JP2009159760A - Electric motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric motor which supplies and discharges an actuating fluid to and from an operating chamber to change a phase and suppresses energy loss resulting from a leak of the actuating fluid from a sealed portion of the operating chamber. <P>SOLUTION: The electric motor includes a phase change mechanism which supplies and discharges the actuating fluid to and from operating chambers 54c and 54d, which are demarcated by a vane fixed to one of first and second rotors and a partition wall 54b fixed to the other of the rotors, to cause at least either of the first and second rotors to rotate around a rotation axis to change a phase representing a relative displacement angle between both rotors. The actuating fluid is made of an electric viscous fluid that increases its viscosity when subjected to an applied voltage. Either of the vane and the partition wall 54a, specifically, the sealed portion 54b of the partition wall 54a includes an electrode 66, specifically, includes a positive electrode 66a for voltage application. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electric motor, and more specifically to an electric motor including a phase change mechanism that changes a phase indicating a relative rotation angle by rotating two magnetized rotors relative to each other.

As an example of an electric motor in which two magnetized rotors are relatively rotated to change the phase indicating the relative rotation angle between them, a technique described in Patent Document 1 below can be cited. In the technique described in Patent Document 1, when the phase of the two rotors is changed according to the rotational speed of the electric motor, the two rotations are performed via a member that is displaced along the radial direction by the action of centrifugal force. One of the children is configured to relatively rotate in the circumferential direction. Also, when the phase is changed according to the speed of the rotating magnetic field generated in the stator, the control current is supplied to the stator winding while the two rotors maintain the rotating speed due to inertia, and the rotating magnetic field speed is increased. By changing, the relative position in the circumferential direction is changed.
JP 2002-204541 A

  By the way, in such an electric motor capable of changing the phase, when the phase is changed by supplying and discharging a working fluid such as oil to the working chamber, it is stopped while balancing with the reaction force torque at the target phase position. However, energy loss may occur due to leakage of the working fluid from the seal portion of the working chamber.

  Accordingly, an object of the present invention is to eliminate the above-described problems, and supply and discharge the working fluid to and from the working chamber to change the phase and suppress energy loss caused by the working fluid leaking from the seal portion of the working chamber. An object is to provide an electric motor.

  In order to achieve the above object, in claim 1, the first and second rotors respectively magnetized, the vane fixed to one of the first and second rotors, and the other A working chamber defined by a partition wall fixed to the working chamber, and a working fluid is supplied to and discharged from the working chamber to rotate at least one of the first and second rotors about a rotation axis. An electric motor having a phase change mechanism for changing a phase indicating a relative displacement angle between the two, wherein the working fluid is composed of an electrorheological fluid whose viscosity increases when a voltage is applied thereto, and either the vane or the partition wall. An electrode for applying the voltage is provided on the seal portion.

  The electric motor according to claim 2, further comprising control means for controlling the characteristics of the electrorheological fluid, wherein the control means outputs the voltage via the electrodes when the phase needs to be maintained. It comprised so that it might apply.

  In the electric motor according to claim 3, the control means is configured to change the applied voltage in accordance with the temperature of the electrorheological fluid.

  In the electric motor according to claim 4, the control means is configured to increase the applied voltage as the temperature of the electrorheological fluid increases.

  In the electric motor according to claim 5, the control means is configured to apply the voltage when it is determined that the phase is changed and the state is stable.

  According to claim 1, the working fluid is supplied to and discharged from a working chamber defined by a vane fixed to one of the first and second rotors magnetized and a partition wall fixed to the other. Then, in the electric motor including the phase change mechanism that changes at least one of the first and second rotors around the rotation axis to change the phase indicating the relative displacement angle between them, the working fluid generates a voltage. It is composed of an electrorheological fluid whose viscosity increases when applied, and an electrode for applying a voltage to the seal part of either the vane or the partition wall is provided, so by applying a voltage through the electrode, By increasing the viscosity of the fluid, it is possible to suppress energy loss caused by leakage of the working fluid from the seal portion of the working chamber.

  In the electric motor according to claim 2, since it is configured to apply a voltage through the electrode when the phase needs to be maintained, in addition to the above-described effect, when the phase needs to be maintained, By applying a voltage through the electrode, the viscosity of the fluid can be increased, and thus energy loss caused by leakage of the working fluid from the seal portion of the working chamber can be suppressed.

  Further, the increase in the viscosity of the fluid in the vicinity of the seal portion of the working chamber increases the friction at that portion, and the amount of fluid necessary to keep the first and second rotors at the phase positions to be held. Energy loss can also be suppressed by reducing itself.

  In the electric motor according to the third aspect, since the applied voltage is changed according to the temperature of the electrorheological fluid, energy loss can be effectively suppressed in addition to the above-described effects.

  In the electric motor according to the fourth aspect, since the voltage to be applied is increased as the temperature of the electrorheological fluid rises, energy loss can be more effectively suppressed in addition to the above-described effects. That is, since the viscosity is inherently high when the temperature of the fluid is low, energy loss including the applied voltage can be more effectively suppressed by reducing the applied voltage. Also, by increasing the applied voltage as the temperature rises, the viscosity of the fluid can be adjusted to a constant, for example, optimum viscosity, so that the stability of the seal can be further ensured and the working fluid can be supplied and discharged. Controllability and energy loss suppression can be achieved even better.

  The electric motor according to claim 5 is configured to apply a voltage when it is determined that the phase is changed and is in a stable state. In addition to the above-described effect, the energy loss is further effectively suppressed. can do. That is, if applied during phase change, the friction increases, but such inconvenience can be avoided by applying in a stable state with the phase changed, thus more effectively suppressing energy loss. be able to.

  The best mode for carrying out the electric motor according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram showing a configuration of an electric motor according to an embodiment of the present invention when mounted on a hybrid vehicle.

  In FIG. 1, reference numeral 10 denotes an electric motor, and the electric motor 10 is mounted on a hybrid vehicle (not shown) together with an internal combustion engine (hereinafter referred to as “engine”) 12. Specifically, the electric motor 10 is composed of a brushless motor or an AC synchronous motor. The engine 12 is a gasoline injection spark ignition type and has four cylinders. The electric motor 10 and the engine 12 are connected to a transmission 16 formed of a CVT (continuously variable transmission) via a drive shaft 14. The transmission 16 shifts the output of the engine 12 and the like, and transmits it to the wheels (drive wheels) 20 to drive the vehicle. Thus, the vehicle is a parallel hybrid vehicle.

  The electric motor 10 always rotates when the engine 12 rotates, and is energized at the time of starting to crank and start the engine 12, and is also energized at the time of acceleration or the like to assist the rotation of the engine 12 (acceleration). When the electric motor 10 is not energized, the motor 10 idles as the engine 12 rotates, and converts the kinetic energy generated by the rotation of the drive shaft 14 into electric energy and outputs it during deceleration when the fuel supply to the engine 12 is stopped. It functions as a generator with a regenerative function.

  The electric motor 10 is connected to a battery 24 via a power drive unit (PDU) 22. The PDU 22 includes an inverter, converts direct current (electric power) supplied (discharged) from the battery 24 to alternating current and supplies the alternating current to the electric motor 10, and converts alternating current generated by the regenerative operation of the electric motor 10 into direct current and converts the direct current (electric power) into direct current. To supply.

  Further, an engine control unit (ENGECU) 26 that controls the operation of the engine 12, a motor control unit (MOTECU) 30 that controls the operation of the electric motor 10, and a state of charge (SOC) of the battery 24 are calculated and charged / discharged. A battery control unit (BATECU) 32 that manages the above and a transmission control unit (T / MECU) 34 that controls the operation of the transmission 16 are provided. All the ECUs (electronic control units) such as the above-described ENGECU 26 are composed of a microcomputer, and are connected to each other via a communication bus 36 so as to be able to communicate with each other.

  Next, the electric motor 10 will be described in detail.

  2 is a cross-sectional view of the main part of the electric motor 10, FIG. 3 is an exploded perspective view showing a phase changing mechanism of the electric motor 10, FIG. 4 is a schematic diagram showing the direction of the magnetic poles of the magnet pieces of the rotor shown in FIG. FIG. 6 is a side view of the rotor of the electric motor 10 shown in FIG. 2, and FIG. 6 is a control block diagram of the electric motor 10.

  As shown in the figure, the electric motor 10 includes an annular stator (stator) 40, a similarly annular rotor 42 housed therein, and a rotation shaft (rotation axis) 44. The stator 40 is formed by laminating thin plates manufactured from iron-based materials (or casting iron-based materials), and is arranged with three-phase (U, V, W-phase) stator windings 40a.

  The rotor 42 includes an outer peripheral (first) rotor 42 a and an inner peripheral (second) rotor 42 b that is relatively rotatable or relatively displaceable about a rotating shaft (rotating axis) 44. The rotors 42a and 42b are made of, for example, iron cores made of sintered metal, and a plurality of sets, more precisely 16 sets of magnet pieces (permanent magnets) 46 are spaced slightly from each other on the circumferential side. Arranged.

  As shown in FIGS. 2 and 3, the rotor 42 is provided with a phase changing mechanism 50. The phase changing mechanism 50 includes a vane rotor 52 that is fixed to the rotating shaft 44 via a spline (not shown), an annular housing 54 that is fitted and fixed to the inner peripheral surface of the rotor 42b on the inner peripheral side, A pair of drive plates 56 that fix the vane rotor 52 to the rotor 42a on the outer peripheral side with pins 56a, and a fluid supply mechanism 60 (see FIG. 6) that supplies working fluid, more specifically ER (electric) viscous fluid thereto. Is shown). The vane rotor 52 and the annular housing 54 are also made of sintered metal.

  As shown in FIG. 3, the vane rotor 52 is formed with a plurality of (six) vanes 52 a projecting from the central boss portion at equal intervals in the radial direction, and the annular housing 54 has a central side. A plurality of (six) partition walls 54a projecting at equal intervals are formed. Seal portions (seal members) 52b and 54b are disposed at the tips of the vane 52a and the partition wall 54a, respectively.

  The seal portion 52b is disposed at the tip of the vane 52a and abuts against the inner peripheral surface 54b1 of the annular housing 54 to seal between the vane 52a and the inner peripheral surface 54b1 in a liquid-tight manner. The seal portion 54b is disposed at the tip of the partition wall 54a and abuts on the outer peripheral surface 52b1 of the boss portion of the vane rotor 52 to seal between the partition wall 54a and the outer peripheral surface 52b1 of the boss portion in a liquid-tight manner.

  As shown in FIG. 2, the annular housing 54 has an axial length (width) larger than that of the rotor 42b on the inner peripheral side, and an annular groove 56b (FIG. 3) formed in the two drive plates 56. The annular housing 54 and the inner peripheral rotor 42b are rotatably supported by the outer peripheral rotor 42a and the rotating shaft 44.

  The two drive plates 56 are slidably brought into close contact with both side surfaces of the annular housing 54, and a plurality of sealed spaces (6) are formed between the partition wall 54a of the annular housing 54 and the outer peripheral surface 52b1 of the boss portion of the vane rotor 52. To form). This sealed space is divided into two by a vane 52a of the vane rotor 52, and forms an advance side working chamber (first working chamber) 54c and a retard side working chamber (second working chamber) 54d. Here, the “advance angle” (ADV) means that the inner rotor 42b is moved in the same direction as the rotation direction of the electric motor 10 indicated by an arrow ADV (FIG. 5) with respect to the outer rotor 42a. “Angle” (RTD) means relative rotation in the opposite direction.

  The advance-side working chamber 54c and the retard-side working chamber 54d are supplied with fluid, specifically, the above-described ER (electric) fluid (Electro-rheological fluid; hereinafter abbreviated as “ER fluid”). The ER fluid is obtained by adding insulating fine particles to an insulating liquid (silicon oil), for example, and has a characteristic that viscosity (rheological behavior) increases when a voltage is applied.

  In the fluid supply mechanism 60 shown in FIG. 6, ER fluid is pumped up from a reservoir 60a by a pump 60c driven by an electric motor 60b, and passes through an ER fluid supply circuit (not shown) inserted through an electromagnetic solenoid valve. It is pumped to the rotating shaft 44. As shown in FIG. 2, the ER fluid pressure-fed to the rotary shaft 44 passes through the two fluid passages (oil passages) 62 and 64 formed in the vane rotor 52 from the rotary shaft 44, and the advance-side working chamber 54 c and the slow-action chamber 54 c. It is supplied to the corner side working chamber 54d.

  The fluid passages 62 and 64 are substantially parallel to each other. As shown in FIGS. 2 and 5, the fluid passages 62 a and 64 a drilled in the axial direction of the rotating shaft 44, and the outer peripheral surface of the rotating shaft 44 continuously therewith. The fluid passages 62b and 64b are formed, and the fluid passages 62c and 64c are formed continuously in the boss portion of the vane rotor 52. The fluid path 62 is connected to the advance side working chamber 54c, and the fluid path 64 is connected to the retard side working chamber 54d, and the ER fluid is supplied to and discharged from the reservoir 60a (FIG. 6).

  The advance-side working chamber 54c and the retard-side working chamber 54d expand and contract as ER fluid is supplied and discharged, so that the inner periphery integrated with the partition wall 54a with respect to the vane 52a fixed to the outer rotor 42a. The phase of the relative rotation angle or displacement angle between the outer peripheral side rotor 42a and the inner peripheral side rotor 42b is caused by the relative rotation of the side rotor 42b about the rotation axis (rotation axis) 44. It is changed between 0 degrees and 180 degrees, and the induced voltage of the electric motor 10 is changed accordingly.

  FIG. 5 shows the advance side working chamber 54c and the retard side working chamber 54d at the most advanced position. In the electric motor 10 according to this embodiment, when the inner circumferential rotor 42b is at the most retarded position (phase 0 degree) with respect to the outer circumferential rotor 42a, as shown in FIG. In addition, the magnet pieces 46 have the same poles facing each other to form a strong field (increase in the field), while the inner circumferential side rotor 42b is at the most advanced angle position (with respect to the outer circumferential side rotor 42a). When the phase is 180 degrees, as shown in FIG. 4 (b), the magnet pieces 46 face each other and become a weak field (the field is reduced).

  Thereby, the induced voltage constant Ke of the electric motor 10 is changed, and the characteristics of the electric motor 10 are changed. That is, when the induced voltage constant Ke increases due to the strong field, the allowable rotational speed at which the motor 10 can operate decreases, but the maximum torque that can be output increases, and conversely, when the induced voltage constant Ke decreases due to the weak field. The maximum torque that can be output decreases, and the allowable rotational speed increases.

  The electric motor 10 is stable when the inner rotor 42b is at the most retarded position (phase 0 degree) with respect to the outer rotor 42a. That is, when the ER fluid is not supplied, the rotor 42 is relatively displaced toward the most retarded position, and stops at a position that balances the reaction torque.

  What is characteristic of the electric motor 10 according to this embodiment is that a voltage is applied to the ER fluid to either the vane 52a of the vane rotor 52 or the partition wall 54a of the annular housing 54, more specifically, to the partition wall 54a. The electrode 66 is provided.

  That is, as shown in FIGS. 7 and 8, the electrode 66 is provided in the vicinity of the seal portion 54 b disposed at the tip of the partition wall 54 a of the annular housing 54. The electrode 66 includes an anode 66a made of copper foil attached to both sides of the seal portion 54b, and a cathode 66b formed by grounding the outer peripheral surface 52b1 of the boss portion in contact with the anode 66a (see FIGS. 7 and 8). The thickness of the anode 66a made of foil is exaggerated).

  The anode 66a is connected to the battery 24 via the electric wire 68, and is configured such that a voltage can be applied between the anode 66a and the cathode 66b formed of the outer peripheral surface 52b1 of the boss portion with which the seal portion 54b abuts. When a voltage is applied, the viscosity of the ER fluid filling the vicinity of the anode 66a and the cathode 66b, that is, the portion indicated by the broken line in FIG. 8, is increased.

  Next, the control of the electric motor 10 will be described with reference to FIG. The illustrated control is executed by the MOTECU 30.

  The outline of the control shown in the drawing is as follows. The magnetic flux direction of the field pole of the permanent magnet 46 of the rotor 42 is d axis (field axis), and the direction orthogonal thereto is q axis (torque axis). Current feedback control is performed on the dq coordinates that form the rotation orthogonal coordinates that rotate in synchronization with the rotation phase of the current.

  That is, the current command calculation unit 30a calculates the torque T calculated based on the accelerator opening detected by an accelerator opening sensor (not shown) and the rotation angle θm of the electric motor 10 detected by the rotation angle sensor 30b. The rotational speed Nm of the electric motor 10 calculated by differentiating by the differentiator 30c and the induced voltage constant Ke calculated by the Ke calculator 30d are input, and based on them, the PDU 22 should be supplied to the stator winding 40a. An Id command and an Iq command, which are current commands for the d and q axes for designating the three-phase currents Iu, Iv, and Iw, are calculated.

  In the next stage of the current command calculation unit 30a, a weakening is performed so as to control the current phase so that the field quantity of the rotor 42 is equivalently weakened in order to suppress an increase in the back electromotive voltage accompanying an increase in the motor rotation speed Nm. A field control unit 30f that outputs a field current target value as a d-axis correction current and a power control unit 30g that outputs a q-axis correction current according to the remaining capacity of the battery 24 and the like are connected.

  Accordingly, the current commands Id and Iq are added with the d-axis correction current and the q-axis correction current in the next addition / subtraction stages 30i and 30j, and are output from the three-phase-dq conversion unit 30k (described later). Deviations ΔId and ΔIq are calculated by subtracting Id and q-axis current Iq and output to current FB control unit 30l.

  The current FB control unit 30l amplifies the deviations ΔId and ΔIq by, for example, PI operation corresponding to the motor rotation speed Nm, calculates the d-axis voltage command value Vd command and the q-axis voltage command value Vq command, and dq-3 phase The data is output to the conversion unit 30m.

  The dq-3 phase converter 30m uses the rotation angle θm of the electric motor 10 output from the rotation angle sensor 30b to convert the d-axis voltage command Vd and the q-axis voltage command Vq on the dq coordinate to the three-phase that is a stationary coordinate. It converts into the voltage command value Vu, Vv, Vw which is a voltage command value on an alternating current coordinate, and outputs it to the PWM calculating part 30n.

  The PWM calculation unit 30n is a gate signal for turning on / off each switching element of the PWM inverter of the PDU 22 by pulse width modulation based on the three-phase output voltages (sine waves) Vu, Vv, Vw, the carrier signal (triangular wave), and the switching frequency. (PWM signal) is generated and supplied to the stator winding 40a.

  The currents Iu, Iv, and Iw of each phase are detected by the current sensors 30o and 30p, and the detected values are sent to the three-phase-dq conversion unit 30k after the noise is removed by the BP filter 30q. The three-phase-dq conversion unit 30k calculates a rotation coordinate based on the rotation phase of the motor 10, that is, a d-axis current Id and a q-axis current Iq on the dq coordinate, based on the filter output and the motor rotation angle θm. As described above, the deviation is calculated based on the calculated value.

  Further, the Ke command calculation unit 30r outputs a Ke command that is a command value of the induced voltage constant Ke of the motor 10 based on the torque command T, the motor rotation speed Nm, and the motor power supply voltage (voltage of the battery 4) Vdc. On the other hand, the phase changed through the fluid supply mechanism 60 (the relative displacement angle between the inner circumferential rotor 42b and the outer circumferential rotor 42a) is detected as the current phase θ by the phase sensor 30s, and Ke is calculated. Sent to the unit 30d. The Ke calculation unit 30d calculates an induced voltage constant Ke based on the input current phase θ and sends it to the addition / subtraction stage 30t and also to the current command calculation unit 30a.

  In the addition / subtraction stage 30t, the induced voltage constant Ke is subtracted from the output Ke command, and the obtained difference ΔKe is input to the phase control unit 30u. The phase control unit 30u determines the phase so that the difference ΔKe decreases, and controls the operation of the fluid supply mechanism 60 based on the phase.

  Reference numeral 30v denotes an ER fluid characteristic control unit. The ER fluid characteristic control unit 30v functionally represents a process of executing characteristic change by voltage application of the ER fluid in the operation of the MOTECU 30.

  The ER fluid characteristic control unit 30v outputs the current phase detected by the phase sensor 30s (relative rotation angle or displacement angle between the inner circumferential side rotor 42b and the outer circumferential side rotor 42a) θ and the phase control unit 30u outputs And an output of a temperature sensor 30w that is arranged near the reservoir 60a and generates an output indicating the temperature of the ER fluid.

  FIG. 9 is a flowchart showing the operation of the electric motor according to this embodiment, specifically the operation of the MOTECU 30, more specifically the operation of the ER fluid characteristic control unit 30v. The illustrated program is executed every predetermined time, for example, every 10 msec.

  In the following, in S10, the previous phase command value θBT (the value of the phase command value θT at the time of the previous program execution) is read, and the process proceeds to S12, and the current (current) phase command value θT (the value at the time of the current program execution) The process proceeds to S14, and it is determined whether or not both are equal, in other words, whether or not the phase change is completed and the phase needs to be maintained.

  When the result is affirmative in S14, the process proceeds to S16, and an average value ∫θ for a predetermined time of the phase θ, for example, 5 seconds is calculated. The process proceeds to S18, and the detected current (current) phase θ is equal to the average value ∫θ. Determine whether or not. If the average value ∫θ of the phase over 5 seconds is equal to the current phase θ, it means that the phase is in a stable state, and therefore the processing of S18 determines whether or not the phase is changed and is in a stable state. It corresponds to doing.

  When the result in S18 is affirmative, the program proceeds to S20, and the seal portion application voltage TAV is calculated. That is, the voltage to be applied to the electrode 66 (anode 66a) of the seal portion 54b of the partition wall 54a of the annular housing 54 is calculated.

  FIG. 10 is a sub-routine flowchart showing the calculation process of the seal portion applied voltage TAV.

  Explained below, the temperature TER of the ER fluid detected from the output of the temperature sensor 30w is read in S100, and the process proceeds to S102, where the applied voltage γV is calculated by searching the characteristics shown in FIG. 11 from the read temperature TER of the ER fluid. In S104, the calculated applied voltage γV is set as the seal portion applied voltage TAV.

  As shown in FIG. 11, the seal portion applied voltage TAV (applied voltage γV) is changed according to the temperature TER of the ER fluid, and more specifically, is determined to increase as the temperature TER of the ER fluid increases. The This is because the viscosity is inherently high in the region where the temperature TER of the ER fluid is low, and therefore the applied voltage is small.

  Returning to the description of the flowchart of FIG. 9, the process proceeds to S22, and the calculated seal portion application voltage TAV is applied to the electrode 66 (anode 66a) of the seal portion 54b. As a result, the viscosity of the ER fluid filling the vicinity of the anode 66a and the cathode 66b increases, and leakage of the ER fluid from the gap between the seal portion 54b and the outer peripheral surface 52b1 of the boss portion can be suppressed.

  When the result in S14 is negative, the phase change is not completed and the phase is not required to be maintained, so that the process proceeds to S24 and no voltage is applied to the electrode 66 (anode 66a) of the seal portion 54b. And Even when the result in S18 is NO, the phase is not in a stable state, so the process proceeds to S24.

  In the electric motor according to this embodiment, as described above, the first and second rotors 42a and 42b magnetized, and the vane 52a fixed to one of the first and second rotors, respectively. And working chambers 54c and 54d defined by the partition wall 54b fixed to the other, and supply and discharge of the working fluid to and from the working chamber, so that at least one of the first and second rotors 42a and 42b is provided. In the electric motor 10 including the phase changing mechanism 50 that changes the phase θ indicating the relative displacement angle by rotating about the rotation axis 44, the viscosity increases when the working fluid is applied with a voltage. And an electrode 66 for applying the voltage to one of the vane 52a and the partition wall 54a, more specifically to the seal portion 54b of the partition wall 54a. In Since the electrode 66a is provided, a voltage is applied through the electrode 66 to increase the viscosity of the electrorheological fluid, and thus energy loss caused by leakage of the electrorheological fluid from the seal portions 54b of the working chambers 54c and 54d. Can be suppressed.

  In addition, control means (MOT ECU 30, ER fluid characteristic control unit 30v, S10 to S24) for controlling the characteristics of the electrorheological fluid is provided, and the control means, when the phase needs to be maintained, the electrode 66 Since the voltage is applied via the electrode 66 (S14, S22), when the phase needs to be maintained, the voltage of the electrorheological fluid can be increased by applying the voltage via the electrode 66. Therefore, energy loss caused by leakage of the electrorheological fluid from the seal portion 54b of the working chambers 54c and 54d can be suppressed.

  Further, since the viscosity of the electrorheological fluid in the vicinity of the seal portion 54b of the working chambers 54c and 54d increases, the friction at that portion increases, and the phase position where the first and second rotors 42a and 42b should be held is increased. It is also possible to suppress energy loss by reducing the amount of electrorheological fluid required to maintain the same.

  Further, since the control means is configured to change the applied voltage according to the temperature TER of the electrorheological fluid (S20, S100 to S104), in addition to the above-described effects, energy loss is effectively suppressed. be able to.

  Further, since the control means is configured to increase the applied voltage as the temperature TER of the electrorheological fluid increases (S20, S100 to S104), in addition to the above-described effects, the energy loss is more effectively reduced. Can be suppressed. That is, since the viscosity is inherently high when the temperature of the electrorheological fluid is low, energy loss including the applied voltage can be more effectively suppressed by reducing the applied voltage. Further, by increasing the voltage to be applied as the temperature rises, the viscosity of the electrorheological fluid can be adjusted to a constant value, for example, the optimum viscosity, so that the stability of the seal can be further ensured, and the fluid supply mechanism The controllability of 60 and the suppression of energy loss can be adjusted so as to achieve better.

  Further, since the control means is configured to apply the voltage (S14 to S22) when it is determined that the phase is changed and is in a stable state, in addition to the above-described effects, energy loss can be further improved. Can be suppressed. That is, if applied during phase change, the friction increases, but such inconvenience can be avoided by applying in a stable state with the phase changed, thus more effectively suppressing energy loss. be able to.

  In the above description, the anode 66a is provided in the vicinity of the seal portion 54b of the partition wall 54a of the annular housing 54, and the outer peripheral surface 52b1 of the boss portion of the vane rotor 52 is grounded to form the cathode 66b, but the vane 52a of the vane rotor 52 is sealed. An anode may be provided near the portion 52b, and the inner peripheral surface 54b1 of the annular housing 54 may be grounded to serve as a cathode.

  Further, the electric motor according to the present invention has been described by taking the electric motor mounted on the parallel hybrid vehicle as an example. However, the present invention relates to the electric motor mounted on the series hybrid vehicle, and further the electric motor mounted on the electric vehicle not including the internal combustion engine. Also valid.

  In addition, at least one of the first and second rotors, more specifically, the second rotor 42b is relatively rotated about the rotation axis (rotation axis 44), and the relative rotation angle or displacement angle of both is thereby increased. Although the phase θ shown is changed, the phase may be changed by relatively rotating both the first and second rotors.

It is the schematic which mounts and shows the electric motor which concerns on the Example of this invention as a drive source of a hybrid vehicle. It is principal part sectional drawing of the electric motor shown in FIG. It is a disassembled perspective view which shows the phase change mechanism of the electric motor shown in FIG. It is a schematic diagram which shows the direction of the magnetic pole of the magnet piece of the rotor shown in FIG. FIG. 3 is a side view of the rotor shown in FIG. 2. It is a block diagram which shows control of the electric motor by the motor control unit (MOTECU) shown in FIG. FIG. 2 is an explanatory perspective view of the vicinity of a seal portion of a partition wall that defines the working chamber of the electric motor shown in FIG. 1 and the like. FIG. 8 is an explanatory top view of the vicinity of the seal portion of the partition wall shown in FIG. 7. 7 is a flowchart showing the operation of the ER fluid characteristic control unit of the block diagram of FIG. 6. FIG. 10 is a sub-routine flowchart showing a calculation process of the seal portion application voltage TAV in the flowchart of FIG. 9; FIG. 11 is an explanatory graph showing characteristics of a seal portion application voltage TAV used in the processing of the flowchart of FIG. 10.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Electric motor (electric motor), 12 Engine (internal combustion engine), 30 Motor control unit (MOTECU), 30v ER fluid characteristic control part, 30w Temperature sensor, 40 Stator, 42 Rotor, 42a Outer peripheral side (first) rotation Child, 42b inner peripheral side (second) rotor, 44 rotation shaft (rotation axis), 46 magnet piece, 50 phase change mechanism, 52 vane rotor, 52a vane, 52b seal portion, 52b1 outer peripheral surface, 54 annular housing, 54a Partition wall, 54b seal portion, 54b1 inner peripheral surface, 54c advance side working chamber (first working chamber), 54d retard side working chamber (second working chamber), 56 drive plate, 62, 64 fluid path, 60 Fluid supply mechanism, 66 electrode, 66a anode, 66b cathode, 68 electric wire

Claims (5)

  A working chamber defined by first and second rotors respectively magnetized; a vane fixed to one of the first and second rotors; and a partition wall fixed to the other; A phase changing mechanism for supplying and discharging the working fluid to and from the working chamber and rotating at least one of the first and second rotors about the rotation axis to change a phase indicating a relative displacement angle between them; In the electric motor, the working fluid is made of an electrorheological fluid whose viscosity increases when a voltage is applied, and an electrode for applying the voltage is provided to any one of the seal portion of the vane and the partition wall. Features an electric motor.   2. The control means for controlling the characteristics of the electrorheological fluid, wherein the control means applies the voltage through the electrode when the phase needs to be maintained. Electric motor.   The electric motor according to claim 2, wherein the control unit changes the applied voltage according to a temperature of the electrorheological fluid.   The electric motor according to claim 3, wherein the control unit increases the applied voltage as the temperature of the electrorheological fluid increases.   5. The electric motor according to claim 2, wherein the control unit applies the voltage when it is determined that the phase is changed and is in a stable state. 6.

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