JP5987352B2 - Power steering device - Google Patents

Description

  The present invention relates to a power steering device mounted on a vehicle having a vehicle control device that turns the vehicle by controlling the distribution of driving force or the distribution of brakes on the left and right wheels of the vehicle.

  2. Description of the Related Art Conventionally, power steering apparatuses for vehicles include an electric power steering apparatus (EPS) using a motor as a drive source. Usually, in such an EPS, the control device detects a steering torque transmitted through the steering shaft, and based on the steering torque, a target assist force (a basic control component) to be applied to the steering system is determined. The operation of the actuator is controlled through calculation and supply of driving power to the motor.

  By the way, in recent years, for example, there is a vehicle equipped with a vehicle control device such as a vehicle stability control device that suppresses skid during turning, and by actively changing the braking force distribution (and driving force distribution) of each wheel. The introduction of automation technology that automatically controls the driving behavior is underway. At the time of execution of the automatic control, a configuration in which the power assist control is executed so as to attract and assist the steering operation that reaches the target running state of the automatic control is also common. (For example, refer to Patent Document 1).

JP 2005-350054 A

  However, in such a power steering device, in order to prevent steering locking or the like when an abnormality occurs, if the application of assist force is stopped, the operator must steer with a large force, It is not easy to steer as intended by the driver, such as changing the steering angle and the course of the vehicle. Further, even when the various vehicle control devices described above are mounted on the vehicle, since the vehicle is turned according to the steering angle, it is not as easy to steer as intended by the driver. .

  SUMMARY OF THE INVENTION The present invention provides a power steering device capable of facilitating steering as intended by a driver in the event of an abnormality related to an actuator.

  In order to achieve the above object, the invention according to claim 1 is a power mounted on a vehicle having a vehicle control device for turning the vehicle by controlling the distribution of driving force or the distribution of brakes on the left and right wheels of the vehicle. In the steering apparatus, a torque sensor that detects a steering torque applied to the steering system by steering, an actuator that applies an assisting force to assist the steering to the steering system, and the steering torque detected by the torque sensor A control device that controls the assist force by controlling an actuator, and the control device steers on the condition that a steering torque detected by the torque sensor exceeds a threshold value when an abnormality relating to the actuator occurs. The vehicle is counted with respect to the vehicle control device according to the number of times of steering. It is to control the distribution or allocation of the braking of the driving force of the left and right wheels, and summarized in that performs control for applying an assist force for assisting the steering.

  According to the above configuration, even when the actuator is abnormal, it is possible to control the distribution of the driving force or the brake distribution on the left and right wheels of the vehicle according to the number of steerings counted on the condition that the steering torque exceeds the threshold. Assist force for assisting steering can be applied. Therefore, it is possible to facilitate the steering as intended by the driver without continuing to apply a large steering torque by steering in the event of an abnormality related to the actuator.

  According to a second aspect of the present invention, in the electric power steering device according to the first aspect, the control device indicates that the steering torque detected by the torque sensor has exceeded a threshold value when an abnormality has occurred in the actuator. The gist of the present invention is to perform control for notifying the notifying means for notifying the driver.

  According to the above configuration, it is possible to make the driver recognize that the steering torque applied to the steering system by the steering has exceeded the threshold value, and to specify that the assist force assisting the steering is applied.

  According to a third aspect of the present invention, in the electric power steering device according to the first or second aspect of the invention, the control device is configured to control the steering direction detected by the torque sensor when the abnormality is related to the actuator. The gist is to control the vehicle control device so that the assist force is applied.

According to the above configuration, it is possible to apply the assist force that assists the steering in the direction corresponding to the steering direction, and it is possible to smoothly turn the vehicle according to the driver's steering .

  ADVANTAGE OF THE INVENTION According to this invention, it can make it easy to steer as a driver | operator's intention at the time of abnormality regarding an actuator.

The schematic diagram explaining the vehicle in 1st Embodiment. The timing chart which shows the steering torque in 1st Embodiment. The timing chart which shows the steering angle in 1st Embodiment. (A)-(d) is explanatory drawing explaining the display mode of the image in 1st Embodiment. The flowchart which shows the steering control process at the time of abnormality in 1st Embodiment. The schematic diagram explaining the vehicle in 2nd Embodiment.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, an electric power steering device (EPS) 1 according to this embodiment is mounted on a vehicle C having a vehicle control device 18 that controls the distribution of driving force between left and right wheels.

  In such an EPS 1, the steering shaft 3 to which the steering 2 is fixed is connected to the rack shaft 5 via the rack and pinion mechanism 4. The rotation of the steering shaft 3 as a steering system accompanying the steering operation is converted into a reciprocating linear motion of the rack shaft 5 by the rack and pinion mechanism 4. The steering shaft 3 of this embodiment is formed by connecting a column shaft 3a, an intermediate shaft 3b, and a pinion shaft 3c. Then, the reciprocating linear motion of the rack shaft 5 accompanying the rotation of the steering shaft 3 is transmitted to a knuckle (not shown) via tie rods 6 connected to both ends of the rack shaft 5, whereby the steering angle of the wheel 7, That is, the traveling direction of the vehicle is changed.

  Further, the EPS 1 includes an EPS actuator 10 (actuator) that applies an assist force for assisting a steering operation to the steering system, and an ECU 11 as a control device that controls the operation of the EPS actuator 10.

  The EPS actuator 10 of this embodiment is configured as a so-called column-type EPS actuator in which a motor 12 as a driving source is drivingly connected to a column shaft 3 a via a speed reduction mechanism 13. The EPS actuator 10 is configured to apply the motor torque as an assist force to the steering system by decelerating the rotation of the motor 12 and transmitting it to the column shaft 3a.

  On the other hand, a torque sensor 14 and a vehicle speed sensor 15 are connected to the ECU 11. In the present embodiment, the torsion bar 17 is provided in the middle of the column shaft 3a constituting the steering shaft 3, and the torque sensor 14 detects the torsion of the torsion bar 17, that is, the steering torque that transmits the steering system. Accordingly, the output level of the sensor signal is changed. The ECU 11 calculates an assist force (target assist force) to be applied to the steering system based on the steering torque τ and the vehicle speed V detected by the torque sensor 14 and the vehicle speed sensor 15. The operation of the EPS actuator 10 is controlled through supply of driving power to the motor 12 in order to generate the target assist force in the EPS actuator 10 (power assist control).

  Further, the vehicle C of the present embodiment is provided with a vehicle control device 18 that executes automatic control related to the traveling behavior of the vehicle C, and the ECU 11 is connected to the vehicle control device 18 via an in-vehicle network (not shown). Yes. The ECU 11 of the present embodiment executes the vehicle control device 18 based on various state quantities and control signals acquired from the vehicle control device 18 in addition to the normal power assist control based on the steering torque τ as described above. Power assist control in cooperation with automatic control is performed (cooperative control).

  More specifically, the vehicle control device 18 according to the present embodiment, as its automatic control, actively changes the braking force distribution of each wheel, thereby suppressing vehicle slip stabilization control (ESC: Electronic) Run Stability Control. Specifically, the vehicle control device 18 determines the vehicle steering characteristic (understeer / oversteer) based on the state of the steering operation by the driver and the deviation between the target yaw rate calculated based on the vehicle model and the actual yaw rate. judge. When the vehicle is understeering, the braking force is applied to the inner rear wheel to increase the yaw moment of the vehicle. When the vehicle is oversteering, the braking force is applied to the outer front wheel. By giving, it controls so that the yaw moment of a vehicle may reduce. That is, such a vehicle control device 18 can turn the vehicle by controlling the distribution of the driving force between the left and right wheels of the vehicle.

  The ECU 11 of the present embodiment uses the steering angle of the steering wheel 2, the steering speed, the yaw rate deviation calculated in the vehicle behavior stabilization control, and the vehicle behavior as state quantities and control signals related to such vehicle behavior stabilization control. A state signal or the like indicating the execution state of the stabilization control is acquired from the vehicle control device 18 (others such as brake hydraulic pressure). Based on these state quantities and control signals, the vehicle behavior stabilization control target driving state in which skidding is unlikely to occur, that is, the driver's steering operation that causes the steering characteristic to be neutral steer is induced. And the cooperative control is executed so as to assist.

  The ECU 11 is connected to a display panel 19 as a notification unit. The display panel 19 is a display device that displays images showing various information to the driver based on information from the ECU 11.

  In the present embodiment, the ECU 11 has a plurality of modes, and performs control based on any of the set modes. The plurality of modes include a normal steering mode and a manual steering mode.

  The normal steering mode is set when there is no abnormality in the EPS actuator 10 and the assist force from the motor 12 is normally applied. When the normal steering mode is set, the assist force from the motor 12 is applied to the steering system in accordance with the steering of the steering 2. In the normal steering mode, cooperative control may be performed depending on the steering characteristics.

  On the other hand, the manual steering mode is set when there is an abnormality related to the EPS actuator 10 and the assist force from the motor 12 is not normally applied. In the present embodiment, the abnormality related to the EPS actuator 10 corresponds to a case where the ECU 11 and the torque sensor 14 and the like are normal, but an abnormality in which the application of the assist force from the motor 12 is stopped. In the present embodiment, the ECU 11 detects whether it is normal or abnormal based on a signal input from the motor 12 to the ECU 11.

  As described above, when the manual steering mode is set in accordance with the necessity of a large force for the steering of the steering 2, unlike the normal steering mode, a large force is not required for the steering of the steering 2. Control related to steering is changed, the vehicle is turned in accordance with the control, and assist force is applied. More specifically, when the steering torque τ applied by steering of the steering wheel 2 exceeds the upper threshold τ 2 (see FIG. 2), the vehicle control device 18 distributes the driving force on the left and right wheels of the vehicle regardless of the steering characteristic. The vehicle is turned in the steering direction of the steering 2 under control. As a result, an assist force is applied to the steering direction. In the manual steering mode, the cooperative control based on the steering characteristic that has been performed in the normal steering mode is not performed.

(Steering control mode)
Here, the aspect of the steering control in the manual steering mode in the EPS 1 of the present embodiment will be described with reference to FIGS.

  In the ECU 11, a lower limit threshold value τ1 and an upper limit threshold value τ2 are stored in advance. This lower limit threshold value τ1 is a threshold value for suppressing chattering due to the steering of the steering 2. The upper limit threshold τ2 is a threshold for detecting that the steering 2 has been steered. Note that the upper limit threshold τ2 is extremely smaller than the steering torque for turning the vehicle when the application of the assist force is stopped.

  In the manual steering mode, when the steering torque τ of the steering wheel 2 detected by the torque sensor 14 becomes less than the lower limit threshold value τ1 and then exceeds the upper limit threshold value τ2, steering for turning the vehicle has been performed. Detected. Note that after the steering torque τ exceeds the upper threshold τ2, it is detected that steering for turning the vehicle is performed on the condition that the steering torque τ is less than the lower threshold τ1. In this way, the steering 2 is steered small in the turning direction, and the steering torque τ exceeds the upper threshold τ2, so that the vehicle control device 18 controls the distribution of the driving force on the left and right wheels of the vehicle, thereby steering. It is detected that the vehicle is steered so as to apply assisting assisting force. Hereinafter, such steering is referred to as “click steering”.

  As a specific example, as shown in FIG. 2, when the steering torque τ exceeds the lower limit threshold τ1 from the state where the steering torque τ is less than the lower limit threshold τ1, and the steering torque τ exceeds the upper limit threshold τ2 at the timing of the symbol t1, The first click steering is detected. When the steering torque τ exceeds the upper limit threshold τ2 at the timing t3 after the steering torque τ becomes less than the lower threshold τ1 at the timing t2, the second click steering is detected. Once the steering torque τ exceeds the upper limit threshold τ2, it becomes less than the upper limit threshold τ2. However, if the steering torque τ exceeds the upper limit threshold τ2 again at the timing t4 without being less than the lower limit threshold τ1, click Steering is not detected. Then, after the steering torque τ becomes less than the lower limit threshold τ1 at the timing t5, when the steering torque τ exceeds the upper threshold τ2 at the timing t6, the third click steering is detected. Although not shown, when the lower limit threshold τ1 is exceeded from the lower limit threshold τ1 but the upper limit threshold τ2 is not exceeded, click steering is not detected. Note that the thresholds τ1 and τ2 are defined in the same manner regardless of whether the steering 2 is steered in any of the left and right directions.

  When click steering is detected in this way, a turning force is applied to the vehicle based on the detection result. As shown in FIG. 3, the turning force of the vehicle is set in a plurality of stages for each of the left and right directions. When click steering in the right direction is detected, the turning force of the vehicle is controlled to change to the right by one step. On the other hand, when click steering in the left direction is detected, the turning force of the vehicle is controlled to change to the left by one step.

  As a specific example, when the first click steering with respect to the right direction is detected in the state where the left and right turning forces are the same, the turning force in the right direction is increased by one step. Then, when the second click steering with respect to the right direction is detected in a state where the turning force in the right direction is increased by one step, the turning force in the right direction is further increased by one step, and the rightward turning force is increased. The turning force is increased by two stages. Thus, by repeating the click steering in the right direction, the turning force in the right direction with respect to the vehicle can be increased.

  In addition, when the first click steering in the left direction is detected in a state where the turning force in the right direction is increased by two steps, the turning force in the left direction is further increased by one step, and the rightward turning force is increased. The turning force is increased by one step. Then, when the second click steering with respect to the left direction is detected in a state where the rightward turning force is increased by one step, the leftward turning force is further increased by one step, and the left and right turning forces are increased. Are in the same state. Further, when the third click steering in the left direction is detected with the left and right turning forces being the same, the left turning force is increased by one step. Thus, by repeating the click steering in the left direction, the turning force in the left direction with respect to the vehicle can be increased.

  Therefore, when the application of the assist force by the motor 12 is stopped, the steering mode is set to the manual steering mode, and the turning force is applied to the vehicle by performing the click steering that does not require a large force for the steering 2. As a result, an assist force for assisting steering is applied.

(Control processing)
Here, the control process of the EPS 1 configured as described above will be described with reference to FIGS.

  First, the ECU 11 determines whether or not an abnormality relating to the EPS actuator 10 has occurred in accordance with a signal from the motor 12 or the like. When the ECU 11 determines that an abnormality relating to the EPS actuator 10 has not occurred, the ECU 11 sets a value indicating the normal steering mode in the mode flag. On the other hand, when the ECU 11 determines that an abnormality relating to the EPS actuator 10 has occurred, the ECU 11 sets a value indicating the manual steering mode in the mode flag. As a result, the ECU 11 sets one of a plurality of modes and performs switching control of each mode.

  Further, the ECU 11 outputs mode information indicating the set mode to the display panel 19. As a result, in the normal steering mode, an image indicating that the normal steering mode is set is displayed on the display panel 19 as shown in FIG. On the other hand, on the display panel 19, in the manual steering mode, as shown in FIG. 4B, an image indicating that the manual steering mode is set and that the click steering can be accepted. The image shown is displayed.

  The ECU 11 reads the value of the mode flag and determines whether or not the normal steering mode is set. When it is determined that the normal steering mode is set, the ECU 11 calculates an assist force to be applied to the steering system based on the steering torque τ and the vehicle speed V. The ECU 11 controls the operation of the EPS actuator 10 through the supply of driving power to the motor 12 based on the calculation result. Thereby, the ECU 11 performs normal power assist control.

  Further, the ECU 11 executes power assist control in cooperation with automatic control executed by the vehicle control device 18 based on various state quantities and control signals acquired from the vehicle control device 18. That is, the ECU 11 determines the steer characteristic of the vehicle, and when it is determined that the specific steer characteristic (understeer / oversteer) is based on the determination result, the ECU 11 controls the vehicle control device 18. Control the turning of the vehicle. On the other hand, the ECU 11 does not control the vehicle control device 18 when it is determined that it is not the specific steering characteristic.

  On the other hand, as shown in FIG. 5, the ECU 11 reads out the value of the mode flag and determines whether or not the manual steering mode is set (step S11). When it is determined that the manual steering mode is set, the ECU 11 executes a steering torque detection process for detecting the steering torque τ of the steering 2 based on the signal from the torque sensor 14 (step S12).

  Then, the ECU 11 determines whether or not the detected steering torque τ is greater than or equal to the upper threshold value τ2 (step S13). If the ECU 11 determines that the detected steering torque τ is greater than or equal to the upper limit threshold τ2, the ECU 11 determines whether or not the steering effective flag is “1”. This steering effective flag is a flag indicating whether or not click steering is effective, and is set to “1” on condition that the steering torque τ is less than the lower limit threshold τ1. That is, the ECU 11 determines whether or not the click steering is performed by determining whether or not the upper limit threshold τ2 is reached after the steering torque τ becomes less than the lower limit threshold τ1. When the ECU 11 determines that the steering effective flag is “1”, the ECU 11 proceeds to step S15.

  In step S15, the ECU 11 executes a steering angle change process. In this process, the ECU 11 reads the turning force data indicating the current turning force (steering angle), changes the turning force data to one turn in the turning direction corresponding to the click steering, and newly stores the turning force data. To do. As a specific example, the ECU 11 turns in which the turning force in the right direction is large by one step when one click steering in the right direction is detected in the current state where the same turning force is applied to the left and right. Change to force data. Further, the ECU 11 changes the turning force data to the turning force data which is larger by one step when the left turn force is detected in the current state where the left and right turn force is the same. . That is, the ECU 11 determines whether or not the steering torque τ detected by the torque sensor 14 has exceeded the upper limit threshold τ2 during an abnormality related to the EPS actuator 10, and the number of times the steering torque τ has exceeded the upper limit threshold τ2 (the number of steering operations). ) Will be counted.

  And ECU11 performs the steering information output process which outputs the steering information which shows this turning force to the vehicle control apparatus 18 (step S16). As a result, the vehicle control device 18 controls the distribution of the driving force on the left and right wheels of the vehicle on the basis of the steering information output by the ECU 11, thereby performing the control of applying the assist force by turning the vehicle. In other words, the ECU 11 performs control to apply the assist force by controlling the vehicle control device 18 according to the counted number of click steering operations.

  Subsequently, the ECU 11 executes a steering notification information output process for outputting steering notification information for notifying the change of the steering angle to the display panel 19 (step S17). Thereby, as shown in FIGS. 4C and 4D, the display panel 19 accepts click steering and displays an image indicating the current turning force indicating which steering direction has been changed.

  Specifically, when one click steering is detected in the right direction, as shown in FIG. 4 (c), an image operated in the right direction and a right direction are displayed on the display panel 19. And an image indicating that the turning force for one stage is applied. On the other hand, when one click steering is detected with respect to the left direction, as shown in FIG. 4D, an image operated in the left direction and a left direction are displayed on the display panel 19. An image indicating that the turning force for one stage is applied is displayed.

  That is, the ECU 11 performs control to notify the display panel 19 that notifies the driver that the steering torque detected by the torque sensor 14 exceeds the upper threshold τ2 and click steering is detected. . Then, the ECU 11 sets “0” in the steering effective flag (step S18). As a result, the ECU 11 can specify that the steering torque τ has exceeded the upper limit threshold τ2.

  On the other hand, if the ECU 11 determines that the detected steering torque τ is not greater than or equal to the upper limit threshold τ2, the ECU 11 determines whether the detected steering torque τ is less than the lower limit threshold τ1 (step S19). When the ECU 11 determines that the detected steering torque τ is less than the lower limit threshold τ1, the ECU 11 sets “1” in the steering effective flag (step S20). As a result, the ECU 11 can specify that the steering torque τ is less than the upper limit threshold τ1. Then, the ECU 11 executes a steering non-notification information output process for outputting the steering non-notification information for notifying that the steering angle has been changed and that the click steering can be accepted to the display panel 19 (step S20). As a result, the display panel 19 displays an image indicating that click steering can be accepted, as shown in FIG. That is, the ECU 11 performs control to notify the display panel 19 that notifies the driver that the steering torque detected by the torque sensor 14 is less than the lower threshold τ1.

  In this embodiment, in this manual steering mode, the ECU 11 stops the control for driving the motor 12 and only determines whether or not an abnormality relating to the EPS actuator 10 has occurred based on the signal from the motor 12. Judgment. In the present embodiment, when a predetermined time has elapsed since the previous click steering was detected, the turning force data is initialized to distribute the driving force on the left and right wheels of the vehicle. Thus, the control is performed so as not to apply the assist force by controlling. In the present embodiment, the ECU 11 that executes such control processing functions as a steering torque determination unit that determines the steering torque and a steering number counting unit that counts the number of steerings.

(Effect of embodiment)
As described above in detail, the present embodiment has the following effects.
(1) Even when the EPS actuator 10 is abnormal, steering is assisted by controlling the distribution of the driving force between the left and right wheels of the vehicle according to the number of times the steering torque has been steered exceeding the upper threshold τ2. Assist power can be applied. Therefore, it is possible to facilitate steering as intended by the driver without continuing to apply a large steering torque by steering in the event of an abnormality related to the EPS actuator 10.

  (2) Further, the assist force for assisting the steering can be controlled by the steering 2. For this reason, compared with steering by other operation means, the safety when driving the vehicle is improved by using the steering 2 used in normal driving without greatly changing the steering posture of the driver. be able to.

  (3) The driver can recognize that the steering torque τ applied to the steering system by the steering of the steering wheel 2 has exceeded the upper limit threshold τ2, and it can be specified that the assist force assisting the steering is applied. Become.

  (4) An assist force for assisting steering can be applied to the steering direction, and the vehicle can be smoothly turned according to the driver's steering even when the EPS actuator 10 is abnormal. In addition, compared with steering by other operating means, using the steering 2 that is used in normal driving, it is possible to improve safety when driving the vehicle without greatly changing the steering posture of the driver. Can do.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. In the following description, the same components as those in the first embodiment described above are denoted by the same reference numerals, and redundant description thereof is omitted or simplified.

  In the first embodiment, the control for applying the assist force in the turning direction corresponding to the steering direction detected by the torque sensor 14 is performed. On the other hand, in 2nd Embodiment, control which gives the assist force with respect to the turning direction corresponding to the instruction | indication direction instruct | indicated with the direction indicator (instruction | indication means) provided separately from steering is performed.

  Specifically, as shown in FIG. 6, the ECU 11 is connected with a direction indicator 20 for instructing one of the left and right instruction directions in which the vehicle C travels. The ECU 11 performs control for blinking a direction indicator lamp (not shown) based on a direction indication signal from the direction indicator 20. Further, when the ECU 11 is set to the manual steering mode, if the direction indicator signal indicating the indicated direction is input from the direction indicator 20, the ECU 11 applies a turning force to the vehicle in the direction. Thus, the turning of the vehicle is controlled.

  (5) An assisting force for assisting steering can be applied in a steering direction corresponding to the instruction direction instructed by the direction indicator 20, and even when the EPS actuator 10 is abnormal, according to the driver's steering. The vehicle can be turned smoothly. Further, compared to steering by other operating means, the steering 2 and the direction indicator 20 that are used in normal driving are used to drive the vehicle without significantly changing the steering posture of the driver. Safety can also be improved.

In addition, the said embodiment can be embodied in another embodiment (another example) as follows.
-In 2nd Embodiment, although the direction indicator as an instruction | indication means was not included in EPS1, and it was set as the structure mounted in the vehicle, it is not restricted to this, For example, even if it is the structure where a direction indicator is included in EPS1 Good.

  In the above embodiment, the display panel 19 as the notification unit is not included in the EPS 1 and is mounted on the vehicle. However, the present invention is not limited thereto, and for example, the display panel 19 may be included in the EPS 1. .

  In the above embodiment, the display panel 19 displays an image to notify that the steering torque τ is equal to or greater than the upper limit threshold τ2. However, the present invention is not limited to this, for example, by outputting sound from a speaker. May be. Further, for example, the notification may be made by vibrating the steering 2 or the like. Moreover, these combinations may be sufficient. In addition, there is no problem even if such a notification is not performed.

  In the above embodiment, the turning force data is initialized when the specified time has elapsed after the click steering is detected. However, the present invention is not limited to this, and the turning force data is initialized when other conditions are satisfied. You may comprise. For example, the structure which does not initialize turning force data may be sufficient.

  In the above embodiment, both the lower limit threshold τ1 and the upper limit threshold τ2 are set. However, the present invention is not limited to this, and the upper limit threshold τ2 may be defined without setting the lower limit threshold τ1. That is, the number of times of steering may be counted with a minimum condition that the steering torque detected by the torque sensor exceeds a threshold value.

  In the above embodiment, even when a signal is input from the motor 12 to the ECU 11, an abnormality related to the EPS actuator 10 is detected, but when the signal is not input, an abnormality related to the EPS actuator 10 is detected. It may be a configuration.

  In the above embodiment, the ECU 11 is configured not to control the drive of the motor 12 when an abnormality relating to the EPS actuator 10 is detected in accordance with a signal from the motor 12. Regardless of whether the motor is driven or not, there is no problem even if it is configured to control the driving of the motor 12.

  In the above embodiment, not only when there is an abnormality in the EPS actuator 10 itself, but also when there is no abnormality in the EPS actuator 10 itself, when the EPS actuator 10 is not controlled due to other factors, an abnormality related to the EPS actuator 10 May be configured to be detected. Further, for example, a configuration in which an abnormality relating to the EPS actuator 10 is detected when a signal from the ECU 11 to the motor 12 is not output may be employed. That is, when the assist force by the EPS actuator 10 is not applied, an abnormality relating to the EPS actuator 10 may be detected.

  In the above embodiment, each mode is switched when an abnormality relating to the EPS actuator 10 is detected according to a signal from the motor 12. However, the present invention is not limited to this. For example, each mode is switched according to an operation. You may go. That is, each mode may be switchable according to an operation of a driver or a mechanic for a stopped vehicle or a vehicle under maintenance.

  In the above embodiment, the steering characteristic of the vehicle is determined based on the state of the steering operation by the driver and the deviation between the target yaw rate calculated based on the vehicle model and the actual yaw rate. However, the present invention is not limited to this.

  In the above embodiment, the manual steering mode is configured such that the cooperative control based on the steer characteristic is not performed. However, the present invention is not limited thereto, and the cooperative control based on the steer characteristic may also be performed.

  In the above embodiment, the vehicle may be turned by controlling the drive distribution of the left and right rear wheels. Further, the vehicle may be turned by controlling the drive distribution of the left and right front wheels and the rear wheels.

  In the above embodiment, the present invention is mounted on a vehicle equipped with an ESC. However, the present invention is not limited to this, and the vehicle is controlled to turn left and right by controlling the distribution of driving force on the left and right wheels of the vehicle. The present invention may be mounted on such a vehicle.

  In the above-described embodiment, the vehicle may be turned by controlling the distribution of the brakes instead of the distribution of the driving force on the left and right wheels. Specifically, the vehicle can be turned by changing the brake distribution on the left and right wheels as in the anti-lock brake system.

In the above embodiment, the column type EPS 1 is embodied. However, the present invention may be applied to a so-called pinion type or rack assist type EPS.
In the above embodiment, the present invention is applied to the electric power steering apparatus. However, the present invention is not limited to this, and the present invention may be applied to a hydraulic power steering apparatus.

Next, a technical idea that can be grasped from the above embodiment and another example will be added below.
(A) Steering applied to a steering system by steering in a power steering device mounted on a vehicle having a vehicle control device that turns the vehicle by controlling the distribution of driving force or the distribution of brakes on the left and right wheels of the vehicle A torque sensor that detects torque, an actuator that applies an assist force that assists steering to the steering system, and a control that controls the assist force by controlling the actuator according to the steering torque detected by the torque sensor The control device determines whether or not the steering torque detected by the torque sensor exceeds a threshold value when an abnormality relating to the actuator is detected, and determines that the steering torque exceeds the threshold value In addition, the distribution of the driving force on the left and right wheels of the vehicle or the brake It is to control the distribution, power steering device and performs the control for imparting an assist force for assisting the steering.

  (B) In the power steering device according to any one of claims 1 to 4, the control device includes a steering characteristic determination unit that determines a steering characteristic of a vehicle. While controlling the turning of the vehicle by controlling the vehicle control device based on the result determined by the characteristic determination means, while abnormal in relation to the actuator, regardless of the result determined by the steering characteristic determination means, According to the number of steering operations, the vehicle control device controls the distribution of the driving force or the distribution of the brakes on the left and right wheels of the vehicle, thereby performing a control for providing an assist force for assisting the steering. Power steering device.

  (C) In the power steering device according to any one of claims 1 to 4, the control device includes an abnormality determination unit that determines whether or not the power steering device is abnormal. A power steering apparatus that performs control to apply an assist force that assists steering by controlling the vehicle control apparatus with different control contents depending on the result determined by the abnormality determination means.

  C: Vehicle, τ: Steering torque, τ1: Lower threshold, τ2: Upper threshold, 1 ... Electric power steering device, 2 ... Steering, 3 ... Steering shaft, 7 ... Wheel, 11 ... ECU, 12 ... Motor, 14 ... Torque Sensor, 18 ... Vehicle control device, 19 ... Display panel, 20 ... Direction indicator.

Claims (3)

In a power steering device mounted on a vehicle having a vehicle control device for turning the vehicle by controlling the distribution of driving force or the distribution of brakes on the left and right wheels of the vehicle,
A torque sensor for detecting a steering torque applied to the steering system by steering;
An actuator for applying an assist force to assist the steering to the steering system;
A control device that controls the assist force by controlling the actuator according to a steering torque detected by the torque sensor;
The control device counts the number of steerings on the condition that the steering torque detected by the torque sensor exceeds a threshold value when there is an abnormality related to the actuator, and in response to the number of steerings, A power steering apparatus that performs control to apply assist force for assisting steering by controlling distribution of driving force or distribution of brakes on left and right wheels of a vehicle. The power steering apparatus according to claim 1, wherein
The control device performs control for notifying to a driver that a steering torque detected by the torque sensor exceeds a threshold value when an abnormality related to the actuator is exceeded. Steering device. In the power steering device according to claim 1 or 2,
The control device controls the vehicle control device so that the assist force is applied to a steering direction detected by the torque sensor when an abnormality occurs in the actuator.