JPH08156547A - Front suspension - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a front suspension that suppresses vehicle pitching behavior by increasing anti-dive efficiency only during braking. A connecting position 10d (13a) at which a wind up link 13 and a lower link 10 are swingably connected passes through a wheel side connecting portion 10a of the lower link 10 and a vehicle body side connecting portion 10b on the vehicle body front side. The position is on the rear side of the vehicle body with respect to the one axis P ₂ . And windup link 1
Connection position 11 at which 3 and the upper link are swingably connected
c (13d) is provided on the second axis P ₃ that passes through the connection centers of both ends of the upper link 13. And
The connecting position 14d at which the lower end of the strut 14 and the wind-up link 13 are swingably connected is the second position described above.
It is provided at a position offset from the axis P ₃ to the front side of the vehicle body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automobile front suspension.

[0002]

2. Description of the Related Art A front suspension shown in FIG. 8 is known. In this front suspension, one end portions 3a and 4a of an upper link 3 and a lower link 4 are swingably connected to a wheel support member 2 that rotatably supports a wheel 1, and the base ends of the upper link 3 and the lower link 4 are connected. Parts 3b, 4b, 4c are members on the vehicle body side (not shown)
Is swingably connected to the upper link 3,
The lower end 5b is connected to the lower link 4 to provide the wind-up link 5, and the upper link 3 is also provided.
The lower end 5a of the strut 5 extending in the vehicle body vertical direction
It is a suspension that is connected.

[0003]

By the way, it is known that if the lower link of the front suspension is provided with an anti-dive angle, the pitching behavior of the vehicle is reduced during braking. Also in the front suspension shown in FIG. 8, when the lower link 4 is mounted, the front side of the vehicle body is lowered with respect to the road surface and the rear side of the vehicle body is raised with respect to the road surface, so that the vehicle is raised toward the rear side of the vehicle. It is possible to add an anti-dive angle that is inclined in the direction. However, on the front side of the vehicle body of the lower link 4,
It cannot be set low enough in relation to the minimum ground clearance.

If the lower link 4 is provided with a large anti-dive angle at the time of installation, a sufficient space must be secured above the vehicle body because the swing range of the upper link 3 is wide, but there is a restriction in the engine room or the like. It is difficult to secure a vehicle space. Further, the vertical input transmitted from the wheels to the vehicle body through the suspension is transmitted as a longitudinal input to the vehicle body due to the large anti-dive angle of the lower link 4, which deteriorates the riding comfort. There is a risk.

The present invention has been made in view of the above circumstances, and the anti-dive efficiency is increased only during braking to suppress the pitching behavior of the vehicle, and the flexibility of the vehicle body layout is widened so that the vehicle is comfortable to ride. The purpose is to provide a front suspension that does not deteriorate.

[0006]

According to a first aspect of the present invention, one end of the front suspension is swingably connected to an upper portion of a wheel supporting member that rotatably supports a wheel.
An upper link having the other end swingably connected to the vehicle body side member and one wheel side connection portion swingably connected to the lower portion of the wheel support member are arranged in a spaced manner in the vehicle body front-rear direction. A lower link having an A-shaped plan view in which two vehicle-body-side connecting portions are connected to a vehicle-body-side member so as to be rotatable about an axis in the vehicle front-rear direction and vertically swingable, and upper and lower end portions are respectively the upper links. And a wind suspension that is swingably connected to the lower link, and a front suspension that includes a vertically extending strut having a lower end swingably connected to a predetermined position of the wind up link. The connection position of the wind up link and the lower link is located on the rear side of the vehicle body with respect to the first axis passing through the wheel side connecting portion of the lower link and the vehicle body side connecting portion on the front side of the vehicle body. And location, the connection center of the windup link and the upper link, disposed on a second axis that passes through the coupling center at both ends of the upper link, the coupling position of the lower end and the windup link of said struts,
The front suspension is located at a position offset from the second axis toward the front side of the vehicle body.

The front suspension according to a second aspect is the same as the front suspension according to the first aspect.
The front suspension is characterized in that an elastic bush is interposed in each of the vehicle-body-side connecting portions and the bush rigidity of the elastic bush on the rear side of the vehicle is set lower than that of the elastic bush on the front side of the vehicle.

[0008]

According to the front suspension of the first aspect of the present invention, when the vehicle is braked, the connection of the windup link is offset to the front side of the vehicle body from the second axis passing through the connection center of both ends of the upper link. position,
Downward thrust is input from the struts. As a result, the rotational moment that is directed to the front side of the vehicle body about the connection point that intersects the second axis is transmitted to the windup link. By transmitting this rotational moment, the connecting position of the lower link, which is swingably connected to the lower end of the wind up link, is pushed upward. The connecting position of the lower link is a position on the rear side of the vehicle body with respect to the first axis passing through the vehicle body side connecting portion of the lower link and the vehicle body connecting portion on the front side of the vehicle body.
The anti-dive angle is given by arranging the vehicle so that it is inclined upward as it goes toward the rear of the vehicle. As a result, the anti-dive rate of the lower link is increased, and the pitching behavior of the vehicle during braking is suppressed.

Further, when the anti-dive angle is applied to the lower link, the upper link does not swing, so it is not necessary to secure a sufficient space above the vehicle body, and the degree of freedom in vehicle layout is widened. Furthermore, the anti-dive angle is attached to the lower link only during braking, so the vertical input transmitted from the wheels to the vehicle body via the suspension is not transmitted to the vehicle body as front-rear input, and the ride comfort is improved. Does not fall.

Further, according to the front suspension of the second aspect, of the two vehicle body side connecting portions connected to the vehicle body side member of the lower link, an elastic body having a low bush rigidity is provided at the vehicle body rear side connecting portion. Since the bush is installed, downward thrust is input from the struts, and the rotational moment transmitted to the wind up link pushes up the connecting position of the lower link that is connected to the wind up link at the same time. , The connection part on the rear side of the vehicle body is also pushed upward. As a result, the anti-dive rate of the lower arm is further increased, and the pitching behavior of the vehicle during braking is suppressed.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a front suspension arranged on the left side of a front wheel according to an embodiment of the present invention. A wheel support member 2 for rotatably supporting a wheel 1 includes an A type lower arm 10 and an I type upper arm. 11 and a tie rod 12 extend and are connected in the vehicle width direction, and a wind up link 13 extending in the up and down direction is connected between the A-type lower arm 10 and the I-type upper arm 11, and the wind up link is also provided. Strut 1 on 13
The lower ends of 4 are connected.

That is, the A-type lower arm 10 is provided apart from the connecting point 10a for swingably connecting to the wheel support member 2 and the vehicle body front-rear direction, and is connected to the vehicle body side member (not shown) of the vehicle and the axis P. Two connection points 10b and 10c that are rotatably rotated around _one and vertically swingable, and a connection point 1 that is rotatably connected to the lower end of the wind up link 13.
0d is a link member having a substantially A-shape in a plan view. The connecting point 10d at which the lower end of the wind-up link 13 connects is an axis line (first axis line) P connecting the connecting center of the connecting point 10a and the connecting center of the connecting point 10b on the front side of the vehicle body.
It is provided on the rear side of the vehicle body from ₂ .

The connecting point structure of this A type lower arm 10 is
The connection point 10a is rotatably connected to the lower end of the wheel support member 2 via a ball joint. The connecting point 10b, 10c, as shown in FIGS. 2 and 3, the elastic body bushing 10b _2, 10c ₂ are mounted inside connecting outer cylindrical portion 10b _1, 10c _1, respectively, the elastic body bushing 10b ₂ The inner cylinder members B ₁ and B ₂ of the vehicle body side member are mounted in the through holes 10c ₂ and 10c ₂ . here,
The elastic bush 10c ₂ attached to the connecting outer cylinder portion 10c on the rear side of the vehicle body has a structure having higher rigidity than the elastic bush 10b ₂ attached to the connecting outer cylinder portion 10b on the front side of the vehicle body. ing.

Further, the I-shaped upper arm 11 has a connecting point 11a which is rotatably connected to the wheel supporting member 2, a connecting point 11b which is swingably connected to a vehicle body side member, and a connecting center of these connecting points 11a and 11b. the connecting axis (second axis) P ₃
It is an I-shaped link member that is provided on the upper side and has a connecting point 11 c that swingably connects to the wind-up link 13.

The connecting structure of the I-shaped upper arm 11 is as follows.
The connection point 11a is rotatably connected to the upper end of the wheel support member 2 via a ball joint. The connecting point 11b, as shown in FIG. 4, coupling outside the cylindrical portion 11b ₁ elastic bushing 11b ₂ inside is mounted, the inner cylindrical member B ₃ of the vehicle body-side member into the insertion hole of the elastic body bushing 11b ₂ Is attached to the member on the vehicle body side so that it can swing vertically and horizontally. Here, the elastic bush 11b ₂
A bush having high rigidity is used in the same manner as the elastic bush 11b ₂ used at the connection point 10b of the A-type lower arm 10.

The wind up link 13 is shown in FIG.
Also, as shown in FIG. 5, a first wind-up link 13A that extends in the vertical direction and is connected to the A-type lower arm 10
And a second wind-up link 13B that is integrally connected at the upper end of the first wind-up link 13A and extends toward the vehicle front side and that is connected to the I-shaped upper arm 11 and the strut 14. The axes P ₄ and P ₅ of the first windup link 13A and the second windup link 13B intersect with each other near the coupling position.

Then, the first wind up link 13A
A connection point 13a formed at the lower end of the is connected to a connection point 10d of the A-type lower arm 10 via a ball joint in a swingable manner. In addition, the second wind-up link 13B connected to the I-shaped upper arm 11 includes the axis P _{4 of} the second wind-up link 13B and the I-shaped upper arm 1.
As shown in FIG. 5, the mounting hole 11d is formed in the I-shaped upper arm 11 at a position where the first axis P ₃ intersects.
In addition, a spherical body receiving member 11e having an inner peripheral surface formed in a spherical shape is mounted, and the spherical body portion 1 is provided on the outer periphery.
The outer cylinder member 13c integrally formed with 3b is externally inserted into the second wind-up link 13B, so that the spherical portion 13 is formed.
b is slidably supported on the inner peripheral surface of the spherical body receiving member 11e, and the connecting point 11c of the I-shaped upper arm 11 and the connecting point 13d of the second wind-up link 13B are swingably connected.

The strut 14 extending in the vertical direction of the vehicle body includes a coil spring 14a and a shock absorber 14.
The upper mount portion 1 at the upper end of the upper mount portion 1
4c is attached to a part of a vehicle body or a suspension member (not shown), and a lower end portion (connection point) 14d connected to the second wind up link 13B is
It is offset and connected to the front side of the vehicle body. That is, the connecting point 14d of the strut 14 is
With its the axis P ₆ is the axis P ₅ of the second windup link 13B intersect, as shown in FIG. 5, the second windup link 13B and type I upper arm 1
The elastic bush (elastic support member) 11d ₂ is mounted inside the connecting outer cylindrical portion 14d ₁ at a position separated from the connecting point 13d (11c) of No. 1 by a predetermined distance L, and the insertion hole of this elastic bush 14d ₂ is inserted. The second wind-up link 13B, into which the inner cylinder member 14d ₃ is externally inserted, is inserted into the second wind-up link 13B so as to be swingably connected to the second wind-up link 13B.

Further, as shown in FIG. 1, the tie rod 12 has an end portion 12a swingably connected to a lower side of a wheel supporting member via a ball joint so that a steering input in the vehicle width direction from the steering wheel is applied to the wheel. It is adapted to be transmitted to the support member 2. According to the front suspension configured as described above, as shown in FIG. 6, the first windup link 13A and the second windup link 13B that are integrally connected to each other have their axes P ₄ and P _{5 in} the vicinity of the connecting portion. Since the connecting point 13d (11c) of the I-shaped upper arm 11 and the second wind-up link 13B intersecting each other is provided on the axis P ₃ connecting the connecting points 11a and 11b at both ends of the I-shaped upper arm 11, I type upper arm 1
Even if the force F _W along the axis P ₄ is input from the wind-up link 13A to the I-type upper arm 11, the axis P
₃ times rotation moment is not generated.

Further, the strut 14 and the second wind-up link 13B intersect their axes P ₆ and P ₅ , and the connecting point 13d (11c) between the I-shaped upper arm 11 and the second wind-up link 13B is I. Since it is provided on the axis P ₃ connecting the connection points 11a and 11b at both ends of the type upper arm 11, the force F _s along the axis P ₆ from the strut 14 is applied to the I type upper arm 11 via the second wind up link 13B. Even if the input is input, no rotational moment about the axis P ₃ is generated in the I-shaped upper arm 11.

In this embodiment, the connecting point 14d of the strut 14 is separated from the connecting point 13d (11c) by a predetermined distance L.
Therefore, the torque M (T = F _s × L) obtained by multiplying the distance L by the downward force F _s of the strut 14 is applied to the wind up link 13 (first Bending torque is input to the wind-up link 13A and the entire second wind-up link 13B). When this bending torque is input, a bending reaction force that resists the bending torque is generated in the wind-up link 13. However, during normal running when no external input is applied, the bending reaction force and the torque M are in a balanced structure. ing.

Next, the behavior of the front suspension of this embodiment during vehicle braking will be described with reference to FIG. The solid line shows the arrangement of the front suspension during normal running. In this state, the anti-dive angle of the A type lower arm 10 is set to substantially zero. When the braking force F _B is applied to the vehicle 1, pitching occurs in the vehicle due to load movement in the vehicle front-rear direction due to deceleration. At this time, as shown in FIG.
The downward thrust F _sM (F _sM > F _s ) is input to the second wind up link 13 </ _b > B from. When this thrust F _sM is input, the wind up link 13 (the first wind up link 13A and the second wind up link 1
3B), the connection point 13 with the I-shaped upper arm 11
A counterclockwise rotation moment centered on d (11c) is transmitted. Due to this rotational moment, an upward force F _WM (F _WM > F _W ) is generated in the first wind up link 13A, and the upward movement of the first wind up link 13A causes a lower end portion of the first wind up link 13A. The vicinity of the connection point 10d of the A-type lower arm 10 that is connected to is pushed upward. Of the two connection points 10b and 10c that are connected to the vehicle body side member of the A-type lower arm 10 while pushing up near the connection point 10d,
Since the elastic bush 10c ₂ having a low bush rigidity is attached to the connection point 10c on the rear side of the vehicle body, the connection point 10c
c is also pushed up. As a result, as shown by the broken line in FIG. 7, the A-type lower arm 10 is arranged so as to be inclined upward toward the vehicle body direction side, and an anti-dive angle is provided.

Therefore, according to the front suspension of this embodiment, the connection point 13d of the second wind-up link 13B and the I-shaped upper arm 11 is applied during vehicle braking.
The second offset from (11c) to the front side of the vehicle body
The downward thrust F _sM (F _sM > F _s ) is input to the wind up link 13 B from the strut 14, so that the connection point 13 d (1
1c) as a center, a counterclockwise rotation moment is transmitted, and this rotation moment generates an upward force F _WM (F _WM > F _W ) on the first wind up link 13A, so that the first wind up link 13A is generated. In the vicinity of the connection point 10d of the A-type lower arm 10 that is connected to the lower end of the vehicle, the connection point 1 on the rear side of the vehicle body where the elastic bush 10c ₂ with low bush rigidity is mounted at the same time is pushed up.
Since 0c is also pushed up, A type lower arm 10
Is inclined upward as it goes to the rear side of the vehicle body and has an anti-dive angle. As a result, the anti-dive rate of the A-type lower arm 10 increases, so that the pitching behavior of the vehicle during braking can be suppressed.

Further, when the anti-dive angle is applied to the A type lower arm 10, the I type upper arm 11 does not swing, so that it is not necessary to secure a sufficient space above the vehicle body, and the degree of freedom of the vehicle layout is increased. Get wider Further, since the anti-dive angle is provided to the A-type lower arm 10 only during braking, the vertical input transmitted from the wheels to the vehicle body via the suspension is not transmitted to the vehicle body as a front-back direction input. The riding comfort does not decrease.

[0025]

As described above, the front suspension according to claim 1 of the present invention is arranged such that the lower link is inclined upward toward the rear side of the vehicle only when the vehicle is braked, and the anti-dive angle is increased. Since it is attached, the anti-dive rate of the lower link is increased, and the pitching behavior of the vehicle during braking can be suppressed.

Further, when the anti-dive angle is applied to the lower link, the upper link does not swing, so it is not necessary to secure a sufficient space above the vehicle body, and the flexibility of the vehicle layout can be widened. it can. Furthermore, since the anti-dive angle is attached to the lower link only when braking,
The vertical input transmitted from the wheels to the vehicle body via the suspension is not transmitted to the vehicle body as an input in the front-rear direction, and the riding comfort can always be improved.

Further, according to the front suspension of the second aspect, of the two vehicle body side connecting portions connected to the vehicle body side member of the lower link, an elastic body having a low bush rigidity is provided at the vehicle body rear side connecting portion. Since the bush is mounted, the connecting position of the lower link that is connected to the wind up link is pushed upward, and at the same time, the connecting portion on the rear side of the vehicle body is also pushed upward. As a result, the anti-dive rate of the lower arm is further increased, and the pitching behavior of the vehicle during braking can be suppressed.

[Brief description of drawings]

FIG. 1 is a perspective view showing a front suspension of the present invention.

FIG. 2 is a view showing a vehicle body side connecting portion on a vehicle body front side of a lower link according to the present invention.

FIG. 3 is a view showing a vehicle body side connecting portion on a vehicle body rear side of a lower link according to the present invention.

FIG. 4 is a diagram showing a vehicle-body-side connecting portion of an upper link according to the present invention.

FIG. 5 is a view showing a connecting structure of struts and upper links connected to the wind up link according to the present invention.

FIG. 6 is a schematic side view showing an input state from another link that acts on the coupling position of the wind up link and the upper link according to the present invention.

FIG. 7 is a schematic side view showing the behavior of the front suspension of the present invention during vehicle braking.

FIG. 8 is a perspective view showing a conventional front suspension.

[Explanation of symbols]

1 wheel 2 wheel support member 10 lower link 10a lower link wheel side connecting part 10b, 10c lower link vehicle body side connecting part 10d, 13a connecting position of wind up link and lower link 10b ₂ vehicle body side connecting part Elastic body bush 10c interposed ₂ Elastic body bush interposed in the vehicle body side connecting portion on the rear side of the vehicle body 11 Upper link 11a One end of upper link 11b Other end of upper link 11c, 13d Windup link and upper link Connection position 13A 1st wind up link (wind up link) 13B 2nd wind up link (wind up link) 14 Strut P ₁ Axis passing through the two vehicle body side connection parts of P ₁ lower link P ₂ Lower link wheel side connection The first axis P ₃ passing through the vehicle body part and the vehicle body side connecting part on the front side of the vehicle body. Second passing through the connecting center of both ends of the upper link
Axis

Claims (2)

[Claims] 1. An upper link having one end swingably connected to an upper portion of a wheel support member for rotatably supporting a wheel, and the other end swingably connected to a vehicle body side member.
One wheel-side connecting portion is swingably connected to the lower portion of the wheel supporting member, and two vehicle-body-side connecting portions that are spaced apart in the vehicle body front-rear direction are rotatable around the vehicle body front-rear axis about the vehicle-body member. And a lower link having an A-shape in plan view which is swingably connected, a wind up link whose upper and lower ends are swingably connected to the upper link and the lower link, and a lower end is wine. In a front suspension comprising a strut extending vertically with respect to a vehicle body, which is swingably connected to a predetermined position of a windup link, a connecting position of the windup link and the lower link is set to a wheel side connecting portion of the lower link. And a position on the rear side of the vehicle body with respect to the first axis passing through the vehicle body-side connecting portion on the front side of the vehicle body, and the connection center of the wind up link and the upper link is It is provided on a second axis passing through the connecting center of both ends of the upper link, and the connecting position of the lower end of the strut and the windup link is a position offset to the vehicle body front side from the second axis. The characteristic front suspension. 2. An elastic body bush is provided at each of the two vehicle body side connecting portions of the lower link, and the bush rigidity of the elastic body bush on the rear side of the vehicle body is set to be lower than that of the elastic body bush on the front side of the vehicle body. The front suspension according to claim 1, wherein the front suspension is provided.