JP3105073B2 - Vehicle suspension device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle suspension system.

[0002]

2. Description of the Related Art Conventionally, as a vehicle suspension device, a strut type and a double wishbone type are generally well known, and are often used in actual vehicles.

However, in the strut type suspension device, the virtual kingpin axis, which is the steering rotation axis of the wheel, is a straight line connecting the connection point between the upper end of the damper device and the vehicle body and the connection point between the lower arm and the wheel support member. However, this virtual kingpin axis is not desirable in terms of vehicle performance. In other words, from the viewpoint of vehicle performance, the virtual kingpin axis is
Ideally, the wheel slightly passes through the inside of the vehicle body than the center line in the width direction of the wheel on the rotation center line of the wheel, and passes slightly outside the vehicle body from the center line in the width direction of the wheel so as to have a slight negative kingpin offset on the ground contact surface of the wheel. However, this is because the virtual kingpin axis of the strut-type suspension device is inclined more inwardly than the ideal virtual kingpin axis.

On the other hand, in a double wishbone type suspension device, the virtual kingpin axis is
A straight line connecting the connection point between the upper arm and the wheel support member and the connection point between the lower arm and the wheel support member can be brought closer to the ideal virtual kingpin axis by appropriately setting the two connection points. However, in the case of the double wishbone type, two connection points of the upper arm and the lower arm with the vehicle body are required to counter the horizontal load acting on the wheels, etc., and the arrangement setting of other parts Is limited. In particular, when this double wishbone type suspension device is used as a front wheel suspension device for an FF type vehicle, this layout limitation becomes an important problem. In addition, in the strut type suspension device,
Since there is no upper arm, the layout problem is small.

[0005] In order to combine the advantages of the conventional strut type and the double wishbone type and to eliminate the disadvantages, a number of suspension devices have been proposed. Conventional example will be described with reference to a gazette.

A first conventional example is disclosed in Japanese Patent Laid-Open No. 2-220904.
This is disclosed in Japanese Patent Application Publication No. This conventional example basically belongs to the improved type of the double wishbone type, in which the upper arm is constituted by one link member, and the lower end of the damper device is connected to the lower arm to act on the wheels. The load is also supported by the damper device. According to this conventional example, since there is only one connection point between the upper arm and the vehicle body, the degree of freedom in layout can be increased accordingly.

A second conventional example is disclosed in DE 3839463A1.
It is disclosed in a gazette. In this conventional example, as in the first conventional example, the upper arm is formed by one link member, while the lower end of the damper device is connected to the wheel support member. It has the advantage that the degree can be increased.

A third conventional example is disclosed in Japanese Patent Application Laid-Open No. 1-136804.
This is disclosed in Japanese Patent Application Publication No. This conventional example also basically belongs to the improved type of the double wishbone type, in which an intermediate member is provided between the wheel support member and the upper arm, and the lower end of the damper member is connected to the intermediate member. Further, the wheel supporting member is connected to the intermediate member via a ball joint, and the upper arm is connected so as to be rotatable only around the longitudinal axis.

[0009]

However, the above-described first to third conventional examples also have the following disadvantages. That is, in the first conventional example, in particular, F
When used as a front suspension device for an F-type vehicle, a lower end of the damper device and a lower arm are provided in order to avoid interference between a drive shaft extending in the vehicle width direction on the rotation center line of the wheel and a damper device connected to the lower arm. It is necessary to provide a bifurcated connecting member through which the drive shaft passes, but this connecting member needs to have great rigidity because it receives all the forces generated by the damper device. For this reason, there is a disadvantage that the connecting member is large and heavy, which causes an increase in the weight of the entire apparatus.

In the second conventional example, since the wheel supporting member must also form an arm for connecting to the damper device, there is a disadvantage that the shape is complicated and the weight increases. Further, since the lower end of the damper device extends below the rotation center line of the wheel, in the case of an FF type vehicle, it is necessary to avoid interference between the damper device and the drive shaft, and the layout is accordingly free. The degree decreases. Further, there is a disadvantage that the virtual kingpin axis is considerably inclined upward and inward of the vehicle body, which is far from the ideal one.

In the third conventional example, since the wheel supporting member and the intermediate member are connected by the ball joint, the horizontal load (lateral force, longitudinal force) acting on the wheel cannot be received by the damper device. . For this reason, the connection point of the upper arm with the vehicle body is 2
Points are required, and the degree of freedom in layout cannot be increased.

The present invention has been made in view of the above-mentioned points, and an object of the present invention is to improve the performance by bringing a virtual kingpin shaft closer to an ideal one like the double wishbone type while improving the performance. It is an object of the present invention to provide a vehicle suspension device capable of achieving a reduction in size and weight, an improvement in layout flexibility, and the like.

[0013]

According to a first aspect of the present invention, there is provided a suspension apparatus for a vehicle, comprising: a wheel support member for rotatably supporting a wheel; and a lower end provided at one end of the wheel support member. A lower arm, the other end of which is connected to the vehicle body so as to be able to swing up and down, a connecting member which is connected to the upper end of the wheel support member so as to be rotatable only around the vertical axis, and one end of which is connected to the vehicle body at one point. The other end is connected to the connecting member so as to be rotatable only around the longitudinal axis, the upper end is connected to the vehicle body, and the lower end is rotatably connected only around the longitudinal axis at an intermediate portion of the upper arm. And a damper device.

The inventions of claims 2 and 3 are both dependent on the invention of claim 1 and more specifically show them.

That is, in order to make the virtual kingpin axis closer to the ideal one, the lower arm is constituted by two front and rear link members, and one end of each link member is connected to the wheel support member. The other end is connected to the vehicle body at the lower end, and the two link members are arranged so that their axes intersect outside the vehicle body from the connection point with the wheel support members.

According to a third aspect of the present invention, a pair of bifurcated branch portions are provided from the middle portion of the upper arm to the end portion on the connecting member side, and a damper device is sandwiched between the two branch portions. In this state, the upper arm is connected to the damper device, and the distal ends of both branch portions are connected to the connecting members.

[0017]

According to the above-mentioned structure, according to the first aspect of the present invention,
Since the lower end of the damper device is connected to the middle portion of the upper arm and does not extend downward to near the rotation center line of the wheel, even in the case of the FF type vehicle, the damper device does not interfere with the drive shaft. It is not necessary to adopt a special structure for avoiding interference. Also, by connecting the damper device to the intermediate portion of the upper arm,
The amount of vertical displacement at the time of bump rebound of the wheel is ensured to be larger than the amount of expansion and contraction of the damper device. Further, since the upper arm is connected to the vehicle body at only one point, the degree of freedom in layout is increased accordingly.

In addition, the camber change characteristics can be set to be equal to or greater than that of a double wishbone type suspension device with a strut type suspension device or more.

According to the second aspect of the present invention, when the wheel is steered, the instantaneous center of rotation of the wheel supporting member or the upper side of the wheel is determined by the fact that the wheel supporting member is rotated about the vertical axis of the connecting portion with the connecting member. And the structure composed of the damper device and the upper arm is displaced around a straight line connecting the vehicle body connection point at the upper end of the damper device and the vehicle body connection point of the upper arm. The intersection with the straight line is located at a position closer to the center line side of the wheel in the vehicle width direction. On the other hand, the instantaneous rotation center point on the lower side of the wheel support member is the intersection of the axes of the two link members constituting the lower arm. Therefore, the virtual kingpin axis is a straight line passing through the above-mentioned two instantaneous rotation center points, but this virtual kingpin axis is shifted toward the center line side of the vehicle in the vehicle width direction and is more ideal than a double wishbone type suspension device. Will approach.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show an embodiment of the present invention.
1 shows a suspension device for a front wheel of an F-type vehicle, wherein 1 is a knuckle member as a wheel support member for rotatably supporting a wheel (front wheel) 2.
An insertion port 3 through which a drive shaft (not shown) is inserted is formed. 4 is a lower arm connecting the lower end of the knuckle member 1 to the vehicle body side, 5 is an upper arm connecting the upper end of the knuckle member 1 to the vehicle body side, and 6 is a damper device comprising a shock absorber for buffering the vertical movement of the wheels 2. .

The lower arm 4 includes two front and rear link members 11 and 12, and the front link member 11 extends substantially linearly in the vehicle width direction. One end (outer end) of the link member 11 is The other end (inner end) of the link member 11 is connected to a lower end of the knuckle member 1 via a ball joint 13 and a rubber bush 15 whose axis extends in the front-rear direction of the vehicle body with respect to the cross member 14 which is a vehicle body strength member. Are connected so as to be able to swing up and down. The rear link member 12 is formed in a curved shape, and one end (outer end) of the link member 12 is connected to the connection point of the link member 11 at the lower end of the knuckle member 1 (the center of the ball joint 13). The other end (inner end) of the link member 12 is connected to the cross member 14 at a position far away from the link member 11 by a rubber bush 17. Are connected so as to be able to swing up and down. Therefore, the axes of the link members 11 and 12 are aligned with each other by the knuckle member 1.
At the point O1 outside the vehicle body from the connection point (the center of the ball joints 13 and 16).

The knuckle member 1 is integrally formed with an arm portion 1a extending rearward from the vicinity of the insertion opening 3, and a tie rod 20 of a steering device is provided at the tip of the arm portion 1a.
Are connected. A connecting member 21 is mounted on the upper end of the knuckle member 1 and the connecting member 21
Is connected to the outer end of the upper arm 5.

The upper end of the knuckle member 1 and the connecting member 21
As shown in detail in FIG. 4, a vertical shaft 23 extending vertically is attached to the upper end of the knuckle member 1, and a sleeve member 24 is fitted on the outer periphery of the vertical shaft 23. . On the outer peripheral surface of the sleeve member 24, a cylindrical surface 24a, an upper conical surface 24b which is continuous with the upper end of the cylindrical surface 24a and gradually expands in diameter as going upward, and which is continuous with and lower than the lower end of the cylindrical surface 24a. A lower conical surface 24c that gradually increases in diameter toward the side is formed, and a first boss portion 21a of the connecting member 21 is rotatably fitted to the outer peripheral surface of the connecting member 21 via a bush 25 made of resin. ing. On the inner peripheral surface of the first boss portion 21a, a cylindrical surface 21b, an upper conical surface 21c, and an upper conical surface which face the cylindrical surface 24a, the upper conical surface 24b, and the lower conical surface 24c of the sleeve member 24 at a predetermined distance, respectively. The surface 21d is formed. Therefore, the connecting member 21 is provided so as to be rotatable only about the vertical shaft 23 with respect to the upper end of the knuckle member 1, and the sleeve member 24 is provided for a rotational force about an axis orthogonal to the vertical shaft 23. And the inner peripheral surface of the first boss portion 21a.

On the other hand, the inner end of the upper arm 5 is connected to a bracket 31 mounted on the cross member 14 via a rubber bush 32 whose axis extends in the front-rear direction of the vehicle body so as to be vertically swingable at one point. I have. The upper arm 5 has a pair of branches 5a, 5a branched in a bifurcated manner from the middle part to the outer end side (that is, the connection end side with the connection member 21), and is provided between the two branch parts 5a, 5a. The damper device 6 is connected to the lower end of the damper device 6 with the damper device 6 interposed therebetween, and is connected to the connecting member 21 at the distal ends of the two branch portions 5a.

Further, the upper end of the damper device 6 is elastically supported by the vehicle body 7 via a rubber mount 36, and a coil spring 37 is disposed on the outer periphery of the upper portion of the damper device 6. A bracket 38 is fitted to the lower end of the damper device 6, and the lower end of the damper device 6 is connected to the intermediate portion of the upper arm 5 (the base end side of each branch 5 a) via the bracket 38.

At the connection between the connecting member 21 and the outer end of the upper arm 5 (specifically, the distal end of each branching portion 5a), as shown in detail in FIG. A front-rear shaft 39 penetrating in the vehicle front-rear direction is provided, and the ends of the branch portions 5 a of the upper arm 5 are connected to both ends of the front-rear shaft 39 via rubber bushes 33. A sleeve member 40 is fitted on the outer periphery of the front-rear shaft 39 so as to be sandwiched between the two branch portions 5a of the upper arm 5. The above sleeve member 4
0, a cylindrical surface 40a, a front conical surface 40b continuous with the front end of the cylindrical surface 40a and gradually increasing in diameter toward the front side, and continuous with the rear end of the cylindrical surface 40a and on the rear side. A rear conical surface 40c that gradually increases in diameter as it faces is formed. A second boss portion 21e of the connecting member 21 is rotatably fitted to the outer peripheral surface of the connecting member 21 via a bush 41 made of resin. I have. On the inner peripheral surface of the second boss portion 21e, the cylindrical surface 40a of the sleeve member 40, the front conical surface 40
cylindrical surface 21f, front side conical surface 21g, and rear side conical surface 2 facing each other at a predetermined distance from b and rear conical surface 40c, respectively.
1h is formed. Therefore, the connecting member 21 and the upper arm 5 are connected so as to be rotatable around the front-rear shaft 39 and to allow a relative displacement in a direction orthogonal to the front-rear shaft 39 by elastic deformation of the rubber bush 33. ing.

At the connecting portion between the lower end of the damper device 6 and the intermediate portion of the upper arm 5 (the base end side of each branch 5a), as shown in detail in FIG. Seats 38a, 38a each having a screw hole are formed on the bracket 38 mounted on the portion facing the inner surface of each branch 5a of the upper arm 5, and each of the branches 5a of the upper arm 5 has a rotary bearing. 42 are provided. Then, a fastening bolt 43 as a front-rear shaft is provided from the side of each branch portion 5a of the upper arm 5.
Through the rotary bearing 42 and the seat 38a
, The damper device 6 and the upper arm 5 are relatively rotatably connected around the axis of the fastening bolt 43.

The rubber bush 33 at the tip of the branch 5a of the upper arm 5 is connected to the branch 5 as shown in FIG.
a outer cylinder 33a fixed to the tip, an inner cylinder 33b arranged concentrically with the outer cylinder 33a and having the front-rear shaft 39 inserted therein, and an inner cylinder 33b between the outer cylinder 33a and the inner cylinder 33b. Intermediate cylinder 33c arranged concentrically with the rubber 3 filled between the three cylinders 33a to 33c.
3d and 33d. The rubber bushes 15, 17, 32 other than the rubber bush 33 are not shown, but are basically the same as the rubber bush 33, but there are those having an intermediate cylinder and those having no intermediate cylinder.

Next, the operation and effect of the above embodiment will be described. When the wheel 2 is steered left and right by receiving the steering force from the tie rod 20 via the knuckle member 1, the lower end of the knuckle member 1 That is, the instantaneous rotation center point on the lower arm 4 side corresponds to the two link members 1 constituting the lower arm 4.
This is the intersection O1 between the axes 1 and 12. The instantaneous rotation center point on the upper end side of the knuckle member 1 is
Is rotated about a vertical axis 23 which is a connection axis with the connection member 21, and a structure including the damper device 6 and the upper arm 5 is connected to a vehicle body connection point (a center point of the rubber mount 36) at an upper end of the damper device 6 and an upper arm. 5 from the vehicle connecting point (the center point of the rubber bush 32).
An intersection O2 between the line 2 and the straight line L1 is obtained. Therefore, the virtual kingpin axis is a straight line L3 passing through the two intersections O1, O2.
However, this virtual kingpin axis L3 comes closer to the widthwise center line L4 of the wheel 2 and rises substantially vertically, and the rotation center line L5 of the wheel 2 is larger than the center line L4 of the wheel 2 in the width direction. Since the vehicle slightly passes through the inside of the vehicle body and slightly passes through the outside of the vehicle body from the center line L4 in the width direction of the wheel 2 so as to have a slight negative kingpin offset (−Δ) at the ground contact surface of the wheel 2, the suspension performance is improved. Can be improved.

When the wheel 2 is bumped and rebounded, the lower arm 4 and the upper arm 5 are respectively connected to their vehicle body connection points (center points of the rubber bushes 15, 17, 32).
, And the wheel supporting member 1 or the wheel 2 performs a vertical bump / rebound operation. At this time, since the upper and lower ends of the wheel support member 1 are connected to the vehicle body via the lower arm 4 and the upper arm 5, the camber change characteristic of the wheel 2 is more than a strut type suspension device or a double wishbone type suspension device. It can be set to the same degree. Further, since the damper device 6 is connected to the intermediate portion of the upper arm 5, the vertical displacement amount (so-called suspension stroke) of the wheel 2 at the time of bump rebound is ensured to be larger than the expansion and contraction amount of the damper device 6. Can also.

In addition, the lower end of the damper device 6 is connected to the intermediate portion of the upper arm 5 and does not extend downward to near the rotation center line L5 of the wheel 2, so that the damper device 6 and the drive shaft interfere with each other. Never. Therefore, it is not necessary to adopt a special structure for avoiding the interference, and the structure can be simplified, and the device can be reduced in size and weight.

Further, since the upper arm 5 is connected to the vehicle body at only one point, the degree of freedom in layout can be increased accordingly.

It should be noted that the present invention is not limited to the above-described embodiment, but includes various other modifications.
For example, in the above-described embodiment, when connecting the connecting member 21 to the upper end of the knuckle member 1 so as to be rotatable only around the vertical axis 23, the sleeve member 24 and the resin bush 25 are used (see FIG. 4). However, according to the present invention, as shown in FIG. 6, the first member of the connecting member 21 is provided on the outer periphery of the vertical shaft 23 attached to the knuckle member 1 via bearings 51 and 52.
You may comprise so that the boss | hub part 21a may be fitted.

In the above embodiment, the connecting portion between the lower end of the damper device 6 and the intermediate portion of the upper arm 5
Bracket 38 attached to the lower end of damper device 6
Are formed with seat portions 38a, 38a each having a screw hole, and a rotary bearing 42 is provided at each of the branch portions 5a of the upper arm 5, and a fastening bolt 43 is provided from the side of each of the branch portions 5a of the upper arm 5, and the rotary bearing 42, the bracket 38 is screwed into the screw hole of the seat 38a. However, in the present invention, instead of this connection structure, the bracket 38 is moved from one branch portion 5a of the upper arm 5 in the vehicle longitudinal direction. The damper device and the upper arm 5 may be connected to each other so as to be relatively rotatable around the front-rear axis by a front-rear shaft extending to the other branch portion 5a of the upper arm 5 through the front arm.

Further, in the above embodiment, the present invention is applied to the FF
The case where the present invention is applied to a suspension device for a front wheel of a model car has been described.

[0037]

As described above, according to the vehicle suspension device of the present invention, the damper device and the drive shaft do not interfere with each other, and it is not necessary to adopt a special structure for avoiding the interference. Can be reduced in size and weight. Further, since the connection point of the upper arm with the vehicle body is only one point, the degree of freedom in layout can be increased accordingly. Further, since the camber change characteristics can be set to be equal to or more than the strut type and to the double wishbone type, the suspension performance can be improved.

In particular, according to the second aspect of the present invention, the instantaneous rotation center points on the upper side and the lower side of the wheel support member are shifted to the center line in the vehicle width direction of the wheel, and the virtual kingpin axis is aligned with the rotation center line of the wheel. Since it can pass closer to the ideal one passing slightly outside the vehicle than the center line in the width direction of the wheel so that it passes slightly inside the vehicle body than the center line in the width direction of the wheel and slightly negative kingpin offset on the ground contact surface of the wheel, Suspension performance can be further improved.

According to the third aspect of the present invention, by connecting the upper arm to the damper device and the connecting member at two points, the connection strength can be increased.

[Brief description of the drawings]

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

FIG. 2 is a front view in which a part is also cut away when viewed from the front of the vehicle body.

FIG. 3 is a plan view of the same.

FIG. 4 is a sectional view showing a connection structure between a knuckle member and a connection member.

FIG. 5 is a cross-sectional view illustrating a connection structure between an upper arm, a connection member, and a damper device.

FIG. 6 is a cross-sectional view showing a modification of the connection structure between the knuckle member and the connection member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Knuckle member (wheel support member) 2 Wheel (front wheel) 4 Lower arm 5 Upper arm 5a Branch 6 Damper device 11, 12 Link member 21 Connecting member 23 Vertical axis 39 Front-rear axis 43 Fastening bolt (Front-axis)

Claims (3)

(57) [Claims] A wheel support member rotatably supporting a wheel; a lower arm having one end connected to a lower end of the wheel support member and the other end connected to a vehicle body so as to be vertically swingable; A connecting member connected to the upper end so as to be rotatable only around the vertical axis, an upper arm having one end connected to the vehicle body at one point and the other end connected to the connecting member so as to be rotatable only around the front-rear axis; And a damper device having a lower end connected to the vehicle body and a lower end rotatably connected only around the front-rear axis at an intermediate portion of the upper arm. 2. The lower arm comprises two front and rear link members, one end of each link member being connected to a lower end of a wheel support member, and the other end being connected to a vehicle body, respectively. The vehicle suspension device according to claim 1, wherein the axes are arranged so that their axes intersect outside the vehicle body with respect to a connection point with the wheel support member. 3. The upper arm has a pair of branch portions that branch from an intermediate portion to an end portion on the connecting member side in a bifurcated manner, and the damper device is sandwiched between the two branch portions. The suspension device for a vehicle according to claim 1, wherein the vehicle suspension device is connected to the connecting member at both ends of the two branch portions.