JPH04135974A - Steering device for vehicle - Google Patents

Abstract

PURPOSE:To enhance operation feeling as well as to prevent a steering wheel from being uselessly operated by imparting rotating resistance to a first shaft to which the steering wheel is connected through a rotation restraining means. CONSTITUTION:A steering device 1 permits respective cylinders 7a and 7b to be supplied with/emptied of working oil with a hydraulic control valve 12 switched over, so that a steering rod 5 is thereby disposed in the transverse direction while a right and a left front wheel 4 are steered. A steering shaft 12 is divided into a first shaft 10a onto the upper section of which a handle 8 is mounted, and a second shaft 10b connected to a steering rod 5 side via a rack and pinion 9, wherein both of the sections are mutually connected via a blind sector joint 13, the first shaft 10a and the second shaft 10b are provided with a first and a second steering sensor 14 and 15 respectively, which detect each rotating angle of the shafts, and an electromagnetic brake 19 which acts as a rotation restraining means imparting rotating resistance, is disposed at the first shaft 10a.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a steering device for a vehicle, particularly a vehicle that converts rotational displacement of a steering wheel into displacement in the vehicle width direction via a gear mechanism to steer front wheels. The present invention relates to a steering device.

(Prior Art) In recent years, a steering wheel and a driving means for steering the front wheels are provided separately, and when the steering wheel is operated, the left and right front wheels are automatically turned by the driving means according to the steering angle of the wheel. A steering device that steers the vehicle is known.

For example, according to Japanese Unexamined Patent Publication No. 1663/1983, a steering wheel, a hydraulic actuator provided independently from the steering wheel for steering front wheels,
a controller that controls the operation of the hydraulic actuator based on a signal from a steering angle sensor that detects a steering angle of the steering wheel, and when the steering wheel is operated, a target steering angle corresponding to the steering angle of the wheel is set. The hydraulic actuator is controlled to automatically steer the left and right front wheels.

On the other hand, the steering shaft is divided into a first shaft connected to the front wheel side via a gear mechanism and a second shaft connected to the steering wheel.
, by connecting the second shaft with an insensitive joint that allows relative rotation between the two shafts, the second shaft is provided independently of the steering wheel according to the steering angle of the steering wheel within the allowable relative rotation range of both shafts. The left and right front wheels are automatically steered by the drive means, and
A steering device has been developed in which the relative rotation between a first shaft and a second shaft is restricted as necessary so that both shafts can be rotated integrally by manual operation.

(Problem to be solved by the invention) By the way, as mentioned above, the steering shaft is the first
When the steering wheel is divided into a second shaft and both shafts are relatively rotatable, the rotational resistance between the two shafts is low, so that when operating the steering wheel connected to the second shaft, The steering wheel has an extremely poor operational feel, giving the driver a sense of unease, and the steering wheel is too light, leading to careless operation of the steering wheel, which can cause the front wheels to automatically roll by the drive means against the driver's will. There was a risk that the behavior of the vehicle would become unstable due to the steering.

Therefore, in the present invention, the steering shaft between the steering wheel and the gear mechanism is divided into a first shaft on the steering wheel side and a second shaft on the gear mechanism side, and these first and second shafts are relative to each other. A steering system for a vehicle configured to be rotatably connected to each other and to automatically steer left and right front wheels by a drive means in response to operation of the steering wheel within a relative rotatable range of the steering wheel. The object of the present invention is to improve the operational feeling of the wheel by providing a necessary rotational resistance, and to improve the running stability of the vehicle by preventing as much as possible unnecessary operation of the steering wheel.

(Means for Solving the Problems) In order to solve the above problems, the present invention is characterized by the following configuration.

First, the invention according to the first claim of the present application (hereinafter referred to as the first invention) is a steering device for a vehicle that converts rotational displacement of a steering wheel into displacement in the vehicle width direction via a gear mechanism to steer the front wheels. In this method, the steering shaft between the steering wheel and the gear mechanism is divided into a first shaft on the steering wheel side and a second shaft on the gear mechanism side, and these first and second shafts are connected to both shafts. a first steering angle sensor that detects a rotation angle of the first shaft; a second steering angle sensor that detects a rotation angle of the second shaft; an actuator for steering;
control means for controlling the operation of the actuator within an allowable range of relative rotation of the first and second shafts according to the driving state based on signals from the first and second steering angle sensors; The present invention is characterized in that a rotation regulating means for applying rotational resistance to one shaft is provided.

Further, the invention according to the second claim of the present application (hereinafter referred to as the second invention) is a steering device having the same configuration as the first invention, in which the rotation regulating means for applying rotational resistance to the first shaft is replaced by an electromagnetic brake. It is characterized by being constructed by

Furthermore, the invention according to the third claim of the present application (hereinafter referred to as the third invention), like the second invention, comprises the rotation regulating means by an electromagnetic brake, and in addition, the operation of the electromagnetic brake is controlled. The present invention is characterized in that a rotation control means for controlling the rotation according to at least the vehicle speed is provided.

Furthermore, the invention according to the fourth claim of the present application (hereinafter referred to as the fourth invention) is a vehicle steering system configured similarly to the first to third inventions, in which rotational resistance is applied to the first shaft. The rotation regulating means is connected to the first shaft and the second shaft.
It is characterized by being constructed by an elastic body and a torsion bar provided between the shaft and the shaft.

(Function) According to the first to fourth inventions, in any of the first to fourth inventions,
The shaft and the second shaft are connected to be relatively rotatable by an insensitive joint, and within this relative rotation tolerance range, when the steering wheel is operated by the driver, the first shaft to which the steering wheel is connected Based on the signal from the first steering angle sensor that detects the steering angle of the shaft, the control means controls the operation of the actuator that steers the front wheels according to the driving condition. It will be steered accordingly.

According to the first invention, rotational resistance is applied to the first shaft to which the steering wheel is connected by the rotation regulating means, whereby the first shaft and the second shaft are in a state where they can rotate relative to each other. Even if the steering wheel is too light, the necessary rotational resistance is applied to the steering wheel connected to the first shaft, which improves the operational feeling of the steering wheel and eliminates unnecessary rotational resistance caused by the steering wheel being too light. Operation is reliably prevented and the running stability of the vehicle is improved.

Further, according to the second invention, since the rotation regulating means for applying rotational resistance to the first shaft to which the steering wheel is connected is constituted by an electromagnetic brake, the amount of electricity applied to the electromagnetic brake can be controlled to brake the first shaft. By adjusting the force, it is possible to vary the rotational resistance that acts on the steering wheel connected to the first shaft. This allows, for example, to vary the rotational resistance that acts on the steering wheel appropriately depending on the driving condition of the vehicle. Can be adjusted.

Furthermore, according to the third aspect of the invention, since the rotation control means is provided for controlling the operation of the electromagnetic brake as the rotation regulating means in accordance with at least the vehicle speed, for example, the braking force of the electromagnetic brake can be adjusted in response to an increase in the vehicle speed. By increasing this, it becomes possible to gradually increase the rotational resistance acting on the steering wheel when transitioning from low-speed driving to high-speed driving, which further improves straight-line stability, especially when driving at high speeds.

Furthermore, according to the fourth invention, since the rotation regulating means is constituted by the torsion bar and the elastic body provided between the first shaft and the second shaft, deviation in the rotational direction between the two shafts is prevented. is small, the frictional resistance of the elastic body acts as rotational resistance between the two shafts, and the first
If the deviation between the shaft and the second shaft increases,
The spring force (torsional resistance) of the torsion bar acts as a rotational resistance between the two shafts, making it possible to apply the required rotational resistance between the two shafts with a relatively simple configuration.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is an overall system diagram of a vehicle steering system, and the steering system 1 consists of a steering rod to which left and right front wheels 4, 4 are connected via tie rods 2.2 and knuckle arms 3, 3 at both ends. 5, a hydraulic cylinder 7 as an actuator for steering the front wheels 4.4, each of which has left and right cylinder chambers 7a, 7b formed by a piston 6 integrally formed with the steering rod 5, and rotation of a handle 8. A steering shaft 10 that transmits displacement to the steering rod 5 via a rack and pinion machine ellipse 9, and hydraulic control for supplying and discharging hydraulic oil from an oil pump 11 to the left and right cylinder chambers 7a and 7b of the hydraulic cylinder 7. By switching the hydraulic control valve 12, hydraulic oil is supplied to and discharged from each of the cylinder chambers 7a and 7b, thereby displacing the steering rod 5 in the vehicle width direction and steering the left and right front wheels. It is designed to steer 4°4.

On the other hand, the steering shaft 10 is exposed to the first shaft 10a to which the handle 8 is attached to the upper end, and the first shaft 10b connected to the steering rod 5 side via the rack and pinion 9. The first of these. The second shafts 10a and 10b are connected via an insensitive joint 13 that allows relative rotation between the two, and
The first shaft 10a detects the respective rotation angles of the first shaft 10a and the second shaft 10b. Second steering angle sensor 14.15
is provided. Furthermore, the first. A hydraulic cylinder 16 is provided as an actuator for variably adjusting the allowable relative rotation range of the second shafts 10a, 10b, and this hydraulic cylinder 16
A hydraulic control valve 18 is provided between the hydraulic cylinder 16 and the oil pump 17, and by switching the hydraulic control valve 18, hydraulic oil is supplied to and discharged from the hydraulic cylinder 16. Further, an electromagnetic brake 1 is provided as a rotation regulating means for imparting rotational resistance to the first shaft 10a.
9 are arranged.

A control unit 20 for controlling the operation of the steering device 1 is provided, and this control unit 20 includes the first. A signal from the second steering angle sensor 14.15, a signal from the vehicle speed sensor 21 that detects the vehicle speed,
Brake switch 2 that detects the brake pedal depression state
2 and the yaw rate sensor 23 that acts on the vehicle body.
, a signal from the G sensor 24 that detects the lateral G acting on the vehicle body, and a signal from the wiper switch 25 that detects the operating state of the wiper, and based on these input signals, The control unit 2
From 0, control signals are outputted to the hydraulic control valves 12, 18 and the electromagnetic brake 19 to control their operations. As a result, the above first,
When the second shafts 10a and 10b are relatively rotatable, by operating the handle 8 connected to the first shaft 10a, the front wheels 4.
The steering amount of No. 4 is automatically controlled to be a predetermined amount corresponding to the steering angle of the steering wheel.

Here, the configuration of the insensitive joint 13 and the electromagnetic brake 19 will be explained in more detail based on FIG. 2.3.
The insensitive joint 13 includes a cylindrical member 26 that is integrally formed at the upper end of the second shaft 10b and has a tapered hole 26a that expands in the axial direction, and a cylindrical member 26 that is formed on the outer periphery of the lower end of the first shaft Oa. It has two sleeves to which a pin member 28 is fixed, which is fitted onto the spline 27 and passes through the tapered hole 26a, and a coil spring 30 which biases the sleeve 29 in a predetermined direction. Hydraulic cylinder 16 that slides sleeve 29 in the axial direction
A piston rod 1.6a is connected to the piston rod 1.6a.

Therefore, as shown in FIG. 2, when the bottle member 28 is in contact with the end of the tapered hole 26a, the relative rotation between the first and second shafts 10a, 10b is restricted, and the - - When the sleeve 29 physically rotates and, for example, hydraulic oil is supplied to the hydraulic cylinder 16 via the hydraulic control valve 18, the sleeve 29 moves against the coil spring 30, and accordingly, the bottle As the member 28 moves, the bottle member 28 becomes in a state where it can freely rotate within the opening range of the tapered hole 26a, thereby allowing relative rotation of the first and second shafts 10a and 10b. It looks like this.

A stroke sensor 31 is disposed between the sleeve 29 and the hydraulic cylinder 16, and the sensor 31 detects the movement amount 1 of the bottle member 28 based on the movement amount of the sleeve 29. 1. The permissible range of relative rotation between the second shaft is detected.

The above-mentioned TA brake 19 consists of a fixed side member 19b which is fixedly attached to a vehicle body side member 32 that rotatably supports the first shaft 10a, and has an electromagnet 9a installed therein, and a fixed side member 19b which is fixedly attached to the first shaft 10a side. The movable side member 19c is provided and rotates integrally with the first shaft 10a,
By energizing the electromagnet 19a installed in the fixed side member 19b, a brake rake force is generated between the electromagnet 19a and the movable side member 19c, and rotational resistance is applied to the first shaft 10a to which the handle 8 is connected. It has become.

Next, the front wheel steering control operation by the control unit 20 will be explained based on the flowchart shown in FIG. The steering wheel steering angle θh1 is input, and in step S2, the left and right front wheels 4, 4 are actually adjusted according to the steering wheel steering angle θh1.
Based on the difference between the target steering angle θh2 and the target steering angle θh2, it is determined whether or not it is the correction control timing. and,
When there is a difference between the above-mentioned steering wheel steering angle θhl and target steering angle θh2 and it is determined that it is correction control timing, the hydraulic cylinder 7 is driven in step S3, and the front wheel 4.
steer the vehicle in a predetermined direction. Next, in step S4, the value obtained by adding the correction amount by the hydraulic cylinder 7 to the steering wheel steering angle θh1 is determined to be 1. It is determined whether the target steering angle θh2 has been reached, and if YES, the operation of the hydraulic cylinder 7 is stopped in step S. When the determination is No, the hydraulic cylinder 7 is continuously driven, step S6 is executed, and it is determined whether the correction operation of the front wheels 4.4 by the hydraulic cylinder 7 has timed out. In the case of time-up, this control operation is immediately stopped in step S7, and if not, in step S8, the difference between the steering wheel steering angle θh1 and the target steering angle θh2 and the first
, relative rotation tolerance limit θ between the second shafts 10a and 10b
When compared with hO, if the difference between the steering wheel steering angle θh1 and the target steering angle θh2 exceeds the relative rotation permissible limit θh, step S7 is executed to stop the control operation, and the steering wheel steering angle θh□ If the difference between the target steering angle θh2 and the target steering angle θh2 is within the relative rotation tolerance range eho, correction control by the hydraulic cylinder 7 is subsequently performed.

Next, based on FIGS. 5 to 12, the control operation for determining the target steering angle θh2 corresponding to the steering wheel steering angle θh1 according to the driving state by the control unit 20 will be explained. As shown in FIG. unit 2
0 is the displacement acceleration θh1 of the steering wheel 8 obtained based on the signal from the first steering angle sensor 14 in step S10'.
Then, in step S11', it is determined whether the brake is depressed based on a signal from the brake switch 22. If the brake is depressed, in step S12', from the map showing the relationship between the steering speed and the corresponding correction amount A shown in FIG.
A correction amount AI corresponding to the steering speed when the brake is depressed is calculated, and in step 813', the target steering angle θh2 is set to the value obtained by adding the correction amount AI to the target steering angle θh2 in normal conditions. Further, when it is determined in step S11' that the brake is not depressed, in step S14', a correction amount A2 corresponding to the steering speed when the brake is not depressed is calculated from the map shown in FIG. In step S1,', the target steering angle θh2 is set to the value obtained by adding the correction amount A2 to the target steering angle θh2 in normal conditions. In this way, the target θh2 is set in correspondence with the steering angular speed and the brake depression state, so that when the steering speed is high and the brake is depressed, and prompt correction is required, the target steering angle By setting θh2 large, correction control can be performed quickly.

Further, FIG. 7 shows a control operation for setting the target steering angle θh2 according to the yaw rate acting on the vehicle body, and the control unit 20 in step 320'
When it is determined as YES, that is, the handle 8
When it is determined that the vehicle is hardly being steered, the yaw rate acting on the vehicle body is calculated in step 821' based on the signal from the yaw rate sensor 23, and then, in step 82', the yaw rate shown in FIG. 8 and the corresponding correction are calculated. A correction amount B corresponding to the yaw rate calculated in step 821' is calculated from a map showing the relationship with the amount B. Then, the target steering angle θh2 is set to a value obtained by subtracting the correction amount B from the target steering angle θh2 in normal times. In this way, when the yaw rate is acting, the target steering angle θh2 is adjusted so as to cancel out the influence of the yaw rate.
will be set.

Furthermore, Fig. 9 shows that the target steering angle θ is adjusted according to the lateral G acting on the vehicle body.
The control operation for setting h2 is shown. First, in step 33G', the lateral G acting on the vehicle body is inputted by the signal from the G sensor 24, and in step S31', the 10th
Calculate the correction amount C from the map showing the relationship between the horizontal G in the figure and the corresponding correction amount C. Next, step 832'
In this step, the target steering angle θh2 is set to the value obtained by adding the correction amount C to the target steering angle θh2 in normal conditions. in this way,
When lateral G is acting, the target steering angle θh2 is set in consideration of the influence of this lateral G.

FIG. 11 shows the control operation for setting the target steering angle θh according to changes in road surface conditions. First, in step S4', a signal from the wiper switch 25 is input, and in step S41', the control operation shown in FIG. The correction scale is calculated from the map showing the relationship between the wiper operating state and the corresponding correction scale, and in step 842', the target steering angle θh2 is set to the value obtained by subtracting the correction scale from the target steering angle θh2 in normal conditions.
Set. In this way, when the wiper is activated, that is, when the road surface frictional resistance is low, the target θh2 is set so as to suppress the hypersensitive behavior of the vehicle.

Here, based on flowchart 1~ shown in FIG.
The first by the insensitive joint 13. Second shaft 10a, 10
To explain the control operation for varying the allowable range of relative rotation between
In step T2, the vehicle speed V is input based on the signal from the vehicle speed sensor 21, and in step T2 it is determined whether there is an abnormality in the system of the steering device 1. If there is a system abnormality, this control will not be executed and the above-mentioned 1. The second shafts 10a and 10b are controlled so as not to rotate relative to each other. If there is no abnormality in the system, the vehicle speed V becomes ■ in step T3. (30km/h), and if it is V〈■o, in step T4, the first. Second shaft 10
The relative rotation tolerance range of a and 10b, that is, the dead zone area is L
Hydraulic cylinder 16 is driven so that o. Further, when it is determined NO in step T3, it is determined in step T5 whether the vehicle speed ■ is lower than v, (60 h/h), and if ■ is 1, in step T6 the dead zone area is Ll( Hydraulic cylinder 16 so that LO>Ll>
to drive. Furthermore, when the determination is No in step T5, the vehicle speed V is changed to V2 (80 wt./cm) in step T7.
'h) If it is 2, in step T8 the dead zone area is L 2 (L 1>
The hydraulic cylinder 16 is driven so that L 2 ).

Further, when the determination in step T7 is NO, step T9 determines that the dead zone area is L3 (L2 >
The hydraulic cylinder 16 is driven so that L3) is achieved.

In this way, control is performed so that the dead zone region is narrowed as the vehicle speed increases.

Note that when the brake is depressed, the control unit 20 executes the following control operation in priority to the control shown in FIG. 13. That is, as shown in FIG. 14, the control unit 20 determines whether the brake is depressed based on the signal from the brake switch 22 in step T1', and if YES, the control unit 20 advances to step T2'.
Then, it is determined whether the deceleration of the vehicle determined based on the signal from the vehicle speed sensor 21 is greater than or equal to a predetermined value, and if YES, the dead zone area is changed in step T'3. shall be. That is, when the brake is fully depressed, the front wheels 4.4 can be appropriately steered by the hydraulic cylinder 7.
The dead zone area is set to be large.

Next, the control operation of the electromagnetic brake by the control unit 20, which is a characteristic part of this embodiment, will be explained based on the flowchart shown in FIG.
1, 1st. The steering angle θ of the first shaft 10a to which the handle 8 is connected is determined by the signal from the second steering angle sensor 14.15.
h! Then, the steering angle θh2 of the second shaft 10b is input, and in step P2, it is determined whether the steering wheel 8 is in the neutral state based on the respective steering angles θh1 and θh2. If YES, in step P3, from the map showing the relationship between the vehicle speed V and the brake current I output accordingly in FIG. 1
Output for 9. Further, when it is determined in step P2 that the steering wheel 8 is not in the neutral state, it is determined in step P4 whether the deviation from each of the steering angles θh and θh2 is large, and if YES, in step P5, Outputs a brake current of I-I+0.21.

Furthermore, in step P4, the front steering angle θh, θh1
If it is determined that the deviation is not large, it is determined in step P6 whether the behavior of the vehicle is in an extremely unstable countersteering state, and if YES, a brake current of I=I+0.4I is output. Furthermore, when it is determined in step P6 that countersteering is not in progress, that is, when the deviations of the front steering angles θhl and θh2 are extremely small, the steering wheel 8 is actually steered, and the front wheels 4,
Assuming that 4 is properly steered and 5, I=
Outputs I-0 and 2I brake currents.

In this way, the flow t corresponding to the vehicle speed V is output, thereby imparting a predetermined rotational resistance to the steering wheel 8, improving the operational feeling of the steering wheel 8, and increasing the vehicle speed V. Accordingly, the brake current (2) is increased, and the braking force, that is, the rotational resistance acting on the handlebar 8, is increased in accordance with the vehicle speed, and the straight-line stability during high-speed driving can be further improved.

Also, 1st. If the deviation between the steering angles θh1 and θh2 of the second shaft is large, the brake current (2) will be increased, and a larger rotational resistance will be applied to the handle 8. In other words, the reason for the large deviation between the front angles θh1 and θh2 is thought to be that the driver's steering wheel operation is not appropriate. Therefore, by increasing the brake current I and applying a large rotational resistance to the steering wheel 8, , it is possible to reliably prevent unnecessary steering wheel operations by the driver.

Furthermore, during countersteering, even greater rotational resistance is applied to the steering wheel 8 than when the deviation is large, thereby preventing the driver from inappropriately operating the steering wheel.
The front wheels 4, 4 are designed to allow good steering.

In addition, as shown in FIGS. 17 and 18, both shafts 50a are divided into a first shaft 50a to which a handle (not shown) is connected, and a second shaft 50b to which a rack and binion mechanism (not shown) is connected. , 50bftH and the rotation regulating means for applying rotational resistance to the first shaft 50a may be configured as follows. That is, the first
An insensitive joint 53 is constituted by a bin member 51 fixed to the shaft 50a and a notch hole 52 formed in the second shaft 50b so that the bin member 51 can be rotated within a predetermined range. At the same time, one end is fixed to the second shaft 50b via a fixing member 54, and the other end is fixed to the first shaft 50b.
A rotation regulating means is constituted by a torsion bar 55 fixed to the shaft 50a and a rubber bush 56 interposed between the outer peripheral surface of the torsion bar 55 and the inner peripheral surface of the second shaft 50b. According to this, relative rotation between the first shaft 50a and the second shaft 50b is allowed within the rotation range of the bin member 51. Further, since the torsion bar 55 and the rubber bush 56 are provided between the first shaft 50a and the second shaft 50b, when the deviation in the rotational direction between the two shafts 50a and 50b is small, the rubber bush 56 is Frictional resistance acts as rotational resistance between the two shafts 50a and 50b, and the first shaft 50a and the second shaft 50
When the deviation between the shafts 50a and 50brr increases, the spring force (torsional resistance) of the torsion bar 55 increases.
It will act as rotational resistance on I, and in this way,
With a relatively simple configuration, both the shafts 50a, 50
Since the required rotational resistance is applied to the first
The operational feeling of the handle connected to the shaft 50a can be improved.

In this embodiment, a sleeve 57 is spline-fitted to the outer periphery of the shaft end of the second shaft 50b, and a spline 58 that meshes with the sleeve 57 is formed on the first shaft 50a. When the sleeve 57 is biased by the coil spring 59, and is held in the position shown in FIG. 2 by the regulating member 60, and the regulating member 6o is moved as shown by the chain line, , the sleeve 57 moves and the sleeve 57 moves to the first position. It is fitted onto the second shafts 5a and 50b, and is stroked so as to restrict the relative rotation of the two shafts 50a and 50b.

(Effects of the Invention) As described above, according to the first invention, rotational resistance is applied to the first shaft to which the steering wheel is connected by the rotation regulating means. Even if the shaft is relatively rotatable,
A required amount of rotational resistance is applied to the steering wheel connected to the first shaft, which improves the operational feeling of the steering wheel and also ensures that unnecessary steering operations that occur because the steering wheel is too light are avoided. This can be prevented and the running stability of the vehicle can be improved.

Further, according to the second invention, since the rotation regulating means for applying rotational resistance to the first shaft to which the steering wheel is connected is constituted by an electromagnetic brake, the amount of electricity applied to the electromagnetic brake can be controlled to brake the first shaft. By adjusting the force, it is possible to vary the rotational resistance that acts on the steering wheel connected to the first shaft. This allows, for example, to vary the rotational resistance that acts on the steering wheel appropriately depending on the driving condition of the vehicle. Can be adjusted.

Furthermore, according to the third aspect of the invention, since the rotation control means is provided for controlling the operation of the electromagnetic brake as the rotation regulating means in accordance with at least the vehicle speed, for example, the braking force of the electromagnetic brake can be adjusted in response to an increase in the vehicle speed. By increasing this, it is possible to gradually increase the rotational resistance acting on the steering wheel when transitioning from low-speed driving to high-speed driving, thereby further improving straight-line stability, especially during high-speed driving.

Furthermore, according to the fourth invention, since the rotation regulating means is constituted by the torsion bar and the elastic body provided between the first shaft and the second shaft, deviation in the rotational direction between the two shafts is prevented. is small, the frictional resistance of the elastic body acts as rotational resistance between both shafts, and the first
If the deviation between the shaft and the second shaft increases,
The spring force (torsional resistance) of the torsion bar acts as a rotational resistance between the two shafts, making it possible to apply the required rotational resistance between the two shafts with a relatively simple configuration.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is an overall system diagram of a vehicle steering device according to this embodiment, and FIG. 2 shows the configuration of an insensitive joint and a rotation regulating means that constitute the steering device. 3 is a sectional view taken along the line A-A in FIG. 2, FIG. 4 is a flowchart showing the front wheel steering control operation, and FIG. 5 is a diagram showing the target steering angle according to the steering speed. FIG. 6 is a map showing the relationship between the steering speed and steering angle correction amount; FIG. 7 is a flowchart of the control operation to set the target steering angle according to the yaw rate; FIG.
The figure is a map showing the relationship between the yaw rate and the steering angle correction amount, FIG. 9 is a flowchart showing the control operation for setting the target steering angle according to the lateral G, and FIG. 10 is the relationship between the lateral G and the steering angle correction amount. A map showing the relationship, FIG. 11 is a flowchart showing the control operation for setting the target steering angle according to the road surface condition, and FIG. 12 is a map showing the relationship between the operating state of the wiper switch and the steering angle correction amount. , 14 is a flowchart of dead zone control, 15th flowchart of electromagnetic brake control,
Figure 16 is a map showing the relationship between vehicle speed and brake current.
FIG. 17 is a cross-sectional view of the main parts showing the structure of the insensitive joint and rotation regulating means of another embodiment, and FIG. 18 is B--B in FIG.
It is a sectional view taken along the B line. 1... Steering device, 7... Actuator (hydraulic cylinder), 8... Steering wheel (handle), 9
...Gear mechanism (rack & binion mechanism), 10...
Steering shaft, 10a...first shaft, 1
(]b...Second shaft, 13...Insensitive joint, 1
4.15... 1st. 2nd steering angle sensor, 19,55.5
6... Rotation regulating means (19... electromagnetic brake, 55...
...Torsion bar, 56...Rubber bushing), 2
0... Control means, rotation regulating means (control unit).

Claims (4)

[Claims] (1) A steering device for a vehicle that converts the rotational displacement of a steering wheel into a displacement in the vehicle width direction via a gear mechanism to steer the front wheels, wherein the steering shaft between the steering wheel and the gear mechanism is It is divided into a first shaft on the steering wheel side and a second shaft on the gear mechanism side, and these first and second shafts are connected by an insensitive joint that allows relative rotation of both shafts, a first steering angle sensor that detects the rotation angle of the first shaft; a second steering angle sensor that detects the rotation angle of the second shaft; an actuator that steers the front wheels; and the first and second steering wheels. control means for controlling the operation of the actuator within an allowable range of relative rotation between the first and second shafts according to the running condition based on a signal from the angle sensor; A steering device for a vehicle, characterized in that it is equipped with a rotation regulating means. (2) A steering device for a vehicle that converts rotational displacement of a steering wheel into displacement in the vehicle width direction via a gear mechanism to steer the front wheels, wherein the steering shaft between the steering wheel and the gear mechanism is It is divided into a first shaft on the steering wheel side and a second shaft on the gear mechanism side, and these first and second shafts are connected by an insensitive joint that allows relative rotation of both shafts, A first shaft that detects the rotation angle of the first shaft.
a steering angle sensor, a second steering angle sensor that detects the rotation angle of the second shaft, an actuator that steers the front wheels, and a steering wheel according to the driving state based on signals from the first and second steering angle sensors. and a control means for controlling the operation of the actuator within an allowable relative rotation range of the first and second shafts, and further comprising a rotation regulating means comprising an electromagnetic brake for applying rotational resistance to the first shaft. A vehicle steering device characterized by: (3) A steering device for a vehicle that converts the rotational displacement of a steering wheel into a displacement in the vehicle width direction via a gear device to steer the front wheels, wherein the steering shaft between the steering wheel and the gear mechanism is The shaft is divided into a first shaft on the steering wheel side and a second shaft on the gear device side, and the first and second shafts are connected by an insensitive joint that allows relative rotation of both shafts. , a first steering angle sensor that detects the rotation angle of the first shaft, a second steering angle sensor that detects the rotation angle of the second shaft, an actuator that steers the front wheels, and the first and second steering angle sensors. control means for controlling the operation of the actuator within an allowable range of relative rotation of the first and second shafts according to the driving state based on a signal from the steering angle sensor; 1. A steering system for a vehicle, comprising: a rotation regulating means made of an electromagnetic brake that applies a rotation regulating means; and a rotation controlling means controlling the operation of the rotation regulating means according to at least vehicle speed. (4) A steering device for a vehicle that converts the rotational displacement of a steering wheel into a displacement in the vehicle width direction via a gear device to steer the front wheels, wherein the steering shaft between the steering wheel and the gear device is It is divided into a first shaft on the steering wheel side and a second shaft on the gear mechanism side, and these first and second shafts are connected by an insensitive joint that allows relative rotation of both shafts, A first shaft that detects the rotation angle of the first shaft.
a steering angle sensor, a second steering angle sensor that detects the rotation angle of the second shaft, an actuator that steers the front wheels, and a steering wheel according to the driving state based on signals from the first and second steering angle sensors. control means for controlling the operation of the actuator within an allowable range of relative rotation of the first and second shafts, and further comprising a torsion bar and an elastic body provided between the first and second shafts. A steering device for a vehicle, comprising: rotation regulating means for applying rotational resistance between the two shafts.