JP2021024493A - Vehicular steering device - Google Patents

Abstract

To provide a vehicular steering device capable of enhancing rigidity of a steering mechanism and obtaining stable steering responsiveness.SOLUTION: A vehicular steering device comprises a drive device 70 for steering right and left steering wheels in response to steering of a handle. The drive device 70 includes: an actuator 71a for driving a left steering wheel; an actuator 71b for driving a right steering wheel; a knuckle arm 6a of the left steering wheel; a knuckle arm 6b of the right steering wheel; a coupling rod 76 for coupling between the right and left knuckle arms 6a, 6b; and a link mechanism containing joints 77 for connecting each of the parts. The actuator 71a for driving the left steering wheel and the actuator 71b for driving the right steering wheel respectively include motors 73a, 73b, and expansion mechanisms 74a, 74b. A difference between a motor torque Fa of the actuator 71a for driving the left steering wheel, and a motor torque Fb of the actuator 71b for driving the right steering wheel is a positive or negative value.SELECTED DRAWING: Figure 3A

Description

The present invention relates to a vehicle steering device.

As a steering device for a vehicle, a steering reaction force generator (FFA: Force Feedback Actuator, steering mechanism) in which the driver steers, and a tire steering device (RWA: Road Wheel Actuator, steering mechanism) for steering the vehicle. There is a steer-by-wire (SBW) type vehicle steering device that is mechanically separated from the steering wheel. Such an SBW type vehicle steering device has a configuration in which a steering mechanism and a steering mechanism are electrically connected via a control unit, and control between the steering mechanism and the steering mechanism is performed by an electric signal. is there.

For example, in Patent Document 1 below, in the SBW type vehicle steering device, steering actuators are provided on the left and right steering wheels, respectively, and each of them can be operated independently as a fail-safe mechanism. , A technique is disclosed in which a safe bar that mechanically connects the left and right tie rods is provided, and even if one steering actuator becomes inoperable, the steering can be steered by the other steering actuator that remains through the safe bar. ..

Japanese Patent No. 5493835

In a so-called rack and pinion type steering mechanism, tie rods are arranged between the rack and the knuckle arm, and each is connected by a ball joint. The ball joint is a region with low rigidity (low rigidity region) having a predetermined tolerance in design, and becomes a factor of wobbling and deterioration of steering response when the vehicle goes straight due to mechanical factors such as rattling. The SBW type vehicle steering device has more joints such as a safe bar, a tie rod, and a knuckle arm as in the above-mentioned conventional technique. Therefore, the low rigidity region including these joints may cause a decrease in steering response.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a steering device for a vehicle capable of increasing the rigidity of a steering mechanism and obtaining a stable steering response.

In order to achieve the above object, the vehicle steering device according to one aspect of the present invention includes a driving device that steers the left and right steering wheels in response to steering of the steering wheel, and a control unit that controls the driving device. The drive device is provided with a left steering wheel drive actuator whose one end is swingably supported by the chassis of the vehicle, and a mirror arrangement of the left steering wheel drive actuator and the vehicle in the straight-ahead direction. The right steering wheel drive actuator, one end of which is swingably supported by the chassis of the vehicle, and the left steering wheel knuckle arm to which the other end of the left steering wheel drive actuator is connected, the right steering wheel. A link mechanism including a knuckle arm of a right steering wheel to which the other end of a wheel driving actuator is connected, a connecting rod connecting between the left and right knuckle arms, and a joint connecting each part is provided. The left steering wheel drive actuator and the right steering wheel drive actuator each include a motor whose torque is controlled by the control unit and a telescopic mechanism that converts the rotational motion of the motor into a linear motion. The control unit controls so that the difference between the motor torque of the left steering wheel drive actuator and the motor torque of the right steering wheel drive actuator becomes a positive or negative value.

According to the above configuration, the rigidity of the steering mechanism can be increased. As a result, stable steering response can be obtained.

As a desirable embodiment of the vehicle steering device, the control unit has a preload that the difference between the motor torque of the left steering wheel driving actuator and the motor torque of the right steering wheel driving actuator gives to the link mechanism. It is preferable to control so as to be.

As a result, rattling or the like in the low-rigidity region of the link mechanism including each joint can be suppressed, and the rigidity of the steering mechanism can be increased.

As a desirable embodiment of the vehicle steering device, the control unit has a difference between the motor torque of the left steering wheel driving actuator and the motor torque of the right steering wheel driving actuator regardless of the steering angle of the steering wheel. Is preferably controlled so as to be constant.

This makes it possible to improve the controllability when traveling straight. In addition, since the rigidity of turning back and forth increases, stable steering response can be obtained.

As a desirable embodiment of the vehicle steering device, in the control unit, the magnitude of the motor torque acting in the feeding direction of the expansion / contraction mechanism of the left steering wheel drive actuator is determined by the expansion / contraction mechanism of the right steering wheel drive actuator. It is preferable to control the torque so that it is larger than the motor torque acting in the feeding direction.

As a desirable embodiment of the vehicle steering device, the control unit has a magnitude of motor torque acting in the extension direction of the expansion / contraction mechanism of the left steering wheel drive actuator and an extension mechanism of the right steering wheel drive actuator. It is preferable to control so that the motor torque acting in the direction has the same magnitude.

As a desirable embodiment of the vehicle steering device, in the control unit, the magnitude of the motor torque acting in the feeding direction of the expansion / contraction mechanism of the left steering wheel drive actuator is determined by the expansion / contraction mechanism of the right steering wheel drive actuator. It is preferable to control the torque so that it is smaller than the motor torque acting in the feeding direction.

As a result, the rigidity of the steering mechanism can be increased.

As a desirable embodiment of the vehicle steering device, in the control unit, the magnitude of the motor torque acting in the feeding direction of the expansion / contraction mechanism of the left steering wheel drive actuator is determined by the expansion / contraction mechanism of the right steering wheel drive actuator. It is preferable to control the torque so that it is smaller than the motor torque acting in the feeding direction.

As a desirable embodiment of the vehicle steering device, the control unit has a magnitude of motor torque acting in the feeding direction of the expansion / contraction mechanism of the left steering wheel driving actuator and the feeding of the expansion / contraction mechanism of the right steering wheel driving actuator. It is preferable to control so that the motor torque acting in the direction has the same magnitude.

As a desirable embodiment of the vehicle steering device, in the control unit, the magnitude of the motor torque acting in the feeding direction of the expansion / contraction mechanism of the left steering wheel drive actuator is determined by the expansion / contraction mechanism of the right steering wheel drive actuator. It is preferable to control the torque so that it is larger than the motor torque acting in the feeding direction.

As a result, the rigidity of the steering mechanism can be effectively increased.

According to the present invention, it is possible to provide a steering device for a vehicle capable of increasing the rigidity of the steering mechanism and obtaining a stable steering response.

FIG. 1 is a diagram showing an overall configuration of a steering device for a vehicle of a steer-by-wire type according to the first embodiment. FIG. 2 is a schematic diagram showing the hardware configuration of the control unit that controls the SBW system. FIG. 3A is a diagram showing an operation example of the drive device according to the first embodiment. FIG. 3B is a second diagram showing an operation example of the drive device according to the first embodiment. FIG. 3C is a third diagram showing an operation example of the drive device according to the first embodiment. FIG. 4 is a diagram showing the relationship between the motor torque Fa of the drive actuator on the left side of the drive device according to the first embodiment and the motor torque Fb of the drive actuator on the right side. FIG. 5A is a diagram showing an operation example of the drive device according to the second embodiment. FIG. 5B is a second diagram showing an operation example of the drive device according to the second embodiment. FIG. 5C is a third diagram showing an operation example of the drive device according to the second embodiment. FIG. 6 is a diagram showing the relationship between the motor torque Fa of the drive actuator on the left side of the drive device according to the second embodiment and the motor torque Fb of the drive actuator on the right side. FIG. 7 is a diagram showing an example of a schematic cross-sectional structure of the expansion / contraction mechanism of the drive actuator.

Hereinafter, embodiments for carrying out the invention (hereinafter referred to as embodiments) will be described in detail with reference to the drawings. The present invention is not limited to the following embodiments. In addition, the components in the following embodiments include those that can be easily assumed by those skilled in the art, those that are substantially the same, that is, those in a so-called equal range. Further, the components disclosed in the following embodiments can be appropriately combined.

(Embodiment 1)
FIG. 1 is a diagram showing an overall configuration of a steering device for a vehicle of a steer-by-wire type according to the first embodiment. In the steer-by-wire (SBW: Steer By Wire) type vehicle steering device (hereinafter, also referred to as “SBW system”) shown in FIG. 1, the steering mechanism including the steering wheel 1 and the like is operated by an electric signal. It is a system that transmits to the steering mechanism consisting of 8R and the like. As shown in FIG. 1, the SBW system includes a reaction force device 60 and a drive device 70, and a control unit (ECU) 50 as a control unit controls both devices.

The reaction force device 60 includes a torque sensor 10 that detects the steering torque Ts of the handle 1, a steering angle sensor 14 that detects the steering angle θh, a reduction mechanism 3, an angle sensor 74, a reaction force motor 61, and the like. Each of these components is provided on the column shaft 2 of the handle 1.

The reaction force device 60 detects the steering angle θh by the steering angle sensor 14, and at the same time, transmits the motion state of the vehicle transmitted from the steering wheels 8L and 8R to the driver as a reaction force torque. The reaction force torque is generated by the reaction force motor 61. The torque sensor 10 detects the steering torque Ts. Further, the angle sensor 74 detects the motor angle θm of the reaction force motor 61. In the steer-by-wire type vehicle steering device according to the present embodiment, the steering angle sensor 14 may be provided, and the angle sensor 74 may not be required.

The drive device 70 includes drive actuators 71a and 71b, motor control units 72a and 72b, and the like. The driving force generated by the driving actuator 71a is connected to the steering wheels 8L and 8R via the knuckle arms 6a and 6b and further via the hub units 7a and 7b.

The drive actuators 71a and 71b are provided corresponding to the steering wheels 8L and 8R, respectively. The drive actuators 71a and 71b include motors 73a and 73b, expansion / contraction mechanisms 74a and 74b, angle sensors 75a and 75b, respectively.

The expansion / contraction mechanism 74a, 74b includes housings 742a, 742b that slidably support the rods 741a, 741b and the rods 741a, 741b. One end of the drive actuators 71a and 71b is swingably supported by mounting portions 743a and 743b provided on the housings 742a and 742b with respect to a chassis (not shown) of the vehicle. At the other end of the drive actuators 71a and 71b, the rods 741a and 741b and the knuckle arms 6a and 6b are connected via a joint 77. The joint 77 is, for example, a ball joint, but is not limited to the ball joint, and may be, for example, a pillow ball or an elastic bush.

The drive device 70 includes a connecting rod 76 that connects the left and right knuckle arms 6a and the knuckle arms 6b. The knuckle arm 6a and the connecting rod 76 are connected via a joint 77. The knuckle arm 6b and the connecting rod 76 are connected via a joint 77.

In the present embodiment, the left and right knuckle arms 6a and 6b, the connecting rod 76, and the joint 77 connecting each part constitute a link mechanism. Each joint 77 has a tolerance for movably connecting a plurality of members. That is, the link mechanism has a low-rigidity region that becomes a mechanical factor such as rattling due to the tolerance of each joint 77 or the like.

In the above-described configuration, the drive device 70 drives the motors 73a and 73b, and the rotational motion of the motors 73a and 73b is converted into a linear motion by the expansion and contraction mechanisms 74a and 74b. The driving force converted into linear motion is applied to the knuckle arms 6a and 6b via the joint 77. Then, the steering wheels 8L and 8R are steered by the knuckle arms 6a and 6b rotating around the pivot 78 by the driving force applied from the motors 73a and 73b via the telescopic mechanisms 74a and 74b.

Angle sensors 75a and 75b are arranged on the drive actuators 71a and 71b to detect the steering angles θt of the steering wheels 8L and 8R. In order to coordinately control the reaction force device 60 and the drive device 70, the ECU 50 adds information such as steering angle θh and steering angle θt output from both devices, and based on vehicle speed Vs from the vehicle speed sensor 12 and the like. The voltage control command values Vref1 for driving and controlling the reaction force motor 61 and the voltage control command values Vref2a and Vref2b for driving and controlling the motors 73a and 73b of the driving actuators 71a and 71b are generated. The motors 73a and 73b are torque-controlled by the voltage control command values Vref2a and Vref2b. Note that FIG. 1 shows an example in which angle sensors 75a and 75b are provided to detect the angles of the motors 73a and 73b and detect the steering angles θt of the steering wheels 8L and 8R, but the present invention is not limited to this. As long as the positions of the telescopic mechanisms 74a and 74b can be detected, the angle sensors 75a and 75b may be replaced with other position detecting means.

Electric power is supplied to the control unit (ECU) 50 from the battery 13, and an ignition key signal is input via the ignition key 11. The control unit 50 calculates the current command value based on the steering torque Ts detected by the torque sensor 10 and the vehicle speed Vs detected by the vehicle speed sensor 12, and the reaction force motor 61 and the drive actuators 71a and 71b. The current supplied to the motors 73a and 73b is controlled.

An in-vehicle network such as a CAN (Controller Area Network) 40 that exchanges various vehicle information is connected to the control unit 50. Further, a non-CAN 41 that transmits / receives communications other than the CAN 40, analog / digital signals, radio waves, and the like can also be connected to the control unit 50.

The control unit 50 is mainly composed of a CPU (including an MCU, an MPU, etc.). FIG. 2 is a schematic diagram showing the hardware configuration of the control unit that controls the SBW system.

The control computer 1100 constituting the control unit 50 includes a CPU (Central Processing Unit) 1001, a ROM (Read Only Memory) 1002, a RAM (Random Access Memory) 1003, an EEPROM (Electrically Erasable Programmable ROM) 1004, and an interface (I / F). ) 1005, A / D (Analog / Digital) converter 1006, PWM (Pulse Width Modulation) controller 1007, etc., which are connected to the bus.

The CPU 1001 is a processing device that controls the SBW system by executing a computer program for controlling the SBW system (hereinafter referred to as a control program).

The ROM 1002 stores a control program for controlling the SBW system. Further, the RAM 1003 is used as a work memory for operating the control program. The EEPROM 1004 stores control data and the like input and output by the control program. The control data is used on the control computer program expanded in the RAM 1003 after the power is turned on to the control unit 50, and is overwritten on the EEPROM 1004 at a predetermined timing.

The ROM 1002, RAM 1003, EEPROM 1004, and the like are storage devices for storing information, and are storage devices (primary storage devices) that can be directly accessed by the CPU 1001.

The A / D converter 1006 inputs signals such as steering torque Ts and steering angle θh and converts them into digital signals.

Interface 1005 is connected to CAN 40. The interface 1005 is for receiving a vehicle speed V signal (vehicle speed pulse) from the vehicle speed sensor 12.

The PWM controller 1007 outputs PWM control signals for each phase of UVW based on the current command values for the reaction force motor 61 and the motors 73a and 73b.

The control operation of the drive device 70 in the configuration of the first embodiment described above will be described with reference to FIGS. 3A, 3B, 3C, and 4.

FIG. 3A is a diagram showing an operation example of the drive device according to the first embodiment. FIG. 3B is a second diagram showing an operation example of the drive device according to the first embodiment. FIG. 3C is a third diagram showing an operation example of the drive device according to the first embodiment. FIG. 3A shows a state diagram when steering to the right, FIG. 3B shows a state diagram when the steering angle θh is “0”, and FIG. 3C shows a state diagram when steering to the left. Shown. In FIGS. 3A, 3B, and 3C, the motor torque of the drive actuator 71a on the left side is Fa, and the motor torque of the drive actuator 71b on the right side is Fb.

FIG. 4 is a diagram showing the relationship between the motor torque Fa of the drive actuator on the left side of the drive device according to the first embodiment and the motor torque Fb of the drive actuator on the right side. In FIG. 4, the horizontal axis is the steering angle θh, and the vertical axis is the torque F. In the example shown in FIG. 4, the direction in which the drive actuators 71a and 71b extend the rods 741a and 741b from the housings 742a and 742b is the + (plus) direction of the torque F. Further, in the example shown in FIG. 4, the right turning direction is the + (plus) direction of the steering angle θh.

In the link mechanism including the knuckle arms 6a and 6b, the connecting rod 76, and each joint 77, the torque difference f between the motor torque Fa of the drive actuator 71a on the left side and the motor torque Fb of the drive actuator 71b on the right side is used as a preload. Be urged. This torque difference f is represented by the following equation (1).

f = Fa-Fb ... (1)

When the motor torque Fa of the left drive actuator 71a and the motor torque Fb of the right drive actuator 71b are equal, in other words, for example, the driving force generated in the direction in which the left drive actuator 71a feeds out the rod 741a. If the driving actuator 71b on the right side has the same driving force generated in the direction in which the rod 741b is fed, the knuckle arms 6a and 6b, the connecting rod 76, and each joint 77 are included as derived from the above equation (1). The torque difference f applied to each part of the link mechanism is approximately 0. In this case, mechanical factors such as rattling in the low-rigidity region of the link mechanism cause wobbling of the vehicle and deterioration of steering response.

In the present embodiment, as shown in FIG. 4, the motor torque Fa in the + (plus) direction of the drive actuator 71a on the left side and the motor torque Fb (−Fb) in the − (minus) direction of the drive actuator 71b on the right side. Is different from.

Specifically, when the steering angle θh is in the “+ (plus)” region, that is, when the vehicle is steered to the right, as shown in FIG. 3A, the motor acts in the direction of feeding out the rod 741a of the drive actuator 71a on the left side. The magnitude of the torque Fa is made larger than the motor torque Fb acting in the feeding direction of the rod 741b of the drive actuator 71b on the right side.

Further, when the steering angle θh is “0”, that is, when traveling straight, as shown in FIG. 3B, the magnitude of the motor torque Fa acting in the feeding direction of the rod 741a of the drive actuator 71a on the left side and the drive actuator 71b on the right side. The magnitude of the motor torque Fb acting in the feeding direction of the rod 741b is the same in the opposite directions.

Further, when the steering angle θh is in the “− (minus)” region, that is, when the vehicle is steered to the left, as shown in FIG. 3C, the motor torque Fa acting in the feeding direction of the rod 741a of the drive actuator 71a on the left side. The size is smaller than the motor torque Fb acting in the feeding direction of the rod 741b of the drive actuator 71b on the right side.

Therefore, the torque difference f represented by the above equation (1) is urged as a preload to each part of the link mechanism including the knuckle arms 6a and 6b, the connecting rod 76, and each joint 77. As a result, rattling or the like in the low rigidity region of the link mechanism including each joint 77 can be suppressed, and the rigidity of the steering mechanism can be increased.

Further, in the present embodiment, as shown in FIG. 4, the torque difference f between the motor torque Fa of the left drive actuator 71a and the motor torque Fb of the right drive actuator 71b is constant regardless of the steering angle. To control. As a result, stable steering response can be obtained.

Increasing the rigidity of the steering mechanism means, for example, increasing the rigidity of the so-called on-center near the center of the steering wheel when the vehicle is running. That is, since the drive actuators 71a and 71b have high rigidity at the start of movement, the controllability can be improved, and the controllability when traveling straight, for example, the lane keep assist function can be improved.

Further, increasing the rigidity of the steering mechanism means that when the steering wheel is turned to a certain steering angle while maintaining a constant preload, the rigidity of turning up and back is increased in the vicinity of the steering angle. That is, for example, controllability such as an auto parking (automatic parking) function is improved.

(Embodiment 2)
FIG. 5A is a diagram showing an operation example of the drive device according to the second embodiment. FIG. 5B is a second diagram showing an operation example of the drive device according to the second embodiment. FIG. 5C is a third diagram showing an operation example of the drive device according to the second embodiment. FIG. 5A shows a state diagram when steering to the right, FIG. 5B shows a state diagram when the steering angle θh is “0”, and FIG. 5C shows a state diagram when steering to the left. Shown.

FIG. 6 is a diagram showing the relationship between the motor torque Fa of the drive actuator on the left side of the drive device according to the second embodiment and the motor torque Fb of the drive actuator on the right side.

In the second embodiment, when the steering angle θh is in the “+ (plus)” region, that is, when the motor is steered to the right, the motor acts in the feeding direction of the rod 741a of the drive actuator 71a on the left side, as shown in FIG. 5A. The magnitude of the torque Fa is made smaller than the motor torque Fb acting in the feeding direction of the rod 741b of the drive actuator 71b on the right side.

Further, when the steering angle θh is “0”, that is, when traveling straight, as shown in FIG. 5B, the magnitude of the motor torque Fa acting in the feeding direction of the rod 741a of the drive actuator 71a on the left side and the drive actuator 71b on the right side. The magnitude of the motor torque Fb acting in the feeding direction of the rod 741b is the same in the opposite directions.

Further, when the steering angle θh is in the “− (minus)” region, that is, when the vehicle is steered to the left, the motor torque Fa acting in the feed-in direction of the rod 741a of the drive actuator 71a on the left side, as shown in FIG. 5C. The size is made larger than the motor torque Fb acting in the feeding direction of the rod 741b of the drive actuator 71b on the right side.

Also in the second embodiment, similarly to the first embodiment, the torque difference f shown in the above formula (1) is attached as a preload to each part of the link mechanism including the knuckle arms 6a and 6b, the connecting rod 76, and each joint 77. Be forced. As a result, rattling or the like in the low rigidity region of the link mechanism including each joint 77 can be suppressed, and the rigidity of the steering mechanism can be increased.

Further, as shown in FIG. 6, the torque difference f between the motor torque Fa of the left drive actuator 71a and the motor torque Fb of the right drive actuator 71b is controlled to be constant regardless of the steering angle. As a result, stable steering response can be obtained.

In the first embodiment described above, the torque difference f between the motor torque Fa of the drive actuator 71a on the left side and the motor torque Fb of the drive actuator 71b on the right side is a positive preload for the link mechanism including each joint 77. On the other hand (see FIG. 4 and equation (1)), in the present embodiment, the torque difference f between the motor torque Fa of the drive actuator 71a on the left side and the motor torque Fb of the drive actuator 71b on the right side is the joint 77. Negative preload is applied to the link mechanism including (see FIG. 6 and equation (1)).

When a positive preload is applied to the link mechanism including each joint 77, a so-called buckling phenomenon is caused due to misalignment of each part constituting the link mechanism, and elastic deflection in the bending direction is generated. there is a possibility. In the present embodiment, a negative preload is urged to the link mechanism including each joint 77, and a pulling force acts on each part of the link mechanism, so that the rigidity of the link mechanism is effectively increased. be able to.

Further, in the first embodiment described above, the expansion / contraction mechanisms 74a and 74b of the drive actuators 71a and 71b are also urged with a positive preload. FIG. 7 is a diagram showing an example of a schematic cross-sectional structure of the expansion / contraction mechanism of the drive actuator.

The telescopic mechanisms 74a and 74b are slidably supported by the rods 741a and 741b with respect to the housings 742a and 742b via the ball screw mechanisms 744a and 744b. When a preload in the A, A'direction is urged between the rods 741a, 741b and the housings 742a, 742b, a force in the rotational direction around the swing axis X of the mounting portions 743a, 743b is generated. As a result, a radial load is applied to the ball screw mechanisms 744a and 744b, and the load increases.

On the other hand, in the present embodiment, the preload in the B and B'directions is urged between the rods 741a and 741b and the housings 742a and 742b. As a result, a pulling force acts between the rods 741a and 741b and the housings 742a and 742b, so that the preload in the B and B'directions is an axial load connecting the connection point with the link mechanism and the connection point with the chassis. It becomes. As a result, the load applied to the ball screw mechanisms 744a and 744b in the radial direction is suppressed, and the preload generated between the rods 741a and 741b and the housings 742a and 742b can be efficiently utilized. Therefore, the entire steering mechanism including the drive actuators 71a and 71b can be made highly rigid.

In the above-described embodiment, the mode in which both the drive actuators 71a and 71b are operated has been described, but the configuration is provided with a connecting rod 76 for connecting the left and right knuckle arms 6a and the knuckle arms 6b. Therefore, for example, even if one of the drive actuators 71a and 71b becomes inoperable, the remaining one can steer.

Further, the figures used above are conceptual diagrams for qualitatively explaining the present disclosure, and are not limited thereto. Further, the above-described embodiment is an example of a preferred embodiment of the present disclosure, but the present invention is not limited to this, and various modifications can be made without departing from the gist of the present disclosure.

1 Handle 2 Column shaft 3 Deceleration mechanism 6a, 6b Knuckle arm 7a, 7b Hub unit 8L, 8R Steering wheel 10 Torque sensor 11 Ignition key 12 Vehicle speed sensor 13 Battery 14 Steering angle sensor 50 Control unit (ECU)
60 Reaction force device 61 Reaction force motor 70 Drive device 71a, 71b Drive actuator 72a, 72b Motor control unit 73a, 73b Motor 74a, 74b Telescopic mechanism 75a, 75b Angle sensor 76 Connecting rod 77 Joint 78 Pivot 741a, 741b Rod 742a , 742b Housing 743a, 743b Mounting part 1001 CPU
1005 Interface 1006 A / D Converter 1007 PWM Controller 1100 Control Computer (MCU)

Claims (9)

A drive device that steers the left and right steering wheels according to the steering of the steering wheel,
A control unit that controls the drive device and
With
The drive device
An actuator for driving left steering wheels, one end of which is swingably supported by the chassis of the vehicle,
The left steering wheel drive actuator, the right steering wheel drive actuator which is mirror-arranged in the straight direction of the vehicle and one end of which is swingably supported by the chassis of the vehicle,
The knuckle arm of the left steering wheel to which the other end of the left steering wheel driving actuator is connected, the knuckle arm of the right steering wheel to which the other end of the right steering wheel driving actuator is connected, and the left and right knuckles. A link mechanism including a connecting rod for connecting the arms and a joint for connecting each part,
With
The left steering wheel driving actuator and the right steering wheel driving actuator each include a motor whose torque is controlled by the control unit and a telescopic mechanism that converts the rotational motion of the motor into a linear motion.
The control unit
The difference between the motor torque of the left steering wheel driving actuator and the motor torque of the right steering wheel driving actuator is controlled to be a positive or negative value.
Steering device for vehicles. The control unit
The difference between the motor torque of the left steering wheel driving actuator and the motor torque of the right steering wheel driving actuator is controlled to be a preload applied to the link mechanism.
The vehicle steering device according to claim 1. The control unit
It is controlled so that the difference between the motor torque of the left steering wheel driving actuator and the motor torque of the right steering wheel driving actuator is constant regardless of the steering angle of the steering wheel.
The vehicle steering device according to claim 2. The control unit
The magnitude of the motor torque acting in the extension direction of the expansion / contraction mechanism of the left steering wheel drive actuator is controlled to be larger than the motor torque acting in the extension direction of the expansion / contraction mechanism of the right steering wheel drive actuator.
The vehicle steering device according to claim 2 or 3. The control unit
The magnitude of the motor torque acting in the extension direction of the expansion / contraction mechanism of the left steering wheel drive actuator is controlled to be the same as the magnitude of the motor torque acting in the extension direction of the expansion / contraction mechanism of the right steering wheel drive actuator. ,
The vehicle steering device according to any one of claims 2 to 4. The control unit
The magnitude of the motor torque acting in the extension direction of the expansion / contraction mechanism of the left steering wheel drive actuator is controlled to be smaller than the motor torque acting in the extension direction of the expansion / contraction mechanism of the right steering wheel drive actuator.
The vehicle steering device according to any one of claims 2 to 5. The control unit
The magnitude of the motor torque acting in the extension direction of the expansion / contraction mechanism of the left steering wheel drive actuator is controlled to be smaller than the motor torque acting in the extension direction of the expansion / contraction mechanism of the right steering wheel drive actuator.
The vehicle steering device according to claim 2 or 3. The control unit
Control so that the magnitude of the motor torque acting in the carry-in direction of the expansion / contraction mechanism of the left steering wheel drive actuator and the motor torque acting in the carry-in direction of the expansion / contraction mechanism of the right steering wheel drive actuator are the same magnitude. ,
The vehicle steering device according to any one of claims 2 to 4. The control unit
The magnitude of the motor torque acting in the extension direction of the expansion / contraction mechanism of the left steering wheel drive actuator is controlled to be larger than the motor torque acting in the extension direction of the expansion / contraction mechanism of the right steering wheel drive actuator.
The vehicle steering device according to any one of claims 2 to 5.

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