WO2003096519A2

WO2003096519A2 - Induction motor having stator windings divided it axial direction

Info

Publication number: WO2003096519A2
Application number: PCT/JP2003/004418
Authority: WO
Inventors: Yoshimitsu Okawa
Original assignee: Yoshimitsu Okawa
Priority date: 2002-05-12
Filing date: 2003-04-07
Publication date: 2003-11-20
Also published as: JP2003333811A

Description

Description Induction motor having a plurality of stator windings divided in the axial direction

The present invention relates to a single-phase induction motor such as a condenser motor operated by a single-phase power supply, a capacitor starting motor, a split-phase starting motor, and a three-phase induction motor operated by a three-phase power supply. Regarding wire system and stator core structure. Background art

Conventionally, as a motor of this type, for example, taking a three-phase induction motor as an example, a structure as shown in FIG. 16 is generally adopted. Fig. 16 (a) is a side view of the half-section in the axial direction.The stator core 120 has a coil 110 of U'V'W phase, and the winding development of Fig. 16 (b). After being wound by a dedicated machine as shown in (2), terminal treatments such as connection between windings and connection of lead wires are performed.

In the conventional three-phase induction motor as described above, the coils 110 of the U′V and W phases are distributed in the circumferential direction and are wound, so that they project from the axial end face of the stator core 120. The length h of the coil end increases and the amount of winding and the copper loss increase due to the coil end that does not contribute to the characteristics at all. There is a problem that it is difficult to reduce the size and weight and reduce the cost. Single-phase induction motors have the same problem because the main winding and the auxiliary winding are wound around the stator core in the circumferential direction.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has a small-sized, light-weight, high-efficiency, low-cost winding method and a stator core structure for an induction motor because there is no coil end. The purpose is to get. Disclosure of the invention

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 wound in a ring shape by being divided in an axial direction, and a center of a ring of each coil and a center of a rotary shaft are substantially set. The stator cores constituting the magnetic circuit are provided on the outer peripheral side and the axial both ends of each coil, respectively, and the magnetic pole teeth are provided on the inner peripheral side of the rotating shaft around the coil. Are formed alternately at positions shifted by an electrical angle from each other in the direction, and the magnetic pole teeth of each coil are axially overlapped with each other shifted by a predetermined angle in the circumferential direction of the rotating shaft. is there.

The induction motor according to the next invention further includes a pole piece made of a magnetic member at each magnetic pole tooth formed on the stator core at both ends in the axial direction of the coil.

The induction motor according to the next invention further includes means for reducing leakage of magnetic flux in the stator.

In the induction motor according to the next invention, at least a part of the stator core is formed by lamination and integration using a plate-shaped magnetic member. In the induction motor according to the next invention, at least a part of the stator core is formed using a so-called dust core (hereinafter, also referred to as iron powder core).

In the induction motor according to the next invention, the stator or the rotor is further skewed. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an axial half cross-sectional side view of a single-phase induction motor according to Embodiment 1.

FIG. 2 is a connection diagram of the single-phase induction motor according to the first embodiment. FIG. 3 is a view of the configuration of the magnetic pole teeth of the side stator core according to the first embodiment as seen through from the non-load side to the load side.

FIG. 4 is a half-sectional side view in the axial direction of the three-phase induction motor according to the second embodiment.

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

FIG. 6 is a view of the configuration of the magnetic pole teeth of the side stator core according to the second embodiment, seen from the non-load side to the load side.

FIG. 7 shows a configuration of a side stator core and a pole piece according to the third embodiment. FIG. 8 shows a configuration of a side stator core and a pole piece according to the fourth embodiment. FIG. 9 (a) is an axial half cross-sectional side view showing a stator according to the fifth embodiment, and FIG. 9 (b) is a stator according to another embodiment.

FIG. 10 is an axial half cross-sectional side view showing a stator according to still another embodiment of the fifth embodiment.

FIG. 11 is a diagram of the configuration of the side stator core and the pole piece according to the sixth embodiment, viewed from the non-load side to the load side.

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

FIG. 13 is an axial half cross-sectional side view showing the stator according to the seventh embodiment.

FIG. 14 is a half-sectional view in the axial direction showing a stator according to another embodiment of the seventh embodiment.

FIG. 15 is a diagram of the inner peripheral surface of the stator core according to the eighth embodiment. FIGS. 16A and 16B show a conventional three-phase induction motor. FIG. 16A is an axial half-sectional side view, and FIG. BEST MODE FOR CARRYING OUT THE INVENTION

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the accompanying drawings, an embodiment of an induction motor according to the present invention will be described below. The form will be described in detail.

Embodiment 1

FIGS. 1 to 3 show a first embodiment of an induction motor according to the present invention, which is a four-pole single-phase induction motor having two types of stator windings divided in an axial direction, which is applied to a capacitor motor. An example is shown below. Fig. 1 is an axial half cross-sectional side view showing the A-phase and B-phase coils 10 and 11, the lead wires 13, and the stator 20, the cage rotor 80, the rotating shaft 90, It is composed of a bearing member 91, a bracket 92, 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 Β-phase coils 10 and 11 are divided in the axial direction of the rotating shaft 90 so that the center of the ring of each coil 10 and 11 and the center of the rotating shaft 90 are approximately aligned. It is wound and subjected to appropriate insulation treatment, and is connected to a single-phase power supply 15 together with a capacitor 14 as shown in FIG. The stator 20 is composed of a coil 10 · 11, a back stator core 21-22 on the outer peripheral side thereof, and side stator cores 24 on both axial ends of each coil 10 · 11: The back stator core 21 of the Α phase and the side stator cores 24, 25 are magnetically connected to each other, and the inner circumference of the side stator cores 24, 25 Magnetic pole teeth 30 and 31 are formed on the sides. The B-phase stator has the same configuration, and has magnetic pole teeth 32 and 33 formed on the inner peripheral side.

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

FIGS. 3 (a) to 3 (d) show the configuration of the side stator cores 24 to 27 and the convex magnetic pole teeth 30 to 33 formed on the inner peripheral side. This is a view seen through from the non-load side to the load side (the shaft end side) of FIG. 1, and other components are omitted in the figure. Figure 3 (a) shows the side stator iron on the non-load side of the A-phase coil 10 The magnetic pole teeth 30 are formed at two locations so that the center in the circumferential direction is at the 12 o'clock and 6 o'clock positions of the watch. Fig. 3 (b) shows the side stator core 25 on the load side of the A-phase coil 10 and the magnetic pole tooth 31 has its center in the circumferential direction, and the side stator core 24 on the non-load side. It is formed at a position deviated by 7 ° in electrical angle from the center of the magnetic pole tooth portion 30 formed in FIG. As a result, through the back stator core 21 (omitted in the figure), the four magnetic poles are formed by the magnetic pole teeth portions 30 and 31 of the side stator core 24 and 25 with the A-phase coil 10 interposed. , Are formed alternately in the circumferential direction on the inner circumferential side.

Fig. 3 (c) shows the side stator iron core 26 on the non-load side of the B-phase coil 11 and the magnetic pole teeth 32 are centered in the circumferential direction on the anti-load side of the A-phase coil 10. It is configured so as to be shifted by an electrical angle of 7ΤΖ2 with respect to the center of the magnetic pole tooth portion 30 formed on the side stator core 24. Fig. 3 (d) shows the side stator core 27 on the load side of the B-phase coil 11 and the magnetic pole teeth 33 have the center in the circumferential direction of the side stator core 26 on the non-load side. It is formed at a position deviated by 7 ° in electrical angle from the center of the magnetic pole teeth 32 formed at the center. As a result, the magnetic pole teeth 30 and 31 formed by the main winding of the A-phase coil 10 were separated by 電気 / 2 in electrical angle through the back stator core 2 2 (omitted in the figure) to form a 4-pole coil. Magnetic poles are alternately formed in the circumferential direction on the inner peripheral side by the magnetic pole teeth 32, 33 of the side stator cores 26, 27 with the B-phase coil 11 interposed therebetween.

The stator 20 is composed of the above-mentioned A-phase and B-phase coils 10 and 11, the outer stator back stator cores 21 and 22, and the side stator cores 24 to 27 of each coil. It is configured such that they are overlapped in the axial direction while maintaining the above-described positional relationship.

In the present embodiment, for example, the magnetic flux generated by the A-phase coil 10 is applied to the back stator core 21 on the outer peripheral side → the side stator core 24 → the magnetic pole teeth portion 30 → the predetermined edge. Key gap Cage rotor 8 0 → Predetermined layer gap Magnetic pole teeth 3 1 → Side stator core 2 5 → Back stator core 2 1 4418

6

A change in magnetic flux generated in the axial direction by the ring-shaped coil 10 can be changed to a change in magnetic flux in the rotation direction by forming a magnetic path around the ring. B phase coil 1

The magnetic flux generated by 1 also shifts the magnetic pole teeth 32, 33 by 7 electrical degrees in the circumferential direction, corresponding to the phase difference caused by the capacitor 14 connected to the power supply. Therefore, the coil 10 0-

11 generates a two-phase rotation (movement) magnetic field around the rotation axis 90, and the cage rotor 80 can be driven to rotate by electromagnetic induction. Further, by changing the connection position of the capacitor 14 or the like, the rotating shaft 90 can be rotated in the reverse direction as in the case of the conventional condenser.

According to the above-described configuration, since there is no portion corresponding to the coil end, the amount of copper wire used in the coil can be reduced and the copper loss can be reduced, so that the efficiency of the single-phase induction motor can be improved, and the cost can be improved. Down, small size, and light weight can be realized. In addition, coil winding work and terminal processing can be simplified, and automation using a dedicated machine can be performed, contributing to an improvement in productivity.

Embodiment 2

FIGS. 4 to 6 show an example in which an induction motor according to a second embodiment of the present invention is applied to a four-pole three-phase induction motor having three types of stator windings divided in an axial direction. Fig. 4 is an axial half-section side view of the U * V'W phase coils 10 to 12 and lead wires 13, and stator 20, cage rotor 80, rotating shaft 90, It is composed of a bearing member 91, a bracket 92, a frame 93 and the like.

The U ■ V · W phase coils 10 to 12 are divided in the axial direction of the rotation axis 90, and the center of the ring of each coil 10 to 12 and the center of the rotation axis 90 are almost coincident. So that it is wound in the same direction with respect to the rotating shaft 90. Each coil is appropriately insulated, connected in a Y-shape, and connected to a three-phase power supply 16 by a lead wire 13 as shown in FIG. JP03 / 04418

7

The stator 20 is composed of coils 10 to 12, outer stator cores 21 to 23 on the outer peripheral side thereof, and side stator cores 24 to 29 at both axial ends of the coils 10 to 12, U The back stator core 21 of the phase and the side stator cores 24 and 25 are magnetically connected to each other, and further, on the inner peripheral side of the side stator cores 24 and 25, magnetic pole teeth 30 and 31 are respectively provided. Is formed. The V and W phases have the same configuration, and the magnetic pole teeth 32 to 35 are formed on the inner peripheral side.

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

6 (a) to 6 (f) show the configuration of the side stator cores 24 to 29 and the convex magnetic pole teeth 30 to 35 formed on the inner peripheral side of the cores. This is a view seen from the load side (the shaft end side) to the load side, and other components are omitted in the figure. FIG. 6 (a) shows the side stator core 24 on the non-load side of the U-phase coil 10, and the magnetic pole teeth 30 are arranged so that the center in the circumferential direction is at the 12 o'clock and 6 o'clock positions of the clock. It is formed in two places. Fig. 6 (b) shows a side stator core 25 on the load side of the U-phase coil 10, and the magnetic pole teeth 31 have a circumferential center formed on the side stator core 24 on the non-load side. The magnetic pole tooth portion 30 is formed at a position shifted by 7 electrical degrees with respect to the center. As a result, the four magnetic poles pass through the back stator core 21 (omitted in the figure), and the magnetic pole teeth 30, 3, 1 of the side stator cores 24, 25 sandwich the U-phase coil 10. Are formed alternately in the circumferential direction.

Fig. 6 (c) shows the side stator core 26 on the non-load side of the V-phase coil 11 and the magnetic pole teeth 32 are fixed at the center in the circumferential direction on the anti-load side of the ϋ-phase coil 10. The magnetic pole teeth 30 formed on the iron core 24 are shifted from the center of the magnetic pole teeth 30 by an electrical angle of 2ττ / 3. Fig. 6 (d) shows the side stator core 27 on the load side of the V-phase coil 11 and the magnetic pole teeth 33 are positioned in the circumferential direction. The core is formed at a position deviated by an electrical angle with respect to the center of the magnetic pole teeth 32 formed on the side stator core 26 on the non-load side. As a result, as in the case of the U-phase coil 10, the four magnetic poles pass through the back stator core 22 (omitted in the figure), and the side stator cores 26, 27 sandwich the V-phase coil 11 therebetween. The magnetic pole teeth 32, 33 are alternately formed in the inner circumferential direction.

FIG. 6 (e) shows the side stator core 28 on the non-load side of the W-phase coil 12, and the magnetic pole teeth 34 have the circumferential center at the non-load side of the U-phase coil 10. The electrical angle is shifted by 4 ττ / 3 with respect to the center of the magnetic pole teeth 30 formed on the side stator core 24. Fig. 6 (f) shows the side stator core 29 on the load side of the W-phase coil 12 and the magnetic pole teeth 35 have the center in the circumferential direction of the side stator core 28 on the non-load side. It is formed at a position deviated by 7 ° in electrical angle from the center of the magnetic pole teeth 34 formed in FIG. As a result, as in the case of the U and V phases, the four magnetic poles pass through the back stator core 23 (omitted in the figure), and the magnetic poles of the side stator cores 28 and 29 sandwich the W-phase coil 12 therebetween. The teeth 3 4 ■ 3 5 are alternately formed in the circumferential direction on the inner circumferential side.

The stator 20 includes the coils 10 to 12 of the above-described U and V'W phases, the outer stator cores 21 to 23 on the outer peripheral side, and the side stator cores 24 to 29 of each coil. Are arranged in the axial direction while maintaining the above positional relationship.

In this embodiment, for example, the magnetic flux generated by the U-phase coil 10 is applied to the outer stator side stator core 21 → side stator iron core 24 → magnetic pole teeth 30 → predetermined key. Key gap Cage rotor 8 0 Predetermined yair gap Magnetic pole teeth 3 1 Side stator core 2 5 → Back stator core 2 1 A magnetic path is formed, and it is generated in the axial direction by a ring-shaped coil 10. The change in the applied magnetic flux can be changed to a change in the magnetic flux in the rotation direction. The magnetic flux generated by the V'W phase coils 11 and 12 is also the same because the magnetic pole teeth 32 to 35 are shifted by 27 電気 / 3 in electrical angle in the circumferential direction according to the phase difference of the power supply. Action As a result, by supplying three-phase power to the coils 10 to 12, a three-phase rotating magnetic field around the rotating shaft 90 is generated, and the cage rotor is driven by electromagnetic induction. 80 can be driven to rotate. Furthermore, as in the case of the conventional three-phase induction motor, any two coils of the U, V, and W phases are switched to the power supply and connected in reverse to reverse the order of the phase rotation, and Since the direction of the torque acting on the shaped rotor 80 is reversed, the rotating shaft 90 can be rotated in the reverse direction. When the winding directions of the coils 10 to 12 are not the same, the magnetic pole teeth can be similarly actuated by shifting the magnetic pole tooth portion by 7 ° in electrical angle in the circumferential direction of the rotating shaft.

According to the configuration described above, since there is no portion corresponding to the coil end, it is possible to reduce the amount of copper wire used in the coil and reduce the copper loss, thereby contributing to an improvement in the efficiency of the three-phase induction motor. However, cost reduction and downsizing and weight reduction can be realized. In addition, since the number of coils for each phase is at least one for each coil, the coil winding work and terminal processing can be greatly simplified. 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 it is also possible to adopt Δ connection, Υ-Δ activation, and the like.

Embodiment 3.

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

Fig. 7 (a) and Fig. 7 (c) show the side stator cores 24 and 25 of the coil 10 (omitted in the figure) in the same manner as in the first or second embodiment. Alternatively, FIG. 7 (b) is a cross-sectional view taken along line AA of FIG. 7 (a), and FIG. 7 (d) is a view seen from FIG. 7 (c). ) Section B B is shown. The magnetic pole teeth 30 of the side stator iron core 24 on the non-load side have the same inner diameter as the magnetic pole teeth 30 in the direction of the opposite side stator core 25 on the load side. The configured pole piece 40 is provided on the inner diameter side of the coil 10. The magnetic pole teeth 31 of the side stator core 25 on the load side have the same inner diameter as the magnetic pole teeth 31 in the direction opposite to the pole piece 40 and in the direction of the side stator core 24 on the non-load side. It has a piece 41.

FIG. 7 (e) shows a state where the side stator cores 24 and 25 provided with the pole pieces 40 and 41 are assembled, and FIG. 7 (f) shows a cross section CC of FIG. 7 (e). The magnetic pole teeth 30 of the side stator core 24 and the magnetic pole pieces 40 are separated from the magnetic pole teeth 31 and the magnetic pole pieces 41 of the side stator iron core 25, which are circumferentially adjacent poles, by a predetermined gap a. The same pole piece is also formed at the pole teeth formed on the side stator core of the other coils.

According to the configuration described above, the magnetic flux generated in each coil by each pole piece can be effectively used, and the leakage magnetic flux is reduced, so that the efficiency of the induction motor is improved and contributes to downsizing. Can be.

Embodiment 4.

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

FIG. 8A shows a state in which the side stator cores 24 and 25 of the coil 10 (omitted in the figure) are assembled in the same manner as in FIG. The magnetic pole teeth 30 and the pole pieces 40 of the side stator iron core 24 are circumferentially adjacent to each other. On the inner peripheral side opposite to), they are connected by a bridge part Ε. FIG. 8B is an enlarged view of the bridge portion E in FIG. 8A, and s indicates the radial thickness of the bridge portion. Fig. 8 (c) is the same as Fig. 8 (a). The cross-section CC is shown, and the inner peripheral side facing the cage rotor 80 has a continuous cylindrical shape with no cutout. Similar bridge portions are formed on the pole teeth formed on the side stator cores of the other coils and on the pole pieces.

According to the above configuration, it is possible to improve the dimensional accuracy of the side stator core and the inner peripheral side of the pole piece, and by optimizing the dimensions and shape of the bridge portion, the gap flux due to the leakage magnetic flux can be improved. Since the strength of the pole piece can be ensured while suppressing the decrease in density, 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, a magnetic gap is provided between adjacent phases in the axial direction as a means for reducing the leakage of the magnetic flux of the stator core. is there.

Fig. 9 (a) is a half sectional side view in the axial direction showing the assembled state of the A-phase and B-phase stators of the single-phase induction motor and the frame 93, and other components are omitted in the figure. . The A-phase stator is composed of coil 10, side stator cores 24, 25 at both ends in the axial direction, and back stator core 21, and the B-phase stator is also connected to coil 11. Although it is composed of a stator core, 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. 9 (b) shows another embodiment. Compared to FIG. 9 (a), the back stator cores 21 and 22 are connected and integrally formed, but the A A predetermined gap b is provided as a magnetic gap between the phase stator core 25 and the phase B stator core 26.

FIG. 10 shows still another embodiment, in which the pole piece 40 formed on the A-phase side stator core 24 is an axial end face of the adjacent B-phase side stator core 25. Therefore, the B-phase side stator 03 04418

1 2

Similarly, the pole piece formed on the iron core 27 is configured to be shorter by a predetermined dimension c than the axial end face of the adjacent A-phase side stator core 26.

According to the above configuration, by optimizing the dimension b or c, it is possible to reduce the leakage of the magnetic flux to the adjacent phase and to secure the gap magnetic flux density, thereby improving the characteristics of the single-phase induction motor. Can be improved.

Similarly, in the case of a three-phase induction motor, by providing a gap b or c between the U and V phases and between the V and W phases, leakage of magnetic flux to adjacent phases can be reduced. The characteristics of the phase induction motor can be improved. In addition, in any of the single-phase and three-phase cases, the same effect can be obtained by forming the gap b or c using a non-magnetic member without forming a gap.

Embodiment 6

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

FIGS. 11 (a) and 11 (c) show the side stator cores 24 and 25 of the coil 10 (omitted in the figure) in the same manner as in the first or second embodiment. Alternatively, a view seen through from the non-load side to the load side (shaft end side) in Fig. 4 is shown. The side stator core 24 has a magnetic pole piece 41 adjacent to the magnetic pole teeth 30 and is integrally formed by being connected by a bridge portion. Similarly, the side stator core 25 has magnetic pole teeth 41. A pole piece 40 is formed adjacent to the part 31. Fig. 11 (b) shows the magnetic pole piece 40 and the magnetic pole piece 41 that are connected to each other by a bridge and are integrally formed, and are supported by being sandwiched between the side stator cores 24 and 25. Things.

For each of the parts shown in FIGS. 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 squeezing and tightening, and are tightly fixed. In addition, besides squeezing, fix by welding etc. You can also. The pole teeth and pole pieces formed on the side stator cores of the other coils have the same configuration, and are used in combination with the cylindrical back stator core 21 (see Fig. 9). .

Fig. 12 (a) is an axial half-section side view of the state where the above-described side stator core and the pole piece are assembled and the coil 10 is wound, and injection molding or the like is performed on the winding side of the coil 10. Another embodiment in which an insulating layer is formed of resin 43 is shown. FIG. 12 (b) shows still another embodiment in which the resin 43 is also filled in the gap 44 between the side stator core 25 and the pole piece 40. Further, FIG. 12 (c) shows that an insulating layer is formed of resin by injection molding or the like as described above, and the coil 10 is wound, and then the coils 10 are fixed to each other with resin 45 by injection molding or the like. In addition, another embodiment in which an insulating layer is formed on the outer peripheral side of the coil 10 will be described.

According to the above-described manufacturing method, a high-accuracy stator core can be easily manufactured at a low cost, and a winding frame for winding a coil is not required, and the stator core can be insulated at a low cost and easily. And contribute to the improvement of productivity. Also, at this time, by using a magnet wire having a substantially square cross section instead of a conventional magnet wire having a circular cross section, the gap between the wires can be reduced and the space factor of the winding can be improved. Therefore, it is possible to suppress a rise in the temperature of the coil, which can contribute to improving the efficiency and reducing the size of the induction motor. Although FIGS. 12 (a) to 12 (c) have been described with reference to the shape shown in FIG. 8 of the fourth embodiment as an example, the shape shown in FIG. 10 of the fifth embodiment may also be used. Obviously, it is adaptable. Embodiment 7

FIGS. 13 and 14 show Embodiment 7 of the induction motor according to the present invention. In the seventh embodiment, as the material of the stator core, a dust core obtained by insulating iron particles one by one with an inorganic coating or the like and performing compression molding or the like is used. FIG. 13 is a half cross-sectional side view in the axial direction showing an assembled state of the stator 20 and the frame 93 of the single-phase induction motor, and other components are omitted in the figure. The stator 20 is composed of A-phase and B-phase coils 10 and 11, a back stator core 5.0 on the outer peripheral side, and a side stator core on both axial ends of the coil 10 and 11. It consists of 24, 25, etc. The back stator core 50 is made of a dust core with the back stator cores 2 1 and 2 of the coils 10 and 11 integrated, and the coil 10 and 11 1 And the side stator cores 24, 25, etc. are sequentially stacked in the axial direction.

The arrow lines 5 1 and 5 2 in FIG. 13 schematically show the flow of magnetic flux at a certain moment due to the coils 10 and 11.In the back stator core 50, the magnetic flux is three-dimensional. Will move. Therefore, the use of a dust core having a large specific resistance and magnetic permeability in all directions facilitates the movement of magnetic flux, reduces the loss inside the iron core, and improves the efficiency of the single-phase induction motor. It can contribute to improvement.

Similarly, in the case of a three-phase induction motor, the loss can be reduced by using a dust core for the back stator core. In addition, in both the single-phase and three-phase, the back stator core of each phase is shared by one member, so that the assembly is facilitated and the productivity can be improved. Further, the frame 93 can be removed and the back stator core 50 can be used as a part of the structure, which can contribute to downsizing and cost reduction. As shown in FIG. 9 (a), even when the back stator core is divided for each phase, the dust core can be used by using the frame 93 or the like. In any case, by using a dust core similarly for the side 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 made of a dust core. The stator core is bisected by a dividing plane f in the direction perpendicular to the axis, and each is composed of a dust core. Orchid 18

The 15-layer 10 is formed in a ring shape in a separate process, subjected to an appropriate insulation treatment, and then assembled with the side-surface stator cores 24 and 25. The stator cores of the other phases are configured similarly.

According to the above-described configuration, since the magnetic flux can easily move three-dimensionally inside the stator core from the back stator core 21 to the pole piece 40, the loss inside the core can be further reduced. This can contribute to improving the efficiency of single-phase and three-phase induction motors. In addition, since the iron core pressing process is not required, the stator core can be easily manufactured at a low cost, and the winding of each coil becomes easy, which contributes to improvement in productivity and cost reduction. Can be. The stator core bisected by the dividing surface f is fixed as appropriate by press-fitting, screwing, or the like.

Embodiment 8

FIG. 15 shows an eighth embodiment of the induction motor according to the present invention. In the eighth embodiment, in addition to the configuration of the above-described embodiment, the stator is skewed.

Fig. 15 is a view of the three-phase induction motor with the stator core cut out with the rotation axis being horizontal and the inner peripheral surface facing the cage rotor. The U-phase magnetic pole tooth 30 and the magnetic pole piece 40 are connected to the magnetic pole tooth 31 and the magnetic pole piece 41 adjacent to each other in the circumferential direction at a skew angle and connected by a flange portion E. The adjacent V'W phase magnetic pole teeth and pole pieces are similarly configured.

In the above-described configuration, by optimizing the skew angle, the influence 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 motor can be reduced. Characteristics can be improved. Note that the same effect can be obtained by skewing the rotor in place of skewing the stator. Also, in the case of a single-phase induction motor, the skew The effect can be obtained. 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 can also be applied.

Embodiments 1 to 8 described above applied a case where the number of poles of a single-phase / three-phase induction motor is four to the present invention.However, the induction motor according to the present invention has a case where the number of poles is other than this. It is also effective. In the induction motor according to the present invention, a rotating machine having an optimum number of poles can be easily obtained without being affected by the inner diameter of the stator, the number of slots, and the like, unlike a conventional induction motor. Also, it is possible to perform variable speed operation by overnight drive or the like like a conventional induction motor. Industrial applicability

As can be understood from the above description, according to the induction motor of the present invention, a plurality of coils are wound in a ring shape on the stator in the axial direction, and the outer periphery and the both ends in the axial direction of each coil are respectively provided. A stator iron core that constitutes a magnetic circuit is provided, and the magnetic pole teeth are shifted by a predetermined angle in the circumferential direction of the rotating shaft on the inner peripheral side, and are superposed in the axial direction. Since there is no part to be used, the amount of copper wire used in the coil is reduced and the copper loss can be reduced, so that it is possible to reduce the cost, size, and weight of the induction motor.

According to the induction motor of the next invention, each magnetic pole tooth formed on the stator core at both ends in the axial direction of the coil is provided with a pole piece made of a magnetic member, so that the magnetic flux generated by the coil is reduced. Since it can be used effectively, the leakage flux is reduced and the efficiency of the induction motor is improved, which can contribute to downsizing.

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

According to the induction motor of the following invention, at least a part of the stator core is formed by laminating and integrating using a plate-shaped magnetic member, so that a high-precision stator core can be easily manufactured at low cost. Can greatly contribute to the improvement of productivity.

According to the induction motor of the next invention, at least the portion of the stator core is formed by using a dust core, so that the magnetic flux can easily move three-dimensionally, thereby reducing the loss inside the core. This contributes to improving the efficiency of the induction motor and reducing its size and weight.

According to the induction motor of the next invention, the influence of the harmonic component of the gap magnetic flux can be reduced by skewing the stator or the rotor. Characteristics can be improved.

Claims

8 Claims

1. In the case of an induction motor with an open-ended, single-mouth type, in which a stator having magnetic pole teeth opposed to each other via a predetermined gap is arranged outside the rotor, the stator is divided axially into a ring. A plurality of coils are wound in a shape, 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 a magnetic circuit is formed on each of the outer peripheral side and each axial end of each coil. A stator core will be provided. On the inner peripheral side of the stator core, the magnetic pole teeth are alternately formed at positions deviated by an electrical angle in the circumferential direction of the rotation axis with the coil interposed therebetween. An induction motor characterized in that its teeth are shifted by a predetermined angle in the circumferential direction of the rotating shaft and are superposed in the axial direction.

2. The induction motor according to claim 1, wherein each magnetic pole tooth portion includes a magnetic pole piece made of a magnetic member.

3. The induction motor according to claim 1, wherein the stator is provided with means for reducing magnetic flux leakage.

4. The method according to any one of claims 1 to 3, wherein at least a part of the stator core is formed integrally by lamination using a plate-shaped magnetic member.

5. The induction motor according to any one of claims 1 to 4, wherein at least a part of the stator core is formed using a so-called dust core (also referred to as iron powder core). .

6. The induction motor according to any one of claims 1 to 5, wherein the stator or the rotor is skewed.