JP2011092008A - Rotary electrical machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary electrical machine capable of stably adjusting magnetic resistance and thus having excellent controllability of output characteristics. <P>SOLUTION: The rotary electric machine has a rotor and a stator which oppose to each other. Either of them is divided into at least two portions, i.e. a first portion including an opposite portion opposing the other and a second portion not including the opposite portion opposing the other. The magnetic resistance between the first and second portions can be controlled. The rotary electrical machine can be changed between a state of forming a magnetic flux flow flowing through the pair of first portions adjacent to each other via the second portion and a state of forming a magnetic flux flow transmitting through the opposite portions of the pair of first portions and a space between the opposite portions of the pair of first portions. The second portion moves relative to the first portion so that the magnetic resistance can be adjusted between the first and second portions. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rotating electrical machine having good output characteristics in a wide operation region from high torque low speed rotation to low torque high speed rotation without using field weakening control.

Conventionally, a radial gap type electric motor used as a radial gap type rotating electrical machine as a drive source for electric motorcycles and other general electric motors is a rotor yoke (rotor side) having a rotating shaft supported by its bearings. The yoke) and the yoke of the stator (stator side yoke) are opposed to each other, and the facing surfaces thereof are parallel to the rotation axis.
A plurality of field magnets are arranged in the circumferential direction on the cylindrical inner wall on the opposing surface of the rotor side yoke, and the cylindrical surface of the rotor side yoke is provided on the opposing surface of the stator side yoke. A plurality of teeth are arranged radially so as to face the facing surface. A coil is wound around the plurality of teeth.

That is, in the radial gap type electric motor, the opposing surfaces of the field magnet and the teeth are parallel to the rotation axis, and the gap between the opposing surfaces is formed in a cylindrical shape along the rotation axis. That is, as the name of the radial gap type, the gap is formed in the radiation direction from the rotation axis.
Moreover, although it is a radial gap type electric motor, contrary to the above, the stator side yoke is formed in a cylindrical shape, the rotor side yoke is in a columnar shape, and is disposed in the cylindrical circle of the stator side yoke. There is also an electric motor.

On the other hand, in recent years, attention has been drawn to axial gap type rotating electrical machines in addition to the radial gap type rotating electrical machines.
For example, an axial gap type electric motor as this axial gap type rotating electric machine includes a disk-like rotor-side yoke having a rotating shaft supported by its bearing, and a disk-like fixed around the axis of the rotating shaft. The child side yokes are arranged to face each other.

  A plurality of field magnets are arranged in a circular shape (or an annular shape) along the disk-shaped peripheral portion on the opposing surface of the rotor side yoke, and on the opposing surface of the stator side yoke. A plurality of teeth are arranged in a substantially annular shape along the disk-shaped peripheral portion. A gap is formed between the opposing surfaces of the field magnet and the teeth, and the opposing surface forms a surface orthogonal to the rotation axis (that is, perpendicular to the rotation axis). That is, as the name of the axial gap type, the gap between the opposing surfaces is formed in the direction along the rotation axis, that is, in the axial direction.

  In such an axial gap type electric motor, a rotor (a rotor side yoke on which a field magnet is disposed) and a stator (a coil coil disposed on the stator side yoke) disposed opposite thereto are arranged. The technology that makes the output characteristics of the electric motor variable by changing the distance between the rotor and the stator by displacing one of the cores) in the rotational axis direction, that is, by changing the gap that can adjust the magnetic resistance. Proposed. (For example, refer to Patent Document 1.)

WO2004 / 088886

By the way, the configuration of the above prior art, when the gap capable of adjusting the magnetic resistance between the rotor and the stator is varied, the magnetic field lines are bent or leaked, and the interlinkage magnetic flux passing through the coil tends to vary. Controllability of output characteristics was difficult.
An object of the present invention is to provide a rotating electrical machine capable of stably adjusting a magnetic resistance in view of the above-described conventional situation and thereby having good controllability of output characteristics.

Below, the structure of the rotary electric machine concerning this invention is described.
A rotating electrical machine according to the present invention includes a rotor that includes a magnet and rotates about a rotation axis, and a stator that includes a winding and is disposed to face the rotor. It is divided into at least two parts, a first part including an opposing part facing the child and a second part not including the opposing part, and adjusts the magnetic resistance between the first part and the second part It is configured to be possible. Furthermore, this rotating electrical machine makes the magnetic resistance between the opposed portions of the pair of first parts adjacent to each other larger than the magnetic resistance between each first part and the second part, and increases the N of the magnet. The magnetic flux formed between the poles and the S poles is transmitted through the second part without substantially passing through the space between the opposed parts of the first part adjacent to each other, and through the second part. The state in which the magnetic flux flowing through the pair of the first parts adjacent to each other is formed, and the magnetoresistance between the opposing portions of the pair of the first parts adjacent to each other are expressed by the first part and the second part. The magnetic resistance formed between the north and south poles of the magnet is less than the magnetic resistance between the pair of adjacent first portions, and hardly flows into the second portion. Transmitting the space between the parts, the opposing parts of the pair of first parts and It can be changed to a state in which a magnetic flux is formed that passes through the space between the opposing portions of the pair of first portions, and the second portion moves relative to the first portion, and the first portion The magnetic resistance between the part and the second part can be adjusted.

Preferably, the first part includes the winding, and the second part does not include the winding. Moreover, it is preferable that the said 1st site | part has the said coil | winding between the 1st end surface by the side of the opposing part, and the 2nd end surface on the opposite side to the said opposing part. In this case, it is preferable that the second end surface faces the second portion.
The first part and the second part may be divided, for example, in the direction of magnetic flux flow passing through both of them. Further, for example, the stator may be divided into the first part and the second part outside the winding. Further, for example, the first part and the second part may be divided in a direction in which the rotor and the stator face each other.

Further, the second part may be configured to be movable in a direction intersecting with the direction of magnetic flux flow passing through both the first part and the second part. Further, for example, the second part may be configured to be movable to a position shifted in phase in the rotation direction of the rotor with respect to the first part.
Moreover, it is preferable that the 1st end surface of the said 1st site | part at the opposing part side is formed larger than the 2nd end surface on the opposite side to the said opposing part. In this case, it is preferable that a gap between the pair of first portions adjacent to each other is narrow at the first end face and wide at the second end face. Moreover, it is preferable that the magnetoresistance between the first end surfaces of the pair of adjacent first portions is smaller than the magnetoresistance between the second end surfaces of the pair of adjacent first portions. Furthermore, it is preferable that the magnetoresistance between the first end faces of the pair of first portions adjacent to each other is greater than the magnetoresistance between the first end face and the rotor.

  According to the present invention, it is possible to stably adjust the magnetic resistance between the first part and the second part, and thereby it is possible to provide a rotating electrical machine with good output characteristic controllability.

1 is a side view of an electric motorcycle as an example of a device on which an axial gap type rotating electrical machine that is a rotating electrical machine according to a first embodiment of the present invention is mounted. It is sectional drawing which shows the structure of the axial gap type electric motor (electric motor) used as the basis of this invention with the structure of the rear-end part vicinity of a rear arm. It is a figure which shows the structure seen from the stator of the electric motor, and its periphery rear-wheel side. It is a perspective view which contrasts and shows the schematic structure of the principal part of a stator by the shape disassembled easily intelligible with the rotor arrange | positioned facing a stator, and its rotating shaft. (a)-(f) is a figure explaining the drive principle of an axial gap type electric motor. It is a figure which shows the state which one tooth | gear straddles and faces a N pole magnet and a S pole magnet in the arrangement | sequence which the actual N pole magnet and the S pole magnet adjoined. It is a figure explaining the reason which has a fixed limit in the rotational speed of a normal axial gap type electric motor. It is a figure which shows typically the method of the field weakening control utilized in order to raise the rotational speed of a normal axial gap type electric motor. It is sectional drawing which shows the structure of the axial gap type electric motor in 1st Embodiment with the structure of the rear-end part vicinity of a rear arm. It is an exploded perspective view of the axial gap type electric motor in a 1st embodiment. It is a perspective view which shows the state which the axial gap type electric motor in 1st Embodiment assembled, with a rotation control system. (a), (b), and (c) are reciprocal movements performed with respect to the first stator along the rotational direction of the rotor by the second stator of the axial gap type electric motor in the first embodiment. It is a figure explaining a rotation angle and operation | movement. (a), (b) is a figure explaining the principle of rotation control from the high torque low speed rotation to the low torque high speed rotation of the axial gap type electric motor in 1st Embodiment. (a)-(e) is a figure explaining the gap used as magnetic resistance. It is sectional drawing which shows the structure of the radial gap type electric motor concerning 2nd Embodiment. It is sectional drawing which shows the structure of the radial gap type electric motor concerning 3rd Embodiment. It is a perspective view which shows the structure of the principal part of the axial gap type electric motor concerning one reference form. It is a figure which shows the relationship of the shift | offset | difference of the rotation phase of the 1st rotor at the time of high speed and low torque rotation in the structure of the axial gap type electric motor concerning the said reference form, and a 2nd rotor.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Electric motorcycle equipped with the rotating electric machine of the present invention)
FIG. 1 is a side view of an electric motorcycle as an example of an apparatus on which an axial gap type rotating electric machine that is a rotating electric machine according to a first embodiment of the present invention is mounted. As shown in FIG. 1, the electric motorcycle 1 of this example includes a head pipe 2 at the front upper part of the vehicle body, and a steering shaft (not shown) for changing the vehicle body direction is rotatably inserted into the head pipe 2. Has been.

A handle support portion 4 to which the handle 3 is fixed is attached to the upper end of the steering shaft, and grips 5 are attached to both ends of the handle 3. Further, the grip on the right side (the back side in FIG. 1) which is not visible in the shade in FIG. 1 constitutes a rotatable throttle grip.
A pair of left and right front forks 6 are attached downward from the lower end of the head pipe 2. A front axle 8 that rotatably supports the front wheel 7 is sandwiched in a state of being buffered and suspended at the lower end of the front fork 6.

In the handle support part 4, a meter 9 is disposed in front of the handle 3, a headlamp 11 is fixed below the meter 9, and flasher lamps 12 are provided on both sides of the headlamp 11. (The right side, that is, the flasher lamp 12 on the back side in FIG. 1 is hidden and cannot be seen).
A pair of left and right vehicle body frames 13 that are substantially L-shaped in a side view are extended from the head pipe 2 toward the rear of the vehicle body. The vehicle body frame 13 has a round pipe shape, and extends obliquely downward from the head pipe 2 toward the rear of the vehicle body, and then extends horizontally toward the rear to form a substantially L shape in side view.

A pair of left and right seat rails 14 extend from the rear end of the pair of vehicle body frames 13 obliquely upward and rearward from the rear end. The rear end 14 a of the seat rail 14 is bent rearward along the shape of the seat 15.
A battery 16 is detachably disposed between the pair of left and right seat rails 14. The battery 16 is configured to house a plurality of rechargeable secondary batteries.

Further, in the vicinity of the bent portion of the pair of left and right seat rails 14, a seat stay 17 formed in an inverted U shape is welded obliquely upward toward the front of the vehicle body. The seat 15 is disposed at a portion surrounded by the seat stay 17 and the left and right seat rails 14 so that the front end of the seat 15 can be pivoted up and down.
A rear fender 18 is attached to the rear end of the seat rail 14, and a tail lamp 19 is attached to the rear surface of the rear fender 18. Further, on the left and right sides of the tail lamp 19, flash lamps 21 (the right side, that is, the flasher lamp 21 on the back side of the paper surface in FIG. 1 are hidden and cannot be seen) are provided.

On the other hand, rear arm brackets 22 (only the front side of the drawing is shown in FIG. 1) are welded to the horizontal portion below the seat 15 of the pair of left and right body frames 13, respectively. A front end of 23 is swingably supported via a pivot shaft 24.
A rear wheel 25 as a drive wheel is rotatably supported at the center of the rear end portion 23a of the substantially circular rear arm 23. The rear arm 23 and the rear wheel 25 are buffered and suspended by a rear cushion 26.

  Below the horizontal portion of the pair of left and right body frames 13, a pair of left and right foot steps 27 (only the front side of the drawing is shown in FIG. 1) are provided. Further, on the rear side of the foot step 27, a side stand 28 is supported by the left rear arm 23 so as to be rotatable via a shaft 29. The side stand 28 is biased to the closing side by a return spring 31.

A drive unit including an axial gap type electric motor 32 that is connected to the rear wheel 25 and rotationally drives the rear wheel 25 is mounted in the rear end portion 23a of the rear arm 23.
Here, after describing the configuration and operation of the axial gap type electric motor that is the basis of the present invention, the configuration and operation of the axial gap type electric motor 32 in the first embodiment of the present invention will be described. To do.
(Basic configuration of axial gap type electric motor)
FIG. 2 is a cross-sectional view showing the configuration of the axial gap type electric motor (hereinafter also simply referred to as an electric motor) that is the basis of the present invention, together with the configuration in the vicinity of the rear end portion 23a of the rear arm 23. FIG. 2 shows a cross-sectional view (partial side view) taken along arrow A in FIG. However, the illustration of the rear wheel 25 is omitted.

In FIG. 2, the drive unit 33 is housed in a space formed inside a gear cover 34 that is attached to the right side surface (the upper side surface in FIG. 2) of the rear end portion 20 a of the rear arm 23. The drive unit 33 is formed by integrating an electric motor, a planetary gear reducer 35, a controller 36, and the like.
In FIG. 2, the electric motor includes a rotor 38 that is supported by the rear end portion 20a of the rear arm 23 via bearings 37a and 37b so as to be rotatable about the central axis BO of the bearings 37a and 37b. A substantially annular (or donut-shaped) stator 39 fixed to the inner surface of the rear arm rear end portion 23a is provided so as to face the rotor 38.

As shown in FIG. 2, the rotor 38 has a rotor side yoke 41 (41 a to 41 e). The rotor side yoke 41 forms a substantially frame shape that is convex toward the rear end portion 23 a of the rear arm 23. is doing.
That is, the rotor-side yoke 41 has an annular portion 41a that faces the stator 39, and a tapered portion that extends in a substantially truncated cone shape from the inner peripheral edge portion of the annular portion 41a toward the rear end portion 23a of the rear arm 23. 41b, a first cylindrical portion 41c extending from the extending end of the tapered portion 41b toward the rear end portion 23a of the rear arm 23 along the central axis BO, and an extending end of the cylindrical portion 41c (see FIG. 2, the annular portion 41d extending in the radial direction of rotation from the lower end) toward the central axis BO, and the convex shape along the central axis BO from the inner peripheral edge of the annular portion 41d toward the rear end 23a. Is provided with a second cylindrical portion 41e.

The second cylindrical portion 41e is supported so as to be rotatable about the central axis BO through bearings 37a and 37b, and constitutes a rotating shaft of the rotor 38. Therefore, the rotation axis center of the rotation shaft 43 of the rotor 38 corresponds to the center axis BO of the bearings 37a and 37b.
The rotor 38 includes a plurality of field magnets 42 fixed to the stator-side facing surface of the annular portion 41 a of the rotor-side yoke 41. These field magnets 42 are developed in an annular shape coaxial with the central axis BO along the circumferential direction of the annular portion 41a, and N poles and S poles are alternately arranged. The field magnet 42 is composed of a single magnet in which N poles and S poles composed of a dielectric part that is permanently polarized along the circumference of the same surface of a disk or annulus are alternately magnetized. May be.

At the rear wheel side end of the second cylindrical portion (rotating shaft) 41e of the rotor 38, a toothed rotating shaft 43 is fixed coaxially with the rotor 38 (second cylindrical portion (rotating shaft) 41e). The toothed rotating shaft 43 rotates integrally with the rotor 38.
On the other hand, the planetary gear speed reducer 35 is connected to the toothed rotating shaft 43 and is incorporated in the tapered portion 41 b of the rotor side yoke 41. The planetary gear reducer 35 and the electric motor (rotor 38 and stator 39) partially overlap in the vehicle width direction.

  The planetary gear speed reducer 35 is connected to a rear axle 44 that is arranged coaxially with the toothed rotation shaft 43, and reduces the rotation of the electric motor (rotation of the second cylindrical portion (rotation shaft) 41e). It has a function of transmitting to the rear axle 44 via the toothed rotating shaft 43. A nut 45 is detachably screwed to a front end portion 44 a of the rear axle 44 protruding from the gear cover 34 of the rear axle 44, and the rear wheel 25 shown in FIG. It is fastened by screwing 45 and attached to the rear axle 44.

FIG. 3 is a view showing a configuration of the electric motor as viewed from the stator 39 and the surrounding rear wheel 25 side. 3 corresponds to the right side of the electric motorcycle 1, the left side of the drawing corresponds to the lower side of the vehicle body, the upper side of the drawing corresponds to the rear side of the vehicle body, and the lower side of the drawing corresponds to the front side of the vehicle body.
In FIG. 3 (see also FIG. 2), the stator 39 is fixed to the rear end portion 23a of the rear arm 23. For example, the stator side yoke having a laminated structure in which annular steel plates are laminated in the central axis direction. 46 is provided. The stator side yoke 46 has an inverted C shape centered on the central axis BO, in other words, a circular shape with a part cut away.

  The stator 39 has a substantially rectangular teeth mounting hole of a multiple of 3 formed in the stator side yoke 46 along the circumferential direction, and the teeth mounting hole has a lower part (a side end facing the paper surface in FIG. 3). Are inserted and fixed, and teeth 47 are arranged along the circumferential direction of the stator side yoke 46 at regular intervals (circumferential pitch). The teeth 47 are composed of a laminate of steel plates, and the upper end surface (the front side surface in FIG. 3) faces the field magnet 42 of the rotor 38 with a predetermined gap in the axial direction of the rotation shaft 43. Are arranged to be.

Note that the circumferential pitch connects the center of the upper end surface of each adjacent tooth 47 facing the field magnet 42 and the central axis BO of the bearings 37a and 37b from the center along the upper end surface. It represents the angle between line segments.
Since the shape of the stator side yoke 46 for fixing and holding the teeth 47 has a circular shape with a part cut away around the central axis BO of the bearings 37a and 37b as described above. The teeth 47 whose number is a multiple of 3 are also arranged along the shape of a partially cut circle. Thereby, compared with the case where it arranges in a perfect circle shape, three teeth for three phases (U phase, V phase, W phase) corresponding to the notch part of a circle are missing. Hereinafter, the cutout portion of the circle is referred to as a tooth cutout portion 48.

The stator 39 includes a coil 49 (see FIG. 2) wound around each tooth 47, a mold part 51 in which each tooth 47 and the coil 49 are molded by resin or the like, and an outer periphery of the mold part 51. A plurality of flanges 52 formed on the surface are provided.
The flange 52 includes a bolt hole for attaching the mold part 51 including each tooth 47 and the coil 49 to the rear end part 23 a of the rear arm 23. The stator 39 is fixed to the rear end portion 23a of the rear arm 23 by screwing the bolt 53 inserted into the bolt hole into the rear end portion 23a of the rear arm 23.

  Further, an inverter 54 that is electrically connected to the stator 39 and capable of supplying power to the stator 39 is fixed to the tooth missing portion 48 through an elastic material (not shown) made of rubber or the like. Further, an encoder board 55 is disposed in the tooth missing portion 48, and the encoder board 55 and the inverter 54 are electrically connected with a flexible wire harness 56 (a flexible board or the like may be used). Connected.

On the surface of the encoder board 55, magnetic pole detection elements 57a, 57b and 57c such as Hall sensors are mounted. These magnetic pole detection elements 57a, 57b and 57c are the U phase, V phase and W phase in the electric motor. Are arranged at positions to detect when the electrical angle is 180 ° (for example, the coil current is maximum).
FIG. 4 is a perspective view showing a schematic configuration of a main part of the stator 39 shown in FIG. 3 together with a rotor 38 disposed opposite to the stator 39 and its rotating shaft 43. 4 does not show the coil 49 shown in FIG. 2, the mold part 51 shown in FIGS. 2 and 3, the flange 52 shown in FIG. 3, the inverter 54, the encoder board 55, and the like.

As shown in FIG. 4, the stator side yoke 46 has insertion holes 58 formed in a substantially rectangular shape through which the respective teeth 47 are inserted and fixed. It is arranged in the shape of a circle. A pair of short side inner surfaces 58a and 58b of the insertion hole 58 are respectively directed to the central axis BO.
Further, in each insertion hole 58, a steel plate portion between the inner side surface 58b and the outer peripheral surface 46a is cut and formed on the inner side surface 58b of the stator side yoke 46 on the outer peripheral surface 46a side. Slits 59 that communicate with the outside of the stator side yoke 46 are radially penetrated.

  As described above, the stator side yoke 46 has a pair of teeth 47 of U phase, V phase, and W phase to which an alternating current of two poles and three phases is applied, except for the tooth missing portion 48. Are arranged sequentially. The rotor 38 is provided with an even number of field magnets 42 having N-pole and S-pole pairs at a predetermined arrangement interval corresponding to the arrangement interval of the set of three teeth 47. Of course, as described above, the field magnet 42 is formed by alternately magnetizing N poles and S poles composed of dielectric parts that are permanently polarized along the circumference of the same surface of the disk or ring. You may comprise with two magnets.

  That is, for example, four field magnets 42 having one pole pair are always opposed to each other within the arrangement interval of six teeth 47, or one field magnet having four pole pairs. Are placed so that they always face each other. In addition, within the arrangement interval of the nine teeth 47, six field magnets 42 of one pole pair or one field magnet of six pole pairs are always arranged to face each other. .

A total of 15 teeth 47 shown in FIG. 4 are arranged. This is because three of the teeth 47 are arranged to arrange the encoder board 55 shown in FIG. The teeth 47 are deleted.
Therefore, within the arrangement interval of these 15 teeth 47 (including the three deleted portions), whether an even number of field magnets 42 or one field magnet is used, 12 The magnetic poles of the pole pair are configured to always face each other.
(Driving principle of axial gap type electric motor)
Next, the driving principle of the axial gap type electric motor configured as described above will be described.

  5A to 5F are diagrams for explaining the driving principle of the axial gap type electric motor. In FIG. 6A, an arrow a indicates the rotation direction of the rotor 38, and an arrow b indicates that the direction of the magnetic flux emitted from the N-pole field magnet 42 (hereinafter also simply referred to as magnet 42) is positive. The positive direction of the magnetic flux is shown when the direction of the magnetic flux emitted from the polar magnet 42 is negative. However, the direction of the magnetic flux is not always directed downward as indicated by the arrow b, but may be obliquely downward, but the direction of the downward direction is shown as a whole.

  An arrow c in FIG. 5 (a) indicates an N polarity generated by energization of the coil 49 wound around each tooth 47 of the stator 39 and excited by the teeth 47 (47u, 47v, 47w) which are core materials. The positive direction of the magnetic flux is shown when the direction of the magnetic flux is positive and the direction of the magnetic flux of S polarity is negative. However, the direction of the magnetic flux is not always directed upward as indicated by the arrow c, but may be obliquely upward, but it is shown in the meaning of the upward direction as a whole.

5A to 5F, the U-phase teeth 47 are indicated by 47u, the V-phase teeth 47 are indicated by 47v, and the W-phase teeth 47 are indicated by 47w.
In FIG. 5A, the N-pole magnet 42 is positioned right above the U-phase teeth 47u, and the S-pole magnet 42 is positioned between the V-phase teeth 47v and the W-phase teeth 47w. It shows the state when

In this state, the current to the coil 49 of the U-phase tooth 47u is cut off, the magnetic flux as the tooth 47u is zero, and only the magnetic flux from the N-pole magnet 42 flows in the tooth 47u.
A current for generating a magnetic flux of S polarity flows in the coil 49 of the V-phase tooth 47v, and this magnetic flux of S polarity is excited by the tooth 47v. And the magnet 42 of the same polarity S pole is repelled in the direction of arrow a by the magnetic flux of the S polarity of the excited teeth 47v.

On the other hand, a current for generating an N-polar magnetic flux flows through the coil 49 of the W-phase tooth 47w. The N-polar magnetic flux is excited by the tooth 47w, and the N-polar magnetic flux of the excited tooth 47w An S-polar magnet 42 of opposite polarity is attracted in the direction of arrow a.
The rotor 38 rotates in the direction of arrow a by the torque in the direction of arrow a due to such repulsive force and suction force, and the state shown in FIG. That is, the N-pole magnet 42 is positioned between the U-phase teeth 47u and the V-phase teeth 47v, and the S-pole magnet 42 is positioned directly above the W-phase teeth 47w.

In this state, the direction of the current is switched so as to generate an N-polar magnetic flux in the coil 49 of the U-phase tooth 47u. This N-polar magnetic flux is excited by the tooth 47u, and this excited N-polar magnetic flux is excited. Due to the magnetic flux, the N-polar magnet 42 having the same polarity is repelled in the direction of arrow a.
On the other hand, the coil 49 of the V-phase tooth 47v is switched to generate an S-polarity magnetic flux. This S-polarity magnetic flux is excited by the teeth 47v, and the excited S-polarity magnetic flux reverses the polarity. N pole magnet 42 is attracted in the direction of arrow a.

In this state, the current to the coil 49 of the W-phase tooth 47w is cut off, the magnetic flux as the tooth 47w is 0, and only the magnetic flux from the S-pole magnet 42 flows in the tooth 47w.
Also in this case, the rotor 38 rotates in the direction of the arrow a by the torque in the direction of the arrow a due to the repulsive force and the suction force, and the state shown in FIG. The relationship between the teeth 47 and the magnets 42 in this state is the same as in the state of FIG. 5A, but the correspondence of the teeth 47 to the N-pole and S-pole magnets 42 is shifted one by one in the direction of arrow a. Yes.

That is, the N-pole magnet 42 is positioned immediately above the V-phase teeth 47v, and the S-pole magnet 42 is intermediate between the W-phase teeth 47w and the U-phase teeth 47u in the adjacent three-phase set. Is located.
The currents in the teeth 47v, teeth 47w, and adjacent teeth 47u in the state of FIG. 5 (c) and the polarity of the magnetic flux generated from the coil 49 are the same as the three-phase set of teeth 47u, teeth 47v, And the current in the teeth 47w and the polarity of the magnetic flux generated from the coil 49 are the same.

That is, also in this case, torque in the direction of the arrow a is generated by the repulsive force and the attractive force, and the rotor 38 is rotated in the direction of the arrow a by this torque, and the state shown in FIG. The relationship between the teeth 47 and the magnets 42 in this state is the same as in the state of FIG. 5 (b). In this case as well, the corresponding relationship of the teeth 47 with respect to the N-pole and S-pole magnets 42 is one by one in the direction of arrow a. It is shifted to.
That is, the N-pole magnet 42 is positioned between the V-phase teeth 47v and the W-phase teeth 47w, and the S-pole magnet 42 is directly above the U-phase teeth 47u in the adjacent three-phase set. It will be in the state located.

The currents in the teeth 47v, teeth 47w, and adjacent teeth 47u in the state shown in FIG. 5D and the polarities of the magnetic fluxes generated from the coil 49 are the same as the three-phase set of teeth 47u, teeth 47v, And the current in the teeth 47w and the polarity of the magnetic flux generated from the coil 49 are the same.
Similarly, the state transitions to the state of FIG. 5 (e), and further transitions to the state of FIG. 5 (f), where the N-pole magnet 42 is connected to the W-phase teeth 47w and the adjacent three-phase set. Located in the middle of the U-phase teeth 47u, two sets of three-phase U-phase teeth 47u, V-phase teeth 47v, and W-phase teeth 47w shown on the left in FIG. 5 (a) The driving relationship with the pair of N-pole magnets 42 and the S-pole magnets 42 ends.

  Then, as shown in FIG. 5 (a) again, the driving relationship is completed with the U-phase teeth 47u, the V-phase teeth 47v, and the W-phase teeth 47w shown in the left of the figure. The driving relationship between the two pairs of N pole magnets 42 and the S pole magnets 42 adjacent to the upstream side in the rotation direction of the two pairs of N pole magnets 42 and the S pole magnets 42 is shown in FIG. a) Start as shown in (f).

  5 (a) to 5 (f), the positional relationship between the magnet 42 and the tooth 47 is explained in 6 steps for easy understanding, but in reality, the applied current to the coil 49 has a sine curve. A current to be drawn is sequentially applied to three adjacent teeth 47 that form a pair of two poles and three phases with a predetermined phase difference, and the magnetic flux generated from the coil 49 when energized is applied to the rotor 38 side. Since the magnet 42 rotates, its direction and size change.

Further, the distance between the N pole and the S pole of the magnet 42 in the actual arrangement is closer than that shown in FIGS. 5A to 5F, and there is one for the N pole magnet 42 and the S pole magnet 42. A state in which the teeth 47 face each other also occurs. When one magnet having a plurality of pole pairs is used instead of the even number of magnets 42, the N pole and the S pole are in contact with each other with no gap therebetween.
5 (a) to 5 (f), the driving relationship between all three-phase one set of teeth 47 and two pairs of magnets 42 is also in cooperation with adjacent teeth and magnets. That is, two teeth in one set of three-phase teeth 47 and one tooth in one set of three-phase one teeth 47 become the next three-phase one set, and one of the two pairs of magnets 42 One magnet in the pair of two magnets 42 adjacent to the magnet then becomes a pair of magnets, and sequentially changes in the rotation direction.

The switching of the current for switching the magnetic flux direction of the coil and the application timing thereof are the detection of the rotational positions of the N pole magnet 42 and the S pole magnet 42 by the magnetic pole detection elements 57a, 57b and 57c shown in FIG. This is performed by control from the inverter 54 based on the detection.
As described above, in the axial gap type motor, a magnetic circuit is formed between the rotor 38 and the stator 39, and each tooth 47 is provided via the coil 49 wound around each tooth 47 of the stator 39. By sequentially switching the excitation with respect to the N pole and S pole of the magnet 42 on the rotor 38 side, the repulsive force and the attractive force against the excitation of each tooth 47 of the magnet 42 on the rotor 38 side are used to rotate the magnet. The child 38 is rotated.

  FIG. 6 is a diagram showing a state where one tooth 47 is opposed to the N-pole magnet 42 and the S-pole magnet 42 in an arrangement in which the actual N-pole magnet 42 and the S-pole magnet 42 are close to each other. . In this figure, the arrow a indicates the direction of rotation of the rotor 38. The directions of the magnetic flux flowing between the N-pole magnet 42 and the S-pole magnet 42 are indicated by arrows G1, G2, and G3. This state is a state that occurs in the middle of each of the transitions shown in FIGS.

  In FIG. 6, a current flows in the coil 49 wound around the teeth 47 on the stator 39 in the counterclockwise direction as viewed from above, as indicated by an arrow E. The magnetic flux generated in the magnetic field and excited by the teeth 47 flows as indicated by an arrow G4, and intersects with the magnetic flux flowing between the N-pole magnet 42 and the S-pole magnet 42. Also in this case, the N-pole magnet 42 repels, the S-pole magnet 42 is attracted, and torque in the direction of arrow a is generated in the rotor 38.

In FIG. 6, when the position of the magnet 42 with respect to the tooth 47 is switched and the left magnet 42 N pole and the right magnet become S, the direction of the current flowing through the tooth 47 is opposite to the arrow E, that is, in the upper part of the figure. It changes in the clockwise direction when viewed from the side.
By the way, in the electric motor in the above basic configuration, there is a restriction on the rotational speed, and the rotational force does not increase beyond a certain limit. When converted to the speed of a motorcycle, about 20 km per hour is the limit in order to produce torque that does not cause a problem with the vehicle shown in FIG. However, it goes without saying that this varies depending on the tire diameter, the gear ratio of the drive system gear system, the motor specifications, and the like.

  FIG. 7 is a diagram illustrating the reason why there is a certain limit to the rotation speed of a normal electric motor. The state shown in FIG. 7 shows the position of the N-pole magnet 42 and the V-phase teeth 47v shown in FIG. 5C and the vicinity thereof. In FIG. 7, only the coil 49 of the V-phase teeth 47v is shown, and the other teeth coils are not shown. As described with reference to FIG. 5, when the magnet 42 is directly above the teeth 47, no current is applied to the coil 49.

  In FIG. 7, the rotor 38, the stator 39, and the teeth 47 (47u, 47v, 47w) are soft magnetic materials, and the distance d between the facing surfaces of the magnet 42 and the teeth 47 is very close. Spatial magnetoresistance is low. Therefore, the magnetic flux flowing between the N-pole magnet 42 (N) and the S-pole magnet 42 (S) is a magnetic flux flow 61 and the other is a magnetic flux flow 62, and the magnetic pole of the magnet 42, the rotor 38 and the teeth 47. And in the stator 39. As a result, a magnetic flux having a large magnetic flux amount obtained by joining the two magnetic flux flows 61 and 62 flows into the coil 49 of the tooth 47v via the teeth 47v disposed in the coil 49.

  While the rotor 38 is rotating in the direction of arrow a, the magnetic flux flowing in the coil 49 in the above state crosses the coil 49, so that a current is generated in the coil 49 according to Faraday's law of electromagnetic induction. The current generated in the coil 49 generates an S-polar magnetic flux from the coil 49 upward. That is, the S-polarized magnetic flux formed in the coil 49, that is, in the teeth 47v by the current generated in the coil 49 works to attract the N-pole magnet 42 (N).

  That is, a resistance force (magnetic resistance) is applied to the rotation of the rotor 38. The faster the rotor 38 rotates, the higher the speed at which the magnetic flux in the coil 49 where the magnetic flux flows 61 and 62 are merged crosses the coil 49. The higher the speed at which the magnetic flux crosses the coil 49 is, the larger current is generated in the coil 49 To do. As the generated current increases, the amount of S-polarized magnetic flux formed in the teeth 47v by this current increases and the magnetic resistance to the rotor 38 increases.

Eventually, the increase in the rotational force of the rotor 38 and the magnetic resistance are balanced. This equilibrium state is the limit point of the rotational speed described above. Of course, if the power is increased, the limit point is extended, but the power consumption for that purpose increases geometrically, which is not a good idea.
A field-weakening control method is known as means for eliminating the weak point of the rotational characteristics of the axial gap type electric motor and increasing the rotational force, that is, shifting from high torque low speed rotation to low torque high speed rotation.

FIG. 8 is a diagram schematically showing a field-weakening control method. As described with reference to FIG. 7, in the state where no current is applied to the coil 49 when the N-pole magnet 42 (also in the case of the S-pole magnet 42) is directly above the teeth 47, the rotor 38 When the rotation goes up, a large resistance is applied to the rotation.
However, as shown in the figure, an appropriate current is applied to the coil 49 in the direction indicated by the arrow E (the opposite direction in the case of the S-pole magnet 42) when the N-pole magnet 42 is directly above the teeth 47. As a result, an N-polar magnetic flux is generated in the direction indicated by the arrow G4 in the tooth 47 (the opposite direction in the case of the S-pole magnet 42).

The magnetic flux generated from the coil serves to weaken the N-polar magnetic flux directed from the N-pole magnet 42 to the teeth 47 as indicated by the arrow G2. That is, since the magnetic flux flows 61 and 62 shown in FIG. 7 are weakened, the magnetic resistance is reduced and the rotational force is increased accordingly. That is, low torque and high speed rotation can be obtained.
This field weakening control method is an alternating method applied to the three-phase teeth 47 of U phase, V phase, and W phase that are applied at a timing when the current becomes zero when the electromagnet 42 shown in FIG. A new current that is out of phase with respect to the phase of the current, that is, a current that generates magnetic flux in a direction that weakens the magnetic flux from the electromagnet 42 to the coil at the timing when the current becomes zero (for rotational driving) ( Torque generation) Apply to the coil in addition to the current. That is, a current that does not contribute to the rotational torque itself is newly applied.

In addition, as a method for obtaining the low torque and high speed rotation of the electric motor as described above, there is a method of widening the gap between the rotor and the stator in the rotation axis direction, that is, widening the magnetic gap between the rotor and the stator. That was mentioned above.
However, the inventor of the present invention has realized that the flow of magnetic flux is unstable in the magnetic gap between the rotor and the stator that are rotating relative to each other. The present invention begins when the inventor has realized that the flow of magnetic flux flow is unstable in the magnetic gap between the rotor and the stator that are rotating relative to each other as described above.

The inventor has found that the flow of the magnetic flux flow can be controlled by finding a place where the flow of the magnetic flux flow is in order and forming a changeable magnetic gap there. As a result, controllability of output characteristics can be improved. This will be described below.
(Configuration and operation of axial gap type electric motor according to the first embodiment of the present invention)
Next, the configuration and operation of the axial gap type electric motor according to the first embodiment of the present invention will be described based on the basic configuration and driving principle of the axial gap type electric motor as described above.

FIG. 9 is a sectional view showing the configuration of the axial gap type electric motor according to the first embodiment together with the configuration in the vicinity of the rear end portion of the rear arm. In FIG. 9, the same components as those in FIG. 2 are given the same numbers as in FIG.
FIG. 10 is an exploded perspective view of the axial gap type electric motor according to the first embodiment. Hereinafter, the configuration of the axial gap type electric motor (hereinafter simply referred to as an electric motor) of this example will be described with reference to FIGS. 9 and 10.

The electric motor 70 of this example first includes a rotor 71. The rotor 71 is configured to rotate in a disk shape around the rotation shaft 72. The rotor 71 has the same configuration as the rotor 38 shown in the basic configuration of FIGS.
That is, in FIG. 10, the rotor 71, the rotating shaft 72, the rotor side yoke 73, the annular portion 74, the tapered portion 75, the first cylindrical portion 76, the annular portion 77, the second cylindrical portion 78, and the field 2 and 4, the magnet 79 includes the rotor 38, the rotating shaft 41e, the rotor-side yoke 41, the annular portion 41a, the tapered portion 41b, the first cylindrical portion 41c, the annular portion 41d, 2 cylindrical portions (rotating shafts) 43 and field magnets 42 are the same.

A stator (stator) 88 is disposed opposite to the rotor 71 (more specifically, a surface on which a plurality of field magnets 79 are disposed). The stator 88 is divided into two parts, a first stator 83 and a second stator 87.
The first stator 83 includes a first stator core 80 having a plurality of first teeth 81 held by a holding member (not shown). The first teeth 81 are arranged with one end surface 81 a facing the rotor 71 along the axial direction of the rotation shaft 72. That is, the first tooth 81 has a facing portion that faces the rotor 71. These first teeth 81 are provided with windings 82 around side surfaces 81c excluding both end surfaces (81a, 81b) thereof.

  The first teeth 81 are formed such that the end surface 81a (first end surface) on the facing portion facing the rotor 71 is larger than the end surface 81b (second end surface) on the opposite side to the facing portion. ing. As a result, the gap between the pair of first teeth 81 adjacent to each other is narrow on the side of the facing surface 81 a (first surface) facing the rotor 71, and the end surface 81 b on the opposite side of the facing portion. It is wider on the (second end face) side.

  The plurality of first teeth 81 in a state where the winding 82 is applied are molded integrally with the winding 82 to form a first stator 83 having an annular shape as a whole. The torque generation drive current applied to each winding (coil) 82 of the first tooth 81 of the first stator 83 is controlled by the same method as described in FIG. 5, that is, field weakening control. The torque generation of the electric motor is controlled by current control using a basic driving method that is not performed.

Further, the second stator 87 does not have a facing portion that faces the rotor 71, and the same number of second teeth 84 as the first teeth 81 are held by the holding member 85, and the second stator 87 itself is the first one. 2 stator cores (87).
The second teeth 84 of the second stator 87 have one end 84 a opposite to the end surface 81 a facing the rotor 71 of the first tooth 81 of the first stator 83. It is arranged to face the end surface 81b (second end surface) of the.

The other end portion 84 b of the second tooth 84 is press-fitted into a plurality of mounting holes 86 formed in the annular holding member 85 and fixed.
A second stator 87 is formed by the second teeth 84 and a holding member 85 that is press-fitted and fixed to the mounting holes 86. In addition, it is preferable that the second teeth 84 and the holding member 85 are integrally molded. In this example, the second teeth 84 and the holding member 85 are also molded, but the mold is not shown in FIG.

  FIG. 11 is a perspective view showing a state in which the electric motor 70 having the above configuration is assembled together with the rotation control system. In FIG. 11, the same components as those in FIG. 10 are denoted by the same reference numerals as those in FIG. Also in FIG. 11, the illustration of the mold of the first stator 83 and the second stator 87 is omitted. Further, in the holding member 85 of the second stator 87 shown in FIG. 11, a slit 89 (see the slit 59 in FIG. 4) not shown in FIG. 10 is shown.

As shown in FIG. 11, in the electric motor 70 shown in the exploded view of FIG. 10, the rotor 71, the first stator 83, and the second stator 87 face each other with a slight gap therebetween in the direction of the rotation axis. Are arranged sequentially.
As the name suggests, the first stator 83 is fixed to the rear end 23a of the rear arm 23 shown in FIG. On the other hand, the second stator 87 is not completely fixed and rotates slightly with respect to the first stator 83, as will be described in detail later.

As shown in FIG. 11, the rotation mechanism is such that the gear engaging tooth portion 90 formed on a part of the side surface of the holding member 85 of the second stator 87 is a small-diameter gear of the reduction gear 91 of the rotation control system. It is formed by meshing.
The large-diameter gear of the reduction gear 91 is engaged with the small-diameter gear of the next-stage reduction gear 92, and the large-diameter gear of the reduction gear 92 is engaged with the small-diameter gear of the third-stage reduction gear 93. The large-diameter gear of the reduction gear 93 meshes with a worm gear 95 fixed at the tip of the rotating shaft of the motor 94.

  The motor 94 is connected to a drive pulse voltage output terminal (not shown) of a controller 97 to which circuit drive power is supplied from a power supply 96, and is driven to rotate in both forward and reverse directions. The forward and reverse rotations by the motor 94 are converted to a right angle by the worm gear 95 and reduced in speed and transmitted to the large-diameter gear of the reduction gear 93. Accordingly, the speed is further reduced in three stages and transmitted to the gear engaging tooth portion 90 formed on the holding member 85 of the second stator 87.

Accordingly, the second stator 87 is configured to be slightly movable in the rotation direction of the rotor 71 with respect to the first stator 83. That is, the second stator 87 reciprocates steplessly and intermittently with a narrow rotation angle. In other words, the second stator 87 rotates slightly steplessly and intermittently in both forward and reverse directions along the rotation direction of the rotor 71.
12 (a), 12 (b), and 12 (c) explain the rotation angle and operation of the reciprocating movement performed by the second stator 87 with respect to the first stator 83 along the rotation direction of the rotor 71. It is a figure to do. In FIGS. 12A, 12B, and 12C, the displacement state of the second teeth 84 of the second stator 87 relative to the first teeth 81 of the first stator 83 is shown in an easily understandable manner. The winding 82, the slit 89, the gear engaging tooth 90, the rotation control system, etc. shown in FIG. 11 are not shown.

FIG. 12A shows the positional relationship of the second teeth 84 of the second stator 87 with respect to the first teeth 81 of the first stator 83 corresponding to the high-torque low-speed rotation of the electric motor 70 shown in FIG. Show. In this example, this positional relationship is used as a reference position.
Due to the above-described rotation of the second stator 87, the second tooth 84 is moved from the reference position shown in FIG. 12A, that is, the position facing the first tooth 81 to the intermediate position shown in FIG. Through the position, the rotor 71 rotates (reciprocates) within a narrow angle to the maximum movement position shown in FIG. 12 (c), that is, a position just between the first teeth 81 and 81, along the rotation direction indicated by the arrow a. Movement) is possible. Note that the intermediate position shown in FIG. 12 (b) indicates an arbitrary position of stepless and intermittent rotation.

FIGS. 13A and 13B are diagrams for explaining the principle of rotation control from high torque low speed rotation to low torque high speed rotation of the electric motor 70 of this example.
In FIGS. 13 (a) and 13 (b), the winding 82 and the mold wound around the first tooth 81 are not shown for easy understanding. Similarly, the mold of the second teeth 84 and the holding member 85 is not shown.

FIG. 13 (a) shows a state during high-torque low-speed rotation in which the second tooth 84 shown in FIG. 12 (a) is in a position facing the first tooth 81, and FIG. FIG. 12 (c) shows a state at the time of low-torque high-speed rotation in which the second teeth 84 shown in FIG. 12 (c) are located at an intermediate position between the pair of adjacent first teeth 81 and 81.
FIG. 13A shows that the i-th magnet 79i of the rotor 71 faces the i-th first tooth 81i of the first stator 83 on the stator side, and the first tooth thereof. A state is shown in which the i-th second tooth 84i of the second stator 87 on the stator side is directly facing 81i. That is, the same state as in FIG.

  In FIG. 13B, the positional relationship between the magnet 79i of the rotor 71 and the first tooth 81i of the first stator 83 is not changed, and the second tooth 84i of the second stator 87 is the first. This shows a state in which the first tooth 81i of the stator 83 and the other first tooth 81i + 1 adjacent thereto are located in the middle. That is, it shows the same state as FIG.

  In FIG. 13A, the annular portion 74 of the rotor-side yoke 73 in the rotor 71, the first teeth 81 (81i-1, 81i, 81i + 1) of the first stator 83, and the second teeth of the second stator 87. The second teeth 84 (84i-1, 84i, 84i + 1) and the holding member 85 are strongly permeable, and the magnetic resistance between the opposed surfaces of the magnet 79 (79i-1, 79i, 79i + 1) and the first tooth 81 is large. h and the magnetic resistance k between the opposed surfaces of the first tooth 81 and the second tooth 84 are very close and low.

  As described above, since the end surface 81a (first end surface) facing the rotor 71 of the first tooth 81 is formed larger than the other end surface 81b (second end surface), Between the pair of first teeth 81 adjacent to each other, between the end faces 81a facing the rotor 71 (between the facing portions), a magnetic resistance j that is extremely smaller than the magnetic resistance between the other end faces is formed. The magnetic resistance j is larger than the magnetic resistance h with the rotor 71 described above. That is, these magnetic resistances have a relationship of “h≈k <j”.

  Therefore, the magnetic flux formed between the magnet 79i (assuming the N pole) and the adjacent magnet 79i-1 (being the S pole) hardly transmits the magnetic resistance j, and the magnetic resistance h and the first teeth 81i. , The magnetic resistance k, the second tooth 84i, the holding member 85, the second tooth 84i-1, the magnetic resistance k, the first tooth 81i-1, the magnetic resistance h, and the strong magnetic flux passing through the annular portion 74. A stream 98a is formed. That is, a magnetic flux flow 98a flowing through a pair of first teeth 81i and 81i-1 adjacent to each other is formed via the second stator 87.

  Further, the magnetic flux formed between the magnet 79i (N pole) and the other adjacent magnet 79i + 1 (S pole) hardly transmits the magnetic resistance j, so that the magnetic resistance h, the first tooth 81i, the magnetic resistance k, The second tooth 84i + 1, the holding member 85, the second tooth 84i + 1, the magnetic resistance k, the first tooth 81i + 1, the magnetic resistance h, and the strong magnetic flux flow 98b that passes through the annular portion 74 are formed. That is, the magnetic flux flow 98b flowing through the pair of first teeth 81i and 81i + 1 adjacent to each other is formed via the second stator 87.

These phenomena also occur when the magnet 79i is not an N-pole magnet but an S-pole magnet, and only the direction of the magnetic flux flow is reversed, and the magnet 79, the first tooth 81, and the second tooth are related to each other. 84, the holding member 85, and the strong magnetic flux flowing through the annular portion 74 are formed.
As described above, this strong magnetic flux flow becomes a magnetic resistance, and the electric motor 70 has an early limit on the transition from the high torque low speed rotation to the low torque high speed rotation. In addition, as described above, there is a field-weakening control method for extending the limit value.

However, in this example, as described in FIGS. 11 and 12A, 12B, and 12C, the second teeth 84 are adjacent to each other from a reference position facing the first teeth 81. The first teeth 81 and 81 can be rotated (reciprocated) along the rotation direction indicated by the arrow a of the rotor 71 within a narrow angle up to a maximum movement position just between the first teeth 81 and 81.
Now, it is assumed that the second tooth 84 is rotated from the reference position shown in FIG. 13 (a) to the maximum movement position shown in FIG. 13 (b). At this time, a magnetic resistance m larger than the magnetic resistance k when facing the front is formed in the facing portion between the first tooth 81 and the second tooth 84, and the second tooth 84 is further from the holding member 85. Also, the magnetic resistance n larger than the magnetic resistance m between the first tooth 81 and the second tooth 84 is formed between the first tooth 81 and the holding member 85. Is done.

  That is, there is a relationship of “m <n”. n can be ignored with respect to m. Therefore, in the state shown in FIG. 13 (b), the second tooth is just in the middle position between the first tooth 81 and the other first teeth 81 adjacent thereto. When the tooth 84 moves, the second tooth and the end surface 81b (second end surface) opposite to the opposite end surface 81a (first end surface) facing the rotor 71 of the first tooth. It can be said that the magnetic resistance formed in is m.

  As described above, since the end surface 81a facing the rotor 71 of the first tooth 81 is larger than the other end surface 81b, it is between the pair of adjacent first teeth 81. In FIG. 13 (b), the magnetic resistance j formed between the facing portions facing the rotor 71 (between the end faces 81a) is extremely small. In the state shown in FIG. A 2m "relationship is formed.

  That is, the shortest distance formed between the second tooth and the end surface 81b (second end surface) opposite to the end surface 81a (first end surface) facing the rotor 71 of the first tooth. More than (magnetic resistance m), it faces the rotor 71 of the other first tooth 81 adjacent to the end surface 81a (opposing portion) facing the rotor 71 of the first tooth 81 and the first tooth 81. It can be said that the distance (magnetic resistance j) formed between the end surface 81a (opposing portion) is small.

  Then, by entering this state, that is, when the magnetic resistance between the members forms a relationship of “h <j <m <n”, as shown in FIG. N pole) and the magnetic flux formed between other adjacent magnets 79i-1 (S pole) are also held by the first tooth 81i to the second tooth 84i-1 by the magnetic resistance m and the magnetic resistance n. The weak magnetic flux flow 99 a that passes through the first tooth 81 i, the magnetic resistance j, the first tooth 81 i-1, and the annular portion 74 is formed without substantially flowing through 85. That is, the light passes through the space between the opposing portion (end surface 81a) of the pair of adjacent first teeth 81i and 81i-1 and the opposing portion (end surface 81a) of the pair of first teeth 81i and 81i-1. A magnetic flux flow 99a is formed.

  Further, the magnetic flux formed between the magnet 79i (N pole) and another adjacent magnet 79i + 1 (S pole) is also held by the first tooth 81i to the second tooth 84i + 1 by the magnetic resistance m and the magnetic resistance n. The weak magnetic flux 99b that passes through the first teeth 81i, the magnetic resistance j, the first teeth 81i + 1, and the annular portion 74 is formed without substantially flowing through the member 85. That is, the magnetic flux flow 99b that passes through the space between the opposing portion (end surface 81a) of the pair of adjacent first teeth 81i and 81i + 1 and the opposing portion (end surface 81a) of the pair of first teeth 81i and 81i + 1. It is formed.

Thus, the magnetic flux from the magnet 79 hardly traverses the winding 82 of the first tooth 81 (not shown), and the magnetic resistance in the rotating direction of the rotor 71 due to this magnetic flux crossing the winding 82 is reduced. Since it is released, high speed rotation is possible.
Similarly, since the magnetic flux from the magnet 79 hardly flows into the winding core portion of the first tooth 81, it is generated between the first tooth 81 energized in the winding 82 and the magnet 79. Torque to the rotating rotor 71 is reduced. That is, low torque high speed rotation is realized.

Here, a space for forming the above-described magnetic resistance, that is, a gap (j, k, m, n, etc. in FIG. 13) serving as the magnetic resistance will be described. The gap serving as the magnetic resistance is air in the middle of the path through which the magnetic flux flows or a magnetic resistance space equivalent to air. The gap (hereinafter simply referred to as the gap) that becomes the magnetoresistance will be further described.
FIGS. 14A to 14E are views for explaining the difference between the contact area and the gap for changing the magnetic resistance between the two members. In general, when a magnetic flux flowing out of a magnet is about to flow between two members made of a magnetic material, it is known that if the flow of the magnetic flux is secured even partly, the magnet will not emit an excess amount of magnetic flux. ing.

When the above two members are completely separated by a gap, the magnet will flow from a place where it is most likely to flow, that is, a place where the gap is narrow, trying to flow a magnetic flux.
FIG. 14A shows a state where two magnetic bodies 101 and 102 having an L-shaped cross section are in close contact with each other. The magnetic body 101 has an area A in the longitudinal section of the main body and an area B in the longitudinal section of the protrusion. The magnetic body 102 has an area D in the longitudinal section of the main body portion and an area DB in the longitudinal section of the protruding portion. And the area of the horizontal surface of these protrusion parts is the same area C, respectively.

Here, it is assumed that area A = area D = area C = 200 S and area B = 50 S. Then, it is assumed that the magnetic flux 103 emitted from the magnet (not shown) flows from the magnetic body 101 toward the magnetic body 102.
Here, as shown in FIG. 14 (b), the two magnetic bodies 101 and 102 are in the area B portion of the longitudinal section and the area DB portion of the longitudinal section while keeping the area C portion of the horizontal plane in sliding contact. It is assumed that the distances a and b (a = b) are relatively moved apart.

Then, the magnetic flux flow 103 flowing into the main body having the area A = 200S of the magnetic body 101 is saturated at the area B of the longitudinal section because the gap b is formed between the two magnetic bodies 101 and 102. , Only the magnetic flux flowing through the area B = 50S. This magnetic flux flow 103 flows into the magnetic body 102 via the sliding contact surface C1 (area C1 = 150S, B <C1).
Next, as shown in FIG. 14 (c), the two magnetic bodies 101 and 102 are further in sliding contact with the area C of the horizontal plane, and the area B of the longitudinal section and the area DB of the longitudinal section. It is assumed that the portions are relatively separated by distances 2a and 2b. Also in this case, the magnetic flux that is saturated in the area B of the longitudinal section becomes only the magnetic flux that flows in the area B = 50S, and passes through the sliding contact surface C2 (area C2 = 100S, B <C2). Flow into.

That is, there is no change in the magnetoresistance between FIG. 14 (b) and FIG. 14 (c). That is, the space of the distances a, b or 2a, 2b that are separated in the direction of magnetic flux flow between the two magnetic bodies 101 and 102 has no change in magnetoresistance even if the distance changes (the magnetoresistance is not variable). It is not a space that forms a magnetic resistance. That is not a gap.
Here, as further shown in FIG. 14 (d), the two magnetic bodies 101 and 102 have the area B portion of the longitudinal section and the area DB of the longitudinal section while keeping the area C portion of the horizontal plane in sliding contact. It is assumed that the portions are relatively moved apart by distances 3.5a and 3.5b. At this time, the area C portion of the horizontal plane is the sliding contact surface C3 = 25S. That is, B> C3. Therefore, the magnetic flux flow 103 is saturated at the sliding contact surface C3 and flows into the magnetic body 102 side by an area of 25S.

That is, the magnetic resistance between the two magnetic bodies 101 and 102 changes only when the sliding surface of the sliding surface C becomes smaller than the area B of the longitudinal section of the protruding portion of the magnetic body 101. That is, the magnetoresistance changes with the change in the area of the sliding contact surface between the two members.
The change in the magnetic resistance in FIGS. 14C to 14D is due to the change in the area of the sliding contact surface C (change from C2 to C3), and the change in the separation distance between the two members (2a and 2b). → Changes between 3.5a and 3.5b) That is, the changed separation distances 3.5a and 3.5b between the two members are not still gaps.

Further, FIG. 14 (e) shows that the two magnetic bodies 101 and 102 are relatively separated from each other by a distance 5a and a distance 5b in the area B portion of the longitudinal section and the area DB portion of the longitudinal section. The sliding contact surface C3 shown in (d) is completely separated from the sliding contact, and is shown separated by a distance C4.
As described above, when the two members are completely separated by the gap, the magnetic flux flow of the magnet flows most easily, that is, at the narrowest distance C4. That is, the magnetoresistance is generated at the distance C4, and this distance C4 is the magnetoresistance gap. That is, the magnetic resistance changes in accordance with the change in the distance at the distance C4.

In other words, the distance C4 is a gap for changing the magnetic resistance, but the distances 5a and 5b are not spaces for changing the magnetic resistance, that is, not a gap. In this example, what is described as a gap is a portion that forms the distance C4 as described above.
In the present embodiment, as described above, the stator is divided into at least two parts, and the other part is arranged with respect to one part in the rotation direction of the rotor, that is, in the core wound with the winding from the rotor. By moving in a direction perpendicular to the direction of the magnetic flux flowing through the variable gap, a variable gap is formed, whereby the output characteristics of the rotating electrical machine can be greatly varied without consuming electric power that does not contribute to torque.
(Configuration of Radial Gap Electric Motor According to Second Embodiment of the Present Invention)
FIG. 15 is a cross-sectional view showing a configuration of a radial gap type electric motor according to the second embodiment.

In the drawing, the components having the same functions as those in FIG. 10 are given the same reference numerals as those in FIG.
As shown in the figure, this radial gap type electric motor includes a cylindrical rotor 73 that rotates around a rotation shaft (indicated by a rotation center 117 in the figure), and a cylindrical inner side of the rotor 73. Cylindrical first stator core having a plurality of first teeth 81 that are disposed so that one end surface 81a is opposed to the rotor 73 and windings 82 are provided around the side surfaces excluding both end surfaces 81a and 81b. 83.

Further, one end portion 84 a is disposed opposite to the end surface of the first stator core 83 opposite to the end surface facing the rotor 73 of the first tooth 81, and the other end portion 84 b is held by the holding member 85. A second stator core 87 having a plurality of second teeth 84 is provided.
In this radial gap type electric motor, the second stator core 87 is generated by energizing the winding 82 of the first stator core 83 and is perpendicular to the direction of the magnetic flux flowing through the first teeth 81, that is, Moves clockwise or counterclockwise in the figure. Thereby, field control similar to that described in FIGS. 13A and 13B is possible.
(Configuration of radial gap type electric motor according to the third embodiment of the present invention)
FIG. 16 is a cross-sectional view showing a configuration of a radial gap type electric motor according to the third embodiment.

In the same figure, the components having the same functions as those in FIG. 10 are given the same numbers as those in FIG.
As shown in the figure, this radial gap type electric motor includes a columnar or cylindrical rotor 73 that rotates about a rotation shaft 72 and one side of the rotor 73 in the radiation direction outside the rotor 73. A first stator core 83 is provided that includes a plurality of first teeth 81 that are arranged to face the end surface 81a and that have windings 82 around the side surfaces excluding both end surfaces 81a and 81b.

Furthermore, one end portion 84a is disposed opposite to the end surface 81b opposite to the end surface 81a facing the rotor 73 of the first teeth 81 of the first stator core 83, and the other end portion 84b is used as a holding member. A second stator core 87 having a plurality of second teeth 84 held by 85 is provided.
In this radial gap type electric motor, the second stator core 87 is generated by energizing the winding 82 of the first stator core 83 and is perpendicular to the direction of the magnetic flux flowing through the first teeth 81, that is, Moves clockwise or counterclockwise in the figure. Thereby, field control similar to that described in FIGS. 13A and 13B is possible.

FIG. 17 is a diagram illustrating a configuration of a main part of an axial gap type electric motor according to one reference embodiment. FIG. 17 shows only the rotor of the axial gap type electric motor of this example.
As shown in FIG. 17, the rotor 108 of the present example first includes a plurality of magnetic bodies 111 fixed to the annular portion 109 of the rotor yoke of the first rotor 108-1.

Next, the same number of magnetic united magnets 114 as the magnetic body 111 are arranged on a holding rotating member (not shown) so as to be almost in sliding contact with the rotation surface of the magnetic body 111, and the first rotor 108-1. A second rotor 108-2 is provided that is configured to engage with the same shaft and rotate in cooperation with the first rotor 108-1.
The magnetic united magnet 114 is formed by overlapping a magnetic body 112 disposed facing the magnetic body 111 side and a field magnet 113 disposed facing the stator side (not shown). ing.

The stator disposed opposite to the rotor 108 is a stator having the same configuration as the stator 39 shown in FIGS. 3 and 4.
As a result, the magnetic flux of the field magnet 113 is converged by the combined magnetic body 112 and the magnetic body 111 facing the upper part of the magnetic flux from one of the magnetic poles. It is converged by the magnetic body 112 facing the lower portion 109 and the adjacent magnetic body 111 and the magnetic body 111, and the flow is also adjusted here, and flows to the magnetic field 112 combined with the magnetic body 112.

Then, the magnetic flux from the other magnetic pole of the field magnet 113 flows into the teeth of the stator facing the field magnet 113 below and flows to the adjacent teeth via the stator side yoke.
That is, the magnetic flux of the field magnet 113 is the combined magnetic body 112, the magnetic body 111, the annular portion 109, the adjacent magnetic body 111, the magnetic body 112 facing the magnetic body 111, and the combined magnetic field. It flows through the magnets 113, the stator teeth, the stator side yoke, the adjacent teeth, and the united field magnet 113 facing the magnets, and flows back through the coils attached to the stator teeth.

This state is the same state as the flow of magnetic flux shown in FIG. 13 (a), thereby realizing a driving state at the time of low speed and high torque rotation.
FIG. 18 is a diagram showing the relationship of the rotational phase deviation between the first rotor 108-1 and the second rotor 108-2 at the time of high speed and low torque rotation in the configuration of the axial gap type electric motor. It is. FIG. 18 shows a state in which the rotational phase shift between the first rotor 108-1 and the second rotor 108-2 is maximized.

In this example, the first rotator 108-1 and the second rotator 108-2 can be placed at any positions from the state where the phases shown in FIG. 17 coincide with each other to the state where the phase shown in FIG. It is possible to form a gap.
When the phase shown in FIG. 18 is shifted by 15 degrees, the magnetic gap between the magnetic body 112 and the magnetic body 111 is extremely large. Therefore, the magnetic flux of the magnetic body 112 hardly flows to the magnetic body 111 and is blocked.

This state is slightly different from the state shown in FIG. 13 (b), but the gap becomes large at the portion where the magnetic flux flow has been converged and arranged until then, the magnetic flux flow is interrupted, and the teeth on the stator side are cut off. In the state where the magnetic flux does not flow through, the same state is obtained. Thereby, the drive state at the time of high speed and low torque rotation is implement | achieved.
In other words, by controlling the rotational phase shift between the first rotor 108-1 and the second rotor 108-2 at appropriate positions from the state of FIG. 17 to the state of FIG. It is possible to control the relationship between the rotational speed and the rotational torque without using unnecessary power for controlling the magnetic field by controlling the amount of magnetic flux exchange.

From the above description in this specification, the following features can be understood in addition to the features described in the claims.
1. A rotor that rotates about a rotation axis;
A stator disposed opposite the rotor;
Have
Either the rotor or the stator is divided into at least two parts, a first part including a facing part and a second part not including the facing part, and the second part moves relative to the first part. Then, the rotating electrical machine is configured to be capable of changing a gap capable of adjusting the magnetic resistance between the first part and the second part.
2. The rotating electrical machine according to claim 1, wherein the first part and the second part are divided in a direction of magnetic flux flow passing through each of the first part and the second part.
3. The rotating electrical machine according to claim 2, wherein the first part and the second part are a stator provided with a coil and are divided outside the coil.
4). The rotating electrical machine according to claim 1, 2, or 3, wherein the first part and the second part are divided in a direction in which the rotor and the stator face each other.
5). The rotating electrical machine according to claim 1 or 2, wherein the second part moves in a direction intersecting a direction of a magnetic flux flowing through the inside of the first part with respect to the first part.
6). 6. The rotating electrical machine according to claim 5, wherein the second part moves to a position out of phase in the rotation direction of the rotor with respect to the first part.
7). A rotor having two parts, an outer part and an inner part, each having an annular part that rotates around the same center of rotation and configured to be relatively movable to a position out of phase;
One end is disposed opposite to the inner part of the rotor on a surface orthogonal to the rotation axis of the rotor, winding is applied to the side peripheral surface excluding both ends, and the other end is A stator having a plurality of teeth held by a holding member;
Have
The rotation of the rotor is characterized in that a relative movement direction of the outer portion and the inner portion of the rotor is a direction perpendicular to a direction of a magnetic flux flow generated when the winding is energized and transmitted through the teeth. Electric.
8). A rotor having two parts, an outer part and an inner part, each having an annular part that rotates around the same center of rotation and configured to be relatively movable to a position out of phase;
One end is arranged opposite to the inner part of the rotor on a surface parallel to the rotation axis of the rotor, winding is applied to the side peripheral surface except both ends, and the other end is A stator having a plurality of teeth held by a holding member;
Have
The rotation of the rotor is characterized in that a relative movement direction of the outer portion and the inner portion of the rotor is a direction perpendicular to a direction of a magnetic flux flow generated when the winding is energized and transmitted through the teeth. Electric.
9. A rotor having two parts, an outer part and an inner part, each having an annular part that rotates around the same center of rotation and configured to be relatively movable to a position out of phase;
One end is arranged opposite to the outer part of the rotor on a surface parallel to the rotation axis of the rotor, winding is applied to the side peripheral surface except both ends, and the other end is A stator having a plurality of teeth held by a holding member;
Have
The rotation of the rotor is characterized in that a relative movement direction of the outer portion and the inner portion of the rotor is a direction perpendicular to a direction of a magnetic flux flow generated when the winding is energized and transmitted through the teeth. Electric.

DESCRIPTION OF SYMBOLS 1 Electric motorcycle 2 Head pipe 3 Handle 4 Handle support part 5 Grip 6 Front fork 7 Front wheel 8 Front axle 9 Meter 11 Head lamp 12 Flasher lamp 13 Car rest frame 14 Seat rail 14a Rear side end 15 Seat 16 Battery 17 Seat stay 18 Rear fender 19 Tail lamp 21 Flash lamp 22 Rear arm bracket 23 Rear arm 23a Rear end 24 Pivot shaft 25 Rear wheel 26 Rear cushion 27 Footstep 28 Side stand 29 Shaft 31 Return spring 32 Axial gap type electric motor 33 Drive unit 34 Gear cover 35 Planetary gear Reducer 36 Controller 37a, 37b Bearing BO Rotation center axis 38 Rotor 39 Stator 41 Rotor side yoke 41a Ring part 41b Tapered part 41c 1st cylindrical part 41d Annular part 41e 2nd cylindrical part 42 Field magnet (magnet)
43 Rotating shaft with teeth 44 Rear axle 44a Tip 45 Nuts 46 Stator side yoke 46a Outer peripheral surface 47 (47u, 47v, 47w) Teeth 48 Teeth missing part 49 Coil 51 Mold part 52 Flange 53 Bolt 54 Inverter 55 Encoder board 56 Wire Harness 57a, 57b, 57c Magnetic pole detection element 58 Insert hole 58a, 58b Inner side surface 59 Slit 61, 62 Magnetic flux 70 Axial gap type electric motor (electric motor)
71 Rotor 72 Rotating shaft 73 Rotor side yoke 74 Ring portion 75 Tapered portion 76 First cylinder portion 77 Ring portion 78 Second cylinder portion 79 Field magnet 80 First stator core 81 First teeth 81a 81b End surface 81c Side surface periphery 82 Winding 83 First stator 84 Second teeth 84a, 84b End portion 85 Holding member 86 Mounting hole 87 Second stator (core)
88 Stator
89 Slit 90 Gear engaging teeth 91, 92, 93 Reduction gear 94 Motor 95 Worm gear 96 Power supply 97 Controller 98a, 98b Magnetic flux flow 99a, 99b Magnetic flux flow 101, 102 Magnetic body 103 Magnetic flux 108 Rotor 108-1 First rotation Child 108-2 Second rotor 109 Annular portion of rotor yoke 111 Magnetic body 112 Magnetic body 113 Field magnet 114 Magnetic body combined magnet

Claims (11)

A rotor that includes a magnet and rotates about a rotation axis;
A stator comprising windings and disposed opposite the rotor;
Have
The stator is divided into at least two parts, a first part including a facing part facing the rotor and a second part not including the facing part;
The magnetic resistance between the first part and the second part is configured to be adjustable,
The magnetic resistance between the opposed portions of the pair of first parts adjacent to each other is made larger than the magnetic resistance between each first part and the second part, and between the N pole and S pole of the magnet. The pair of adjacent magnetic fluxes formed in the first portion is transmitted through the second portion without substantially transmitting the space between the opposing portions of the first portions adjacent to each other. A state of forming a magnetic flux flowing through the first portion;
The magnetic resistance between the opposed portions of the pair of first parts adjacent to each other is made smaller than the magnetic resistance between each first part and the second part, and between the N pole and S pole of the magnet. The magnetic flux formed in the first part is allowed to flow through the space between the opposed parts of the pair of the first parts adjacent to each other without almost flowing into the second part, and the opposed parts of the pair of the first parts and It can be changed to a state of forming a magnetic flux flow that passes through the space between the opposed portions of the pair of first portions,
The rotary electric machine is configured to be capable of adjusting a magnetic resistance between the first part and the second part by moving the second part with respect to the first part.   The rotating electrical machine according to claim 1, wherein the first part includes the winding, and the second part does not include the winding.   3. The rotating electrical machine according to claim 1, wherein the first portion has the winding between a first end surface on a side opposite to the first portion and a second end surface opposite to the facing portion.   The rotating electrical machine according to claim 3, wherein the second end face faces the second portion.   The rotating electrical machine according to any one of claims 1 to 4, wherein the first part and the second part are divided in a direction of a magnetic flux flow passing through both of the first part and the second part.   The rotating electrical machine according to claim 5, wherein the stator is divided into the first part and the second part outside the winding.   The said 2nd site | part is movable to the direction which cross | intersects the direction of the magnetic flux flow which passes both the said 1st site | part and the said 2nd site | part, It is any one of Claims 1-6 characterized by the above-mentioned. Rotating electric machine.   The rotating electrical machine according to any one of claims 1 to 7, wherein a first end surface of the first portion on a side opposite to the first portion is formed larger than a second end surface on a side opposite to the facing portion.   The rotating electrical machine according to claim 8, wherein a gap between the pair of adjacent first portions is narrow at the first end face and wide at the second end face.   10. The magnetic resistance between the first end surfaces of the pair of first portions adjacent to each other is smaller than the magnetic resistance between the second end surfaces of the pair of adjacent first portions. Rotating electric machine.   11. The magnetic resistance between the first end faces of the pair of first portions adjacent to each other is larger than the magnetic resistance between the first end face and the rotor. Rotating electric machine.