JP2961904B2 - Steering knuckle stopper device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering knuckle stopper device for restricting a maximum turning angle of a wheel.

[0002]

2. Description of the Related Art In a conventional steering knuckle stopper device, a wheel is steered to a maximum turning angle by disposing a knuckle stopper on a suspension arm and disposing a stopper bolt serving as a projection on the knuckle arm. In this case, the stopper bolt of the knuckle arm is brought into contact with the knuckle stopper to regulate the maximum turning angle of the wheel.

However, in the steering knuckle stopper device, when the wheel is steered at a high speed, when the stopper bolt comes into contact with the knuckle stopper, an impact sound is generated due to collision between the rigid bodies, and a reaction force against the collision is generated. May be transmitted to the steering wheel (handle) via the knuckle arm, which may cause discomfort to the driver. Furthermore, when the wheel collides with a curb or the like in a state where the wheel is steered to the maximum turning angle (a state where the stopper bolt is in contact with the knuckle stopper), the collision load is directly transmitted to the steering system or the suspension via the knuckle stopper or the stopper bolt. Since the input is made to components such as the suspension arm constituting the system, it is necessary to reinforce the components, which tends to increase the weight.

For this reason, in a conventional steering knuckle stopper device, as described in, for example, Japanese Utility Model Laid-Open Publication No. 59-129672, an axially movable bolt is provided at the tip end of a stopper bolt that comes into contact with the knuckle stopper. By mounting the cap via an elastically compressible shock-absorbing member, the impact noise caused by the collision between the knuckle stopper and the stopper bolt serving as the protrusion is reduced, and the collision load from the wheel is absorbed.

[0005]

However, in the conventional steering knuckle stopper device, at the time of the maximum turning angle of the wheel, the stopper bolt of the knuckle arm is brought into contact with the knuckle stopper provided on the suspension arm, and the wheel is stopped. By restricting the steering, the swing of the knuckle arm is restricted, and at best, it only has an effect of absorbing the impact sound and impact when the stopper bolt collides with the knuckle stopper, and at the time of the maximum turning angle of the wheel There is no action to positively improve the steering resilience.

Therefore, for a vehicle having a link structure in which the resilience of the steering deteriorates when the wheels are turned to the maximum, the caster is dynamically changed to improve the resilience by changing the trail amount. There is a problem that a complicated mechanism is required for the steering system, such as reduction of the steering angle.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and has been developed for a vehicle in which the resilience of the steering is deteriorated at the time of the maximum steering of the wheel. The purpose is to enhance sex with a simple mechanism.

[0008]

In order to achieve the above object, a steering knuckle stopper device according to the present invention contacts a knuckle stopper provided on a suspension arm with a projection provided on the knuckle arm. Let me
In a steering knuckle stopper device for restricting a maximum turning angle of a wheel, the knuckle stopper is provided with a leaf spring which is elastically deformed in a contact direction of the projection.

In addition, it is preferable that the projecting surface of the connecting portion connecting the end portion of the tie rod and the knuckle arm be a projecting portion without particularly forming the projecting portion with a bolt or the like.

[0010]

The wheel is steered as the knuckle arm rotates, and when the wheel is steered to the maximum turning angle, the projection provided on the knuckle arm is moved to the knuckle stopper provided on the suspension arm. In contact therewith, the maximum turning angle of the wheel is regulated.

[0011] At this time, the tip of the protruding portion contacts the leaf spring of the knuckle stopper, and the impact is absorbed by bending the leaf spring to reduce the impact noise.
Further, even when a collision load from a curb or the like is input to the wheel in a state where the protrusion is in contact with the knuckle stopper, the overlapping leaf spring bends and absorbs the input so that steering from the knuckle stopper or the stopper bolt is performed. The input of the collision load to a system or a suspension system is suppressed.

Subsequently, the knuckle arm is returned to a predetermined rotation angle by pushing back the projection abutting on the laminated leaf spring by the elastic restoring force of the flexed laminated leaf spring, thereby generating the steering wheel. The wheel is turned back to the slip angle corresponding to the cutting torque to be made.

When the projecting surface of the connecting portion connecting the end portion of the tie rod and the knuckle arm is regarded as a projection, it is not necessary to attach a bolt or the like to the knuckle arm particularly for disposing the projection.

[0014]

An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a steering knuckle stopper device on the inner wheel side. First, as shown in FIG. 1, a knuckle arm 2 is rotatably connected to an end of a tie rod 1 interlocking with a steering wheel (handle) (not shown). The side of the suspension arm 6 side of the connection between the tie rod 1 and the end of the tie rod 1 is regarded as a projection 3 to be brought into contact with a knuckle stopper 7 described later, and the other end of the knuckle arm 2 is integrally fixed to a knuckle spindle 4. A wheel 5 is coaxially and rotatably supported on the outer periphery of the knuckle spindle 4.

One end of a suspension arm 6 is swingably connected to a lower portion of the knuckle spindle 4 on the vehicle body side via a ball joint, and the other end of the suspension arm 6 is connected to a vehicle body (not shown). A knuckle stopper 7 is attached to the front surface of the knuckle stopper 2 at the side of the suspension arm 6 opposite to the projection 3 at the middle of the suspension arm 6. ing.

The knuckle stopper 7 is shown in FIGS.
As shown in FIG. 6, the spring 6a comprises a leaf spring 7a mounted on the front surface of the concave portion 6a. The leaf spring 7a is formed by stacking three spring plates, and has a long diameter in both ends at a longitudinal direction. A long hole 7c is provided. The bolt 7b is passed through the elongated hole 7c of the leaf spring 7a and bolted to the upper edge of the recess 6a, so that both ends of the leaf spring 7a can slide in the longitudinal direction. The leaf spring 7a can be bent in the groove direction of the recess 6a.

In the steering knuckle stopper device having the above-described structure, when a steering wheel (not shown) is rotated to turn the vehicle, the knuckle arm 2 is rotated via the tie rod 1 to steer the wheels 5. And the knuckle arm 2 increases as the turning angle of the wheel 5 increases.
Approaching the suspension arm 6 and subsequently turning the wheel 5 to the maximum turning angle, the projection 3 of the knuckle arm 2 comes into contact with the leaf spring 7a of the knuckle stopper 7 disposed on the suspension arm 6. In contact therewith, the maximum turning angle of the wheel 5 is regulated.

In this case, even if the wheel 5 is steered at a high speed, the leaf spring 7a bends in the groove direction of the concave portion 7b to absorb the collision of the projection 3, and the contact noise due to the collision is reduced. . Further, even if the wheel 5 is steered to the maximum turning angle and collides with a curb or the like, the collision load is absorbed by further bending of the overlapping leaf spring 7a, and the knuckle stopper 7 and the projection The input to the steering system and the suspension system of the impact load from the unit 3 is suppressed.

Subsequently, the bent leaf spring 7a pushes back the protrusion 3 by its elastic restoring force, and the wheel 5
Cut back the cut angle. Generally, the steering link structure is preferably closer to the Ackerman type when the vehicle turns at an extremely low vehicle speed where the centrifugal force can be ignored. However, when the vehicle turns at a certain speed or more, the wheel 5 ( A slip angle occurs in both the inner and outer wheels, and the turning angle of the wheel 5 increases by the slip angle. Further, axle steer is generated. When the helm is steered, there is room for the outer wheel turning angle. For this reason, the minimum turning radius is reduced,
In addition, for the purpose of reducing the steering force, the steering link structure may be made closer to a parallel type by further increasing the maximum turning angle of the outer wheel and lowering the Ackerman ratio.

However, if the Ackerman ratio is reduced to a predetermined value or more in order to reduce the steering force, the steering torque is deteriorated due to generation of a cutting torque (torque toward the turning center). It is particularly preferable to apply the steering knuckle stopper device of this embodiment to a vehicle having such a steering link structure.

The knuckle stopper 7 of this embodiment is designed to correct the deterioration of the steering resilience at the time of the maximum steering by the elastic restoring force of the overlapping leaf spring 7a. Back, the inner ring 5
The steering angle is increased by providing a slip angle corresponding to the cutting torque.

More specifically, in a steering link structure in which the Ackerman ratio decreases according to the actual inner wheel steering angle as shown in FIG. 4, for example, the steering force is reduced, but the resilience is deteriorated.

Assuming that the distance between the shafts is 2.65 m and the distance between the kingpins of the inner and outer rings is 1.505 m, and the cutting angle of the inner ring is α and the cutting angle of the outer ring is β, the Ackerman rate is 100%. The following expression (1) is satisfied. 1.505 (──── =) 0.5679 = COT β-COT α (1) 2.65 For example, if the maximum turning angle of the inner ring is 35 degrees, and the Ackermann rate is 100%, the cutting of the outer ring from (1) above The corner is 2
Although the angle is 6.6 degrees, the Ackerman ratio is 65% from the graph of FIG. 4, so the link structure of the steering becomes closer to the parallel type and becomes larger, and the actual turning angle of the outer wheel is about 2 degrees.
It becomes 9.5 degrees. Then, since the cutting angle of the inner ring on the Ackerman theory with respect to the cutting angle of the outer ring of 29.5 degrees is 39.8 degrees from the equation (1), the cutting angle of the inner ring is 35.
The inner ring is cut back by 4.8 degrees from the degree, and a cutting torque is generated in the inner ring. Further, as shown in FIG. 5, as the Ackerman rate decreases, the cutting torque around the kingpin also increases, and the increased cutting torque is input to the knuckle arm 2. The steering performance is improved by the generation of the two cutting torques, but the steering stability of the inner wheels is deteriorated.

In this embodiment, in order to correct the deterioration of the restoring property, the knuckle arm 2 is pushed back by the elastic restoring force of the leaf spring 7a, so that the slip angle of the inner ring 1 is reduced, and the cutting torque is controlled by the steering system. The turning angle of the inner wheel 1 is turned back so that the slip angle is just enough to balance the friction at the joint of the knuckle arm due to the overall ratio, etc., to correct the deterioration of the steering stability at the time of maximum turning. I have.

For example, if the angle to be turned back to correct the slip angle at which the friction and the cutting torque are balanced is 5 degrees, and the length of the knuckle arm 2 is 178 mm, the arm of the knuckle arm 2 To rotate the knuckle arm 2 at one end of the knuckle arm 2 and forming the projection 3 by 178 mm x Tan 5 degrees = 15 mm. You can return it with Accordingly, the leaf spring 7a
The elastic restoring force of the knuckle arm 2 is determined in accordance with the elastic restoring force of the knuckle arm 2 in accordance with the angle to be restored, and the repulsive force is determined to determine the spring constant and the expansion / contraction stroke length of the leaf spring 7a.

Here, since the overlapping leaf spring 7a is used to push back the projection 3 of the knuckle arm 2 which has collided with the knuckle stopper 7, it is simpler than a coil spring or other elastic body only by bolting. The knuckle arm 2 has good durability, and it is easy to select a stroke length of expansion and contraction and a spring constant for determining a distance for pushing back the projection 3 of the knuckle arm 2 and a repulsive force.

In this embodiment, the knuckle stopper 7 is used.
The projection 3 of the knuckle arm 2 contacting the knuckle arm 2 is provided at the connecting portion between the knuckle arm 2 and the tie rod 1. 3 may be used.

[0028]

As described above, the steering knuckle arm stopper device according to the present invention regulates the maximum turning angle of the wheel, and receives an impact sound or input when the projection of the knuckle arm collides with the knuckle stopper. It also has the effect of reducing the transmission of the impact that has occurred, and also has the function of turning back the turning angle of the wheel, so that even in the case of a steering link structure where the restorability of the steering deteriorates at the maximum turning angle, the notch generated in the steering There is an effect that the wheels can be switched back to the slip angle corresponding to the torque, thereby improving the steering resilience.

Further, by using a leaf spring as an elastic body for improving the resilience of the steering wheel, compared to other elastic bodies such as a coil spring, the spring can be easily mounted only by bolting and has a high durability. In addition, there is an effect that it is easy to select a stroke length of expansion and contraction and a spring constant for determining a distance for pushing back the protrusion 3 of the knuckle arm 2 and a repulsive force.

Further, since the projecting surface of the connecting portion connecting the end of the tie rod and the knuckle arm is regarded as a projection, there is also an effect that it is not necessary to attach a bolt or the like in particular to form the projection on the knuckle arm. is there.

[Brief description of the drawings]

FIG. 1 is a top view showing a steering knuckle stopper device of the present embodiment.

FIG. 2 is a view showing attachment of a leaf spring according to the embodiment.

FIG. 3 is a diagram showing a front view of a leaf spring;

FIG. 4 is a diagram showing the relationship between the turning angle of the inner ring and the Ackermann ratio in the present embodiment.

FIG. 5 is a diagram showing a relationship between a cutting torque around a kingpin and an Ackermann ratio.

[Explanation of symbols]

 2 Knuckle arm 3 Projection 5 Wheel 6 Suspension arm 7 Knuckle stopper

Claims (2)

(57) [Claims] 1. A steering knuckle stopper device for restricting a maximum turning angle of a wheel by bringing a projection provided on a knuckle arm into contact with a knuckle stopper provided on a suspension arm. A steering knuckle stopper device comprising: a leaf spring that is elastically deformed in a contact direction of the protrusion. 2. The steering knuckle stopper device according to claim 1, wherein the protrusion is a protruding surface of a connecting portion connecting the end of the tie rod and the knuckle arm.