Vehicle control system

Abstract

The present invention provides a vehicle control device capable of determining if a drive shaft connected to a wheel has twisted. [Solution] When the rotation of the rotating member connected to the drive shaft is prohibited by the parking lock mechanism (Yes in step S1), the braking torque applied to the wheels by the braking device is less than or equal to a predetermined torque, and the tilt angle in the pitching direction of the vehicle is greater than or equal to a predetermined angle (Yes in step S3), it is determined that the drive shaft is twisted (step S4), and when the rotation of the rotating member by the parking lock mechanism is enabled, an assist torque opposite to the twisting direction of the drive shaft is output from the motor.

Description

Technical Field

[0001] The present invention relates to a vehicle control device capable of locking a drive shaft by a parking lock mechanism.

Background Art

[0002] Patent Documents 1 to 3 describe a vehicle control device provided with a parking lock mechanism configured to prohibit rotation of a drive shaft connected to a wheel by engaging a parking gear interlocked with the wheel and a parking pole, and to enable rotation of the drive shaft by releasing the engagement.

[0003] In the parking lock mechanism described in Patent Document 1, a shift lever operated by a driver and a parking pole are mechanically connected. Therefore, when the load acting on the meshing surface between the parking gear and the parking pole is large, the operating force of the shift lever required to release the meshing increases. Therefore, the control device described in Patent Document 1 is configured to reduce the meshing load between the parking lock gear and the parking pole by driving a motor as a driving force source of the vehicle when the inclination angle in the longitudinal direction of the vehicle is a predetermined angle or more.

[0004] In addition, the vehicle described in Patent Document 2 includes a foot brake device that applies a braking force to the wheels by operating in response to a driver's depression operation of a brake pedal, and an electric parking brake that continuously applies a braking force to the wheels by operating in conjunction with the parking lock mechanism, in addition to the parking lock mechanism. And the control device described in Patent Document 2 is configured to continuously apply a braking force to the wheels by the foot brake device even if the driver's depression operation of the brake pedal is released during the period from when a shift operation for selecting a parking position is performed until a braking force is applied to the wheels by the electric parking brake when the road surface gradient angle is a predetermined angle or more.

[0005] The parking lock mechanism described in Patent Document 3 is configured to lock the rotation of the front drive shaft connected to the front wheel, and the control device is configured to suppress the occurrence of shock when the lock on the front drive shaft is released by the parking lock mechanism. Specifically, the vehicle described in Patent Document 3 further comprises a front motor connected to the front drive shaft and a rear motor connected to the rear drive shaft, and the control device is configured to calculate the amount of torsion of the front drive shaft based on the change in the rotation angle of the front motor and the change in the rotation angle of the rear motor from the time the front drive shaft is locked by the parking lock mechanism and from the time the braking force applied to the wheel is released, and to output a torque from the front motor corresponding to that amount of torsion. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Patent No. 3454009 [Patent Document 2] Japanese Patent Publication No. 2020-100312 [Patent Document 3] Japanese Patent Publication No. 2015-027134 [Overview of the project] [Problems that the invention aims to solve]

[0007] The control device described in Patent Document 1 is configured to release the parking lock when the vehicle is parked on a slope, by driving a motor as a driving force source to reduce the meshing load between the parking lock gear and the parking pawl, which increases when the vehicle is parked on a slope. On the other hand, the magnitude of the torque acting on the drive shaft connected to the wheel differs depending on whether braking torque is applied to the wheel, and the time between the parking lock being engaged and the application of braking torque to the wheel. In other words, the meshing load acting on the parking lock gear and the parking pawl may not be determined solely by the slope angle of the road surface. Therefore, if the meshing load acting on the parking lock gear and the parking pawl is smaller than the load determined based on the slope angle of the road surface, outputting a torque determined according to that slope angle from the motor may result in excessive motor output torque.

[0008] Furthermore, the control device described in Patent Document 2 is configured to prevent the drive shaft from twisting by applying braking torque to the wheels via the foot brake device until the braking torque from the electric parking brake acts on the wheels. In other words, when the parking lock is engaged, the device is configured to constantly apply braking torque to the wheels. However, if the electric parking brake cannot be activated, or if there is no electric parking brake, or if the control device does not have a function to apply braking torque to the wheels via the foot brake device until the braking torque from the electric parking brake acts on the wheels, the drive shaft may twist. The control device described in Patent Document 2 does not have a function to determine if the drive shaft has twisted in this way, so it cannot properly determine if the drive shaft has twisted, and the vehicle may vibrate when the parking lock mechanism is released and the twist of the drive shaft is eliminated.

[0009] The control device described in Patent Document 3 determines the amount of torsion of the front drive shaft based on the change in the rotation angle of the front motor and the change in the rotation angle of the rear motor. Therefore, in the case of a vehicle in which a motor is connected to only one of the front or rear wheels, such as a front-drive or rear-drive two-wheel drive vehicle, it may not be possible to determine if the drive shaft has torn, thus limiting the types of vehicles in which it is possible to determine if the drive shaft has torn.

[0010] This invention was made in view of the above-mentioned technical problems, and the object of this invention is to provide a vehicle control device that can determine if a drive shaft connected to a wheel has twisted. [Means for solving the problem]

[0011] To achieve the above objective, this invention provides a vehicle control device comprising: a drive shaft with one end connected to a wheel; a motor capable of transmitting torque to the drive shaft; a parking lock mechanism capable of selectively switching between a locked state in which the rotation of a predetermined rotating member between the motor and the drive shaft is prohibited and an unlocked state in which the predetermined rotating member is rotatable; and a braking device that applies braking torque to the wheel, wherein the device includes a controller for controlling the motor, the controller having a parking determination unit that determines whether the rotation of the rotating member is prohibited by the parking lock mechanism, and a determination that the braking torque applied to the wheel by the braking device is less than or equal to a predetermined torque. The system is characterized by comprising: a brake determination unit that makes a determination; an inclination angle determination unit that determines whether the inclination angle of the vehicle in the pitching direction is greater than or equal to a predetermined angle; a torsion determination unit that determines whether the drive shaft is twisted when the rotation of the rotating member is prohibited by the parking lock mechanism, the braking torque applied to the wheel by the braking device is less than or equal to the predetermined torque, and the inclination angle is greater than or equal to the predetermined angle; and a motor control unit that outputs an assist torque from the motor in the direction of the torsion of the drive shaft when it is determined that the drive shaft is twisted when the rotation of the rotating member is enabled by the parking lock mechanism.

[0012] Furthermore, in this invention, the twist determination unit may determine that the drive shaft is twisted if the rotation of the rotating member is prohibited by the parking lock mechanism and the braking torque applied to the wheel by the braking device is less than or equal to the predetermined torque for a predetermined period of time or longer.

[0013] Furthermore, in this invention, the predetermined time may be set to be shorter as the inclination angle increases.

[0014] Furthermore, this invention further includes a wheel speed detection unit for detecting the rotational speed of the wheel, and the twist determination unit may determine that the drive shaft is twisted if the rotational speed of the wheel after the rotation of the rotating member is prohibited by the parking lock mechanism is equal to or greater than a predetermined speed.

[0015] Furthermore, this invention further includes an acceleration detection unit for detecting the acceleration of the vehicle in the longitudinal direction, and the torsion determination unit may determine that the drive shaft is torsion if the difference between the maximum and minimum values ​​of the acceleration since the rotation of the rotating member has been prohibited by the parking lock mechanism is greater than or equal to a predetermined difference.

[0016] Furthermore, this invention relates to a vehicle control device comprising a drive shaft with one end connected to a wheel, a motor capable of transmitting torque to the drive shaft, and a parking lock mechanism capable of selectively switching between a locked state in which the rotation of a predetermined rotating member between the motor and the drive shaft is prohibited and an unlocked state in which the predetermined rotating member is rotatable, the control device further comprising a wheel speed detection unit for detecting the rotational speed of the wheel, and a controller for controlling the motor, wherein the controller includes a parking determination unit for determining that the rotation of the rotating member is prohibited by the parking lock mechanism, and an inclination angle determination unit for determining that the inclination angle of the vehicle in the pitching direction is greater than or equal to a predetermined angle, The device is characterized by comprising: a rotation speed determination unit that determines whether the rotation speed of the wheel is equal to or greater than a predetermined speed; a twist determination unit that determines whether the drive shaft is twisted when the rotation of the rotating member is prohibited by the parking lock mechanism, the inclination angle is equal to or greater than the predetermined angle, and the rotation speed of the wheel after the rotation of the rotating member has been prohibited by the parking lock mechanism is equal to or greater than the predetermined speed; and a motor control unit that outputs an assist torque from the motor in the direction of the twist of the drive shaft when it is determined that the drive shaft is twisted when the rotation of the rotating member is enabled by the parking lock mechanism.

[0017] Furthermore, this invention relates to a vehicle control device comprising a drive shaft with one end connected to a wheel, a motor capable of transmitting torque to the drive shaft, and a parking lock mechanism capable of selectively switching between a locked state in which the rotation of a predetermined rotating member between the motor and the drive shaft is prohibited and an unlocked state in which the predetermined rotating member is rotatable, wherein the control device further comprises an acceleration detection unit for detecting the acceleration of the vehicle in the longitudinal direction and a controller for controlling the motor, the controller comprising a parking determination unit for determining that the rotation of the rotating member is prohibited by the parking lock mechanism, and a parking determination unit for determining that the tilt angle of the vehicle in the pitching direction is greater than or equal to a predetermined angle. The device is characterized by comprising: an inclination angle determination unit that determines that; a torsion determination unit that determines that the drive shaft is torn when the rotation of the rotating member is prohibited by the parking lock mechanism, the inclination angle is greater than or equal to the predetermined angle, and the difference between the maximum and minimum values ​​of the acceleration since the rotation of the rotating member was prohibited by the parking lock mechanism is greater than or equal to a predetermined difference; and a motor control unit that outputs an assist torque from the motor in the direction of the torsion of the drive shaft when it is determined that the drive shaft is torn when the rotation of the rotating member is enabled by the parking lock mechanism.

[0018] Furthermore, in this invention, the controller further includes an abnormality determination unit that determines whether the braking torque applied to the wheel by the braking device cannot be controlled, and when it is determined that the braking torque applied to the wheel by the braking device cannot be controlled, the torsion determination unit does not need to determine the torsion of the drive shaft. [Effects of the Invention]

[0019] The vehicle control device in this invention determines that the drive shaft is twisted when the rotation of a predetermined rotating member between the motor and the drive shaft is prohibited by the parking lock mechanism, the braking torque applied to the wheels by the braking device is less than or equal to a predetermined torque, and the tilt angle in the pitching direction of the vehicle is greater than or equal to a predetermined angle. Therefore, when releasing the parking lock mechanism, it is possible to determine whether or not to output assist torque from the motor to counteract the torsional torque accumulated in the drive shaft. As a result, it is possible to suppress vehicle vibration caused by the output of unnecessary assist torque from the motor or the failure to output the necessary assist torque when releasing the parking lock mechanism.

[0020] Furthermore, the vehicle control device in this invention determines that the drive shaft is twisted when the rotation of a predetermined rotating member between the motor and the drive shaft is prohibited by the parking lock mechanism, the tilt angle in the pitching direction of the vehicle is greater than or equal to a predetermined angle, and the rotational speed of the wheels after the rotation of the rotating member is prohibited by the parking lock mechanism is greater than or equal to a predetermined speed.Therefore, it is possible to suppress the determination that the drive shaft is twisted when the wheels are not rotating due to driving resistance or frictional resistance of the rotating member leading to the wheels.As a result, it is possible to suppress the output of assist torque from the motor and the resulting vibration of the vehicle when the parking lock mechanism is released.In other words, it is possible to determine whether or not the drive shaft is twisted based on the actual behavior of the vehicle, and the accuracy of the drive shaft twist determination can be improved.

[0021] Furthermore, in the vehicle control device of this invention, when the rotation of a predetermined rotating member between the motor and the drive shaft is prohibited by the parking lock mechanism, the inclination angle of the vehicle in the pitching direction is equal to or greater than a predetermined angle, and the difference between the maximum value and the minimum value of the acceleration in the longitudinal direction of the vehicle after the rotation of the rotating member is prohibited by the parking lock mechanism is equal to or greater than a predetermined difference, it is determined that the drive shaft is twisted. Therefore, the acceleration in the longitudinal direction of the vehicle and the inclination angle of the vehicle can be obtained based on the signals detected by the acceleration detection unit, and there is no need to provide another sensor for determining the twist of the drive shaft, which can suppress the increase in the size of the vehicle or suppress the complication of the data processing of the sensor.

Brief Description of the Drawings

[0022] [Figure 1] FIG. 1 is a diagram schematically showing an example of a vehicle in an embodiment of this invention. [Figure 2] FIG. 2 is a block diagram for explaining the functional configuration of the controller. [Figure 3] FIG. 3 is a flowchart for explaining a control example of setting a twist determination flag based on the inclination angle, EPB, and brake device. [Figure 4] FIG. 4 is a flowchart for explaining a control example of setting the non-braking state and the braking state of the EPB. [Figure 5] FIG. 5 is a flowchart for explaining a control example of setting a twist determination flag based on the time after the EPB and the brake device become non-braking states. [Figure 6] FIG. 6 is a time chart for explaining an example of changes in the inclination angle, travel range, presence or absence of a brake operation, control state of the EPB, EPB holding force determination counter, presence or absence of braking torque by the EPB, twist determination counter, and twist determination flag when the non-braking state and the braking state of the EPB are determined based on the control example shown in FIG. 4 and the twist determination flag is set based on the control example shown in FIG. 5. [Figure 7]Figure 7 is a flowchart illustrating a control example that sets a torsion detection flag based on wheel speed. [Figure 8] Figure 8 shows the relationship between torsional torque and the difference between the maximum and minimum values ​​of the vehicle's longitudinal acceleration. [Figure 9] Figure 9 is a flowchart illustrating a control example in which a torsion detection flag is set based on the difference between the maximum and minimum values ​​of the vehicle's longitudinal acceleration. [Figure 10] Figure 10 is a flowchart illustrating a control example for setting a control prohibition judgment flag. [Modes for carrying out the invention]

[0023] This invention will be described based on the embodiments shown in the figures. The embodiments described below are merely examples of how this invention can be implemented and do not limit it.

[0024] An example of a vehicle in this embodiment of the present invention is schematically shown in Figure 1. The vehicle Ve shown in Figure 1 is an electric vehicle equipped with a motor (MG) 1 as a driving force source. The motor 1 can be configured in the same way as motors provided as driving force sources in conventional electric vehicles and hybrid vehicles. That is, in addition to functioning as a motor that generates driving torque by being supplied with power from an energy storage device (not shown), it also functions as a generator that converts at least a portion of the power of the output shaft 2 into electricity by being rotated along with the output shaft 2. Specifically, it is configured as a permanent magnet synchronous motor or an induction motor, etc.

[0025] A first drive gear 3 is attached to the output shaft 2 of motor 1. A first driven gear 4, which meshes with the first drive gear 3 and is formed to be larger in diameter than the first drive gear 3, is attached to an intermediate shaft 5 that is positioned parallel to the output shaft 2 of motor 1. In other words, the first drive gear 3 and the first driven gear 4 constitute a reduction gear pair.

[0026] A second drive gear 6 is further attached to the intermediate shaft 5. A second driven gear 7, which meshes with the second drive gear 6 and is formed to be larger in diameter than the second drive gear 6, is attached to the output shaft 8 of the motor 1, which is arranged parallel to the output shaft 2 and the intermediate shaft 5. In other words, the second drive gear 6 and the second driven gear 7 constitute a reduction gear pair. One end of a drive shaft 9 is connected to the output shaft 8 so as to be able to rotate as a whole, and a wheel 10 is connected to the other end of the drive shaft 9.

[0027] Furthermore, a parking lock mechanism 11 is provided that can selectively switch between a locked state in which the rotation of the intermediate shaft 5 is prohibited and an unlocked state in which the intermediate shaft 5 is rotatable. This parking lock mechanism 11 can be configured in the same way as parking lock mechanisms provided in conventional vehicles. Specifically, the parking lock mechanism 11 consists of a parking lock gear 12 attached to the intermediate shaft 5, a parking pawl 13 that can selectively engage with the parking lock gear 12, and an actuator (not shown) that operates the parking pawl 13. When a parking range is selected by the shift device 24 described later, the parking pawl 13 is rotated by an actuator (not shown) or the like to engage with the parking lock gear 12. By engaging the parking pawl 13 with the parking lock gear 12 in this way, the rotation of the parking lock gear 12 is prohibited. Therefore, the rotation of the drive shaft 9, which is connected to the parking lock gear 12 via the intermediate shaft 5 or the like in a way that allows torque transmission, is prohibited.

[0028] The vehicle Ve shown in Figure 1 is equipped with a brake system 14 that applies braking torque to the wheels 10 in accordance with the amount of operation of a brake pedal (not shown) operated by the driver. This brake system 14 can be configured in the same way as brake systems installed in conventional vehicles. That is, it can be configured as a disc brake that applies braking torque to the wheels 10 by clamping a brake rotor that rotates integrally with the wheels 10 with brake pads, or as a drum brake that applies braking torque to the wheels 10 by pressing brake shoes from the inside of a drum that rotates integrally with the wheels 10. Furthermore, the clamping force of the brake pads and the pressing force of the brake shoes can be controlled by an actuator (not shown) that generates hydraulic or electromagnetic force in accordance with the amount of operation of the brake pedal.

[0029] Furthermore, the vehicle Ve shown in Figure 1 is equipped with an electric parking brake (hereinafter referred to as EPB) 15. This EPB 15 is configured in the same way as an EPB provided in a conventional vehicle, and when a shift operation is performed to select the parking range, the motor 16 is activated, driving a caliper and brake shoe (not shown) to apply braking torque to the wheel 10, and when a driving range other than the parking range is selected, the braking torque is reduced. From the viewpoint of mounting the motor 16, the motor 16 may be mounted on the vehicle body, and a wire or the like that is provided to connect the motor 16 to the caliper and brake shoe, and the caliper and brake shoe may be driven by rotating the motor 16 to wind up the wire. The brake device 14 and EPB 15 described above correspond to the "braking device" in the embodiment of this invention.

[0030] In the example shown in Figure 1, the motor 1, the gear train that transmits torque from the motor 1 to the output shaft 8, and the output shaft 8 are housed in a single case 17, which is connected to the vehicle body 19 via a mount 18. The wheels 10 are also held to the vehicle body 19 via a suspension 20.

[0031] In the vehicle Ve shown in Figure 1, when the brake pedal is operated and the driver performs a shift operation to select the parking range, the vehicle is permitted to switch the driving range to the parking range. When switching to the parking range in this manner, the rotation of the intermediate shaft 5 is prohibited by the parking lock mechanism 11, and braking torque is applied to the wheels 10 by the EPB 15.

[0032] As described above, the time from when the shift operation is performed until the rotation of the intermediate shaft 5 is prohibited by the parking lock mechanism 11 may be shorter than the time until braking torque is applied to the wheels 10 by the EPB 15. Therefore, for example, when parking the vehicle Ve on a slope or when the wheels 10 are parked on top of some object, if the driver reduces the amount of brake pedal operation before braking torque is applied to the wheels 10 by the EPB 15, the wheels 10 will rotate (turn) even though the rotation on the input side of the drive shaft 9 is prohibited. Also, if the EPB 15 cannot be activated for some reason, the wheels 10 will rotate (turn) even though the rotation on the input side of the drive shaft 9 is prohibited after the driver reduces the amount of brake pedal operation. As a result, the drive shaft 9 twists. In other words, torque (hereinafter referred to as torsional torque) corresponding to its elastic modulus and the amount of twist accumulates in the drive shaft 9.

[0033] When the drive shaft 9 is twisted in this manner, and the shift is operated to select a driving range other than the parking range, the twist of the drive shaft 9 is released at the same time that the lock on the intermediate shaft 5 by the parking lock mechanism 11 is released. In other words, the torsional torque accumulated in the drive shaft 9 is transmitted to the motor 1, which is the driving force source. When this twist of the drive shaft 9 is released, the torque pulsates according to the elastic modulus of the drive shaft 9. As a result, the transmission of the pulsating torque to the motor 1 may cause the vehicle Ve to vibrate.

[0034] Furthermore, the pulsation of torque in the drive shaft 9 can cause the suspension 20 to vibrate vertically, and this vibration can be transmitted to the vehicle body 19, potentially causing the vehicle Ve to vibrate.

[0035] Therefore, if the drive shaft 9 is twisted, the motor 1 outputs an assist torque to counteract the torsional torque accumulated in the drive shaft 9, thereby suppressing vibration when the parking lock mechanism 11 is released.

[0036] On the other hand, if the above-mentioned assist torque is output from the motor 1 while the drive shaft 9 is not twisted, the assist torque is not canceled out by the torsional torque, and the assist torque is transmitted to the wheel 10. As a result, the vehicle Ve may actually vibrate.

[0037] Therefore, the vehicle control device in this embodiment of the invention is configured to determine whether or not the drive shaft 9 is twisted, and to output assist torque from the motor 1 if it is determined that the drive shaft 9 is twisted. In the example shown in Figure 1, an electronic control unit (hereinafter referred to as ECU) 21 for controlling the motor 1 is provided. This ECU 21 is mainly composed of a microcomputer and is configured to control the output torque of the motor 1 based on the input signal and a pre-stored calculation formula. This ECU 21 corresponds to the "controller" in this embodiment of the invention.

[0038] In the example shown in Figure 1, the ECU 21 is connected to an acceleration sensor 22 that detects the longitudinal acceleration of the vehicle Ve, a wheel speed sensor 23 that detects the rotational speed (or rotational angle) of the wheels 10, and a shift sensor 25 that detects the driving range selected by the shift device 24, and signals are input from these sensors 22, 23, and 25. In addition, the ECU 21 is connected to an EPB-ECU 26 that controls the EPB 15 and a B-ECU 27 that controls the brake device 14, and signals are input from these ECUs 26 and 27. The acceleration sensor 22 corresponds to the "acceleration detection unit" in this embodiment of the invention, and the wheel speed sensor 23 corresponds to the "wheel speed detection unit" in this embodiment of the invention.

[0039] The above-described shift device 24 may be a so-called momentary type shift device in which, for example, operating the shift lever 28 to a shift position corresponding to the driving range turns on a shift sensor 25 corresponding to that shift position, a signal is input to the ECU 21, and releasing the operation of the shift lever 28 returns the shift lever 28 to a predetermined standby position. The shift device 24 may also be provided with a parking button for selecting a parking range, and the shift sensor 25 may include a sensor that is turned on when the parking button is pressed.

[0040] Furthermore, the EPB-ECU26 is connected to, for example, the shift sensor 25, and based on the signal input from the shift sensor 25, it determines whether or not the EPB 15 is operating, and based on the result of that determination, it outputs a command signal to the ECU21 and the motor 16. In addition, the B-ECU27 receives signals such as the amount of brake pedal depression or pedal force or master cylinder pressure, or signals that detect hydraulic pressure or electromagnetic force to generate braking torque for the brake device 14, and based on these signals, it determines the braking torque to be applied to the brake device 14 or the braking torque that is currently applied to the brake device 14. Then it outputs a signal representing the magnitude of that braking torque to the ECU21.

[0041] Figure 2 shows a block diagram illustrating the functional configuration of the ECU 21. The ECU 21 shown in Figure 2 comprises a parking determination unit 29, a brake determination unit 30, a tilt angle determination unit 31, a twist determination unit 32, a rotation speed determination unit 33, an abnormality determination unit 34, and a motor control unit 35. The parking determination unit 29 determines whether or not the vehicle is in a parking range where the rotation of the intermediate shaft 5 is prohibited by the parking lock mechanism 11, in other words, whether or not the vehicle is in a locked state where the rotation of the intermediate shaft 5 is prohibited. Specifically, it determines whether or not the vehicle is in a parking range based on whether or not a predetermined time has elapsed since the parking range was selected by a shift operation, or based on a command signal to the actuator that operates the parking pole 13.

[0042] The brake determination unit 30 determines whether the braking torque acting on the wheels 10 is less than or equal to a predetermined torque. Specifically, it determines whether the braking torque acting on the wheels 10 is less than or equal to a predetermined torque based on signals input to the ECU 21 from the EPB-ECU 26 or B-ECU 27. The predetermined torque can be set to a braking torque such that the wheels 10 do not rotate when the vehicle Ve is stopped on a road surface at a predetermined angle as defined in the specifications of the vehicle Ve.

[0043] The tilt angle determination unit 31 determines whether the tilt angle of the vehicle Ve in the pitching direction is greater than or equal to a predetermined angle. Specifically, it determines whether the tilt angle of the vehicle Ve is greater than or equal to a predetermined angle based on the longitudinal acceleration of the vehicle Ve detected by the acceleration sensor 22. The predetermined angle can be set to, for example, the tilt angle at which the wheels 10 do not rotate even when no braking torque is applied. In other words, the predetermined angle can be set based on the load acting on the vehicle Ve in the longitudinal direction based on the tilt angle of the vehicle Ve and the vehicle weight, or the rolling friction resistance between the wheels 10 and the road surface.

[0044] The twisting determination unit 32 determines whether or not the drive shaft 9 has twisted by executing each of the control examples described later.

[0045] The rotation speed determination unit 33 determines whether the rotation speed of the wheel 10 is equal to or greater than a predetermined speed. Specifically, it determines the rotation speed of the wheel 10 after the rotation of the intermediate shaft 5 is prohibited by the parking lock mechanism 11, based on the value detected by the wheel speed sensor 23, and determines whether the rotation speed of the wheel 10 is equal to or greater than a predetermined speed. This predetermined speed only needs to be able to determine that the wheel 10 has rotated, and can be determined based on the detection accuracy of the wheel speed sensor 23, etc. The rotation speed of the wheel 10 is determined by differentiating the amount of change in the rotation angle of the wheel 10 detected by the wheel speed sensor 23, and therefore, the determination by the rotation speed determination unit 33 is equivalent to determining whether the amount of change in the rotation angle of the wheel 10 within a predetermined time, such as the control cycle time, is equal to a predetermined amount of change.

[0046] The abnormality detection unit 34 determines whether the braking torque applied to the wheel 10 by the brake device 14 and EPB 15 cannot be controlled, or whether the ECU 21 cannot receive a signal related to that braking torque. Specifically, it determines whether a signal indicating a malfunction in the brake device 14 or EPB 15 has been input to the ECU 21 from the EPB-ECU 26 or B-ECU 27, or whether there is a problem with communication between the EPB-ECU 26 or B-ECU 27 and the ECU 21. In other words, it determines whether the preconditions for the motor 1 to output assist torque have been met. The result of this determination is then output to the torsion detection unit 32.

[0047] When the torsion detection unit 32 determines that the drive shaft 9 is torsion, the motor control unit 35 outputs an assist torque to counteract the torsional torque accumulated in the drive shaft 9 when enabling the rotation of the intermediate shaft 5 by the parking lock mechanism 11.

[0048] Figure 3 shows a flowchart illustrating an example of control for determining whether or not the drive shaft 9 is twisted. In the control example shown in Figure 3, first, it is determined whether or not the parking range is set (step S1). This step S1 can be determined by the parking determination unit 29. Specifically, it can be determined based on whether or not a predetermined time has elapsed since the parking range was selected by a shift operation, or based on a command signal to the actuator that operates the parking pole 13.

[0049] If step S1 is negatively determined because the parking range is not set, the flag indicating that the drive shaft 9 is twisted (hereinafter referred to as the twisting determination flag) is set to off (step S2), that is, it is determined that the drive shaft 9 is not twisted, and this routine is terminated. Conversely, if step S1 is positively determined because the parking range is set, it is determined whether the tilt angle (absolute value) of the vehicle Ve is greater than or equal to a predetermined angle, and whether the EPB 15 and brake device 14 are in a non-braking state (step S3).

[0050] Step S3 is a step to determine whether the conditions for twisting of the drive shaft 9 are met. That is, it determines whether the rotation on the input side of the drive shaft 9 is prohibited while the wheel 10 is able to rotate, or in other words, whether sufficient braking torque is not acting on the wheel 10. This step S3 can be determined by the brake determination unit 30 and the tilt angle determination unit 31 described above.

[0051] If the vehicle Ve's tilt angle (absolute value) is greater than or equal to a predetermined angle, and the EPB 15 and brake device 14 are in a non-braking state, and this is determined to be positive in step S3, then the condition for the drive shaft 9 to twist is met, so the twisting judgment flag is set to ON (step S4), that is, it is determined that the drive shaft 9 is twisted, and this routine is terminated.

[0052] Conversely, if the tilt angle (absolute value) of the vehicle Ve is less than a predetermined angle, or if the EPB 15 is in a braking state, or if the brake device 14 is in a braking state, and a negative determination is made in step S3, the torsion determination flag is maintained (step S5) and this routine is terminated. That is, if the torsion determination flag was set to ON in the previous routine, the torsion determination flag is kept ON, and conversely, if the torsion determination flag was set to OFF in the previous routine, the torsion determination flag is kept OFF.

[0053] This is because, when the parking range is set and the vehicle Ve is stopped, once the drive shaft 9 twists, it is thought that the twist will not be resolved. Specifically, even if the brake device 14 or EPB 15 switches to a locked state (i.e., a state where braking torque is applied) after the drive shaft 9 has twisted, the wheels 10 will only continue to rotate, and the drive shaft 9 will not twist, thus maintaining the twist detection flag.

[0054] As described above, when the parking range is set, that is, when the rotation of the intermediate shaft 5 is prohibited by the parking lock mechanism 11, when the tilt angle of the vehicle Ve is greater than or equal to a predetermined angle, and furthermore, when the brake device 14 and EPB 15 are not braking, it is determined that the drive shaft 9 is twisted. Therefore, when switching from the parking range to another driving range, it is possible to determine whether or not to output assist torque from the motor 1 to counteract the torsional torque accumulated in the drive shaft 9. As a result, when switching from the parking range to another driving range, it is possible to suppress the vibration of the vehicle Ve caused by the output of unnecessary assist torque from the motor 1 or the failure to output the necessary assist torque.

[0055] On the other hand, the EPB15 starts to increase the braking torque applied to the wheels 10 after a predetermined time has elapsed since the motor 16 was energized, but there is no sensor to detect the point in time when this braking torque begins to be applied. Therefore, the EPB15 may determine that it is in a non-braking state if the time elapsed since the motor 16 was energized is less than the predetermined time. An example of this control is shown in Figure 4.

[0056] In the example shown in Figure 4, first, it is determined whether the EPB 15 has switched from a release state, where it is not braking and the motor 16 is not energized, to a transition state, where the motor 16 is energized in order to apply braking torque to the wheel 10 (step S11). This step S11 is a step to determine whether the EPB 15 has been activated in order to apply braking torque to the wheel 10. Therefore, the determination can be made based on whether or not the motor 16 has been energized in order to begin applying braking torque to the wheel 10.

[0057] If step S11 is positively determined because the EPB15 has switched from the released state to the transition state, in other words, because power has started to be supplied to the motor 16, the EPB holding force determination counter is set to "0" (step S12). On the other hand, if step S11 is negatively determined because the EPB15 is in the released state, or in the transition state, or in the locked state with the wheel 10 locked, and it is not the timing of a switch from the released state to the transition state, the EPB holding force determination counter is increased (step S13). In other words, the EPB holding force determination counter is reset at the timing when the EPB15 switches from the released state to the transition state, and in all other states, the EPB holding force determination counter is increased. Note that it is sufficient to measure the time from when the EPB15 starts to operate until braking torque begins to act on the wheel 10, and the EPB holding force determination counter may have an upper limit that is longer than the measured time.

[0058] Following steps S12 and S13, it is determined whether at least one of the following conditions is met: a first condition that the EPB 15 is in a released state, and a second condition that the EPB 15 is in a transition state and the EPB holding force determination counter is less than or equal to a predetermined value. Step S14 is a step to determine whether the EPB 15 is in a non-braking state. Therefore, the time from when the motor 16 is energized to apply braking torque to the wheel 10 by the EPB 15 until the EPB 15 begins to apply braking torque to the wheel 10 can be determined in advance by experimentation or simulation, and this time can be set as the predetermined value in step S14.

[0059] If step S14 is positively determined because EPB15 is in a released state, or EPB15 is in a transition state and the EPB holding force determination counter is below a predetermined value, then it is determined that EPB15 is in a non-braking state (step S15), and this routine is terminated. Conversely, if step S14 is negatively determined because neither the first nor the second condition in step S14 is met, then it is determined that EPB15 is in a braking state (step S16), and this routine is terminated.

[0060] As described above, by counting the elapsed time since the motor 16 was energized to begin applying braking torque to the wheel 10, and determining whether the EPB 15 is in a non-braking state based on that elapsed time, it is possible to determine the period during which braking torque is not applied to the wheel 10 and the period during which braking torque is applied to the wheel 10 during the transition period when the EPB 15 switches from the released state to the locked state. As a result, it is possible to accurately determine whether the conditions for twisting of the drive shaft 9 are met.

[0061] Furthermore, the amount of twist in the drive shaft 9 gradually increases after the braking torque is no longer applied to the wheel 10. In other words, if the elapsed time since the braking torque was no longer applied to the wheel 10 is short, the amount of twist in the drive shaft 9 is small, and outputting assist torque from the motor 1 may actually cause vibration. For this reason, it is also possible to determine whether or not the drive shaft 9 has twisted depending on the elapsed time since the braking torque was applied to the wheel 10. In other words, the twisting determination flag may be switched on when the drive shaft 9 has twisted to the extent that it is necessary to output assist torque from the motor 1 to suppress the shock that occurs when the parking lock mechanism 11 is released.

[0062] A flowchart illustrating an example of this control is shown in Figure 5. In the control example shown in Figure 5, similar to steps S1 and S2 in the control example shown in Figure 3, it is determined whether or not the parking range is set (step S21). If the determination in step S21 is negative because the parking range is not set, the twist detection flag is set to off (step S22), and this routine is terminated. If the twist detection flag is set to off, the twist detection counter, which will be described later, is set to "0".

[0063] Conversely, if a positive determination is made in step S21 due to the setting of a parking range, it is determined whether the EPB 15 and brake device 14 are in a non-braking state (step S23). This step S23 can be determined by the brake determination unit 30 and the tilt angle determination unit 31, similar to step S3 in the control example shown in Figure 3. Alternatively, it can be determined whether the EPB 15 is in a non-braking state based on the control example shown in Figure 4.

[0064] If the determination in step S23 is positive because the EPB15 and brake device 14 are not braking, the amount of torsion of the drive shaft 9 may increase. Therefore, if the determination in step S23 is positive, the torsion determination counter for determining whether or not the drive shaft 9 has torn is increased (step S24). Conversely, if the determination in step S23 is negative because at least one of the EPB15 and brake device 14 is applying braking torque to the wheel 10, the torsion determination counter is maintained (step S25).

[0065] Following steps S24 and S25, it is determined whether the inclination angle (absolute value) of the vehicle Ve is greater than or equal to a predetermined angle and whether the torsion judgment counter is greater than or equal to a predetermined value (step S26). Step S26 is a step to determine whether the conditions for the drive shaft 9 to twist are met, and the predetermined angle can be set to the same angle as in step S3 in the control example shown in Figure 3.

[0066] Furthermore, the predetermined value in step S26 is the time required for the drive shaft 9 to twist to the point where the motor 1 needs to output assist torque when releasing the parking lock mechanism 11, and is determined by conducting experiments or simulations. Since the rate of change of the drive shaft 9's twist amount is thought to differ depending on the vehicle Ve's tilt angle, the predetermined value in step S26 may be a variable number set to decrease as the vehicle Ve's tilt angle increases.

[0067] If the tilt angle of vehicle Ve is greater than or equal to a predetermined angle, and the twist detection counter is greater than or equal to a predetermined value, a positive determination is made in step S26, the twist detection flag is set to ON (step S27), and this routine is terminated. Conversely, if the tilt angle of vehicle Ve is less than a predetermined angle, or the twist detection counter is less than a predetermined value, and a negative determination is made in step S26, the twist detection flag is maintained (step S28), and this routine is terminated.

[0068] Figure 6 shows a time chart illustrating an example of changes in the vehicle Ve tilt angle, driving range, presence or absence of brake operation, EPB15 control state, EPB holding force determination counter, presence or absence of braking torque by EPB15, torsion determination counter, and torsion determination flag when the non-braking and braking states of EPB15 are determined based on the control example shown in Figure 4, and when the torsion determination flag is set based on the control example shown in Figure 5.

[0069] At time t0 in Figure 6, the inclination angle of the vehicle Ve is greater than or equal to the predetermined angle. At that time, because the driving range is the drive range (D range), the brakes are applied, and conversely, the EPB15 is in the released state. In this case, braking torque is applied to the wheels 10 after the vehicle Ve has stopped, and since the upstream side (motor 1 side) of the drive shaft 9 is rotatable, no twisting occurs in the drive shaft 9.

[0070] At time t1, the gear shift has been performed and the vehicle is in parking range. Therefore, a positive judgment is made in step S21 in Figure 5. On the other hand, at time t1, the brakes have been applied, so the brake device 14 is applying braking torque to the wheels 10. Therefore, a negative judgment is made in step S23. Consequently, the torsion judgment counter remains unchanged, that is, it is maintained at "0".

[0071] Furthermore, when the vehicle is switched to the parking range, power is supplied to the motor 16 at time t2 to activate the EPB 15. In other words, the control state of the EPB 15 switches from the release state to the transition state. Therefore, a positive judgment is made in step S11 in Figure 4, and the EPB holding force judgment counter is set to "0".

[0072] In the example shown in Figure 6, the brake operation is released at time t3. That is, the braking torque applied to the wheel 10 by the brake device 14 decreases. At this time t3, the EPB holding force determination counter is below a predetermined value, so a positive judgment is made in step S14 in Figure 4, and the EPB 15 is determined to be in an unbraked state. Therefore, a positive judgment is made in step S23 in Figure 5, and the torsion determination counter begins to increase.

[0073] Then, at time t4, the torsion detection counter exceeds a predetermined value, resulting in a positive determination in step S26 in Figure 5. As a result, the torsion detection flag is switched to ON at time t4.

[0074] In the example shown in Figure 6, at time t5, the EPB holding force determination counter becomes larger than a predetermined value, indicating that the EPB 15 is in a braking state, and the EPB holding force determination counter is maintained at a constant value. Furthermore, at time t6, the EPB 15 switches to a locked state.

[0075] As described above, the time during which no braking torque is acting on the wheel 10 is counted, and based on that time, it is determined whether or not the drive shaft 9 has twisted. Therefore, for example, if the amount of twisting of the drive shaft 9 is small, such as when braking torque is applied to the wheel 10 by the EPB 15 slightly later than when braking torque is no longer applied to the wheel 10 by the brake device 14, it is possible to suppress the turning on of the twisting detection flag. As a result, it is possible to suppress the vibration of the vehicle Ve caused by the output of assist torque from the motor 1 when releasing the parking lock mechanism 11.

[0076] In the control example shown in Figure 3, the determination of whether the drive shaft 9 has twisted is made on the condition that the brake device 14 and EPB 15 are not applying braking torque to the wheel 10. On the other hand, since the drive shaft 9 twists when the wheel 10 rotates, the determination may also be made based on whether the wheel 10 has rotated (went around). That is, instead of step S3 in Figure 3, it may be determined whether the tilt angle (absolute value) of the vehicle Ve is greater than or equal to a predetermined angle, and whether the rotational speed (wheel speed) of the wheel 10 detected by the wheel speed sensor 23 is greater than or equal to a predetermined speed.

[0077] Furthermore, the torsion detection flag may be set to ON if all conditions are met, including step S3 in Figure 3, step S26 in Figure 5, and the wheel speed being above a predetermined speed. Figure 7 shows a flowchart illustrating an example of this control, and steps similar to those in Figure 5 are denoted by the same reference numerals and their explanations are omitted.

[0078] In the control example shown in Figure 7, after the torsion detection counter is increased (step S24) or maintained (step S25), it is determined whether the tilt angle (absolute value) of the vehicle Ve is greater than or equal to a predetermined angle, whether the torsion detection counter is greater than or equal to a predetermined value, and whether the wheel speed is greater than or equal to a predetermined speed (step S31).

[0079] If all conditions in step S31 are met and the result is positive, proceed to step S27 and set the twist detection flag to ON. Conversely, if any of the conditions in step S31 are not met and the result is negative, proceed to step S28 and set the twist detection flag to OFF.

[0080] As described above, by determining that the drive shaft 9 is twisted when the wheel speed is above a predetermined speed, it is possible to suppress the determination that the drive shaft 9 is twisted when the wheel 10 is not rotating due to, for example, running resistance or frictional resistance of the rotating members leading to the wheel 10. As a result, it is possible to suppress the vibration of the vehicle Ve caused by the output of assist torque from the motor 1 when releasing the parking lock mechanism 11. In other words, it is possible to determine whether or not the drive shaft 9 is twisted based on the actual behavior of the vehicle Ve, and the accuracy of the determination of drive shaft 9 twisting can be improved.

[0081] Furthermore, a reaction torque is generated in proportion to the elastic modulus of the drive shaft 9 to counteract the torsional torque caused by the twisting of the drive shaft 9. Therefore, when the drive shaft 9 twists, the vehicle Ve vibrates in the longitudinal direction. There is a correlation between the difference between the maximum and minimum values ​​of the longitudinal acceleration and the amount of twist of the drive shaft 9. Figure 8 shows experimental results for determining the relationship between the difference between the maximum and minimum values ​​of the longitudinal acceleration after the rotation of the intermediate shaft 5 is prohibited by the parking lock mechanism 11 and the torsional torque (i.e., amount of twist) of the drive shaft 9. In Figure 8, the horizontal axis represents the torsional torque of the drive shaft 9, i.e., the amount of twist of the drive shaft 9, and the vertical axis represents the difference between the maximum and minimum values ​​of the longitudinal acceleration of the vehicle Ve. Experimental values ​​obtained for the difference between the maximum and minimum values ​​of the longitudinal acceleration with respect to the torsional torque are plotted, and their approximate values ​​are shown as straight lines.

[0082] As shown in Figure 8, it can be seen that as the amount of torsion of the drive shaft 9 increases, the difference between the maximum and minimum values ​​of the longitudinal acceleration after the intermediate shaft 5 is locked by the parking lock mechanism 11 increases. Furthermore, after the intermediate shaft 5 is locked by the parking lock mechanism 11, the amplitude of the longitudinal acceleration gradually decreases. In other words, the amplitude of the first cycle after the intermediate shaft 5 is locked by the parking lock mechanism 11 is the maximum and minimum value.

[0083] Therefore, in this embodiment of the invention, the vehicle control device may determine whether or not the drive shaft 9 has twisted based on the difference between the maximum and minimum values ​​of the longitudinal acceleration of the vehicle Ve after the intermediate shaft 5 has been locked by the parking lock mechanism 11. Figure 9 shows a flowchart illustrating an example of this control. Steps identical to those in the control example shown in Figure 3 are given the same step numbers and their explanations are omitted.

[0084] In the control example shown in Figure 9, if a positive result is obtained in step S1 because the parking range is set, it is determined in step S41 whether the tilt angle (absolute value) of the vehicle Ve is greater than or equal to a predetermined angle, whether the EPB 15 and brake device 14 are in a non-braking state, and whether the difference between the maximum and minimum values ​​of the longitudinal acceleration of the vehicle Ve (Gp-p) is greater than or equal to a predetermined value. The predetermined value in step S41 can be determined based on the magnitude (amplitude) of vibration that the driver finds unnatural when the parking lock mechanism 11 is released. The longitudinal acceleration of the vehicle Ve can be detected by the acceleration sensor 22.

[0085] If step S41 is positively determined because the vehicle Ve's tilt angle (absolute value) is greater than or equal to a predetermined angle, the EPB15 and brake device 14 are in a non-braking state, and the difference between the maximum and minimum values ​​of the vehicle Ve's longitudinal acceleration is greater than or equal to a predetermined value, the torsion determination flag is set to ON (step S4), and this routine is terminated. Conversely, if step S41 is negatively determined because the vehicle Ve's tilt angle (absolute value) is less than a predetermined angle, or the EPB15 is in a braking state, or the brake device 14 is in a braking state, or the difference between the maximum and minimum values ​​of the vehicle Ve's longitudinal acceleration is less than a predetermined value, the torsion determination flag is maintained (step S5), and this routine is terminated.

[0086] Furthermore, the determination in step S31 in Figure 7 may be amended to include a determination of whether the difference between the maximum and minimum values ​​of the longitudinal acceleration of the vehicle Ve is greater than or equal to a predetermined value, or the determination of whether the wheel speed in step S31 is greater than or equal to a predetermined speed may be replaced with a determination of whether the difference between the maximum and minimum values ​​of the longitudinal acceleration of the vehicle Ve is greater than or equal to a predetermined value.

[0087] As described above, whether or not the drive shaft 9 has twisted is determined based on the longitudinal acceleration of the vehicle Ve. This longitudinal acceleration can be determined based on the signal from the acceleration sensor 22 that detects the tilt angle of the vehicle Ve. In other words, the tilt angle of the vehicle Ve and the longitudinal acceleration for determining the twist of the drive shaft 9 can be determined from the signal detected by the acceleration sensor 22. As a result, there is no need to provide other sensors to determine the twist of the drive shaft 9, which can suppress the increase in the size of the vehicle Ve or the complexity of sensor data processing.

[0088] Furthermore, the vehicle control device in this embodiment of the invention is configured not to determine whether the drive shaft 9 is twisted if the brake device 14 fails, or if there is an abnormality in communication between B-ECU27 and ECU21, or if the EPB 15 fails, or if there is an abnormality in communication between EPB-ECU26 and ECU21. Specifically, if any of the above failures or communication failures occur, the control prohibition determination flag is switched to ON, and if the control prohibition determination flag is ON, the twist determination flag is set to OFF.

[0089] Figure 10 shows a flowchart illustrating an example of control for setting a control prohibition judgment flag. In the control example shown in Figure 10, first, it is determined whether the brake device 14 has failed or whether there is an abnormality in communication between B-ECU27 and ECU21, or whether the EPB 15 has failed or whether there is an abnormality in communication between EPB-ECU26 and ECU21 (step S51). This step S51 can be performed by the abnormality determination unit 34. That is, it is determined whether a signal indicating a malfunction in the brake device 14 or EPB 15 has been input to ECU21 from EPB-ECU26 or B-ECU27, or whether communication between EPB-ECU26 or B-ECU27 and ECU21 is not possible.

[0090] If step S51 is positively determined due to a failure in at least one of the brake device 14 and EPB 15, or due to an abnormality in communication between B-ECU 27 or EPB-ECU 26 and ECU 21, the control prohibition determination flag is set to ON (step S52) and this routine is terminated. Conversely, if step S51 is negatively determined due to the brake device 14 and EPB 15 being normal and communication between B-ECU 27 and EPB-ECU 26 and ECU 21 being normal, the control prohibition determination flag is set to OFF (step S53) and this routine is terminated.

[0091] In addition, in steps S1 in Figure 3, S21 in Figure 5, S21 in Figure 7, and S1 in Figure 9, it is determined in step S53 whether the control prohibition judgment flag is set to off. If the control prohibition judgment flag is on and a negative determination is made in those steps, the twist judgment flag is set to off.

[0092] As described above, if the brake device 14 or EPB 15 malfunctions, or if there is an abnormality in communication between B-ECU 27 or EPB-ECU 26 and ECU 21, that is, if the brake device 14 or EPB 15 cannot properly apply braking torque to the wheel 10, or if the brake device 14 or EPB 15 cannot determine the braking torque being applied to the wheel 10, the torsion detection flag is set to off. By setting the torsion detection flag to off in this way and suppressing the output of assist torque from the motor 1, the occurrence of unintended vibrations can be suppressed.

[0093] Furthermore, the vehicle in this embodiment of the invention is not limited to a vehicle in which a motor is connected to each wheel, but may also be a vehicle configured to transmit torque from a single motor to a pair of front wheels or rear wheels, or to all wheels. In addition, it may be a hybrid vehicle equipped with an engine as a driving force source in addition to the motor.

[0094] Furthermore, the configuration connecting the motor 1 and the drive shaft 9, and the rotating member whose rotation is prohibited by the parking lock mechanism 11, are not limited to those shown in Figure 1. Moreover, the vehicle in this embodiment of the invention does not need to be equipped with an EPB 15. In that case, a torsional determination flag can be set based on whether or not the brake device 14 is applying braking torque to the wheel 10. [Explanation of symbols]

[0095] 1,16 motor 2.8 Output shaft 3.6 drive gear 4.7 Driven gear 5 Intermediate axis 9 Drive shaft 10 wheels 11 Parking lock mechanism 12 Parking lock gear 13 Parking poles 14 Brake system 15. Electric Parking Brake (EPB) 17 cases 18 Mount 19 car bodies 20 Suspension 21 Electronic Control Unit (ECU) 22 Accelerometer 23 Wheel speed sensor 24 Shift device 25 Shift Sensor 26 EPB-ECU 27 B-ECU 28 Shift lever 29 Parking determination unit 30 Brake detection unit 31 Inclination angle determination section 32. Torsion detection unit 33 Rotation speed determination unit 34 Abnormality determination section 35 Motor control unit Vehicle

Claims

1. A vehicle control device comprising: a drive shaft with one end connected to a wheel; a motor capable of transmitting torque to the drive shaft; a parking lock mechanism capable of selectively switching between a locked state in which the rotation of a predetermined rotating member between the motor and the drive shaft is prohibited and an unlocked state in which the predetermined rotating member is rotatable; and a braking device that applies braking torque to the wheel, The motor is equipped with a controller that controls the motor, The aforementioned controller, A parking determination unit that determines that the rotation of the rotating member is prohibited by the parking lock mechanism, A brake determination unit that determines whether the braking torque applied to the wheel by the braking device is less than or equal to a predetermined torque, An inclination angle determination unit that determines whether the inclination angle of the vehicle in the pitching direction is greater than or equal to a predetermined angle, A torsion determination unit determines that the drive shaft is torn when the rotation of the rotating member is prohibited by the parking lock mechanism, the braking torque applied to the wheel by the braking device is less than or equal to the predetermined torque, and the inclination angle is greater than or equal to the predetermined angle, The system is configured as follows: When the rotation of the rotating member is enabled by the parking lock mechanism, if it is determined that the drive shaft is twisted, the motor control unit outputs an assist torque from the motor that is opposite to the twisting direction of the drive shaft. A vehicle control device characterized by the following features.

2. A vehicle control device according to claim 1, The twist detection unit determines that the drive shaft is twisted if the rotation of the rotating member is prohibited by the parking lock mechanism and the braking torque applied to the wheel by the braking device is less than or equal to the predetermined torque for a predetermined period of time or longer. A vehicle control device characterized by the following features.

3. A vehicle control device according to claim 2, The predetermined time is set to be shorter the greater the inclination angle. A control device for a vehicle characterized by the following features.

4. A vehicle control device according to claim 1, The system further includes a wheel speed detection unit for detecting the rotational speed of the wheel, The twist detection unit determines that the drive shaft is twisted if the rotation speed of the wheel after the rotation of the rotating member is prohibited by the parking lock mechanism is equal to or greater than a predetermined speed. A vehicle control device characterized by the following features.

5. A vehicle control device according to claim 1, The vehicle further comprises an acceleration detection unit for detecting acceleration in the longitudinal direction, The twist detection unit determines that the drive shaft is twisted if the difference between the maximum and minimum values ​​of the acceleration since the rotation of the rotating member was prohibited by the parking lock mechanism is greater than or equal to a predetermined difference. A vehicle control device characterized by the following features.

6. A vehicle control device comprising: a drive shaft with one end connected to a wheel; a motor capable of transmitting torque to the drive shaft; and a parking lock mechanism capable of selectively switching between a locked state in which the rotation of a predetermined rotating member between the motor and the drive shaft is prohibited and an unlocked state in which the predetermined rotating member is rotatable, A wheel speed detection unit for detecting the rotational speed of the wheel, The system further comprises a controller for controlling the motor, The aforementioned controller, A parking determination unit that determines that the rotation of the rotating member is prohibited by the parking lock mechanism, An inclination angle determination unit that determines whether the inclination angle of the vehicle in the pitching direction is greater than or equal to a predetermined angle, A rotation speed determination unit that determines whether the rotation speed of the wheel is equal to or greater than a predetermined speed, A torsion determination unit determines that the drive shaft is torn when the rotation of the rotating member is prohibited by the parking lock mechanism, the inclination angle is greater than or equal to the predetermined angle, and the rotation speed of the wheel after the rotation of the rotating member is prohibited by the parking lock mechanism is greater than or equal to the predetermined speed. The system is configured as follows: When the rotation of the rotating member is enabled by the parking lock mechanism, if it is determined that the drive shaft is twisted, the motor control unit outputs an assist torque from the motor that is opposite to the twisting direction of the drive shaft. A vehicle control device characterized by the following features.

7. A vehicle control device comprising: a drive shaft with one end connected to a wheel; a motor capable of transmitting torque to the drive shaft; and a parking lock mechanism capable of selectively switching between a locked state in which the rotation of a predetermined rotating member between the motor and the drive shaft is prohibited and an unlocked state in which the predetermined rotating member is rotatable, An acceleration detection unit for detecting the acceleration of the vehicle in the longitudinal direction, The system further comprises a controller for controlling the motor, The aforementioned controller, A parking determination unit that determines that the rotation of the rotating member is prohibited by the parking lock mechanism, An inclination angle determination unit that determines whether the inclination angle of the vehicle in the pitching direction is greater than or equal to a predetermined angle, A torsion determination unit determines that the drive shaft is torn when the rotation of the rotating member is prohibited by the parking lock mechanism, the inclination angle is greater than or equal to the predetermined angle, and the difference between the maximum and minimum values ​​of the acceleration since the rotation of the rotating member was prohibited by the parking lock mechanism is greater than or equal to a predetermined difference. The system is configured as follows: When the rotation of the rotating member is enabled by the parking lock mechanism, if it is determined that the drive shaft is twisted, the motor control unit outputs an assist torque from the motor that is opposite to the twisting direction of the drive shaft. A vehicle control device characterized by the following features.

8. A vehicle control device according to any one of claims 1 to 5, The aforementioned controller, The system further includes an abnormality determination unit that determines whether the braking torque applied to the wheel by the braking device cannot be controlled. If it is determined that the braking torque applied to the wheel by the braking device cannot be controlled, the torsion determination unit will not perform a determination of the torsion of the drive shaft. A vehicle control device characterized by the following features.

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