JP4800091B2 - Electric motor - Google Patents

Description

  The present invention relates to an electric motor that includes a permanent magnet in a rotor and can change the field characteristics of the permanent magnet.

  Conventionally, an outer peripheral rotor including a permanent magnet and an inner peripheral rotor including a permanent magnet are concentrically arranged, and either the outer peripheral rotor or the inner peripheral rotor is arranged around the other. There is known an electric motor that changes the relative phase between an outer circumferential rotor and an inner circumferential rotor by rotating in a direction (see, for example, Patent Document 1).

  In this electric motor, when the relative phase of both rotors is changed according to the rotational speed of the electric motor, the outer rotor and the inner rotor are rotated by a member that is displaced along the radial direction by the action of centrifugal force. Either one of the children is rotated in the circumferential direction with respect to the other. In addition, when the relative phase of both rotors is changed according to the speed of the rotating magnetic field generated in the stator, a control current is applied to the stator winding in a state where each rotor maintains the rotation speed due to inertia. The relative position in the circumferential direction of the outer peripheral side rotor and the inner peripheral side rotor is changed by energizing and changing the rotating magnetic field speed.

And the characteristic (ratio of induced voltage / rotation speed) of an electric motor can be made variable by changing the relative phase of an outer peripheral side rotor and an inner peripheral side rotor. Specifically, when the permanent magnet of the outer rotor and the permanent magnet of the inner rotor face each other with different polarities (same polarity arrangement), the field is in a stronger state (stronger field phase). Thus, the induced voltage becomes large. On the other hand, when the permanent magnet of the outer rotor and the permanent magnet of the inner rotor face each other with the same polarity (counter electrode arrangement), the field becomes weakened (weak field phase). The induced voltage becomes small.
JP 2002-204541 A

  By the way, this type of electric motor is mounted as a drive source in, for example, a hybrid vehicle or an electric vehicle. The electric motor mounted on the vehicle not only drives the vehicle but also functions as a generator that generates a regenerative braking force, and collects the kinetic energy of the vehicle body as electric energy (regenerative energy).

  However, when this type of electric motor is used as a drive source in a hybrid vehicle, an electric vehicle, etc., the driving force increases or decreases and the speed changes rapidly due to changes in driving operation conditions and road surface conditions during vehicle travel. To do. At this time, if the phase between the outer peripheral rotor and the inner peripheral rotor of the electric motor is changed to a desired phase, one of the rotating rotors may increase or decrease the driving force of the vehicle or increase the rapid speed. Due to the influence of the change, it is rapidly rotated, and it becomes difficult to change the phase to a desired phase by excessive rotation due to the accompanying rotation inertia or the like. Further, when a restricting member is provided that restricts one rotating rotor within a predetermined phase range, the rotor strongly hits the restricting member due to a rotation inertia caused by a sudden turning, and the impact is applied. May occur.

  In addition, when this type of electric motor is used as a generator in a hybrid vehicle, the torque of the internal combustion engine, which is another driving source, fluctuates due to a change in driving operation status, and the vibration caused by this torque fluctuation and the phase between both rotors In addition, the vibration is amplified by the resonance with the natural frequency due to the rotational inertia of the two rotors, and the phase displacement between the two rotors becomes unstable.

  The present invention has been made in view of the above circumstances, and provides an electric motor that can prevent abrupt displacement of the phase between both rotors and can stabilize the phase displacement between both rotors. With the goal.

In order to achieve such an object, the present invention includes a pair of rotors in which a plurality of permanent magnets having different polarities are alternately arranged along the circumferential direction, and are provided concentrically around the rotating shaft, and the rotating shaft rotates. An electric motor in which the relative phase between the two rotors is changed by rotating one rotor with respect to the other rotor according to the speed, and one rotor is relative to the other rotor. Bei give a frictional resistance applying means for applying a frictional resistance between the two rotors during the rotation Te, the frictional resistance applying means includes a friction disk disposed on one of the rotor, provided on the other rotor and pressure plates, characterized Rukoto a pressing means for applying a frictional resistance between the two rotors by pressing the pressure plate to the friction disc.

  According to the present invention, since the frictional resistance is imparted between the two rotors by the frictional resistance imparting means, inadvertent rotation of the rotor is prevented, and a sudden phase shift between the two rotors is prevented. can do. As a result, when the electric motor of the present invention is used as a drive source in a hybrid vehicle, an electric vehicle, or the like, a driving force increase / decrease or a rapid speed change occurs due to a change in a driving operation situation or a road surface condition when the vehicle travels. However, the phase between the two rotors can be reliably changed to a desired phase. In addition, even when a restricting member that restricts one of the rotating rotors within a predetermined phase range is provided, the rotor can be prevented from rotating suddenly, so that the rotor collides with the restricting member. Can be prevented, and the occurrence of impact can be suppressed.

  Furthermore, when the electric motor is used as a generator in a hybrid vehicle, even if torque fluctuation occurs in the internal combustion engine as another driving source, friction resistance is applied between the rotors by the friction resistance applying means. The vibration energy between the rotors can be attenuated by the frictional resistance, and the phase displacement between the two rotors can be stabilized.

In the present invention, the press contact means is characterized in that the press contact plate is pressed against the friction disk at a position where both the rotors are in a predetermined phase, and a frictional resistance is applied between the both rotors.

  According to the present invention, the pressure contact means presses the pressure contact plate against the friction disk to provide a frictional resistance between the two rotors. Therefore, when the phase between the two rotors is suddenly changed or between the two rotors. Only when it is necessary to stabilize the phase displacement, the pressure contact means can be operated to provide a frictional resistance between the two rotors. Also, if the pressure contact plate is operated and the pressure contact plate is firmly pressed against the friction disk, the two rotors can be easily brought into a fastened state, and the state where both rotors are in a desired phase can be ensured. Can be maintained. Further, when it is not necessary to apply frictional resistance between the two rotors, the pressure contact plate is released from the pressure contact with the friction disk, thereby changing one of the phases when changing the phase between the two rotors. The rotor can be easily rotated without resistance.

Further, in the present invention, the frictional resistance applying means is configured such that the vibration frequency due to the rotation of both rotors or the external vibration frequency transmitted to each rotor depends on the phase between both rotors and the rotation inertia of both rotors. A frictional resistance is imparted between the two rotors at the natural frequency.

When the electric motor of the present invention is mounted on a hybrid vehicle or the like and used as a drive source or a generator, it is conceivable that the vibration of the motor itself or the vibration of an internal combustion engine as another drive source is transmitted to the rotor. When the frequency of these external vibrations matches the natural frequency of the motor (that is, the natural frequency due to the phase between both rotors and the rotational inertia of both rotors), the resonance amplifies the motor vibration. There is a risk of being. Therefore, when in the present invention, the number of external vibration that is transmitted to the frequency or the rotor due to the rotation of both the rotor, a natural frequency by the phase and the rotational inertia of both the rotor between the rotor In addition, since the friction resistance is applied between the two rotors by the friction resistance applying means, the influence of external vibration on the phase displacement between the two rotors can be prevented, and the phase displacement between the two rotors can be stably stabilized. Can be made.

  An embodiment of the present invention will be described with reference to the drawings. First, a first embodiment of the present invention will be described with reference to FIGS. 1 to 3. As shown in FIG. 1, the electric motor 1 according to the first embodiment has an annular outer peripheral rotor 2. And an inner circumferential side rotor 3 disposed concentrically inside the outer circumferential side rotor 2. The outer peripheral rotor 2 includes a plurality of outer peripheral permanent magnets 4 along the circumferential direction. The inner circumferential rotor 3 includes a plurality of inner circumferential permanent magnets 5 arranged along the circumferential direction so as to face each outer permanent magnet 4 of the outer circumferential rotor 2. The outer peripheral rotor 2 is provided so as to be rotatable in the circumferential direction with respect to the inner peripheral rotor 3, and the relative phase with the inner peripheral rotor 3 can be changed by this rotation. Yes. A stator 6 having a plurality of phases of stator windings (not shown) for generating a rotating magnetic field for rotating the outer rotor 2 and the inner rotor 3 is provided on the outer periphery of the outer rotor 2. It has been.

  The electric motor 1 of the present embodiment is a brushless DC motor and is mounted as a drive source in a vehicle such as a hybrid vehicle or an electric vehicle, for example, and the rotating shaft 7 of the electric motor 1 is connected to an input shaft of a transmission (not shown). The driving force of the electric motor 1 is transmitted to driving wheels (not shown) of the vehicle via a transmission.

  When driving force is transmitted from the driving wheel side to the electric motor 1 during deceleration of the vehicle, the electric motor 1 functions as a generator to generate a so-called regenerative braking force, and the kinetic energy of the vehicle body is used as electric energy (regenerative energy). to recover. Further, for example, in a hybrid vehicle, the rotating shaft 7 of the electric motor 1 is connected to a crankshaft of an internal combustion engine (not shown), and the electric motor 1 is a generator even when the output of the internal combustion engine is transmitted to the electric motor 1. Function as a power generation energy.

  As shown in FIG. 1, the outer peripheral side permanent magnet 4 provided on the outer peripheral side rotor 2 is formed in a plate shape and radially arranged so that the thickness direction thereof faces the circumferential direction of the outer peripheral side rotor 2. It is magnetized in the thickness direction (that is, the circumferential direction of the outer rotor 2). Further, the outer peripheral side permanent magnets 4 are arranged so that adjacent ones have different polarities (magnetization directions). That is, an outer peripheral permanent magnet 4 having one N-pole on the circumferential side and an outer permanent magnet 4 having an S-pole on one circumferential side are alternately arranged. The same poles face each other in the circumferential direction.

  Further, the inner peripheral side permanent magnet 5 provided in the inner peripheral side rotor 3 is formed in a plate shape and is disposed so that the thickness direction thereof faces the radial direction of the inner peripheral side rotor 3. Magnetized in the direction (that is, the radial direction of the inner rotor 3). The inner peripheral side permanent magnets 5 are arranged so that the adjacent ones have different polarities (magnetization directions). Specifically, the inner peripheral side permanent magnets 5 whose outer peripheral side is an N pole. And inner peripheral side permanent magnets 5 whose outer peripheral side is an S pole are alternately arranged.

  In addition, as shown in part in FIG. 2, the inner rotor 3 is connected to the rotary shaft 7 via a drive plate 8, and the outer rotor 2 is connected to the rotary shaft 7 with a rotation of a bearing or the like. It is rotatably held via the moving member 9. The rotation range of the outer rotor 2 is restricted by a restriction member 10 provided on the rotation shaft 7. As will be described later, the rotation range is a position where the phase between the outer rotor 2 and the inner rotor 3 is in a strong field state by the outer permanent magnet 4 and the inner permanent magnet 5. To the position where the field weakening state is reached.

  Further, frictional resistance imparting means 11 is provided between the outer peripheral side rotor 2 and the inner peripheral side rotor 3. The frictional resistance imparting means 11 includes a friction disk 12 supported inside the outer rotor 2, a pressure plate 13 supported inside the inner rotor 3 and pressable to the friction disk 12, and a pressure plate And a disc spring member 14 which is a press contact means for pressing 13 to the friction disk 12.

  In addition, the electric motor 1 of this embodiment rotates by supplying a control current to a winding (not shown) of the stator 6 in a state where the outer circumferential rotor 2 and the inner circumferential rotor 3 maintain the rotation speed due to inertia. The relative phase between the outer rotor 2 and the inner rotor 3 can be changed according to the speed of the rotating magnetic field generated in the stator 6 by changing the magnetic field speed. In addition, although not shown, a pair of weights that are separated from each other in the radial direction according to the rotational speed is provided as is well known, and the outer peripheral rotor 2 and the inner peripheral rotor 3 are moved according to the movement of the weight. May be configured to change the relative phases of the outer circumferential rotor 2 and the inner circumferential rotor 3 by rotating in the opposite direction.

  The electric motor 1 configured as described above includes the inner peripheral side permanent magnet 5 of the inner peripheral side rotor 3 at a position corresponding to a position between the pair of adjacent outer peripheral side permanent magnets 4 of the outer peripheral side rotor 2. One is supposed to be located. At this time, as shown in FIG. 3 (a), the pair of adjacent outer peripheral permanent magnets 4 that are adjacent to each other have the same polarity facing each other in the circumferential direction, and the polarity that the both outer peripheral permanent magnets 4 are facing and the inner peripheral side. If the permanent magnet 5 is arranged so that the polarity on the outer peripheral side of the permanent magnet 5 is the same polarity, a strong field state is obtained. On the other hand, when the outer peripheral rotor 2 is rotated from this state, the outer peripheral rotor 2 is displaced with respect to the inner peripheral rotor 3, and as shown in FIG. When the polarities facing each other and the polarities on the outer peripheral side of the inner peripheral side permanent magnet 5 are different from each other, the field weakening state occurs.

  And in the electric motor 1 of this embodiment, the frictional resistance is always provided by the disc spring member 14 of the frictional resistance applying means 11 when the outer peripheral rotor 2 rotates relative to the inner peripheral rotor 3. As a result, for example, since the vehicle is mounted on a vehicle such as a hybrid vehicle or an electric vehicle, vibrations caused by road surface conditions and engine torque fluctuations are transmitted between the inner circumferential rotor 3 and the outer circumferential rotor 2. Even if such a situation occurs, the vibration is attenuated by the frictional resistance, and the inadvertent movement of the outer peripheral rotor 2 with respect to the inner peripheral rotor 3 is suppressed, and the inner peripheral rotor 3 and the outer peripheral rotor 2 are suppressed. Can be maintained in a stable state. Further, since the disc spring member 14 gives a frictional resistance to the rotation of the outer peripheral rotor 2 with respect to the inner peripheral rotor 3, the rotating outer rotor 2 is in contact with the regulating member 10 violently. The occurrence of impact can be prevented.

  Next, a second embodiment of the present invention will be described with reference to FIG. The electric motor 15 according to the second embodiment includes the frictional resistance applying means 16 having a configuration different from that of the electric motor 1 according to the first embodiment, but other configurations and operations are shown in FIG. Since it is the same as that of the electric motor 1 according to the first embodiment, the same reference numerals as those in FIGS. 1 to 3 are given in FIG.

  As shown in FIG. 4, the electric motor 15 according to the second embodiment includes a frictional resistance applying means 16 between the outer peripheral side rotor 2 and the inner peripheral side rotor 3. The frictional resistance imparting means 16 includes a friction disk 17 supported inside the outer rotor 2, a pressure plate 18 supported inside the inner rotor 3 and pressable to the friction disk 17, and a rotating shaft. 7 is configured by a clutch provided with a piston member 19 which is a pressure contact means which is provided so as to be capable of moving forward and backward in the axial direction of 7 and presses the pressure contact plate 18 against the friction disk 17. The piston member 19 forms a pressure chamber 20 between the piston plate 19 and the drive plate 8 of the inner circumferential rotor 3, and a communication hole 22 is connected to the pressure chamber 20 from an oil passage 21 formed inside the rotation shaft 7. The oil for pressurization is supplied through.

Thereby, the pressure chamber 20 is pressurized by the oil supplied through the oil passage 21, and the piston member 19 presses the pressure contact plate 18 against the friction disk 17, so that the outer peripheral side rotor 2 and the inner peripheral side rotor are pressed. Friction resistance can be imparted between 3 and 3. Further, the strength of the frictional resistance can be adjusted by adjusting the hydraulic pressure in the pressure chamber 20. In other words, if the hydraulic pressure in the pressure chamber 20 is relatively small, the rotation of the outer peripheral rotor 2 and the inner periphery of the inner peripheral rotor 3 is permitted while preventing the rotation of the outer rotor 2 with respect to the inner rotor 3. Friction resistance can be applied between the outer rotor 3 and the inner rotor 3 by making the hydraulic pressure in the pressure chamber 20 relatively large. The phases of the outer circumferential rotor 2 and the inner circumferential rotor 3 can be held in a fastening state with a desired phase.

  The piston member 19 is urged by a return spring 23 that urges the pressure plate 18 in a direction opposite to the pressing direction of the pressure plate 18, and when the pressure to the pressure chamber 20 is released, the friction disk 17 of the pressure plate 18 is pressed. The pressure contact is released, and the outer rotor 2 is rotatable with respect to the inner rotor 3.

  The operation of the piston member 19 is performed by a control means (not shown). In the control means, the frequency of the motor 15 itself (the frequency due to the rotation of the outer rotor 2 and the inner rotor 3) or the frequency associated with the torque fluctuation of the internal combustion engine of the hybrid vehicle on which the motor 16 is mounted. Of the outer peripheral side rotor 2 and the inner peripheral side rotor 3 reaches the vicinity of the natural frequency based on the phase and the rotational inertia, and when it matches the natural frequency, the piston member 19 is operated. Thus, a frictional resistance is applied between the outer peripheral side rotor 2 and the inner peripheral side rotor 3, or the phase between the outer peripheral side rotor 2 and the inner peripheral side rotor 3 is held in a fastening state with a desired phase. . Specifically, as an example, the control means refers to a data table showing the relationship between the rotation speed and the vibration frequency of the internal combustion engine, and when the vibration frequency of the internal combustion engine reaches the vicinity of the natural frequency, the piston member 19 Can be activated. Alternatively, the piston means 19 is operated when the frequency of the axle or the like reaches the vicinity of the natural frequency by referring to a data table showing the relationship between the rotational speed and the frequency of the axle or the like during regeneration in the control means. be able to.

  By doing so, even if the frequency transmitted from the outside to the outer peripheral rotor 2 and the inner peripheral rotor 3 matches the natural frequency and resonates, the outer peripheral rotor 2 and the inner peripheral rotor 3 are resonated. And the phase displacement can be satisfactorily stabilized. Furthermore, even if the speed changes suddenly due to acceleration / deceleration depending on the driving situation during traveling of the vehicle, the phase between the outer rotor 2 and the inner rotor 3 can be stably stabilized by applying frictional resistance. While being able to change well, it can prevent reliably that the rotating outer peripheral side rotor 2 contacts the control member 10 violently.

Cross-sectional explanatory drawing which shows typically the principal part structure of the electric motor which concerns on the 1st Embodiment of this invention. Cross-sectional explanatory drawing of the principal part of the electric motor of 1st Embodiment. Explanatory drawing which shows typically the strong field state and weak field state by the phase between both rotors. Cross-sectional explanatory drawing which shows typically the principal part of the electric motor which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,15 ... Electric motor, 2 ... Outer peripheral side rotor (rotor), 3 ... Inner peripheral side rotor (rotor), 4 ... Outer peripheral side permanent magnet (permanent magnet), 5 ... Inner peripheral side permanent magnet (permanent magnet) ), 7... Rotating shaft, 11, 16... Friction resistance applying means, 12, 17... Friction disk, 13, 18, pressure contact plate, 14 .. disc spring member (pressure contact means), 19.

Claims (3)

A pair of rotors in which a plurality of permanent magnets having different polarities are alternately arranged along the circumferential direction are provided concentrically around the rotation shaft, and one rotor rotates the other according to the rotation speed of the rotation shaft. An electric motor in which the relative phase between both rotors is changed by rotating with respect to the child,
E Bei frictional resistance applying means for applying a frictional resistance between the two rotors in one of the rotor rotates relative to the other rotor,
The frictional resistance imparting means imparts frictional resistance between the rotors by bringing the friction disk provided on one rotor, the pressure contact plate provided on the other rotor, and the pressure contact plate against the friction disk. motor, characterized in Rukoto a pressing means for. 2. The electric motor according to claim 1, wherein the press contact means presses the press contact plate against the friction disk at a position where both the rotors are in a predetermined phase, and applies friction resistance between the two rotors. The frictional resistance applying means, frequency from the outside is transmitted to the frequency or the rotor due to the rotation of both the rotor, when due to the phase and the rotational inertia of both the rotor between the two rotors is a natural frequency The electric motor according to claim 1, wherein a frictional resistance is applied between the rotors.

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