JPH07257132A - Vehicle suspension device - Google Patents

Abstract

PURPOSE:To enhance the responsiveness to variation in a buffer clearance, and to cope with the variation by use of simple means or a small input type actuator. CONSTITUTION:A bumper rubber 11 is attached to the outer periphery of a piston rod 6 projected upward from the upper end face of an outer cylinder 5 of a shock absorber 4. The lower end part of the bumper rubber 11 has two lower surfaces on opposite sides of the axis S1 of the shock absorber, one 11a of the two lower surfaces being relatively higher than the other thereof so as to form a protrusion 11b. The upper end face of the outer cylinder 5 vertically facing the lower end face of the bumper rubber 11 is formed with a stepped part so as to make the buffer clearances thereof equal to each other, and a grand packing 12 is secured to the upper end face. Thereby, a recess mated with the protrusion 11b is formed in the grand packing 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension system for vehicles such as a strut type and a double wishbone type equipped with struts.

[0002]

2. Description of the Related Art As a conventional suspension system for vehicles equipped with struts, there is one disclosed in, for example, Japanese Utility Model Laid-Open No. 60-96105. In this, a shock absorber having a lower end fixed to a wheel support member that rotatably supports a wheel extends upward, and an upper end of a piston rod of the shock absorber is elastically supported on the vehicle body side. Further, between the gland packing provided on the upper surface of the outer cylinder of the shock absorber and the vehicle body, a bumper bar is coaxially fitted onto the piston rod of the shock absorber.
The lower end surface of the bumper bar is opposed to the gland packing with a predetermined amount of buffer clearance.
The entire facing surface of this bumper bar gland packing is
Each of them is located on a plane orthogonal to the shock absorber axis, and when they come into contact with each other in the vertical direction, they engage with each other so that the entire surfaces come into contact with each other.

When the wheel side is fully bound, the outer cylinder of the shock absorber is pushed up and the gland packing on the upper surface of the outer cylinder comes into contact with the bumper bar. As a result, the shock is alleviated and the maximum compression amount of the shock absorber is regulated. At this time, during steady running of the vehicle (during normal running), a stroke length of a predetermined length is secured for the shock absorber so as not to adversely affect riding comfort, and sudden start, sudden braking, sudden steering, etc. Therefore, when the posture of the vehicle changes, it is desirable to limit the stroke amount so as not to adversely affect the steerability.

In view of this, the above-mentioned Japanese Utility Model Application Laid-Open No. 60-9610.
In the vehicle suspension device described in Japanese Patent Publication No. 5, the bumper bar is attached to the piston rod so as to be movable in the extension and contraction direction of the shock absorber, and the bumper bar is moved along the shock absorber shaft to move in the vertical direction. A hydraulic actuator for adjusting the position is provided.

Then, for example, in order to prevent the rear portion of the vehicle body from sinking when the vehicle suddenly starts, the vehicle suspension device having the above-mentioned configuration is adopted on the rear wheel side to detect the sudden start when the accelerator pedal is depressed. Then, the actuator is operated to move the bumper bar downwards,
Displace the clearance so that it is smaller than the initial setting position. As a result, the maximum expansion and contraction amount of the shock absorber is restricted, and the sinking of the rear part of the vehicle body when the vehicle suddenly starts is suppressed.

[0006]

However, in the above-described vehicle suspension device, the acting direction of the actuator with respect to the bumper bar and the direction of the load input to the bumper bar via the gland packing (shock absorber axial direction) are the same. Since the direction is the direction, a force sufficient to withstand the load input to the bumper bar is required for the fluid pressure applied by the actuator, and a high output actuator is required.

Further, since the actuator uses fluid pressure as a driving force, when the bumper bar is moved in a direction to widen the buffer clearance, that is, in order to return the bumper bar upward, it depends on the negative pressure as its thrust force. However, there is a problem in response performance, which affects the ride comfort performance when the vehicle shifts from the starting state to the straight traveling state, for example.

The present invention has been made by paying attention to the above-mentioned problems, and is a means or a small input actuator which has a good responsiveness to changes in the buffer clearance and has a simple displacement of the buffer clearance. The purpose is to be able to respond.

[0009]

In order to achieve the above object, a vehicle suspension device according to a first aspect of the present invention is provided for each wheel, and a wheel side member that moves up and down together with the wheel. Is equipped with a shock absorber in which one lower end of a cylinder or a piston rod that slides vertically in the cylinder is connected, and the other upper end is connected to a vehicle body side member, and a bumper bar is arranged on the outer periphery of the piston rod. In the vehicle suspension device which is provided and the cylinder-side end surface of the bumper bar is vertically opposed to the gland packing fixed to the end surface of the cylinder with a predetermined buffer clearance, the bumper bar and the gland packing are provided. While changing the buffer clearance between the bumper bar and the gland packing according to the relative rotational displacement between It is characterized by comprising displacement means.

At this time, as described in claim 2, the shapes of the portions of the bumper bar and the gland packing that are opposed to each other in the vertical direction are such that they can engage with each other when they are brought into contact with each other from above and below. In addition, the opposing surfaces of the two are configured to have an uneven shape in a substantially vertical direction from a plane orthogonal to the shock absorber axis, thereby configuring the interval displacement means, and in the initial setting state, the bumper bar and the gland packing. The above-mentioned opposing surfaces are parallel to each other and are in a engageable position.

The invention described in claim 3 is
By providing a pair or a plurality of pairs of convex portions or concave portions facing in the vertical direction on the mutually opposing surfaces of the bumper bar and the gland packing, the opposing surfaces of the both are unevenly formed substantially vertically from the plane orthogonal to the shock absorber axis. It is characterized by having the shape. Alternatively, claim 4
In the invention described in (1), the shapes of the mutually facing surfaces of the bumper bar and the gland packing are inclined vertically from the direction orthogonal to the shock absorber axis, so that the opposing surfaces of the both are orthogonal to the shock absorber axis. It is characterized in that it has a shape that is substantially vertical from a plane.

Further, the invention described in claim 5 is
The bumper bar has a rotating body shape with the shock absorber axis as a central axis, and at least 1 relatively protrudes toward a part of the upper surface of the gland packing.
Two protrusions are provided, and in the initial setting state, the interval displacement means is provided by setting the vertical rigidity of the portion of the bumper bar that vertically opposes the protrusions to be relatively low. .

The invention described in claim 6 is
It is a vehicle suspension device provided for the steered wheels, and the bumper bar is fixed to the piston rod, and the position when the wheels are not steered is set to the initial setting position. Characterize. In addition, claim 7
The invention described in (1) is provided with a rotary displacement actuator that supports the bumper bar relative to the piston rod so as to be capable of relative rotational displacement around the shock absorber axis, and that rotationally displaces the bumper bar around the shock absorber axis. It is characterized by

The invention described in claim 8 is
Based on the turning detection means for detecting the turning state of the wheels and the turning state detection value from the turning detection means, the bumper bar is moved from the initial setting position via the turning displacement actuator when turning the wheels. And a controller for rotationally displacing a predetermined angle. In addition, claim 9
The invention described in (1), based on the braking detection means for detecting the braking state of the vehicle and the braking state detection value from the braking detection means, initializes the bumper bar through the rotational displacement actuator during braking of the vehicle. And a controller for rotationally displacing a predetermined angle from a set position.

According to a tenth aspect of the present invention, the acceleration detecting means for detecting the acceleration state of the vehicle, and the rotational displacement during acceleration of the vehicle are based on the acceleration state detection value from the acceleration detecting means. And a controller for rotatably displacing the bumper bar from the initial setting position by a predetermined angle via the actuator.

[0016]

By providing the spacing displacement means, the buffer clearance between the bumper bar and the gland packing can be changed by the rotational displacement between the bumper bar and the gland packing. Becomes As a result, the buffer clearance can be changed according to the running state of the vehicle.

At this time, since the buffer clearance is changed by the relative rotational displacement between the bumper bar and the gland packing, when the bumper bar comes into contact with the gland packing and the stroke of the shock absorber is restricted, the buffer clearance is changed. The direction of the load input to the bumper bar and the rotational displacement direction are orthogonal to each other.

As the distance displacing means, for example, the means described in claim 2 is adopted. With this configuration, when the bumper bar and the gland packing are opposed to each other at a position where they can engage with each other, the opposing surfaces of the two are the same in the vertical direction over the entire surface. When the shock absorber contracts in this state, the opposing surfaces of the two come into contact with each other almost at the same time.

When a relative rotational displacement of a predetermined angle occurs between the bumper bar and the gland packing from this state, the vertically opposing positions on the opposing surfaces of the two are relatively displaced.
At this time, since the opposing surfaces of the both do not form a flat surface, they are in mutually opposed engagement positions, and the opposing surfaces of both are not parallel to each other. That is, the vertical gap between the facing surfaces of the two becomes non-uniform, and a wider portion and a narrower portion than the initial gap before the relative rotational displacement are generated.

When the shock absorber contracts in this state, the two come into relative contact with each other, but only the narrow portion of the facing surface of both comes into contact, so the stroke amount of the shock absorber is restricted to be smaller than the initial value. . Then, the stroke length of the shock absorber is set to a large value in the initial setting state by performing the initialization so that the facing surfaces are parallel to each other, and the relative rotational displacement occurs between the bumper bar and the gland packing. The stroke length of the shock absorber is restricted to be small in the state where the shock absorber is in operation.

Further, in the present invention as set forth in claim 3, in the initial setting state, the position of the convex portion provided on one of the facing surfaces vertically opposes the position of the concave portion provided on the other side, so that they are mutually opposed. Opposite to the engageable position, the vertical gap between the two is uniform over the entire surface. When a relative rotational displacement occurs between the bumper bar and the gland packing from the above state, the convex portion provided on one of the facing surfaces does not vertically face the concave portion of the other pair, and thus the convex portion position The vertical gap between the two is set smaller than the initial setting value.

As a result, the stroke length of the shock absorber is set large in the initial setting state, and the stroke length of the shock absorber is small in the state where the relative rotational displacement occurs between the bumper bar and the gland packing. Regulated. The amount of decrease in the buffer clearance after the relative rotation from the buffer clearance of the initial setting value is determined by the size of the convex portion.

Further, in the present invention as set forth in claim 4, in the initial setting state, since the facing surfaces of the bumper bar and the gland packing are in a parallel state, they face each other at positions where they can be engaged with each other. The vertical gap is uniform over the entire surface. When relative rotational displacement occurs between the bumper bar and the gland packing from the above state, the phase in the tilt direction between the opposing surfaces is shifted by an amount corresponding to the rotational displacement amount. Therefore, the portion of the gland packing that faces the lowermost portion on the bumper bar side in the vertical direction is located on the uppermost end side along the direction inclining from the lowermost end portion on the gland packing side according to the rotational displacement amount. The facing position shifts toward.

For this reason, the buffer clearance is set to be small in accordance with the rotational displacement amount. Further, in the structure described in claim 5, the lower surface of the bumper bar is on a plane orthogonal to the shock absorber axis, and the gland packing is formed with a protruding portion. Therefore, the buffer clearance is determined by the gap between the upper end surface of the protruding portion of the gland packing and the lower surface of the bumper bar facing the upper end surface.

At this time, since the rigidity of the bumper bar differs depending on the location, even when the gland packing comes into contact with the bumper bar with a relatively same load, the projecting portion contacts the portion having low rigidity. The elastic deformation is larger when they come into contact with each other. That is, the buffer clearance changes by the amount of this elastic deformation. The invention described in claim 5 is in view of this, and in the initial setting position state, since the protruding portion vertically opposes the bumper bar of the portion having low rigidity, a large buffer clearance is set, and
When a relative rotational displacement occurs between the bumper bar and the gland packing from the initial setting state, the above-mentioned protruding portion vertically opposes the portion of the bumper bar having higher rigidity than in the initial setting state, and the buffer clearance is restricted to be small. It

Further, the invention described in claim 6 is
One of the above-mentioned vehicle suspension devices is adopted for the steered wheels, generally the front wheels, and the bumper bar is fixed to the piston rod. In this case, the bumper bar is in a state of being integrally supported by the piston rod. In the case of a steered wheel, both the wheel and the wheel support member are steered by steering the steering wheel, but since the outer cylinder side of the shock absorber is fixed to the wheel support member, the outer cylinder is Rotate around the shock absorber shaft by an angle corresponding to the steered angle. On the other hand, since the upper end of the piston rod is elastically supported on the vehicle body side, the rotational displacement is restricted without following the rotation of the outer cylinder.

Therefore, due to the turning of the wheels, a relative rotational displacement around the shock absorber shaft occurs between the outer cylinder and the piston rod. At this time, the bumper bar is in a state of being integrally supported by the piston rod,
As a result, rotational displacement occurs between the bumper bar and the gland packing provided on the upper surface of the outer cylinder, and the buffer clearance as described above is restricted to a small value.

At this time, in the invention described in claim 6, since the above-mentioned initial setting is carried out at a position where the wheels are not steered, a predetermined buffer clearance is secured when the vehicle goes straight. Further, when the wheels are steered and the vehicle turns, the buffer clearance is regulated to be small and the roll rigidity is increased. In addition, claim 7
The invention described in (1) is a vehicle suspension device that can be adopted regardless of the steered wheels or the drive wheels, and adopts any one of the above vehicle suspension devices, and uses a displacement actuator for dynamic displacement. By rotating the bumper bar, the buffer displacement can be changed between the bumper bar and the gland packing, and the buffer clearance can be changed as described above.

At this time, since the input direction from the rotational displacement actuator to the bumper bar and the direction of the load (shock absorber axial direction) input to the bumper bar via the gland packing are orthogonal to each other, The displacement actuator does not have to support the load at its output. Therefore, the rotational displacement actuator can be supported by a small output device capable of rotating the bumper bar.

Further, there is no difference in response between turning from the initial setting position and turning from the turning position to the initial setting position. At this time, for example, it may be configured as described in claim 8. In this case, when the occurrence of turning of the vehicle is detected by the turning detection means, the bumper bar is rotationally displaced from the initial setting position, and in the turning state of the vehicle, the buffer on the wheel side where the vehicle suspension device is set is set. The clearance is regulated to be small and the roll rigidity during turning becomes high.

Similarly, it may be arranged as described in claim 9. In this case, when the occurrence of braking of the vehicle is detected by the braking detection means, the bumper bar is rotationally displaced from the initial setting position, and when the vehicle is in the braking state, the buffer on the wheel side where the vehicle suspension system is set. The clearance is regulated to be small and the nose dive during braking is suppressed.

Similarly, it may be configured as described in claim 10. In this case, when the occurrence of acceleration of the vehicle is detected by the acceleration detecting means, the bumper bar is rotationally displaced from the initial setting position, and when the vehicle is in an accelerating state, the buffer on the wheel side where the suspension system for the vehicle is set. The clearance is regulated to be small, and the sinking of the rear part of the vehicle body during acceleration is suppressed.

[0033]

Embodiments of the present invention will be described with reference to the drawings.
The vehicle suspension system according to the first embodiment is adopted on the side of wheels that serve as steered wheels, and the wheel support member and the wheels can be steered by an existing type steering mechanism. First, the configuration will be described. As shown in FIG. 1, a wheel (not shown) is rotatably supported by a wheel supporting member 1 such as a knuckle that constitutes a wheel side member, and a suspension arm 2 is attached to a lower end portion of the wheel supporting member 1. The outer end is swingably supported. Its suspension arm 2
Extends inward in the vehicle width direction, and its outer end is connected to a suspension member 3 which is a vehicle body side member so as to be vertically swingable.

The lower end of the shock absorber 4 is connected to the upper portion of the wheel support member 1, and the shock absorber 4 extends upward. Further, as shown in FIG. 2, from the upper end surface of the outer cylinder 5 of the shock absorber 4,
A piston rod 6 which can be vertically stroked along the axis of the shock absorber 4 projects upward. The upper end portion of the piston rod 6 is elastically supported on the vehicle body side by being screwed to the strut upper mount bracket 17 on the vehicle body side via the strut upper insulator 7.

The bearing upper seat 8 is supported by the strut upper mount bracket 17, and the piston rod 6 is loosely inserted into the opening in the center of the bearing upper seat 8. The spring upper seat 10 is attached to the bearing upper seat 8 via the bearing 9, so that the spring upper seat 10 is supported on the vehicle body side in a rotatable state about the shock absorber axis S1.

A substantially cylindrical bumper bar 11 is press-fitted coaxially with the piston rod 6, and the bumper bar 11 is fitted between the spring upper seat and the upper end surface of the outer cylinder 5 to form the piston rod. 6 Fixed and supported on the outer circumference. The lower end of the bumper bar 11 is
Among the left and right portions sandwiching the shock absorber shaft S1, one lower surface 11a is stepped so as to be relatively higher in the vertical direction than the other lower surface to form a convex portion 11b.

Further, the shape of the upper end surface of the outer cylinder 5 which vertically opposes the lower end surface of the bumper bar 11 is also stepped so that the buffer clearance B1 between them is equal, and the ground on the upper surface thereof. The packing 12 is fixed. As a result, on the side of the gland packing 12,
A pair of concave portions is formed on the convex portion 11b. As a result, the lower surface of the bumper bar 11 and the upper surface of the gland packing 12 have mutually engageable shapes, and
On both sides, the entire surface does not form a plane orthogonal to the shock absorber axis S1 and the gap displacement means K is formed.

A spring lower seat 13 is fixed to the outer peripheral portion of the outer cylinder 5, and the spring lower seat 13 is fixed.
And the spring upper seat 10 between the coil spring 1 and the shock absorber 4 are arranged substantially coaxially.
4 are supported. In addition, 15 is a spring upper rubber sheet. As a result, the coil spring 14 and the spring upper seat 10 are set to be rotatable in accordance with the rotation of the outer cylinder 5 around the shock absorber axis S1, and it is unnecessary for the coil spring 14 when the outer cylinder 5 is rotated. It is possible to prevent a twist from being input.

The position of the bumper bar 11 with respect to the piston rod 6 is regulated and fixed at a predetermined set position by the above-mentioned press fitting, and there is, for example, a means shown in FIG. This is because the distance piece 16 having a hole having a D-shaped cross section as shown in FIG. 4 is adhered to the upper surface of the bumper bar 11, and the portion 6a of the piston rod 6 previously cut into the D-shaped cross section is bonded. The bumper bar 11 may be aligned by inserting it in the position so that the relative positional relationship between the gland packing 12 and the bumper bar 11 is in the initial setting state.

The state where the wheels are not steered is set as an initial setting state, and at the position of the initial setting state, the lower surface of the bumper bar 11 and the upper surface of the gland packing 12 are set at positions where they can be engaged with each other. . Further, with respect to the buffer clearance B1 which is the gap between the lower surface of the bumper bar 11 and the upper surface of the gland packing 12 at this time, a desired gap determined from the riding comfort performance in normal straight running is ensured. Keep it.

Further, a steering mechanism (not shown) is connected to the wheel support member 1, and the wheel support member 1 and the wheels are steered by steering a steering wheel (not shown). In the vehicle suspension system having the above-described configuration, the buffer clearance B1 between the lower surface of the bumper bar 11 and the gland packing 12 is set to a large initial value so that the buffer clearance B1 can be increased as described above when the vehicle is traveling straight ahead. Is set to a large value, which does not adversely affect riding comfort.

When the steering wheel is steered from this state, the wheel support member 1 is passed through the steering mechanism.
And the wheels steer to turn the vehicle. At this time, the outer cylinder 5 of the shock absorber 4 rotates around the shock absorber axis S1 due to the turning of the wheel support member 1, but the rotation of the piston rod 6 is restricted by the vehicle body via the straddle upper insulator 7. Therefore, almost no rotational displacement occurs.

As a result, the bumper bar 11 fixed to the piston rod 6 also does not rotate. Therefore, the gland packing 12 attached to the outer cylinder 5
A relative rotational displacement occurs between the bumper and the bumper rubber.
Therefore, the position of the facing surface between the upper surface of the gland packing 12 and the lower surface of the bumper rubber is changed, and as shown in FIG.
Part 12 of the gland packing 12 that protrudes upward
a and a downwardly protruding portion 1 of the bumper bar 11
1b and the upper and lower sides are opposed to each other.

For this reason, the buffer clearance B1 becomes small, and the stroke length of the shock absorber 4 is suppressed, so that the roll rigidity becomes high and the maneuverability during turning of the vehicle is improved. When the steering wheel is returned from this turning state to return to straight traveling, the outer cylinder 5 and the gland packing 12 are relatively moved in synchronization with the return to the initial state of the wheels.
Returns to the original position and the buffer clearance B1 increases.

In the above embodiment, the bumper bar 11 and the gland packing 12 are opposed to each other, although the bumper bar 11 and the gland packing 12 are formed in a stepped manner so as to form a pair of a convex portion and a concave portion sandwiching the shock absorber shaft S1. The convex portion or the concave portion provided on each of the pair is not limited to this. For example, as shown in FIG. 6, a pair of convex portions or concave portions may be provided at four positions (position 18 in FIG. 6) sandwiching the shock absorber shaft S1. In the case of the above-mentioned embodiment, in the state of relative rotation, only one part of the left and right positions of the shock absorber shaft S1 may make one-sided contact, which may cause friction or the like in the shock absorber 4, but as shown in FIG. By doing so, the bumper bar 11 and the gland packing 12 can come into contact with each other at a target position sandwiching the shock absorber shaft S1 even in the state of relative rotation. Further, in the case as shown in FIG. 6, the turning displacement amount is limited as compared with the above embodiment, but when considering the target turning speed, the steering angle at that time is usually 10 degrees or less. There is no problem because it is as small as

In the example shown in FIG. 6, four convex portions and concave portions are provided, but two pairs, three symmetrical pairs, or five or more pairs sandwiching the shock absorber shaft S1 are set. Good. Next, a second embodiment will be described. The configuration of the second embodiment is the same as that of the first embodiment, and the shapes of the upper surface of the gland packing 22 and the lower surface of the bumper bar 21 are only different from those of the first embodiment.

That is, as shown in FIG. 7, the bumper bar 2
By processing the lower surface of 1 and the upper surface of the gland packing 22 from a plane position orthogonal to the shock absorber 24 so as to form surfaces that are inclined at the same angle and in the same direction, each opposing surface becomes a shock absorber shaft. The space displacing means K is realized as a shape that is substantially vertically concave and convex from a plane orthogonal to each other.

Even in this case, when the vehicle is traveling straight ahead, a predetermined buffer clearance B2 as shown in FIG. 7 is provided to ensure a predetermined good ride comfort performance. Then, when the wheels are steered, as shown in FIG. 8, a relative rotational displacement occurs between the bumper bar 21 and the gland packing 22 by an amount corresponding to the steered angle, and the steered angle increases. Along with buffer clearance B
2 is gradually reduced.

Therefore, the force for restraining the roll is weak for a small turning, and the force for restraining the roll can be set large for a large turning, so that a progressive characteristic can be obtained. Next, a third embodiment will be described. As shown in FIG. 9, the basic configuration of the vehicle suspension system of the third embodiment is similar to that of the first embodiment except for the bumper bar 31.

The bumper bar 31 of the third embodiment has the same shape as that of the conventional rotary body around the shock absorber shaft S2, but its rigidity is left and right with the shock absorber shaft S2 sandwiched therebetween. The rigidity of one side 31a is set high and the rigidity of the other side 31b is set low. In FIG. 9, the rigidity of the shaded side is set low.

The shape of the gland packing 22 is such that one of the left and right sides 32a sandwiching the shock absorber 24 protrudes upward and is processed into a step to provide a relative convex portion 32a. Then, in a state where the wheels are not steered, the low rigidity portion 31b of the bumper bar 31 is arranged so that the upwardly projecting portion 32a of the gland packing 32 faces each other.

This constitutes the interval displacement means K. In the vehicle suspension device having such a configuration, the buffer clearance is determined by the vertical gap between the upper end surface of the portion 32a projecting upward of the gland packing 32 and the lower surface of the bumper bar 31, but the vehicle travels straight. At this time, since the bumper bar 31 portion facing the protruding portion 32a of the gland packing 32 is set to have low rigidity, even if the gland packing 32 relatively contacts the bumper bar 31, the bumper bar 31 is vertically moved. It becomes possible to elastically deform and to obtain the buffer clearance by the elastic deformation.

Further, when the wheels are steered, the gland packing 32 and the bumper bar 31 are relatively rotationally displaced around the shock absorber axis S2, and the projecting portion of the gland packing 32 is a highly rigid part of the bumper bar 31. Three
Facing 1a vertically. For this reason, even if the gland packing 32 relatively contacts the bumper bar 31, the elastic deformation of the bumper bar 31 becomes smaller than that when going straight, and the buffer clearance B2 is relatively small.

As a result, the same action and effect as those of the first embodiment are produced. Although only one protrusion 32a on the side of the gland packing 32 is provided in the above-described embodiment, as shown in FIG. 6 in the first embodiment, a plurality of protrusions are projected and the wheels roll. It is also possible to set the rigidity of the bumper bar 31 side portion that vertically opposes the plurality of convex portions in the initial setting state in which the steering wheel is not steered so as to be relatively low.

In the above embodiment, the shape of the gland packing 32 is stepped by projecting one side of the shock absorber shaft S2, but the shape of the gland packing 32 is not limited to this shape. Figure 1
As shown in 0, it may be set so as to be on a plane inclined by a predetermined angle from the plane orthogonal to the shock absorber axis S2.

Also in this case, the same operation as in the second embodiment
It can have an effect. Next, a fourth embodiment will be described. First, the structure will be described. As shown in FIG. 11, a shock absorber 40 having a lower end fixed to a wheel-side member such as a knuckle (not shown) extends upward.
From the upper end surface of the outer cylinder 41 of the shock absorber 40, a piston rod 42 that can be stroked in the shock absorber axis S3 direction is projected upward.

The upper end portion of the piston rod 42 is elastically supported on the vehicle body side by being screwed to the strut upper mount bracket 44 on the vehicle body side via the strut upper insulator 43. Further, the bearing upper seat 45 is fixed to the strut upper mount bracket 44, and the piston rod 42 is loosely inserted into the central portion of the bearing upper seat 45.

With respect to the bearing upper seat 45, the spring upper seat 4 is inserted through the bearing 46.
By attaching 7, the spring upper seat 47 is supported on the vehicle body side in a rotatable state about the shock absorber shaft S3. The piston rod 42
As shown in FIG. 12, a bottomed hole 42a having a predetermined length is provided coaxially downward from the upper end surface, and at a position near the bottom of the bottomed hole 42a, as shown in FIG. A pair of fan-shaped openings 42b are formed in the piston rod 42 so as to expand toward the outer circumference in the radial direction.

A rotary rod 48 is inserted into the bottomed hole 42a from above. A mounting hole penetrating in the radial direction is formed at the lower end of the rotary rod 48, and a support rod 49 is fitted into the mounting hole through the pair of fan-shaped openings 42b. As a result, when the rotary rod 48 axially rotates, the support rod 49 rotates about the shock absorber shaft S3, and the amount of rotation is regulated by the inner surface of the fan-shaped opening.

A bumper bar 51 is coaxially provided on the outer circumference of the piston rod 42. The bumper bar 51 is supported by the support rod 49, so that the axial rotation of the rotary rod 48 causes the bumper bar 51 to move. It is rotatable. A bearing or the like may be provided between the outer circumference of the piston rod 42 and the inner peripheral surface of the bumper bar 51 to reduce friction and the like during rotation.

The upper end of the rotary rod 48 is connected to the rotary displacement actuator 50, and the main body of the rotary displacement actuator 50 is fixed to the upper end of the piston rod 42. As a result, the rotational displacement actuator 50 exerts a reaction force on the piston rod 42 and the rotary rod 48.
Is configured to rotate. As the rotary displacement actuator, for example, an electric motor or a fluid pressure motor is used.

The lower end of the bumper bar 51 is
Of the left and right parts that sandwich the shock absorber shaft S3, one of the lower surfaces is processed into a stepped shape so as to project relatively more downward than the other lower surface, so that the relative convex portions 51a are formed.
Are configured. The shape of the upper end surface of the outer cylinder 41, which vertically opposes the lower end surface of the bumper bar 51, is also stepped so that the buffer clearance B3 between them is equal, and a gland packing 59 is provided on the upper surface thereof. Relative concave portion 5 that is fixed and forms a pair with the convex portion 51a.
9a is formed.

As a result, the lower surface of the bumper bar 51 and the upper surface of the gland packing 59 have mutually engageable shapes and are not positioned on the planes orthogonal to the shock absorber axis S3, so that the gap displacement means K is formed. Has been done. Further, the spring lower seat 53 is fixed to the outer peripheral portion of the outer cylinder 41, and the spring lower seat 5 is fixed.
A coil spring 54, which is disposed substantially coaxial with the shock absorber 40, is supported between the spring upper seat 47 and the spring upper seat 47. In addition, 55 is a spring upper rubber sheet.

Shock absorber 4 having the above structure
A vehicle suspension device including 0 is adopted as a vehicle suspension device that suspends four wheels on the left, right, front, and rear. Further, as shown in FIG. 14, the rotational displacement actuator 50 provided in the shock absorber 40 of each vehicle suspension device is connected to a controller 56, and each of the actuators 50 has a predetermined direction in accordance with a command value from the controller 56. It is designed to be driven to rotate.

Further, the controller 56 is equipped with a microcomputer and is connected to a steering angle sensor 57 which is a turning detection means attached to the steering wheel, and inputs a steering angle signal from the steering angle sensor 57. To do. Then, based on the detected value, it is possible to output a rotational drive command to each of the rotational displacement actuators 50a to 50d corresponding to the four wheels.

Here, the steering angle sensor 57 detects steering of the steering wheel and outputs a signal corresponding to the steering angle. In the vehicle suspension system having the above-described configuration, the buffer clearance B3 has an initially set size when the vehicle normally travels straight, and therefore, a predetermined ride comfort performance is secured by increasing the initial set value. To do.

Next, the operation of the vehicle when turning will be described with reference to FIG. When the steering wheel is steered to turn the vehicle in the straight traveling state, the steering is detected by the steering angle sensor 57 and a detection signal is supplied to the controller 56. The controller 56 inputs the above detection signal and determines whether the vehicle is turning (step 1). When it is determined that the vehicle is turning, the controller 56 issues a rotational drive command to all the rotational displacement actuators 50a to 50d. (Step 2), each rotating rod 48, support rod 4
A certain amount of each bumper bar 51 from the initial position via 9,
For example, it is rotationally displaced by 90 degrees.

Then, as shown in FIG. 15, since the projecting portion of the lower surface of the bumper bar 51 of each shock absorber 40 and the projecting side of the gland packing 59 face each other in the vertical direction, the buffer clearance B3 at the time of turning is small. By setting the roll rigidity, the rolling rigidity is increased, so that the turning stability of the vehicle is improved. Further, when the steering wheel is returned, the signal from the steering angle sensor 57 to the controller 56 is turned off. Then, the controller 56 determines that the vehicle is not turning, that is, returns to the normal straight traveling state, and supplies a return command to each of the rotational displacement actuators 50a to 50d (step 3). As a result, the bumper bar 51 is returned to the initial position via the rotary displacement actuators 50a to 50d, and the buffer clearance B3 is returned to a large value in the initial state, thereby ensuring a predetermined ride comfort performance.

In the fourth embodiment, the steering angle sensor 57 for detecting the actual steering of the steering wheel is adopted as the turning detection means, but the invention is not limited to this, and for example, the lateral G sensor. It is also possible to adopt 91 and detect the turning directly from the lateral acceleration applied to the vehicle body. In the fourth embodiment, the roll rigidity of all the four wheels is controlled to be high, but the roll rigidity of only the outer wheel on the turning side may be controlled to be high.

Further, in the above embodiment, the bumper bar 51
Although the pair of convex portions and the concave portions are formed by forming both the gland packing 59 and the gland packing 59 into a stepped shape, a plurality of pairs of convex portions and concave portions may be provided as shown in FIG. 6 in the first embodiment. Further, as shown in FIG. 16, both facing surfaces of the bumper bar 51 and the gland packing 59 may be formed obliquely.

In this case as well, the same action and effect as above can be obtained. However, in this case, since the buffer clearance can be selected in multiple stages according to the rotational displacement, the relationship between the rotational displacement amount and the buffer clearance amount is obtained in advance, and the relation is calculated based on the relationship. Then, the controller sets to output a rotational drive command of a rotational displacement amount according to the detected steering angle, and the control amount of the buffer clearance which changes by this changes the maximum contraction amount of each shock absorber. Therefore, the roll rigidity may be changed in multiple stages according to the posture of the vehicle body.

Next, a fifth embodiment will be described. The structure of the vehicle suspension device itself of the fifth embodiment is similar to that of the fourth embodiment. In the fifth embodiment, the fourth
The same members and devices as those in the embodiment are designated by the same numbers as those in the fourth embodiment. Shock absorber 4 having the above configuration
A vehicle suspension system including 0 is adopted as a vehicle suspension system for suspending left and right front wheels.

The rotary displacement actuator 50 provided on the shock absorber 40 of each vehicle suspension is connected to the controller 56, and the controller 56 is connected to the controller 56.
Each of them is driven to rotate in a predetermined direction in accordance with the command value from. Further, the controller 56 includes a microcomputer and is connected to a brake pedal sensor 58 which is a braking detecting means attached to the brake pedal, and inputs a braking signal from the brake pedal sensor 58. Then, based on the detected value, it is possible to output a rotational drive command to each of the rotational displacement actuators 50a to 50d corresponding to the two front wheels.

Here, the brake pedal sensor 58 detects the depression amount of the brake pedal and outputs a signal corresponding to the detected value. In the vehicle suspension system having the above-described configuration, the buffer clearance B3 has an initially set size when the vehicle normally travels straight, and therefore, a predetermined ride comfort performance is secured by increasing the initial set value. To do.

Next, the operation during braking of the vehicle will be described with reference to FIG. In the straight running state, when the brake pedal is depressed to bring the vehicle into the braking state or the braking state is changed, the vehicle tries to sink in front of the vehicle.
At this time, the amount of depression of the brake pedal is detected by the brake pedal sensor 58, and the detected value is supplied to the controller 56. The controller 56 inputs the above detection signal to determine whether or not braking is in progress (step 4). If braking is in progress, a rotational drive command is sent to the rotational displacement actuators 50a and 50b on the left and right front wheels (step 5). ), Each bumper bar 51 is rotationally displaced from the initial position by a predetermined amount via the respective rotation bar 48 and support bar 49.

Then, as shown in FIG. 15, the projecting portion on the lower surface of the bumper bar 51 of each shock absorber 40 and the projecting side of the gland packing 59 face each other in the vertical direction, so that the buffer clearance B3 during braking is small. It is set and pitching is suppressed. When the brake pedal is released again, the signal from the brake pedal sensor 58 to the controller 56 is turned off. Then, the controller 56 detects that the vehicle is not being braked, that is, the normal straight traveling state, and supplies a return command to the rotary displacement actuators 50a and 50b on the front wheels side (step 6), and the rotary displacement actuator 50 Return the bumper bar 51 to the initial position via the
The clearance B3 is set to a large value in the initial state to secure a predetermined ride comfort performance.

Although the brake pedal sensor 58 is used as the braking detecting means in the fifth embodiment, the invention is not limited to this, and the front and rear G sensor 92 is used to directly load the vehicle body. A change in the vehicle body posture, which is the braking state of the vehicle body, may be detected from the acceleration in the front-rear direction. Further, as shown in FIG. 16, both facing surfaces of the bumper bar 51 and the gland packing 59 may be formed obliquely.

Also in this case, the same action and effect as above can be obtained. However, in this case, since the buffer clearance can be selected in multiple stages according to the rotational displacement, the relationship between the rotational displacement amount and the buffer clearance amount is obtained in advance, and the relation is calculated based on the relationship. In addition, the controller is set to output a rotational drive command of a rotational displacement amount corresponding to the detected depression amount of the brake pedal, and the control amount of the buffer clearance which changes by this is set to the maximum contraction amount of each shock absorber. May be changed so that the number of steps may be changed in multiple stages according to the degree of depression to the front side of the vehicle body.

Next, a sixth embodiment will be described. The structure of the vehicle suspension device itself of the sixth embodiment is similar to that of the fourth embodiment. In the sixth embodiment, the fourth
The same members and devices as those in the embodiment are designated by the same numbers as those in the fourth embodiment. Shock absorber 4 having the above configuration
A vehicle suspension system including 0 is adopted as a vehicle suspension system that suspends left and right rear wheels.

Further, the rotational displacement actuator 50 provided on the shock absorber 40 of each vehicle suspension is connected to the controller 56, and the controller 56 is connected to the controller 56.
Each of them is driven to rotate in a predetermined direction in accordance with the command value from. The controller 56 is equipped with a microcomputer and is a throttle sensor 5 which is an acceleration detecting means attached to the throttle.
9 is connected to input an acceleration signal from the throttle sensor 59. Then, based on the detected values, the rotational displacement actuators 50a to
It is possible to output a rotation drive command to each of 50d.

Here, the throttle sensor 59 detects the opening degree of the throttle and outputs a signal corresponding to the opening amount. In the vehicle suspension system having the above-described configuration, the buffer clearance B3 has an initially set size when the vehicle normally travels straight, and therefore, a predetermined ride comfort performance is secured by increasing the initial set value. To do.

Next, the operation during acceleration of the vehicle will be described with reference to FIG. In the straight running state, when the accelerator pedal is depressed and the vehicle is accelerated or changes to the accelerated state, the vehicle rear side tends to sink. Then, the amount of depression of the accelerator pedal is detected by the throttle sensor 59 as the throttle opening, and the detected value is supplied to the controller 56. When the detection signal is input, the controller 56 determines whether the vehicle is accelerating (step 7). If the vehicle is accelerating, the controller 56 sends a rotational drive command to the rotational displacement actuators 50c and 50d on the left and right rear wheels. (Step 8) Each bumper bar 51 is rotated by a predetermined amount from the initial position via the respective rotary rods 48 and support rods 49.

Then, as shown in FIG. 15, since the projecting portion on the lower surface of the bumper bar 51 of each shock absorber 40 and the projecting side of the gland packing 59 face each other in the vertical direction, the buffer clearance B3 during acceleration is small. It is set to suppress pitching such as squats during acceleration. When the accelerator pedal is released again, the throttle sensor 59 for the controller 56 is returned.
The signal from turns off. Then, the controller 56
When the signal from the steering angle sensor 57 is off, that is, when the normal straight traveling state is detected, the return signal is supplied to the rotational displacement actuators 50 on the front wheels side (step 9). , The bumper bar 51 is returned to the initial position via the rotary displacement actuator 50,
The clearance B3 is set to a large value in the initial state to improve the riding comfort.

Although the throttle sensor 59 is used as the acceleration detecting means in the sixth embodiment, the invention is not limited to this, and the front-rear G sensor 92 is used to directly load the vehicle body. The change in the vehicle body posture, which is the acceleration state of the vehicle body, may be detected from the acceleration in the front-back direction. In the fourth to sixth embodiments, the turning displacement of the bumper bar 51 is detected by detecting any one of turning, braking, and acceleration occurring in the vehicle. All signals from the acceleration detecting means and the braking detecting means can be supplied, and when any one of turning, acceleration and braking is detected, the rotational drive command can be supplied to the corresponding rotary displacement actuator 50.

The rotation drive signal output from the controller 56 in response to the signals input from the sensors 57, 58, 59 is generated when each input signal is equal to or more than a predetermined threshold value, and a sudden start or The operation may be performed only when the vehicle attitude greatly changes due to sudden braking or the like.
Further, in the above-mentioned embodiment, although it is adopted for all four wheels, it may be adopted only for the front wheel side or only for the rear wheel side.

When braking, the bumper bar 5 on the front wheel side
Although only 1 is rotationally displaced, and only the bumper bar 51 on the rear wheel side is rotationally displaced at the time of acceleration, the bumper bar 5 corresponding to all four wheels even at the time of braking or acceleration.
It is also possible to set all of them to be rotationally displaced. Further, as shown in FIG. 16, both facing surfaces of the bumper bar 51 and the gland packing 59 may be formed obliquely.

Also in this case, the same action and effect as above can be obtained. However, in this case, since the buffer clearance can be selected in multiple stages according to the rotational displacement, the relationship between the rotational displacement amount and the buffer clearance amount is obtained in advance, and the relation is calculated based on the relationship. Further, the controller is set to output a rotational drive command of a rotational displacement amount according to the detected throttle opening amount, and the control amount of the buffer clearance which changes by this is the maximum contraction amount of each shock absorber. It may be changed, so that it may be changed in multiple stages according to the degree of depression toward the rear side of the vehicle body.

Next, a seventh embodiment will be described. 7th
As shown in FIG. 20, the vehicle suspension system according to the embodiment has a fourth structure.
It has the same structure as the vehicle suspension system of the embodiment, but only the bumper bar 70 is different. 7th
The bumper bar 70 of the embodiment is a shock absorber shaft S.
In the rotating body around 4, the left and right rigidity sandwiching the shock absorber shaft S4 is made different, and the rigidity of one side 70a is set low.

Then, in the initial setting state, the low rigidity portion of the bumper bar 70 is made to correspond to the upper and lower portions of the projecting portion of the gland packing 71. With this setting, when the gland packing 71 comes into contact with the bumper bar 70 at the initial setting position, the contact portion of the bumper bar 70 is largely elastically deformed, and the buffer clearance B4 can be obtained.

When the bumper bar 70 is rotationally displaced by the rotation of the rotational displacement actuator 72, the portion 70b of the bumper bar 70 which vertically opposes the projecting portion 71b of the gland packing 71 has higher rigidity than the initial setting position. Therefore, even if they come into contact with each other, the amount of elastic deformation is small, and the buffer clearance B4 is restricted to be small. The rotation control by the rotation displacement actuator 72 has the same structure as that of the fourth to sixth embodiments.

As described above, by operating each of the rotational displacement actuators 72, it is possible to obtain the same action and effect as those of the fourth embodiment. Although the gland packing 71 has a stepped shape in the above embodiment,
For example, as shown in FIG. 21, it may be formed in an obliquely inclined shape. Also in this case, the inclined gland packing 80
Above the high position of the inclined surface of the, the relatively soft portion 8 of the bumper bar 81 is initially set.
By facing 1a, the buffer
The clearance is earned, and the bumper bar 81 is turned from that state by a predetermined angle to regulate the actual buffer clearance small.

Further, in all of the above-mentioned embodiments, the coil suspension is adopted as the vehicle suspension device for the vehicle, but the present invention is not limited to this, and the suspension device for the vehicle uses the leaf spring as the spring member. May be.
The point is that the structure of the shock absorber may be as described above. Similarly, although the strut type vehicle suspension device is used in all of the above embodiments, a double wishbone type or multilink type vehicle suspension device provided with an upper link or the like may be used.

In all of the above embodiments, the lower end of the shock absorber is fixed to the wheel supporting member such as the knuckle, but it may be supported to the wheel side member such as the lower arm. Further, in all the above-mentioned embodiments, the outer cylinder part of the shock absorber is connected to the wheel side member and the piston rod tip part is connected to the vehicle body side. However, the shock absorber is inverted and the outer cylinder side of the shock absorber is connected to the vehicle body side. On the other hand, the present invention can be applied to a vehicle suspension device in which a tip end portion of a piston rod is connected to a wheel side member.

[0094]

As described above, the suspension system for a vehicle according to the present invention is configured as described in claim 1, so that the buffer suspension according to the running state of the vehicle can be obtained.
Clearance can be changed. The interval displacement means for changing the buffer clearance by the relative rotational displacement between the bumper bar and the gland packing sets the shape of the facing portion of both the bumper bar and the gland packing, as set forth in claim 2, for example. It can be realized.

As a concrete constitution of this shape, for example, the shape described in claim 3 or 4 may be adopted. At this time, in the vehicle suspension device described in claim 3, since the buffer clearance can be reduced by the height of the convex portion, the bumper bar and the bumper bar can be adjusted by adjusting the height of the convex portion. The buffer clearance at the time of relative rotational displacement with respect to the gland packing can be set to a desired small value.

Further, in the vehicle suspension device according to the fourth aspect, the buffer clearance can be continuously changed according to the relative rotational displacement amount of the bumper bar and the gland packing. Further, as described in claim 5, the distance displacing means has a bumper bar having a shape of a rotary body having a shock absorber axis as a central axis, and a part of an upper surface of the gland packing is relatively oriented toward the bumper bar. It is also possible to provide at least one projecting portion that projects upward, and in the initial setting state, the rigidity of the bumper bar that vertically opposes the projecting portion is set to be relatively low in the vertical direction.

When the steering wheel is used, a relative rotational displacement between the bumper bar and the gland packing is generated according to the turning of the wheel. Without changing the shape of the bumper bar and the gland packing, you can ensure sufficient buffer clearance when going straight and maintain ride comfort, while limiting the buffer clearance when turning to ensure roll rigidity. Therefore, the turning camber angle can be changed to the negative side to improve the turning stability.

Further, in the vehicle suspension device according to the seventh aspect, by adopting a rotary displacement actuator such as a small electric motor, it is not limited to the steered wheels.
It will be available for all of the wheels. At this time, the present invention has a structure in which the buffer clearance is changed by relatively rotationally displacing the bumper bar by the actuator for rotational displacement, so that the shock absorber contracts and the gland packing collides with the bumper bar,
The load input to the bumper bar is not required to be opposed by the output of the rotational displacement actuator as in the conventional case,
The output of the rotational displacement actuator may have a driving force enough to rotate the bumper bar around the shock absorber axis, and therefore a small actuator can be used.

Further, there is no difference between the operation in the direction to narrow the buffer clearance and the operation in the direction to widen it, and the responsiveness is good. For example, with the structure described in claim 8, the buffer clearance of the shock absorber at the start or during the turning of the vehicle can be restricted to a small value, and the turning stability is improved.

Further, according to the ninth aspect, the buffer clearance of the shock absorber at the time of braking the vehicle can be regulated to be small, so that the nose dive is suppressed and the maneuverability is improved. Further, according to the tenth aspect, the buffer clearance of the shock absorber at the time of acceleration of the vehicle can be regulated to be small, so that the depression of the rear portion of the vehicle body can be suppressed and the maneuverability is improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a vehicle suspension device according to a first embodiment of the present invention.

FIG. 2 is a side view showing a shock absorber in the vehicle suspension system according to the first embodiment of the present invention.

FIG. 3 is a diagram showing an example of a bumper bar positioning means in the vehicle suspension system of the first embodiment according to the present invention.

FIG. 4 is a sectional view taken along line CC of FIG.

FIG. 5 is a diagram showing a positional relationship between a bumper bar and a gland packing in the vehicle suspension system according to the first embodiment of the present invention when a relative rotational displacement occurs between them.

FIG. 6 is a plan view showing another example of the positional relationship between the convex portion or the concave portion forming a pair in the bumper bar and the gland packing in the vehicle suspension device according to the first embodiment of the present invention.

FIG. 7 is a side view showing a shock absorber in a vehicle suspension device according to a second embodiment of the present invention.

FIG. 8 is a diagram showing a positional relationship between a bumper bar and a gland packing when a relative rotational displacement occurs in the vehicle suspension system according to the second embodiment of the present invention.

FIG. 9 is a side view showing a shock absorber in a vehicle suspension device according to a third embodiment of the present invention.

FIG. 10 is a side view showing a shock absorber in a vehicle suspension device according to a third embodiment of the present invention.

FIG. 11 is a side view showing a shock absorber in a vehicle suspension device according to a fourth embodiment of the present invention.

FIG. 12 is a partially cutaway side view of a piston rod in a vehicle suspension device according to a fourth embodiment of the present invention.

13 is a cross-sectional view taken along the line AA in FIG.

FIG. 14 is a schematic system diagram of a vehicle suspension device according to a fourth embodiment of the present invention.

FIG. 15 is a diagram showing a positional relationship between a bumper bar and a gland packing when a relative rotational displacement occurs in a vehicle suspension system according to a fourth embodiment of the present invention.

FIG. 16 is a side view showing another example of a bumper bar and a gland packing in a vehicle suspension device according to a fourth embodiment of the present invention.

FIG. 17 is a diagram showing an example of the operation of the controller in the vehicle suspension system of the fourth example according to the present invention.

FIG. 18 is a diagram showing an example of an operation of a process at the time of braking of the controller in the vehicle suspension system of the fourth example according to the present invention.

FIG. 19 is a diagram showing an example of an operation of processing during acceleration of the controller in the vehicle suspension system of the fourth example according to the present invention.

FIG. 20 is a side view showing another example of a bumper bar and a gland packing in a vehicle suspension device according to a seventh embodiment of the present invention.

FIG. 21 is a side view showing a bumper bar and a gland packing in a vehicle suspension device according to a seventh embodiment of the present invention.

[Explanation of symbols]

 B1 to B3 Buffer clearance K Interval displacement means S1 to S3 Shock absorber shaft 1 Wheel support member (wheel side member) 4 Shock absorber 6 Piston rod 5 Outer cylinder 11 Bumper bar 11b Convex portion 12 Gland packing 12b Recessed portion 50 Rotational displacement actuator 56 Controller 57 Steering Angle Sensor (Turning Detection Means) 58 Brake Pedal Sensor (Braking Detection Means) 59 Throttle Sensor (Acceleration Detection Means) 50a-50d Shock Absorber

Claims (10)

[Claims] 1. A lower end portion of a cylinder or a piston rod that slides in the cylinder in the vertical direction is connected to a wheel-side member that is provided for each wheel and moves up and down together with the wheel, and the other upper end portion is connected to the wheel-side member. A bumper bar is provided on the outer circumference of the piston rod, and a cylinder side end surface of the bumper bar has a gland packing fixed to the end surface of the cylinder and a predetermined buffer clearance. In the vehicle suspension device which is open and is opposed in the up-down direction, an interval displacement means for changing the buffer clearance between the bumper bar and the gland packing according to the relative rotational displacement between the bumper bar and the gland packing is provided. A suspension system for a vehicle, which is characterized by being provided. 2. The bumper bar and the gland packing have a shape in which the portions facing each other in the up-down direction are shaped so that they can be engaged with each other when they are brought into contact with each other from above and below, and the facing surfaces of the two are respectively shocked. The interval displacing means is configured by forming a shape that is substantially vertical from a plane orthogonal to the absorber axis, and in the initial setting state, the facing surfaces of the bumper bar and the gland packing are parallel to each other. The vehicle suspension system according to claim 1, wherein the suspension system is in an engageable position. 3. The bumper bar and the gland packing are provided with a pair or a plurality of pairs of protrusions or recesses facing in the up-and-down direction on the mutually opposing surfaces, so that the opposing surfaces of the two are on a plane orthogonal to the shock absorber axis. 3. The vehicle suspension device according to claim 2, wherein the vehicle suspension device has a shape that is substantially vertically concave and convex. 4. The shape of the mutually opposing surfaces of the bumper bar and the gland packing is tilted vertically from the direction orthogonal to the shock absorber axis, so that the opposing surfaces of the both are respectively on a plane orthogonal to the shock absorber axis. The vehicle suspension device according to claim 2, wherein the suspension device has a shape that is substantially vertical. 5. The bumper bar has a shape of a rotating body with a shock absorber axis as a central axis, and at least one projecting portion relatively projecting toward the bumper bar is provided on a part of an upper surface of the gland packing, and the initial stage is provided. 2. The vehicle according to claim 1, wherein in the set state, the interval displacement means is provided by setting the vertical rigidity of the portion of the bumper bar that vertically opposes the protruding portion to be relatively low. Suspension system. 6. A vehicle suspension device provided for steered wheels, wherein a bumper bar is fixed to the piston rod, and the position of the wheel when not steered is set to the initial setting. The suspension system for a vehicle according to any one of claims 1 to 5, wherein the suspension system is located at a position. 7. A rotary displacement actuator for supporting the bumper bar so as to be rotatable relative to the piston rod about the shock absorber shaft, and for providing a rotary displacement actuator for rotating the bumper bar about the shock absorber shaft. The vehicle suspension system according to any one of claims 1 to 5. 8. A bump detecting means for detecting a turning state of a wheel, and a bumper bar via a turning displacement actuator when turning the wheel based on a turning state detection value from the turning detecting means. 8. The vehicle suspension device according to claim 7, further comprising: a controller that rotationally displaces a predetermined angle from the initial setting position. 9. A braking detecting means for detecting a braking state of a vehicle, and based on a braking state detection value from the braking detecting means, the bump para bar is moved from an initial setting position via an actuator for rotational displacement during braking of the vehicle. 9. The vehicle suspension device according to claim 7, further comprising: a controller that rotationally displaces a predetermined angle. 10. An acceleration detecting means for detecting an acceleration state of a vehicle, and based on an acceleration state detection value from the acceleration detecting means, a bumper bar from an initial setting position via an actuator for rotational displacement during acceleration of the vehicle. 10. The vehicle suspension device according to claim 7, further comprising: a controller that rotationally displaces a predetermined angle.