JPS6067206A - Rear suspension of automobile - Google Patents

Abstract

PURPOSE:To reduce in weight and improve lateral rigidity and further realize control change of both camber and toe by providing three lateral links in such a manner as a projection point of a grounding point for a rear wheel is positioned between two straight lines. CONSTITUTION:A rear wheel 12 is rotatably supported by means of a wheel support 16, to which the tip 11b of a swing arm 11 is fixed, while a base end 11a is fitted to a car body so as to position the arm 11 in the longitudinal direction of the car body. Outer ends 13a, 14a, 15a of three, that is, the first- third lateral links 13, 14, 15, arranged in lateral direction of the car body, are fitted to the support 16, while inner ends 13b, 14b, 15b of said lateral links are fitted to the car body. By appropriately setting the length of each link, change of toe at the times of bumping and rebounding can be controlled.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a rear suspension that supports the rear wheel of an automobile so that it can rotate freely and also alleviates vibrations and shocks transmitted from the rear wheel. (Prior art) There are several types of automobile rear suspensions, one of which is the trailing arm type rear suspension.

What is the lateral load applied to the tires in the trailing arm suspension system? Since it is supported by the trailing arm, it is necessary to increase the total lateral rigidity of the trailing arm. Therefore, it is necessary to increase the arm span and strengthen the arm to avoid making the arm itself heavier. I can't do it. If the weight of the arm increases, it will lead to an increase in vehicle weight, which in turn will lead to deterioration of fuel efficiency and increase in manufacturing costs.In order to completely improve these problems, for example,
As disclosed in No. 2205, a suspension structure was proposed in which a lightweight swing arm placed in the longitudinal direction of the vehicle body was supported by two lateral links to increase lateral rigidity with an 11-diameter diameter. has been done. Figures 1 to 3 show the entire suspension system with this groove structure.

Figure 1 is a perspective view seen diagonally from the rear, with one end 18 on the front side.
The other end 1b of the swing arm 1, which is rotatably attached to the vehicle body (not shown), has outer ends of two lateral links 3 and 4 located below the vehicle body and extending in the width direction. 3a
.

4a is rotatably attached to the inner ends 31) of this asono z and lower lateral links 3, 4.

4b is rotatably mounted on the vehicle body.

The other end 1b of the swing arm 1 supports the eel 2 rotatably; - It also plays the role of a partner. The other end 1b of the swing arm 1 is connected to the vehicle body with a damper absorber (not shown) and a spring (not shown), which reduces vibration and shock from the wheel 2. Other end】b
can move up and down relative to the vehicle body. Figure 2 is a plan view of the entire suspension as seen from above.
The upper part of the figure is the front of the vehicle. FIG. 3 is a front view of the The Suspension gold car body viewed from the rear, where the up-down direction in the figure is the up-down direction of the car body, and the left-right direction is the width direction of the car body.

In the suspension 7 configured in this way, the inner ends 1b of the upper lateral link 3 and the lower lateral link 4,
The advantage of attaching 4b to the vehicle body is that the capper angle can be easily adjusted by adjusting the entire position. However, when the wheel 2 moves up and down with respect to the vehicle body, that is, during bump and rebound, the center O of the wheel 2 is supported by the upper and lower lateral links 3 and 4 and is approximately on an arc as shown by the broken lines of arrows A and B. Draw a trajectory. Therefore, the wheel center O moves up and down with respect to the car body, and also moves inside the car body (in the width direction of the car body, in the direction where the lateral link is provided to the wheel, i.e., the right side for the right wheel, and the right side for the left wheel). ).
That is, it moves in the direction of arrow C. When the wheel center O moves inward to the vehicle body, the other end 1b of the swing arm l on which the wheel note 2 is supported also moves inward to the vehicle body, and therefore the swing arm 1 rotates counterclockwise in FIG. 2 with one end iat as the center. will be passed on to Therefore, the other end of this swing arm l], b is supported. The IM wheel 2 is also turned counterclockwise (in the direction of the arrow). In other words, face the direction of toe out.

In this way, the above-mentioned suspension using 51 swing arms and two lateral links has the advantages of high lateral rigidity, light weight, and easy camber control. Moreover, the amount of change in toe of the tire during rebound cannot be controlled, and the wheel changes to the toe-out side during knockdown and rebound while driving, resulting in unstable running of the vehicle.

Furthermore, in general, in an independent suspension, it is effective to create a negative camber when bumping to improve the running stability of the vehicle. For this purpose, as shown in FIG. 3, the inner end 3b of the upper lateral link 3 is
All you have to do is move it downwards as shown. Note that lowering the inner end 3b completely downward is also desirable from the viewpoint of increasing the interior of the vehicle body, improving the comfort of living, and expanding the trunk space. However, if the inner end 3b'jz is lowered too much, there is a problem that too much negative camber is created when bumping, leading to uneven tire wear. Furthermore, if the entire inner end 3b is lowered as it is, it will approach the inner end 4b of the lower lateral link 4, and the pitch of all the lateral forces acting on the tire will become smaller, increasing the load on each link, reducing reliability and noise. The problem of growth arises.

(Object of the invention) In view of the above-mentioned problems, the present invention has been developed to
It has high stability and can control both camber change and toe change, as well as adjust the camber change during bumps and rebound.
The entire purpose is to provide the following information.

(Structure of the Invention) The rear suspension of the present invention rotatably supports the rear wheel with a wheel support, and the entire swing arm is positioned in the longitudinal direction of the vehicle body, and the entire base end of the swing arm is attached to the entire wheel support at the tip of the swing arm. It is attached to the vehicle body so that the tip can swing freely in the vertical direction of the vehicle body centering on the base end, and is configured to receive the rotational force from the rear wheel and the front and rear, and is connected to three points separated from each other on the wheel support. In an automobile rear suspension system, in which three lateral links are arranged in the width direction of the entire vehicle body, the outer ends of the three lateral links have inner end metals that are connected to three points spaced apart from each other on the vehicle body. The point is that the outer end connecting points of two of these lateral links are located in the longitudinal direction of the vehicle body, and the outer end connecting points of the remaining lateral links are located above the outer end connecting points of the two lateral links. The inner end connection points of the remaining lateral links located above are located below and forward of the vehicle body than the outer end connection points of the lateral links. Furthermore, the automobile suspension pen/min of the present invention has two lateral links passing through the outer end connecting points of the remaining lateral links and the outer end connecting points of the two lateral links, respectively. a straight line,
It is characterized by three lateral links arranged so that when projected onto a vertical projection plane extending in the longitudinal direction of the vehicle body, the projected point of the rear wheel's ground contact point is located between these two straight lines. (Example) Hereinafter, all examples of J's ability will be explained with reference to the drawings.

4 to 6 show a preferred embodiment of the present invention, and FIG. 4 is a perspective view as seen diagonally from the rear;
FIG. 5 is a plan view of the vehicle body viewed from three sides, and FIG. 6 is a side view of the vehicle body viewed from the rear. As shown in these figures, the rear wheel 12 is rotatably supported by a wheel support 16. The tip Jib of the swing arm 11 is fixed to this wheel support 16, and the base end 11a is fixed so that the swing arm ]■ is located in the longitudinal direction of the vehicle body.
is attached to the vehicle body. Furthermore, ノ+'i ji'i
The advantage of Ai] 1a is that the swing arm [l] can swing in the vertical direction of the vehicle body with the base end 11a'i as the center. For this reason, the wheel support 16 and rear wheel 12 are able to move in the downward direction of the vehicle body, but the lower end is attached to the wheel support 16 and the rear wheel 12 can move upward. The coil spring 17a and the damper unit 17b attached to the vehicle body properly limit the vertical movement of the vehicle body, and attenuate vibrations and shocks transmitted from the wheels. [Wheel support] 6 has three first wheels arranged in the lateral direction of the vehicle body. 2nd and 3rd lateral links], 3 + 14 + 15
outer end 13a.

14a and 15a were published by Rubber Bunno/Yu, Holge Joint, etc., and these three lateral links 13,
14, 15 inner end 13b.

14b and 15b are attached to the vehicle body. At this time,
The second radial link 14 is arranged such that the inner end 14b of the second lateral link 14 located above is located in front of the vehicle body by a distance +1, I II, and below the vehicle body by a distance +l dn with respect to the outer end],4a. are arranged. By doing so, it is possible to expand the entire interior of the vehicle body and expand the space inside the vehicle to improve comfort, or to fill the entire floor of the trunk room. Furthermore, since the inner end 14b is not only lowered completely downward but also moved forward, the second and third lateral recesses are mainly caused by the full lateral force], 4.
], the inner end 14b of 5.

The pitch between the links 15b does not become small, and the load on each link can be prevented from increasing.

Note that both ends of the swing arm 11 of the rear suspension configured as described above and the first, second . Third lateral link 13. I/I.

If a solid connection is used, such as a ball joint, which does not allow any dimensional changes in the joints at both ends of 15, geometrically 6
All degrees of freedom are constrained and movement of the rear wheel 12 and wheel support 16 becomes impossible. For this reason, at least one part of each joint, swing arm, or lateral link itself is made flexible to absorb the amount of geometric interference that occurs when the wheel moves up and down.
Full rear wheel movement is possible.

Next, we will explain the control of toe changes when the vehicle bumps and rebounds with the rear suspension configured as described above. When bumping, the rear wheel 12 moves upwards relative to the vehicle body, and when it lands, it moves downwards. Moving. For this reason, 1. Each outer end 13a+14a+ of the second and third lateral links 13.14+15],
5a has each link as a radius, and each inner end 13b, 1
The robot moves along arc-shaped trajectories shown by broken lines E, F, and Q in the figure, centered on 4b and 15b. For this reason, each outer end 1
3 a + ], 4 a + 15 a is a circular arc-shaped broken line E.

F, G K move up and down and move inward to the vehicle body. At this time, since each link has a different length, the amount of movement inward to the vehicle body also differs, and the first lateral link 13 has the shortest link length. [outer end], 3a has the maximum amount of movement, and the longest amount of movement of the outer end 15a of the third lateral link 15 has the smallest amount of movement. Since the first lateral link 13 is located further forward of the vehicle body than the second and third lateral links 14.15,
The front end of the rear wheel 12 is pulled inward. That is, the outer edge 13 a + 14 a H
15a move inward to the vehicle body, the center of the wheel also moves inward, and the swing arm IJ is rotated around the base end 11ai, as shown in the examples of FIGS. 1 to 3, and the wheel toes out. However, this can be offset by the toe-in change caused by the above-mentioned link length difference. In other words, by appropriately setting the length of each link, it is possible to fully control toe changes during bumps and rebounds.

Next, camber changes at bumps and rebounds IIJ will be explained. To create a negative camber when bumping, use the second lateral recess as shown in Figure 6.
4 inner end 141] Just move it all the way down. However, simply lowering the inner end 1.41)'c in the vertical direction tends to create too much negative camber when the bump is large, and conversely tends to increase the positive camber during rebound. Therefore, in this embodiment, the inner end 14b is moved toward the front of the vehicle relative to the outer end 14-a. In this way, when bumping (C is wheel servo) 16 moves in an arc-shaped trajectory with the base end 11a'ff of the swing arm as the center, so it moves upward with respect to the vehicle body and K moves forward. It also moves. At this time, as the wheel support 16 moves upward, the second
The outer end 14a of [lateral link] 4 also has a trajectory P shown in FIG.
As it moves upward along K, it is pulled inward into the vehicle body, giving the tire a negative (7) camber f. At the same time, as the wheel support moves toward the front of the vehicle, the inner end 14a of the second lateral link 14 is moved toward the front of the vehicle. For this reason,
As shown in FIG. 5, when the inner end 14a moves forward, the second
Inner end 14. by lateral link ■4. a is pushed outward, giving the tire a positive camber.

In this way, the negative camber caused by the above-mentioned upward movement of the wheel support and the wheel ") - Ho ) (D
Combined with the positive camber generated by forward motion, the amount of negative gamba at the time of bump can be made positive. Figure 7 is a graph showing the camber change at the time of bump and one rebound. Bump amount on the positive side,
The negative side represents the entire amount of rebound, and the vertical axis represents the entire camber.In this graph, the solid line V represents the entire ideal curve of camber change required from the point of view of running performance and stability, and the dashed line vI represents the second lateral. inner end of link 14], 4 b
'i All the camber changes are shown when the inner end 141 of the second lateral link 14 is moved downward relative to the outer end 14a. The camber change in the case of the moved suspension of this embodiment is shown. As can be seen from this graph, the inner end of the second latent link], 4
b If the tire is moved too far in the fT direction, the negative camber at the time of a bump becomes too large, which may lead to uneven tire wear, and the positive camber becomes too large at the time of rebound, which may make driving unstable. be.

On the other hand, in the case of the rear suspension suspension of the present invention, a camber change V■ close to the ideal curve V can be obtained.

FIG. 8 is a side view of a preferred embodiment of the rear suspension suspension according to the present invention, as viewed from the side of the vehicle body. In the figure, the left side indicated by the arrow shows the entire front of the vehicle body, and the outer ends 13 a + 14 of the three lateral links connected to the wheel support 16
a p], 5 a, the outer end 13a in this figure
A straight line S1 passes through the centers of 1 and 4a, and a straight line S2 passes through the centers of the outer ends 14a and 1.5a.

Each straight line S1. Assuming that all the intersections between S2 and the road surface are Y and Z, respectively, the input point of the lateral force acting on the wheel 12 during driving is (
This point is located slightly behind the ground contact point when the vehicle is running.

)X is located between the intersection points Y and Z.

In this way, when a lateral force acts on the wheel 12, the second lateral link 14 located above receives a tensile force, and the first and third lateral links 13 and 15 located below receive a compressive force. The two links receive compressive force, which reduces the allowable load due to buckling, etc., and the tensile force, which has a large allowable load (i = one link receives it, so the load sharing between each link is optimized. Become.

In the embodiment described above, the coil spring and damper unit are attached to all wheel supports, but instead, they can be attached to any of the lateral links or the swing arm. moreover,
In the case of rear-wheel drive vehicles, it is possible to have the drive shaft pass through the wheel support.
It is also possible to reverse the front and rear of the suspension pen to make it a leading arm type instead of a trailing arm type.
It is possible to increase the lateral rigidity of the suspension suspension and to reduce the weight by using the suspension, and it is possible to perform both toe control and yaw and swing control. Furthermore, by optimizing camber changes during bumps and rebounds, uneven tire wear can be suppressed and the running stability of the vehicle can be completely improved.

[Brief Description of the Drawings] Figures 1 to 3 are views showing an example of a conventional rear suspension, in which Figure 1 is a perspective view, Figure 2 is a plan view, and Figure 3 is a front view. . 4 to 6 show one embodiment of the rear suspension of the present invention, in which FIG. 4 is a perspective view, FIG. 5 is a plan view, and FIG. 6 is a front view. FIG. 7 is a graph showing camber changes during bumps and rebounds, and FIG. 8 is a side view showing one embodiment of the rear suspension of the present invention. 1.11... Swing arm 2, 12... Rear Wheel 13...First lateral link 14...
...Second lateral link 15...Third lateral link 16...Whinonna sword ← 17
a = Coil spring 171) - Damper unit Fig. 1 @ 2 Fig. 1/1 Fig. 3 Fig. 4 Fig. 6

Claims (1)

[Scope of Claims] 1) A wheel support that rotatably supports a rear wheel; a base end attached to the vehicle body and a distal end attached to the wheel support, disposed in the longitudinal direction of the vehicle body, and the distal end located at the entire center of the base end; a swing arm that is swingable in the vertical direction of the vehicle body and receives rotational force from the rear wheel and front and rear; each outer end is connected to three mutually separated points of the wheel support, and each inner end is connected to the vehicle body It consists of three lateral links that are connected to three points separated from each other and arranged in the lateral direction of the vehicle body, and the outer end connection point of one of these three lateral links is located at the front and rear of the vehicle body. The inner end side connection point of this upper lateral link is located below the vehicle body than the outer end side connection point of the upper lateral link, and A car suspension system characterized by being placed at the front.2)
In a vertical projection plane extending in the longitudinal direction of the vehicle body, between two straight lines passing through the outer end connecting point of the upper lateral link and the outer end connecting point of the other two lateral links. 2. The rear suspension for an automobile according to claim 1, wherein the three lateral links are arranged such that a point of input of lateral force to the rear wheel is located.