JP2005130685A - Permanent magnet electric motor with annular stator coil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a low-cost, small, light-weight, highly-efficient permanent magnet electric motor with a winding system, in which coil ends do not exist and by the structures of the stator and the rotor. <P>SOLUTION: Coils of U-V-W phases are wound annularly, divided in the axial direction of the stator, and arranged, in such a way that the center of each coil ring is aligned with that of a rotating shaft. A stator core is provided that constitutes each magnetic circuit, at the outside circumferential side of each coil and both end sides of the axial direction. In the inner circumference, magnetic pole teeth provided with magnetic pole pieces are formed alternately at positions, displaced by an electrical angle π (rad) in the circumferential direction of the rotating shaft, with each coil being sandwiched in-between. Furthermore, non-magnetic members are arranged between the poles, and the magnetic pole teeth of each coil are stacked in the axial direction, so as to be displaced in the electrical angle 2π/3 (rad) in the circumferential direction of the rotating shaft. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

Detailed Description of the Invention

  The present invention relates to a permanent magnet type electric motor such as a brushless DC motor and an AC servo motor driven by a three-phase power source, and more particularly to a winding system, a stator core structure, and a permanent magnet type rotor structure.

  Conventionally, as this kind of permanent magnet type electric motor, for example, when an AC servo motor is taken as an example, a structure as shown in FIG. 15 is generally employed. FIG. 15A is an axial half sectional side view, and a U / V / W phase coil 110 is provided on the stator core 120, as shown in FIG. After being wound, the terminal treatment such as connection between windings and lead wire connection is performed. FIG. 15 (c) shows a so-called concentrated winding method mainly used for small-capacity models as viewed from the inner diameter side by opening the stator, and the coils 115 of each phase are directly wound around the stator tooth portion 125. ing.

Problems to be solved by the invention

  In the conventional permanent magnet type motor as described above, since the U, V, and W phase coils 110 are distributed in the circumferential direction for winding, the length of the coil end protruding from the axial end surface of the stator core 120 is long. Even if the concentrated winding method is used, the coil end h cannot be reduced to zero, and it is difficult to reduce the size, weight, efficiency, and cost by increasing the winding amount and copper loss. It was.

  The present invention has been made to solve the above-described problems. Since there is no coil end, the present invention is small, light, and highly efficient. Further, the end treatment of the winding is easy, and the cogging torque is reduced. An object of the present invention is to obtain a winding method of a permanent magnet type electric motor, a stator core structure, and a rotor structure.

Means for solving the problem

  In order to achieve the above-mentioned object, a permanent magnet type motor according to the present invention has a magnetic pole tooth on the outer side of a rotor provided with N and S poles alternately on the outer periphery so as to have the same polarity in the axial direction at an equal pitch. A stator with a section is arranged, and a U / V / W phase coil is wound around the stator in the axial direction, and the ring center of each coil and the center of the rotating shaft are approximately the same The stator cores that constitute the magnetic circuit are provided on the outer peripheral side and both axial ends of the U, V, and W phase coils, respectively, and the same pole as the permanent magnet type rotor is provided on the inner peripheral side. A plurality of magnetic pole tooth portions are alternately formed at positions shifted by π (rad) in the circumferential direction of the rotation axis across the coil, and each magnetic pole tooth portion is provided with a magnetic pole piece. A non-magnetic member is placed between the pole formed by the magnetic pole teeth and the magnetic pole teeth of each U / V / W phase coil are rotated. Shifting a predetermined angle in the circumferential direction of the one in which are configured as superimposed in the axial direction.

  In the permanent magnet type electric motor according to the next invention, a stator having magnetic pole teeth is arranged outside a rotor having alternating N and S poles so as to have the same polarity in the axial direction at an equal pitch on the outer periphery. Then, the stator is axially divided and wound with a U / V / W phase coil in a ring shape, and is arranged so that the center of the ring of each coil and the center of the rotating shaft substantially coincide with each other. A stator core that constitutes a magnetic circuit is provided on the outer peripheral side and both axial ends of each V / W phase coil, and magnetic pole teeth having the same number of poles as the permanent magnet type rotor are provided on the inner peripheral side. They are alternately formed at positions shifted by π (rad) in the circumferential direction of the rotating shaft across the coil, and each magnetic pole tooth part is provided with a magnetic pole piece, which is formed by the magnetic pole piece and the magnetic pole tooth part. The poles are connected by a bridge part, and the magnetic pole teeth of each U / V / W phase coil are not angled in the circumferential direction of the rotating shaft. To, those that are configured as superimposed in the axial direction.

  The permanent magnet type electric motor according to the next invention is divided in the axial direction of the stator and wound with a U / V / W phase coil in a ring shape, and the center of the ring of each coil and the center of the rotating shaft substantially coincide. The stator cores constituting the magnetic circuit are provided on the outer peripheral side and both axial ends of the U / V / W phase coils, respectively, and magnetic pole teeth with a predetermined number of poles are provided on the inner peripheral side. Are alternately formed at positions shifted by π (rad) in the circumferential direction of the rotating shaft across the coil, and each magnetic pole tooth part is provided with a magnetic pole piece, and the gap formed by the magnetic pole piece and the magnetic pole tooth part The non-magnetic member is arranged, and the magnetic pole tooth portions of the U, V, and W phase coils are overlapped so as to coincide with the axial direction of the rotating shaft. Permanent magnet type rotors that face each other through a predetermined air gap are NS poles having the same number of poles as the stator. Provided alternately at an equal pitch on the outer circumference, the center of the magnetic pole are those constituted by shifting a predetermined angle in the circumferential direction of the rotary shaft so as to correspond to the stator coils of U · V · W-phase.

  The permanent magnet type electric motor according to the next invention is divided in the axial direction of the stator and wound with a U / V / W phase coil in a ring shape, and the center of the ring of each coil and the center of the rotating shaft substantially coincide. The stator cores constituting the magnetic circuit are provided on the outer peripheral side and both axial ends of the U / V / W phase coils, respectively, and magnetic pole teeth with a predetermined number of poles are provided on the inner peripheral side. Are alternately formed at positions shifted by π (rad) in the circumferential direction of the rotating shaft across the coil, and each magnetic pole tooth part is provided with a magnetic pole piece, and the gap formed by the magnetic pole piece and the magnetic pole tooth part Are connected to each other at the bridge portion, and the magnetic pole tooth portions of the coils of the U, V, and W phases are superposed so as to coincide with the axial direction of the rotating shaft. Permanent magnet type rotors facing each other through a predetermined air gap have N · S of the same number of poles as the stator. Provided alternately at an equal pitch on the outer circumference and the center of the magnetic pole are those constituted by shifting a predetermined angle in the circumferential direction of the rotary shaft so as to correspond to the stator coils of U · V · W-phase.

  The permanent magnet type electric motor according to the next invention further includes means for reducing leakage of magnetic flux in the stator or the permanent magnet type rotor.

  In the permanent magnet type electric motor according to the next invention, at least a part of the stator core is laminated and integrated using a plate-like magnetic member.

  The permanent magnet type electric motor according to the next invention further comprises at least a part of the stator core using a dust core.

  The permanent magnet type electric motor according to the next invention is further formed such that the axial cross-sectional area of the pole piece gradually decreases from the pole tooth portion.

  In the permanent magnet type electric motor according to the next invention, the stator or the permanent magnet type rotor is further skewed.

  Embodiments of a permanent magnet type electric motor according to the present invention will be described below in detail with reference to the accompanying drawings.

Embodiment 1 FIG.
1 to 5 show an example in which the present invention is applied to a four-pole AC servo motor as a first embodiment of a permanent magnet type electric motor according to the present invention. U, V and W phase coils 10 to 12 and lead wires are shown. 13 and the stator 20, a permanent magnet type rotor 80, a rotating shaft 90 that supports the permanent magnet type rotor 80, a bearing member 91, a bracket 92, a frame 93, a detector 94, and the like.

  The coils 10 to 12 of the U, V, and W phases 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 substantially coincide with each other. On the other hand, after being wound in the same direction, subjected to appropriate insulation treatment and connected in a Y shape, the lead wire 13 is connected to the three-phase power supply unit 16 as shown in FIG.

  The stator 20 is composed of coils 10 to 12, rear stator cores 21 to 23 on the outer peripheral side thereof, and side surface stator cores 24 to 29 on both axial sides of the coils 10 to 12. The phase back stator core 21 and the side stator cores 24 and 25 are magnetically connected to each other, and magnetic pole teeth provided with pole pieces 40 and 41 on the inner peripheral side of the side stator cores 24 and 25, respectively. Portions 30 and 31 are formed respectively. The V / W-phase stator iron core is also configured in the same manner, and magnetic pole teeth 32 to 35 having magnetic pole pieces 42 to 45 are formed on the inner peripheral side.

  For example, the permanent magnet type rotor 80 is formed on the outer periphery of a rotor core 81 integrated with a rotating shaft 90 processed into a predetermined shape, with magnetic pole teeth 30 to 35 of U / V / W phase coils 10 to 12 and Permanent magnets 82 to 84 are disposed through the pole pieces 40 to 45 and a predetermined air gap, and are rotatably supported by the rotating shaft 90 and the bearing member 91. The permanent magnets 82 to 84 are composed of a neodymium rare earth magnet or the like, and both the residual magnetic flux and the holding force are large, and the magnetic energy product is extremely large. For this reason, even if the magnet area is reduced, the necessary gap magnetic flux can be secured, and the desired output can be obtained.

  3 (a) to 3 (f) show the configuration of the side stator cores 24 to 29, the convex magnetic pole tooth portions 30 to 35 and the magnetic pole pieces 40 to 45 formed on the inner peripheral side thereof. This is a view seen through from the opposite load side (detector side) to the load side (shaft end side), and other components are omitted in the figure. FIG. 3A shows a side stator core 24 on the opposite side of the U-phase coil 10, and the magnetic pole tooth portion 30 has its circumferential center aligned with the position of the match mark 36, It is formed in two places so as to be at the 6 o'clock position of the timepiece shifted by 2π (rad) in electrical angle. FIG. 3B shows the load-side side stator core 25 of the U-phase coil 10. The magnetic pole tooth portion 31 has a magnetic pole formed at the center in the circumferential direction on the anti-load-side side stator core 24. It is formed at a position shifted by π (rad) in electrical angle with respect to the center of the tooth portion 30. As a result, the four-pole magnetic poles pass through the back stator core 21 (not shown), and the magnetic pole teeth 30 and the magnetic pole pieces 40 and the magnetic pole teeth 31 and 31 of the side stator iron cores 24 and 25 sandwich the U-phase coil 10. The pieces 41 are alternately formed in the circumferential direction on the inner circumferential side.

  FIG. 3C shows a side stator core 26 on the side opposite to the load side of the V-phase coil 11, and the pole tooth portion 32 is centered in the circumferential direction on the side stator core on the side opposite to the load side of the U-phase coil 10. The electrical angle is shifted by 2π / 3 (rad) with respect to the center of the magnetic pole tooth portion 30 formed at 24. FIG. 3D shows a side stator core 27 on the load side of the V-phase coil 11, and the magnetic pole tooth portion 33 has a circumferential center formed on the side stator core 26 on the anti-load side. It is formed at a position shifted by π (rad) in electrical angle with respect to the center of the tooth portion 32. As a result, as in the case of the U-phase coil 10, the four-pole magnetic pole passes through the back stator core 22 (not shown), and the magnetic pole teeth 32 of the side stator cores 26 and 27 sandwich the V-phase coil 11. The magnetic pole pieces 42, the magnetic pole tooth portions 33 and the magnetic pole pieces 43 are alternately formed in the circumferential direction on the inner peripheral side.

  FIG. 3 (e) shows the side stator core 28 on the side opposite to the load side of the W-phase coil 12, and the pole tooth portion 34 is centered in the circumferential direction on the side stator core on the side opposite to the load side of the U-phase coil 10. The electrical angle is shifted by 4π / 3 (rad) with respect to the center of the magnetic pole tooth portion 30 formed at 24. FIG. 3 (f) is a load side side stator core 29 of the W-phase coil 12, and the magnetic pole tooth portion 35 has a magnetic pole formed in the side stator core 28 on the side opposite to the load in the circumferential direction. It is formed at a position shifted by π (rad) in electrical angle with respect to the center of the tooth portion 34. As a result, as in the case of the U / V phase, the 4-pole magnetic pole passes through the back stator core 23 (not shown), and the magnetic pole teeth 34 of the side stator cores 28 and 29 sandwich the W-phase coil 12. The magnetic pole pieces 44, the magnetic pole tooth portions 35, and the magnetic pole pieces 45 are alternately formed in the circumferential direction on the inner peripheral side.

  4 (a) to 4 (f) show the configuration of the side stator core, and FIGS. 4 (a) and 4 (c) show the side stator core 24 of the U-phase coil 10 (not shown). 25 is a view seen through the load side (shaft end side) from the non-load side in FIG. 1 in the same manner as described above, and FIG. 4B is a cross-sectional view along the line AA in FIG. ) Shows a cross section BB of FIG. A magnetic pole piece 40 having the same inner diameter as that of the magnetic pole tooth portion 30 in the direction of the load side side stator core 25 that is paired with the magnetic pole tooth portion 30 of the side stator core 24 on the opposite load side is coiled. 10 on the inner diameter side. A magnetic pole piece 41 having the same inner diameter as that of the magnetic pole tooth portion 31 is provided on the magnetic pole tooth portion 31 of the side stator core 25 on the load side in the direction opposite to the magnetic pole piece 40 and in the direction of the side stator core 24 on the antiload side. I have.

  FIG. 4E shows a state in which the side stator cores 24 and 25 having the pole pieces 40 and 41 are assembled, and FIG. 4F shows a cross section CC of FIG. The pole piece 40 formed on the side stator core 24 is configured to be shorter than the axial end face of the side stator core 25 by a predetermined dimension a, and the pole piece 41 formed on the side stator core 25 is the same. In addition, it is configured to be shorter than the axial end surface of the side stator core 24 by a predetermined dimension a. And between the poles formed by the magnetic pole tooth portion 30 and the magnetic pole piece 40 of the side stator core 24 and the magnetic pole tooth portion 31 and the magnetic pole piece 41 of the side stator iron core 25 serving as the adjacent pole in the circumferential direction, A non-magnetic member 46a having a width t is disposed, and is formed integrally with a ring-shaped non-magnetic member 46b on the coil winding side. The nonmagnetic members 46a and 46b may be made of a resin material in addition to a metal material such as an aluminum-based material. When the resin material is used, the insulating layer 46c on the coil winding side is also integrally molded, and the side surface stator is further formed. The gap 46d between the iron core and the pole piece can also be filled with resin. The stator cores of other coils are similarly configured.

  The stator 20 has the above-described positional relationship between the U, V, and W phase coils 10 to 12, the outer peripheral rear stator cores 21 to 23, and the side stator cores 24 to 29 of each coil. It is configured to be superposed in the axial direction while maintaining.

  FIG. 5 shows the permanent magnets 82 to 82 of the permanent magnet type rotor 80 facing the magnetic pole teeth 30 to 35 and the magnetic pole pieces 40 to 45 of the U / V / W phase coils 10 to 12 through a predetermined air gap. 84 shows a cross section in the direction perpendicular to the axis. In each case, four magnetic poles having the same number of poles as the stator are configured to have the same polarity in the axial direction at an equal pitch on the outer periphery.

  In this embodiment, for example, the magnetic flux generated by the U-phase coil 10 is generated from the outer side rear stator core 21 → side stator core 24 → magnetic pole tooth portion 30 and magnetic pole piece 40 → predetermined air gap → Permanent magnet 82 (S pole) → rotor core 81 → permanent magnet 82 (N pole) → predetermined air gap → magnetic pole tooth portion 31 and pole piece 41 → side stator core 25 → back stator core 21 magnetic path The change of the magnetic flux generated in the axial direction by interlinking with the ring-shaped coil 10 can be changed to the change of the magnetic flux in the rotation direction. The magnetic flux generated by the V / W phase coils 11 and 12 can be similarly actuated, and the magnetic pole tooth portions 32 and 34 corresponding to the phase difference of the power source are set to 2π / 3 (rad) in electrical direction in the circumferential direction. Since it is shifted, the permanent magnet type rotor 80 is driven to rotate in synchronization with this by supplying three-phase power to the coils 10 to 12 while determining the polarities of the permanent magnets 82 to 84 by the detector 94. It can be operated as an electric motor.

  According to the configuration as described above, since there is no portion corresponding to the coil end, the amount of copper wire used in the coil can be reduced to reduce copper loss, and the efficiency of the permanent magnet type motor can be improved and the cost can be reduced. In addition, further miniaturization can be realized. Further, since the number of coils in each phase is at least one each, the coil winding work and terminal processing can be greatly simplified, which can contribute to the improvement of productivity. Furthermore, it is possible to suppress the generation of vibration and noise by improving the rigidity of the magnetic pole piece with the nonmagnetic member between the poles, and a fitting portion is provided on the joint surface between the nonmagnetic member and the magnetic pole tooth part and the magnetic pole piece. The rigidity can be further improved by bonding or fixing. Further, by optimizing the dimensions a and t, the leakage of magnetic flux can be reduced and the gap magnetic flux density can be ensured, so that the characteristics of the permanent magnet type motor can be improved. In large-capacity models, it is possible to further suppress vibration by dividing the coils of each phase into a plurality of pieces and arranging them in the axial direction, and connecting them in series or in parallel appropriately for each phase. It can also be used as a ventilation duct between the iron cores of the divided coils. In addition, the arrangement order of the axial direction of the coil divided | segmented into plurality can be suitably determined in consideration of the characteristic of a permanent magnet type electric motor. Further, when the winding directions of the coils 10 to 12 are not the same, the corresponding magnetic pole teeth can be operated in the same manner as in the present embodiment by shifting the magnetic tooth portion by π (rad) in the circumferential direction of the rotating shaft by an electrical angle.

Embodiment 2. FIG.
FIG. 6 shows Embodiment 2 of the permanent magnet type electric motor according to the present invention. In the second embodiment, the width t = 0 of the nonmagnetic member 46a provided between the poles in the first embodiment described above, and the pole pieces and the pole tooth portions adjacent to each other in the circumferential direction, and the pole pieces are bridge portions. It is connected with.

  FIG. 6A shows a state in which the side stator cores 24 and 25 of the U-phase coil 10 (not shown) are assembled in the same manner as in FIG. 4E of the first embodiment. The magnetic pole tooth portion 30 and the magnetic pole piece 40 of the side stator core 24 are formed on the magnetic pole tooth portion 31 and the magnetic pole piece 41 of the side stator iron core 25 adjacent to each other in the circumferential direction to a permanent magnet type rotor 80 (not shown). They are connected by a bridge portion E on the opposite inner peripheral side. 6B is an enlarged view of the bridge portion E of FIG. 6A, and s indicates the thickness of the bridge portion E in the radial direction. FIG. 6C shows a cross-section CC of FIG. 6A, and the inner peripheral side facing the permanent magnet rotor 80 has a continuous cylindrical shape except for the portion of the dimension a. The stator cores of other coils are similarly configured.

  According to the configuration as described above, it is possible to improve the dimensional accuracy on the inner peripheral side of the side stator core and the pole piece, and furthermore, it is possible to avoid a steep fluctuation in the permeance of the magnetic circuit. It is possible to reduce the cogging torque of the electric motor and thus reduce the rotation unevenness. In addition, by optimizing the size and shape of the bridge portion, the rigidity of the pole piece can be improved while suppressing the decrease in the gap magnetic flux density due to the leakage magnetic flux, and the generation of vibration and noise can be reduced. .

Embodiment 3 FIG.
7 and 8 show Embodiment 3 of the permanent magnet type electric motor according to the present invention. The third embodiment is an example applied to a four-pole AC servo motor as in the first and second embodiments described above. Compared to the first embodiment, the magnetic pole tooth portions 30 to 35 and Although the configurations of the pole pieces 40 to 45 and the permanent magnet type rotor 80 are different, FIG. 1 generally shows a side view of the axial half-section of the third embodiment.

  FIG. 7 shows the configuration of the side stator cores 24 to 29 in the third embodiment, and the convex magnetic pole tooth portions 30 to 35 and the magnetic pole pieces 40 to 45 formed on the inner peripheral side thereof. Like FIG. 1, the figure seen through from the anti-load side (detector side) to the load side (shaft end side) of FIG. 1 is shown, and other components are omitted in the drawing. FIG. 7A shows the side stator cores 24, 26, and 28 on the non-load side of the U, V, and W phase coils 10 to 12 (not shown), and the magnetic poles including the pole pieces 40, 42, and 44. The teeth 30, 32, and 34 are centered in two locations so that their circumferential centers are at the 12 o'clock position of the watch according to the match mark 36 and the 6 o'clock position of the watch that is shifted by 2π (rad) in electrical angle. Is formed. FIG. 7B shows the side stator cores 25, 27, and 29 on the load side of the coils 10 to 12, and the magnetic pole tooth portions 31, 33, and 35 including the magnetic pole pieces 41, 43, and 45 are arranged around the periphery thereof. The center of the direction is formed at a position shifted by π (rad) in electrical angle with respect to the center of the magnetic pole tooth portions 30, 32, 34 formed on the side stator cores 24, 26, 28 of the anti-load cage. . As a result, the four-pole magnetic poles pass through the back stator core 21 (not shown), and the magnetic pole teeth 30 and the magnetic pole pieces 40 and the magnetic pole teeth 31 and 31 of the side stator iron cores 24 and 25 sandwich the U-phase coil 10. The pieces 41 are alternately formed in the circumferential direction on the inner circumferential side. Similarly, the four-pole magnetic poles pass through the rear stator core 22 (not shown), and the magnetic pole teeth 32 and the pole pieces 42 and the magnetic pole teeth 33 and the pole pieces of the side stator cores 26 and 27 with the V-phase coil 11 interposed therebetween. 43 are alternately formed in the circumferential direction on the inner circumferential side. Further, the four-pole magnetic poles pass through the back stator core 23 (not shown), and the magnetic pole teeth 34 and the pole pieces 44 and the magnetic pole teeth 35 and the pole pieces of the side stator cores 28 and 29 with the W-phase coil 12 interposed therebetween. 45 are alternately formed in the circumferential direction on the inner circumferential side.

    The magnetic pole tooth portion 30 and the magnetic pole piece 40 of the side stator core 24 of the U-phase coil 10 are side surfaces that are adjacent to each other in the circumferential direction, as in FIGS. 4 (a) to 4 (f) of the first embodiment. A non-magnetic member 46a having a predetermined width t is arranged between the poles formed by the magnetic pole tooth portion 31 and the magnetic pole piece 41 of the stator core 25, and the magnetic pole pieces 40 and 41 have a dimension a from the end face in the axial direction. The structure is short, and nonmagnetic members 46b to 46d are employed as necessary. The stator cores of other coils are similarly configured.

  The stator 20 includes the above-described U / V / W-phase coils 10 to 12, the outer side rear stator cores 21 to 23, and the side stator cores 24 to 29 of each coil as described above. The magnetic pole tooth portions are overlapped so as to coincide with the axial direction of the rotating shaft.

  FIGS. 8A to 8C show permanent magnets facing the magnetic pole tooth portions 30 to 35 and the magnetic pole pieces 40 to 45 of the U, V, and W phase coils 10 to 12 through a predetermined air gap. The cross section of the perpendicular direction of the permanent magnets 82-84 arrange | positioned at the outer periphery of the type | mold rotor 80 is shown. In each case, four magnetic poles having the same number of poles as the stator are formed on the outer periphery at an equal pitch. 8A shows the permanent magnet 82 facing the magnetic pole teeth 30 and 31 and the magnetic pole pieces 40 and 41 of the U-phase coil 10, and FIG. 8B shows the magnetic pole teeth 32 and 31 of the V-phase coil 11. 33 and the permanent magnet 83 facing the magnetic pole pieces 42 and 43, the circumferential center of the magnetic pole is deviated by 2π / 3 (rad) in electrical angle with respect to the circumferential center of the magnetic pole of the permanent magnet 82, Further, FIG. 8C shows the permanent magnet 84 facing the magnetic pole teeth 34 and 35 and the magnetic pole pieces 44 and 45 of the W-phase coil 12, and the center of the magnetic pole in the circumferential direction is the circumference of the magnetic pole of the permanent magnet 82. The electrical angle is shifted by 4π / 3 (rad) with respect to the center of the direction.

  In this embodiment as well, as in the first embodiment, the change in magnetic flux generated in the axial direction linked to the ring-shaped U / V / W-phase coils 10 to 12 is changed to the magnetic flux in the rotational direction. The permanent magnets 82 to 84 arranged in the permanent magnet type rotor 80 are shifted by 2π / 3 (rad) in electrical direction in the circumferential direction corresponding to the phase difference of the power source. It can act as a synchronous motor driven by a three-phase power source.

  As described above, even in this configuration, as in the first embodiment, there is no portion corresponding to the coil end. Therefore, the amount of copper wire used in the coil can be reduced, and the copper loss can be reduced. The efficiency of the electric motor is improved, cost reduction and further miniaturization can be realized, and furthermore, the mold of the stator core can be simplified, which can contribute to the improvement of productivity.

Embodiment 4 FIG.
In the fourth embodiment, the width t = 0 of the nonmagnetic member 46a provided between the poles in the above-described third embodiment, and the pole pieces and the pole tooth portions adjacent to each other in the circumferential direction, and the pole pieces are bridge portions. It is connected with.

  Therefore, the side stator core of the U-phase coil is configured in the same manner as in FIGS. 6A to 6C in the second embodiment described above, and the magnetic pole teeth 30 and the pole pieces 40 of the side stator core 24. Are connected to the magnetic pole tooth portion 31 and the magnetic pole piece 41 of the side stator core 25 adjacent to each other in the circumferential direction by a bridge portion E on the inner peripheral side facing the permanent magnet rotor 80, and other coils The stator iron core of is also configured in the same way.

  According to the above-described configuration, the mold of the stator core can be simplified, and further, by improving the dimensional accuracy on the inner peripheral side of the side stator core and the pole piece, the permeance of the magnetic circuit can be improved. By avoiding steep fluctuations, the cogging torque can be reduced, and as a result, rotation unevenness can be reduced.

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

  FIG. 9 is a half sectional side view in the axial direction showing the assembled state of the U / V / W-phase stator and the frame 93 of the permanent magnet type electric motor in which a = 0 in FIG. Parts are omitted in the figure. In FIG. 9A, the U-phase stator is composed of a coil 10, side stator cores 24 and 25 on both axial ends, and a rear stator core 21. Similarly, V and W-phase stators are also provided. The coils 11 and 12 and each stator core are composed of a U-phase stator core and a V-phase stator core that are adjacent to each other, and a V-phase stator core and a W-phase stator core. Is configured by providing a predetermined gap b as a magnetic gap.

  FIG. 9B shows another embodiment, and the rear stator cores 21, 22, and 23 are connected and formed integrally as compared with FIG. Between the side stator core 25 and the V-phase side stator core 26 and between the V-phase side stator core 27 and the W-phase side stator core 28 as a magnetic gap b. Is provided.

  According to the above configuration, by optimizing the dimension b, the leakage of magnetic flux to the adjacent phase can be reduced and the gap magnetic flux density can be secured, so that the characteristics of the permanent magnet type motor are improved. be able to. Further, for the stator shown in FIG. 9, the air gap b is similarly provided between the permanent magnets 82 to 84 that are adjacent to each other in the axial direction of the permanent magnet type rotor incorporated therein. The cost can be reduced while reducing the amount of expensive magnets used. In addition, the space | gap b of a stator iron core can be utilized as a ventilation duct, or it can use for drawer | drawing-out of a magnet wire. Further, the same effect can be obtained even if the non-magnetic member is used without forming the gap b of the stator core and the permanent magnet type rotor as a gap. It is obvious that the present invention can also be applied to cases other than a = 0 in FIG.

Embodiment 6 FIG.
FIG. 10 shows Embodiment 6 of the permanent magnet type electric 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-like magnetic member.

  FIG. 10 shows the side stator cores 24 and 25 of the U-phase coil 10 (not shown in the figure) as seen through the load side (shaft end side) from the non-load side in FIG. 1 as in the first embodiment. The figure is shown. A magnetic pole tooth portion 30 is formed on the side stator core 24 of FIG. 10A, and a magnetic pole piece 41 is adjacent to the magnetic pole tooth portion 30 on the side stator core 24 of FIG. They are connected by a bridge portion E and formed integrally. Similarly, in the side stator core 25 of FIG. 10 (d), a pole piece 40 adjacent to the magnetic pole tooth portion 31 is connected and formed integrally by a bridge portion E, and the side stator of FIG. 10 (e). A magnetic pole tooth portion 31 is formed on the iron core 25. In FIG. 10C, the pole piece 40 and the pole piece 41 are integrally formed by being connected by the bridge portion E, and are supported so as to be sandwiched between the side stator cores 24 and 25. .

  Each of the parts shown in FIGS. 10A to 10E is produced by pressing a plate-like magnetic member by pressing, and simultaneously laminating and fixing the required number of pieces by means of the nuke caulking 47. It can also be fixed by caulking pins, screwing, welding or the like. The stator cores of the other coils have the same structure, and after applying appropriate insulation treatment and winding the coils of each phase, they are shrink fitted into the cylindrical back stator core 21 (see FIG. 9) and press-fitted. Etc. Note that the back stator core 21 and the like can also be configured by being laminated and integrated using a plate-like magnetic member.

  According to the manufacturing method as described above, since a highly accurate stator core can be easily manufactured at low cost, the characteristics and productivity of the permanent magnet motor can be improved, and the cost can be reduced.

Embodiment 7 FIG.
11 and 12 show Embodiment 7 of the permanent magnet type electric motor according to the present invention. In the seventh embodiment, a part of the stator core is configured by using a so-called dust core in which iron powder is insulated one by one with an inorganic film and subjected to compression molding or the like.

  FIG. 11 is a half sectional side view in the axial direction showing the assembled state of the stator and the frame 93 of the permanent magnet type motor, and other components are omitted in the drawing. The stator is composed of U / V / W-phase coils 10 to 12, rear stator cores 21 to 23 on the outer peripheral side thereof, side stator cores 24 and 25 on both axial sides of the coils 10 to 12, and the like. ing. The rear stator cores 21 to 23 are each configured by using a dust core, and the coils 10 to 12 and the side stator cores 24 and 25 are arranged on the inner diameter side in the axial direction as in FIG. It is configured to be stacked in sequence.

  The arrow lines 51 to 53 in FIG. 11 schematically show the flow of magnetic flux at a certain moment by the coils 10 to 12, and the magnetic flux moves three-dimensionally inside the back stator cores 21 to 23. It will be. For this reason, by using a dust core that has a large specific resistance and permeability in all directions, it is easy to move the magnetic flux and reduce the loss inside the iron core, improving the efficiency of the permanent magnet motor. Can contribute. Similarly, dust cores can be used for the side stator cores 24 and 25.

  FIG. 12 (a) is a stator for one phase showing another embodiment composed of a dust core, and the stator core of the coil 10 is divided into two by a dividing plane f in the direction perpendicular to the axis. The coil 10 is formed in a ring shape in a separate process and subjected to appropriate insulation treatment, and then assembled with the side stator cores 24 and 25. The stator cores of other phases are configured in the same manner, and a fitting portion for connecting the stator cores to each other can be provided on the end surfaces of the stator cores adjacent in the axial direction.

  FIG. 12B shows a stator for one phase showing still another embodiment. The stator core of the coil 10 is divided into two by a dividing surface f in the direction perpendicular to the axis, and each is constituted by a dust core. The coil 10 is formed in a ring shape in a separate process and is subjected to appropriate insulation treatment, and is then mounted on the side stator core 24 side, and the side stator core is configured integrally with the back stator core 21. The 25 side and the dividing surface f are fitted and assembled.

  According to the configuration as described above, the magnetic flux can easily move three-dimensionally within the stator core from the back stator core 21 to the pole piece 40, so that the loss inside the core can be further reduced, and the permanent This can contribute to improving the efficiency of the magnet type electric motor. In addition, since some or all of the core pressing process is not required, the stator core can be easily manufactured at low cost, and the winding of each coil is facilitated, which improves productivity and reduces costs. Can contribute. Note that the stator core divided in two by the dividing surface f is appropriately fixed by press fitting, caulking pins, screwing, or the like.

  In FIG. 12, a U-shaped groove for drawing a magnet wire can be provided on the outer peripheral side of the side stator core 24 or the back stator core 21, and this U-shaped groove is used as the outer periphery of the side stator core of each coil. By providing the electrical angle at an electrical angle of 2π / 3 (rad) over the entire area, the magnet wire can be easily pulled out to the axial end face of the stator. At this time, one portion of the U-shaped groove can be used as the match mark 36, and the U-shaped groove not used for drawing the wire serves as a means for mutually connecting the stator cores adjacent to each other in the axial direction. This U-shaped groove can be replaced with a through hole. Note that the shape of the stator core shown in FIG. 12 can also be configured using a plate-like magnetic member.

Embodiment 8 FIG.
FIG. 13 shows Embodiment 8 of the permanent magnet type motor according to the present invention. In the eighth embodiment, the cross-sectional shape of the magnetic pole piece formed in the magnetic pole tooth portion is formed so as to be gradually reduced from the magnetic pole tooth portion.

  FIG. 13 shows a stator core for one phase, and shows an axial cross-sectional side view similar to FIG. 6C of the second embodiment. The magnetic poles are formed on the magnetic pole teeth 30 of the side stator core 24. The piece 40 is formed such that the axial cross-sectional area gradually decreases from the magnetic pole tooth portion 30 toward the side stator core 25, and the magnetic pole piece formed on the magnetic pole tooth portion 31 of the side stator core 25. The cross-sectional area 41 is also formed so as to gradually decrease from the magnetic pole tooth portion 31 in the direction of the side stator core 24. The stator cores of the other phases are similarly configured.

  According to the configuration as described above, the increase in the magnetic flux density of the magnetic pole teeth can be suppressed while securing the space for winding each coil, so that the loss inside the iron core is further reduced, and the efficiency of the permanent magnet type electric motor It can contribute to improvement.

Embodiment 9 FIG.
FIG. 14 shows Embodiment 9 of the permanent magnet type electric motor according to the present invention. In the ninth embodiment, in addition to the configuration of the above-described embodiment, the stator is skewed.

  FIG. 14 is a partial view of the inner peripheral surface facing the permanent magnet rotor, with the stator core being cut open with the rotation axis of the permanent magnet motor as the horizontal direction. The U-phase magnetic pole tooth portion 30 and the magnetic pole piece 40 are connected to the magnetic pole tooth portion 31 and the magnetic pole piece 41 adjacent to each other in the circumferential direction by a skew angle and connected by a bridge portion E, and V · W adjacent to each other in the axial direction. The respective magnetic pole teeth and pole pieces of the phase are similarly configured.

  In the above-described configuration, the effect of the harmonic component of the gap magnetic flux can be reduced by easily skewing the stator and optimizing the skew angle, so that vibration / noise and thus rotation unevenness can be reduced. And the characteristics of the permanent magnet type electric motor can be improved. Note that the same effect can be obtained by performing skew magnetization or the like on the permanent magnet arranged in the permanent magnet type rotor instead of skewing the stator. In FIG. 14, the shape of the stator core shown in FIG. 6 of the second embodiment is shown as an example, but the shape of the stator core shown in the other embodiments can be applied.

  In the first to ninth embodiments, the case where the number of poles of the permanent magnet type motor is four is applied to the present invention. However, the permanent magnet type motor according to the present invention is also effective for cases having other pole numbers. It is. The permanent magnet type electric motor according to the present invention can easily obtain an electric motor having the optimum number of poles without being influenced by the inner diameter size, the number of slots, etc. of the stator unlike the conventional permanent magnet type electric motor. In addition, the permanent magnet type electric motor according to the present invention is suitable for a built-in type because the coil portion is not exposed, and furthermore, since each coil is wound independently, varnish processing or the like is not required in low voltage models. It is environmentally friendly, can be easily insulated even in high-voltage models, and can be easily separated and reused when discarded. A small and low-cost motor can be obtained by adopting a single-phase motor structure with two types of ring-shaped stator coils.

The invention's effect

  As can be understood from the above description, according to the permanent magnet type motor according to the present invention, the stator is axially divided and wound with U / V / W phase coils in a ring shape, and the outer peripheral side of each coil. A stator core that forms a magnetic circuit is provided at both ends in the axial direction, and a magnetic pole tooth portion having a pole piece is shifted by a predetermined angle in the circumferential direction of the rotating shaft on the inner peripheral side, thereby nonmagnetic between the poles. By arranging the members so as to overlap each other in the axial direction, there is no portion corresponding to the coil end, so the amount of copper wire used in the coil can be reduced and the copper loss can be reduced. The efficiency of the type motor can be improved, and cost reduction and reduction in size and weight can be realized. In addition, coil winding work and terminal processing can be greatly simplified, which can contribute to improvement in productivity.

  According to the permanent magnet type motor according to the next invention, the magnetic pole tooth portion provided with the magnetic pole piece is shifted by a predetermined angle in the circumferential direction of the rotating shaft on the inner peripheral side of the stator core of each coil, and the gap between the poles at the bridge portion. By connecting and superposing them in the axial direction, the dimensional accuracy of the stator core is improved, and abrupt fluctuations in the permeance of the magnetic circuit can be avoided, reducing cogging torque and eventually rotating irregularities. Can be reduced.

  According to the permanent magnet type electric motor according to the next invention, the magnetic pole tooth portions of the coils in which the nonmagnetic members are arranged between the poles are superposed so as to coincide with the axial direction of the rotary shaft, and the permanent magnet type rotor The center of the magnetic pole of each stator coil is configured to be shifted by a predetermined angle in the circumferential direction of the rotating shaft for each opposing stator coil, so that the stator core mold can be simplified and the cost can be reduced. it can.

  According to the permanent magnet type electric motor according to the next invention, the magnetic pole tooth portions of the respective coils connected between the poles by the bridge portions are superposed so as to coincide with the axial direction of the rotary shaft, and the permanent magnet type rotor By configuring the center of the magnetic pole to be shifted by a predetermined angle in the circumferential direction of the rotating shaft for each opposing stator coil, the dimensional accuracy can be improved while simplifying the mold of the stator core.

  According to the permanent magnet type electric motor of the next invention, by providing the means for reducing the leakage of the magnetic flux of the stator or the permanent magnet type rotor, the leakage magnetic flux can be reduced and the gap magnetic flux density can be secured. Therefore, the characteristics of the permanent magnet type electric motor can be improved.

  According to the permanent magnet type electric motor according to the next invention, at least a part of the stator core is laminated and integrated using a plate-like magnetic member, so that a highly accurate stator core can be easily manufactured at low cost. Since it can be manufactured, it can contribute to the improvement of productivity.

  According to the permanent magnet type electric motor according to the next invention, at least a part of the stator core is configured by using the dust core, so that the magnetic flux can be easily moved three-dimensionally. This can be reduced, and can contribute to an improvement in efficiency and a reduction in size and weight of the permanent magnet type motor.

  According to the permanent magnet type electric motor according to the next invention, since the magnetic pole piece can be formed so that the cross-sectional shape of the magnetic pole piece is gradually reduced from the magnetic pole tooth portion, an increase in the magnetic flux density of the magnetic pole tooth portion can be suppressed. Can be further reduced, which can contribute to the improvement of the efficiency of the permanent magnet type motor.

  According to the permanent magnet type electric motor according to the next invention, the influence of the harmonic component of the gap magnetic flux can be reduced by skewing the stator or the permanent magnet type rotor. Can be small.

2 is a half sectional side view in the axial direction of the permanent magnet type electric motor according to Embodiment 1. FIG. FIG. 3 is a connection diagram of the permanent magnet type electric motor in the first embodiment. It is the figure which looked at the structure of the magnetic pole tooth part of the side stator iron core in Embodiment 1 through the load side from the non-load side. The structure of the side stator core and the pole piece in the first embodiment is shown. FIG. 3 is a cross-sectional view in the direction perpendicular to the axis of the permanent magnet type rotor according to the first embodiment. The structure of the side stator core and the pole piece in the second embodiment and the fourth embodiment is shown. It is the figure which looked at the structure of the magnetic pole tooth part of the side stator iron core in Embodiment 3 through the load side from the non-load side. FIG. 6 is a cross-sectional view in the direction perpendicular to the axis of a permanent magnet type rotor according to a third embodiment. (A) is the stator in Embodiment 5, (b) is an axial direction half cross section side view which respectively shows the stator in other Embodiment. It is the figure which looked at the structure of the side stator iron core and magnetic pole piece in Embodiment 6 through the load side from the non-load side. FIG. 16 is a side view in half of an axial direction showing a stator in a seventh embodiment. (A) is the stator in other embodiment of Embodiment 7, (b) is an axial direction half cross section side view which shows the stator in other embodiment. FIG. 20 is an axial cross-sectional side view showing a stator in an eighth embodiment. FIG. 25 is a partial view of the inner peripheral surface of the stator core in the ninth embodiment. The permanent magnet type electric motor of a prior art example is shown, (a) is an axial half cross-sectional side view, (b) is a winding development view, and (c) is a concentrated winding method.

Explanation of symbols

  10-12 Stator coil, 13 Lead wire, 16 Three-phase power supply unit, 20 Stator, 21-23 Rear stator core, 24-29 Side stator core, 30-35 Magnetic pole tooth part, 36 Match mark, 40- 45 magnetic pole pieces, 46a to 46d non-magnetic members, 47 crimping positions, 51 to 53 magnetic flux flows, 80 permanent magnet rotors, 81 rotor cores, 82 to 84 permanent magnets, 90 rotating shafts, 91 bearing members, 92 Bracket, 93 Frame, 94 Detector, 110/115 Conventional stator coil, 120 Conventional stator core, 125 Conventional stator tooth, a / b Predetermined gap, E Bridge part, f Dividing surface, h Length of coil end, s thickness in the radial direction of the bridge part, t width of non-magnetic member

Claims (9)

It has a permanent magnet type rotor that is driven by a three-phase power source and has N and S poles alternately arranged at the same pitch in the axial direction on the outer periphery. In an inner rotor type permanent magnet electric motor in which a stator having magnetic pole teeth facing each other via an air gap is arranged, a U / V / W phase coil is formed in a ring shape by dividing the stator in the axial direction. Winding is arranged so that the center of the ring of each coil and the center of the rotating shaft are substantially coincident with each other, and a stator core constituting a magnetic circuit is provided on each of the outer peripheral side and each axial end of each coil. Then, on the inner peripheral side of the stator core, the magnetic pole tooth portions having the same number of poles as the permanent magnet type rotor are shifted by π (rad) in electrical direction in the circumferential direction of the rotating shaft across the coil. Each magnetic pole tooth part is provided with a magnetic pole piece, a non-magnetic member is disposed between the magnetic pole piece and the pole formed by the magnetic pole tooth part, A permanent magnet electric motor characterized in that the magnetic pole teeth are shifted by a predetermined angle in the circumferential direction of the rotating shaft and overlapped in the axial direction. It has a permanent magnet type rotor that is driven by a three-phase power source and has N and S poles alternately arranged at the same pitch in the axial direction on the outer periphery. In an inner rotor type permanent magnet electric motor in which a stator having magnetic pole teeth facing each other via an air gap is arranged, a U / V / W phase coil is formed in a ring shape by dividing the stator in the axial direction. Winding is arranged so that the center of the ring of each coil and the center of the rotating shaft are substantially coincident with each other, and a stator core constituting a magnetic circuit is provided on each of the outer peripheral side and each axial end of each coil. Then, on the inner peripheral side of the stator core, the magnetic pole tooth portions having the same number of poles as the permanent magnet type rotor are shifted by π (rad) in electrical direction in the circumferential direction of the rotating shaft across the coil. The magnetic pole teeth of each coil are alternately formed at positions, and each magnetic pole tooth portion is provided with a magnetic pole piece, and the pole formed by the magnetic pole piece and the magnetic pole tooth portion is connected by a bridge portion. A permanent magnet type electric motor characterized in that the portion is shifted in the circumferential direction of the rotating shaft by a predetermined angle and overlapped in the axial direction. In an inner rotor type permanent magnet type motor driven by a three-phase power source, a U / V / W phase coil is wound in a ring shape divided in the axial direction of the stator, and the center of the ring of each coil is Are arranged so that the centers of the rotary shafts substantially coincide with each other, and stator cores constituting magnetic circuits are provided on the outer peripheral side and the axially opposite ends of each coil. And on the inner peripheral side of the stator core, magnetic pole tooth portions having a predetermined number of poles are alternately formed at positions shifted by π (rad) in electrical direction in the circumferential direction of the rotation shaft across the coil, Each magnetic pole tooth part is provided with a magnetic pole piece, a nonmagnetic member is arranged between the magnetic pole piece and the pole formed by the magnetic pole tooth part, and the magnetic pole tooth part of each coil is arranged in the axial direction of the rotation axis. Overlays to match. Further, the permanent magnet type rotor facing the inner side of the magnetic pole tooth portion with a predetermined air gap alternately includes N and S poles having the same number of poles as the stator on the outer periphery at equal pitches. The permanent magnet type electric motor is characterized in that the center in the circumferential direction of the magnetic pole is shifted by a predetermined angle in the circumferential direction of the rotary shaft in correspondence with the stator coil of the U / V / W phase. In an inner rotor type permanent magnet type motor driven by a three-phase power source, a U / V / W phase coil is wound in a ring shape divided in the axial direction of the stator, and the center of the ring of each coil is Are arranged so that the centers of the rotary shafts substantially coincide with each other, and stator cores constituting magnetic circuits are provided on the outer peripheral side and the axially opposite ends of each coil. And on the inner peripheral side of the stator core, magnetic pole tooth portions having a predetermined number of poles are alternately formed at positions shifted by π (rad) in electrical direction in the circumferential direction of the rotation shaft across the coil, Each magnetic pole tooth portion includes a magnetic pole piece, and the pole formed by the magnetic pole piece and the magnetic pole tooth portion is connected by a bridge portion, and the magnetic pole tooth portion of each coil coincides with the axial direction of the rotating shaft. In this way, they are overlapped. Further, the permanent magnet type rotor facing the inner side of the magnetic pole tooth portion with a predetermined air gap alternately includes N and S poles having the same number of poles as the stator on the outer periphery at equal pitches. The permanent magnet type electric motor is characterized in that the center in the circumferential direction of the magnetic pole is shifted by a predetermined angle in the circumferential direction of the rotary shaft in correspondence with the stator coil of the U / V / W phase. The permanent magnet type electric motor according to any one of claims 1 to 4, wherein the stator or the permanent magnet type rotor is provided with means for reducing leakage of magnetic flux. The permanent magnet type electric motor according to any one of claims 1 to 5, wherein at least a part of the stator core is laminated and integrated using a plate-like magnetic member. The permanent magnet according to any one of claims 1 to 6, wherein at least a part of the stator iron core is configured by using a so-called dust core (also referred to as an iron core). Type electric motor. The permanent magnet type motor according to any one of claims 1 to 7, wherein a cross-sectional area in the axial direction of the magnetic pole piece is formed so as to be gradually reduced from the magnetic pole tooth portion. The permanent magnet type electric motor according to any one of claims 1 to 8, wherein the stator or the permanent magnet type rotor is skewed.

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