JP4984918B2 - Electric power steering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric power steering device which realizes the recovery from fatigue of arms of a driver besides assisting the steering of a steering wheel. <P>SOLUTION: The electric power steering device 1 comprises a torque sensor 2, a vehicle speed sensor 3, a massage request switch 4, a steering angle sensor 5, a motor 6 and a control device 8. The control device 8 controls the motor 6 so as to generate torque for assisting the steering of a steering wheel based on outputs of the torque sensor 2 and vehicle speed sensor 3. In this way, the steering of the steering wheel can be assisted. The control device 8 also controls the motor 6 so as to generate torque for swinging a steering wheel based on outputs of the massage request switch 4, vehicle speed sensor 3, torque sensor 2 and steering angle sensor 5. As a result, the recovery from fatigue of a driver's arms can be realized through the swing of the steering wheel. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to an electric power steering apparatus that assists steering of a steering wheel.

  Conventionally, as an electric power steering device for assisting steering of a steering wheel, for example, there are electric power steering devices disclosed in Japanese Patent Application Laid-Open Nos. 2005-225411 and 2006-280167.

  The electric power steering device disclosed in Japanese Patent Laid-Open No. 2005-225411 includes a motor, a torque sensor, a vehicle speed sensor, a steering angle sensor, a current sensor, a rotation angle sensor, and a steering control unit. Yes. The steering control unit controls the motor to assist the operation of the steering wheel based on the outputs of these sensors.

Moreover, the electric power steering apparatus disclosed in Japanese Patent Laid-Open No. 2006-280167 includes a motor, a torque sensor, a vehicle speed sensor, and a controller. The controller controls the motor to generate steering assist torque based on the outputs of the torque sensor and the vehicle speed sensor.
JP 2005-225411 A JP 2006-280167 A

  However, the electric power steering device described above is intended to reduce the load during steering, and does not attempt to recover the driver's arm fatigue accompanying steering.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an electric power steering apparatus that assists steering of the steering wheel and can recover the fatigue of the driver's arm.

Means for Solving the Problems and Effects of the Invention

  Therefore, as a result of intensive research and trial and error to solve this problem, the present inventor has recovered the fatigue of the driver's arm by swinging the steering wheel when a massage is requested from the outside. I came up with the idea that I could plan, and came to complete the present invention.

  That is, the electric power steering apparatus according to claim 1 is an electric power steering apparatus including a motor that generates torque for assisting steering of a steering wheel, and a control unit that controls the torque of the motor. Is characterized by controlling the motor so as to generate torque for swinging the steering wheel when a massage is requested from the outside.

  According to this configuration, steering of the steering wheel can be assisted. Further, when there is a request for massage, the driver's arm can be recovered from fatigue by swinging the steering wheel.

  The electric power steering device according to claim 2 is the electric power steering device according to claim 1, and further includes a steering torque detecting means for detecting the steering torque of the steering wheel, and a vehicle speed detecting means for detecting the speed of the vehicle. And a massage request detecting means for detecting a massage request, and the control means generates torque for assisting steering of the steering wheel based on the detection results of the steering torque detecting means and the vehicle speed detecting means. The motor is controlled, and the motor is controlled to generate torque for swinging the steering wheel based on the detection results of the massage request detection means and the vehicle speed detection means.

  According to this configuration, by controlling the motor based on the detection result of the steering torque detection means, it is possible to generate sufficient torque that assists the steering of the steering wheel. In addition, by controlling based on the detection result of the vehicle speed detection means, it is possible to generate a torque according to the speed of the vehicle, thus ensuring safety. Further, by controlling the motor based on the detection result of the massage request detection means, the steering wheel can be swung according to the massage request. In addition, by controlling based on the detection result of the vehicle speed detecting means, the vehicle can be swung according to the speed of the vehicle, so that safety can be ensured.

  The electric power steering device according to claim 3 is the electric power steering device according to claim 2, and further, the control means detects the massage request by the massage request detection means, and the detection result of the vehicle speed detection means. The motor is controlled so as to generate torque for swinging the steering wheel when is less than a predetermined speed.

  According to this configuration, the steering wheel can be reliably swung in response to a massage request. In addition, since the vehicle is swung when the vehicle speed is equal to or lower than a predetermined speed, sufficient safety can be ensured.

  According to a fourth aspect of the present invention, there is provided the electric power steering apparatus according to the first aspect, further comprising a steering torque detecting means for detecting a steering torque of the steering wheel, and a vehicle speed detecting means for detecting the speed of the vehicle. And a massage request detecting means for detecting a massage request, and the control means generates torque for assisting steering of the steering wheel based on the detection results of the steering torque detecting means and the vehicle speed detecting means. The motor is controlled, and the motor is controlled so as to generate torque for swinging the steering wheel based on detection results of the massage request detection means, the vehicle speed detection means, and the steering torque detection means.

  According to this configuration, by controlling the motor based on the detection result of the steering torque detection means, it is possible to generate sufficient torque that assists the steering of the steering wheel. In addition, by controlling based on the detection result of the vehicle speed detection means, it is possible to generate a torque according to the speed of the vehicle, thus ensuring safety. Further, by controlling the motor based on the detection result of the massage request detection means, the steering wheel can be swung according to the massage request. Moreover, by controlling based on the detection results of the vehicle speed detection means and the steering torque detection means, the steering wheel can be swung according to the vehicle speed and the steering torque. Therefore, safety can be ensured and the influence on the behavior of the vehicle can be suppressed.

  The electric power steering device according to claim 5 is the electric power steering device according to claim 4, and further, the control means detects the massage request by the massage request detection means, and the detection result of the vehicle speed detection means. Is less than a predetermined speed, and when the detection result of the steering torque detecting means is less than the predetermined torque, the motor is controlled so as to generate torque for swinging the steering wheel.

  According to this configuration, the steering wheel can be reliably swung in response to a massage request. In addition, since the vehicle is swung when the vehicle speed is equal to or lower than a predetermined speed, sufficient safety can be ensured. Further, since the rocking is performed when the steering torque is equal to or less than the predetermined torque, the influence on the behavior of the vehicle can be surely suppressed.

  The electric power steering device according to claim 6 is the electric power steering device according to claim 1, and further includes a steering torque detecting means for detecting the steering torque of the steering wheel, and a vehicle speed detecting means for detecting the speed of the vehicle. The massage request detecting means for detecting the massage request and the steering angle detecting means for detecting the steering angle of the steering wheel, the control means for steering based on the detection results of the steering torque detecting means and the vehicle speed detecting means. The motor is controlled to generate torque for assisting the steering of the wheel, and the torque for swinging the steering wheel is determined based on the detection results of the massage request detecting means, the vehicle speed detecting means, and the steering angle detecting means. The motor is controlled so as to be generated.

  According to this configuration, by controlling the motor based on the detection result of the steering torque detection means, it is possible to generate sufficient torque that assists the steering of the steering wheel. In addition, by controlling based on the detection result of the vehicle speed detection means, it is possible to generate a torque according to the speed of the vehicle, thus ensuring safety. Further, by controlling the motor based on the detection result of the massage request detection means, the steering wheel can be swung according to the massage request. Moreover, since the steering wheel can be swung according to the speed of the vehicle by controlling based on the detection result of the vehicle speed detecting means, safety can be ensured. By performing the control based on the detection result of the steering angle detection means, it is possible to prevent a collision between the constituent members accompanying the swinging of the steering wheel.

  The electric power steering device according to claim 7 is the electric power steering device according to claim 6, and further, the control means detects the massage request by the massage request detection means, and the detection result of the vehicle speed detection means. Is less than a predetermined speed and the detection result of the steering angle detection means is within a predetermined angle range, the motor is controlled to generate torque for swinging the steering wheel.

  According to this configuration, the steering wheel can be reliably swung in response to a massage request. In addition, since the vehicle is swung when the vehicle speed is equal to or lower than a predetermined speed, sufficient safety can be ensured. Further, since the rocking is performed when the steering angle is within the predetermined angle range, the collision between the constituent members can be reliably suppressed.

  An electric power steering apparatus according to an eighth aspect of the present invention is the electric power steering apparatus according to the first aspect, further comprising a steering torque detecting means for detecting the steering torque of the steering wheel, and a vehicle speed detecting means for detecting the speed of the vehicle. The massage request detecting means for detecting the massage request and the steering angle detecting means for detecting the steering angle of the steering wheel, the control means for steering based on the detection results of the steering torque detecting means and the vehicle speed detecting means. The motor is controlled to generate torque for assisting the steering of the wheel, and the steering wheel is swung based on the detection results of the massage request detection means, the vehicle speed detection means, the steering torque detection means, and the steering angle detection means. The motor is controlled so as to generate torque for That.

  According to this configuration, by controlling the motor based on the detection result of the steering torque detection means, it is possible to generate sufficient torque that assists the steering of the steering wheel. In addition, by controlling based on the detection result of the vehicle speed detection means, it is possible to generate a torque according to the speed of the vehicle, thus ensuring safety. Further, by controlling the motor based on the detection result of the massage request detection means, the steering wheel can be swung according to the massage request. Moreover, by controlling based on the detection results of the vehicle speed detection means and the steering torque detection means, the steering wheel can be swung according to the vehicle speed and the steering torque. Therefore, safety can be ensured and the influence on the behavior of the vehicle can be suppressed. Further, by performing control based on the detection result of the steering angle detection means, it is possible to prevent the collision between the constituent members accompanying the swinging of the steering wheel.

  The electric power steering apparatus according to claim 9 is the electric power steering apparatus according to claim 8, wherein the control means detects the massage request by the massage request detection means, and the detection result of the vehicle speed detection means. So that the torque for swinging the steering wheel is generated when the detection result of the steering torque detection means is less than the predetermined torque and the detection result of the steering angle detection means is within the predetermined angle range. The motor is controlled.

  According to this configuration, the steering wheel can be reliably swung in response to a massage request. In addition, since the vehicle is swung when the vehicle speed is equal to or lower than a predetermined speed, sufficient safety can be ensured. Further, since the rocking is performed when the steering torque is equal to or less than the predetermined torque, the influence on the behavior of the vehicle can be surely suppressed. Furthermore, since the rocking is performed when the steering angle is within the predetermined angle range, the collision between the constituent members can be reliably suppressed.

  The electric power steering device according to a tenth aspect is the electric power steering device according to any one of the fourth, fifth, eighth, and ninth aspects, and the control means further includes a detection result of the steering torque detecting means that is a predetermined torque. If it exceeds, the motor is controlled so as not to generate torque for swinging the steering wheel thereafter.

  According to this configuration, the swinging can be stopped without releasing the hand from the steering wheel. Therefore, usability can be improved.

  Next, an embodiment is given and this invention is demonstrated in detail.

(First embodiment)
First, the configuration of the electric power steering apparatus will be described with reference to FIGS. Here, FIG. 1 is a configuration diagram of the electric power steering apparatus in the present embodiment. FIG. 2 is a block diagram of the electric power steering apparatus. FIG. 3 is a graph showing a massage current command.

  As shown in FIG. 1, an electric power steering apparatus 1 includes a torque sensor 2 (steering torque detection means), a vehicle speed sensor 3 (vehicle speed detection means), a massage request switch 4 (massage request detection means), and a steering angle sensor. 5 (steering angle detection means), a motor 6, a speed reduction device 7, and a control device 8 (control means). The steering wheel 9 is fixed to one end portion of the steering shaft 10. A pinion gear (not shown) is formed at the other end of the steering shaft 10. The pinion gear meshes with a rack 12 accommodated in the steering gear box 11. Wheels 16 fitted with tires 15 are fixed to both ends of the rack 12 via tie rods 13 and knuckle arms 14.

  The torque sensor 2 is a sensor that detects the steering torque of the steering wheel 9. The torque sensor 2 is installed on the steering shaft 10. The vehicle speed sensor 3 is a sensor that detects the speed of the vehicle. The vehicle speed sensor 3 is installed in the vicinity of the wheel 16. The massage request switch 4 is a switch for requesting the execution of massage. The massage request switch 4 is installed on the instrument panel. The massage request switch 4 may be provided on the monitor screen of the navigation system as a touch panel switch. The steering angle sensor 5 is a sensor that detects the steering angle of the steering wheel 9. The steering angle sensor 5 is installed on the steering shaft 10 closer to the steering wheel 9 than the torque sensor 2. The steering angle sensor 5 may be substituted by a rotation angle sensor when the motor 6 described later includes a rotation angle sensor.

The motor 6 is a device that generates torque for assisting the steering of the steering wheel 9 and generates torque for swinging the steering wheel 9 when a predetermined condition is satisfied. The reduction gear 7 is a device that reduces the rotation of the motor 6 and transmits the generated torque to the steering shaft 10. The motor 6 is meshed with the steering shaft 10 via a reduction gear 7 installed on the side opposite to the steering wheel 9 than the torque sensor 2. The control device 8 includes a torque sensor 2, a vehicle speed sensor 3, and a massage request switch 4. And a device for controlling the motor 6 based on the output of the steering angle sensor 5. The control device 8 controls the motor 6 so as to generate torque for assisting steering of the steering wheel 9 based on the outputs of the torque sensor 2 and the vehicle speed sensor 3. Further, based on the outputs of the massage request switch 4, the vehicle speed sensor 3, the torque sensor 2 and the steering angle sensor 5, the motor 6 is controlled so as to generate torque for swinging the steering wheel 9. As shown in FIG. 2, the control device 8 includes a steering assist current command calculation unit 8a, a massage permission determination unit 8b, a massage current command calculation unit 8c, a current command adjustment unit 8d, and a current control unit 8e. It is composed of The steering assist current command calculation unit 8a, the massage permission determination unit 8b, the massage current command calculation unit 8c, and the current command adjustment unit 8d are configured by a program on a microcomputer. The current control unit 8e is configured by a plurality of switch elements (not shown).

  The steering assist current command calculation unit 8 a is a block that calculates and outputs a steering assist current command corresponding to the torque for assisting the steering of the steering wheel 9 based on the outputs of the torque sensor 2 and the vehicle speed sensor 3. .

  The massage permission determination unit 8 b is a block that determines whether or not to permit the massage based on the outputs of the torque sensor 2, the vehicle speed sensor 3, the massage request switch 4, and the steering angle sensor 5. The massage permission determination unit 8b is configured such that the massage request switch 4 is turned on, massage is requested, the output of the vehicle speed sensor 3 is a low speed equal to or lower than a predetermined speed, and the output of the torque sensor 2 is equal to or lower than a predetermined torque. Yes, and when the output of the steering angle sensor 5 is within a predetermined angle range, the massage permission flag for permitting the massage is validated. Here, the predetermined speed and the predetermined torque are set to a speed and torque that do not adversely affect the behavior of the vehicle even if the steering wheel 9 is swung. The predetermined angle range is set to an angle range in which the rack 12 does not reach the movement limit even when the steering wheel 9 is swung.

  The massage current command calculation unit 8c is a block that calculates and outputs a massage current command corresponding to the torque for swinging the steering wheel 9 based on the output of the massage permission determination unit 8b. When the massage permission flag is enabled, the massage current command calculation unit 8c calculates and outputs a massage current command having a constant amplitude and a constant frequency as shown in FIG. Here, the amplitude of the massage current command is set to a size that does not adversely affect the behavior of the vehicle. The amplitude of the massage current command may be set to a size that does not cause abnormal wear of the tire 15. Further, the massage current command may vary the amplitude over time. The frequency may be varied with time. Further, the amplitude and frequency may be varied with time.

  As shown in FIG. 2, the current command adjustment unit 8 d is a block that adjusts the outputs of the steering assist current command calculation unit 8 a and the massage current command calculation unit 8 c and outputs the final current command. The current command adjusting unit 8d adds the massage current command to the steering assist current command to obtain a final current command. Further, it is converted into a PWM signal corresponding to this current command and output. The current command adjusting unit 8d selectively selects the steering assist current command when the massage permission flag is invalid and the massage current signal as the final current command when the massage permission signal is valid. It may be output.

  The current control unit 8e is a block that controls the current flowing through the motor 6 based on the output of the current command adjustment unit 8d. The current control unit 8e controls the voltage applied to the motor 6 so that the current flowing through the motor 6 matches the current command.

  Next, the operation of the electric power steering apparatus will be described with reference to FIGS. First, the operation of the massage permission determination unit will be described with reference to FIG. Here, FIG. 4 is a flowchart for explaining the operation of the massage permission determination unit.

  As illustrated in FIG. 4, the massage permission determination unit 8b disables the massage permission flag when the operation starts (S100). Thereafter, the output of the massage request switch 4 is read (S101). Then, the massage request switch 4 is turned on, and it is determined whether or not massage is requested (S102).

  If the massage request switch 4 is off in step S102, the process returns to step S100. On the other hand, in step S102, when the massage request switch 4 is on, the massage permission determination unit 8b reads the output of the vehicle speed sensor 3 (S103). Then, it is determined whether or not the output of the vehicle speed sensor 3 is equal to or lower than the predetermined speed and the vehicle speed is low (S104).

  In step S104, when the output of the vehicle speed sensor 3 exceeds the predetermined speed, the process returns to step S100. On the other hand, when the output of the vehicle speed sensor 3 is equal to or lower than the predetermined speed in step S104, the massage permission determination unit 8b reads the output of the torque sensor 2 (S105). And it is determined whether the output of the torque sensor 2 is below a predetermined torque (S106).

  In step S106, when the output of the torque sensor 2 exceeds the predetermined torque, the process returns to step S100. On the other hand, when the output of the torque sensor 2 is equal to or lower than the predetermined torque in step S106, the massage permission determination unit 8b reads the output of the steering angle sensor 5 (S107). Then, it is determined whether or not the output of the steering angle sensor 5 is within a predetermined angle range (S108).

  If the output of the steering angle sensor 5 is outside the predetermined angle range in step S108, the process returns to step S100. On the other hand, in step S108, when the output of the steering angle sensor 5 is within the predetermined angle range, the massage permission determination unit 8b enables the massage permission flag (S109). Thereafter, the process returns to step 101 and the same steps are repeated.

  Next, the operation of the electric power steering device will be described. Here, FIG. 5 is a time chart for explaining the operation of the electric power steering apparatus.

  In FIG. 1, when the steering wheel 9 is steered, the steering assist current command calculation unit 8 a shown in FIG. 2 assists steering of the steering wheel 9 based on the outputs of the torque sensor 2 and the vehicle speed sensor 3. The steering assist current command corresponding to the torque is calculated and output. When the massage request switch 4 is off, as shown in FIG. 5, the massage permission determination unit 8b invalidates the massage permission flag. Therefore, in FIG. 2, the massage current command calculation unit 8 c does not output a massage current command. Therefore, the current command adjusting unit 8d outputs the steering assist current command as it is. The steering assist current command is input to the current control unit 8e as a final current command. The current control unit 8e controls the voltage applied to the motor 6 so that the current flowing through the motor 6 matches the steering assist current command. As a result, steering of the steering wheel is appropriately assisted and the load during steering is reduced.

  On the other hand, when the massage request switch 4 is turned on, as described in FIG. 4, the massage permission determination unit 8 b determines whether or not the output of the vehicle sensor 3 is equal to or lower than a predetermined speed. Further, it is determined whether or not the output of the torque sensor 2 is equal to or less than a predetermined torque. Further, it is determined whether or not the output of the steering angle sensor 5 is within a predetermined angle range. When it is determined that the output of the vehicle speed sensor 3 is equal to or lower than the predetermined speed, the output of the torque sensor 2 is equal to or lower than the predetermined torque, and the output of the steering angle sensor 5 is within the predetermined angle range, as shown in FIG. The massage permission determination unit 8b enables the massage permission flag (t0). When the massage permission flag becomes valid, the massage current command calculation unit 8c calculates and outputs a massage current command. The current command adjusting unit 8d adds the massage current command to the steering assist current command, and outputs the result as a final current command. The current control unit 8e controls the voltage applied to the motor 6 so that the current flowing through the motor 6 matches the current command. As a result, steering of the steering wheel 9 is appropriately assisted, the load during steering is reduced, and the steering wheel 9 is swung to recover the fatigue of the driver's arm.

  Thereafter, when the steering wheel 9 is steered and the output of the torque sensor 2 exceeds a predetermined torque, the massage permission determination unit 8b invalidates the massage permission flag (t1). Therefore, the massage current command calculation unit 8c stops outputting the massage current command. Therefore, the current command adjusting unit 8d outputs the steering assist current command as it is. As a result, the swing of the steering wheel 9 is stopped, and only steering assistance is performed.

  Thereafter, when the steering of the steering wheel 9 is finished and the output of the torque sensor 2 becomes equal to or lower than the predetermined torque, the massage permission determination unit 8b enables the massage permission flag (t2). Therefore, the massage current command calculation unit 8c outputs a massage current command. Thereby, the swinging of the steering wheel 9 is resumed.

  When the massage is not necessary and the massage request switch 4 is turned off, the massage permission determination unit 8b invalidates the massage permission flag (t3). Thereby, the swinging of the steering wheel 9 is stopped, and the massage is finished.

  Finally, the effect will be described. According to the first embodiment, by controlling the motor 6 based on the output of the torque sensor 2, it is possible to generate sufficient torque that assists the steering wheel 9. Thereby, steering of the steering wheel 9 can be assisted. Moreover, since the torque according to the speed of the vehicle can be generated by controlling based on the output of the vehicle speed sensor 3, safety can be ensured. Further, by controlling the motor 6 based on the output of the massage request switch 4, the steering wheel 9 can be swung in response to a massage request. As a result, the fatigue of the driver's arm can be recovered. In addition, since the vehicle is swung when the vehicle speed is equal to or lower than a predetermined speed, safety can be ensured. Further, since the rocking is performed when the steering torque is equal to or less than the predetermined torque, the influence on the behavior of the vehicle can be suppressed. Furthermore, since the rocking is performed when the steering angle is within a predetermined angle range, the collision of the rack 12 with other components can be suppressed.

(Second Embodiment)
Next, an electric power steering apparatus according to a second embodiment will be described. The electric power steering device of the second embodiment is obtained by changing the massage permission determination unit with respect to the electric power steering device of the first embodiment.

  First, the configuration of the electric power steering apparatus will be described with reference to FIG. Here, FIG. 6 is a block diagram of the electric power steering apparatus in the second embodiment. Here, only the massage permission determination part which is a different part from the electric power steering apparatus of 1st Embodiment is demonstrated, and description except a required part is abbreviate | omitted about a common part. In addition, the same code | symbol is attached | subjected and demonstrated to the element same as embodiment mentioned above.

  As shown in FIG. 6, the electric power steering device 17 includes a torque sensor 2 (steering torque detecting means), a vehicle speed sensor 3 (vehicle speed detecting means), a massage request switch 4 (massage request detecting means), and a steering angle sensor. 5 (steering angle detection means), a motor 6, and a control device 18 (control means). The control device 18 includes a steering assist current command calculation unit 18a, a massage permission determination unit 18b, a massage current command calculation unit 18c, a current command adjustment unit 18d, and a current control unit 18e. The steering assist current command calculation unit 18a, the massage current command calculation unit 18c, the current command adjustment unit 18d, and the current control unit 18e are the steering assist current command calculation unit 8a and the massage current in the first embodiment. Since the command calculation unit 8c, the current command adjustment unit 8d, and the current control unit 8e are the same, the description thereof is omitted.

  The massage permission determination unit 18 b is a block that determines whether or not to permit the massage based on the outputs of the vehicle speed sensor 3, the massage request switch 4, and the steering angle sensor 5. The massage permission determination unit 18b is configured such that the massage request switch 4 is turned on, massage is requested, the output of the vehicle speed sensor 3 is a low speed equal to or lower than a predetermined speed, and the output of the steering angle sensor 5 is within a predetermined angle range. If it is within, enable the massage permission flag that allows the massage to be performed. Here, the predetermined speed is set to a speed that does not adversely affect the behavior of the vehicle even if the steering wheel 9 is swung. The predetermined angle range is set to an angle range in which the rack 12 does not reach the movement limit even when the steering wheel 9 is swung.

  The operation of the electric power steering device 17 is the same as the operation of the electric power steering device 1 of the first embodiment except that the conditions for enabling the massage permission flag are different. Therefore, explanation is omitted.

Finally, the effect will be described. According to the second embodiment, as in the first embodiment, safety can be ensured and steering of the steering wheel 9 can be assisted. Further, by swinging the steering wheel 9, it is possible to recover the driver's arm fatigue. In addition, since the vehicle is swung when the vehicle speed is equal to or lower than a predetermined speed, safety can be ensured. Further, since the swinging is performed when the steering angle is within the predetermined angle range, the rack 12 can be prevented from colliding with other components (third embodiment).
Next, an electric power steering apparatus according to a third embodiment will be described. The electric power steering apparatus according to the third embodiment is obtained by eliminating the steering angle sensor and changing the massage permission determination unit with respect to the electric power steering apparatus according to the first embodiment.

  First, the configuration of the electric power steering apparatus will be described with reference to FIG. Here, FIG. 7 is a block diagram of the electric power steering apparatus in the third embodiment. Here, only the massage permission determination part which is a different part from the electric power steering apparatus of 1st Embodiment is demonstrated, and description except a required part is abbreviate | omitted about a common part. In addition, the same code | symbol is attached | subjected and demonstrated to the element same as embodiment mentioned above.

  As shown in FIG. 7, the electric power steering device 19 includes a torque sensor 2 (steering torque detection means), a vehicle speed sensor 3 (vehicle speed detection means), a massage request switch 4 (massage request detection means), a motor 6, And a control device 20 (control means). The control device 20 includes a steering assist current command calculation unit 20a, a massage permission determination unit 20b, a massage current command calculation unit 20c, a current command adjustment unit 20d, and a current control unit 20e. The steering assist current command calculation unit 20a, the massage current command calculation unit 20c, the current command adjustment unit 20d, and the current control unit 20e are the steering assist current command calculation unit 8a and the massage current in the first embodiment. Since the command calculation unit 8c, the current command adjustment unit 8d, and the current control unit 8e are the same, the description thereof is omitted.

  The massage permission determination unit 20 b is a block that determines whether or not to permit the massage based on the outputs of the torque sensor 2, the vehicle speed sensor 3, and the massage request switch 4. The massage permission determination unit 20b is configured such that the massage request switch 4 is turned on, massage is requested, the output of the vehicle speed sensor 3 is a low speed equal to or lower than a predetermined speed, and the output of the torque sensor 2 is equal to or lower than a predetermined torque. At some point, the massage permission flag that permits the massage is enabled. Here, the predetermined speed and the predetermined torque are set to a speed and torque that do not adversely affect the behavior of the vehicle even if the steering wheel 9 is swung.

  The operation of the electric power steering device 19 is the same as the operation of the electric power steering device 1 of the first embodiment except that the conditions for enabling the massage permission flag are different. Therefore, explanation is omitted.

  Finally, the effect will be described. According to the third embodiment, as in the first embodiment, safety can be ensured and steering of the steering wheel 9 can be assisted. Further, by swinging the steering wheel 9, it is possible to recover the driver's arm fatigue. In addition, since the vehicle is swung when the vehicle speed is equal to or lower than a predetermined speed, safety can be ensured. Further, since the rocking is performed when the steering torque is equal to or less than the predetermined torque, the influence on the behavior of the vehicle can be suppressed.

(Fourth embodiment)
Next, an electric power steering apparatus according to a fourth embodiment will be described. The electric power steering apparatus according to the fourth embodiment is obtained by eliminating the steering angle sensor and changing the massage permission determination unit with respect to the electric power steering apparatus according to the first embodiment.

  First, the configuration of the electric power steering apparatus will be described with reference to FIG. Here, FIG. 8 is a block diagram of the electric power steering apparatus in the fourth embodiment. Here, only the massage permission determination part which is a different part from the electric power steering apparatus of 1st Embodiment is demonstrated, and description except a required part is abbreviate | omitted about a common part. In addition, the same code | symbol is attached | subjected and demonstrated to the element same as embodiment mentioned above.

  As shown in FIG. 8, the electric power steering device 21 includes a torque sensor 2 (steering torque detecting means), a vehicle speed sensor 3 (vehicle speed detecting means), a massage request switch 4 (massage request detecting means), a motor 6, And a control device 22 (control means). The control device 22 includes a steering assist current command calculation unit 22a, a massage permission determination unit 22b, a massage current command calculation unit 22c, a current command adjustment unit 22d, and a current control unit 22e. The steering assist current command calculation unit 22a, the massage current command calculation unit 22c, the current command adjustment unit 22d, and the current control unit 22e are the steering assist current command calculation unit 8a and the massage current in the first embodiment. Since the command calculation unit 8c, the current command adjustment unit 8d, and the current control unit 8e are the same, the description thereof is omitted.

  The massage permission determination unit 22 b is a block that determines whether or not to permit the massage based on the outputs of the vehicle speed sensor 3 and the massage request switch 4. The massage permission determination unit 22b activates the massage permission flag that permits the massage to be performed when the massage request switch 4 is turned on, the massage is requested, and the output of the vehicle speed sensor 3 is a low speed equal to or lower than a predetermined speed. To. Here, the predetermined speed is set to a speed that does not adversely affect the behavior of the vehicle even if the steering wheel 9 is swung.

  The operation of the electric power steering device 21 is the same as the operation of the electric power steering device 1 of the first embodiment except that the conditions for enabling the massage permission flag are different. Therefore, explanation is omitted.

  Finally, the effect will be described. According to the fourth embodiment, as in the first embodiment, safety can be ensured and steering of the steering wheel 9 can be assisted. Further, by swinging the steering wheel 9, it is possible to recover the driver's arm fatigue. In addition, since the vehicle is swung when the vehicle speed is equal to or lower than a predetermined speed, safety can be ensured.

  In the first embodiment, as shown in FIG. 5, when the output of the torque sensor 2 returns below the predetermined torque after exceeding the predetermined torque, an example is given in which the massage permission flag is re-enabled. However, it is not limited to this. For example, as shown in FIG. 9, when a predetermined torque is exceeded, the massage permission flag may be invalidated thereafter. Thereby, a massage can be complete | finished by steering of the steering wheel 9, and usability can be improved. The same applies to the third embodiment.

It is a lineblock diagram of the electric power steering device in a 1st embodiment. It is a block diagram of an electric power steering device. It is a graph which shows the electric current command for massage. It is a flowchart for demonstrating operation | movement of an electric power steering apparatus. It is a time chart for demonstrating operation | movement of an electric power steering apparatus. It is a block diagram of the electric power steering device in a 2nd embodiment. It is a block diagram of the electric power steering device in a 3rd embodiment. It is a block diagram of the electric power steering device in a 4th embodiment. It is a time chart for demonstrating operation | movement of the electric power steering apparatus in other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 17, 19, 21 ... Electric power steering device, 2 ... Torque sensor (steering torque detection means), 3 ... Vehicle speed sensor (vehicle speed detection means), 4 ... Massage request switch (massage request) Detection means), 5... Steering angle sensor (steering angle detection means), 6... Motor, 7... Reduction device, 8, 18, 20, 22. 18a, 20a, 22a ... steering assist current command calculation unit, 8b, 18b, 20b, 22b ... massage permission determination unit, 8c, 18c, 20c, 22c ... massage current command calculation unit, 8d, 18d, 20d, 22d ... current command adjustment unit, 8e, 18e, 20e, 22e ... current control unit, 9 ... steering wheel, 10 ... steering shaft, 11 ... steering wheel Ring gear box, 12 ... rack 13 ... tie rod, 14 ... knuckle arm 15 ... tire, 16 ... wheel

Claims (10)

An electric power steering apparatus comprising: a motor that generates torque for assisting steering of a steering wheel; and a control unit that controls torque of the motor.
The electric power steering apparatus characterized in that the control means controls the motor to generate torque for swinging the steering wheel when a massage is requested from the outside. Steering torque detection means for detecting the steering torque of the steering wheel, vehicle speed detection means for detecting the speed of the vehicle, and massage request detection means for detecting a massage request,
The control means controls the motor to generate torque for assisting steering of the steering wheel based on detection results of the steering torque detection means and the vehicle speed detection means, and the massage request detection means 2. The electric power steering apparatus according to claim 1, wherein the motor is controlled so as to generate a torque for swinging the steering wheel based on a detection result of the vehicle speed detection means.   The control means generates the torque for swinging the steering wheel when the massage request detection means detects a massage request and the detection result of the vehicle speed detection means is a predetermined speed or less. The electric power steering apparatus according to claim 2, wherein the motor is controlled. Steering torque detection means for detecting the steering torque of the steering wheel, vehicle speed detection means for detecting the speed of the vehicle, and massage request detection means for detecting a massage request,
The control means controls the motor to generate torque for assisting steering of the steering wheel based on detection results of the steering torque detection means and the vehicle speed detection means, and the massage request detection means 2. The electric motor according to claim 1, wherein the motor is controlled so as to generate a torque for swinging the steering wheel based on detection results of the vehicle speed detection means and the steering torque detection means. Power steering device.   The control means detects when the massage request detection means detects a massage request, the detection result of the vehicle speed detection means is equal to or lower than a predetermined speed, and the detection result of the steering torque detection means is equal to or lower than a predetermined torque. The electric power steering apparatus according to claim 4, wherein the motor is controlled so as to generate a torque for swinging the steering wheel. Steering torque detection means for detecting the steering torque of the steering wheel, vehicle speed detection means for detecting the speed of the vehicle, massage request detection means for detecting a massage request, and steering angle detection for detecting the steering angle of the steering wheel Means,
The control means controls the motor to generate torque for assisting steering of the steering wheel based on detection results of the steering torque detection means and the vehicle speed detection means, and the massage request detection means 2. The electric motor according to claim 1, wherein the motor is controlled so as to generate torque for swinging the steering wheel based on detection results of the vehicle speed detection means and the steering angle detection means. Power steering device.   When the massage request detection means detects a massage request, the detection result of the vehicle speed detection means is a predetermined speed or less, and the detection result of the steering angle detection means is within a predetermined angle range, The electric power steering apparatus according to claim 6, wherein the motor is controlled so as to generate torque for swinging the steering wheel. Steering torque detection means for detecting the steering torque of the steering wheel, vehicle speed detection means for detecting the speed of the vehicle, massage request detection means for detecting a massage request, and steering angle detection for detecting the steering angle of the steering wheel Means,
The control means controls the motor to generate torque for assisting steering of the steering wheel based on detection results of the steering torque detection means and the vehicle speed detection means, and the massage request detection means The motor is controlled to generate torque for swinging the steering wheel based on detection results of the vehicle speed detection means, the steering torque detection means, and the steering angle detection means. Item 4. The electric power steering device according to Item 1.   The control means detects the massage request, the massage request detection means detects a massage speed, the detection result of the vehicle speed detection means is a predetermined speed or less, and the detection result of the steering torque detection means is a predetermined torque or less. 9. The electric power steering apparatus according to claim 8, wherein when the detection result of the steering angle detection means is within a predetermined angle range, the motor is controlled to generate a torque for swinging the steering wheel. . 5. The control unit according to claim 4, wherein when the detection result of the steering torque detection unit exceeds a predetermined torque, the control unit controls the motor not to generate torque for swinging the steering wheel. The electric power steering apparatus according to any one of 5, 8, and 9.

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