JP4369771B2 - Rotating electric machine and electric vehicle - Google Patents

Description

  The present invention relates to a rotating electrical machine capable of changing an output characteristic by changing a magnetic flux between a rotor and a stator by moving a moving member by moving a weight on a slope member along with increase / decrease in the number of rotations of a rotating shaft. The present invention relates to an electric vehicle using this rotating electric machine.

  Conventionally, as a rotating electrical machine whose characteristics are changed by centrifugal force of a weight, there are those described in Patent Documents 1 to 3 below.

  In the rotating electrical machine described in Patent Document 1, in FIG. 9, when the number of rotations of the rotating shaft 101 increases, the weight 103 is made of the soft member and the moving member 107 when the weight 103 moves up the slope 105 by centrifugal force. The auxiliary yoke 109 is moved upward. The auxiliary yoke 109 is inserted into a gap 115 provided in the yoke 113 including the permanent magnet 111, thereby reducing the magnetic resistance of the yoke 113.

  In the rotating electrical machine described in Patent Document 2, in FIG. 10, when the rotational speed of the rotating shaft 121 increases, the weight 123 moves away from the rotating shaft 121 by centrifugal force. The link 125 bends, whereby the rotor 127 moves in the direction of exiting the stator 129 and increases the magnetic resistance of the magnetic circuit composed of the rotor 127 and the stator 129.

  In the rotating electrical machine described in Patent Document 3, in FIG. 11, when the number of rotations of the rotating shaft 131 increases, the weight 133 moves outward by centrifugal force. As a result, the arm 135 supported by the shaft 135 moves the thrust plate 139 leftward. As a result, the compression spring 141 is compressed, and the rotor 143 moves in the direction of coming out of the stator 145, thereby increasing the magnetic resistance of the magnetic circuit composed of the rotor 143 and the stator 145.

Further, in these rotating electrical machines, when the rotational speed of the rotating shaft is decreased, the characteristics are reversed due to the reverse action of the above-described action.
Japanese Patent Laid-Open No. 11-122886 Japanese Utility Model Publication No. 2-146975 JP-A-64-50744

  However, in the rotating electrical machine described in Patent Document 1, since the auxiliary yoke 109 is a soft magnetic material, it is difficult to magnetize if there is a gap between the yoke 113 and, therefore, the auxiliary yoke 109 and the yoke 113 slide without gap. It is necessary to let In addition, if there is a gap, even if there is a gap, the magnetic resistance changes depending on the width of the gap, so that there is a possibility that an accurate characteristic change cannot be obtained. Therefore, high precision is required for processing the auxiliary yoke 109 and the gap 115.

  Further, in the rotating electrical machine described in Patent Document 2, the distance between the rotor 127 and the stator 129 is not determined due to the shakiness of the link 125 which is a movable part, and therefore, there is a possibility that an accurate characteristic change cannot be obtained.

  Further, in the rotating electrical machine described in Patent Document 3, the distance between the rotor 143 and the stator 145 is not determined due to the shakiness of the shaft 135 that is a movable part, and therefore, there is a possibility that an accurate characteristic change cannot be obtained.

  In addition, when a technique for obtaining a characteristic change by centrifugal force of a weight is used for a low-rotation type rotating electrical machine, for example, an electric motor that is a drive source of an electric vehicle, the weight must be made heavy in order to increase the centrifugal force. For this reason, rotating electric machines (electric motors) and electric vehicles become heavy and eventually increase in size.

  In particular, in the radial gap type rotating electrical machine described in Patent Document 1, the change in the magnetic resistance with respect to the movement amount of the auxiliary yoke 109 is small, and if this change is to be increased, the movement amount of the auxiliary yoke 109 must be increased. As a result, the rotating electric machine becomes large and difficult to use in an electric vehicle.

  The present invention has been made in view of the above problems, and the moving member moves when the weight moves on the slope member and the magnetic flux between the rotor and the stator changes as the rotational speed of the rotating shaft increases or decreases. An object of the present invention is to provide a rotating electrical machine capable of changing characteristics and an electric vehicle using the rotating electrical machine.

  Another object of the present invention is to provide a rotating electrical machine that can change the characteristics accurately by the centrifugal force of the weight, and that can be reduced in weight even if it is a low-rotation type, and an electric vehicle using this rotating electrical machine. To do.

In order to solve the above-described problems, a rotating electrical machine according to the present invention includes a rotating shaft, a rotor connected to the rotating shaft, a stator facing the rotor via an axial interval, A weight that rotates by a rotational force; a slope member that is connected to the rotary shaft, and that forms a slope in which the weight rises and falls due to an increase or decrease in centrifugal force; and is opposed to the slope in the axial direction via the weight, And a moving member that moves the rotor in the axial direction when the weight ascends and descends the slope.

According to the rotating electrical machine of the present invention , a rotating shaft, a rotor connected to the rotating shaft, a stator facing the rotor via an axial interval, a weight rotating by the rotational force of the rotor, and the rotating shaft Connected to the slope member that forms a slope where the weight rises and falls due to increase and decrease of centrifugal force, and faces the slope in the axial direction via the weight, and moves the rotor in the axial direction when the weight rises and falls on the slope Since the distance can be varied by providing the moving member, it is possible to obtain a rotating electrical machine capable of changing the output characteristics by changing the magnetic flux between the rotor and the stator.

The rotating electrical machine according to the present invention is characterized in that the slope is formed in multiple stages with different inclination angles.

According to this rotating electrical machine , since the slope is formed in multiple stages, the characteristics of the rotating electrical machine can be changed in multiple stages. Further, with respect to increase / decrease in the number of rotations, a multi-stage in which the movement of the weight stops once at the boundary between the inclined surfaces can obtain a characteristic change closer to a stepless characteristic change. In addition, the slope formed in multiple steps is easier to manufacture than a curved surface for obtaining a so-called stepless characteristic change in which the weight always changes the rotation radius with respect to increase or decrease of the rotation speed. In addition, since the characteristics can be determined by determining the boundary between the slopes, it is easy to control the rotating electrical machine.

The rotating electrical machine according to the present invention is characterized in that a mechanism for synchronously rotating the moving member and the slope member is provided outside the slope.

According to the rotating electrical machine according to the present invention, since the mechanism for synchronously rotating the moving member and the slope member is provided outside the slope, the positional deviation in the rotational direction between the members due to processing variations can be reduced. The deformation and wear of the weight sandwiched between the members can be reduced.

Further, in the rotating electrical machine according to the present invention, the distribution of the magnetic force between the stator and the rotor that generates a force in a direction that prevents the weight from going up the slope is not uniform during one rotation of the weight. It is characterized by comprising.

According to the rotating electrical machine of the present invention, the distribution of the magnetic force between the stator and the rotor that generates a force in a direction that prevents the weight from going up the slope is configured to be non-uniform during one rotation of the weight. Since the friction coefficient with the inclined surface can be reduced by applying radial vibration to the weight, the characteristics can be changed smoothly.

In the rotating electrical machine according to the present invention, the interval is constant until the rotational speed of the rotor reaches a rotational speed of 1, and the weight is inclined when the rotational speed of the rotor reaches the rotational speed of 1. The interval is changed by going up or down.

According to the rotating electrical machine of the present invention, the interval is constant until the number of rotations reaches 1, and when the number of rotations reaches 1, the step is changed by changing the interval by the weight going up or down the slope. Characteristic changes are possible.

The rotating electrical machine according to the present invention is characterized in that the weight goes up or down the slope only when the rotational speed of the rotor is 1 and within the rotational speed range including the front and rear thereof. And

According to the rotating electrical machine according to the present invention , the weight can be moved for a shorter time only when the rotation speed of the rotor is 1, so that the time during which the weight is moving can be shortened. Slope wear can be reduced.

The rotating electrical machine according to the present invention is characterized in that the rotational speed when the weight goes up the slope is larger than the rotational speed when the weight goes down the slope.

According to the rotating electrical machine of the present invention, since the rotation speed when the weight goes up the slope is larger than the rotation speed when the weight goes down the slope, it is possible to give hysteresis to the characteristic change. Also, if this rotating electrical machine is used for an electric motor that drives an electric vehicle, the weight does not move due to a slight change in the number of rotations, and a shift contrary to the will of the occupant can be prevented, thereby realizing a smooth running. .

  According to the present invention, the rotating shaft, the rotor connected to the rotating shaft, the stator facing the rotor with an axial interval therebetween, the weight rotating by the rotational force of the rotor, and the rotating shaft are connected, A slope member that forms a slope in which the weight rises and falls due to increase and decrease of centrifugal force, and a moving member that faces the slope in the axial direction via the weight and moves the rotor in the axial direction when the weight rises and falls on the slope. Since the interval can be varied, a rotating electrical machine capable of changing the output characteristics by changing the magnetic flux between the rotor and the stator can be obtained.

  In addition, since the moving member for moving the rotor and the rotor are integrally configured, there is no sliding part or movable part in this structure, and thus there is no rattling, so the characteristics can be changed with high accuracy. Furthermore, since the stator and the stator are arranged so as not to overlap each other in the axial direction, the rotation radius can be increased without being disturbed by the stator. Since a force can be obtained, the weight can be reduced even if the rotating electrical machine is of a low rotation type. In particular, in the case of an axial gap type rotating electrical machine, the diameter of the stator is large, that is, the rotational radius of the weight can be increased, so that the weight can be made lighter. Therefore, in the case of an axial gap type rotating electrical machine, a higher effect can be obtained.

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

  FIG. 1 is a side view of an electric motorcycle to which an electric motor according to the present invention is applied.

  The electric motorcycle 1 shown in FIG. 1 includes a head pipe 2 at an upper front portion of the vehicle body, and a steering shaft (not shown) is rotatably inserted into the head pipe 2. A handle 3 is attached to the upper end of the steering shaft. Grips 4 are attached to both ends of the handle 3, and the grip 4 on the right side (the back side in FIG. 1) (not shown) constitutes a rotatable throttle grip.

  An upper part of a pair of left and right front forks 5 is attached to the lower part of the head pipe 2, and a front wheel 6 is rotatably supported by a front axle 7 at the lower end of each front fork 5. A meter 8 is disposed at the center of the handle 3, a headlamp 9 is disposed below the meter 8, and flasher lamps 10 (only one is shown in FIG. 1) are provided on both sides thereof. It has been.

  From the head pipe 2, a pair of left and right body frames 11 are extended toward the rear of the body. The vehicle body frame 11 has a round pipe shape, extends obliquely downward from the head pipe 2 toward the rear of the vehicle body, and then bends in an arc shape toward the rear to extend substantially horizontally behind the vehicle body. A pair of left and right body frames 12 extend obliquely upward from the rear end portion of each body frame 11 and are connected to each other behind the seat 13. A battery 14 is disposed between the pair of left and right body frames 12.

  A seat stay (not shown) having an inverted U shape is connected to the left and right body frames 12 and supported by a pair of left and right stays 15 (only one is shown). The seat 13 is disposed on the seat stay so as to be openable and closable.

  A tail lamp 17 is attached to the rear surface of the rear fender 16 attached to the rear end of the vehicle body frame 12, and flasher lamps 18 (only one is shown) are arranged on the left and right sides thereof.

  On the other hand, a pair of left and right rear arm brackets 19 (only one is shown) are welded to the rear ends of the left and right body frames 11, and the front end of the rear arm 20 swings up and down on the pivot shaft 21 on the rear arm bracket 19. It is supported freely. A rear wheel 22 as a drive wheel is rotatably supported at the rear end of the rear arm 20, and the rear arm 20 and the rear wheel 22 are suspended from the vehicle body frame 12 by a rear cushion 23.

  Also, foot steps 24 (only one is shown) are respectively attached below the left and right body frames 11, and a side stand 25 is rotatably supported by a shaft 26 at the lower portion of the rear arm 20. The side stand 25 is biased to the closing side by a return spring 27.

  A thin axial gap type electric motor 28 that is flat in the vehicle width direction is accommodated in a substantially circular portion at the rear end of the rear arm 20.

  FIG. 2 is a cross-sectional view taken along line AA in FIG. 3 is a cross-sectional view of the electric motor 28 in the direction of the arrow BB in FIG.

  A cover 20b is attached to the case 20a, which is a housing at the rear end of the rear arm 20. Bearings 20c and 20d are provided inside the central portion of the case 20a, and bearings 20e and 20e are provided inside the central portion of the cover 20b. A rear axle 20f is rotatably supported on the bearings 20e and 20e. A wheel 22a is inserted through the rear axle 20f, and is rotatably supported by the nut 20g from the outside together with the rear axle 20f. A tire 22b is attached to the outer periphery of the wheel 22a.

  A stator 29 constituting the electric motor 28 is fixed to the case 20a. The stator 29 includes an annular stator yoke 29a fixed to the case 20a, a plurality of teeth 29b inserted and fixed in a plurality of fitting holes formed in a substantially circular shape in the stator yoke 29a, and a bobbin ( Insulator) 29c is wound with a coil 29d and molded with resin or the like.

  As shown in FIG. 3, the stator 29 is formed by arranging a plurality of teeth 29 b on an arc of a circle excluding a part, and an encoder formed by resin integrally with the stator 29 in the removed part. The board attaching portions 29e and 29e extend. An encoder substrate 30 for detecting the rotation state of the rotor is placed on the encoder substrate attachment portions 29e and 29e, and is fixed by bolts.

  An inverter 31 electrically connected to the stator 29 is fixed to the case 20a via an elastic material (not shown).

  Returning to FIG. 2, a lower end portion of a rotor shaft 33 (also referred to as a rotation shaft) 33 formed in a columnar shape is supported on the bearing 20 c so as to be rotatable and immovable in the axial direction. Above the lower end portion of the rotor shaft 33, a convex portion extending in the axial direction is formed over the entire periphery, and the bearing 20d is fitted to the lower portion of the convex portion.

  Above the bearing 20d, a support member 35 having a cylindrical shape and a flange at the top is provided. The support member 35 is fitted in the outer peripheral portion of the rotor shaft 33 by forming a groove that fits in the convex portion of the rotor shaft 33 in the inner peripheral portion thereof.

  Above the support member 35, an annular slope member 37 having a concave portion fitted to the convex portion of the rotor shaft 33 on the inner peripheral portion is fitted to the outer peripheral portion of the rotor shaft 33, and a screw is attached to the flange of the support member 35. It has been stopped.

  4A is a plan view of the slope member 37 in the direction of the arrow CC in FIG. 2, and FIG. 4B is a sectional view taken along the line DD in FIG.

  The slope member 37 is integrally formed from a single plate by drawing or cutting. An annular base portion 37a perpendicular to the central axis (also simply referred to as an axis) of the rotor shaft 33 is formed at the center of the slope member 37, and a concave portion that fits into the convex portion of the rotor shaft 33 is formed on the inner peripheral portion thereof. Is formed. The base portion 37 a is provided with a screw hole used for screwing with the flange of the support member 35.

  Around the base portion 37a, an annular first slope portion 37b is formed that is inclined at an inclination angle θ1 (> 0) with respect to the base portion 37a perpendicular to the axis. An annular second inclined surface portion 37c is formed around the first inclined surface portion 37b and is inclined at an inclination angle θ2 (> θ1) with respect to the base portion 37a. A cylindrical portion 37d parallel to the axis is formed around the second inclined surface portion 37c.

  The base portion 37a extends to the outside of the cylindrical portion 37d at three portions that are equal in the circumferential direction, and a U-shaped portion 37e that opens outward is formed at the tip.

  Returning to FIG. 2, above the slope member 37, a cylindrical cylindrical member 39 that fits the convex portion of the rotor shaft 33 is fitted to the outer peripheral portion of the rotor shaft 33.

  At the lower end portion of the cylindrical member 39, a cylindrical cylindrical member 41 that is fitted to the outer peripheral portion of the cylindrical member 39 is fitted to the outer peripheral portion of the cylindrical member 39.

  In the base portion 37 a of the slope member 37, columnar weights 43 are arranged at 12 locations that are even in the circumferential direction, and the weight 43 is in contact with the outer peripheral portion of the cylindrical member 41. Further, the weight 43 is in contact with the base portion 37a.

  Above the weight 43, an annular moving member 45 penetrates the cylindrical member 39 and faces the slope member 37 via the weight 43 in the axial direction. The moving member 45 is locked to the slope member 37 at the outer peripheral portion thereof.

  FIG. 5A is a plan view of the moving member 45 in the direction of the EE arrow in FIG. 2, and FIG. 5B is a cross-sectional view along the FF arrow in FIG. 6A is a cross-sectional view taken along the line GG in FIG. 5A, and FIG. 6B is a cross-sectional view taken along the line HH in FIG.

  A through hole 45 a having a diameter slightly larger than the outer diameter of the cylindrical member 39 is formed at the center of the moving member 45. An annular portion 45b perpendicular to the axis is formed around the through hole 45a, and the annular portion 45b is provided with a screw hole used for screwing with the moving member 51 described later.

  The annular portion 45b is provided with a guide wall 45c that prevents the twelve weights 43 from moving in the rotation direction and guides the weights 43 in the radial direction perpendicular to the axial direction. A guide path 45d sandwiched between two guide walls 45c is formed.

  Further, the annular portion 45b further extends in the radial direction at three equal positions in the circumferential direction, and a column 45e locked to the U-shaped portion 37e of the slope member 37 is pivoted at the tip thereof. Standing in the direction.

  Fig.7 (a) is a top view of the shock absorbing material 47 pinched | interposed between the U-shaped part 37e and the pillar 45e, FIG.7 (b) is the side view.

  Since the slope member 37 and the moving member 45 are manufactured separately, it is difficult to eliminate a gap in the rotational direction between the U-shaped portion 37e and the column 45e. If there is a gap in the rotational direction, the slope member 37 and the moving member 45 cannot be rotationally synchronized accurately.

  On the other hand, the cushioning material 47 is made of plastic, the groove 47a of the cushioning material 47 is sandwiched in the rotational direction by the U-shaped portion 37e, and the column 45e is sandwiched in the rotational direction by the concave portion 47b of the cushioning material 47. The member 37 and the moving member 45 can be rotated in synchronization with each other accurately, and positional deviation and vibration in the rotation direction can be prevented.

  Returning to FIG. 2, an oil-impregnated bearing 49 is press-fitted into the moving member 51 above the moving member 45, and the oil-impregnated bearing 49 and the cylindrical member 39 are slidably inserted in the axial direction. The moving member 45 and the moving member 51 are integrally configured by screwing the flange below the moving member 51 to the moving member 45.

  Above the moving member 51, a rotor 53 that constitutes the electric motor 28 and rotates together with the rotor shaft 33 is provided. In the rotor 53, an annular rotor yoke 53 a having a concave portion that fits in the convex portion of the rotor shaft 33 is fitted in the outer peripheral portion of the rotor shaft 33. The rotor yoke 53a and the moving member 51 are integrally configured by screwing the rotor yoke 53a to the flange portion on the moving member 51.

  The rotor yoke 53a has a plurality of magnetic poles and a ring-shaped magnet 53b formed so that the polarities thereof are alternately fixed to the outer periphery of the lower surface of the rotor yoke 53a. The magnet 53b is opposed to the teeth 29b of the stator 29 via an axial gap (interval) G.

  Above the rotor yoke 53a, a planetary gear reducer 55 is provided around the rotor shaft 33 to reduce the rotational speed of the rotor shaft 33 and transmit the driving force to the rear axle 20f.

  The planetary gear reducer 55 rotates and revolves by meshing with a housing 55a housed in the cover 20b, a ring gear 55b provided inside the housing 55a, a convex portion of the outer peripheral portion of the rotor shaft 33, and the ring gear 55b. The planetary gear 55c and a support plate 55d that supports the planetary gear 55c are configured, and the support plate 55d is integrated with the lower portion of the rear axle 20f.

  Above the planetary gear reducer 55, the upper end portion of the rotor shaft 33 is rotatably supported by the bearing 20h below the rear axle 20f and immovably in the axial direction.

  Next, the operation of the present embodiment will be described.

  FIG. 8 is a diagram showing the relationship between the rotational speed of the electric motor 28 and the position of the weight.

  When the electric motorcycle 1 is started, the inverter 31 applies the electric power of the battery 14 to the stator 29, and a current flows through the coil 29d. Then, the teeth 29b generate an attractive force and a repulsive force with respect to the magnet 53b, whereby the rotor yoke 53a starts to rotate.

  When the rotor yoke 53a rotates, the rotor shaft 33 rotates accordingly, and the planetary gear speed reducer 55 decelerates the rotational speed, whereby the rear axle 20f rotates at the rotational speed after deceleration. When the rear axle 20f rotates, the wheel 22a and the tire 22b rotate, and the electric motorcycle 1 starts running.

  Further, when the rotor shaft 33 rotates, the support member 35, the slope member 37, the cylindrical member 39, and the cylindrical member 41 rotate. Moreover, the moving member 51 and the moving member 45 rotate with rotation of the rotor yoke 53a. When the moving member 45 rotates, the guide wall applies a rotational force to the weight 43, and thereby the weight 43 rotates about its axis.

  Here, the slope member 37 is supported by the convex portion of the rotor shaft 33 on its inner peripheral side and rotates, and the moving member 45 is similarly connected to the convex portion of the rotor shaft 33 via the movable member 51 and the rotor yoke 53a. Rotate supported. Therefore, if there is rattling between the convex portion on the inner peripheral side and the portion fitted to the convex portion, a positional deviation in the rotational direction occurs between the slope member 37 and the moving member 45. Moreover, the deviation increases as the distance from the axis increases. Therefore, the positional deviation at the base part 37a where the weight 43 is initially located and the first slope part 37b and the second slope part 37c where the weight 43 rises and descends is larger than the positional deviation near the axis.

  However, since the convex portion of the rotor shaft 33 that is a mechanism for synchronizing the rotation of the slope member 37 and the moving member 45 is formed on the outer peripheral portion of the rotor shaft 33 with a short distance from the shaft, its dimensional tolerance is extremely reduced. Therefore, it is not possible to reduce misalignment at the base 37a, the first slope 37b, or the second slope 37c.

  In the present embodiment, the U-shaped portion 37e, the column 45e, and the buffer material 47 that synchronize the moving member 45 and the slope member 37 outside the slope are provided. Can be reduced. As a result, deformation, wear, and load of the weight 43 sandwiched between the slope member 37 and the moving member 45 can be reduced, so that the accuracy of shifting can be improved and deterioration with time can be reduced. In addition, since the moving member 45 is locked to the slope member 37 on the outer peripheral side of the slope, it is not necessary to process the convex portion and the concave portion fitted to the convex portion, so that the manufacturing cost can be reduced. Become.

  Now, when the weight 43 rotates, the weight 43 tries to run from the base portion 37a of the slope member 37 to the first slope portion 37b by centrifugal force, but an attractive force acts between the teeth 29b and the magnet 53b, so that the rotor yoke 53a, the moving member 51, and the moving member 45 are urged downward, and the frictional force with the slope member 37 acts on the weight 43, so that the centrifugal force reaches the number of rotations that exceeds the frictional force and the suction force. Until then, the weight 43 remains on the outer peripheral portion of the base portion 37a, and the gap G is also kept constant. The electric motor 28 at this time is in the first speed state and has the characteristics of low rotation / high torque.

  Here, when the rotation speed increases and exceeds the first rotation speed and reaches the second rotation speed, the balance of force is lost, whereby the weight 43 rides on the first inclined surface portion 37b. And once it gets on the 1st slope part 37b, the weight 43 moves the moving member 45, the moving member 51, and the rotor yoke 53a upward, and, thereby, the gap G becomes wide. Since the suction force is inversely proportional to the square of the gap G, once the gap G becomes wider, the suction force decreases rapidly. Thereby, the weight 43 reaches | attains at a stretch to the boundary of the 1st slope part 37b and the 2nd slope part 37c. That is, the electric motor 28 is shifted to the high rotation side by one step and is in the second speed state. Since the force is balanced even if the rotational speed is further increased, the weight 43 remains at this boundary, and the gap G is also kept constant. The electric motor 28 at this time has the characteristics of medium rotation / medium torque.

  Thus, in the present embodiment, when the rotational speed reaches the second rotational speed (or the third and first rotational speeds described later), the weight 43 goes up the slope or descends as described later. Since the interval is changed by, a stepwise characteristic change becomes possible.

  Further, in a configuration where the rotational speed is within the rotational speed range including the second rotational speed (or third and first rotational speeds described later) and the front and rear thereof, the weight goes up or down only when the rotational speed is concerned. As a result, the time during which the weight 43 is moving can be shortened, and wear of the weight 43 and the slope can be reduced.

  Further, the moving member 45 is opposed to the slope in the axial direction with the weight 43 interposed therebetween, and moves the rotor 53 in the axial direction when the weight 43 goes up the slope or goes down the slope as described later. However, since the moving member 45 is configured integrally with the rotor 53 together with the moving member 51, there is no sliding portion or movable portion in such an integrated configuration, and rattling or the like is eliminated. The characteristics of the electric motor 28 can be changed with high accuracy.

  Further, by disposing the moving member 45 below the stator 29 in the axial direction, the weight 43 and the stator 29 are disposed so as not to overlap each other in the axial direction. Since it is possible to obtain a high centrifugal force and thereby change the characteristics of the motor, the weight can be reduced even if the electric motor is of a low rotation type. Moreover, the freedom degree of design improves by arrange | positioning the weight 43 and the stator 29 so that it may not overlap.

  By the way, when the axial gap type and the radial gap type are compared, the outer diameter of the stator is larger in the axial gap type in the same output electric motor. Moreover, the case of a rotary electric machine is made in the magnitude | size according to the stator which is the largest components. Therefore, if the weight and the stator are arranged so as not to overlap each other in the axial direction, the weight can be lightened by increasing the rotation radius of the weight while the weight is accommodated in the case. A higher effect can be obtained.

  Further, the stator is a heavy component among the electric motors, and since this stator is disposed between the rotor and the weight, the weight balance of the rotating electric machine can be suitably achieved with the heavy stator at the center. In particular, in an electric motorcycle, the left and right balance is maintained, and the straight running stability can be improved. Also, it is difficult for a difference between the feel when turning to the right and the feel when turning to the left. As a result, a comprehensively balanced electric motorcycle can be provided.

  Now, when the number of rotations further increases and reaches the third number of rotations, the balance of force is lost, and thereby the weight 43 rides on the second inclined surface portion 37c. And once it gets on the 2nd slope part 37c, the weight 43 moves the moving member 45, the moving member 51, and the rotor yoke 53a upward, and, thereby, the gap G becomes wide. Also, the suction force decreases rapidly. Thereby, the weight reaches the cylindrical part 37d at a stretch. That is, the electric motor 28 further shifts by one step toward the high rotation side and enters the third speed state. Since the force is balanced even if the number of rotations further increases, the weight 43 remains at this position, and the gap G is also kept constant. The electric motor at this time has characteristics of high rotation / low torque.

  On the contrary, when the rotational speed is decreased and the rotational speed is decreased to the fourth rotational speed, the balance of force is lost, whereby the weight 43 starts to descend the second inclined surface portion 37c. Once the second slope 37c starts to descend, the rotor yoke 53a moves downward, thereby narrowing the gap G. Since the suction force increases rapidly, the weight 43 reaches the boundary between the first slope portion 37b and the second slope portion 37c at a stretch. That is, the electric motor 28 is decelerated to the second speed. Since the force is balanced even if the number of rotations further decreases, the weight 43 remains at this position, and the gap G is also kept constant.

  Further, when the rotational speed falls to the fifth rotational speed, the balance of force is lost, whereby the weight 43 starts to descend the first slope portion 37b. Once the first slope portion 37b starts to descend, the rotor yoke 53a moves downward, thereby narrowing the gap G. Since the suction force increases rapidly, the weight 43 reaches the base 37a at a stroke. That is, the electric motor 28 is decelerated to the first speed. Since the force is balanced even if the number of rotations further decreases, the weight 43 remains on the base portion 37a, and the gap G is also kept constant.

  Here, when comparing the rotation speed when going up the slope and the rotation speed when going down the slope, the former is larger than the latter. This is because the gap G becomes wider and the suction force decreases after climbing the slope. Therefore, for example, even if the number of revolutions changes slightly, the weight does not go down the slope unless the number of revolutions is reduced to the number of revolutions when going up one slope below. That is, in the present embodiment, it is possible to give hysteresis to the characteristic change. As a result, it is possible to obtain a good speed change characteristic that can prevent a speed change contrary to the occupant's will, thereby enabling smooth running.

  For example, in an electric two-wheeled vehicle, the opening degree always changes minutely even if it is intended to travel with the accelerator opening kept constant. As a result, the rotation speed of the electric motor always changes, and the gap G also changes constantly. Therefore, if there is no hysteresis in the speed change characteristic, smooth running cannot be performed. However, in this embodiment, since the speed change characteristic is provided with hysteresis, such inconvenience can be prevented and smooth running can be realized.

  Further, in an electric motorcycle, the rotor is rotated by the rear axle on a downhill or the like, and a reverse current flows through the inverter by the counter electromotive force generated thereby. Therefore, as a mechanism for preventing the inverter from being damaged by this current, it is necessary to equip a one-way clutch that mechanically cuts off the force applied to the electric motor from the rear axle.

  On the other hand, in the present embodiment, even if the rotor is over-rotated by the rear axle, the gap G can be widened rapidly. A special mechanism such as a clutch is not required.

  Moreover, since the gap G once widened does not become narrow unless it is reduced to a safe rotational speed for the inverter by utilizing the hysteresis of the transmission ratio, it is possible to prevent the generation of a back electromotive voltage until the rotational speed is reached. Thereby, the inverter can be reliably protected.

  Moreover, it is preferable to apply such a configuration to the generator because it is possible to prevent generation of a high voltage due to over-rotation, and a rotating electric machine having the functions of the electric motor and the generator at the same time is used as an electric motorcycle. If this is used, it is possible to save space, which is more preferable.

  By the way, when constructing an electric motor that can change without steps, a curved surface whose inclination angle continuously increases from the inner peripheral side to the outer peripheral portion is used instead of the inclined surface so that the weight does not move on the inclined surface at once. Must be formed.

  However, the curved surface is not easy to manufacture compared to the inclined surface, which makes it difficult to reduce the manufacturing cost. In addition, when the curved surface is used, the motor characteristics are always changed as compared with the case where the inclined surface is used, so that it is difficult to control the electric motor. When a curved surface is used, the weight always moves on the curved surface while the rotation speed is changing, so that the curved surface and the weight are heavily worn.

  In particular, in the case of the axial gap type as in the present embodiment, the suction force is larger than that in the radial gap type, and the degree of reduction in the suction force when the gap becomes large is the same as that in the case of the radial gap type. Bigger than. That is, the suction force decreases more rapidly than in the radial gap type. Moreover, since the characteristic change with respect to the change of the gap is larger than that in the case of the radial gap type, the gap must be controlled more precisely than in the case of the radial gap type, but such control requires difficulty.

  For these various reasons, it has been impossible to realize an axial gap type electric motor that can be shifted by the centrifugal force of the weight.

  On the other hand, in this embodiment, since a simple slope is used instead of a curved surface, the shape is simple and easy to manufacture, whereby an electric motor can be manufactured at low cost. Further, since the speed change characteristic is determined only by the position where the tilt angle changes, that is, the position of the boundary between the slopes, the electric motor can be easily designed and controlled, and the degree of freedom in design is increased.

  In addition, since the slopes are combined, the force opposite to the centrifugal force becomes strong at the boundary, thereby making it possible to easily stop the weight. This eliminates the need for a spring that prevents the gap from expanding rapidly.

  In the present embodiment, the electric motor can be shifted in three stages, and if the slope is further increased, four or more stages can be shifted.

  In other words, in the present embodiment, by making the slope multi-stage, it is possible to obtain an output characteristic close to that of an electric motor that can change gears without any step, with a simple configuration at low cost and with simple control.

  By the way, as shown in FIG. 3, the stator 29 has a plurality of teeth 29b arranged on an arc of a circle excluding a part thereof, that is, the teeth 29b (and the coil 29d) are formed in a part of the arc. It is excluded. That is, the distribution of the magnetic force between the stator 29 and the rotor 53 that generates a force that prevents the weight 43 from going up the slope is non-uniform, and no attractive force is generated in a portion where no magnetic force is generated. Therefore, the rotor yoke 53a is inclined upward at that portion, and the moving member 45 connected to the rotor yoke 53a via the moving member 51 is also inclined.

  On the other hand, the rotor shaft 33 receives a force due to the inclination of the rotor yoke 53a, but is supported by the bearing 20h and the bearing 20c in the vertical direction, so that the rotor shaft 33 itself does not tilt. Therefore, the slope member 37 connected to the rotor shaft 33 is not similarly inclined.

  For this reason, when the weight 43 is rotationally moved to a place without the teeth 29b, the moving member 45 is slightly inclined upward, and when the weight 43 is rotationally moved from there to a place with the teeth 29b, the moving member 45 is slightly inclined downward. Then, the weight 43 sandwiched between the moving member 45 that vibrates up and down and the slope member 37 that is not inclined with respect to the rotor shaft 33 slightly vibrates in the rotational radius direction at the same frequency as that of the rotor yoke 53a.

  Here, the frictional force that opposes the centrifugal force when the weight 43 rides on the first slope portion 37b or the second slope portion 37c is determined by the dynamic friction coefficient because the weight 43 slightly vibrates. On the other hand, for example, if the distribution of magnetic force between the stator 29 and the rotor 53 is uniform, fine vibration does not occur, and the frictional force is determined by a static friction coefficient larger than the dynamic friction coefficient. That is, the frictional force in the present embodiment is smaller than that in the case where the magnetic force distribution between the stator 29 and the rotor 53 is uniform, so that the weight 43 can be lightened. Further, even when an access operation is suddenly performed, the weight of the rotating object can be reduced, so that a quick shift can be performed. That is, it is possible to improve the follow-up performance of the shift operation with respect to the access operation.

  In this embodiment, the tooth (and coil) is excluded from a part of the arc, but the number of turns of the coil, the current value of the coil, the phase of the coil current, the direction of the magnetic force from the tooth, etc. It may be uniform. Moreover, it is good also as a structure which removed a part of magnet. Further, the magnetization of the magnetic pole, the direction of the magnetic force from the magnetic pole, etc. may be made non-uniform.

  In the present embodiment, the mechanism for synchronously rotating the moving member 45 and the slope member 37 is provided at three locations, but it is not necessary to limit the number and position. Further, a slope may be formed on the moving member 45.

  Further, in the present embodiment, the fourth rotational speed is made larger than the second rotational speed, but the fourth rotational speed may be made equal to or lower than the second rotational speed.

  The present invention can be applied not only to the electric motorcycle as in the present embodiment but also to an electric vehicle having three or more wheels. Further, the drive wheel may not be a rear wheel.

1 is a side view of an electric motorcycle according to an embodiment of the present invention. It is AA arrow sectional drawing of FIG. It is sectional drawing of the electric motor 28 in the direction of the BB line arrow of FIG. 4A is a plan view of the slope member 37 in the direction of the arrow CC in FIG. 2, and FIG. 4B is a sectional view taken along the line DD in FIG. FIG. 5A is a plan view of the moving member 45 in the direction of the EE arrow in FIG. 2, and FIG. 5B is a cross-sectional view along the FF arrow in FIG. 6A is a cross-sectional view taken along the line GG in FIG. 5A, and FIG. 6B is a cross-sectional view taken along the line HH in FIG. Fig.7 (a) is a top view of the shock absorbing material 47, FIG.7 (b) is the side view. It is a figure which shows the relationship between the rotation speed of the electric motor 28, and the position of a weight. It is a figure which shows one structure of the conventional rotary electric machine. It is a figure which shows another structure of the conventional rotary electric machine. It is a figure which shows another one structure of the conventional rotary electric machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electric motorcycle 20 ... Rear arm 20a ... Case 20b ... Cover 20c, 20d, 20e, 20h ... Bearing 20f ... Rear axle 22 ... Rear wheel 22a ... Wheel 22b ... Tire 28 ... Electric motor 29 ... Stator 29a ... Stator yoke 29b ... Teeth 29d ... Coil 31 ... Inverter 33 ... Rotor shaft (rotary shaft)
35 ... support member 37 ... slope member 37a ... base part 37b ... first slope part 37c ... second slope part 37d ... cylindrical part 37e ... U-shaped part 39, 41 ... cylindrical member 43 ... weight 45, 51 ... movement Member 45a ... Through hole 45b ... Ring portion 45c ... Guide wall 45d ... Guide path 45e ... Pillar 47 ... Buffer material 49 ... Oil-impregnated bearing 53 ... Rotor 53a ... Rotor yoke 53b ... Magnet 55 ... Planet gear reducer

Claims (6)

A rotation axis;
A rotor connected to the rotating shaft;
A stator facing the rotor via an axial interval;
A weight rotating by the rotational force of the rotor;
A slope member that is connected to the rotation shaft and forms a slope in which the weight rises and falls due to increase and decrease of centrifugal force;
A moving member that is opposed to the slope in the axial direction via the weight and moves the rotor in the axial direction when the weight ascends and descends the slope ; and
The inclined surface is a rotating electrical machine formed in multiple stages with different inclination angles . A rotation axis;
A rotor connected to the rotating shaft;
A stator facing the rotor via an axial interval;
A weight rotating by the rotational force of the rotor;
A slope member that is connected to the rotation shaft and forms a slope in which the weight rises and falls due to increase and decrease of centrifugal force;
A moving member that is opposed to the slope in the axial direction via the weight and moves the rotor in the axial direction when the weight ascends and descends the slope;
With
A rotating electrical machine having a mechanism for rotating the moving member and the slope member synchronously outside the slope . A rotation axis;
A rotor connected to the rotating shaft;
A stator facing the rotor via an axial interval;
A weight rotating by the rotational force of the rotor;
A slope member that is connected to the rotation shaft and forms a slope in which the weight rises and falls due to increase and decrease of centrifugal force;
A moving member that is opposed to the slope in the axial direction via the weight and moves the rotor in the axial direction when the weight ascends and descends the slope;
With
A rotating electrical machine configured such that a distribution of magnetic force between the stator and the rotor, which generates a force in a direction that prevents the weight from going up the slope, is non-uniform during one rotation of the weight . A rotation axis;
A rotor connected to the rotating shaft;
A stator facing the rotor via an axial interval;
A weight rotating by the rotational force of the rotor;
A slope member that is connected to the rotation shaft and forms a slope in which the weight rises and falls due to increase and decrease of centrifugal force;
A moving member that is opposed to the slope in the axial direction via the weight and moves the rotor in the axial direction when the weight ascends and descends the slope;
With
The interval is constant until the number of rotations of the rotor reaches the number of rotations of 1. When the number of rotations of the rotor reaches the number of rotations of 1, the intervals change as the weight goes up or down the slope. rotating electric machine. A rotation axis;
A rotor connected to the rotating shaft;
A stator facing the rotor via an axial interval;
A weight rotating by the rotational force of the rotor;
A slope member that is connected to the rotation shaft and forms a slope in which the weight rises and falls due to increase and decrease of centrifugal force;
A moving member that is opposed to the slope in the axial direction via the weight and moves the rotor in the axial direction when the weight ascends and descends the slope;
With
A rotating electrical machine in which the weight moves up or down the slope only when the rotation speed of the rotor is 1 and within the rotation speed range including the front and rear thereof . A rotation axis;
A rotor connected to the rotating shaft;
A stator facing the rotor via an axial interval;
A weight rotating by the rotational force of the rotor;
A slope member that is connected to the rotation shaft and forms a slope in which the weight rises and falls due to increase and decrease of centrifugal force;
A moving member that is opposed to the slope in the axial direction via the weight and moves the rotor in the axial direction when the weight ascends and descends the slope;
With
A rotating electrical machine in which the rotational speed when the weight goes up the slope is larger than the rotational speed when the weight goes down the slope .

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