JP4847248B2 - Axial gap motor - Google Patents

Description

  The present invention relates to an axial gap type electric motor, and more particularly to an axial gap type electric motor provided with an eccentricity allowing structure for a rotating shaft.

2. Description of the Related Art Conventionally, as an electric motor corresponding to an electric motor that requires low speed and high torque, there is an axial gap type electric motor in which a stator and a rotor are arranged to face each other in the direction of a rotation axis. A conventional axial gap type electric motor includes a stator around which a coil is wound, a rotor that is arranged to face the coil in the direction of the rotation axis, and a plurality of pairs of permanent magnets are arranged in a circumferential magnetomotive force type. And a rotating magnetic field is generated by passing a current through the stator coil, and the rotor is rotated by a magnetic attraction force and a repulsive force between the stator and the rotor (Patent Literature). 1 and 2).
JP 2002-153028 A Japanese Patent Laid-Open No. 11-187635

  However, in these conventional axial gap type electric motors, the center line of the stator and the rotation axis center line of the rotor are configured as the same center line. For example, the rotation center line of the rotated member connected to the rotor is also the rotor. It is necessary to make it the same as the rotation center line, but considering the assembly accuracy, etc., the variation cannot be removed, and in order to allow deviation (eccentricity) of this center line, for example, the Oldham coupling is rotated. Installation between the child and the rotated member is performed.

  For this reason, the subject of a cost increase and a weight increase arises with the setting of Oldham coupling.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide an axial gap type electric motor having an eccentricity allowing structure.

The present invention relates to a rotor in which a plurality of permanent magnets or coils are installed at predetermined intervals in the circumferential direction, and the permanent magnets or coils so as to face one of the permanent magnets or coils in the rotation axis direction of the rotor. An axial gap type electric motor having an electric motor portion disposed so as to face the rotor with a predetermined gap in the rotation axis direction of the rotor. A case in which the rotor and the stator are housed and the stator is fixed to the inner surface of the rotor, and the rotor is slidably supported on the surface of the case orthogonal to the center line of the case and, and an axial air gap type electric motor characterized by comprising a bearing for rotatably supporting the rotor on the rotary axis of the rotor.

In the present invention, since the bearing that allows the deviation between the rotation center line of the rotor and the center line of the case, that is, the center line of the stator, is provided, it is provided between the rotor and the rotated member to allow the deviation. Oldham coupling can be abolished, and cost reduction and weight reduction can be achieved.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a cross-sectional view including a rotation center line of a rotor 3 showing a configuration of an axial gap type electric motor 1 of the present invention.

  In this embodiment, the rotor shaft 2 connected to the member to be rotated, the rotor 3 fixed to the rotor shaft 2, and a pair of fixed members provided to face the rotor 3 with a predetermined gap in the rotor shaft direction. A plurality of electric motor parts 1 a including the child 4 are arranged in the rotor axial direction and housed in the case 5, thereby constituting the axial gap type electric motor 1. In the present embodiment, the description will be given using the axial gap type electric motor 1 provided with the two rows of electric motor portions 1a. However, the present invention is not limited to this, and the axial gap formed by a plurality of or one row of electric motor portions 1a may be used. The type motor 1 may be used.

FIG. 2 is a diagram for explaining the shape of the rotor 3. The rotor 3 includes four arm portions 6 extending in a direction orthogonal to the center line of the rotor shaft 2 connected to a rotation member (not shown), and these arm portions 6 are equally spaced in the circumferential direction (90 in FIG. 2). Are arranged at intervals of °. A cylindrical second member 7 that is coaxial with the roller shaft 2 that connects each arm 6 is fixed to the tip of each arm 6. The bearing 13 is installed in the 2nd member 7 in the position which faces the surface 5e orthogonal to the centerline of the case 5 mentioned later, and the rotation centerline direction of the rotor 3. FIG. The bearing 13 is rotating rotor 3 is slidably in a direction perpendicular to the center line of the rotor shaft 2 with respect to the surface 5e of the casing 5, and the center of the rotor shaft 2 rotor 3 with respect to the case 5 Supports rotation (spinning) around the line.

  As shown in FIG. 1, a permanent magnet 12 is attached to an intermediate portion of each arm portion 6 of the rotor 3 so as to sandwich the arm portion 6. For example, as shown in FIG. 3, the permanent magnet 12 is formed in a substantially fan shape when viewed from the axial direction, and is fixed to each arm portion 6. Further, the end surface 12 a of the permanent magnet 12 is formed as a surface orthogonal to the center line of the rotor 3. Needless to say, the number, shape, and the like of the permanent magnets 12 are not limited to those of the present embodiment.

  The pair of stators 4 are respectively provided at positions facing the permanent magnets 12 of the rotor 3 in the axial direction of the rotor shaft 2. The stator 4 includes a yoke portion 8, a teeth portion 9 that protrudes from the yoke portion 8 toward the rotor and has a substantially fan shape, and a coil 10 that is wound around the teeth portion 9. The yoke part 8 plays a role of fixing the tooth part 9 to the case 5 and rotating the magnetic flux of the tooth part 9 in the circumferential direction to flow to another tooth part 9. Further, the coil 10 is insulated from the tooth portion 9 via an insulator or the like (not shown).

A case 5 that houses each motor part 1a includes a main body part 5a having a bottomed cylindrical shape, a lid part 5b that closes an opening end of the main body part 5a and includes a through hole 5d through which the rotor shaft 2 passes, and a main body It is installed in parallel with the part 5a and the cover part 5b, and is comprised from the hollow disc-shaped partition plate 5c which divides the inside of the case 5 into two spaces 5x and 5y in the axial direction. The bottom surface of the main body portion 5 a, the lid portion 5 b, and the partition plate 5 c are configured by a surface 5 e formed in a direction orthogonal to the center line of the case 5.

  And the stator 4 is fixed to the surface 5e in each space 5x, 5y, the permanent magnet 12 of the rotor 3 is arrange | positioned facing each stator 4, and the motor part 1a is comprised. In addition, in the state where each electric motor unit 1a is configured, the respective gaps 14 in the axial direction between the rotor 3 and the pair of stators 4 opposed to the rotor 3 are set so as to have a predetermined value.

  Here, the through hole 5d of the case 5 is formed to be larger than the diameter of the rotor shaft 2 by a predetermined amount, and the rotor 3 is configured to be slidable in the orthogonal direction of the rotor shaft 2 as described above. The difference between the diameter of the through hole 5d and the diameter of the rotor shaft 2 defines the relative sliding amount of the rotor 3 in the orthogonal direction of the rotor shaft 2 with respect to the case 5.

Cylindrical members 7 connecting the front end portion of the arm portion 6 of the rotor 3, the axial end face 7a is formed so as to face the surface 5e of the casing 5 in the axial direction, the end face 7a of the member 7 The bearing 13 is disposed between the surface 5 e of the case 5. The bearing 13 can slide in a direction orthogonal to the rotation center line of the rotor shaft 2 of the rotor 3 with respect to the surface 5 e of the case 5, and the rotor shaft 2 of the rotor 3 on the surface 5 e of the case 5. Allows rotation around. The bearing 13 may be a slide bearing or the like, but is not limited to this, and any means that allows the rotor 3 to slide relative to the case 5 and rotate the rotor 3 may be used.

  In this embodiment, the rotor 3 is provided with a permanent magnet and the stator 4 is provided with a coil, but conversely, the rotor 3 may be provided with a coil and the stator may be provided with a permanent magnet.

  Next, the operation will be described.

  In the axial gap type electric motor of the present invention, for example, the coil 5 of the stator 4 is energized with the case 5 fixed and the rotor shaft 2 fixed to the rotor 3 connected to the rotated member. When the coil 10 of the stator 4 is energized, a rotating magnetic field is generated, and accordingly, the rotor 3 is rotated in a predetermined direction by the magnetic attractive force and repulsive force between the stator 4 and the rotor 3. Let By this rotation, a rotated member (not shown) connected to the rotor 3 rotates.

  Since the rotor shaft 2 is connected to the rotated member, the external force acting on the rotated member also acts on the rotor shaft 2. Since the rotor 3 includes a bearing 13 that can slide in a direction perpendicular to the center line of the rotor shaft 2 with respect to the stator 4, the rotor shaft 2 slides with the displacement of the rotated member. In such a case, sliding of the rotor 3 in a direction perpendicular to the center line of the stator 4 is allowed by the action of the bearing 13, and the rotor 3 is centered on a position eccentric to the center line of the stator 4. Can rotate.

  Further, when connecting the rotor shaft 2 and the rotated member, an allowable range of accuracy for matching the center line can be set large. For this reason, it is not necessary to provide a means for allowing eccentricity between the rotor shaft 2 and the rotated member, for example, an Oldham coupling, and cost reduction and weight reduction can be achieved.

  The present invention is not limited to the above-described embodiment, and it is obvious that various modifications can be made within the scope of the technical idea.

It is sectional drawing explaining the structure of the axial direction air gap type | mold electric motor 1 of this invention. It is a block diagram of a rotor. It is sectional drawing of the cross section AA of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Axial direction gap | interval motor 1a Motor part 2 Rotor shaft 3 Rotor 4 Stator 5 Case 5c Partition plate 6 Arm part 7 Member 8 Yoke 9 Teeth part 10 Coil 12 Permanent magnet 13 Bearing

Claims (4)

A rotor in which one of permanent magnets or coils is installed at a predetermined interval in the circumferential direction;
A stator provided with the other of the permanent magnet or the coil so as to face one of the permanent magnet or the coil in the rotation axis direction of the rotor,
In the axial gap type electric motor having the electric motor portion arranged so that the stator has a predetermined gap in the rotation axis direction of the rotor and faces the rotor,
A case in which the rotor and the stator are internally provided, and the stator is fixed to an inner surface thereof;
A bearing that slidably supports the rotor with respect to the surface of the case orthogonal to the center line of the case, and that rotatably supports the rotor around a rotation axis of the rotor . An axial gap type electric motor characterized by that. The said case is provided with the through-hole which the rotating shaft of the said rotor penetrates, The sliding amount of the said orthogonal direction of the said rotor is prescribed | regulated by the diameter difference of this through-hole and the said rotating shaft. The axial gap type electric motor according to 1. The rotor is provided with a cylindrical member on one outer peripheral side of the permanent magnet or coil,
2. The axial gap type electric motor according to claim 1, wherein the bearing is installed between the member and the case in a rotation axis direction of the rotor. Arranged perpendicular to the center line of the case, and provided with a partition plate for partitioning the inside of the case,
The axial gap type electric motor according to claim 1, wherein a predetermined number of the electric motor parts are arranged in the partitioned space .