JP2008207783A - Steering gear for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steering gear for a vehicle capable of reducing cost by reducing the number of sensors and miniaturizing a reaction motor. <P>SOLUTION: This steering gear for the vehicle detects a manipulated variable of a steering wheel by a steering angle sensor in a state where mechanical connection of the steering wheel and a steering gear box is cut off, converts a detected value to an electric signal, steers wheels by driving a steering motor provided in the steering gear box in accordance with the electric signal and gives steering reaction to the steering wheel by driving the steering reaction motor connected to the steering wheel in correspondence with the manipulated variable. This steering gear for the vehicle is furnished with a clutch mechanism having a planetary gear capable of mechanically connecting the steering wheel and the steering gear box to each other and controls a lock wheel constituting a part of the clutch mechanism by a brushless motor. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a technique for improving a steer-by-wire vehicle steering apparatus having a backup mechanism.

  2. Description of the Related Art Conventionally, as a general vehicle steering apparatus, a structure in which a steering mechanism is connected to a steering wheel and wheels are steered via the steering mechanism by a steering force of the steering wheel is known.

  In recent years, the steering mechanism is mechanically separated from the steering wheel, the steering motor generates steering power according to the steering amount, and the steering power is transmitted to the steering mechanism to steer the wheels. A steer-by-wire (steer-by-wire, hereinafter referred to as “SBW”) vehicle steering device is known.

In such a vehicle steering apparatus, since the steering wheel and the steering gear box are not mechanically connected, if the steering motor fails, the wheel may not be steered even if the steering wheel is operated. Therefore, in the conventional steer-by-wire vehicle steering apparatus, a rotation restricting mechanism is disposed between the steering wheel and the steering gear box, and when the steering motor is functioning normally, the rotation restricting mechanism When the mechanical connection with the steering gear box is cut off and the steering motor fails, the steering wheel and the steering gear box are mechanically connected with a rotation restricting mechanism so that the wheels can be steered (for example, Patent Document 1). reference.).
JP-A-2005-29016

  By the way, in the steer-by-wire vehicle steering device described above, unlike a conventional general vehicle steering device, if the steering angle sensor or pinion sensor fails, the steering operation is hindered. A failure mode is detected by providing two systems of angle sensors and pinion sensors and comparing these detection values with each other. Therefore, there has been a problem that the cost becomes higher than that of a conventional general vehicle steering apparatus.

  In the above steer-by-wire vehicle steering system, the steering reaction force needs to be abruptly increased at the steering wheel handle end in order to inform the driver of the steering wheel handle end state. There is a problem that the reaction force motor for applying the steering reaction force cannot be reduced in size.

  Accordingly, the present invention has been made in view of the above-described problems, and an object thereof is to provide a vehicle steering apparatus capable of reducing the cost by reducing the number of sensors and miniaturizing the reaction force motor. .

The present invention proposes the following matters in order to solve the above problems.
(1) In the present invention, in a state where the mechanical connection between the steering wheel and the steering gear box is cut off, the operation amount of the steering wheel is detected by a steering angle sensor, and the detected value is converted into an electric signal. The steering motor provided in the steering gear box is driven based on the above to steer the wheel, and the steering reaction force motor connected to the steering wheel is driven according to the operation amount to apply the steering reaction force to the steering wheel. In the vehicle steering apparatus, a clutch mechanism having planetary gears capable of mechanically connecting the steering wheel and the steering gear box (for example, the sun gear 71, the planetary gear 72, the internal gear 73, and the lock wheel in FIG. 2). 81) and a lock wheel that forms part of the clutch mechanism (for example, the lock shown in FIG. 2) A vehicle steering apparatus comprising a control means (e.g., corresponding to the control unit 61 of Fig. 1) for controlling an Eel 81) by a brushless motor (e.g., corresponding to the brushless motor 82 of Fig. 2). is suggesting.

  According to the present invention, the gear ratio can be controlled by controlling the lock wheel forming a part of the clutch mechanism by the brushless motor. Further, unlike the lock mechanism using the conventional lock pin, the lock wheel is controlled by the brushless motor, so that it is possible to prevent the backlash at the time of the lock that has occurred in the conventional lock mechanism.

(2) The present invention relates to the vehicle steering device of (1), with a steering angle sensor (for example, equivalent to the steering angle sensor 23 in FIG. 1), a pinion sensor (for example, equivalent to the pinion sensor 41 in FIG. 1), and a brushless. A failure detection means for detecting a failure of the rotation angle sensor of the motor (for example, corresponding to the failure determination unit 67 of FIG. 3) is provided, and the rotation angle θ _{S of the} brushless motor and the rotation angle of the handle detected from the steering angle sensor When θ _h and the rotation angle θ _{P of the} pinion detected from the pinion sensor do not satisfy a · θ _h = b · θ _S + c · θ _P (where a, b, and c are constants), The vehicle steering apparatus is characterized in that the failure detection means detects a failure of at least one of the steering angle sensor, the pinion sensor, and the rotation angle sensor of the brushless motor.

According to the present invention, more rotation angle theta _P of the pinion detected from the rotation angle theta _h and pinion sensor handles detected from the rotational angle theta _S and the steering angle sensor of the brushless motor, at least the steering angle sensor or pinion sensor Alternatively, since any failure of the rotation angle sensor of the brushless motor can be detected, the number of sensors can be reduced as compared with the conventional steer-by-wire system. Further, since the presence / absence of a failure is determined by the above relational expression, the presence / absence of a sensor failure can be reliably detected.

  (3) The present invention provides the vehicle steering apparatus according to (1) or (2), further comprising sensor output detection means for detecting an output of the steering angle sensor, wherein the sensor output detection means is configured such that the steering wheel locks the steering wheel. A vehicle steering apparatus characterized in that the control means (e.g., corresponding to the brushless motor control unit 68 in FIG. 5) stops the rotational operation of the brushless motor when it is detected that the state is close to is suggesting.

  According to this invention, when the steering wheel is close to the handle lock, the steering reaction force is applied by a mechanical force by stopping the rotation of the brushless motor, and therefore the torque of the reaction force motor is used. Thus, the driver can be informed of the steering wheel lock state.

  (4) The present invention is directed to the vehicle steering device according to (3), comprising drive control means (for example, corresponding to the drive control unit 69 in FIG. 8) for controlling the driving of the steering motor and the reaction force motor, and the steering wheel. The control means (e.g., corresponding to the brushless motor control unit 68 in FIG. 8) performs position control for stopping the rotation operation of the brushless motor, and the drive control means includes a steering motor and a reaction force motor. Has proposed a vehicle steering device characterized in that the wheels are steered by controlling the driving of the vehicle.

  According to the present invention, when the steering wheel is stationary, the rotation of the brushless motor is stopped, and the wheels are steered by controlling the driving of the steering motor and the reaction force motor. Rudder followability can be improved.

  According to the present invention, the rotation angle sensor of the brushless motor and the steering angle sensor are determined depending on whether or not a predetermined relational expression is satisfied from the output of the steering angle sensor and the output of the pinion sensor using the rotation angle sensor of the brushless motor. In addition, since the failure of the pinion sensor can be detected, there is an effect that the number of sensors can be reduced and the cost can be reduced as compared with the conventional case.

  In addition, when the steering wheel is close to the handle lock, by stopping the rotation of the brushless motor, the steering reaction force is applied by a mechanical force, so that the reaction motor can be reduced in size. .

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Note that the constituent elements in the present embodiment can be appropriately replaced with existing constituent elements and the like, and various variations including combinations with other existing constituent elements are possible. Therefore, the description of the present embodiment does not limit the contents of the invention described in the claims.

<Configuration of vehicle steering device>
The configuration of the vehicle steering apparatus according to the present embodiment will be described with reference to FIG.
The vehicle steering device 10 mechanically separates the steering mechanism 30 from the steering wheel 21 as a steering member, generates steering power from the steering motor 38 according to the steering amount of the steering wheel 21, and this steering. This is a so-called steer-by-wire (SBW) type vehicle steering apparatus in which left and right steered wheels 35 and 35 are steered by the steered mechanism 30 by transmitting motive power to the steered mechanism 30.

  The steering mechanism 20 of the vehicle steering apparatus 10 includes a steering wheel 21 gripped by a driver, a steering shaft 22 connected to the steering wheel 21, a steering angle sensor 23 that detects a steering angle of the steering wheel 21, and a steering force. A torque sensor 32 to detect, a reaction force motor 24 that generates a steering reaction force (reaction torque) against the steering wheel 21, a motor rotation angle sensor 25 that detects a rotation angle of the reaction force motor 24, and a steering reaction force. A reaction force transmission mechanism 26 that transmits to the shaft 22 is configured.

  Here, the reaction force motor 24 is an electric motor, and the reaction force transmission mechanism 26 is coupled to the worm 27 provided on the motor shaft of the reaction force motor 24 and the steering shaft 22, and the worm wheel meshed with the worm 27. 28 is a worm gear mechanism, that is, a booster mechanism. The steering reaction force is an operation resistance added to the steering wheel 21 in the rotational direction.

  The turning mechanism 30 includes an input shaft 31 for inputting a steering force of the steering shaft 22, a rack shaft 34 connected to the input shaft 31 via a rack and pinion mechanism 33, and left and right turning wheels at both ends of the rack shaft 34. Tie rods 36 and 36 and knuckles 37 and 37 that connect 35 and 35 (for example, front wheels), a steering motor 38 that adds power for turning to the input shaft 31, and a pinion sensor 41 that detects the rotation angle of the input shaft 31; , Is composed of.

  The rack and pinion mechanism 33 includes a pinion 43 formed on the input shaft 31 and a rack 44 formed on the rack shaft 34. The steering motor 38 includes a turning power motor 45 that generates turning power and a turning power transmission mechanism 46 that transmits the turning power to the input shaft 31. Here, the turning power motor 45 is an electric motor. The turning power transmission mechanism 46 includes a worm 47 provided on the motor shaft of the turning power motor 45 and a worm gear 48 that is coupled to the input shaft 31 and meshed with the worm 47, that is, a boosting mechanism. It is.

  As described above, the vehicle steering apparatus 10 is a steering apparatus that extracts the steering torque from both ends of the rack shaft 34. Further, the vehicle steering apparatus 10 is configured such that a planetary gear mechanism 51 connects a steering shaft 22 provided on the steering wheel 21 and an input shaft 31 provided on the steering mechanism 30. Specifically, the input shaft 31 is connected to the steering shaft 22 via the planetary gear mechanism 51, the first connecting shaft 52, the first universal shaft joint 53, the second connecting shaft 54, and the second universal shaft joint 55. It is what.

  In addition, the control unit 61 receives detection signals from the rudder angle sensor 23, the motor rotation angle sensor 25, the turning torque sensor 32, the pinion sensor 41, and the brushless motor provided in the planetary gear mechanism 51, and the traveling speed of the vehicle. Vehicle speed sensor 62 for detecting the yaw rate, yaw rate sensor 63 for detecting the yaw angular velocity (the angular velocity of yaw motion), acceleration sensor 64 for detecting the acceleration of the vehicle, and various other sensors 65 to receive the detection signals, respectively, A control signal is issued to the lock solenoid in the turning power motor 45 and the planetary gear mechanism 51.

  That is, the control unit 61 automatically sets the steering reaction force according to the operation of the steering wheel 21 by controlling the reaction force motor 24, adds the steering reaction force to the steering wheel 21, and Control can be performed as in 1) to (4).

(1) When a torque in the direction opposite to the steering direction of the steering wheel 21 is applied to the worm wheel 28 by the reaction force motor 24, the steering force of the steering wheel 21 is canceled by the steering reaction force of the reaction force motor 24. Work. For this reason, when the steering wheel 21 is steered, a steering force that is larger by the steering reaction force by the reaction force motor is required.

(2) When a torque in the same direction as the steering direction of the steering wheel 21 is applied to the worm wheel 28 by the reaction force motor 24, there is an effect of adding the steering reaction force of the reaction force motor 24 to the steering force of the steering wheel 21. work. For this reason, when the steering wheel 21 is steered, a steering force that is smaller by the amount corresponding to the steering reaction force by the reaction force motor is sufficient.

(3) When the steering wheel 21 is held at an arbitrary angle in a stopped state, the worm wheel 28 is adjusted while adjusting the steering reaction force of the reaction force motor 24 in the direction opposite to the rotation direction of the steering wheel 21 until then. A holding force is generated by rotating the.

(4) When the steering wheel 21 is subsequently returned, a return force (steering reaction force) corresponding to so-called self-aligning torque that automatically returns the steering wheel 21 to the neutral position of the steering wheel 21 is a reaction force motor. 24 is transmitted to the worm wheel 28.

  Further, the control unit 61 automatically sets the characteristics of the angle ratio of the steered wheels 35 and 35 to the steering angle of the steering wheel 21, that is, the steering characteristics, by controlling the steered power motor 45. can do. That is, since the steering mechanism 30 is mechanically separated from the steering wheel 21 as described above, the correspondence relationship between the steering angle of the steering wheel 21 and the operation amount of the steering motor 38 is set without any mechanical restriction. be able to. As a result, the steering characteristics can be flexibly set according to the traveling state of the vehicle, such as the vehicle speed, the degree of turning of the vehicle, and the presence or absence of acceleration / deceleration. Accordingly, the degree of freedom in designing the vehicle steering apparatus 10 can be increased.

  Further, the control unit 61 mechanically connects the steering wheel 21 and the planetary gear mechanism 51 by stopping the rotation operation of a brushless motor (to be described later) that controls the rotation of the lock wheel in the planetary gear mechanism 51 at the time of locking. The wheels can be steered.

<Configuration of clutch mechanism>
Next, the configuration of the clutch mechanism will be described with reference to FIG.
FIG. 2 is a schematic diagram of the clutch mechanism according to the present embodiment. As described above, the first connecting shaft 52 is connected to the input shaft 31 shown in FIG. 1, and the first connecting shaft 52 can be substantially replaced with the input shaft 31. .

The planetary gear mechanism 51 meshes a plurality of, for example, three planetary gears 72 (... indicates a plurality; the same applies hereinafter) with the central sun gear 71, and these planetary gears 72 ... And a plurality of planetary gears 72... Are rotatably attached to the carrier 74.

  The sun gear 71, the internal gear 73, and the carrier 74 are arranged on the center of the first connecting shaft 52, and the first connecting shaft 52 supports the sun gear 71 so as to be relatively rotatable. The plurality of planetary gears 72 are arranged radially with an equal pitch with respect to the sun gear 71.

  Further, the planetary gear mechanism 51 connects the internal gear 73 to the steering shaft 22, connects the carrier 74 to the first connection shaft 52, maintains the sun gear 71 in a normally rotatable state, and locks from the control unit 61. A lock mechanism 80 that locks in a stopped state by a signal Cn is provided.

  The lock mechanism 80 includes a lock wheel 81 provided integrally with the sun gear 71 and a brushless motor 82 that controls the rotation of the lock wheel 81. The lock wheel 81 is a member that can relatively rotate on the center of the first connecting shaft 52. In this embodiment, since the lock wheel 81 is controlled by the brushless motor 82, the gear ratio can be controlled. Further, it is possible to prevent rattling at the time of locking, which has conventionally occurred in a locking mechanism provided with a claw member.

  The steering unit case 91 indicated by an imaginary line is a storage member that attaches the reaction force motor 24 and stores the reaction force transmission mechanism 26 and the planetary gear mechanism 51. In the figure, 92 is a first bearing that supports the steering shaft 22, 93 and 93 are second bearings that support the first connecting shaft 52, and 94 is a third bearing that supports the internal gear 73.

<Sensor failure detection processing>
A sensor failure detection process in the vehicle steering apparatus according to the present embodiment will be described with reference to FIGS. 3 and 4.
As shown in FIG. 3, the configuration block for detecting a sensor failure includes a pinion sensor 41, a rudder angle sensor 23, a rotation angle sensor of the brushless motor 82, a calculation unit 66 that forms part of the control unit 61, And a failure determination unit 67.

  Here, the pinion sensor 41 detects the rotation angle of the pinion, and the steering angle sensor 23 detects the rotation angle of the steering wheel 21. The brushless motor 82 detects the rotation angle of the sun gear 71 by detecting the rotation angle of the lock wheel 81 using a built-in rotation angle sensor.

The calculation unit 66 calculates a · θ from the rotation angle θ _S of the brushless motor 82, the rotation angle θ _h of the steering wheel 21 detected from the steering angle sensor 23, and the pinion rotation angle θ _P detected from the pinion sensor 41. _h = b · θ _S + c · θ _P (where a, b, and c are constants) are calculated. The failure determination unit 67 determines whether or not the rudder angle sensor 23 and the pinion sensor 41 or the rotation angle sensor of the brushless motor are normal based on whether or not the above equation is established by calculation by the calculation unit 66.

Next, sensor failure detection processing will be described with reference to FIG.
First, the pinion sensor 41, the rudder angle sensor 23, and the brushless motor 82 detect the rotation angle θ _{P of the} pinion, the rotation angle θ _h of the steering wheel 21, and the rotation angle θ _S of the brushless motor 82, respectively (step S101). The calculation unit 66 inputs the pinion sensor 41, the rudder angle sensor 23, the pinion rotation angle θ _P detected by the brushless motor 82, the rotation angle θ _h of the steering wheel 21 and the rotation angle θ _S of the brushless motor 82, and a · An operation of θ _h = b · θ _S + c · θ _P (where a, b, and c are constants) is executed.

  Then, the failure determination unit 67 determines whether or not this arithmetic expression is established (step S102). If the result of the determination is that this formula is satisfied (“Yes” in step S102), it is determined that the rudder angle sensor 23, the pinion sensor 41, and the rotation angle sensor of the brushless motor are all normal (step S103). When the arithmetic expression is not satisfied (“No” in step S102), it is determined that at least one of the steering angle sensor 23, the pinion sensor 41, and the rotation angle sensor of the brushless motor is abnormal (step S104).

Therefore, according to the sensor failure detection processing described above, at least from the rotation angle θ _S of the brushless motor, the rotation angle θ _{h of the} handle detected from the steering angle sensor, and the rotation angle θ _{P of the} pinion detected from the pinion sensor, Failure of either the steering angle sensor, pinion sensor or brushless motor rotation angle sensor can be detected, so the number of sensors for ensuring reliability can be reduced compared to the conventional steer-by-wire system . Further, since the presence / absence of a failure is determined by the above relational expression, the presence / absence of a failure of the sensor can be reliably detected.

<Processing when the handle is locked>
With reference to FIGS. 5 and 6, a process when the steering wheel is locked in the vehicle steering apparatus according to the present embodiment will be described. In the present embodiment, “handle lock” refers to a state in which the gear box does not move even when torque is input to the handle, that is, a state in which the rack end of the gear box or the tire is hitting the curb.
As shown in FIG. 5, the configuration block that performs the process at the time of the handle lock is configured by a rudder angle sensor 23, a brushless motor control unit 68 that forms part of the control unit 61, and a brushless motor 82.

  Here, the steering angle sensor 23 detects the rotation angle and rotation speed of the steering wheel 21. The brushless motor control unit 68 controls the rotation of the brushless motor 82 by detecting the handle lock state of the steering wheel 21 based on the rotation angle and rotation speed information of the steering wheel 21 detected by the rudder angle sensor 23.

Next, the processing at the time of handle lock will be described with reference to FIG.
First, the rudder angle sensor 23 detects the rotation angle and rotation speed of the steering wheel 21 (step S201). The brushless motor control unit 68 detects whether or not the steering wheel 21 is in the handle lock state based on the rotation angle and rotation speed information of the steering wheel 21 detected by the rudder angle sensor 23. Specifically, the brushless motor control unit 68 has a pinion angle in the vicinity of the rack end, the rotation angle of the steering wheel 21 detected by the steering angle sensor 23 is in the vicinity of the maximum value, and the pinion angle rotation speed is in the vicinity of zero. At this time, it is determined that the steering wheel 21 is in the handle lock state (“Yes” in step S202). Then, the brushless motor control unit 68 stops the rotation of the brushless motor 82 (step S203).

  In the present embodiment, the processing shown in FIG. 7 is performed in order to cope with a case where a tire enters a groove or hits a curb. That is, the brushless motor control unit 68 detects the steering motor torque and the pinion rotation angle (step S401). Then, it is detected whether or not the steering motor torque is near the output upper limit (step S402). If the steering motor torque is near the output upper limit ("Yes" in step S402), then the pinion It is detected whether or not the angular rotation speed is near zero. If the pinion angular rotation speed is near zero, the rotation operation of the brushless motor 82 is stopped.

  Therefore, according to the above-described processing at the time of locking the steering wheel, when the steering wheel 21 is in a state close to the steering wheel lock, by stopping the rotation of the brushless motor 82, the steering derived from the mechanical lock state of the gear box. Since the reaction force is applied, the driver can be informed of the steering wheel lock state of the steering wheel 21 without using the torque of the reaction force motor 24. Further, since the torque of the reaction force motor 24 is not used, the reaction force motor 24 can be reduced in size.

<Processing when the steering wheel is stationary>
A process when the steering wheel is stationary in the vehicle steering apparatus according to the present embodiment will be described with reference to FIGS. 8 and 9.
As shown in FIG. 8, the structural block for performing the steering wheel stationary operation is a rudder angle sensor 23, a sensor output acquisition unit 70, a vehicle speed sensor 62, and a brushless motor control that forms part of the control unit 61. The unit 68, the drive control unit 69, the reaction force motor 24, the steering motor 38, and the brushless motor 82 are configured.

  Here, the steering angle sensor 23 detects the rotation angle of the steering wheel 21, and the vehicle speed sensor 62 detects the traveling speed of the vehicle. The sensor output acquisition unit 70 acquires values detected by the rudder angle sensor 23 and the vehicle speed sensor 62 and outputs the values to the brushless motor control unit 68 and the drive control unit 69. When the brushless motor control unit 68 and the drive control unit 69 determine that the operation mode is when the steering wheel 21 is stationary based on the detection value input from the sensor output acquisition unit 70, the reaction force motor 24, the steering The motor 38 and the brushless motor 82 are controlled.

Next, the processing at the time of turning off the steering wheel will be described with reference to FIG.
First, the steering angle sensor 23 detects the rotation angle of the steering wheel 21, and the vehicle speed sensor 62 detects the traveling speed of the vehicle (step S301). The brushless motor control unit 68 and the drive control unit 69 set the operation mode to the setting of the steering wheel 21 when the detection value of the vehicle speed sensor 62 is zero, that is, when the vehicle is stopped and there is an output from the rudder angle sensor 23. The brushless motor control unit 68 stops the rotation of the brushless motor 82, and the drive control unit 69 drives the reaction force motor 24 and the steering motor 38. The wheels are steered (step S303).

  Therefore, according to the above-described process for steering the steering wheel, when the steering wheel 21 is stationary, the rotation of the brushless motor 82 is stopped, and the driving of the steering motor 38 and the reaction force motor 24 is controlled to rotate the wheel. Since the steering is performed, it is possible to improve the steering followability with respect to the steering wheel operation at the time of stationary.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes a design and the like within a scope not departing from the gist of the present invention.

It is a lineblock diagram of the steering device for vehicles concerning this embodiment. It is a mimetic diagram of a clutch mechanism concerning this embodiment. It is a block diagram for a sensor failure detection process in the vehicle steering apparatus according to the present embodiment. It is a failure detection processing flow of the sensor in the vehicle steering device according to the present embodiment. It is a block diagram for the processing at the time of handle lock in the vehicle steering apparatus according to the present embodiment. It is a processing flow at the time of the steering wheel lock in the steering device for vehicles concerning this embodiment. It is a processing flow of the modification regarding the process at the time of the steering wheel lock in the steering device for vehicles which concerns on this embodiment. It is a block diagram for a process for steering the steering wheel in the vehicle steering apparatus according to the present embodiment. It is a processing flow at the time of a steering wheel stationary in the steering device for vehicles concerning this embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Steering device for vehicles, 21 ... Steering wheel, 23 ... Steering angle sensor, 24 ... Reaction force motor, 38 ... Steering motor, 41 ... Pinion sensor, 61 ... Control part, 62 ... Vehicle speed sensor, 66 ... Calculation part, 67 ... Failure determination part, 68 ... Brushless motor control part, 69 ... Drive control part, 70 ... Sensor output acquisition part 81 ... Lock wheel, 82 ... Brushless motor

Claims (4)

With the mechanical connection between the steering wheel and the steering gear box disconnected, the steering wheel operation amount is detected by the rudder angle sensor, and the detected value is converted into an electric signal. Based on the electric signal, the steering gear box is In a vehicle steering apparatus for driving a provided steering motor to steer a wheel and driving a steering reaction force motor connected to the steering wheel according to the operation amount to apply a steering reaction force to the steering wheel.
A clutch mechanism having a planetary gear capable of mechanically connecting the steering wheel and the steering gear box;
A vehicle steering apparatus comprising a control means for controlling a lock wheel forming a part of the clutch mechanism by a brushless motor. A failure detection means for detecting a failure of the rotation angle sensor of the rudder angle sensor, pinion sensor and brushless motor;
When the rotation angle θ _{S of the} brushless motor, the rotation angle θ _{h of the} handle detected from the steering angle sensor, and the rotation angle θ _{P of the} pinion detected from the pinion sensor do not satisfy the following relational expression: 2. The vehicle steering apparatus according to claim 1, wherein the failure detection unit detects a failure of at least one of the steering angle sensor, the pinion sensor, and the rotation angle sensor of the brushless motor. 3.
a · θ _h = b · θ _S + c · θ _P
However, a, b, and c are constants. Comprising sensor output detecting means for detecting the output of the rudder angle sensor;
2. The control device according to claim 1, wherein when the sensor output detection unit detects that the steering wheel is in a state close to a handle lock, the control unit stops the rotation operation of the brushless motor. The vehicle steering device according to 2. Comprising drive control means for controlling the drive of the steering motor and the reaction force motor;
When the steering wheel is stationary, the control means performs position control to stop the rotation operation of the brushless motor, and the drive control means controls the driving of the steering motor and the reaction force motor to steer the wheel. The vehicle steering apparatus according to claim 3.

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