JP2012050271A - Axial gap type motor - Google Patents

Abstract

In an axial gap type motor having a split core in which electromagnetic steel plates are laminated, peeling of the electromagnetic steel plates in the stacking direction is prevented.
An axial gap type motor (20) includes a housing (26), a stator (44), a receiving member (45), and a rotor (27). The stator core 46 of the stator 44 is formed in an annular shape by arranging a plurality of divided cores 48 formed by laminating electromagnetic steel plates 49 in the axial direction S1 in the circumferential direction C1. The receiving member 45 includes a first receiving portion 55 that receives one end surface 48 a of each divided core 48, a second receiving portion 56 that receives the other end surface 48 b of each divided core 48, and a fixing portion that fixes the receiving portions 55 and 56. 57. The rotor 27 includes a pair of annular permanent magnets 34 and 35 facing each other with the stator 44 sandwiched in the axial direction S1, and a rotor core 33 that couples the pair of permanent magnets 34 and 35 so as to be integrally rotatable. .
[Selection] Figure 2

Description

  The present invention relates to an axial gap type motor.

The axial gap type motor has a configuration in which a field element and an armature are arranged in the axial direction of the motor (see, for example, Patent Documents 1 to 3).
In Patent Documents 1 and 2, the armature core is formed using a dust core. In Patent Documents 2 and 3, a coil is attached to a recess or a tooth formed on the end face of the core.

JP 2006-14436 A Japanese Patent Publication No. 60-51352 JP-T 58-500584

  By the way, a stator may be used as an armature of an axial gap type motor. This stator has, for example, a stator core formed by arranging divided cores in which electromagnetic steel plates are laminated in the axial direction of the motor and arranged in the circumferential direction of the motor, and a coil wound around the teeth of each divided core. Thus, by forming the stator core from a magnetic steel sheet, it is possible to easily manufacture a motor having high strength and excellent magnetic characteristics as compared with the case where the stator core is formed of a dust core.

  However, such an axial gap type motor has a large component along the axial direction of the motor among the magnetic force acting between the stator and the rotor as the field magnet. For this reason, a large force is generated in the stator core to separate the laminated electromagnetic steel sheets. The electromagnetic steel sheets are fixed to each other by caulking or the like, but a part of the electromagnetic steel sheets may be peeled off by the magnetic force. From the viewpoint of more reliably suppressing the motor lock, it is preferable that such peeling does not occur.

  The present invention has been made under such a background, and an object of the present invention is to prevent peeling in the stacking direction of electromagnetic steel sheets in an axial gap type motor having a split core in which electromagnetic steel sheets are stacked.

  In order to achieve the above object, the present invention provides an annular stator core comprising a plurality of divided cores (48) formed by laminating electromagnetic steel plates (49) in the axial direction (S1) in the circumferential direction (C1). (46) and a stator (44) including a plurality of coils (47) wound around each split core, and a first receiving portion (55) for receiving one end face (48a) of each split core in the axial direction A non-magnetic receiving member (45; 45A) including a second receiving portion (56) for receiving the other end face (48b) of each of the divided cores, and a fixing portion (57) for fixing each of the receiving portions, and A rotor (27) including a pair of annular permanent magnets (34, 35) opposed to each other with the stator sandwiched in the axial direction, and a rotor core (33) coupling the pair of permanent magnets so as to be integrally rotatable. Axial characterized by having Providing cap-type motor (20) (claim 1).

  According to the present invention, the one end surface and the other end surface of each divided core are sandwiched between the receiving members. Thereby, it can suppress reliably by the receiving member that the electromagnetic steel plates which a split core adjoins are peeled off. Therefore, even if the magnetic force acting between the rotor and the stator acts as a periodic force for separating the electromagnetic steel sheets, it is possible to suppress (prevent) the peeling between the electromagnetic steel sheets.

The present invention may further include an annular housing (26) for accommodating the stator, and the outer peripheral surface (46a) of the stator core may be fixed to the inner peripheral surface (30a) of the housing. 2).
For example, in the case of a radial gap type motor in which the stator and the rotor are opposed to each other in the radial direction of the motor and the rotor is rotated using a magnetic flux directed in the radial direction, the magnetic force is an excitation force that vibrates the housing in the radial direction. Acts as As a result, when the housing is deformed in the radial direction, air outside the housing is vibrated, and noise is generated.

  On the other hand, according to the present invention, when the axial gap type motor is driven, an excitation force as a force acting periodically is generated in the stator along the axial direction. This exciting force is a force substantially parallel to the coupling surface (inner peripheral surface of the housing) between the stator and the housing. Therefore, it can suppress that a housing deform | transforms with said excitation force. For this reason, it can suppress that a housing receives the force from a stator and vibrates. Therefore, vibration of the air around the housing can be suppressed, and noise during driving of the motor can be further suppressed. Furthermore, by fixing the outer peripheral surface of the stator core to the inner peripheral surface of the housing, it is possible to more reliably suppress peeling between the electromagnetic steel plates of the stator core.

Moreover, in this invention, the sound absorption member (61, 62) arrange | positioned at the at least one edge part (31, 32) of the said housing may be further provided (Claim 3).
In this case, by arranging the sound absorbing member at the end of the housing, it is possible to suppress the vibration of the air inside the housing from being transmitted to the outside of the housing. Thereby, the noise at the time of the drive of an axial gap type motor can be suppressed more reliably.

In the present invention, each of the permanent magnets has a plurality of magnetic poles (34a, 35a) in the circumferential direction, and one of the permanent magnets is in the circumferential direction with respect to the other permanent magnet. There is a case where they are displaced by a predetermined angle (θ1).
In this case, the cogging torque during the rotation of the rotor can be suppressed. Thereby, since the vibration of the air around a rotor can be suppressed, the noise at the time of a motor drive can further be suppressed.

In the present invention, the rotor core may include an insertion portion (36d) for inserting the stator, and may further include a permanent magnet (63) fixed to the insertion portion (Claim 5).
In this case, torque can be applied to the permanent magnet fixed to the insertion portion using leakage magnetic flux from the stator, that is, magnetic flux that does not contribute to the rotation of the permanent magnet facing the stator in the axial direction. Thereby, the output (torque constant) of an axial gap type motor can be made higher.

  In addition, in the above, the numbers in parentheses represent reference numerals of corresponding components in the embodiments described later, but the scope of the claims is not limited by these reference numerals.

It is a mimetic diagram showing a schematic structure of an electric power steering device provided with an axial gap type motor concerning one embodiment of the present invention. It is sectional drawing which shows schematic structure of a motor, and has shown the cross section cut | disconnected by the cut surface parallel to the central axis of a motor. It is a disassembled perspective view which shows the principal part of a motor typically. It is a disassembled perspective view of a stator unit. It is sectional drawing of the principal part of another embodiment of this invention. It is a disassembled perspective view of the principal part of another embodiment of this invention.

Preferred embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic diagram illustrating a schematic configuration of an electric power steering apparatus including an axial gap motor according to an embodiment of the present invention. Referring to FIG. 1, an electric power steering device 1 includes a steering shaft 3 connected to a steering member 2 such as a steering wheel, an intermediate shaft 5 connected to the steering shaft 3 via a universal joint 4, A pinion shaft 7 connected to the intermediate shaft 5 via a universal joint 6, and a rack shaft 10 having a rack 9 that meshes with a pinion 8 provided at the tip of the pinion shaft 7 and extending in the left-right direction of the vehicle. Have.

  A tie rod 11 is connected to each end of the rack shaft 10. Each tie rod 11 is connected to a corresponding wheel 12 via a corresponding knuckle arm (not shown). When the steering member 2 is operated and the steering shaft 3 is rotated, this rotation is transmitted to the pinion 8 via the intermediate shaft 5 and the like, and the straight line of the rack shaft 10 along the left-right direction of the vehicle is driven by the pinion 8 and the rack 9. Converted into movement. Thereby, the steering of the wheel 12 is achieved.

The steering shaft 3 has a first steering shaft 13 as an input shaft connected to the steering member 2 and a second steering shaft 14 as an output shaft connected to the universal joint 4. The first and second steering shafts 13 and 14 are coaxially connected to each other via a torsion bar 15.
In the vicinity of the torsion bar 15, a torque sensor 16 that detects a relative rotational displacement amount between the first steering shaft 13 and the second steering shaft 14 due to torsion of the torsion bar 15 is provided. The detection signal of the torque sensor 16 is given to the control unit 17. The control unit 17 calculates the steering torque applied to the steering member 2 based on the detection signal from the torque sensor 16. The control unit 17 controls the driving of an axial gap type motor (hereinafter also simply referred to as a motor) 20 for assisting steering via a driver 19 based on the calculated steering torque, a vehicle speed detection signal from the vehicle speed sensor 18 and the like. To do.

The output rotation of the motor 20 is transmitted to the second steering shaft 14 after being decelerated by a reduction gear 21 as a gear device. The power transmitted to the second steering shaft 14 is further transmitted to the steering mechanism 22 including the rack shaft 10, the tie rod 11, the knuckle arm and the like via the intermediate shaft 5 and the like to assist the driver's steering.
For example, the motor 20 and the speed reducer 21 are arranged in a vehicle compartment of the vehicle while being held by a steering column (not shown). The reduction gear 21 includes a drive gear 23 and a driven gear 24 that are driven by the motor 20, and a gear housing 25 that accommodates these gears 23 and 24.

The drive gear 23 is a worm shaft as a small gear connected to the rotor 27 as an output shaft of the motor 20, and the driven gear 24 is engaged with the drive gear 23 and is a worm wheel as a large gear connected to the second steering shaft 14. It is. The drive gear 23 and the driven gear 24 form a worm reduction mechanism.
FIG. 2 is a cross-sectional view showing a schematic configuration of the motor 20, and shows a cross section cut along a cutting plane parallel to the central axis L <b> 1 of the motor 20. Referring to FIG. 2, the motor 20 is, for example, a three-phase brushless motor. This motor 20 is, for example, an 8-pole 9-slot brushless motor in which the number of magnetic poles of permanent magnets 34 and 35, which will be described later, is 8, and the number of slots is 9.

The motor 20 includes an annular housing 26, a rotor 27 housed in the housing 26, and an annular stator unit 28.
Hereinafter, the axial direction, the circumferential direction, and the radial direction of the stator unit 28 are referred to as an axial direction S1, a circumferential direction C1, and a radial direction R1, respectively. The axial direction S1, the circumferential direction C1, and the radial direction R1 coincide with the axial direction, the circumferential direction, and the radial direction of the rotor 27, respectively.

The housing 26 includes a cylindrical housing body 30, an end wall 31 that closes one end of the housing body 30, and a lid 32 that closes the other end of the housing body 30.
The end wall 31 is integrally formed with the housing main body 30 using a single material, and forms one end of the housing 26. A bearing holding hole 31 a is formed at the center of the end wall 31. The lid 32 is fitted to the other end of the housing main body 30 and is fixed to the housing main body 30 using a fixing screw or the like (not shown). The lid 32 forms the other end of the housing 26. A bearing holding hole 32 a is formed at the center of the lid 32.

The rotor 27 includes a rotor core 33 and a pair of permanent magnets 34 and 35 coupled to the rotor core 33 so as to be integrally rotatable.
The rotor core 33 is formed using a magnetic material, and includes a rotor shaft 36 and a pair of flanges 37 and 38 that protrude outward from the rotor shaft 36 in the radial direction R1. The rotor shaft 36 passes through the space in the housing 26. One end 36a of the rotor shaft 36 is rotatably supported in a bearing holding hole 31a of the end wall 31 of the housing 26 via a bearing 39 such as an angular ball bearing. Of the intermediate portion of the rotor shaft 36, a portion in the vicinity of the other end portion 36 b is rotatably supported by the bearing holding hole 32 a of the lid 32 via a bearing 40 such as an angular ball bearing. The bearings 39 and 40 are adapted to receive a thrust force acting on the rotor shaft 36. The other end 36 b of the rotor shaft 36 protrudes from the housing 26. The other end 36b is connected to the drive gear 23 (see FIG. 1) through a joint (not shown).

Referring to FIG. 2, the flange 37 is formed integrally with the rotor shaft 36. Note that the rotor shaft 36 and the flange 37 may be formed as separate members, and the flange 37 may be fixed to the rotor shaft 36. The flange 37 is formed in an annular shape surrounding the rotor shaft 36 and is disposed adjacent to the end wall 31.
The flange 38 is formed using a member different from the rotor shaft 36. The flange 38 is formed in an annular shape surrounding the rotor shaft 36 and is disposed adjacent to the lid 32. The outer diameter of the flange 38 and the outer diameter of the flange 37 are substantially the same.

  The flange 38 is fixed to an intermediate portion of the rotor shaft 36. Specifically, a part of the rotor shaft 36 on the other end 36 b side is formed with a smaller diameter than other portions of the rotor shaft 36. A flange 38 is fitted to the small diameter portion. The flange 38 is connected to the rotor shaft 36 so as to be integrally rotatable by, for example, spline coupling. The flange 38 is restricted from moving in the axial direction with respect to the rotor shaft 36 by an annular step 36 c of the rotor shaft 36 and a fixing member 41 such as a C-ring fitted in the groove of the rotor shaft 36.

  FIG. 3 is an exploded perspective view schematically showing the main part of the motor 20. Referring to FIGS. 2 and 3, the permanent magnet 34 is formed in an annular thin plate shape, and has magnetic poles 34a that are alternately different in the circumferential direction C1. Each magnetic pole 34a has the same length in the circumferential direction C1. One end surface 34b of the permanent magnet 34 is orthogonal to the axial direction S1 and faces the permanent magnet 35 side. The other end surface 34 c of the permanent magnet 34 is fixed to one end surface 37 a of the flange 37 using an adhesive or the like.

  The permanent magnet 35 is formed in an annular thin plate shape and has magnetic poles 35a that are alternately different in the circumferential direction C1. Each magnetic pole 35a has the same length in the circumferential direction C1. One end surface 35b of the permanent magnet 35 is orthogonal to the axial direction S1 and faces the permanent magnet 34 side. The other end surface 35c of the permanent magnet 35 is fixed to one end surface 38a of the flange 38 using an adhesive or the like. The outer diameter of the permanent magnet 35 is substantially the same as the outer diameter of the permanent magnet 34.

  The number of poles of the permanent magnet 34 and the number of poles of the permanent magnet 35 are the same. Further, the permanent magnet 34 and the permanent magnet 35 are arranged with a skew angle θ1 as a predetermined angle with respect to the circumferential direction C1. That is, for example, the position of the N pole 34a1 of the permanent magnet 34 and the position of the N pole 35a1 of the permanent magnet 35 opposed to the N pole 34a1 in the axial direction S1 are shifted by a skew angle θ1.

  With the above configuration, the one end surface 34b of the permanent magnet 34 and the one end surface 35b of the permanent magnet 35 are opposed to each other in the axial direction S1. A housing space 42 is formed by the permanent magnets 34 and 35, the rotor shaft 36 and the housing body 30. The stator unit 28 is accommodated in the accommodation space 42. The stator unit 28 is fixed to the housing body 30.

  The stator unit 28 is disposed between the pair of permanent magnets 34 and 35 with respect to the axial direction S1. That is, the pair of permanent magnets 34 and 35 face each other with the stator unit 28 sandwiched in the axial direction S1. The permanent magnet 34 and the stator unit 28 have a predetermined gap G1 in the axial direction S1. Further, the permanent magnet 35 and the stator unit 28 have a predetermined gap G1 in the axial direction S1. Thus, the motor 20 is an axial gap type motor in which the stator unit 28 is opposed to the permanent magnets 34 and 35 with the gap G1 in the axial direction S1.

A portion of the rotor shaft 36 sandwiched between the pair of permanent magnets 34 and 35 is an insertion portion 36d. A stator 44 (to be described later) of the stator unit 28 is inserted into the insertion portion 36d. The insertion portion 36d and the stator unit 28 face each other with a predetermined gap G2 in the radial direction R1.
FIG. 4 is an exploded perspective view of the stator unit 28. 2 and 4, stator unit 28 includes a stator 44 and a receiving member 45 that receives stator 44.

The stator 44 includes an annular stator core 46 and a plurality of coils 47 held by the stator core 46.
The stator core 46 is formed in an annular shape by arranging a plurality of divided cores 48 in the circumferential direction C1, and has an outer peripheral surface 46a and an inner peripheral surface 46b. Each divided core 48 is formed by laminating a plurality of electromagnetic steel plates 49 in the axial direction S1. Each electromagnetic steel plate 49 is a steel plate made into a predetermined shape by press molding. The opposing surfaces of the electromagnetic steel plates 49 adjacent to each other in the axial direction S1 are fixed by caulking, an adhesive, or the like. Thereby, the opposing surfaces of the electromagnetic steel plates 49 adjacent to each other in the axial direction S1 are prevented from peeling off.

3 and 4, illustration of the state in which the electromagnetic steel plates 49 are stacked is omitted.
Each divided core 48 includes a tooth 50 and a pair of wall portions 51 and 52 formed at both ends of the tooth 50 in the circumferential direction C1. The teeth 50 are formed in small pieces extending along the circumferential direction C1. Each wall part 51 and 52 is formed in flat form. A tooth 50 is connected to the central portion of one side surface of the one wall portion 51. The other wall portion 52 is formed in a shape substantially symmetrical to the one wall portion 51 in the circumferential direction C1. A tooth 50 is connected to the central portion of one side surface of the other wall portion 52.

Each wall part 51 and 52 is extended along radial direction R1. One end surfaces of the wall portions 51 and 52 with respect to the axial direction S <b> 1 form one end surface 48 a of the split core 48. Similarly, the other end surfaces of the wall portions 51 and 52 in the axial direction S <b> 1 form the other end surface 48 b of the split core 48.
The wall 51 is in contact with the wall 52 of another divided core 48 adjacent in the circumferential direction C1. Similarly, the wall 52 is in contact with the wall 51 of another split core 48 adjacent in the circumferential direction C1.

  An outer peripheral surface 46a of the stator core 46 is formed by the outer end portion of the wall portion 51 and the outer end portion of the wall portion 52 in the radial direction R1. The outer peripheral surface 46 a is in pressure contact with the inner peripheral surface 30 a of the housing body 30. Thereby, the stator core 46 is press-fitted and fixed to the inner peripheral surface 30 a of the housing body 30. Further, an inner peripheral surface 46 b of the stator core 46 is formed by the inner end portion of the wall portion 51 and the inner end portion of the wall portion 52 in the radial direction R1.

The teeth 50 are arranged at equal intervals in the circumferential direction C1. In the present embodiment, the number of teeth 50 is nine.
A coil 47 is wound around each tooth 50 by concentrated winding. Each coil 47 is wound around the teeth 50 so as to form an annular shape when the teeth 50 are viewed along the circumferential direction C1. Coil 47 of stator 44 includes a U-phase coil, a V-phase coil, and a W-phase coil. In the present embodiment, three U-phase coils, V-phase coils, and W-phase coils are provided. Each coil 47 is electrically connected to the driver 19 (see FIG. 1) via a bus bar (not shown).

  Referring to FIGS. 2 and 4, receiving member 45 is provided to prevent peeling between electromagnetic steel plates 49 adjacent in axial direction S <b> 1. The receiving member 45 is provided to align the divided cores 48. The receiving member 45 is made of a nonmagnetic material such as aluminum. The receiving member 45 has a bobbin shape, and includes a first receiving portion 55, a second receiving portion 56, and a fixing portion 57 that fixes the first receiving portion 55 and the second receiving portion 56. .

  The first receiving portion 55 is formed in an annular shape. The first receiving portion 55 is disposed between one end surface 48 a of each divided core 48 and one permanent magnet 34. The first receiving portion 55 abuts on one end surface 48 a of each divided core 48 and receives this one end surface 48 a, and restricts displacement of each divided core 48 toward the permanent magnet 34. An outer diameter 55 a of the first receiving portion 55 is fitted to the inner peripheral surface 30 a of the housing body 30 and is fixed to the housing body 30. The outer diameter portion 55 a may not be in contact with the housing 30.

  The second receiving portion 56 is formed in an annular shape. The second receiving portion 56 is disposed between the other end surface 48 b of each divided core 48 and the other permanent magnet 35. The second receiving portion 56 is in contact with the other end surface 48b of each divided core 48 and receives the other end surface 48b, and restricts each divided core 48 from being displaced toward the permanent magnet 35 side. The outer diameter portion 56 a of the second receiving portion 56 is fitted to the inner peripheral surface 30 a of the housing body 30 and is fixed to the housing body 30. The outer diameter portion 56 a may not be in contact with the housing 30.

The fixing portion 57 is formed in a cylindrical shape, and is fixed to the inner diameter portion of the first receiving portion 55 and the inner diameter portion of the second receiving portion 56, respectively. The insertion portion 36 d of the rotor shaft 36 is inserted through the fixed portion 57. The fixing portion 57 is located inward of the radial direction R1 with respect to each divided core 48. The fixing portion 57 is surrounded by the inner peripheral surface 46 b of the stator core 46.
With the above configuration, the receiving member 45 is formed with a groove-like space 58 that is partitioned by the first receiving portion 55, the second receiving portion 56, and the fixing portion 57. A stator 44 is accommodated in the groove-shaped space 58. The stator unit 28 is formed by inserting each divided core 48 into the groove-shaped space 58. Further, the divided cores 48 are sandwiched in the axial direction S1 by the first receiving portion 55 and the second receiving portion 56.

Referring to FIG. 2, motor 20 further includes sound absorbing members 61 and 62. The sound absorbing members 61 and 62 are accommodated in the housing 26, and suppress the air vibration generated in the housing 26 from being transmitted to the outside of the housing 26.
The sound absorbing members 61 and 62 are formed using a member having a hollow portion such as glass wool, for example. By reflecting the vibration in the housing 26 by the sound absorbing members 61 and 62, leakage of vibration (sound) of the housing 26 to the outside of the housing 26 is suppressed. The sound absorbing members 61 and 62 may be formed of a material other than glass wool.

  The sound absorbing member 61 is disposed between the end wall 31 of the housing 26 and the flange 37. One side surface 61 a of the sound absorbing member 61 is fixed to the inner side surface of the end wall 31 using an adhesive or the like. The sound absorbing member 61 is formed in an annular shape. The sound absorbing member 61 is disposed so as to close one end of the housing body 30. An inner diameter portion 61 b of the sound absorbing member 61 is adjacent to and surrounds the rotor shaft 36. The outer diameter portion 61 c of the sound absorbing member 61 is in contact with the inner peripheral surface 30 a of the housing body 30.

  The sound absorbing member 62 is disposed between the lid 32 of the housing 26 and the flange 38. One side surface 62a of the sound absorbing member 62 is fixed to the inner side surface of the lid 32 using an adhesive or the like. The sound absorbing member 62 is formed in an annular shape. The sound absorbing member 62 is disposed so as to close the other end of the housing body 30. An inner diameter portion 62 b of the sound absorbing member 62 is adjacent to and surrounds the rotor shaft 36. The outer diameter portion 62 c of the sound absorbing member 62 is in contact with the inner peripheral surface 30 a of the housing body 30.

The sound absorbing members 61 and 62 are opposed to each other with the stator unit 28 sandwiched in the axial direction S1.
2 and 3, in the electric power steering apparatus 1 having the above schematic configuration, when driving power is supplied to the corresponding coil 47 of the stator 44 of the motor 20, the corresponding coil 47 is excited. The As a result, a magnetic field along the circumferential direction C <b> 1 is generated around the excited coil 47. And it acts so that each magnetic field of the coils 47 and 47 adjacent to the circumferential direction C1 may repel.

As a result, a magnetic field directed in the axial direction S1 is generated. As a result, an attractive force and a repulsive force are generated between the stator 44 and the permanent magnets 34 and 35 facing each other in the axial direction S1, and the rotor 27 rotates.
As described above, according to the present embodiment, the one end surface 48 a and the other end surface 48 b of each divided core 48 are sandwiched between the receiving members 45. Thereby, it can suppress reliably by the receiving member 45 that the adjacent electromagnetic steel plates 49 of the split core 48 peel. Therefore, even if the magnetic force acting between the rotor 27 and the stator 44 acts as a periodic force for separating the electromagnetic steel plates 49 from each other, it is possible to suppress (prevent) peeling between the electromagnetic steel plates 49.

For example, in the case of a radial gap type motor in which the stator and the rotor are opposed to each other in the radial direction of the motor and the rotor is rotated using a magnetic flux directed in the radial direction, the magnetic force is an excitation force that vibrates the housing in the radial direction. Acts as As a result, when the housing is deformed in the radial direction, air outside the housing is vibrated, and noise is generated.
On the other hand, according to the present embodiment, when the axial gap type motor 20 is driven, an excitation force as a periodically acting force is generated in the stator 44 along the axial direction S1. This exciting force is a force substantially parallel to the coupling surface of the stator 44 and the housing 26 (the inner peripheral surface 30a of the housing body 30).

  Therefore, the housing 26 can be prevented from being deformed by the above-described excitation force. For this reason, it can suppress that the housing 26 receives the force from the stator 44 and vibrates. Therefore, vibrations of the air around the housing 26 can be suppressed, and noise during driving of the motor 20 can be further suppressed. Furthermore, by fixing the outer peripheral surface 46 a of the stator core 46 to the inner peripheral surface 30 a of the housing 26, it is possible to more reliably suppress peeling between the electromagnetic steel plates 49 of the stator core 46.

In addition, sound absorbing members 61 and 62 are disposed on the end wall 31 and the lid 32 as a pair of end portions of the housing 26. Thereby, it is possible to suppress the vibration of the air inside the housing 26 from being transmitted to the outside of the housing 26. Thereby, the noise at the time of the drive of the motor 20 can be suppressed more reliably.
Further, the permanent magnets 34 and 35 are arranged with a predetermined skew angle θ1 shifted in the circumferential direction C1. Thereby, the cogging torque at the time of rotation of the rotor 27 can be suppressed. Thereby, since vibration of the air around the rotor 27 can be suppressed, noise during driving of the motor 20 can be further suppressed.

As described above, the motor 20 having excellent silence can be realized even when the output torque is large.
The motor 20 is particularly preferably used in a hybrid vehicle using an engine and an electric motor as a power source and an electric power steering apparatus 1 provided in a vehicle (electric vehicle) using an electric motor as a power source. In these vehicles, the operation sound of the power source when running or when stopped is quiet. In such a vehicle, by using the motor 20 excellent in quietness, the quiet feeling given to the vehicle occupant can be further increased.

The present invention is not limited to the contents of the above embodiments, and various modifications can be made within the scope of the claims.
For example, as shown in FIG. 5, the permanent magnet 63 may be fixed to the outer diameter portion of the insertion portion 36 d of the rotor 27. The permanent magnet 63 is formed in a cylindrical shape and has magnetic poles 63a that are alternately different in the circumferential direction C1. Each magnetic pole 63 has the same length in the circumferential direction C1. The number of magnetic poles 63a is the same as the number of magnetic poles 34a. The permanent magnet 63 is disposed with a predetermined skew angle in the circumferential direction C1 with respect to at least one of the permanent magnets 34 and 35. The permanent magnet 63 is surrounded by each coil 47.

In this case, torque can be applied to the permanent magnet 63 fixed to the insertion portion 36d by using the leakage magnetic flux from the stator 44, that is, the magnetic flux that does not contribute to the rotation of the permanent magnets 34 and 35 among the magnetic flux from the stator 44. . Thereby, the output (torque constant) of the motor 20 can be made higher.
Further, instead of the receiving member 45, as shown in FIG. 6, a receiving member 45A having a guide portion 65 for aligning the divided cores 48 may be used. The guide portion 65 is formed on the opposing surfaces 55 b and 56 b of the first receiving portion 55 and the second receiving portion 56. The guide portion 65 includes a plurality of protrusions 66 formed on the first receiving portion 55 and a plurality of protrusions 67 formed on the second receiving portion 56.

  A plurality of protrusions 66 are spaced apart in the circumferential direction C1. Each protrusion 66 extends along the radial direction R1. A split core 48 is inserted between the protrusions 66 adjacent to the circumferential direction C1. The plurality of protrusions 67 are spaced apart in the circumferential direction C1. Each protrusion 67 extends along the radial direction R1. A split core 48 is inserted between the protrusions 67 that are adjacent to each other in the circumferential direction C1.

In this case, the guide portion 65 can exhibit the function of a guide for inserting each divided core 48. Thereby, insertion of each divided core 48 to the receiving member 45 can be performed more easily.
In each said embodiment, although the structure which made the 1st receiving part 55 and the 2nd receiving part 56 annular | circular shaped was demonstrated, it is not limited to this. The 1st receiving part 55 and the 2nd receiving part 56 should just be able to receive the one end surface 48a and the other end surface 48b of each division | segmentation core 48, and may be shapes other than a ring shape.

Further, the positions of the permanent magnets 34, 35, and 63 in the circumferential direction C1 may be aligned. That is, the permanent magnets 34, 35, and 63 may not be provided with a skew. Furthermore, at least one of the sound absorbing members 61 and 62 may be omitted.
In addition, the present invention can be applied to an axial gap type motor provided in a device other than the electric power steering device.

DESCRIPTION OF SYMBOLS 20 ... Axial gap type motor, 26 ... Housing, 27 ... Rotor, 30a ... Inner peripheral surface of housing, 31 ... End wall (end of housing), 32 ... Cover (end of housing), 33 ... Rotor core, 34, 35 ... Permanent magnet, 34a, 35a ... Magnetic pole, 36d ... Insertion part, 44 ... Stator, 45, 45A ... Receiving member, 46 ... Stator core, 46a ... Outer surface of stator core, 47 ... Coil, 48 ... Split core, 48a ... Split One end surface of the core, 48b ... the other end surface of the split core, 49 ... magnetic steel plate, 55 ... first receiving portion, 56 ... second receiving portion, 57 ... fixing portion, 61,62 ... sound absorbing member, 63 ... permanent magnet (insertion) Permanent magnet fixed to the part), C1... Circumferential direction, S1... Axial direction, .theta.1 ... skew angle (predetermined angle).

Claims (5)

A stator including an annular stator core formed by laminating a plurality of divided cores formed by laminating electromagnetic steel sheets in the axial direction, and a plurality of coils wound around each divided core,
A non-magnetic receiver including a first receiving part that receives one end face of each of the split cores in the axial direction, a second receiving part that receives the other end face of each of the split cores, and a fixing part that fixes each of the receiving parts. Members and
A rotor including a pair of annular permanent magnets facing each other with the stator sandwiched in the axial direction, and a rotor core that couples the pair of permanent magnets so as to be integrally rotatable;
An axial gap type motor characterized by comprising: In Claim 1, further comprising an annular housing for accommodating the stator,
An axial gap motor, wherein an outer peripheral surface of the stator core is fixed to an inner peripheral surface of the housing.   3. The axial gap type motor according to claim 2, further comprising a sound absorbing member disposed at at least one end of the housing.   The permanent magnet according to claim 1, wherein each permanent magnet has a plurality of magnetic poles in the circumferential direction, and one of the permanent magnets is in the circumferential direction with respect to the other permanent magnet. The axial gap motor is characterized in that it is disposed at a predetermined angular deviation. In any one of Claims 1-4, the said rotor core contains the insertion part which penetrates the said stator,
An axial gap motor, further comprising a permanent magnet fixed to the insertion portion.

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