JP6250574B2 - Electromagnetic damper - Google Patents

Description

  The present invention relates to an electromagnetic damper in which external vibration is input to an output shaft of an electric motor and a damping force for the external vibration is generated by the electric motor.

  Patent Document 1 aims to improve the riding comfort of a vehicle even in a shock absorber that generates a damping force using the electromagnetic force of a motor ([0007], summary). The shock absorber D of Patent Document 1 includes a motion conversion mechanism T that converts linear relative motion between the vehicle body B and the axle into a rotational motion, and a motor M that transmits the rotational motion converted by the motion conversion mechanism T. In the shock absorber D, the motor M is fixed to the vehicle body B side, and a motion conversion mechanism T is interposed between the vehicle body B and the axle, reducing the weight of the spring upper connection mass and reducing vibration from the axle side. The force for transmitting the input to the vehicle body B side is reduced. This improves riding comfort in the vehicle (summary).

  The motor M is connected to a control device (not shown) and an external power source so that the rotational torque of the rotor 1 can be controlled, and is adjusted to obtain a desired damping force. In addition, the motor M is actively driven to cause the shock absorber D to function not only as a shock absorber but also as an actuator ([0016]).

JP 2006-056768 A

  In the shock absorber D (electromagnetic damper) of Patent Document 1, when the motion conversion mechanism T converts the linear relative motion between the vehicle body B and the axle to a rotational motion, when the rotor 1 of the motor M generates a rotational torque, etc. Inertial force (or moment of inertia) is generated. In the configuration in which the inertial force is relatively large, the inertial force inhibits the change in the stroke of the shock absorber D when the acceleration of the input to the shock absorber D (for example, the input from the road surface) is large. Along with this, there is a possibility that the vibration damping function by the shock absorber D is not sufficiently exhibited (for example, when the shock absorber D is used in a vehicle suspension device, the ride comfort of the vehicle is deteriorated).

  The present invention has been made in view of the above-described problems, and an object thereof is to provide an electromagnetic damper capable of improving vibration damping characteristics.

  An electromagnetic damper according to the present invention inputs external vibration to an output shaft of an electric motor and generates a damping force against the external vibration in the electric motor, and transmits the output shaft of the electric motor or the external vibration to the electric motor. Torque detecting means for detecting torsional torque of the transmission shaft and a control device for controlling the electric motor, wherein the control device controls the electric motor so as to cancel the torsional torque detected by the torque detecting means. It is characterized by that.

  According to the present invention, the motor is controlled so as to cancel the torsion torque of the transmission shaft that transmits the output shaft of the motor or external vibration to the motor. The torsion torque includes disturbance factors such as inertia force. For this reason, by transmitting the power of the motor to the output shaft or the transmission shaft while suppressing the torsional torque, it becomes possible to reduce the influence of disturbance factors and more reliably realize the target value of the power of the motor. As a result, it is possible to improve the vibration damping characteristics of the electromagnetic damper (for example, when the electromagnetic damper is provided in a vehicle suspension device, the riding comfort of the vehicle can be improved).

  Further, in the configuration in which the torque detection means detects the torsional torque of the output shaft of the electric motor, when the inertia ratio of the electric motor (rotor or the like) occupies the inertia of the entire electromagnetic damper, it is easy to cancel out the inertia of the electric motor. It becomes possible.

  The electromagnetic damper includes a screw shaft as the transmission shaft and a nut screwed with the screw shaft, and converts the linear motion of the nut relative to the screw shaft into a rotational motion of the screw shaft. Rotational motion may be transmitted to the output shaft of the electric motor.

  Alternatively, the electromagnetic damper includes a rack gear formed on the transmission shaft side and a pinion gear formed on the output shaft side of the electric motor, and the linear motion of the transmission shaft is rotated by the rack gear and the pinion gear. The rotational movement of the pinion gear may be transmitted to the output shaft of the electric motor.

  Alternatively, the electromagnetic damper may include a rotating arm that rotates about the output shaft of the electric motor, and the torque detecting means may detect the torsional torque of the output shaft of the electric motor or the rotating arm.

  The electromagnetic damper may be provided in a vehicle suspension device. In that case, the control device may reduce the degree of cancellation of the twisting torque in accordance with an increase in the steering angle or the steering angular speed of the steering. As a result, when the vehicle travels, for example, on a curved road, the influence of inertial force remains relatively, and the damping force of the electromagnetic damper can be reduced. Therefore, it is possible to improve riding comfort and improve steering response or steering stability.

  The control device may reduce the degree of cancellation of the twisting torque in accordance with an increase in the vehicle speed of the vehicle. As a result, the degree of cancellation of the twisting torque is reduced as the vehicle speed increases, so that it is possible to ensure the stability of the vehicle in the high vehicle speed region.

  The control device includes a reference control amount calculation unit that calculates a reference control amount of the electric motor, a correction control amount calculation unit that corrects the reference control amount to calculate a correction control amount, and the correction control amount based on the correction control amount. You may provide the electric motor control part which controls an electric motor. The correction control amount calculation unit may calculate the correction control amount by reflecting a difference between the twisting torque and a torque corresponding to the reference control amount in the reference control amount. As a result, it is possible to accurately exclude the disturbance factor included in the twisting torque.

  The torque detection means can be, for example, a magnetostrictive torque sensor. Thereby, it becomes possible to detect the torsion torque in the output shaft or transmission shaft of the electric motor with high accuracy.

  According to the present invention, it is possible to improve the vibration damping characteristics of the electromagnetic damper.

It is a figure showing simply a part of vehicles carrying an electromagnetic damper concerning one embodiment of the present invention. It is a flowchart which shows the whole flow of control of the electronic control apparatus of the said embodiment. It is a block diagram which shows the structure for controlling the motor in the said embodiment centering on calculation of correction | amendment control amount. It is a figure which shows an example of the content of the vehicle speed-1st gain map in the said embodiment. It is a figure which shows an example of the content of the steering angular velocity-2nd gain map in the said embodiment. It is a figure which shows simply a part of vehicle which mounts the electromagnetic damper which concerns on the 1st modification of this invention. It is a figure which shows simply a part of vehicle which mounts the electromagnetic damper which concerns on the 2nd modification of this invention. It is a figure which shows simply a part of vehicle which mounts the electromagnetic damper which concerns on the 3rd modification of this invention. It is a figure which shows the modification of arrangement | positioning of a torque sensor.

A. One Embodiment [A1. Configuration of Vehicle 10]
(A1-1. Overall configuration of vehicle 10)
FIG. 1 is a diagram schematically showing a part of a vehicle 10 equipped with an electromagnetic damper 12 (hereinafter also referred to as “damper 12”) according to an embodiment of the present invention. The damper 12 of the present embodiment constitutes a part of the suspension device of the vehicle 10. The suspension device includes a spring (for example, a coil spring) in addition to the damper 12. The vehicle 10 further includes sensors 14 and a battery 16. The dampers 12 are provided on both front wheels (left front wheel, right front wheel) and rear wheels (left rear wheel, right rear wheel). Alternatively, the damper 12 may be provided only on the front wheel or only on the rear wheel.

  The sensors 14 include a torque sensor 20, a vehicle speed sensor 22, a steering angle sensor 24, and a current sensor 26. The torque sensor 20 detects a twisting torque Td (hereinafter also referred to as “torque Td” or “detected torque Td”) applied to a part of the damper 12 (an output shaft 60 of a motor 56 described later).

  As the torque sensor 20 of the present embodiment, for example, a magnetostrictive torque sensor can be used. In addition, in order to show the position of the torque sensor 20 in the damper 12 (particularly, the damper main body 30) while showing that the torque sensor 20 is included in the sensors 14, the torque sensor 20 is shown in two places in FIG. Both are the same.

  The vehicle speed sensor 22 detects the vehicle speed V [km / h] of the vehicle 10. The steering angle sensor 24 detects the steering angle θst [°] of the steering 28. The current sensor 26 detects the input / output current (hereinafter referred to as “motor current Imot”) [A] of the motor 56 of the damper 12. In addition, since the motor 56 of the present embodiment is a three-phase AC motor, the current sensor 26 detects currents of a plurality of phases (U phase, V phase, W phase) and dq-converts these currents. Motor current Imot is calculated as d-axis current (torque component).

  The battery 16 is, for example, a lead storage battery, but may be another power source or a power storage device (for example, a lithium ion battery, a generator, a fuel cell, or a capacitor).

(A1-2. Damper 12)
(A1-2-1. Overview of damper 12)
As shown in FIG. 1, the damper 12 includes a damper main body 30, an inverter 32, and an electronic control device 34 (hereinafter referred to as “ECU 34”).

(A1-2-2. Damper body 30)
(A1-2-2-1. Outline of Damper Body 30)
As shown in FIG. 1, the damper main body 30 includes a connecting portion 40, an inner tube 42, and a nut 44 as members on the wheel side (not shown). The damper main body 30 includes an outer tube 50, a screw shaft 52, a bearing 54, and a motor 56 as members on the vehicle body 58 side.

  The connecting portion 40 is connected to a wheel by being fixed to a knuckle (not shown) of the suspension device. When external vibration is input to the connecting portion 40 from the wheel side and thrust is applied to the connecting portion 40 in FIG. 1, for example, upward (in the so-called dump direction), the inner tube 42 and the nut 44 are applied to the outer tube 50. Ascending, the screw shaft 52 rotates. At this time, it is possible to attenuate the vibration of the spring of the suspension device by generating a reaction force from the motor 56 to the screw shaft 52.

  As a basic configuration of the damper main body 30, an existing one (for example, see Patent Document 1) can be used.

(A1-2-2-2. Motor 56)
The motor 56 of the present embodiment is a three-phase AC brushless type, but is not limited thereto. The output shaft 60 of the motor 56 is connected or fixed to the screw shaft 52 via a coupling 62. The motor 56 generates power (reaction force) on the screw shaft 52 based on electric power supplied from the battery 16 in response to a command from the ECU 34. Further, the motor 56 may output the electric power generated by performing power generation (regeneration) based on the force input to the screw shaft 52 from the wheel side to the battery 16.

(A1-2-3. Inverter 32)
The inverter 32 has a three-phase full-bridge type configuration, performs DC / AC conversion, converts DC to three-phase AC, and supplies the same to the motor 56. The inverter 32 may supply direct current after alternating current / direct current conversion accompanying the regenerative operation to the battery 16.

(A1-2-4.ECU34)
As shown in FIG. 1, the ECU 34 includes an input / output unit 70, a calculation unit 72, and a storage unit 74. The input / output unit 70 inputs and outputs signals to and from the sensors 14 and the inverter 32.

  The calculation unit 72 controls each part of the damper 12, and includes a reference control amount calculation unit 80, a correction control amount calculation unit 82, and a motor control unit 84. In the present embodiment, the reference control amount calculation unit 80, the correction control amount calculation unit 82, and the motor control unit 84 are realized by executing a control program stored in the storage unit 74.

  The reference control amount calculation unit 80 calculates a reference control amount Uref for the motor 56. The reference control amount Uref is a variable reference value (value before correction) for controlling the motor 56, and in this embodiment, is the target reference force Fref_tar [N]. The target reference force Fref_tar is a reference value for the force generated by the motor 56.

  The correction control amount calculation unit 82 corrects the reference control amount Uref to calculate the correction control amount Ucor. The corrected control amount Ucor is obtained by correcting the reference control amount Uref in order to cancel disturbance factors such as inertia, and is the target motor current Imot_tar in this embodiment. The motor control unit 84 controls the motor 56 via the inverter 32 based on the correction control amount Ucor.

  The storage unit 74 stores various programs and data such as a control program used in the calculation unit 72.

[A2. Control in this embodiment]
(A2-1. Overall flow)
FIG. 2 is a flowchart showing an overall flow of control of the ECU 34 of the present embodiment. In step S1, the reference control amount calculation unit 80 of the ECU 34 calculates a reference control amount Uref. In step S2, the correction control amount calculation unit 82 of the ECU 34 calculates the correction control amount Ucor. In step S3, the motor control unit 84 of the ECU 34 controls the motor 56 by operating the inverter 32 based on the correction control amount Ucor.

(A2-2. Calculation of reference control amount Uref)
As described above, the reference control amount Uref is a variable reference value for controlling the motor 56, and in this embodiment, is the target reference force Fref_tar [N]. For example, the ECU 34 calculates the reference control amount Uref by the same method as in Japanese Patent Application Laid-Open No. 2004-237824 or Japanese Patent Application Laid-Open No. 2009-078761.

(A2-3. Calculation of correction control amount Ucor)
(A2-3-1. Basic concept)
The correction control amount Ucor of the present embodiment is used to cancel disturbance factors such as inertia of the damper main body 30. In the present embodiment, the inertia of the rotor 56 of the motor 56 (hereinafter also referred to as “motor rotor”) (not shown) in the damper main body 30 is relatively large. For this reason, it becomes possible to make the output of the motor 56 easily approach the reference control amount Uref (target reference force Fref_tar) by canceling the inertia in the motor rotor.

(A2-3-2. Specific processing)
(A2-3-2-1. Overview)
FIG. 3 is a block diagram showing a configuration for controlling the motor 56 in the present embodiment, centering on the calculation of the correction control amount Ucor. As shown in FIG. 3, the correction control amount calculation unit 82 of the ECU 34 includes a target motor current calculation unit 100, a vehicle speed reflection correction unit 102, and a steering angle reflection correction unit 104.

(A2-3-2-2. Target motor current calculation unit 100)
Target motor current calculation unit 100 (hereinafter also referred to as “calculation unit 100”) calculates target motor current Imot_tar as correction control amount Ucor. As illustrated in FIG. 3, the calculation unit 100 includes a first current converter 110, a torque converter 112, a first subtractor 114, a second current converter 116, and a second subtractor 118.

  The first current converter 110 converts the target reference force Fref_tar [N] as the reference control amount Uref into a current value (target reference current Iref_tar) [A]. The torque converter 112 converts the target reference force Fref_tar into a torque value (target reference torque Tref_tar) [Nm].

  The first subtractor 114 calculates a difference ΔT1 between the second correction torque Tc2 output from the steering angle reflection correction unit 104 and the target reference torque Tref_tar from the torque converter 112. The second current converter 116 converts the difference ΔT1 [Nm] calculated by the first subtractor 114 into a current value (F / B current Ifb) [A]. The second subtractor 118 calculates the difference between the target reference current Iref_tar from the first current converter 110 and the F / B current Ifb from the second current converter 116 as the target motor current Imot_tar, and the motor control unit 84. Output to.

(A2-3-2-2. Vehicle speed reflection correction unit 102)
The vehicle speed reflection correction unit 102 (hereinafter also referred to as “correction unit 102”) reflects the vehicle speed V to the detected torque Td detected by the torque sensor 20. As shown in FIG. 3, the correction unit 102 includes a vehicle speed-first gain map 120 (hereinafter also referred to as “map 120”), a first rate limit processing unit 122, and a vehicle speed reflection amplifier 124 (hereinafter referred to as “first amplifier”). 124 ”).

  FIG. 4 is a diagram illustrating an example of the content of the vehicle speed-first gain map 120 in the present embodiment. The map 120 stores the relationship between the vehicle speed V and the first gain G1, and outputs the first gain G1 according to the vehicle speed V from the vehicle speed sensor 22.

  The first gain G1 is a gain for performing weighting based on the vehicle speed V for disturbance factors (particularly inertial force). As shown in FIG. 4, the first gain G1 increases as the vehicle speed V increases while the vehicle speed V is between 0 and V1. While the vehicle speed V is between V1 and V2, the first gain G1 is constant. When the vehicle speed V exceeds V2, the first gain G1 decreases as the vehicle speed V increases. The vehicle speed V1 can be set to any value of 50 to 120 km / h, for example. The vehicle speed V2 can be set to any value of 80 to 180 km / h, for example.

  The first gain G1 is used as a gain of the detected torque Td in the first amplifier 124. For this reason, when the first gain G1 increases, the detected torque Td is output to the first subtractor 114 while remaining close to the original value.

  The absolute value of the F / B current Ifb subtracted by the second subtractor 118 increases as the detected torque Td output to the first subtractor 114 (more precisely, the second correction torque Tc2) is closer to the original value. Thus, the target motor current Imot_tar becomes small. On the other hand, the absolute value of the F / B current Ifb subtracted by the second subtractor 118 becomes smaller as the detected torque Td output to the first subtractor 114 (more precisely, the second correction torque Tc2) is smaller than the original value. The value decreases and the target motor current Imot_tar increases. Therefore, by using the first gain G1, when the vehicle speed V increases, the degree of feedback of the detected torque Td can be weakened.

  The first rate limit processing unit 122 limits the absolute value of the difference between the previous value and the current value of the first gain G1 from the map 120 and outputs the difference to the vehicle speed reflecting amplifier 124 so as not to exceed a predetermined threshold value. .

  The first amplifier 124 multiplies the detected torque Td from the torque sensor 20 by the first gain G1 from the first rate limit processing unit 122 to calculate the first correction torque Tc1 and outputs it to the steering angle reflection correction unit 104. To do.

(A2-3-2-2. Steering angle reflection correction unit 104)
The steering angle reflection correction unit 104 (hereinafter also referred to as “correction unit 104”) reflects the steering angular velocity Vθst to the first correction torque Tc1 from the vehicle speed reflection correction unit 102. The positions of the vehicle speed reflection correction unit 102 and the steering angle reflection correction unit 104 may be reversed. As shown in FIG. 3, the correction unit 104 includes a steering angular velocity calculator 130, a steering angular velocity-second gain map 132 (hereinafter also referred to as “map 132”), a second rate limit processing unit 134, and a steering angular velocity. A reflection amplifier 136.

  The steering angular velocity calculator 130 (hereinafter also referred to as “calculator 130”) calculates a steering angular velocity Vθst [° / sec] as a time differential value of the steering angle θst [°].

  FIG. 5 is a diagram showing an example of the content of the steering angular velocity-second gain map 132 in the present embodiment. The map 132 stores the relationship between the steering angular velocity Vθst and the second gain G2, and outputs the second gain G2 according to the steering angular velocity Vθst from the calculator 130.

  The second gain G2 is a gain for weighting disturbance factors (particularly inertial force) based on the steering angle θst or the steering angular velocity Vθst. As shown in FIG. 5, when the steering angular velocity Vθst is 0 to Vθ1, the second gain G2 increases as the steering angular velocity Vθst increases. When the steering angular velocity Vθst exceeds Vθ1, the second gain G2 is constant. The operation of the second gain G2 is the same as that of the first gain G1. That is, by using the second gain G2, when the steering angular velocity Vθst increases, the degree of feedback of the detected torque Td can be weakened.

  The second rate limit processing unit 134 limits the absolute value of the difference between the previous value and the current value of the second gain G2 from the map 132 and outputs the difference to the steering angular velocity reflecting amplifier 136 so as not to exceed a predetermined threshold value. To do. The rudder angular velocity reflecting amplifier 136 is configured such that the second correction torque Tc2 obtained by multiplying the second gain G2 from the second rate limit processing unit 134 by the first correction torque Tc1 from the vehicle speed reflecting correction unit 102 is the target motor current calculation unit 100. Output to the first subtractor 114.

(A2-4. Control of motor controller 84)
The motor control unit 84 (hereinafter also referred to as “control unit 84”) controls the motor 56 via the inverter 32 based on the correction control amount Ucor (target motor current Imot_tar) from the correction control amount calculation unit 82. Specifically, the control unit 84 controls the duty ratio of a switching element (not shown) of the inverter 32 so as to realize the target motor current Imot_tar. At that time, the controller 84 uses the motor current Imot detected by the current sensor 26.

[A3. Effects in this embodiment]
According to the present embodiment as described above, the motor 56 is controlled so as to cancel the twist torque Td of the output shaft 60 of the motor 56 (electric motor) (FIGS. 2 and 3). The torsion torque Td includes disturbance factors such as inertia force. Therefore, by transmitting the power of the motor 56 to the output shaft 60 or the screw shaft 52 (transmission shaft) while suppressing the torsion torque Td, the influence of disturbance factors is reduced, and the target value of the power of the motor 56 (target reference) The force Fref_tar) can be realized more reliably. As a result, it is possible to improve the vibration damping characteristics of the electromagnetic damper 12 (for example, to improve the riding comfort of the vehicle 10).

  In the configuration in which the torque sensor 20 (torque detection means) detects the twisting torque Td of the output shaft 60 of the motor 56, the motor 56 (motor rotor or the like) occupies a large percentage of the inertia of the entire electromagnetic damper 12; It is possible to easily cancel the inertia of 56.

  In the present embodiment, the ECU 34 weakens the degree of feedback of the torsion torque Td as the steering angular speed Vθst increases (FIGS. 3 and 5). In other words, the ECU 34 reduces the degree of cancellation of the twisting torque Td as the steering angular velocity Vθst increases. As a result, when the vehicle 10 travels, for example, on a curved road, the influence of the inertial force remains relatively, and the damping force of the electromagnetic damper 12 can be reduced. Therefore, it is possible to improve riding comfort and improve steering response or steering stability.

  That is, since the inertial force accompanying the operation of the damper 12 is proportional to the acceleration of the damper 12 on the spring or unsprung, the phase is advanced 90 degrees from the generation of the damping force proportional to the speed of the spring or unsprung. Yes. In this embodiment, in order to weaken the degree of feedback of the twisting torque Td as the steering angular velocity Vθst increases, the torque of the motor 56 is set to a relatively high state, the ground load is increased transiently, and the posture of the wheel is changed. It becomes possible to make it difficult. As a result, it is possible to reduce the phase lag of the lateral force generation of the wheels and to speed up the response to the steering angle θst, thereby improving the steering response or the steering stability.

  In the present embodiment, the ECU 34 weakens the degree of feedback of the torsion torque Td as the vehicle speed V increases (FIGS. 3 and 4). In other words, the ECU 34 reduces the degree of cancellation of the torsion torque Td as the vehicle speed V increases. As a result, as the vehicle speed V increases, the degree of feedback of the torsion torque Td is reduced (or the degree of cancellation is reduced), so that the stability of the vehicle 10 in the high vehicle speed region is ensured by the same action as the steering angular speed Vθst. Is possible.

  In the present embodiment, the ECU 34 corrects the target reference force Fref_tar by calculating the target reference force Fref_tar as the reference control amount Uref of the motor 56 (electric motor), and corrects the target reference force Fref_tar and the target as the corrected control amount Ucor. A correction control amount calculation unit 82 that calculates the motor current Imot_tar and a motor control unit 84 (electric motor control unit) that controls the motor 56 based on the target motor current Imot_tar are provided (FIGS. 1 and 3). The correction control amount calculation unit 82 calculates the target motor current Imot_tar by reflecting the difference ΔT1 between the twist torque Td and the torque corresponding to the target reference force Fref_tar (target reference torque Tref_tar) in the target reference force Fref_tar (FIG. 2 and FIG. 2). FIG. 3). Thereby, the disturbance factor included in the twisting torque Td can be accurately excluded.

  In the present embodiment, a magnetostrictive torque sensor is used as the torque sensor 20 (torque detection means) (FIG. 1). As a result, the twist torque Td of the output shaft 60 of the motor 56 (electric motor) can be detected with high accuracy.

B. Modifications It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that various configurations can be adopted based on the description of the present specification. For example, the following configuration can be adopted.

[B1. Applicable to]
In the above embodiment, the example in which the electromagnetic damper 12 is applied to the vehicle 10 (particularly the suspension device) has been described. However, for example, from the viewpoint of controlling the motor 56 so as to cancel the twisting torque Td, the present invention is not limited to this. For example, the electromagnetic damper 12 can be applied to other devices (for example, a manufacturing device or an elevator) that require vibration damping performance.

[B2. Electromagnetic damper 12]
(B2-1. Damper body 30)
In the above embodiment, the damper main body 30 having the configuration shown in FIG. 1 is used (FIG. 1). However, for example, from the viewpoint of controlling the motor 56 so as to cancel the twisting torque Td, the present invention is not limited to this. For example, if an actuator using the motor 56 is used, a configuration such as an electrohydraulic hybrid type, a ball screw type, a rack and pinion type, a direct type (linear motor), or the like can be applied.

(B2-1-1. First Modification)
FIG. 6 is a diagram schematically showing a part of a vehicle 10A equipped with an electromagnetic damper 12a (hereinafter also referred to as “damper 12a”) according to a first modification of the present invention. Constituent elements similar to those in the above embodiment (FIG. 1) are denoted by the same reference numerals, and detailed description thereof is omitted. In FIG. 6, the sensors 14 are not shown except for the torque sensor 20.

  The damper 12a includes a damper main body 30a, an inverter 32, and an electronic control unit 34 (ECU 34). The damper main body 30a includes the connecting portion 40, the outer tube 50, the motor 56, and the connecting mechanism 150 as wheel-side members (not shown). Further, the damper main body 30a includes the inner tube 42, the nut 44, and the connection member 152 as members on the vehicle body 58 side.

  The connection mechanism 150 connects the output shaft 60 of the motor 56 and the screw shaft 52 so as to be rotatable. The coupling mechanism 150 includes a housing 160, bearings 162 and 164, a screw shaft portion side pulley 166, an endless belt 168, a motor side pulley 170, and a bearing 172.

  The housing 160 includes a screw shaft portion side holding portion 174 and a motor side holding portion 176. The screw shaft portion side holding portion 174 fixedly supports the outer tube 50 and supports the screw shaft 52 rotatably through bearings 162 and 164. The motor side holding portion 176 supports the output shaft 60 of the motor 56 via the bearing 172 so as to be rotatable. In addition, the motor side holding portion 176 fixes and supports the side wall of the motor 56.

  The screw shaft portion side pulley 166 is fixed to the screw shaft 52. The motor-side pulley 170 is fixed to the output shaft 60 of the motor 56.

  When external vibration is input to the connecting portion 40 from the wheel side and thrust is applied to the connecting portion 40 in FIG. 6, for example, upward (in the so-called dump direction), the outer tube 50 is moved against the inner tube 42 and the nut 44. Ascending, the screw shaft 52 rotates. The rotational force of the screw shaft 52 is transmitted to the output shaft 60 of the motor 56 through the screw shaft portion side pulley 166, the endless belt 168, and the motor side pulley 170. At this time, by generating a reaction force from the motor 56 to the screw shaft 52, the vibration of the spring of the suspension device can be attenuated.

(B2-1-2. Second Modification)
FIG. 7 is a diagram schematically showing a part of a vehicle 10B equipped with an electromagnetic damper 12b (hereinafter also referred to as “damper 12b”) according to a second modification of the present invention. Constituent elements similar to those in the above embodiment (FIG. 1) are denoted by the same reference numerals, and detailed description thereof is omitted. In FIG. 7, illustration of the sensors 14 is omitted except for the torque sensor 20.

  The damper 12b includes a damper main body 30b, an inverter 32, and an electronic control unit 34 (ECU 34). The damper main body 30b includes the connecting portion 40 and the inner rod 200 (rack shaft) as wheel-side members (not shown). Further, the damper main body 30b includes an outer tube 50a, a pinion shaft 202, and a motor 56 as members on the vehicle body 58 side. A torque sensor 20 is provided on the output shaft 60 of the motor 56. The motor 56 is fixed to the housing 204. As in the relationship between FIG. 1 and FIG. 6, the wheel side member and the vehicle body 58 side member can be reversed.

  Rack teeth 212 (rack gear) are formed on the inner rod 200. In addition, a pinion 214 (pinion gear) is formed on the pinion shaft 202. A rack and pinion mechanism 210 is configured by the rack teeth 212 and the pinion 214. The pinion shaft 202 is connected to the output shaft 60 of the motor 56.

  When external vibration is input from the wheel side to the connecting portion 40, and thrust is applied to the connecting portion 40 in FIG. 7, for example, upward (in the so-called dump direction), the inner rod 200 is displaced toward the outer tube 50a, The pinion shaft 202 rotates. The rotational force of the pinion shaft 202 is transmitted to the output shaft 60 of the motor 56. At this time, by generating a reaction force from the motor 56 to the pinion shaft 202, it becomes possible to attenuate the vibration of the spring of the suspension device.

  As a basic configuration of the damper main body 30b, an existing one (for example, see FIG. 2 of JP 2009-150465 A) can be used.

(B2-1-3. Third Modification)
FIG. 8 is a diagram schematically showing a part of a vehicle 10C equipped with an electromagnetic damper 12c (hereinafter also referred to as “damper 12c”) according to a third modification of the present invention. Constituent elements similar to those in the above embodiment (FIG. 1) are denoted by the same reference numerals, and detailed description thereof is omitted. In FIG. 8, the sensors 14 are not shown except for the torque sensor 20.

  The damper 12c includes a damper body 30c, an inverter 32, and an electronic control unit 34 (ECU 34). The damper main body 30c includes a connecting portion 40a and a rotating arm 250 (hereinafter also referred to as “arm 250”) as a wheel-side member (not shown). The damper main body 30c includes a reduction gear 252 and a motor 56 as members on the vehicle body side. A torque sensor 20 is provided on the output shaft 60 of the motor 56. As in the relationship between FIG. 1 and FIG. 6, the wheel side member and the vehicle body 58 side member can be reversed.

  The connecting portion 40a is connected to the wheel by being fixed to a knuckle (not shown) of the suspension device. When external vibration is input to the connecting portion 40a from the wheel side and thrust is applied to the connecting portion 40a in FIG. 8, for example, upward (in the so-called dump direction), the arm 250 tries to rotate around the rotation axis Ax. . At this time, it is possible to attenuate the vibration of the spring of the suspension device by generating a reaction force from the motor 56 to the rotary arm 250 via the speed reducer 252.

  As the basic configuration of the damper main body 30c, an existing one (for example, see Japanese Patent Laid-Open No. 02-227314) can be used.

(B2-2. Motor 56)
In the above-described embodiment, a three-phase AC brushless motor is used as the motor 56. However, for example, from the viewpoint of controlling the motor 56 so as to cancel the twisting torque Td, the motor 56 is not limited thereto. For example, the motor 56 may be a three-phase AC brush motor. The motor 56 may be a direct current motor.

(B2-3. Torque sensor 20)
In the above embodiment, the torque sensor 20 is disposed outside the motor 56 (FIGS. 1, 6 to 8). However, for example, from the viewpoint of detecting the twisting torque Td of the rotating shaft that transmits the power of the motor 56, the present invention is not limited to this.

  FIG. 9 is a view showing a modification of the arrangement of the torque sensor 20. As shown by a broken line in FIG. 9, the torque sensor 20 may be disposed inside the motor 56. In FIG. 9, the torque sensor 20 disposed outside the motor 56 is indicated by a two-dot chain line.

  In the above embodiment, the torque sensor 20 is disposed facing the output shaft 60 of the motor 56 and detects the twisting torque Td in the output shaft 60 (rotating shaft that transmits the power of the motor 56) (FIGS. 1 and 6). To FIG. 9). However, for example, from the viewpoint of detecting the twisting torque Td of the rotating shaft that transmits the power of the motor 56, the present invention is not limited thereto.

  For example, the torque sensor 20 can detect the torsion torque Td at the screw shaft 52 (FIGS. 1 and 6), the pinion shaft 202 (FIG. 7), or the rotary arm 250 (FIG. 8). For example, in FIG. 6, you may arrange | position the torque sensor 20 in any site | part of the outer tube 50 or the screw shaft part side holding | maintenance part 174. FIG. Alternatively, when another rotating shaft is interposed between the output shaft 60 of the motor 56 and the screw shaft 52, the torsion torque Td in the other rotating shaft is used as the torsion torque Td of the output shaft 60 or the screw shaft 52. Is also possible.

(B2-4.ECU 34)
(B2-4-1. Correction Control Amount Calculation Unit 82)
In the embodiment described above, the correction control amount calculation unit 82 has both the vehicle speed reflection correction unit 102 and the steering angle reflection correction unit 104 (FIG. 3). However, for example, from the viewpoint of controlling the motor 56 so as to cancel the twisting torque Td, the present invention is not limited to this. For example, the correction control amount calculation unit 82 may include only one of the vehicle speed reflection correction unit 102 and the steering angle reflection correction unit 104. Alternatively, the correction control amount calculation unit 82 may not include both the vehicle speed reflection correction unit 102 and the steering angle reflection correction unit 104.

  In the above embodiment, the steering angle reflection correction unit 104 adjusts the second gain G2 based on the steering angular velocity Vθst (FIGS. 3 and 5). However, for example, from the viewpoint of adjusting the twisting torque Td according to the lateral acceleration of the vehicle 10, the present invention is not limited to this. For example, the steering angle θst itself may be associated with the second gain G2 instead of the steering angular velocity Vθst. That is, the second gain G2 may be increased as the steering angle θst (absolute value) increases. Alternatively, the steering angle reflection correction unit 104 can increase the second gain G2 as the lateral acceleration (absolute value) detected by a lateral acceleration sensor (not shown) increases.

  In the above embodiment, the second subtractor 118 of the correction control amount calculation unit 82 calculates the difference between the target reference current Iref_tar and the F / B current Ifb as the target motor current Imot_tar (FIG. 3). In other words, the correction control amount calculation unit 82 reflects the difference ΔT1 between the torque corresponding to the reference control amount Uref and the twisting torque Td in the reference control amount Uref with the current value [A] of the motor 56 as a unit. However, for example, from the viewpoint of reflecting the difference between the torque corresponding to the reference control amount Uref and the twisting torque Td in the reference control amount Uref, the present invention is not limited to this, and other units (for example, torque [Nm] or force [ It is also possible to perform calculations using N]).

(B2-4-2. Others)
In the above embodiment, the ECU 34 is assumed to be configured by a digital circuit (FIG. 1), but a part or all of the ECU 34 may be configured by an analog circuit.

DESCRIPTION OF SYMBOLS 10, 10A, 10B, 10C ... Vehicle 12, 12a, 12b, 12c ... Electromagnetic damper 20 ... Torque sensor (torque detection means) 28 ... Steering 30, 30a, 30b, 30c ... Damper main body (motion conversion mechanism)
34 ... ECU (control device) 44 ... Nut 52 ... Screw shaft (transmission shaft) 56 ... Motor (electric motor)
60 ... Output shaft of motor 80 ... Reference control amount calculation unit 82 ... Correction control amount calculation unit 84 ... Motor control unit (electric motor control unit)
200 ... Inner rod (transmission shaft) 212 ... Rack teeth (rack gear)
214 ... Pinion (pinion gear) 250 ... Rotating arm (transmission shaft)
Fref_tar ... target reference force Imot_tar ... target motor current Td ... torsion torque Ucor ... correction control amount Uref ... reference control amount V ... vehicle speed V.theta.st ... steer angular velocity .theta.st ... steer angle .DELTA.T1 ... difference

Claims (7)

An electromagnetic damper that inputs external vibration to an output shaft of an electric motor and generates a damping force against the external vibration in the electric motor,
Torque detecting means for detecting torsion torque of a transmission shaft for transmitting the output shaft of the motor or the external vibration to the motor;
A control device for controlling the electric motor;
With
The control device controls the electric motor to cancel the torsional torque detected by the torque detection means;
Furthermore, the control device comprises:
A reference control amount calculation unit for calculating a reference control amount of the electric motor;
A correction control amount calculation unit for correcting the reference control amount to calculate a correction control amount;
An electric motor control unit for controlling the electric motor based on the correction control amount,
The electromagnetic damper is characterized in that the correction control amount calculation unit calculates the correction control amount by reflecting a difference between the twisting torque and a torque corresponding to the reference control amount in the reference control amount. The electromagnetic damper according to claim 1,
The electromagnetic damper includes a screw shaft as the transmission shaft and a nut screwed with the screw shaft,
An electromagnetic damper, wherein the linear motion of the nut relative to the screw shaft is converted into a rotational motion of the screw shaft, and the rotational motion of the screw shaft is transmitted to the output shaft of the electric motor. The electromagnetic damper according to claim 1,
The electromagnetic damper includes a rack gear formed on the transmission shaft side, and a pinion gear formed on the output shaft side of the electric motor,
The electromagnetic damper, wherein the linear motion of the transmission shaft is converted into rotational motion by the rack gear and the pinion gear, and the rotational motion of the pinion gear is transmitted to the output shaft of the electric motor. An electromagnetic damper that inputs external vibration to an output shaft of an electric motor and generates a damping force against the external vibration in the electric motor,
Torque detecting means for detecting torsion torque of a transmission shaft for transmitting the output shaft of the motor or the external vibration to the motor;
A control device for controlling the electric motor;
A rotating arm that rotates about the output shaft of the electric motor,
The control device controls the electric motor to cancel the torsional torque detected by the torque detection means;
The electromagnetic damper, wherein the torque detection means detects the torsional torque of the output shaft of the electric motor or the rotary arm. An electromagnetic damper that inputs external vibration to an output shaft of an electric motor and generates a damping force against the external vibration in the electric motor,
Torque detecting means for detecting torsion torque of a transmission shaft for transmitting the output shaft of the motor or the external vibration to the motor;
A control device for controlling the electric motor;
With
The electromagnetic damper is provided in a vehicle suspension device,
The controller is
Controlling the electric motor so as to cancel the twisting torque detected by the torque detecting means;
An electromagnetic damper, wherein the degree of cancellation of the twisting torque is reduced in accordance with an increase in steering angle or steering angular speed. An electromagnetic damper that inputs external vibration to an output shaft of an electric motor and generates a damping force against the external vibration in the electric motor,
Torque detecting means for detecting torsion torque of a transmission shaft for transmitting the output shaft of the motor or the external vibration to the motor;
A control device for controlling the electric motor;
With
The electromagnetic damper is provided in a vehicle suspension device,
The controller is
Controlling the electric motor so as to cancel the twisting torque detected by the torque detecting means;
The electromagnetic damper according to claim 1, wherein the degree of cancellation of the twisting torque is reduced according to an increase in a vehicle speed of the vehicle. In the electromagnetic damper according to any one of claims 1 to 6 ,
The electromagnetic damper is characterized in that the torque detection means is a magnetostrictive torque sensor.

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