JP7196617B2 - Stator device for polyphase motor and polyphase motor provided with the same - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator device for a polyphase motor in which a plurality of stators having axially extending magnetic poles such as claw-shaped magnetic poles are laminated, and a polyphase motor including the same.

2. Description of the Related Art Conventionally, an electric motor having a motor stator assembly formed by laminating a plurality of claw-pole stators having claw-shaped magnetic poles extending in the axial direction has been disclosed (see, for example, Patent Document 1).

JP 2014-233189 A

However, in the above-mentioned conventional electric motor, the motor-stator assembly is constructed by stacking three stators each having a claw pole structure. Therefore, the magnetic resistance is unbalanced between the stators at both ends in the stacking direction and the intermediate stator sandwiched between them. That is, the middle stator can pass magnetic flux through a part of the stator at both ends as a magnetic path at both ends where the stator is sandwiched. does not exist. Therefore, the magnetic resistance of the middle stator is lower than that of the stators at both ends, and the magnetic resistances of both ends and the middle are unbalanced. As a result, torque ripple occurs.

Therefore, the present invention has been made by paying attention to such unsolved problems of the prior art, and is a stator device in which three or more stators are laminated. An object of the present invention is to provide a stator device for a polyphase motor suitable for reducing unbalanced magnetic resistance and a polyphase motor having the same.

In order to achieve the above object, a stator device for a polyphase motor according to a first aspect of the present invention is made of a material having non-directional magnetic properties, and has a radially inner or outer peripheral portion along the circumferential direction. an annular stator core having a plurality of magnetic pole portions arranged side by side and each extending in an axial direction; At least N (N is a natural number equal to or greater than 3) stators each including an excitation coil. The N or more stators are stacked with their respective centers aligned, and at both ends in the stacking direction, magnetic circuits for expanding the magnetic circuits corresponding to the respective phases of the stators at both ends are provided. An extension member is provided.

In order to achieve the above object, a polyphase motor according to a second aspect of the present invention includes: a stator device for a polyphase motor according to the first aspect; an annular rotor yoke arranged facing each of the plurality of magnetic pole portions of the N or more stators with a predetermined gap in the radial direction, and the plurality of magnetic pole portions among the inner and outer peripheral portions of the rotor yoke; and N magnet portions in which different magnetic poles are arranged alternately and repeatedly along the circumferential direction and opposed to the magnetic pole portions of each stator with a predetermined gap in the radial direction, respectively, provided on the side facing the a rotor;

As described above, in the stator device for a polyphase motor according to the present invention, since the magnetic circuit extension members are provided at both ends in the lamination direction, the magnetic circuit including the stators at both ends is formed. Expandable. This makes it possible to reduce the magnetic resistance of the magnetic circuits corresponding to the respective phases at both ends, as compared with the case where the magnetic circuit expansion member is not provided. As a result, it is possible to reduce the imbalance of reluctance between the intermediate phase magnetic circuit configured including the intermediate stator and the magnetic circuits of the both end phases. In addition, with a polyphase motor equipped with this stator device, it is possible to reduce the torque ripple during driving by reducing the imbalance of the magnetic resistance. can be provided.

1 is a perspective view of a polyphase motor according to a first embodiment of the invention; FIG. 1 is a perspective view of a polyphase motor according to a first embodiment of the invention; FIG. The figure shows a state in which the side frame is removed. 1 is a side view of a polyphase motor according to a first embodiment of the invention; FIG. The figure shows a state in which the side frame is removed. 1 is a perspective view of a stator device according to a first embodiment of the invention; FIG. FIG. 3 is a perspective view showing a state in which a magnetic circuit expansion member is removed from the stator device according to the first embodiment of the present invention; 1 is a schematic cross-sectional view taken along an axis of a stator device according to a first embodiment of the present invention; FIG. It is a perspective view of an exciting coil. 1 is a perspective view of a magnetic circuit expansion member according to a first embodiment of the present invention; FIG. (a) is a schematic partial cross-sectional view showing an example of the flow of magnetic flux in each phase when no magnetic circuit expansion member is provided, and (b) is a schematic partial cross-sectional view of each phase when a magnetic circuit expansion member is provided; is a schematic partial cross-sectional view showing an example of the flow of magnetic flux. FIG. 7 is a schematic cross-sectional view of the stator device according to the second embodiment of the invention, taken along the axis;

Next, first and second embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings also include schematics, and the vertical and horizontal dimensions and scales of members and portions may differ from the actual ones. Therefore, there are cases where specific dimensions and scales should be determined with reference to the following description. In addition, it is a matter of course that there are portions with different dimensional relationships and ratios between the drawings.

Further, the first and second embodiments shown below are examples of apparatuses and methods for embodying the technical idea of the present invention. The shape, structure, arrangement, etc. are not specified as follows. Various modifications can be made to the technical idea of the present invention within the technical scope defined by the claims.

[First embodiment]
〔composition〕
First, the configuration of a polyphase motor 1 provided with a polyphase motor stator device 2 (hereinafter simply referred to as "stator device 2") according to a first embodiment of the present invention will be described.
As shown in FIGS. 1 to 3 and 6, the multiphase motor 1 includes a stator device 2, a rotor device 3, a side frame 4, a top frame 5A, a bottom frame 5B, a rotating shaft 6, It includes a reduction gear 7, a stator fixing member 8, and bearings 9A and 9B.

The side frame 4 has a cylindrical shape, and has a flange 4a formed at one axial end and a flange 4b formed at the other axial end. In addition, the side surface is provided with a lead portion 4c formed by a substantially rectangular notch elongated in the axial direction for drawing out each end portion 24b (described later) of the three exciting coils 24 to the outside. Furthermore, the flanges 4a and 4b are provided with four bolt holes which are formed at equal intervals in the circumferential direction and penetrate axially. In addition, the outer shape of the flanges 4a and 4b is substantially octagonal in plan view from the axial direction.

The top frame 5A is composed of a substantially octagonal plate-like member having the same external shape as the flange 4a when viewed from the axial direction. A boss portion 50A having a common shaft hole is provided. In addition, a cylindrical cover portion 51A configured to cover the reduction gear 7 is provided at the center of the plate surface on the other end side in the axial direction. Furthermore, four bolt holes for fixing are provided at the outer diameter side end of the top frame 5A, which are formed at equal intervals in the circumferential direction and axially through the plate surface. The top frame 5A abuts against the end surface of the flange 4a on one axial end side of the side frame 4 with the bolt holes aligned, and is fixed to the side frame 4 with bolts 110. As shown in FIG.
Hereinafter, the side of the polyphase motor 1 on which the top frame 5A is provided will be referred to as the "top side".

The bottom frame 5B is composed of a substantially octagonal plate-like member having the same external shape as the flange 4b when viewed from the axial direction. An annular boss portion 50B having an axial hole for insertion is provided. Around the shaft hole of the boss portion 50B, four bolt holes for fixing the stator device 2 are provided at equal intervals in the circumferential direction and penetrate through the plate surface. An annular boss portion 51B having the same outer diameter as the boss portion 50B is provided at the center of the plate surface on the top side of the bottom frame 5B. Furthermore, four bolt holes for fixing are provided at the outer diameter side end of the bottom frame 5B, which are formed at equal intervals in the circumferential direction and axially penetrate the plate surface. The bottom frame 5B abuts against the end face of the flange 4b on the other end side of the side frame 4 with the bolt holes aligned, and is fixed to the side frame 4 with bolts 110. As shown in FIG.
Hereinafter, the side of the polyphase motor 1 on which the bottom frame 5B is provided is referred to as the "bottom side".

The rotating shaft 6 has a substantially central portion in the axial direction fixed to the inner peripheral portion of the rotor device 3 arranged inside the stator device 2 , and the portion closer to the top than the stator device 2 is the reduction gear 7 . It protrudes to the outside through the inner peripheral portion and the shaft hole of the top frame 5A. On the other hand, the portion on the bottom side of the stator device 2 protrudes outside through the inner peripheral portion of the stator fixing member 8 and the shaft hole of the bottom frame 5B. Further, the top side of the rotary shaft 6 is rotatably supported by the inner peripheral portion of the shaft hole of the top frame 5A via a bearing 9A, and the bottom side of the rotating shaft 6 is supported by the inner peripheral portion of the shaft hole of the bottom frame 5B with a bearing 9B. It is rotatably supported through.

The reduction gear 7 is arranged inside the cover portion 51A of the top frame 5A, and is fixed to the top frame 5A with bolts while the rotary shaft 6 is inserted into a shaft hole formed in an internal gear (not shown). It is Although not shown, the reduction gear 7 is composed of, for example, a spur gear, a sun gear, a planetary gear, a worm gear, etc., and reduces the rotational speed of the rotary shaft 6 based on a set reduction ratio.

The stator fixing member 8 has an annular shape, and its top end is fixed to the bottom end of the stator device 2 concentrically with the stator device 2 . Four bolt holes (not shown) for fixing the stator device 2 are provided at equal intervals in the circumferential direction at the bottom side end of the stator fixing member 8 . That is, the stator device 2 is fixed to the bottom frame 5B by bolts 130 via the stator fixing member 8. As shown in FIG.

As shown in FIGS. 1 to 6, the stator device 2 includes a U-phase stator 21U, a V-phase stator 21V, and a W-phase stator 21W, which are axially laminated, and axially outside the U-phase stator 21U and the W-phase stator 21W. and magnetic circuit extension members 23A and 23B provided on the end faces of the magnetic circuit.

U-phase stator 21U includes U-phase stator core 210U and U-phase excitation coil 24U, V-phase stator 21V includes V-phase stator core 210V and V-phase excitation coil 24V, and W-phase stator 21W includes W-phase. It has a stator core 210V and a W-phase excitation coil 24W.

In the first embodiment, the U-phase stator 21U, the V-phase stator 21V, and the W-phase stator 21W all have the same configuration. called. Similarly, U-phase stator core 210U, V-phase stator core 210V, and W-phase stator core 210W are also simply referred to as "stator core 210" when there is no need to distinguish them. The U-phase excitation coil 24U, the V-phase excitation coil 24V, and the W-phase excitation coil 24W are also simply referred to as "excitation coils 24" when there is no need to distinguish them.

In the first embodiment, the stator core 210 of each phase stator is composed of a molded body (hereinafter referred to as "powder core") formed by compressing soft magnetic powder whose surface is electrically insulated. Here, as the magnetic powder, for example, a powder of pure iron, an iron-based alloy, or the like, which is excellent in plastic deformation under pressure, is used. Since the dust core made of powder has magnetic isotropy, there is no restriction on the direction in which the magnetic path is formed. That is, the powder core has non-directional magnetic properties.

The stator core 210 includes an annular first stator yoke portion 210A and eight claw-shaped first magnetic pole portions 212A provided on the inner peripheral portion of the first stator yoke portion 210A. In addition, an annular second stator yoke portion 210B and eight claw-shaped second magnetic pole portions 212B provided on the inner peripheral portion of the second stator yoke portion 210B are provided.

Specifically, the first stator yoke portion 210A includes a cylindrical main body portion 2100A and a circular plate-like band projecting radially inwardly from one axial end (top side in FIG. 5) of the main body portion 2100A. 2101A.

Each of the first magnetic pole portions 212A includes a claw bottom portion 2120A projecting from the inner diameter portion of the belt portion 2101A of the first stator yoke portion 210A toward the center in a substantially trapezoidal plate-like shape in a plan view, and a shaft extending from the claw bottom portion 2120A. and a claw portion 2121A having a substantially semi-truncated cone shape erected toward the other side of the direction (bottom side in FIG. 5). Further, the claw portion 2121A of each first magnetic pole portion 212A is erected with the substantially trapezoidal cut surface 2122A directed toward the inner diameter side. Hereinafter, this substantially trapezoidal cut surface 2122A is referred to as a "magnetic pole surface 2122A".

In addition, on the outer peripheral portion of the first stator yoke portion 210A, three grooves for drawing out the exciting coil 24 are provided at regular intervals in the circumferential direction, and cutout portions are respectively formed in the deep portions of these three grooves. and are provided.

The second stator yoke portion 210B includes a cylindrical main body portion 2100B and a circular belt-like plate-like belt portion 2101B (illustrated) projecting radially inwardly from one axial end (bottom side in FIG. 5) of the main body portion 2100B. abbreviated).

Each of the second magnetic pole portions 212B includes a claw bottom portion 2120B projecting from the inner diameter portion of the band portion 2101B of the second stator yoke portion 210B toward the center in a substantially trapezoidal and plate-like shape in plan view, and a shaft extending from the claw bottom portion 2120B. and a claw portion 2121B having a substantially semi-truncated cone shape erected toward the other side of the direction (the top side in FIG. 5). Further, the claw portion 2121B of each second magnetic pole portion 212B is erected with a substantially trapezoidal cut surface (magnetic pole surface) 2122B directed toward the inner diameter side.

Here, the second stator yoke portion 210B has a shape similar to that of the first stator yoke portion 210A, except that the positions of grooves and notches formed in the outer peripheral portion are different from those of the first stator yoke portion 210A. have.

The stator core 210 is configured such that the first stator yoke portion 210A and the second stator yoke portion 210B are concentrically arranged so that the first magnetic pole portion 212A side and the second magnetic pole portion 212B side face each other in the axial direction. The excitation coil 24 is sandwiched between the band portions 2101A and 2101B at opposing positions, and the first magnetic pole portions 212A and 212B are meshed so that they are alternately arranged along the circumferential direction. .

Specifically, in the first embodiment, the first magnetic pole portion 212A and the second magnetic pole portion 212B are engaged with each other while being displaced by 22.5° in the circumferential direction. In this state, the first stator yoke portion 210A has three grooves and cutouts for drawing out the exciting coil 24, and the second stator yoke portion 210B has three grooves and cutouts for drawing out the exciting coil 24. The cutout portions are configured such that their circumferential positions are aligned. As a result, both grooves and cutouts constitute a series of grooves and cutouts in the axial direction. In addition, a portion of the winding portion 24a of the excitation coil 24 and the terminal portion 24b are pulled out from a cutout of any one of the continuous three grooves.

As shown in FIG. 7, the excitation coil 24 includes a winding portion 24a, for example, a winding portion 24a in which a rectangular aluminum wire is wound in a circular manner in a plurality of stages in the radial direction and stacked in two stages in the axial direction. It is composed of a terminal portion 24b formed by bending the starting end portion and the terminal end portion of 24a into a Y shape. It should be noted that the wire is not limited to a rectangular wire, and may be formed by compressing a round wire, and the material is not limited to an aluminum wire, such as a copper-clad aluminum wire, a copper wire, a magnesium wire, or other materials. It may consist of

1 to 6, the U-phase stator 21U, the V-phase stator 21V, and the W-phase stator 21W are configured such that the first stator yoke portion 210A faces the top side, and the U-phase, The layers are laminated in the order of V phase and W phase. The V-phase stator 21V is laminated with its own magnetic pole portion shifted in phase from the magnetic pole portion of the U-phase stator 21U by 120° in electrical angle (15° in mechanical angle). The W-phase stator 21W is laminated with its own magnetic pole portions shifted in phase from the magnetic pole portions of the V-phase stator 21V by 120° in electrical angle (15° in mechanical angle).

Therefore, in the U-phase stator 21U, the V-phase stator 21V, and the W-phase stator 21W, the three grooves and cutouts for drawing out the exciting coil 24 are arranged such that the circumferential positions of the three grooves and the cutouts thereof are phase-shifted by an electrical angle of 120°. It is configured to match when stacked in a staggered manner. As a result, each of the three grooves of the U-phase stator 21U, the V-phase stator 21V, and the W-phase stator 21W are connected together in the axial direction.
With the configuration of the stator device 2 described above, the polyphase motor 1 according to the first embodiment is configured as a claw pole type motor.

On the other hand, the magnetic circuit extension member 23A has the same planar shape as the shape of the end face in the axial direction (laminating direction) of the U-phase stator 21U in the first embodiment. In addition, it is configured by laminating a plurality of thin electromagnetic steel sheets having non-directional magnetic properties. Then, it is attached to the end face of the U-phase stator 21U with, for example, an adhesive. As a result, the U-phase magnetic circuit is extended to the top side of the U-phase stator 21U, and the magnetic resistance of the U-phase magnetic circuit is reduced to the same level as the magnetic resistance of the V-phase magnetic circuit.

As shown in FIG. 8, the magnetic circuit expansion member 23A is recessed radially inward in conformity with the shape of the three grooves of the U-phase stator 21U on the outer peripheral portion, which are provided at positions facing each other in the axial direction. It has three recesses 23a. In addition, the diameter of each of the eight first magnetic pole portions 212A of the U-phase stator 21U on the inner peripheral portion is adjusted to match the shape of the axial end face of each of the first magnetic pole portions 212A, which are provided at positions axially facing the eight first magnetic pole portions 212A. It has eight projections 23b projecting inward in the direction. Due to such a shape, the magnetic circuit expansion member 23A is adhered in contact with the entire end faces of the first stator yoke portion 210A and the plurality of first magnetic pole portions 212A of the U-phase stator 21U. .

The magnetic circuit extension member 23B has the same configuration as the magnetic circuit extension member 23A, except that the three recesses 23a are axially opposed to the three grooves of the W-phase stator 21W. That is, the W-phase magnetic circuit is extended to the bottom side of the W-phase stator 21W to reduce the magnetic resistance of the W-phase magnetic circuit to the same level as the magnetic resistance of the V-phase magnetic circuit. In addition, due to such a shape, the magnetic circuit expansion member 23B is attached while being in contact with the entire end face portions of the second stator yoke portion 210B and the plurality of claw-shaped second magnetic pole portions 212B of the W-phase stator 21U. state.

The rotor device 3 has a cylindrical rotor yoke 31 and magnetic pole surfaces 2122A and 2122B of the first and second magnetic pole portions 212A and 212B on the inner peripheral portion of the U-phase stator 21U on the outer peripheral portion of the rotor yoke 31 with a predetermined gap therebetween. A ring-shaped U-phase magnet portion 32U having a configuration in which different magnetic poles are alternately and repeatedly arranged along the circumferential direction is provided at opposing positions. In addition, U is provided at a position facing the magnetic pole surfaces 2122A and 2122B of the first and second magnetic pole portions 212A and 212B of the inner peripheral portion of the V-phase stator 21V in the outer peripheral portion of the rotor yoke 31 with a predetermined gap. A V-phase magnet portion 32V having the same configuration as the phase magnet portion 32U is provided. Further, the U-phase magnetic pole faces 2122A and 2122B of the first and second magnetic pole portions 212A and 212B of the inner peripheral portion of the W-phase stator 21W on the outer peripheral portion of the rotor yoke 31 are opposed to each other with a predetermined gap. A W-phase magnet portion 32W having the same configuration as the magnet portion 32U is provided.

The U-phase magnet portion 32U, the V-phase magnet portion 32V, and the W-phase magnet portion 32W are provided so that the magnetic poles of the N and S poles are located at the same circumferential position (overlapping in the axial direction). Further, the U-phase magnet portion 32U, the V-phase magnet portion 32V, and the W-phase magnet portion 32W may be formed of segment magnets instead of ring-shaped magnets.

[About the action of the magnetic circuit expansion members 23A and 23B]
First, as shown in FIG. 9(a), the case where the magnetic circuit expansion members 23A and 23B are not provided in the stator device 2 will be described. In this case, the magnetic resistance of the V-phase magnetic circuit corresponding to the V-phase stator 21V sandwiched between the U-phase stator 21U and the W-phase stator 21W is the end phase magnetic resistance corresponding to the U-phase stator 21U and the W-phase stator 21W, respectively. It is lower than the magnetic resistance of the (U-phase, W-phase) magnetic circuits. That is, the magnetic flux Bv from the V-phase magnet portion 32V flowing in the V-phase magnetic circuit is more likely than the magnetic flux Bu from the U-phase magnet portion 32U flowing in the U-phase magnetic circuit when the U-phase stator 21U is laminated alone. is in a state where it is easy to flow. Similarly, the magnetic flux Bv flowing through the V-phase magnetic circuit is easier to flow than the magnetic flux Bw from the W-phase magnet portion 32W flowing through the W-phase magnetic circuit when the W-phase stator 21W is laminated alone. ing.

This is because the V-phase magnetic circuit shares both the second stator yoke portion 210B of the U-phase stator 21U and the first stator yoke portion 210A of the W-phase stator 21W. That is, the V-phase magnetic circuit is extended to both end sides in the stacking direction by the shared portion.

On the other hand, the U-phase magnetic circuit shares only the first stator yoke portion 210A of the V-phase stator 21V on the V-phase stator 21V side, and the W-phase magnetic circuit shares the V-phase stator 21V side on the V-phase stator 21V side. Only the second stator yoke portion 210B is shared. That is, each of the U-phase stator 21U and the W-phase stator 21W does not have a stator yoke portion that can be shared on the opposite side because there is no other stator on the side opposite to the V-phase stator 21V side.

As a result, the V-phase magnetic circuit has a larger cross-sectional area through which magnetic flux flows than the U-phase and W-phase magnetic circuits. In addition, the V-phase stator 21V has the same magnetic permeability as the U-phase stator 21U and the W-phase stator 21W, because the same material and manufacturing method are used. Therefore, the magnetic resistance of the V-phase magnetic circuit is lower than that of the U-phase and W-phase magnetic circuits, which are shared on only one side.

On the other hand, when the magnetic circuit expansion members 23A and 23B are provided, the U-phase magnetic circuit is expanded to the side opposite to the V-phase stator 21V side by the magnetic circuit expansion member 23A, and the W-phase magnetic circuit is expanded by the magnetic circuit expansion member 23A. The circuit is extended to the side opposite to the V-phase stator 21V side by the magnetic circuit extension member 23B. As a result, the cross-sectional area through which the magnetic flux flows is increased by the expanded amount, and the magnetic resistance is reduced as compared with the case where the magnetic circuit expansion members 23A and 23B are not provided.

That is, in the first embodiment, the magnetic circuit extension members 23A and 23B are arranged so that the magnetic resistance of the U-phase and W-phase magnetic circuits matches or substantially matches the magnetic resistance of the V-phase magnetic circuits. It is constructed with a shape and material that can reduce the reluctance of the magnetic circuit of the phase.

As a result, as shown in FIG. 9B, the magnetic resistance of the U-phase and W-phase magnetic circuits that are the end phases and the magnetic resistance of the V-phase magnetic circuit that is the intermediate phase are made uniform or substantially uniform. It is possible to reduce the torque ripple caused by the unbalanced magnetic resistance.

[Action and effect of the first embodiment]
The stator device 2 according to the first embodiment includes a U-phase stator 21U, a V-phase stator 21V, and a W-phase stator 21W made of a material having non-directional magnetic properties. U-phase stator 21U includes U-phase stator core 210U and U-phase excitation coil 24U; V-phase stator 21V includes V-phase stator core 210V and V-phase excitation coil 24V; A phase excitation coil 24W is provided. Further, U-phase stator core 210U, V-phase stator core 210V, and W-phase stator core 210W are arranged along the circumferential direction along first stator yoke portion 210A and inner peripheral portions of first stator yoke portion 210A, respectively. and eight claw-shaped first magnetic pole portions 212A each extending in the axial direction. In addition, a second stator yoke portion 210B and eight claw-like second rotors each extending in the axial direction are arranged side by side along the circumferential direction on the inner peripheral portion of the second stator yoke portion 210B. 2 magnetic pole portions 212B. The first stator yoke portion 210A and the second stator yoke portion 210B are arranged to face each other concentrically in the axial direction, and each first magnetic pole portion 212A extends toward the facing second stator yoke 210B side. Each second magnetic pole portion 212B extends toward the opposing first stator yoke 210A. Furthermore, the first stator yoke portion 210A and the second stator yoke portion 210B sandwich the excitation coil 24, and the first and second magnetic pole portions 212A and 212B are alternately arranged along the circumferential direction. They are arranged side by side with each other.

The U-phase stator 21U, the V-phase stator 21V, and the W-phase stator 21W are stacked in the order of U-phase, V-phase, and W-phase from the top side with their respective centers aligned, and both ends in the stacking direction are provided with magnetic circuit expansion members 23A and 23B for expanding the magnetic resistance of the magnetic circuits corresponding to the respective phases of the U-phase stator 21U and W-phase stator 21W at both ends.

With this configuration, the magnetic circuit extension members 23A and 23B can extend the magnetic circuits corresponding to the U-phase and W-phase. This makes it possible to reduce the magnetic resistance of the U-phase and W-phase magnetic circuits as compared with the case where the magnetic circuit expansion members 23A and 23B are not provided. As a result, it is possible to reduce the imbalance in magnetic resistance between the V-phase magnetic circuit and the U-phase and W-phase magnetic circuits.

Further, in the stator device 2 according to the first embodiment, the magnetic circuit expansion members 23A and 23B are configured so that the magnetic resistance of the magnetic circuits corresponding to the U-phase and W-phase is equal to that of the magnetic circuit corresponding to the V-phase. The magnetic circuits corresponding to the U-phase and W-phase are expanded so as to match or substantially match.
With this configuration, the magnetic resistances of the U-phase, V-phase, and W-phase magnetic circuits can be made uniform or substantially uniform, so that the unbalanced magnetic resistance can be reduced more reliably. Become.

Further, in the stator device 2 according to the first embodiment, the U-phase, V-phase, and W-phase stator cores 210U, 210V, and 210W further include at least a plurality of first and second magnetic pole portions 212A and 212B, which insulate their surfaces. It is composed of a molded body (powder core) obtained by compressing magnetic powder. Furthermore, the magnetic circuit extension members 23A and 23B are composed of a laminated body (laminated core) in which thin electromagnetic steel plates are laminated.

With this configuration, since at least the magnetic pole portions of the stator core are made of dust cores, it is possible to configure a magnetic circuit having a three-dimensional spread, and to improve magnetic performance. In addition, since the magnetic circuit extension members 23A and 23B are composed of laminated cores having magnetic properties superior to those of dust cores, the magnetic circuit extension members 23A and 23B are thinner than when composed of dust cores. It becomes possible to This makes it possible to configure the device more compactly.

Further, the polyphase motor 1 according to the first embodiment includes a stator device 2 and a plurality of first and second U-phase, V-phase and W-phase stators 21U, 21V and 21W concentrically with the stator device 2. The magnetic pole portions 212A and 212B are provided with the rotor device 3 arranged opposite to each other with a predetermined gap in the radial direction. The rotor device 3 has an annular rotor yoke 31 and a plurality of first magnetic pole portions 212A and 212B of a U-phase stator 21U provided on the outer peripheral portion of the rotor yoke 31. It has a U-phase magnet portion 32U in which different magnetic poles are alternately and repeatedly arranged along the direction. In addition, a V-phase magnet portion 32V having the same configuration as the U-phase magnet portion 32U is disposed facing the magnetic pole surfaces of the plurality of first magnetic pole portions 212A and 212B of the V-phase stator 21V with a predetermined gap in the radial direction. Prepare. Further, a W-phase magnet portion 32W having the same configuration as the U-phase magnet portion 32U is arranged facing the plurality of first magnetic pole portions 212A and 212B of the W-phase stator 21W with a predetermined gap in the radial direction.

With this configuration, the same actions and effects as those of the stator device 2 can be obtained, and these actions and effects make it possible to reduce torque ripple when the motor is driven, so that more stable operation is possible. It becomes possible to provide a motor.

[Second embodiment]
Next, a second embodiment of the invention will be described.
〔composition〕
In the second embodiment, in the stator device 2 of the polyphase motor 1 of the first embodiment, when the U-phase stator 21U, the V-phase stator 21V and the W-phase stator 21W are laminated, an inclusion is interposed between the stators. It differs from the first embodiment in that the
In the following, the same components as those of the first embodiment are denoted by the same reference numerals, and descriptions thereof are omitted as appropriate, and different points are described in detail.

As shown in FIG. 10, a stator device 2A according to the second embodiment is provided between the U-phase stator 21U and the V-phase stator 21V and between the V-phase stator 21V and the W-phase stator 21V in the stator device 2 of the first embodiment. Annular inclusions 25 are interposed between them and the stator 21W.
Here, the inclusions 25 are made of, for example, a non-magnetic material, and are not limited to materials, and may simply be a gap.

In the stator device 2 of the first embodiment, the stator device 2A has a magnetic circuit expansion member 26A made of dust cores of the same shape instead of the magnetic circuit expansion members 23A and 23B made of laminated cores. and 26B.

[Action and effect of the second embodiment]
In a stator device 2A according to the second embodiment, a U-phase stator 21U, a V-phase stator 21V, and a W-phase stator 21W are laminated with inclusions 25 made of non-magnetic material interposed between the stators.
With this configuration, it is possible to reduce the magnetic flux flowing through the shared portion compared to a configuration in which the stators are laminated while contacting each other, so it is possible to reduce the imbalance of the magnetic resistance between the phases. becomes.

Further, the stator device 2A according to the second embodiment is further provided with magnetic circuit expansion members 26A and 26B at both ends in the lamination direction.
With this configuration, it is possible to further reduce the imbalance of magnetic resistance between the phases.

Here, just by interposing the inclusion 25, it is not possible to completely prevent the V-phase stator 21V from sharing the magnetic circuit with the adjacent stator due to factors such as magnetic flux wraparound. The imbalance is not completely eliminated. Therefore, by providing the magnetic circuit extension members 26A and 26B, it is possible to compensate for the unsolved problem.

In addition, by interposing the inclusion 25, the difference in magnetic resistance between the phases can be reduced compared to the case where the inclusion 25 is not interposed. The extension members 23A and 23B remain the same and can be constructed from a dust core that has inferior magnetic properties to the laminated core. Depending on the magnitude of the magnetic resistance difference, the magnetic circuit extension members 26A and 26B can be made thinner.

[Modification]
In each of the above-described embodiments, an example in which the shape of the magnetic circuit expansion member is the same as the stator end face in a plan view has been described, but the configuration is not limited to this configuration, and any magnetic circuit expansion function may be provided, for example. Other shapes such as a circular belt shape in plan view may be used.
In addition, in the first embodiment, the magnetic circuit expansion member is composed of a laminated core, and in the second embodiment, it is composed of a dust core. may be configured.

Further, in each of the above-described embodiments, the three-phase stators are arranged with a phase shift of "120°", but the present invention is not limited to this configuration. For example, another configuration may be employed, such as arranging the three-phase stators without shifting the phases, and arranging the magnet portion side of the rotor device 3 with a phase shift of 120 degrees.
Further, in each of the above-described embodiments, an example in which the polyphase motor 1 is configured as a three-phase motor has been described, but the configuration is not limited to this configuration, and may be configured with four or more phases.

In each of the above-described embodiments, the stator core 210 has been described as an example in which the stator core 210 is configured by a molded body (powder core) formed by compressing magnetic powder whose surface is electrically insulated. It may be composed of a laminate (laminated core) in which magnetic steel sheets are laminated, or a non-laminated electromagnetic steel sheet. Alternatively, for example, the first magnetic pole portions 212A and 212B may be configured with dust cores, and other portions may be configured with laminated cores.

Further, in each of the above-described embodiments, the plate-shaped magnetic circuit expansion members are attached to the end surfaces of the stator at both ends, but the configuration is not limited to this. For example, other configurations may be used, such as providing them close to the end face (with a gap), or applying paste-like iron powder having an expanding function to the end face.

1 polyphase motors 2, 2A stator device 3 rotor device 4 side frames 4a, 4b flange 4c drawing portion 5A top frame 5B bottom frame 6 rotating shaft 7 reduction gear 8 stator fixing member 9A, 9B bearings 21U, 21V, 21W U phase , V-phase, W-phase stators 23A, 23B, 26A, 26B Magnetic circuit expansion member 23a Concave portion 23b Convex portion 24U, 24V, 24W U-phase, V-phase, W-phase excitation coil 24a Winding portion 24b End portion 31 Rotor yoke 32U, 32V , 32W U-phase, V-phase, W-phase magnet portions 210U, 210V, 210W U-phase, V-phase, W-phase stator cores 210A, 210B first and second stator core portions 211A, 211B first and second stator yokes 212A, 212B magnetic pole

Claims (6)

an annular stator core made of a material having non-directional magnetic properties and having a plurality of magnetic pole portions arranged circumferentially along the inner or outer peripheral portion and each extending in the axial direction; , and an annular exciting coil disposed close to the radial back side of the plurality of magnetic pole portions of the stator core (N is a natural number of 3 or more) or more,
The N or more stators are stacked with their respective centers aligned, and magnetic circuit expansion members are provided at both ends in the stacking direction for expanding the magnetic circuit corresponding to each phase of the stators at both ends. is provided ,
The magnetic circuit expansion member is such that the magnetic resistance of the magnetic circuit corresponding to each phase of the stators at both ends corresponds to the magnetic resistance of the magnetic circuit corresponding to each phase of the intermediate stator sandwiched between the stators at both ends. a stator device for a polyphase motor, configured to extend the magnetic circuits corresponding to the respective phases of the stators at the two end portions so as to coincide with or substantially coincide with . 2. The stator device for a multiphase motor according to claim 1 , wherein said magnetic circuit expansion member is composed of an electromagnetic steel sheet, a laminated body in which thin electromagnetic steel sheets are laminated, or a molded body in which magnetic powder is compressed. 3. The stator device for a multi-phase motor according to claim 1 , wherein at least the plurality of magnetic pole portions of the stator core are formed of compacts obtained by compressing magnetic powder. each stator core includes two annular stator yoke portions,
The two stator yoke portions are arranged to face each other in the axial direction, and a plurality of the magnetic pole portions are provided on the inner or outer peripheral portion of each of the stator yoke portions to extend toward the opposing counterpart,
4. The two stator yoke portions sandwich the exciting coil and are arranged in mesh with each other so that the magnetic pole portions are alternately arranged along the circumferential direction. A stator device for a polyphase motor according to claim 1. The stator device for a polyphase motor according to any one of claims 1 to 4 , wherein the N or more stators are laminated with inclusions made of a non-magnetic material interposed between the stators. A stator device for a polyphase motor according to any one of claims 1 to 5 ;
an annular rotor yoke arranged concentrically with the stator device for a polyphase motor and opposed to each of the plurality of magnetic pole portions of the N or more stators with a predetermined gap in the radial direction; and an inner circumference of the rotor yoke. The magnetic pole portions of each stator, which are provided on the side facing the plurality of magnetic pole portions among the outer peripheral portion and the outer peripheral portion, face the magnetic pole portions of each stator with a predetermined gap in the radial direction, and different magnetic poles are alternately repeated along the circumferential direction. a rotor having N magnet portions arranged thereon.

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