side surface stator cores 24 to 29 of the respective coils are configured to be superposed in the axial direction while maintaining the above positional relationship.

In the present embodiment, for example, the magnetic flux generated by the U-phase coil 10 has a rear stator core 21 on the outer peripheral side, a side stator core 24, and a magnetic pole tooth portion 30.
→ predetermined air gap → basket-shaped rotor 80 → predetermined air gap → magnetic pole tooth portion 31 → side surface stator core 25 → rear surface stator core 21 to form a magnetic path, and the ring-shaped coil 10 axially forms the magnetic path. The change of the generated magnetic flux can be changed into the change of the magnetic flux in the rotation direction. V / W phase coil 11
The magnetic flux generated by 12 can also act similarly because the magnetic pole tooth portions 32 to 35 are shifted by 2π / 3 in electrical angle in the circumferential direction corresponding to the phase difference of the power supply. As a result, the coil 10 By supplying a three-phase power source to ~ 12, a three-phase rotating magnetic field centering on the rotating shaft 90 is generated,
The cage rotor 80 can be rotationally driven by the electromagnetic induction action. Furthermore, like the conventional three-phase induction motor,
By replacing any two coils of the U, V, and W phase coils with the power supply and connecting them in reverse, the order of phase rotation is reversed, and the direction of the torque acting on the cage rotor 80 is opposite. Therefore, the rotating shaft 90 can be reversely rotated. Further, when the winding directions of the coils 10 to 12 are not the same, the magnetic pole tooth portions can be operated in the same manner by shifting the magnetic pole tooth portion by an electrical angle of π in the circumferential direction of the rotating shaft.

According to the above-mentioned structure, since there is no portion corresponding to the coil end, the amount of copper wire used in the coil is reduced and the copper loss is reduced, thereby contributing to the improvement of the efficiency of the three-phase induction motor. It is also possible to realize cost reduction and downsizing and weight reduction. Further, since the number of coils for each phase is at least one, it is possible to greatly simplify coil winding work and terminal processing. In a large-capacity model, it is also possible to divide each phase coil into a plurality of pieces and arrange them in the axial direction, and employ Δ connection or Y-Δ activation.

Embodiment 3. FIG. 7 shows Embodiment 3 of the induction motor according to the present invention. In the third embodiment, the magnetic pole teeth of the side surface stator core of the above-described first or second embodiment is provided with a magnetic pole piece made of a magnetic member, and each side surface stator core and the magnetic pole teeth are provided. The positional relationship between the cage rotor and the cage rotor is the same as in the first or second embodiment.

FIGS. 7A and 7C show the coil 10
The side surface stator cores 24 and 25 (not shown in the figure) are the same as those in the first or second embodiment, as shown in FIG.
7A and 7B show a view seen from the anti-load side to the load side (shaft end side) of FIG. 7, FIG. 7B being a cross section AA in FIG. 7A, and FIG. 7D being a cross section BB in FIG. 7C. Indicates. The magnetic pole tooth portion 30 of the side stator iron core 24 on the anti-load side has the same inner diameter dimension as that of the magnetic pole tooth portion 30 in the direction of the side stator iron core 25 on the load side which is paired with the side magnetic pole tooth portion 30, and is made of a magnetic member. The pole piece 40 is provided on the inner diameter side of the coil 10. Load side lateral stator core 2
The magnetic pole tooth portion 31 of No. 5 is provided with a magnetic pole piece 41 having the same inner diameter dimension as that of the magnetic pole tooth portion 31 in the direction opposite to the magnetic pole piece 40 in the direction of the side load side stator iron core 24.

FIG. 7E shows the assembled state of the side surface stator cores 24 and 25 having the magnetic pole pieces 40 and 41, and FIG. 7F shows the cross section CC of FIG. 7E. The magnetic pole tooth portion 30 and the magnetic pole piece 40 of the side surface stator core 24 are the magnetic pole tooth portion 31 and the magnetic pole piece 4 of the side surface stator core 25 which are adjacent poles in the circumferential direction.
1 and the magnetic pole tooth portion formed on the side surface stator core of the other coil are also configured with similar magnetic pole pieces.

According to the above-mentioned structure, the magnetic flux generated in each coil can be effectively utilized by each magnetic pole piece, and the leakage magnetic flux is also reduced, so that the efficiency of the induction motor is improved and it contributes to downsizing. can do.

Fourth Embodiment FIG. 8 shows Embodiment 4 of the induction motor according to the present invention. In the fourth embodiment, a = 0 in the above-described third embodiment, and the magnetic pole pieces, the magnetic pole tooth portions, and the magnetic pole pieces that are adjacent to each other in the circumferential direction are connected by the bridge portion.

FIG. 8A shows the side surface stator cores 24 and 25 of the coil 10 (not shown in the drawing) as shown in FIG.
The assembled state is shown as in (e). The magnetic pole tooth portion 30 and the magnetic pole piece 40 of the side surface stator core 24 are arranged such that the magnetic pole tooth portion 31 and the magnetic pole piece 4 of the side surface stator core 25 adjacent to each other in the circumferential direction.
1 is connected by a bridge portion E on the inner peripheral side facing the cage rotor 80 (not shown in the drawing). Figure 8
FIG. 8B is an enlarged view of the bridge portion E of FIG. 8A, and s indicates the radial thickness of the bridge portion. Figure 8
8C shows a cross section CC of FIG. 8A, and the inner peripheral side facing the cage rotor 80 has a continuous cylindrical shape without notches. Similar bridge portions are formed on the magnetic pole teeth formed on the side surface stator cores of the other coils and the magnetic pole pieces.

According to the above-mentioned structure, the dimensional accuracy of the side stator core and the inner circumference of the pole piece can be improved, and the leakage flux can be improved by optimizing the size and shape of the bridge portion. Since it is possible to secure the strength of the pole piece while suppressing the decrease in the gap magnetic flux density due to
The rigidity is improved and the generation of vibration and noise can be reduced.

Embodiment 5. In the fifth embodiment, in addition to the configuration of the above-described embodiment, as a means for reducing the leakage of the magnetic flux of the stator core, a magnetic gap is provided between the phases adjacent to each other in the axial direction. .

FIG. 9 (a) shows A-phase / B-phase of a single-phase induction motor.
It is a half-section side view in the axial direction showing the assembled state of the phase stator and the frame 93, and other components are omitted in the figure. The A-phase stator is composed of the coil 10, the side surface stator cores 24 and 25 on both axial ends, and the rear surface stator core 21, and the B-phase stator is also composed of the coil 11 and the stator core. However, a predetermined gap b is provided as a magnetic gap between the A-phase stator core and the B-phase stator core that are adjacent to each other.

FIG. 9B shows another embodiment. Compared to FIG. 9A, the rear stator cores 21 and 22 are connected and integrally formed, but they are adjacent to each other. Between the phase side stator core 25 and the B phase side stator core 26,
A predetermined gap b is provided as a magnetic gap.

FIG. 10 shows still another embodiment, which is A
The magnetic pole pieces 40 formed on the side surface stator cores 24 of the phases are formed from the axial end faces of the side surface stator cores 25 on the B phase side adjacent to each other.
The magnetic pole pieces formed on the B-phase side surface stator iron core 27 are formed to be shorter than the axial dimension of the adjacent A-phase side surface stator iron core 26 by a predetermined dimension c. It is configured to be short.

According to the above-mentioned structure, by optimizing the dimension b or c, the leakage of the magnetic flux to the adjacent phase can be reduced and the gap magnetic flux density can be secured, so that the single-phase induction motor can be obtained. The characteristics of can be improved.

Similarly, in the case of a three-phase induction motor, the U-phase and V-phase
By providing the air gap b or c between the V-phase and the V-phase and the W-phase, it is possible to reduce the leakage of the magnetic flux to the adjacent phase, so that the characteristics of the three-phase induction motor can be improved. In addition, in both single-phase and three-phase cases, voids b or c
Even if a non-magnetic member is used without forming a gap, the same effect can be obtained.

Sixth Embodiment FIG. 11 shows Embodiment 6 of the induction motor according to the present invention. Sixth Embodiment
Then, as a means for realizing the configuration of the above-described embodiment, a part of the stator core is laminated and integrated by using a plate-shaped magnetic member.

11 (a) and 11 (c) show the coil 1
Similarly to Embodiment 1 or 2, the side stator cores 24 and 25 of 0 (omitted in the drawing) are seen from the anti-load side to the load side (shaft end side) in FIG. 1 or 4. Figure shown. A magnetic pole piece 41 is formed integrally with the side surface stator core 24 so as to be adjacent to the magnetic pole tooth portion 30 by being connected by a bridge portion. Similarly, a side surface stator core 25 is also adjacent to the magnetic pole tooth portion 31. Then, the pole piece 40 is formed. Figure 1
1 (b), a magnetic pole piece 40 and a magnetic pole piece 41 are integrally formed by being connected by a bridge portion, and are supported so as to be sandwiched between the side surface stator cores 24 and 25.

11 (a) to 11 (c), a plate-shaped magnetic member is manufactured by press working, and at the same time, a required number of sheets are laminated by the crimping caulking 42 to be closely fixed. Note that the fixing may be performed by welding or the like in addition to the crimping. The magnetic pole tooth portions and the magnetic pole pieces formed on the side surface stator cores of the other coils have the same configuration, and are used in combination with the cylindrical rear surface stator core 21 (see FIG. 9) and the like.

FIG. 12 (a) is a side view in the axial half section of the state where the side stator core and the pole pieces are assembled and the coil 10 is wound, and the winding side of the coil 10 is injection-molded or the like. Another embodiment in which an insulating layer is formed of the resin 43 is shown. FIG. 12B shows still another embodiment in which the gap 43 between the side surface stator core 25 and the pole piece 40 is further filled with the resin 43. In addition, as shown in FIG. 12C, after the insulating layer is formed of resin by injection molding or the like and the coil 10 is wound as described above, the coils 10 are fixed to each other by the resin 45 by injection molding or the like. Another embodiment in which an insulating layer is formed on the outer peripheral side of is also shown.

According to the manufacturing method as described above, a highly accurate stator iron core can be easily manufactured at a low cost, a winding frame for coil winding is not required, and the stator iron core can be inexpensively and easily insulated. It can be carried out and can contribute to the improvement of productivity. At this time, instead of the conventional magnet wire having a circular cross-sectional shape, by using a magnet wire having a substantially rectangular cross-sectional shape, the gap between the wires can be reduced and the space factor of the winding can be improved. Therefore, the temperature rise of the coil can be suppressed, which can contribute to the efficiency improvement and downsizing of the induction motor. In addition,
12A to 12C, the fourth embodiment is shown.
8 has been described as an example, but it is obvious that the shape shown in FIG. 10 of the fifth embodiment is also applicable.

Embodiment 7. 13 and 14 show Embodiment 7 of the induction motor according to the present invention. In the seventh embodiment, a so-called dust core is used as a material for the stator core, in which iron powder is insulated one by one with an inorganic coating and compression molded.

FIG. 13 is a side view of an axial half-section showing the assembled state of the stator 20 and the frame 93 of the single-phase induction motor, and other components are omitted in the figure. Stator 2
Reference numeral 0 is composed of A-phase and B-phase coils 10 and 11, a rear stator core 50 on the outer peripheral side thereof, side stator cores 24 and 25 on both axial ends of the coils 10 and 11, and the like. .
The back stator iron core 50 is configured by using a dust core with the back stator iron cores 21 and 22 of the coils 10 and 11 being integrated, and the coils 10 and 11 and the side stator cores 24 and 25 are provided on the inner diameter side thereof. Etc. are configured to be sequentially stacked in the axial direction.

Arrow lines 51 and 52 in FIG.
11 schematically shows the flow of magnetic flux at a certain moment, and the magnetic flux moves three-dimensionally inside the rear stator core 50. For this reason, by using a dust core with large specific resistance and permeability values in all directions, the movement of the magnetic flux can be facilitated, the loss inside the iron core can be reduced, and the efficiency of the single-phase induction motor can be improved. Can contribute to.

Similarly, in the case of a three-phase induction motor, it is possible to reduce the loss by using a dust core for the back stator core. Further, in both single-phase and three-phase cases, the rear stator core of each phase is shared by one member, which facilitates assembly and contributes to improvement in productivity. Further, it is possible to remove the frame 93 and use the back stator core 50 as a part of the structure, which contributes to downsizing and cost reduction. Note that FIG.
As shown in (a), even when the rear stator core is divided for each phase, the powder magnetic core can be used by using the frame 93 and the like together. Further, in any case, by similarly using the dust core for the side surface stator cores 24, 25, etc., the loss inside the core can be further reduced.

FIG. 14 shows another embodiment in which one phase portion of the stator core shown in FIG. 10 of the fifth embodiment is taken out and constituted by a dust core. The stator core is divided into two parts by a dividing surface f in the direction perpendicular to the axis, each of which is composed of a powder magnetic core, and the coil 10 is formed into a ring shape in a separate step and is subjected to an appropriate insulation treatment, The side stator cores 24 and 25 are assembled. The stator cores of the other phases have the same structure.

According to the above-mentioned structure, since the magnetic flux can easily move three-dimensionally inside the stator core from the rear stator core 21 to the pole pieces 40, the loss inside the core can be further reduced. Therefore, it is possible to contribute to improving the efficiency of the single-phase / three-phase induction motor. Further, since the step of pressing the iron core is not required, the stator core can be easily manufactured at low cost, and the winding of each coil is facilitated, which contributes to improvement in productivity and cost reduction. it can. In addition,
The stator core bisected by the dividing surface f is appropriately fixed by press fitting, screwing or the like.

Embodiment 8. FIG. 15 shows Embodiment 8 of the induction motor according to the present invention. Embodiment 8
Then, in addition to the configuration of the above-described embodiment, the stator is skewed.

FIG. 15 is a view of the inner peripheral surface of the three-phase induction motor facing the basket-shaped rotor, with the rotor shaft being horizontal and the stator core being cut open. The U-phase magnetic pole tooth portion 30 and the magnetic pole piece 40 are connected to the magnetic pole tooth portion 31 adjacent to the circumferential direction and the magnetic pole piece 41 by a bridge portion E inclined by a skew angle. The W-phase magnetic pole teeth and the magnetic pole pieces are similarly configured.

In the above-mentioned structure, by optimizing the skew angle, the effect of the harmonic component of the gap magnetic flux can be reduced by the skew effect, so that the vibration and noise can be reduced and the three-phase induction can be achieved. The characteristics of the electric motor can be improved. The same effect can be obtained by skewing the cage rotor instead of skewing the stator. Also, in the case of a single-phase induction motor, the skew effect can be obtained by similarly performing the skew. In FIG. 15, the shape of the stator core shown in FIG. 10 of the fifth embodiment is shown as an example, but the shape of the stator core shown in FIG. 9 of the fifth embodiment is also applicable.

In the above-described first to eighth embodiments, the case where the number of poles of the single-phase / three-phase induction motor is four is applied to the present invention.
The induction motor according to the present invention is also effective for cases having other pole numbers. The induction motor according to the present invention can easily obtain a rotating machine having an optimum number of poles without being influenced by the inner diameter size of the stator and the number of slots unlike the conventional induction motor. Further, it is also possible to perform variable speed operation by driving an inverter or the like as in the conventional induction motor.

[0059]

As can be understood from the above description, according to the induction motor of the present invention, a plurality of coils are axially divided and wound in a ring shape, and the outer peripheral side of each coil and the shaft are wound. By providing stator cores that form a magnetic circuit on both ends in the direction, and by arranging the magnetic pole teeth on the inner peripheral side by a predetermined angle in the circumferential direction of the rotating shaft, and by stacking them in the axial direction. Since there is no part corresponding to the coil end, the amount of copper wire used in the coil can be reduced and copper loss can also be reduced, reducing the cost of the induction motor and reducing its size.
Weight reduction can be realized.

According to the induction motor of the next invention, the magnetic pole teeth formed on the stator core on both axial ends of the coil are provided with magnetic pole pieces made of a magnetic member, so that the coil is generated. Since the magnetic flux generated can be effectively utilized, the leakage magnetic flux is reduced, the efficiency of the induction motor is improved, and it can contribute to downsizing.

According to the induction motor of the next invention, since the leakage magnetic flux can be reduced and the gap magnetic flux density can be secured by providing the means for reducing the leakage of the magnetic flux of the stator, the induction motor can be secured. The characteristics of can be improved.

According to the induction motor of the next invention, by forming at least a part of the stator core by laminating and integrally using the plate-shaped magnetic member, a highly accurate stator core can be manufactured inexpensively and easily. Since it can be manufactured, it can greatly contribute to the improvement of productivity.

According to the induction motor of the next invention, since at least a part of the stator iron core is formed by using the dust core, the magnetic flux can easily move three-dimensionally, so that the loss inside the iron core is reduced. Can be reduced, which can contribute to improving the efficiency of the induction motor and reducing its size and weight.

According to the induction motor of the next invention, by skewing the stator or the rotor, it is possible to reduce the influence of the harmonic components of the gap magnetic flux. The characteristics of the electric motor can be improved.

[0065]

[Brief description of drawings]

1 is an axial half-section side view of a single-phase induction motor according to a first embodiment.

FIG. 2 is a connection diagram of the single-phase induction motor in the first embodiment.

FIG. 3 is a diagram showing a configuration of a magnetic pole tooth portion of a side surface stator core according to the first embodiment as seen through from a non-load side to a load side.

FIG. 4 is an axial half-section side view of a three-phase induction motor according to a second embodiment.

FIG. 5 is a connection diagram of a three-phase induction motor according to a second embodiment.

FIG. 6 is a diagram showing a configuration of a magnetic pole tooth portion of a side surface stator core according to the second embodiment as seen through from a non-load side to a load side.

FIG. 7 shows a configuration of a side surface stator core and magnetic pole pieces according to the third embodiment.

FIG. 8 shows a configuration of a side surface stator core and magnetic pole pieces according to the fourth embodiment.

FIG. 9A is a stator according to the fifth embodiment,
(B) is an axial half-section side view which shows the stator in other embodiment, respectively.

FIG. 10 is a side view in axial half section showing a stator according to still another embodiment of the fifth embodiment.

FIG. 11 is a diagram showing a configuration of a side surface stator iron core and a magnetic pole piece in Embodiment 6 as seen through from a non-load side to a load side.

FIG. 12 is an axial half-section side view showing a stator according to another embodiment of the sixth embodiment.

FIG. 13 is a side view in axial half section showing a stator according to the seventh embodiment.

FIG. 14 is a side view in axial half section showing a stator according to another embodiment of the seventh embodiment.

FIG. 15 is a diagram of an inner peripheral surface of a stator core according to the eighth embodiment.

16A and 16B show a conventional three-phase induction motor, in which FIG. 16A is a side view of a half cross section in the axial direction, and FIG.

[Explanation of symbols]

10-12 Stator coil, 13 Lead wire, 14
Capacitor, 15 single phase power supply, 16 three phase power supply, 2
0 stator, 21-23 back stator core, 24-29
Side stator core, 30 to 35 magnetic pole teeth, 40.4
1 pole piece, 42 caulking position of caulking, 43
45 resin, 44 gap between side stator core and magnetic pole piece, 50 integrated rear stator core using powder magnetic core, 51/52 magnetic flux flow, 80 cage rotor, 90 rotating shaft, 91 bearing Member, 92 bracket, 93 frame, 110 conventional coil,
120 Conventional stator core, a ・ b ・ c predetermined clearance, E bridge part, f dividing surface, h coil end length, s bridge part radial thickness

Claims (6)

[Claims] 1. An inner rotor type induction motor in which a stator provided with magnetic pole teeth facing each other with a predetermined air gap interposed between the rotor and an outer rotor is provided.
A plurality of coils are wound in a ring shape by being divided in the axial direction, and the coils are arranged so that the center of the ring of each coil and the center of the rotation axis substantially coincide with each other. , And stator iron cores that respectively constitute magnetic circuits are provided. Further, on the inner peripheral side of the stator core, the magnetic pole tooth portions are alternately formed at positions offset by an electrical angle π in the circumferential direction of the rotating shaft with the coil sandwiched therebetween. An induction motor having a structure in which tooth portions are shifted in the circumferential direction of a rotary shaft by a predetermined angle and are superposed in the axial direction. 2. The induction motor according to claim 1, wherein each magnetic pole tooth portion is provided with a magnetic pole piece formed of a magnetic member. 3. The stator is provided with means for reducing leakage of magnetic flux.
The induction motor according to any one of 1. 4. The induction motor according to claim 1, wherein at least a part of the stator core is laminated and formed by using a plate-shaped magnetic member. 5. The stator core according to claim 1, wherein at least a part of the stator core is formed using a so-called dust core (also referred to as an iron powder core; the same applies hereinafter). Induction motor described in. 6. The induction motor according to claim 1, wherein the stator or the rotor is skewed.