JPH07112608A - Suspension for vehicle - Google Patents

Abstract

PURPOSE:To generate sufficient damping force with good responsiveness without making an orifice or the like small, prevent a housing and a shaft from inflicting an excessive twisting action on each other, and use a rotary damper in common for various suspensions. CONSTITUTION:This suspension for a vehicle is provided with a suspension member 14 vertically moved by the bound and rebound of a wheel and a rotary damper 32 having a housing 34 and a shaft 36 relatively rotatably coupled around the rotary axis, generating damping force via the relative rotation of them, and fixed to the suspension member 14 by the shaft 36. One end of a lower link 38 is solidly connected to the housing 34, one end of an upper link 44 is pivotally fitted to a vehicle body at a position higher than one end of the lower link 38, and the other end of the upper link 44 is pivotally fitted to the other end of the lower link 38.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension for a vehicle such as an automobile, and more particularly to a suspension incorporating a rotary damper.

[0002]

2. Description of the Related Art A rotary damper generally has a housing and a shaft that are fitted relative to each other about a rotation axis so as to be rotatable relative to each other, and is configured to generate a damping force by the relative rotation of the housing and the shaft. As one of suspensions for vehicles such as automobiles in which the rotary damper is incorporated, as described in, for example, JP-A-2-283511, the rotary damper is suspended so that the rotation axis of the rotary damper and the pivot axis of the suspension arm coincide with each other. Incorporated into the pivotal part of the arm on the vehicle side,
2. Description of the Related Art A suspension configured to rotate a housing relative to a shaft by pivoting a suspension arm has been known in the related art.

According to such a suspension, when the suspension arm pivots about its axis by bouncing and rebounding of the wheel, the rotary damper causes the housing to rotate relative to the shaft about the axis of rotation. Since the damping force is generated, compared with the case where the cylinder-piston type shock absorber is disposed between the vehicle body and the suspension arm in a state of substantially vertically extending, It is possible to reduce the space between them and increase the vehicle interior space.

[0004]

However, in the suspension in which the rotary damper is incorporated as described above, the relative rotation angle of the housing and the shaft of the rotary damper is the same as the pivot angle of the suspension arm, and the wheel bounding is limited. The pivot angle of the suspension arm due to rebound is not so large, and correspondingly the moving flow rate of hydraulic oil inside the damper is small, so sufficient damping force cannot be generated with good responsiveness. In order to generate sufficient damping force with a small relative rotation angle, the orifice or choke clearance of the rotary damper must be reduced, and therefore the orifice or choke clearance must be processed and set with extremely high accuracy. There is a problem.

Further, since the damping force generated by the rotary damper largely depends on the length of the suspension arm that rotationally drives the housing relative to the shaft, a unique rotary damper is set for each suspension having a different suspension arm length. Therefore, there is a problem that a rotary damper having a certain damping force characteristic cannot be shared by various suspensions.

When an input is applied to the wheels in the vehicle front-rear direction or left-right direction from the road surface during acceleration / deceleration or turning of the vehicle, the force is transmitted to the housing of the rotary damper through the suspension arm, The rotary damper must have a strong structure to withstand the external force, because the shaft twists against the shaft, and the housing and the shaft do not rotate smoothly relative to each other. There is a problem that the damping force is easily disturbed.

Further, in the suspension as described above,
Since the rotary damper is installed with its rotation axis aligned with the axis of the suspension arm, if a rebound stopper is installed inside the rotary damper or in the vicinity of the rotary damper, the relationship between the suspension arm and rebound stopper arm ratio Therefore, there is a problem that the rebound stopper has to have a very high strength.

In view of the above problems in the conventional suspension in which the rotary damper is incorporated, the present invention can generate a sufficient damping force with good responsiveness without reducing the orifice or choke clearance of the rotary damper. (EN) Provided is an improved vehicle suspension in which a housing and a shaft do not exert an excessive prying action on each other and a rotary damper having a certain damping force characteristic can be commonly used in various suspensions. That is the primary purpose.

In addition to the above-mentioned features, the present invention also provides a vehicle in which the rotary damper also has a function as a conventional rebound stopper, which does not require an independent rebound stopper for restricting excessive rebound of the wheels. The second purpose is to provide a suspension.

[0010]

According to the present invention, the above-mentioned first object is to fit a suspension member that moves up and down in accordance with the bounding and rebounding of a wheel with each other so as to be rotatable relative to each other around a rotation axis. A rotary damper having a housing and a shaft configured to generate a damping force by relative rotation of the housing and the shaft and fixed to the suspension member by one of the housing and the shaft; A first link that extends and is rigidly connected to the other of the housing and the shaft at one end, and a position that extends in a direction transverse to the rotation axis and is higher than the one end of the first link at one end. By a vehicle suspension having a second link pivotally attached to the vehicle body at the other end and pivotally attached to the other end of the first link at the other end. It is made.

According to the present invention, the second object mentioned above is such that, in the above-mentioned suspension, the angle formed by the first and second links approaches 180 ° as the wheel approaches the full rebound position. This is achieved by a vehicle suspension characterized in that it is configured.

[0012]

According to the former configuration described above, the rotary damper is fixed to the suspension member by one of the housing and the shaft, and the other of the housing and the shaft extends in the direction transverse to the rotation axis and at one end of the housing and the shaft. A first link rigidly connected to the other side of the shaft, and a first link extending in a direction transverse to the rotation axis and pivotally attached to the vehicle body at a position higher than one end of the first link at one end and a first link at the other end. Since it is connected to the vehicle body through the second link pivotally attached to the other end of the one link, when the suspension member moves upward, the first link causes the second link to move the rotation axis of the rotary damper. As the suspension member moves downwards, the first link is pivoted upwards about the rotary damper axis of rotation by the second link and thus the suspension. The housing and shaft even when the pension member moves upward and any downward direction is rotated in opposite directions about the rotational axis, thereby the rotary damper generates the damping force.

In this case, by appropriately setting the lengths of the first and second links and the position of one end of the second link,
It is possible to increase the ratio of the relative rotation angle of the housing and the shaft to the vertical displacement amount of the suspension member at the time of bouncing and rebounding of the wheel, and especially in the suspension having the suspension arm, the lengths of the first and second links. Is set to be shorter than the length of the suspension arm, the rotary damper is incorporated in the vehicle body side pivot portion of the suspension arm so that its rotation axis and the suspension arm pivot axis match.
The ratio of the relative rotation angle of the housing and the shaft to the pivot angle of the suspension arm is compared to that of a suspension configured to rotate one of the housing and the shaft relative to the other by the pivot of the suspension arm. Therefore, it is possible to generate a sufficient damping force with good responsiveness without reducing the orifice or choke clearance of the rotary damper.

Further, neither the housing nor the shaft of the rotary damper is directly fixed to the vehicle body, one of the housing and the shaft is fixed to the suspension member, and the other of the housing and the shaft is pivotally attached to each other. Since it is connected to the vehicle body by the second link, even if an input is applied to the wheels from the road surface in the vehicle front-rear direction or the left-right direction and the force is transmitted to the suspension member, the suspension member relative to the vehicle body front-rear direction or the left-right direction. Relative displacement is absorbed by the first and second links and their pivot joints, so that the housing and shaft are not overwhelmed by one another.

Further, by appropriately setting and changing the lengths of the first and second links and the position of one end of the second link, the housing and the housing with respect to the vertical moving speed of the suspension member due to the bouncing and rebound of the wheel It is possible to set and change the ratio of relative rotational angular velocities of the shaft relatively freely, and by this, it is possible to arbitrarily set and convert the damping force characteristics of the rotary damper with respect to wheel bound and rebound. It is possible to share a rotary damper having a certain damping force characteristic in various suspensions.

According to the latter configuration described above (the configuration described in claim 4), the angle formed by the first and second links is configured to approach 180 ° as the wheel approaches the full rebound position. As the wheels approach the full rebound position, the toggle action increases the relative rotation angle of the housing and shaft of the rotary damper, increasing the force required to rotate them relative to each other, effectively controlling the movement of the wheels in the rebound direction. Therefore, even if an independent rebound stopper is not provided, it is possible to reliably prevent the wheels from rebounding more than a predetermined amount when the vehicle travels.

According to the above-mentioned structure of the present invention, the length adjusting mechanism for adjusting the length of the first or second link or the position for attaching the second link to the vehicle body is adjusted. Mounting position adjusting means is provided. Therefore, it is possible to easily change the lengths of the first and second links and the position of one end of the second link, and thus it is possible to easily change the damping force characteristics of the rotary damper with respect to the wheel bound and rebound. Is.

According to the above-mentioned structure of the third aspect of the present invention, the distance between the rotation axis of the rotary damper and the instantaneous center of the first link is such that the wheel is substantially in the neutral position. Therefore, the distance gradually decreases as the bounce amount and the rebound amount of the wheel increase, so that the housing and the shaft with respect to the vertical movement speed of the suspension member accompanying the bounce and the rebound of the wheel are increased. The ratio of the relative rotational angular velocities and the damping force generated by the rotary damper gradually increase as the bounce amount and the rebound amount of the wheel increase, and the pair of left and right rotary dampers also cooperate with each other to function as a roll damper. Therefore, it is possible to effectively prevent excessive bounces and rebounds of the wheels and excessive rolls of the vehicle body while ensuring good riding comfort of the vehicle, thereby ensuring good steering stability of the vehicle.

[0019]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view showing an embodiment of a vehicle suspension according to the present invention configured as a rear end twist beam type rear suspension, and FIGS. 2 and 3 are enlarged views of the rotary damper shown in FIG. 1, respectively. FIG. 4 is an enlarged partial cross-sectional view showing a connecting portion between the lower link and the upper link.

In these drawings, reference numeral 10 denotes a carrier that supports a wheel (not shown) so as to be rotatable about an axle axis extending in the lateral direction of the vehicle, and 12 denotes a longitudinal direction of the vehicle. Reference numeral 14 denotes a trailing arm that extends and is laterally spaced from each other, and 14 denotes a twist beam that extends in the vehicle lateral direction. Trailing arm 12
Has a joint 16 including a rubber bush at its front end, and is connected to a vehicle body (not shown) so as to be pivotable about a pivot line 18 extending in the vehicle lateral direction by the joint 16. The rear end of the trailing arm 12 is integrally connected to the end of the twist beam 14 by welding or the like, and the inner end of the carrier 10 is also integrally connected to the end of the twist beam.

The twist beam 14 has a U-shaped cross-section that opens downward, and a stabilizer 20 that extends in the lateral direction of the vehicle is disposed inside the twist beam 14. Behind the twist beam 14, a lateral rod 22 is arranged which extends slightly in the vertical direction and extends in the lateral direction of the vehicle. The lateral rod 22 is pivotally attached to one carrier 10 at one end and is pivotally attached to the vehicle body at the other end, whereby the lateral rigidity of the suspension is ensured.

A lower spring seat member 24 is fixed to the upper surface of the end portion of the twist beam 14 by welding or the like. The spring seat member and an upper spring seat member not shown in the figure are fixed to the vehicle body. A compression coil spring 26 that functions as a suspension spring is mounted in between. A pair of brackets 28 are fixed to the spring seat member 24 behind the springs 26 by bolts 29.

The rotation axis 3 is provided between the pair of brackets 28.
A rotary damper 32 extending along 0 is arranged. The structure of the rotary damper 32 itself does not form the gist of the present invention, so a detailed description thereof will be omitted. The rotary damper is, for example, as described in Japanese Patent Laid-Open No. 56-28008, a rotary axis 30. It has any structure as long as it has a housing 34 and a shaft 36 that are fitted to each other so as to be rotatable relative to each other, and that the housing and the shaft rotate relative to each other to generate a damping force. You may

In the illustrated embodiment, the rotary damper 3
The second rotation axis 30 extends in the lateral direction of the vehicle, and the shaft 36 is serration-fitted with the bracket 28 and is fixed to the twist beam 14 via the bracket and the lower spring seat member 24. The lower end of a lower link 38 as a first link extending perpendicularly to the rotation axis 30 is rigidly connected to the housing 34 by welding or the like.
The lower link 38 extends in the vehicle front-rear direction by inclining downward when viewed from the upper end to the lower end.
The upper end of the joint 40 contains a resin bush inside.
Is pivotally attached to the lower end of an upper link 44 as a second link so as to be relatively pivotable about an axis 42 extending in the vehicle lateral direction.

The upper link 44 extends in the vehicle front-rear direction by inclining upward when viewed from the lower end toward the upper end.
The upper end of the upper link 44 is pivoted about an axis extending in the lateral direction of the vehicle at a position higher than the rotary damper 32 by a joint 46 including a rubber bush inside, and via a bracket not shown in the drawing. Is connected to the car body.

The effective length of the lower link 38, that is, the distance between the rotation axis 30 and the axis 42 of the joint 40 is more than the effective length of the trailing arm 12, that is, the distance between the pivot axis 18 and the rotation axis 30. Is also set small. Similarly, the effective length of the upper link 44, that is, the distance between the axis 42 of the joint 40 and the axis of the joint 46 is set smaller than the effective length of the trailing arm 12.

The instantaneous center of the lower link 38, that is, FIG.
And, as shown in FIG. 8, when the intersection point of the straight line 48 connecting the axis 18 and the rotation axis 30 and the axis 50 of the upper link 44 is O, the lengths of the lower link 38 and the upper link 44 and the upper ends of the upper links 44 are determined. The position is such that the distance L between the rotation axis 30 and the instantaneous center O is the largest when the wheel is not shown in the substantially neutral position, and the distance L gradually decreases as the wheel bounces and rebounds. Is set.

Further, as shown in FIG. 5, when the angle formed by the axis 52 of the lower link 38 and the axis 50 of the upper link 44 is α, the lower link 38 and the upper link 4 are shown.
The length of 4 and the position of the upper end of the upper link gradually increase the angle α as the rebound amount of the wheel not shown in the figure increases, and when the wheel is in the full rebound position, the angle α is slightly smaller than 180 °. It is set to be an angle.

In the illustrated embodiment, when the trailing arm 12 pivots about its axis 18 counterclockwise as viewed in FIG. 5 due to wheel bounce, the lower link 38 causes the trailing arm 38 to move. Relative to the rotary damper 32, the upper link 44 pivots in a clockwise direction about the axis of rotation 30 of the rotary damper 32, and the upper link 44 pivots in a counterclockwise direction about the axis of the joint 46, and thus the housing 34 of the rotary damper 32. The shaft 36 and the shaft 36 are rotated about the rotation axis 30 relative to each other, and the rotary damper generates a damping force on the compression side (wheel bouncing direction).

Conversely, when the trailing arm 12 pivots about its axis 18 in the clockwise direction as seen in FIG. 5 due to wheel rebound, the lower link 38 causes the rotary damper 38 to rotate relative to the trailing arm. 32 pivots in a counterclockwise direction about the axis of rotation 30 of 32 and the upper link 44 pivots in a clockwise direction about the axis of the joint 46, and thus again in this case the housing 34 and shaft 36 of the rotary damper 32. Are rotated about the rotation axis 30 relative to each other, and the rotary damper generates a damping force on the extension side (wheel rebound direction).

As shown in FIG. 5, the pivoting angles of the trailing arm 12 in the bounding direction and the rebounding direction are θtb and θtr, respectively, when the trailing arm is in the neutral position and when it is pivoted in the bounding direction. , Θb, θn, and θr, which are angles formed by the straight line 48 and the axis of the lower link 38 when the trailing arm is pivoted in the bounding and rebounding directions, respectively. When the relative rotation angles of the housing 34 and the shaft 36 of the damper 32 are θrb and θrr, respectively, the angles θrb and θrr are expressed by the following equations 1 and 2, respectively.

[0033]

[Equation 1] θrb = θb − θn

[Equation 2] θrr = θn−θr

As shown in FIG. 6, when the wheel is in the neutral position so that the position of the trailing arm 12 when the wheel is in the neutral position corresponds to the position of the trailing arm when the wheel is bound. When the positions of the upper link 44, the rotary damper 32, and the lower link 38 are moved, the angle formed by the axes of the lower links 38 before and after the movement is the relative rotation angle θrb of the housing 34 and the shaft 36 when the wheels bounce. Yes, this angle is larger than the pivot angle θtb of the trailing arm 12 in the bounding direction.

Similarly, as shown in FIG. 7, the wheels are in the neutral position so that the position of the trailing arm 12 when the wheels are in the neutral position corresponds to the position of the trailing arms when the wheels are rebound. In this case, when the positions of the upper link 44, the rotary damper 32, and the lower link 38 are moved, the angle formed by the axes of the lower links 38 before and after the movement causes the relative rotation angle of the housing 34 and the shaft 36 when the wheel rebounds. θrr, which is larger than the pivoting angle θtr of the trailing arm 12 in the rebound direction.

Therefore, according to the illustrated embodiment, the movement amount of the hydraulic oil in the rotary damper can be increased as compared with the case where the rotary damper is incorporated in the pivotal support portion at the front end of the trailing arm. A sufficient damping force can be generated with good response without reducing the orifice or choke clearance of the rotary damper, and the structure of the pivotal support at the front end of the trailing arm is the same as that of the conventional twist beam rear suspension. Since it may be provided, it is possible to surely prevent the structure of the pivotal support at the front end of the trailing arm from becoming complicated.

According to the illustrated embodiment, the distance L is the largest when the wheel is substantially in the neutral position, and becomes gradually smaller as the wheel bounces and rebounds.
Considering that the trailing arm 12 pivots about the axis 18 at the same angular velocity, the rotary damper 32
The relative rotational angular velocity between the housing 34 and the shaft 36 of the shaft gradually increases as the wheel bounces or rebounds from the neutral position. Therefore, the damping force generated by the rotary damper gradually increases as the amount of bounce and rebound of the wheel increases. As a result, it is possible to effectively prevent excessive bounces and rebounds of the wheels while ensuring a good riding comfort of the vehicle, and to secure a good steering stability of the vehicle.

According to the illustrated embodiment, the housing 34 and the shaft 36 of the rotary damper 32 are not directly fixed to the vehicle body, but the shaft 36 is connected and fixed to the twist beam 14 by the bracket 28 and the lower spring seat member 24. , Housing 34 is lower link 3
8, joint 40, upper link 44, joint 4
It is connected to the vehicle body by 6. Therefore, an input is applied to the wheels in the vehicle front-rear direction or the left-right direction from the road surface, such as when the vehicle accelerates or decelerates or turns, and the trailing arm 12 is displaced around its front end in the vehicle front-rear direction or the left-right direction. Also, since the relative displacement of the twist beam with respect to the vehicle body is absorbed by the elastic deformation of the joints 40 and 46 and the links 38 and 44, it is possible to reliably prevent the housing 34 and the shaft 36 from exerting excessive prying action on each other. As a result, the rotary damper can be operated smoothly and the damping force can be satisfactorily generated.

Also according to the illustrated embodiment, the lower link 3
8 and the lengths of the upper links 44 and the positions of the upper ends of the upper links are appropriately set and changed to adjust the relative rotation angle of the housing 34 and the shaft 36 with respect to the pivoting angle of the trailing arm 12 associated with the bound and rebound of the wheel. The ratio can be set and changed relatively freely, whereby the damping force characteristic of the rotary damper with respect to the bound and rebound of the wheel can be arbitrarily set and changed.

For example, in FIG. 9, the length of the lower link 38 is shown in FIG.
FIG. 9 is a skeleton diagram similar to FIG. 8 showing the operation of the illustrated embodiment when set shorter than the case of FIG.

In this embodiment, the distance L becomes smaller than in the case of FIG. 8, and the relative pivot angle of the lower link 38 with respect to the pivot angle of the trailing arm 12 accompanying the pivot movement of the trailing arm 12 is shown. As the ratio becomes larger, the relative rotation angles θtb and θtr of the housing and the shaft of the rotary damper correspond to the relative rotation angle θ in FIG.
Therefore, the damping force generated by the rotary damper for the same pivoting angular velocity of the trailing arm is larger than tb and θtr. It is higher than the damping force in the case of.

As can be seen from a comparison between FIG. 9 and FIG. 8, if the length of the lower link 38 is set longer than that in FIG. 8, the damping force generated by the rotary damper is on the compression side and the extension side. In both cases, the damping force is lower than that in the case of FIG.

10 and 11 are the same as FIG. 8 showing the operation of the illustrated embodiment when the length of the upper link 44 is set longer and shorter than that in FIG. 8, respectively. It is a skeleton diagram of.

In the embodiment shown in FIG. 10, the distance L
Is smaller on the bound side of the wheel than in the case of FIG. 8, and the ratio of the relative pivot angle of the lower link 38 to the pivot angle of the trailing arm due to the upward pivot of the trailing arm 12 is increased. Therefore, for the same pivoting angular velocity of the trailing arm, the damping force generated by the rotary damper is higher on the contraction side than in the case of FIG.

Further, in the embodiment shown in FIG. 11, the distance L becomes larger than that in the case of FIG. 8, and the lower link 38 with respect to the pivoting angle of the trailing arm due to the pivoting of the trailing arm 12 is moved. The ratio of relative pivot angles becomes smaller,
Therefore, when the trailing arm has the same pivot angular velocity, the damping force generated by the rotary damper is lower than the damping force in the case of FIG. 8 on both the contraction side and the extension side.

FIG. 12 is a skeleton diagram similar to FIG. 8 showing the operation of the illustrated embodiment when the upper end position of the upper link 44 is moved rearward of the vehicle as compared with the case of FIG.

In this embodiment, the distance L is smaller than that in the case of FIG. 8, and the lower link 3 with respect to the pivoting angle of the trailing arm accompanying the pivoting of the trailing arm 12 is used.
8, the damping force generated by the rotary damper for the same pivoting angular velocity of the trailing arm is the same as the damping force in the case of FIG. Will be higher than.

FIG. 13 is an enlarged partial front view showing an example of a lower link 38 suitable for these embodiments, and FIG. 14 is a partial cross-sectional view showing a main part of the lower link shown in FIG. In FIGS. 13 and 14, the same parts as those shown in FIGS. 1 to 4 are designated by the same reference numerals as those shown in these drawings.

In this embodiment, the link 38 has an upper portion 38A having a socket 40A of a joint 40 at an upper end (left end in the drawing) and a lower end portion (rightward in the drawing) not shown in the drawing. ) In the housing 3 of the rotary damper 32
Turnbuckle 6 that connects the lower portion 38B fixed to 4 and the lower end portion of the upper portion 38A and the upper end portion of the lower portion 38B.
It has 0 and. The turnbuckle 60 has a connecting pipe 62 and a pair of detent devices 64 arranged at both ends thereof, and the connecting pipe 62 has a lower end portion of the upper portion 38A and a lower portion 38A.
B has internal threads on both ends for screwing with male threads provided on the upper end. Although not shown in the drawing, the upper link 44 also includes the lower link 3 shown in FIGS. 13 and 14.
It has the same structure as the No. 8.

Thus, according to the illustrated embodiment, the turnbuckle 60 can be adjusted to relatively freely set and change the lengths of the links 38 and 44 without removing or replacing them. The damping force characteristic of the rotary damper can be easily set and changed.

FIG. 15 is a side view showing an example of a mounting position adjusting structure of the upper end of the upper link 44 suitable for the embodiment shown in FIG. In FIG. 15, the same parts as those shown in FIGS. 1 to 4 are designated by the same reference numerals as those shown in these figures.

In this embodiment, a pair of brackets 70 for fixing the joint 46 at the upper end of the upper link 44 to the vehicle body 68 are fixed to the vehicle body 68 by bolts 72 at their base portions, and each bracket is Joint 4
6 has a plurality of holes 76 for receiving the bolts 74 inserted through the sleeve. The holes 76 are spaced from each other in the front-rear direction of the vehicle so that the upper end of the upper arm 44, that is, the position of the joint 46 in the vehicle front-rear direction can be adjusted by appropriately selecting the holes through which the bolts 74 are inserted. It has become.

Also according to the illustrated embodiment, the lower link 3
8 and the length of the upper link 44 and the position of the upper end of the upper link are set so that the angle α gradually approaches 180 ° as the wheel approaches the full rebound position. Therefore, the toggle action of the lower link and the upper link causes the wheel to become full. As the rebound position is approached, the ratio of the relative rotation angle of the housing 34 and the shaft 36 to the amount of rebound of the wheel increases, which increases the damping force generated by the rotary damper 32, and thus even without the rebound stopper. It is possible to reliably prevent the wheels from rebounding excessively while the vehicle is traveling.

When the wheel is driven downward by a statically acting force such as when the vehicle is jacked up, the force is carried by the lower link 38 and the upper link 44 as a tensile stress. Moreover, in such a case, the lower link and the upper link are 180 ° from each other.
In order to prevent the above pivoting, for example, FIGS.
A rebound limiter may be provided to restrict pivoting of the housing 34 and lower link 38 relative to the shaft 36 as shown in FIG. The rebound limiter shown in FIGS. 16 and 17 is a base portion 80A fixed to the pair of left and right brackets 28 by screws 82 at both ends, and is integrally formed with the base portion 80A, and an angle of substantially 90 ° with respect to the base portion. The stopper portion 80B is configured to be bent at the stopper portion 80B, and the stopper portion 80B prevents the lower link from pivoting by a predetermined amount or more by coming into contact with the vicinity of the lower end of the lower link 38.

Further, according to the embodiment shown in the drawings, the rotary damper 32 has its shaft 36 connected and fixed to the twist beam 14 by the bracket 28, and the housing 34 is connected to the vehicle body by the lower link 38 and the upper link 44. Since it is provided in a state of being separated from the twist beam 14, it is generated inside the rotary damper by the operation of the rotary damper as compared with the case where the rotary damper is incorporated in the pivotal support portion of the front end of the trailing arm. The heat can be efficiently dissipated, whereby the rotary damper can be efficiently cooled.

Although the present invention has been described in detail above with reference to specific embodiments, the present invention is not limited to such embodiments, and other various embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art that it is possible.

For example, in the illustrated embodiment, the lower link 3
8 and the upper link 44 are arranged so as to incline in the vertical direction and extend in the vehicle front-rear direction, so that they are provided in a substantially front open state. It may be provided.

In the illustrated embodiment, the rotary damper 32 has its shaft 36 connected and fixed to the twist beam 14 by the bracket 28 and the housing 34 connected to the vehicle body by the lower link 38 and the upper link 44. The housing of the damper 32 may be connected and fixed to the twist beam 14, and the shaft 36 may be connected to the vehicle body by the lower link 38 and the upper link 44.

In the illustrated embodiment, the rebound stopper is not provided, but the vehicle to which the suspension of the present invention is applied is such as an off-road vehicle in which the wheels are separated from the road surface when the vehicle is running. In the case of a vehicle that does the above, an auxiliary rebound stopper may be provided near the rotary damper. Even in that case, since the rotary damper also functions as a rebound stopper as described above, the rotary damper is installed in the vehicle body side pivot portion of the suspension arm so that its rotation axis and the suspension arm pivot axis coincide with each other. The auxiliary rebound stopper can be made simpler than the structure described above and the structure described in the above-mentioned Japanese Patent Application No. 5-39399 and the drawings.

Further, although the illustrated embodiment is a rear end twist beam type rear suspension, the suspension of the present invention is not limited to this type, and the present invention moves up and down as the wheel bounces and rebounds. As long as it has a suspension member, it may be applied to any other suspension such as a double wishbone suspension or a rigid axle suspension.

[0061]

As is apparent from the above description, according to the configuration described in claim 1 of the present invention, the lengths of the first and second links and the position of the one end of the second link are adjusted. By properly setting, the ratio of the relative rotation angle of the housing and the shaft to the vertical displacement amount of the suspension member at the time of bouncing and rebounding of the wheel can be increased, and especially in the suspension having the suspension arm, By setting the length of the second link shorter than the length of the suspension arm, the rotary damper is installed in the suspension arm on the vehicle body side so that the rotation axis of the suspension and the suspension arm are aligned. , One of the housing and the shaft is rotated relative to the other by the pivoting of the suspension arm. It is possible to increase the ratio of the relative rotation angle of the housing and the shaft to the pivot angle of the suspension arm as compared to the case of the configured suspension, so that it is sufficient to reduce the orifice or choke clearance of the rotary damper. The damping force can be generated with good responsiveness.

Further, neither the housing nor the shaft of the rotary damper is directly fixed to the vehicle body, one of the housing and the shaft is fixed to the suspension member, and the other of the housing and the shaft is pivotally attached to each other. Since it is connected to the vehicle body by the second link, even if an input is applied to the wheels from the road surface in the vehicle front-rear direction or the left-right direction and the force is transmitted to the suspension member, the suspension member relative to the vehicle body front-rear direction or the left-right direction. Relative displacement of the two is absorbed by the first and second links and their pivotal joints, thus preventing the housing and shaft from being overwhelmed against each other, thereby making the rotary damper more robust than necessary. It is possible to avoid such a structure that the housing and the shaft are It is possible to improve the durability of the rotary damper generates the proper damping force by relatively smoothly rotated relative to the other.

Further, by appropriately setting and changing the lengths of the first link and the second link and the position of one end of the second link, the housing with respect to the vertical movement speed of the suspension member due to the bouncing and rebounding of the wheel. The ratio of relative rotational angular velocities of the shaft and the shaft can be relatively freely set and changed, whereby the damping force characteristic of the rotary damper with respect to the bound and rebound of the wheel can be arbitrarily set and converted. A rotary damper having characteristics can be shared by various suspensions.

Furthermore, since the shaft or housing of the rotary damper is carried by the suspension member by being fixed to the suspension member, it is described in, for example, Japanese Patent Application No. 5-39399 and the drawings related to the applicant's application. As compared with the case where the rotary damper is incorporated in the pivotal support between the first link and the second link as described above, the inertial mass to be carried by these links is small,
Therefore, it is not necessary for the two links to be strong, nor is the connecting structure of their pivots strong.

In particular, according to the above-mentioned structure of the second aspect of the present invention, it is possible to easily change the lengths of the first and second links and the positions of the one ends of the second links. The damping force characteristic of the rotary damper with respect to the bound and rebound of the wheel can be easily changed, and according to the configuration described in claim 3 of the present invention, for example, the rotation axis of the rotary damper and the first link. The distance between the vehicle and the instantaneous center of the vehicle is minimized when the wheel is substantially in the neutral position, while ensuring good ride comfort of the vehicle and excessive bounce of the wheel. It is possible to effectively prevent the rebound and the excessive roll of the vehicle body and ensure good steering stability of the vehicle.

Further, according to the above-mentioned structure of the fourth aspect of the present invention, the angle formed by the first and second links is configured to approach 180 ° as the wheel approaches the full rebound position. As the wheel approaches the full rebound position, the toggle action increases the relative rotation angle of the housing and shaft of the rotary damper, increasing the force required to rotate them relative to each other, effectively restricting the movement of the wheel in the rebound direction. Therefore, it is possible to reliably prevent the wheels from rebounding more than a predetermined amount when the vehicle is running, and it is possible to omit the rebound stopper.

[Brief description of drawings]

FIG. 1 is a perspective view showing one embodiment of a vehicle suspension according to the present invention configured as a rear end twist beam type rear suspension.

2 is an enlarged plan view showing the rotary damper shown in FIG. 1. FIG.

FIG. 3 is an enlarged side view of the rotary damper shown in FIG.

FIG. 4 is an enlarged cross-sectional view showing a connecting portion between a lower link and an upper link.

5 is a side view showing the operation of the embodiment shown in FIGS. 1 to 3. FIG.

FIG. 6 is an explanatory diagram showing a relationship between a pivoting angle of a trailing arm and a relative rotation angle of a housing and a shaft of a rotary damper when a wheel is bound.

FIG. 7 is an explanatory diagram showing a relationship between a pivoting angle of a trailing arm and a relative rotation angle of a housing and a shaft of a rotary damper when a wheel rebounds.

8 is a skeleton diagram showing the operation of the embodiment shown in FIGS. 1 to 7. FIG.

9 is a skeleton diagram similar to FIG. 8 showing the operation of the illustrated embodiment when the length of the lower link is set shorter than that in FIG.

10 is a view showing the operation of the illustrated embodiment when the length of the upper link is set longer than that in FIG. 8;
It is a skeleton diagram similar to.

FIG. 11 is a view showing the operation of the illustrated embodiment when the length of the upper link is set shorter than that in FIG. 8;
It is a skeleton diagram similar to.

12 is a skeleton diagram similar to FIG. 8 showing the operation of the illustrated embodiment when the position of the upper end of the upper link is moved rearward of the vehicle as compared with the case of FIG.

FIG. 13 is an enlarged partial front view showing an example of a lower link configured so that its length can be adjusted.

FIG. 14 is a partial cross-sectional view showing the main parts of the lower link shown in FIG.

FIG. 15 is a side view showing an example of a mounting position adjusting structure for the upper end of the upper link.

FIG. 16 is a plan view showing a rebound limiter.

FIG. 17 is a side view showing a rebound limiter.

[Explanation of reference numerals] 10 ... Carrier 12 ... Trailing arm 14 ... Twist beam 32 ... Rotary damper 34 ... Housing 36 ... Shaft 38 ... Lower link (first link) 44 ... Upper link (second link)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuhiro Kashima 2548 Tsuchida, Kani City, Gifu Prefecture, Kayaba Industrial Co., Ltd.Institute of Automotive Technology (72) Inventor Junichi Arai, 2548, Tsuchida, Kani City, Gifu Prefecture, Kayaba Industrial Co., Ltd. In-house

Claims (4)

[Claims] 1. A suspension member that moves up and down as a wheel bounces and rebounds, and a housing and a shaft that are fitted relative to each other so as to be relatively rotatable about a rotation axis, and a damping force is generated by relative rotation of the housing and the shaft. A rotary damper that is configured to generate and is fixed to the suspension member by one of the housing and the shaft, and rigidly connected to the other of the housing and the shaft at one end that extends in a direction transverse to the rotation axis. And the first link that extends in the direction crossing the rotation axis and is pivotally attached to the vehicle body at a position higher than the one end of the first link at one end and the other end of the first link at the other end. A vehicle suspension having a second link pivotally attached to the other end. 2. The vehicle suspension according to claim 1, wherein a length adjusting mechanism for adjusting a length of the first or second link or a mounting for adjusting a mounting position of the second link with respect to the vehicle body. A vehicle suspension characterized by being provided with position adjusting means. 3. The vehicle suspension according to claim 1, wherein the distance between the rotation axis and the instantaneous center of the first link is the largest when the wheel is substantially in the neutral position. A vehicle suspension characterized in that: 4. The vehicle suspension according to claim 1, wherein an angle formed by the first and second links is configured to approach 180 ° as the wheel approaches a full rebound position. The suspension for the vehicle.