JP2011223751A - Rotor and stator core - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a more efficient rotor which reduces losses caused by magnetic resistance and eddy current, and a stator core used for the rotor.SOLUTION: A stator core 21 is configured by annularly arranging a plurality of unit cores C for which wires 40 comprised of magnetic material are bundled to be approximately U-shaped, and each of the unit cores C is arranged while turning an open end OP toward an annular center axis. Teeth 32 of the stator core 21 are formed from single-side parts Q1, Q2 in contact with each other of two adjacent unit cores (e.g., unit cores C1 and C2) in the unit cores C arranged annularly. A rotor includes the stator core 21 in a stator.

Description

  The present invention relates to a rotating machine such as a generator or an electric motor, and a stator core used in the rotating machine.

  As is well known, a rotating machine such as a generator or an electric motor includes a stator and a rotor, and converts rotational kinetic energy into electrical energy or converts electrical energy into rotational kinetic energy. Equipment. In a rotating machine in which a coil is provided on the stator side, a substantially annular stator core formed of a magnetic material such as soft iron and provided with a plurality of teeth (pole teeth) around which the coil is wound is provided along the rotation direction of the rotor. Used. Many conventional stator cores are configured by combining predetermined-shaped core segment pieces in order to facilitate manufacture.

  6 and 7 are diagrams illustrating an example of a core division piece constituting a conventional stator core. Each of the core division pieces 100 and 110 shown in FIGS. 6 and 7 has a substantially T-shaped cross section in a plane orthogonal to the rotation axis of the rotor. A core split piece 100 shown in FIG. 6 is formed by integrally forming an arc-shaped yoke portion 101 and a tooth 102 extending toward the center of curvature of the yoke portion 101. On the other hand, the core division piece 110 shown in FIG. 7 has a shape in which the teeth 112 extend toward the curvature center of the yoke portion 111 by joining the linear teeth 112 to the arc-shaped yoke portion 111. .

  In the core segment 100 shown in FIG. 6, the easy magnetization direction, which is the direction in which the magnetic resistance is small, is set in the direction along the length direction of the teeth 102. As described above, since the yoke part 101 and the teeth 102 are integrally formed in the core segment 100, the easy magnetization direction D101 in the yoke part 101 and the easy magnetization direction D102 in the teeth 102 are the same direction. . On the other hand, the core segment 100 shown in FIG. 7 is configured such that the easy magnetization direction D111 in the yoke portion 111 and the easy magnetization direction D112 in the teeth 112 intersect each other.

  Further, Patent Document 1 below discloses another example of a conventional stator core. FIGS. 8A and 8B are diagrams showing another example of the core divided pieces constituting the conventional stator core, wherein FIG. 8A is a perspective view of the core divided pieces, and FIG. 8B is a view showing a combination of the core divided pieces. is there. The core split piece 200 shown in FIG. 8A is composed of a yoke portion 201 and two tooth portions 202, and has a substantially U-shaped cross section in a plane orthogonal to the rotation axis of the rotor. The easy magnetization direction D200 of the core segment 200 is set in a direction from one tooth portion 202 to the other tooth portion 202 via the yoke portion 201.

  As shown in FIG. 8B, a plurality of core split pieces 200 shown in FIG. 8A are arranged along the rotation direction R100 of the rotor so that the teeth portions 202 are in contact with each other. One tooth 203 is formed by the teeth portions 202 of the adjacent core division pieces 200 arranged in this manner. In addition, the part enclosed with the broken line in FIG.8 (b) is a part corresponded to the core division | segmentation pieces 100 and 200 shown in FIG. 6, FIG.

JP 2007-82300 A

  Meanwhile, the core segment 100 shown in FIG. 6 intersects the magnetic path P100 and the easy magnetization direction D101 in the yoke portion 101, and the core segment 110 shown in FIG. 7 has a tooth at the junction between the yoke portion 111 and the tooth 112. Since the magnetic path of the magnetic flux that enters the yoke portion 111 from 112 intersects the easy magnetization direction D111 of the yoke portion 111, there is a problem that the magnetic resistance increases. Further, the core segment 110 shown in FIG. 7 has a problem in that the magnetic resistance increases due to the presence of a gap (gap that cuts the magnetic path) in the joint because the teeth 112 are joined to the yoke portion 111. .

  In the core segment 200 shown in FIG. 8, one tooth 203 is formed from a plurality of tooth portions 202, and the cross-sectional area of the tooth 203 through which eddy current flows can be reduced, so that the eddy current is reduced to some extent. It is thought that you can. However, in recent years, the demand for energy saving is increasing, and it is necessary to further reduce the loss due to eddy current. In order to realize further energy saving, it is considered necessary to increase the efficiency of the rotating machine by reducing the magnetic resistance as much as possible in addition to reducing the loss due to the eddy current.

  This invention is made | formed in view of the said situation, and it aims at providing the stator core used for the more efficient rotary machine which reduced the loss resulting from a magnetic resistance and an eddy current, and the said rotary machine. .

In order to solve the above problems, a rotating machine according to the present invention is a rotating machine (1) including a rotatable rotor (10) and a stator (20) arranged around the rotor. A stator core (21) having a plurality of teeth (32) around which a coil (22) is wound is arranged in a state of projecting toward the rotor along the rotation direction of the rotor, and the stator core is magnetic A plurality of unit cores (C, C1, C2, C3) in which wire rods (40) made of a material are bundled in a substantially U-shape are arranged along the rotation direction of the rotor with the open end (OP) facing the rotor side. It is characterized by being arranged.
Further, in the rotating machine according to the present invention, the teeth are formed by one side portion (Q1, Q2) of two adjacent unit cores that are adjacent to each other among the unit cores arranged along the rotation direction of the rotor. It is characterized by being.
The rotating machine of the present invention is characterized in that the teeth have a circular cross-sectional shape.
Moreover, in the rotating machine of the present invention, the wire is characterized in that the direction of easy magnetization (D1) is set in the longitudinal direction. In the rotating machine of the present invention, the wire has a rectangular cross-sectional shape. It is characterized by being.
The stator core of the present invention includes a substantially annular yoke (31) and a plurality of coils (22) wound around the yoke (31) so as to protrude toward the central axis of the yoke along the circumferential direction of the yoke. A stator core (21) having a plurality of unit cores (C, C1, C2, C3) in which a wire (40) made of a magnetic material is bundled in a substantially U shape. The open ends (OP) are arranged along the circumferential direction of the yoke toward the central axis of the yoke, and the teeth are formed of the unit cores arranged along the circumferential direction of the yoke. One of the two unit cores adjacent to each other is formed by one side portion (Q1, Q2) contacting each other.

  According to the present invention, there is provided a stator core configured by arranging a plurality of unit cores in which wire rods made of a magnetic material are bundled in a substantially U shape and arranged along the circumferential direction of the yoke with the opening end directed toward the central axis of the yoke. Since it uses, there exists an effect that the more efficient rotary machine which reduced the loss resulting from a magnetic resistance and an eddy current is realizable.

It is a front sectional view of a three-phase AC motor as a rotating machine according to an embodiment of the present invention. It is a front sectional view of a stator core according to an embodiment of the present invention. It is a perspective view which shows the unit core which comprises a stator core. It is a figure for demonstrating the effect by the cross-sectional shape of teeth. It is a figure for demonstrating the effect by using a wire. It is a figure which shows an example of the core division piece which comprises the conventional stator core. It is a figure which shows an example of the core division piece which comprises the conventional stator core. It is a figure which shows the other example of the core division | segmentation piece which comprises the conventional stator core.

  Hereinafter, a rotating machine according to an embodiment of the present invention will be described in detail with reference to the drawings. In the following embodiments, a case where the rotating machine is a three-phase AC motor (electric motor) that is rotationally driven by a three-phase AC supplied from the outside will be described as an example.

  FIG. 1 is a front sectional view of a three-phase AC motor as a rotating machine according to an embodiment of the present invention. As shown in FIG. 1, the three-phase AC motor 1 of the present embodiment includes a rotor 10 as a rotor configured to be rotatable, and a stator 20 as a stator disposed around the rotor 10. When the three-phase alternating current from the outside is supplied to the stator 20, the rotor 10 is rotationally driven.

  The rotor 10 includes a rotation shaft 11 and a rotor core 12, and is configured to be rotatable around the central axis of the rotation shaft 11. The rotating shaft 11 is a cylindrical member extending in a direction perpendicular to the paper surface, and is rotatable around a central axis by being supported by a bearing or the like (not shown). The rotor core 12 is provided as a field core around the rotating shaft 11 and includes a plurality of permanent magnets (not shown) therein. By this permanent magnet, an alternating magnetic field along the circumferential direction of the rotating shaft 11 is formed on the surface of the rotor core 12.

  The stator 20 includes a stator core 21, a coil 22, and a casing 23, and rotationally drives the rotor 10 by forming a rotating magnetic field around the rotor 10 by three-phase alternating current supplied from the outside. The stator core 21 is a member provided as an armature core around the rotor 10. FIG. 2 is a front sectional view of a stator core according to an embodiment of the present invention.

  As shown in FIG. 2, the stator core 21 has a substantially annular yoke 31 and a plurality of coils 22 around which a coil 22 is wound in a state of projecting toward the central axis of the yoke 31 along the circumferential direction of the yoke 31. Teeth 32. The teeth 32 provided on the stator core 21 function as magnetic poles when a three-phase alternating current is supplied to the wound coil 22. The stator core 21 is arranged around the rotor 10 so that the protruding direction of each tooth 32 is directed to the rotation axis of the rotor 10, and in this arrangement, a predetermined interval (for example, a distance from the rotor core 12) is set. The protrusion amount of the teeth 32 is set to be about several millimeters.

  Here, as shown in FIG. 2, the stator core 21 is configured by arranging a plurality of unit cores C. FIG. 3 is a perspective view showing a unit core constituting the stator core. As shown in FIG. 3, the unit core C is formed by bundling a plurality of wire rods 40 formed of a magnetic material such as soft iron into a substantially U shape. The plurality of wire rods 40 constituting the unit core C are linear members whose cross-sectional shape is a rectangular shape of about 0.5 to 1 mm square, and the easy magnetization direction D1 is set in the longitudinal direction. is there.

  An insulation coating (coating) is formed around each of the wires 40 as necessary. Thus, the reason why the unit core C forming the stator core 21 is formed by bundling the plurality of wires 40 is to reduce the loss of the three-phase AC motor 1 by reducing the eddy current generated in the stator core 21. The reason why the easy magnetization direction D1 is set in the longitudinal direction of the wire 40 is to reduce the magnetic resistance. In the following, when each unit core C shown in FIG. 3 needs to be distinguished, the explanation will be made with reference to different symbols (C1, C2, C3).

  As shown in FIG. 2, the stator core 21 is configured by arranging a plurality of unit cores C having the above configuration along the circumferential direction of the yoke 31 with the opening end OP directed toward the central axis of the yoke 31. The Here, the teeth 32 are formed by one side portion of two adjacent unit cores of the plurality of unit cores C arranged in contact with each other. Specifically, in the example shown in FIG. 3, one tooth 32 is formed by one side Q2 of the unit core C1 and one side Q1 of the unit core C2, and one side Q2 of the unit core C2 and the unit core C3. Another one tooth 32 is formed by one side portion Q1.

  Further, as shown in FIG. 3, the teeth 32 are formed in a substantially circular cross-sectional shape. That is, both side portions (one side portion Q1, Q2) of the unit core C have a substantially semicircular cross-sectional shape, and one side portions of the two adjacent unit cores C come into contact with each other. Teeth 32 having a substantially circular shape is formed. As described above, the cross-sectional shape of the teeth 32 is substantially circular. The gap between the teeth 32 and the coil 22 wound around the teeth 32 is reduced, thereby reducing the winding material and reducing the winding resistance. This is to increase the efficiency of the three-phase AC motor 1 by reducing it as much as possible. In addition, it is possible to increase the number of turns of the winding in the same shape, and it is expected that the output is increased and the electric motor is downsized.

  The coil 22 is wound around the teeth 32 included in the stator core 21, and three-phase alternating current supplied from the outside flows, so that the teeth 32 of the stator core 21 are used as magnetic poles. Specifically, the coil 22 has a plurality of coils that are Y-connected or Δ-connected and are supplied with current of each phase of the three-phase AC (U-phase, V-phase, W-phase). A coil to which current is supplied, a coil to which V-phase current is supplied, and a coil to which U-phase current is supplied are sequentially wound around teeth 32 arranged on the stator core 21 along the circumferential direction of the yoke 31. ing. When a three-phase alternating current is supplied to the coil 22, the teeth 32 are sequentially magnetized to form a rotating magnetic field.

  The casing 23 is an annular member that covers the outer periphery of the stator core 21, and houses the rotor 10 (part of the rotating shaft 11 and the rotor core 12), the stator core 21, and the coil 22. Further, the casing 23 also functions as a “tag” that joins the plurality of divided cores C together. In addition, as a method for joining the split cores C, it is possible to use a method of joining by bonding or the like, in addition to using the casing 23 as “tagar”.

  Next, the operation of the three-phase AC motor 1 having the above configuration will be briefly described. When three-phase AC from the outside is supplied to the three-phase AC motor 1, the current of each layer of the three-phase AC flows through the coil 22 provided in the stator 20. Then, the teeth 24 around which the coil 22 is wound are sequentially magnetized, and a rotating magnetic field is formed along the rotation direction of the rotor 10. Then, the rotor core 12 having an alternating magnetic field formed on the surface interacts with the rotating magnetic field, and the rotor 14 is rotationally driven by generating an attractive force and a repulsive force.

  FIG. 4 is a diagram for explaining the effect of the cross-sectional shape of the teeth. First, as shown in FIG. 4B, consider a tooth 300 in which a plurality of strip members 301 having a rectangular cross-sectional shape are stacked, and the cross-sectional shape is a rectangular shape. Since the coil 302 wound around the teeth 300 is bent at the four corners of the teeth 300, the coil 302 has a substantially square ring shape. Here, since the coil cannot be bent at right angles at the four corners of the tooth 300 due to the rigidity of the coil, a large gap V2 is generated between the teeth 300 and the coil 302 at the four sides of the tooth 300, and the winding is performed. The material length becomes longer and the winding resistance becomes larger.

  Next, as shown in FIG. 4A, consider a tooth 32 having a substantially circular cross-sectional shape formed using a unit core C formed of a wire 40. The coil 22 wound around the teeth 32 has a substantially annular shape along the cross-sectional shape of the teeth 32, and can be wound with the coil 22 being more closely attached to the teeth 32. Then, the gap V1 between the tooth 32 and the coil 22 is reduced, the material length of the winding is shortened, and the winding resistance is reduced. As a result, the efficiency of the three-phase AC motor 1 can be increased.

  FIG. 5 is a diagram for explaining the effect of using a wire. First, when a plurality of strip members 301 having a rectangular cross section are used, the eddy current flow path P2 extends in the longitudinal direction of the strip member 301 as shown in FIG. Can not be reduced. Next, when the wire 40 having a rectangular cross section is used, the eddy current flow path P1 can be made extremely small as shown in FIG. be able to.

  As described above, in the present embodiment, a plurality of unit cores C in which the wire 40 made of a magnetic material whose longitudinal direction is set to the easy magnetization direction are bundled in a substantially U shape, and the opening end OP faces the rotor 10 side. Since the stator cores 21 arranged in the direction of rotation of the rotor 10 are used, the magnetic resistance and eddy current can be greatly reduced. In the present embodiment, the cross-sectional shape of the teeth 32 provided on the stator core 21 is substantially circular, and the coil 22 can be wound more tightly on the teeth 32. By shortening, winding resistance can be reduced. For this reason, in this embodiment, the efficiency of the three-phase AC motor 1 can be further increased.

  As mentioned above, although the rotary machine by one Embodiment of this invention was demonstrated, this invention is not restrict | limited to the said embodiment, It can change freely within the scope of the present invention. For example, in the above embodiment, a three-phase AC motor, which is a kind of electric motor, has been described as an example, but the present invention can also be applied to a generator. The present invention can also be applied to a rotating machine that uses a multiphase current other than three-phase alternating current.

  In the above embodiment, the case where the cross-sectional shape of the tooth 32 is substantially circular has been described as an example. However, the cross-sectional shape of the tooth 32 is substantially elliptical, rectangular, or other three-phase AC motor 1. An appropriate shape can be obtained according to the shape and characteristics. However, it is desirable for the coil to be wound around the shape to have a tight adhesion. Moreover, the wire 40 does not necessarily have a rectangular cross-sectional shape, and may have another shape such as a circular shape.

DESCRIPTION OF SYMBOLS 1 Three-phase alternating current motor 10 Rotor 20 Stator 21 Stator core 22 Coil 31 Yoke 32 Teeth 40 Wire C Unit core C1, C2, C3 Unit core D1 Easy magnetization direction OP Open end Q1, Q2 One side part

Claims (6)

In a rotating machine comprising a rotatable rotor and a stator disposed around the rotor,
The stator includes a stator core having a plurality of teeth around which coils are arranged in a state of projecting toward the rotor along the rotation direction of the rotor,
The stator core is formed by arranging a plurality of unit cores in which wire rods made of a magnetic material are bundled in a substantially U shape and arranged in the rotation direction of the rotor with an opening end facing the rotor. Rotating machine.   2. The rotation according to claim 1, wherein the teeth are formed by one side portion of two unit cores adjacent to each other among the unit cores arranged along the rotation direction of the rotor. Machine.   The rotating machine according to claim 2, wherein the teeth have a circular cross-sectional shape.   The rotating machine according to any one of claims 1 to 3, wherein the wire has an easy magnetization direction set in a longitudinal direction.   The rotating machine according to any one of claims 1 to 4, wherein the wire has a rectangular cross-sectional shape. A stator core having a substantially annular yoke and a plurality of teeth that are arranged in a state of projecting toward the central axis of the yoke along the circumferential direction of the yoke and on which a coil is wound,
The stator core is configured by arranging a plurality of unit cores in which wire rods made of a magnetic material are bundled in a substantially U shape and arranged along the circumferential direction of the yoke with the opening end directed toward the central axis of the yoke,
The teeth are formed by one side portion of two unit cores adjacent to each other among the unit cores arranged along the circumferential direction of the yoke.

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