JP4592226B2 - Independent suspension - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an independent suspension that suspends a vehicle wheel from a vehicle body for each wheel.
[0002]
[Prior art]
In the independent suspension type, a wheel support member (hub carrier) to which a wheel is attached is connected to the vehicle body using an arm or a link for each wheel. The wheel support member is attached to the vehicle body via a lower arm or an upper arm. The lower arm has two front support points (front support point and rear support point) that serve as attachment parts to the vehicle body due to space constraints with the fuel tank etc., and the front support point is located outside the rear support point. May be placed. In such a case, of the two connection points (the front connection point and the rear connection point) that are the attachment portions to the lower arm of the wheel support member, the front connection point is disposed on the vehicle outside of the rear connection point, The swing axis of the lower arm formed by the support points and the swing shaft of the wheel support member formed by the two connecting points are made substantially parallel. A rubber bush or the like is interposed between the support point and the connection point described above, and the bush shaft is made to coincide with the swing axis direction described above.
[0003]
[Problems to be solved by the invention]
By the way, the rubber bush is easily deformed in the direction of the bush axis itself due to its structural factors, and is not easily deformed in a direction perpendicular to the bush axis. For this reason, when a load in the front-rear direction is applied to the wheel, the suspension is difficult to deform in a direction perpendicular to the bushing axis, so that the rigidity in the front-rear direction of the suspension is hard and the riding comfort is deteriorated. On the other hand, when a lateral load is applied to the wheel, the suspension is easily deformed in the axial direction of the bush, and the lateral rigidity of the suspension is soft and the steering stability is deteriorated.
[0004]
An object of the present invention is to provide an independent suspension type suspension that can improve the ride comfort by softening the longitudinal rigidity of the suspension and can improve the steering stability by hardening the lateral rigidity of the suspension. .
[0005]
[Means for Solving the Problems]
The independent suspension of the present invention is connected to a lower arm supported by a vehicle body, and has a wheel support member that rotatably supports a wheel. The wheel support member has two points: a front connection point and a rear connection point. in which is coupled to the lower arm, located outside the vehicle body than the front connecting point rear connecting point, a linking point which front connecting point and a rear connecting point via a bush, respectively, front connecting point and after The bushing shafts of both bushes at the side connection point are made to coincide with the vehicle longitudinal axis, the first connection point is provided with a first stopper for restricting the rearward movement of the wheel support member, and the front side of the wheel support member is provided at the rear connection point. A second stopper for restricting movement is provided .
[0006]
According to the independent suspension of the present invention, the bush axis is aligned with the longitudinal axis of the vehicle, so that the displacement of the wheel in the lateral direction of the vehicle due to the compliance of the bush is suppressed, and the lateral rigidity of the suspension is hardened to stabilize the steering. Can be improved. At the same time, by aligning the bush axis with the longitudinal axis of the vehicle, it is possible to promote the displacement of the wheel in the longitudinal direction of the vehicle due to the compliance of the bush, and to improve the riding comfort by softening the rigidity in the longitudinal direction of the suspension. it can.
Further, the bushing shafts of both the front connection point and the rear connection point are made to coincide with the vehicle longitudinal axis, and a first stopper for restricting the rearward movement of the wheel support member is provided at the front connection point. Is provided with a second stopper for restricting the forward movement of the wheel support member. In this case, since the distance from the wheel to each connecting point is different, the moment acting on the wheel when a backward load acts on the wheel acts on the wheel when the forward load acts on the wheel. It is smaller than the moment, suppresses the toe change to the toe-out side during braking, and can secure a large toe-in change to the toe-in side during driving, which improves vehicle stability during braking and driving. Can be improved.
[0007]
Here, it is preferable to form currants on the upper and lower portions of the bush, with the bush shaft approaching the vehicle longitudinal axis. By doing in this way, durability with respect to the twist of a bush can be improved, and durability of a bush can also be improved with the coexistence of the above-mentioned riding comfort improvement and steering stability improvement.
[0008]
It is also preferable to embed the interleaf in the horizontal portion of the bush where the bush shaft is close to the vehicle longitudinal axis. By doing so, it is possible to further suppress deformation in the direction perpendicular to the bush axis of the bush, improve the lateral rigidity of the bush, and realize further improvement in steering stability.
[0009]
In addition, although it is preferable to use together the formation of the currant mentioned above, and embedding of interleaf, it is not necessary to use together. Even if they are not used in combination, the respective effects described above can be obtained.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of an independently suspended suspension according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view of a suspension (left rear wheel) according to the first embodiment. FIG. 2 is a side view of the bush 10a at the connection point from the direction of arrow A in FIG. In addition, not only the lower arm 6 shown in the figure but also the upper arm are connected to the wheel support member (hub carrier) 4 of the suspension shown in FIG. 1, but the connection point of the wheel support member 4 with the lower arm 6 ( In order to show the state of the bushes 8a, 10a) in an easy-to-understand manner, illustration of the connection points with the upper arm is omitted.
[0013]
As shown in FIG. 1, the wheel 2 is rotatably attached to the wheel support member 4. The wheel support member 4 is connected to the lower arm 6 through two connection points (a front connection point and a rear connection point) that are separated in the longitudinal direction of the vehicle body. The wheel support member 4 and the lower arm 6 are connected via a bush 8a at the front connection point, and the rear connection point is connected via a bush 10a. The lower arm 6 is supported on the vehicle body side at two support points (a front support point and a rear support point) separated in the vehicle longitudinal direction. That is, the lower arm 6 is supported by the vehicle body via the bush 12 at the front support point, and is supported via the bush 14 at the rear connection point.
[0014]
One of these bushes 8a, 10a, 12, and 14 (for example, the wheel support member 4 side) has a cylindrical cylindrical body, and the other (for example, the lower arm 6 side) is positioned at the center of the cylindrical body. It has a rod-like body (may be a small-diameter cylindrical body), and a rubber bush is interposed between them. In the bushes 8a and 10a, the wheel support member 4 side has a cylindrical body and the lower arm 6 side has a rod-like body, but these may be reversed. In the bushes 12 and 14, the lower arm 6 side has a cylindrical body and the vehicle body side has a rod-like body, but these may be reversed.
[0015]
As described above, the lower arm 6 is supported by the vehicle body via the bushes 12 and 14, but the bush 12 corresponding to the front support point is located on the outer side of the vehicle body than the bush 14 corresponding to the rear support point. Yes. The lower arm 6 has a front arm 6 a extending toward the front bush 12 and a rear arm 6 b extending toward the rear bush 14. The rear arm 6b is formed separately and is connected to the main body of the lower arm 6 by welding or bolts and nuts. The lower arm 6 has bushes 8a and 10a for connecting the wheel support member 4 to the wheel 2 side.
[0016]
The bushes 8a and 10a are formed between the wheel support member 4 and the lower arm 6, and the bush 8a corresponding to the front connection point is located on the outer side of the vehicle body with respect to the bush 10 corresponding to the rear connection point. These bushes 8a and 10a are formed below the wheel support member 4, and the wheel support member 4 also has a bush (not shown) serving as a connection point to an upper arm (not shown) on the upper side. is doing. The wheel 2 is rotatably attached to the wheel support member 4 via a hub. Here, the swing axis of the lower arm 6 passing through the two support points and the swing axis Xh below the wheel support member 4 passing through the two connection points are parallel to each other.
[0017]
The bush shaft of the bush 8a corresponding to the front connection point is configured to substantially coincide with the swing axis Xh. However, the bush axis Xbr of the bush 10a corresponding to the rear connection point is closer to the longitudinal axis of the vehicle than the swing axis Xh. In particular, the bush axis Xbr of the bush 10a in this suspension is made to substantially coincide with the vehicle longitudinal axis that is the vehicle body center line passing through the vehicle center and extending in the longitudinal direction. Due to the structure of the bush 10a, deformation in the direction of the swing axis Xh is likely to occur, and deformation in a direction perpendicular to the swing axis Xh is unlikely to occur. For this reason, the displacement of the wheel support member 4 due to the compliance deformation of the bush 10a is larger in the vehicle front-rear direction than in the conventional case where both the front and rear bush shafts are parallel to the swing axis Xh. Smaller in the lateral direction of the vehicle. As a result, the lateral rigidity of the suspension becomes hard and the steering stability is improved. At the same time, the rigidity of the suspension in the front-rear direction is softened, and the ride comfort is improved.
[0018]
Further, in the present embodiment, the bush 10a has a structure as shown in FIG. That is, the rubber part of the bush 10a is formed with currants 16 at the upper and lower parts thereof. The currant 16 is a hole penetrating in the vehicle front-rear direction along the bush axis Xbr. Since the bush axis Xbr of the bush 10a has an angle with respect to the swing axis Xh, it becomes easy to be twisted. Therefore, from the viewpoint of durability, the bush axis Xbr and the swing axis Xh are more aligned than the case. It becomes severe. Thus, by forming a pair of currants 16 on the upper and lower portions of the bush 10a with the bush shaft approaching in the vehicle longitudinal direction, durability against torsion of the bush 10a can be improved. The durability of the bush 10a can be improved along with the improvement of stability. In addition, the upper and lower parts referred to here mean the upper side and the lower side with respect to the center of the bush 10a, and it does not mean that the currants 16 must be arranged strictly along the vertical line.
[0019]
Further, an interleaf 18 is embedded in the horizontal portion of the rubber portion of the bush 10a. The interleaf 18 is a metal plate that is disposed along the bush axis Xbr in the vehicle front-rear direction, and has an effect of suppressing deformation of the bush 10a in the lateral (horizontal) direction by being embedded in the rubber portion. In this way, by embedding the interleaf 18 in the horizontal portion of the bush 10a with the bush shaft approaching in the vehicle longitudinal direction, the horizontal rigidity of the bush 10a is further improved, and the steering stability is further improved. can do. In addition, the horizontal part said here means the both sides with respect to the center of the bush 10a, and does not say that the interleaf 18 must be arrange | positioned exactly along a horizontal line.
[0020]
Next, a second embodiment of the present invention will be described. The present embodiment is in accordance with the first embodiment described above. For this reason, the same code | symbol is attached | subjected about the component same or equivalent to 1st Embodiment, and the detailed description is abbreviate | omitted.
[0021]
FIG. 3 is a plan view of an independent suspension (left rear wheel) according to the second embodiment of the present invention. In the present embodiment, the bush axis Xbf of the bush 8b corresponding to the front connection point is closer to the longitudinal axis of the vehicle than the swing axis Xh of the wheel support member 4. In particular, the bush axis Xbf of the bush 8b in this suspension is configured to substantially coincide with the vehicle longitudinal axis that passes through the center of the vehicle and extends along the longitudinal direction. The bush axis of the bush 10b corresponding to the rear connection point is substantially coincident with the swing axis Xh. As described above, the displacement of the wheel support member 4 due to the compliance deformation of the bush 8b can be reduced between the front side and the rear side as in the prior art by bringing the bush axis Xbf of the front bush 8b instead of the rear side closer to the vehicle longitudinal axis. Compared with the case where both bushing shafts are parallel to the swing axis Xh, it can be made larger in the vehicle front-rear direction and smaller in the vehicle lateral direction. As a result, the lateral rigidity of the suspension can be hardened and the steering stability can be improved. At the same time, the rigidity in the front-rear direction of the suspension can be softened and the riding comfort can be improved.
[0022]
In the present embodiment, the structure of the front bush 8b is the same as the structure of the bush 10b in the first embodiment (see FIG. 2). For this reason, the suspension of the present embodiment can also realize the effects of the above-described currant 16 and interleaf 18.
[0023]
Next, a third embodiment of the present invention will be described. This embodiment is also similar to the first embodiment described above. For this reason, the same code | symbol is attached | subjected about the component same or equivalent to 1st Embodiment, and the detailed description is abbreviate | omitted.
[0024]
FIG. 4 is a plan view of an independent suspension (left rear wheel) according to the third embodiment of the present invention. In the present embodiment, both the bush axis Xf of the bush 8c corresponding to the front connection point and the bush axis Xr of the bush 10c corresponding to the rear connection point are more vehicles than the swing axis Xh of the wheel support member 4. It is close to the vehicle rearward axis passing through the center and along the front-rear direction. In particular, both of the bush axes Xf and Xr in this suspension are made to substantially coincide with the vehicle longitudinal axis. As described above, the displacement of the wheel support member 4 due to the compliance deformation of the bushes 8c and 10c is caused by bringing both of the two bush shafts Xf and Xr closer to the vehicle longitudinal axis along the longitudinal direction passing through the center of the vehicle. Compared to the first embodiment and the second embodiment, the vehicle can be made larger in the vehicle front-rear direction and smaller in the vehicle lateral direction. As a result, the lateral rigidity of the suspension becomes harder and the steering stability can be further improved, and at the same time, the rigidity in the front-rear direction of the suspension becomes softer and the riding comfort can be further improved.
[0025]
In the present embodiment, the structure of the two bushes 8c and 10c is the same as the structure of the bush 10b in the first embodiment (see FIG. 2). For this reason, the suspension of the present embodiment can also realize the effects of the above-described currant 16 and interleaf 18.
[0026]
Further, in the present embodiment, as shown in FIG. 5, when a rearward load is applied to the wheel 2 (for example, during braking), the bush is brought into contact with the lower arm bracket 6c in association with the front bush 8c. A first stopper 20 that restricts the backward movement of 8c is provided. Here, the first stopper 20 is formed by extending the rubber bush of the bush 8c between the lower arm bracket 6c. Similarly, when a forward load is applied to the wheel 2 in association with the rear bush 10c (for example, during acceleration / driving), the lower arm bracket 6d is abutted to restrict the forward movement of the bush 10c. A second stopper 22 is provided. Here, the second stopper 22 is obtained by extending the rubber bush of the bush 10c between the lower arm bracket 6d.
[0027]
When a backward load is applied to the wheel 2, the lower arm bracket 6c and the first stopper 20 come into contact with each other, and a moment M1 in FIG. 4 is generated. On the other hand, when a forward load is applied to the wheel 2, the lower arm bracket 6d and the second stopper 22 come into contact with each other, and a moment M2 in FIG. 4 is generated. At this time, if the forward load and the backward load are equal, (distance between the center line of the wheel 2 and the bush 8c: Lf) <(distance between the center line of the wheel 2 and the bush 10c: Lr) Therefore, M1 <M2. That is, as far as the wheel support member 4 is concerned, it is possible to suppress a toe change amount toward the toe-out side of the wheel 2 at the time of a backward load, and to ensure a large toe change amount to the toe-in side at the time of a forward load. Can be improved. (The final toe change amount of the actual wheel 2 is determined by the influence of the compliance steer of the bushes 12 and 14 between the lower arm 6 and the vehicle body.)
The independent suspension of the present invention is not limited to the above-described embodiment. For example, in the above-described embodiment, the bush axis Xf and the bush axis Xr are almost coincident with the vehicle longitudinal axis along the longitudinal direction passing through the center of the vehicle in each case. It does not have to be, but rather is closer to the vehicle longitudinal axis along the longitudinal direction passing through the center of the vehicle than the swing axis Xh of the wheel support member 4 (more parallel to the longitudinal axis of the vehicle). It only has to be.
[0028]
【The invention's effect】
According to independent suspension of the present invention, with the bush axis to match the vehicle longitudinal axis along the longitudinal direction through the vehicle center than the pivot shaft of the wheel support member, lateral rigidity of the wheel support member Since it is hard and soft in the front-rear direction, it is possible to achieve both improved driving stability and improved ride comfort.
[Brief description of the drawings]
FIG. 1 is a plan view of an independent suspension (left rear wheel) according to a first embodiment of the present invention.
FIG. 2 is a side view of a rear bushing of a wheel support member in the suspension shown in FIG.
FIG. 3 is a plan view of an independent suspension (left rear wheel) according to a second embodiment of the present invention.
FIG. 4 is a plan view of an independent suspension (left rear wheel) according to a third embodiment of the present invention.
FIG. 5 is a diagram showing a configuration of a stopper according to a third embodiment of the present invention.
[Explanation of symbols]
2 ... wheels, 4 ... wheel support members, 6 ... lower arm, 6a ... front arm, 6b ... rear arm, 8a, 8b, 8c, 10a, 10b, 10c, 12, 14 ... bush, 16 ... currant, 18 ... inter Leaf, 20 ... first stopper, 22 ... second stopper.

Claims (3)

In an independent suspension having a wheel support member connected to a lower arm supported by the vehicle body and rotatably supporting a wheel,
The wheel support member is connected to the lower arm at two points of a front side connection point and a rear side connection point, the front side connection point is located outside the vehicle body with respect to the rear side connection point, and the front side connection point and Each of the rear side connection points is a connection point via a bush,
The bush axes of the bushes at both the front connection point and the rear connection point are made to coincide with the vehicle longitudinal axis,
The front connection point is provided with a first stopper for restricting rearward movement of the wheel support member, and the rear connection point is provided with a second stopper for restricting forward movement of the wheel support member. Independent suspension type suspension.   2. The independent suspension type suspension according to claim 1, wherein a curly portion is formed on the upper and lower portions of the bush with the bush shaft approaching the vehicle longitudinal axis.   The independent suspension type suspension according to claim 1 or 2, wherein an interleaf is embedded in a horizontal portion of the bush where the bush shaft is close to the vehicle longitudinal axis.

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