JP2001114118A - Vehicle steering system - Google Patents

Abstract

(57) [Problem] To provide a steering device in which a steering side of a steering wheel and a steered side of a wheel are separated from each other, the steering wheel can be reliably returned to a neutral position, and steering of the steering wheel is performed. To generate a reaction force according to the angle to give the driver a comfortable steering feeling. SOLUTION: A steering direction and a steering angle of a steering wheel 11 are detected, and a detection signal is sent to a steering controller 10.
The turning direction and the turning angle of the wheel 19 are determined in consideration of the vehicle speed, and the wheel 19 is turned by the electric motor 14 based on this. An eccentric disk 37 that rotates in accordance with the rotation of the shaft 30 of the steering wheel 11 is provided, and a swing arm 4 having a tip roller 41 that contacts the eccentric disk 37.
Numeral 0 is swingably provided, and the distal end roller 41 of the swing arm 40 is urged against the eccentric disk 37 by a compression spring 44.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering apparatus in which the steering side of a steering wheel and the steered side of a wheel are separated from each other. The present invention relates to a vehicle steering device capable of generating a reaction force according to a steering angle of the vehicle and providing a comfortable steering feeling to a driver.

[0002]

2. Description of the Related Art Generally, as a steering device for a motor vehicle, a steering wheel is steered, a steering shaft mechanically connected to the steering wheel is rotated, and the wheel is steered via a tie rod or the like. I have. However, in recent years, the ITS (Interigent Transport System)
s), AHS (Automated Highway Systems), etc., to detect the steering direction and steering angle of the steering wheel, input this detection signal to the controller, and take into account other factors such as vehicle speed. There is known a steering device in which a steering direction and a steering angle are determined, and the wheels are steered by an electric motor based on the steering direction and the steering side of the steering wheel is separated from the steering side of the wheels. I have.

[0003] In such a separate type steering device, a steering wheel is attached to a shaft of a steering hole in order to give a driver a steering feeling as if the steering wheel and the wheel were mechanically connected. There is provided a reaction force generating device that functions to return to a neutral position and to generate a reaction force according to the steering angle of the steering wheel.

For example, in Japanese Patent No. 2814375,
As shown in FIG. 17, a gear 2 is meshed with a shaft 1 of a steering wheel, and a heart-shaped eccentric disk 3 is provided coaxially with the gear 2. A roller 7 of a piston 6 slidably provided in a cylinder 5 is in contact with a notch portion 4 of the eccentric disk 3, and a compression spring 9 is interposed on a flange 8 of the piston 6. is there. The compression spring 9 urges the piston 6 toward the eccentric disk 3 so that the roller 7 of the piston 6 always rotates the eccentric disk 3.
Is pressed against the notch 4.

With this configuration, when the steering wheel is rotated left and right, the eccentric disk 3 rotates eccentrically about the gear 2 and the piston 6 slides to the left in FIG. Since the roller 7 of the piston 6 is always pressed against the eccentric disk 3 by the compression spring 9, the eccentric disk 3 is returned to the original position (the position shown in the drawing) where the eccentric amount is the least. This causes the steering wheel to return to the neutral position. As a result, the driver can obtain a neutral feeling of the steering wheel.

Further, as the steering angle of the steering wheel increases, the amount of eccentricity of the eccentric disk 3 increases, and accordingly, the amount of sliding of the piston 6 to the left in FIG. 17 increases. As a result, the roller 7 by the compression spring 9
And the pressing force on the eccentric disk 3 increases, and the reaction force for returning the eccentric disk 3 to the original position (that is, the reaction force for returning the steering wheel to the neutral position) increases. Thus, the driver can experience a comfortable steering feeling as if the steering wheel and the wheels are mechanically connected by experiencing the reaction force as steering torque.

[0007]

However, in the reaction force generating device of the separation type steering device disclosed in the above-mentioned publication (FIG. 17), the relationship between the piston 6 and the eccentric disk 3 is referred to as "direct" in cam terms. Since the piston 6 reciprocates linearly with respect to the eccentric disk 3, a bending force acts on the piston 6 when a reaction force is generated in the eccentric disk 3 in the circumferential direction. Due to this bending load, sliding friction is generated in a direction (axial direction) in which the urging force of the compression spring 9 is canceled.

The pushing angle of the eccentric disk 3 is defined as the angle between the common normal at the point of contact between the roller 7 and the eccentric disk 3 and the direction of movement of the piston 6, and this pushing angle is The smaller the value, the better the transmission efficiency of the force. In the case of the "linear follower", the limit value is about 30 degrees.

For example, in the case of FIG. 17, when the steering wheel is started to be turned from the neutral position, the roller 7 of the piston 6 presses the notch 4 of the eccentric disk 3, and the contour of the notch 4 is Since the eccentric disk 3 rises rapidly, the pushing angle of the eccentric disk 3 is large, and is about 30 degrees or more of the above-mentioned limit value.

As a result, as the pushing angle of the eccentric disk 3 increases, the sliding friction force generated by the bending load increases. Therefore, when the steering wheel is started to be turned from the neutral position, the large sliding friction force may cause the piston 6 to not slide smoothly, and a comfortable steering feeling may not be obtained. There is a possibility that the force exceeds the urging force of the compression spring 9, and in this case, the piston 6 hardly slides, which may hinder the return of the steering wheel to the neutral position and the generation of a reaction force. .

When the steering wheel is turned back, the eccentric disk 3 is reversed and the sliding direction of the piston 6 is also reversed. At this time, if there is "play" between the piston 6 and the cylinder 5, noise is generated. In some cases, the clearance between the piston 6 and the cylinder 5 must be strictly controlled because of the possibility of causing a shock.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances. Even in a steering device in which the steering side of the steering wheel and the steered side of the wheel are separated, the neutral position of the steering wheel is maintained. It is an object of the present invention to provide a steering apparatus for a vehicle that can reliably return to the steering wheel and generate a reaction force according to a steering angle of a steering wheel to provide a driver with a comfortable steering feeling.

[0013]

In order to achieve the above object, a vehicular steering apparatus according to the present invention detects a steering direction and a steering angle of a steering wheel, inputs the detection signal to a controller, and outputs a vehicle speed. In consideration of the above, the steering direction and the steering angle of the wheels are determined, and the vehicle steering device is configured to steer the wheels by the electric motor based on the determined steering direction and the steering angle.
An eccentric disc that rotates in accordance with the rotation of the steering wheel shaft, a swing arm that has a tip that abuts the eccentric disc, and that is swingably provided; Urging means for urging the swing arm so as to press the distal end portion.

Thus, according to claim 1 of the present invention,
The tip of the swing arm is pressed against the eccentric disk rotating in response to the rotation of the shaft of the steering wheel by a biasing means. Therefore, when the steering wheel is rotated left and right, the eccentric disk rotates eccentrically, and the tip of the swing arm tends to be pushed back. However, since the tip of the swing arm is pressed against the eccentric disk by the urging means, the eccentric disk attempts to return to the original position (notch portion) where the eccentric amount is the least. A reaction force is generated, and by this reaction force, the steering wheel can be reliably returned to the neutral position, and the driver can obtain a neutral feeling of the steering wheel.

Further, as the steering angle of the steering wheel increases, the amount of eccentricity of the eccentric disk increases, and accordingly, the amount by which the tip of the swing arm is pushed back increases. As a result, the pressing force from the tip of the swing arm to the eccentric disk by the urging means is increased, and a reaction force for returning the eccentric disk to the original position (notch portion) (that is, the steering wheel is neutralized) The reaction force for returning to the position) increases. Thus, a reaction force corresponding to the steering angle of the steering wheel can be generated, and the driver can obtain a comfortable steering feeling by experiencing the reaction force.

Further, since the tip of the swing arm is pressed against the eccentric disk by the urging means, the relationship between the eccentric disk and the swing arm is constituted by a "swing follower" in cam terms. be able to. Therefore, when a reaction force is generated in the eccentric disk in the circumferential direction, even if a bending load acts on the swing arm, almost no friction force is generated as in the case of the conventional piston of the "linear follower". Therefore, the operation of the swing arm is not hindered.

Further, when the steering wheel is turned back, the eccentric disk is inverted and the swinging direction of the swing arm is also inverted. Does not affect the reaction force generation of the eccentric disk, and it is not necessary to strictly manage the gap as in the related art.

In the steering apparatus for a vehicle according to a second aspect of the present invention, the eccentric disk has a notch at a position where the amount of eccentricity is least, and the swing arm has a notch at a tip end thereof. It has a rotatable roller, and the radius (R1) of the notch is set to be larger than the radius (R2) of the roller (R1> R2).

Thus, according to claim 2 of the present invention,
The radius (R1) of the notch is set to be larger than the radius (R2) of the roller (R1> R2), so that the roller contacts the notch at one contact point. Therefore, when the roller returns to the notch from the state in which the steering wheel is rotated left and right, the roller is in contact with one contact point at a place other than the notch, and even if the roller enters the notch, Since the contact is made at one contact point, no stamping sound is generated, and the driver does not feel discomfort due to the stamping sound.

Further, in the vehicle steering apparatus according to a third aspect of the present invention, the swing arm has a rotatable roller at a tip end thereof, and an outer peripheral surface of the eccentric disk and a roller of the roller. A cushioning member is provided on both or one of the outer peripheral surfaces.

Thus, according to claim 3 of the present invention,
On both the outer peripheral surface of the eccentric disk and the outer peripheral surface of the roller,
Or, since one of them is provided with a buffer member,
Avoid metal-to-metal contact between the eccentric disk and roller,
The noise between the two is prevented, thereby preventing the driver from feeling uncomfortable. When the roller returns to the notch portion of the eccentric disk, there is a possibility that the stamping sound is particularly likely to occur. However, according to the third aspect, the roller returns to the notch portion by the buffer member. The stamping sound at the time of performing can also be effectively prevented.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a vehicle steering system according to an embodiment of the present invention will be described with reference to the drawings. (First Embodiment: Claim 1) FIG. 1 is a block diagram of a vehicle steering system according to a first embodiment of the present invention, and FIG. 2 is a block diagram of the steering system shown in FIG. FIG. 3 is a longitudinal sectional view of the force generating device, FIG. 3 is a partially cutaway bottom view of the reaction force generating device of the steering device shown in FIG. 1 as viewed from below, and FIG.
FIG. 5A is a cross-sectional view taken along the line AA of FIG.
4 is a graph illustrating a relationship between a steering angle and a reaction torque of the reaction force generator according to the embodiment.

As shown in FIG. 1, in the vehicle steering system,
The steering side of the steering wheel and the steered side of the wheels are separated, and a steering controller 10 is provided between the two.

On the steering side, a steering wheel 11
An angle sensor 12 for detecting a steering direction and a steering angle of the steering wheel 11, and a reaction force for returning the steering wheel 11 to the neutral position and generating a reaction force according to the steering angle of the steering wheel 11. A generator 13 is provided.

On the steered side, there is provided an electric motor 14 that is driven to rotate based on an instruction signal from the steering controller 10, and this electric motor 14 is provided via a speed reducer 15.
It is connected to a conversion mechanism 17 that converts the rotation of the electric motor 14 into a linear motion of the steering shaft 16. Steering shaft 1 of conversion mechanism 17
6 is a wheel 1 via a tie rod 18 or a knuckle arm.
9. The speed reducer 15 is provided with a position detection sensor 20 including an encoder for detecting the actual turning direction and the turning angle of the wheels 19.

The steering controller 10 includes the angle sensor 12, the position detection sensor 20, and the speed sensor 2
1 is input. The steering controller 10 controls the wheel 1 based on the input information of the steering direction and the steering angle, the speed information, and the information of other elements.
The turning direction and turning angle of No. 9 are determined, and this signal is output to the electric motor 14. Accordingly, when the electric motor 14 rotates, the steering shaft 16 linearly moves by the conversion mechanism 17, and the tie rod 18 and the knuckle arm operate to steer the wheels 19.

Next, as shown in FIG.
In 3, a shaft 30 connected to the steering wheel 11 is rotatably supported by bearings 32 and 33 in a column 31. In the illustrated example, the angle sensor 12
Is attached to the lower end of the shaft 30.

A gear box 34 is provided below the shaft 30, and a small gear 35 is fixed below the shaft 30. The small gear 35 is attached to the small gear 35 as shown in FIGS. The large gear 36 is meshed with the small gear 35 and the large gear 36 at a gear ratio of, for example, 1: 3.

As shown in FIGS. 3 and 4, a heart-shaped eccentric disk (cam) 37 having a notch 37a is provided coaxially with the large gear 36, and the maximum rotation angle of the eccentric disk 37 is provided. Is ± 180 °, but is actually ± 180 ° or less because the rotation angle stopper 38 is provided on the gear box 34 and the rotation angle stopper projection 38 ′ is provided on the eccentric disk 37.

A swing center G is provided below the gear box 34.
And a swing arm 40 configured to be swingable. A roller 41 is provided at the tip of the swing arm 40,
It is pressed against the eccentric disk 37.

On the base end side of the swing arm 40, an adjustment bolt 42 is provided in the gear box 34 so as to be movable in the axial direction.
3 is provided slidably. A compression spring 44 is interposed between the adjustment bolt 42 and the spacer 43. The compression spring 44 separates the spacer 43 from the swing arm 4
The roller 45 at the base end of the "0" is pressed.

Therefore, the compression spring 44 is
4, the base end of the swinging dome 40 is constantly urged in the counterclockwise direction in FIG. 4 so that the roller 41 at the tip end of the swinging arm 40 is displaced by the eccentric disk 37.
Is constantly pressed. The pressing force of the compression spring 44 can be adjusted by loosening the lock nut 42 'and changing the position of the adjustment bolt 42.

With this configuration, when the steering wheel 11 is rotated left and right, the eccentric disk 37 is rotated via the shaft 30, the small gear 35 and the large gear 36.
Is eccentrically rotated, and the roller 4 at the tip end of the swing arm 40 is rotated.
1 is about to be pushed back. However, this swing arm 4
0 roller 41 is compressed by eccentric disk 3 by compression spring 44.
7, the eccentric disk 37 is placed at the original position (notch portion 37) having the least amount of eccentricity.
a, the illustrated position), the steering wheel 11 can be surely returned to the neutral position by the reaction force, and the driver can feel the neutral feeling of the steering wheel 11. Obtainable.

Further, as the steering angle of the steering wheel 11 increases, the amount of eccentricity of the eccentric disk 37 increases, and accordingly, the amount by which the roller 41 at the tip end of the swing arm 40 is pushed back increases. . as a result,
The pressing force from the roller 41 of the swing arm 40 to the eccentric disk 37 by the compression spring 44 increases, and a reaction force (that is, the steering wheel 11) that returns the eccentric disk 37 to the original position (notch portion 37 a). The reaction force for returning to the neutral position increases. Thereby, a reaction force according to the steering angle of the steering wheel 11 can be generated, and the driver can experience the reaction force by
A comfortable steering feeling can be obtained.

In particular, in this embodiment, the eccentric disk 3
As shown in FIG. 5 (a), a portion near the neutral position (a notch portion 37a of the eccentric disk 37, this portion is an area where the driver's steering feeling is sensitive) In (2), the reaction torque is rapidly increased, and the reaction torque is slightly increased at a position where the steering angle is large. As described above, since the non-linear characteristics can be obtained, the driver can obtain a more comfortable steering feeling as compared with the case of the linear characteristics.

Further, since the distal end of the swing arm 40 is pressed against the eccentric disk 37 by the compression spring 44,
The relationship between the eccentric disk 37 and the swing arm 40 can be configured as a "swing follower" in cam terms. for that reason,
When a reaction force is generated in the eccentric disk 37 in the circumferential direction, even if a bending load is applied to the swing arm 40, almost no frictional force is generated as in the case of the conventional “direct acting follower” piston. Therefore, the operation of the swing arm 40 is not hindered. (Second Embodiment: Claim 1) Next, a vehicle steering device according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 5B is a graph showing the relationship between the steering angle and the reaction torque of the reaction force generator according to the second embodiment, and FIG. 6 is a vehicle steering device according to the second embodiment. It is sectional drawing of the reaction-force generator of this.

In the first embodiment shown in FIGS. 1 to 4, the heart-shaped eccentric disk 37 is formed symmetrically, but the pressing force of the swing arm 40 is eccentric from only one side. As shown in FIG. 5B, the characteristic of the reaction force generated on the eccentric disk 37 because it acts on the disk 37 may be asymmetric between right rotation and left rotation.

Although the reaction force characteristics are asymmetric, there is almost no left-right difference in the small rotation angle range where the steering feeling is easily felt, and the left-right difference gradually increases in the large angle range. Hardly noticeable in the hands of the elderly and negligible.

In some cases, however, it is necessary to substantially completely eliminate such a difference between the right and left reaction force characteristics. In the second embodiment, as shown in FIG.
7 are formed asymmetrically. Accordingly, even when the pressing force of the swing arm 40 acts on the eccentric disk 37 from only one side, the reaction force characteristic of the eccentric disk 37 is left-right symmetric whether clockwise or counterclockwise. (Third Embodiment: Claim 1) Next, FIGS.
A vehicle steering device according to a third embodiment of the present invention will be described with reference to FIG. FIG. 7 is a longitudinal sectional view of a reaction force generating device of a vehicle steering device according to a third embodiment of the present invention, and FIG. 8 shows the reaction force generating device of the steering device shown in FIG. 9 is a cross-sectional view taken along line AA of FIG. 7, FIG. 10 is a cross-sectional view taken along line BB of FIG. 7, and FIG. FIG. 11A is a graph illustrating a relationship between a steering angle and a steering torque of the reaction force generator according to the third embodiment.

In the third embodiment, the eccentric disk 37
In addition to a mechanical reaction force generating mechanism by the swing arm 40, an electric reaction force generating mechanism by a reaction motor (DC motor) 52 is provided.

As shown in FIG. 7, a worm wheel 50 is provided on the shaft 30, and a worm 51 is engaged with the worm wheel 50. As shown in FIG. 9, a reaction force motor (DC motor) 52 is connected to the worm 51 via a clutch 53.

Further, the steering controller 10 determines a required reaction force based on the speed information input from the speed sensor 21 and the road surface reaction force and the axial force of the tie rod 18 input from a torque detection sensor (not shown). Is calculated, a reaction force instruction signal is transmitted to the reaction force motor 52. Further, the steering controller 10 includes the reaction force motor 5
2 or when the steering controller 10 breaks down, an instruction signal for disconnecting the reaction motor 52 is transmitted to the clutch 53.
To be sent to

The reaction force of the reaction motor 52 takes into account the speed information, the road surface reaction force and the axial force of the tie rod 24 as described above, and simulates the road surface reaction force actually applied to the wheels 25. It is a reflection.

The bearings 56 and 57 of the worm 51 are
It is urged in the axial direction by an adjust bolt 59 via a spacer 58, and by adjusting the adjust bolt 59 by loosening the lock nut 59 ', the bearing 56,
57 play is prevented.

In the third embodiment, as shown in FIG. 11A, the reaction force generated by the mechanical reaction force generating mechanism of the eccentric disk 37 and the swing arm 40 and the reaction force of the reaction motor 52 A predetermined ideal steering torque is obtained by the sum of the reaction force generated by the electric reaction force generating mechanism and the reaction force. As described above, at the time of normal steering, the shortage of the mechanical reaction force is supplemented by the electric reaction force to obtain an ideal steering torque.

Therefore, when the reaction motor 52 or the steering controller 10 breaks down and the clutch 53 of the reaction motor 52 is disengaged, the mechanical reaction force generating mechanism of the eccentric disk 37 and the swing arm 40 is disengaged. The steering wheel 11 is returned to the neutral position by the reaction force to fulfill the fail-safe function.

When the mechanical reaction force generating mechanism fulfills the fail-safe function, the reaction force generated by the mechanical reaction force generating mechanism, as shown in FIG.
The steering wheel 1
1 so that it can return to neutral immediately.
As compared with the case of linear characteristics, the safety during high-speed running with a small steering angle can be significantly increased.

As a modification of the third embodiment,
As shown in FIG. 11B, a reaction force greater than a predetermined ideal steering torque is generated by the mechanical reaction force generation mechanism of the eccentric disk 37 and the swing arm 40, and the reaction motor 52 The electric reaction force generating mechanism may generate a reaction force for reducing the large reaction force of the mechanical reaction force generation mechanism, and thereby apply a predetermined ideal steering torque to the steering wheel 11. .

In this case, even if the reaction force by the reaction motor 52 suddenly disappears, the reaction force reduces the large reaction force of the mechanical reaction force generating mechanism to a predetermined ideal steering torque. When the clutch 53 is disengaged, the driver suddenly feels heavier in steering of the steering wheel 11 due to the large reaction force of the mechanical reaction force generating mechanism. When the motor 52 or the like breaks down, it is possible to eliminate the discomfort of the driver such as suddenly feeling the steering of the steering wheel 11 lightly.
It is useful in high-speed driving.

In the second embodiment, a measure is taken to make the contour of the eccentric disk 37 bilaterally asymmetric in order to eliminate the left-right asymmetry of the reaction force characteristic of the eccentric disk 37. In the embodiment, by making the reaction force characteristics of the reaction force motor 52 asymmetric, the reaction force characteristics of the sum of the eccentric disk 37 and the reaction force motor 52 can be made bilaterally symmetric. (Fourth Embodiment: Claim 1) Next, FIGS.
With reference to FIG. 4, a vehicle steering device according to a fourth embodiment of the present invention will be described. FIG. 12 is a longitudinal sectional view of a reaction force generating device of a vehicle steering system according to a fourth embodiment of the present invention, and FIG. 13 is a sectional view taken along line AA of FIG. FIG. 14 is a sectional view taken along line BB of FIG.

In the first to third embodiments, the plurality of gears 3 are mounted on the shaft 30 of the steering wheel 11.
The eccentric disk 37 is provided through the intermediary of the steering wheel 11 and the steering wheel 11 in the fourth embodiment.
A shaft 30 is provided with an eccentric disk 37 directly. By eliminating the plurality of gears 35 and 36, manufacturing costs can be reduced.

In this case, the steering wheel 1
Although the rotation angle of 1 is ± 180 ° or less, the steering angle of the wheel 19 is determined by the steering controller 10 in consideration of the vehicle speed and the like because the steering device is a steering device in which the steering side and the steering side are separated. And can be set freely.

Other functions and effects are the same as those of the first to third embodiments. (Fifth Embodiment: Claim 2) Next, a vehicle steering system according to a fifth embodiment of the present invention will be described with reference to FIG. FIG. 15A is an enlarged view of the eccentric disk and the roller, wherein the radius (R1) of the notch portion of the eccentric disk is equal to the radius (R2) of the roller or the radius (R2) of the roller.
FIG. 15 shows a case where the value is set smaller (R1 ≦ R2).
(B) shows a case where the radius (R1) of the notch portion of the eccentric disk is set to be larger than the radius (R2) of the roller (R1> R2) according to the fifth embodiment of the present invention.

In the first to fourth embodiments described above, as shown in FIGS. 4, 6, 10 and 14, the roller 41 of the swing arm 40 is moved by the compression spring 44 to the eccentric disk 37. When the steering wheel 11 is rotated left and right, the eccentric disk 37 is placed at the original position (notch portion 37) having the least amount of eccentricity.
a, the illustrated position), the steering wheel 11 can be reliably returned to the neutral position by the reaction force.

In other words, the notch 37a of the eccentric disc 37 defines the neutral position of the steering wheel where the roller 41 biased by the compression spring 44 returns when the steering wheel 11 is rotated left and right. Plays a role.

FIG. 15 shows the relationship between the radius (R1) of the notch 37a and the radius (R2) of the roller 41.
As shown in (a), when the radius (R1) of the notch portion 37a is set to be smaller than the radius (R2) of the roller 41 (R1 <R2), the roller 41 contacts the notch portion 37a with two contact points. In contact.

Therefore, when the roller 41 returns to the notch portion 37a from the state in which the steering wheel 11 is rotated left and right, the roller 41 is in contact with one contact point except for the notch portion 37a. Notch part 37a
Immediately after entering the location, the two contact points come into contact with each other, and at that time, an imprinting sound (click noise) is generated. Since this stamping sound is transmitted to the driver via the steering wheel, the driver may feel uncomfortable.

For this reason, in the fifth embodiment, as shown in FIG. 15B, the radius (R1) of the notch 37a is larger than the radius (R2) of the roller 41 (R1).
> R2) so that the roller 41 comes into contact with the notch 37a at one contact point.

Therefore, when the roller 41 returns to the notch portion 37a from the state in which the steering wheel 11 is rotated left and right, the roller 41 is in contact with one point other than the notch portion 37a at one contact point. Even if the vehicle enters the location of the portion 37a, it makes contact at one contact point, so that the driving sound does not generate the driving sound as described above, and the driving sound gives the driver discomfort. There is no such thing. (Sixth Embodiment: Claim 3) Next, a vehicle steering apparatus according to a sixth embodiment (claim 3) of the present invention will be described with reference to FIG. FIG. 16 is a sectional view of a vehicle steering system according to a sixth embodiment of the present invention, and is a diagram corresponding to FIG. 10 of the third embodiment.

In the sixth embodiment, the eccentric disk 37
A cushioning member 37b is provided on the outer peripheral surface of the roller 41, and a cushioning member 41b is provided on the outer peripheral surface of the roller 41. This avoids contact between the metal of the eccentric disk 37 and the roller 41, thereby preventing the squealing noise (snap noise) between the two and preventing the driver from feeling uncomfortable. Note that the roller 41 is notch 3 of the eccentric disk 37.
When returning to the state 7a, there is a possibility that a stamping sound is particularly likely to be generated. However, in the sixth embodiment, the cushioning member 3 is used.
7b, 41b, the roller 41 is notched 37a.
The stamping sound at the time of returning to the normal state can also be effectively prevented.

The cushioning members 37b and 41b are formed of an elastic material such as rubber or resin, for example, but are not limited thereto, and may be other materials. In addition, the eccentric disk 37 and the roller 41, the cushioning member 37b,
41b is joined by press fitting, engagement, injection, or the like.

The buffer members 37b and 41b are provided in the sixth embodiment.
In the embodiment, it is mounted on both the eccentric disk 37 and the roller 41, but may be mounted on one of the eccentric disk 37 and the roller 41.

Further, as in the fifth embodiment, the radius (R1) of the notch portion 37a is changed to the radius (R1) of the roller 41.
2) It may be set larger (R1> R2).

The present invention is not limited to the above-described embodiment, but can be variously modified.

[0065]

As described above, according to the first aspect of the present invention,
According to the above, since the tip of the swing arm is pressed against the eccentric disk by the biasing means, the relationship between the eccentric disk and the swing arm is configured as a "swing follower" in cam terms. Can be. Therefore, when a reaction force is generated in the eccentric disk in the circumferential direction, even if a bending load acts on the swing arm, almost no friction force is generated as in the case of the conventional piston of the "linear follower". Therefore, the operation of the swing arm is not hindered.

Further, when the steering wheel is turned back, the eccentric disk is reversed, and the swinging direction of the swing arm is also inverted. Does not affect the reaction force generation of the eccentric disk, and it is not necessary to strictly manage the gap as in the related art.

According to the second aspect of the present invention, the radius (R1) of the notch portion is set to be larger than the radius (R2) of the roller (R1> R2), and the roller has one contact point at the notch portion. To make contact. Therefore, when the roller returns to the notch portion from the state in which the steering wheel is rotated left and right, the roller is moved to a position other than the notch portion by one.
The driver touches at one contact point, and even if it enters the notch part, it makes contact at one contact point, so no stamping noise is generated, and the driver feels discomfort due to the stamping sound. There is no such thing as giving.

Further, according to the third aspect of the present invention, since the buffer member is provided on both the outer peripheral surface of the eccentric disk and the outer peripheral surface of the roller, or one of the outer peripheral surfaces, the eccentric disk The contact between the metal and the roller is avoided to prevent the sound of stamping between the two, thereby preventing the driver from feeling uncomfortable. When the roller returns to the notch portion of the eccentric disk, there is a possibility that the stamping sound is particularly likely to occur. However, according to the third aspect, the roller returns to the notch portion by the buffer member. The stamping sound at the time of performing can also be effectively prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram of a vehicle steering device according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a reaction force generator of the steering device shown in FIG. 1;

FIG. 3 is a partially cutaway bottom view of the reaction force generator of the steering device shown in FIG. 1 as viewed from below.

FIG. 4 is a sectional view taken along the line AA of FIG. 2;

FIG. 5A is a graph showing a relationship between a steering angle and a reaction torque of the reaction force generator according to the first embodiment;
(B) is a graph showing the relationship between the steering angle and the reaction torque of the reaction force generator according to the second embodiment.

FIG. 6 is a cross-sectional view of a reaction force generator of a vehicle steering system according to a second embodiment.

FIG. 7 is a longitudinal sectional view of a reaction force generator of a vehicle steering system according to a third embodiment of the present invention.

8 is a partially cutaway bottom view of the reaction force generator of the steering device shown in FIG. 7 as viewed from below.

FIG. 9 is a sectional view taken along the line AA of FIG. 7;

FIG. 10 is a sectional view taken along the line BB of FIG. 7;

FIG. 11A is a graph showing a relationship between a steering angle and a steering torque of a reaction force generator according to a third embodiment, and FIG. 11B is a graph showing a modification of the third embodiment. 4 is a graph showing a relationship between a steering angle and a steering torque of the reaction force generator.

FIG. 12 is a longitudinal sectional view of a reaction force generator of a vehicle steering system according to a fourth embodiment of the present invention.

FIG. 13 is a sectional view taken along the line AA of FIG. 12;

FIG. 14 is a sectional view taken along the line BB of FIG. 12;

FIG. 15A is an enlarged view of an eccentric disk and a roller, in which a radius (R1) of a notch portion of the eccentric disk is set smaller than a radius (R2) of the roller (R1 <R2). (B) shows a fifth embodiment of the present invention,
It is an enlarged view of an eccentric disk and a roller, and shows the case where the radius (R1) of the notch part of an eccentric disk is set larger (R1> R2) than the radius (R2) of a roller.

FIG. 16 is a sectional view of a vehicle steering apparatus according to a sixth embodiment of the present invention, and is a view corresponding to FIG. 10 of the third embodiment.

FIG. 17 is a schematic view of a conventional reaction force generator of a steering device.

[Explanation of symbols]

 Reference Signs List 10 steering controller 11 steering wheel 12 angle sensor 13 reaction force generator 14 electric motor 15 reduction gear 16 steering shaft 17 conversion mechanism 18 tie rod 19 wheel 20 position detection sensor 21 speed sensor 30 shaft 31 column 32 bearing 33 bearing 34 gear box 35 Small gear 36 Large gear 37 Eccentric disk (cam) 37a Notch portion 37b Buffer member 38 Rotation angle stopper projection 40 Swing arm 41 Roller 41b Buffer member 42 Adjustment bolt 43 Spacer 44 Compression spring 45 Roller G Swing center 50 Worm wheel 51 Worm 52 Reaction Force Motor 53 Clutch 56 Bearing 57 Bearing 58 Spacer 59 Adjust Bolt

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Sakae Matsumoto 1-8-1, Sojacho, Maebashi, Gunma Prefecture Inside Japan Seiko Co., Ltd. (72) Inventor Tetsuo Nomura 1-8-1, Sojacho, Maebashi, Gunma Prefecture Japan Seiko Co., Ltd. (72) Inventor Hiroshi Eda 78 Toba-cho, Maebashi-shi, Gunma F-term in NSK Ltd. CA13 CA17 CA18 CA31

Claims (3)

[Claims] 1. A steering direction and a steering angle of a steering wheel are detected, a detection signal is input to a controller, and a steering direction and a steering angle of a wheel are determined in consideration of a vehicle speed. A steering apparatus for a vehicle in which a wheel is steered by an electric motor, comprising: an eccentric disk that rotates in response to rotation of a shaft of a steering wheel; and a tip that abuts the eccentric disk. The swing arm provided freely, and the tip of the swing arm is pressed against the eccentric disk,
And a biasing means for biasing the swing arm. 2. The eccentric disk has a notch at a position where the amount of eccentricity is least, and the swing arm has a rotatable roller at a tip end thereof. 2) is set to be larger than the radius (R2) of the roller (R1> R2). 3. The swing arm has a rotatable roller at a tip end thereof, and a buffer is provided on both or one of an outer peripheral surface of the eccentric disk and an outer peripheral surface of the roller. The vehicle steering device according to claim 1, further comprising a member.