JPH05319046A - Suspension device of vehicle - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve the performance by bringing the virtual kingpin axis closer to the ideal one, and to make it more compact, lighter, and more flexible in layout. [Structure] A lower end of a knuckle member 1 for rotatably supporting a wheel is connected to a vehicle body via a lower arm 4 so as to be vertically swingable. The connecting member 21 is connected to the upper end of the knuckle member 1 so as to be rotatable only around the vertical axis. The other end of the upper arm 5 whose one end is connected to the vehicle body at one point is connected to the connecting member 6 so as to be rotatable only around the front-rear shaft 39, and the upper end is connected to the vehicle body at the intermediate portion of the upper arm 5. The lower end of the damper device 6 is rotatably connected only around the front-rear shaft 43. Preferably, the lower arm is composed of front and rear two link members 11 and 12, and both link members are arranged so that their axes intersect with each other outside the vehicle body with respect to the connection point with the knuckle members.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art Conventionally, strut type and double wishbone type suspension devices are generally well known as vehicle suspension devices, and are widely 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 vehicle body at the upper end of the damper device 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, in terms of vehicle performance, the virtual kingpin axis is
Ideally, it should pass slightly inside the vehicle body from the center line in the wheel width direction on the wheel rotation center line, and slightly outside the vehicle body from the center line in the wheel width direction so that there is a slight negative kingpin offset on the ground contact surface of the wheel. However, the virtual kingpin axis of the strut-type suspension device is inclined toward the inside of the vehicle body with respect to the ideal virtual kingpin axis.

On the other hand, in the 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 close to the ideal virtual kingpin axis by appropriately setting both connection points. However, in the case of the double wishbone type, in order to counter the horizontal load acting on the wheels, it is necessary to connect two points each to the upper arm and the lower arm to the vehicle body. Is limited. In particular, when using this double wishbone type suspension device for the front wheels in an FF type vehicle, this layout limitation becomes an important issue. In addition, in the strut type suspension device,
Due to the structure without the upper arm, there are few problems in this layout.

Therefore, in order to combine the advantages of the conventional strut type and the double wishbone type and to eliminate the drawbacks, a number of suspension devices have been conventionally proposed. A conventional example will be described with reference to the publication.

The first conventional example is Japanese Patent Laid-Open No. 220904/1990.
It is disclosed in Japanese Patent Publication No. This conventional example basically belongs to an improved type of a double wishbone type, in which the upper arm is composed of one link member, while the lower end of the damper device is connected to the lower arm so that the wheel acts. The structure is such that the load can also be supported by the damper device. According to this conventional example, since there is only one connecting point between the upper arm and the vehicle body, the degree of freedom in layout can be increased accordingly.

The second conventional example is DE 3839463A1.
It is disclosed in the official gazette. In this conventional example, the upper arm is composed of one link member as in the first conventional example, while the lower end of the damper device is connected to the wheel supporting member. In this conventional example as well, the layout is free. It has the advantage of increasing the degree.

A third conventional example is Japanese Patent Laid-Open No. 1-136804.
It is disclosed in Japanese Patent Publication No. This conventional example also basically belongs to the improved double wishbone type, and 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 support 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 front-rear axis.

[0009]

However, the above-mentioned first to third conventional examples also have the following drawbacks. That is, in the first conventional example, in particular, F
When used as a front suspension device of an F-type vehicle, in order to avoid interference between a drive shaft arranged to extend in the vehicle width direction on the rotation center line of a wheel and a damper device connected to a lower arm, a lower end of the damper device and a lower arm are provided. It is necessary to provide a bifurcated connecting member through which the drive shaft is passed, but this connecting member receives all the force generated by the damper device, and therefore needs to have a large rigidity. Therefore, there is a drawback that the connecting member becomes large in size and heavy in weight, resulting in an increase in weight of the entire apparatus.

In the second conventional example, since the wheel supporting member also has to form an arm portion for connecting with the damper device, there is a drawback that the shape is complicated and the weight is increased. Further, since the lower end of the damper device extends below the wheel rotation center line, in the case of an FF type vehicle, interference between this damper device and the drive shaft must be avoided, and the layout is free accordingly. The degree becomes smaller. Further, there is a drawback that the virtual kingpin axis is tilted upwards inwardly, which is far from the ideal one.

In the third conventional example, since the wheel support 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 the same as the double wishbone type.
However, the degree of freedom in layout cannot be increased.

The present invention has been made in view of the above points, and an object of the present invention is to improve the performance by bringing a virtual kingpin shaft close to an ideal one as in the double wishbone type, An object of the present invention is to provide a vehicle suspension device that can be made compact, lightweight, and have improved layout flexibility.

[0013]

To achieve the above object, the invention according to claim 1 is, as a vehicle suspension device, a wheel support member for rotatably supporting a wheel, and one end of which is a lower end of the wheel support member. A lower arm connected to the vehicle body so that the other end is swingable up and down, a connecting member connected to the upper end of the wheel support member so as to be rotatable only around the vertical axis, and one end 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 front-rear axis, the upper end is connected to the vehicle body, and the lower end is connected to the middle portion of the upper arm so as to be rotatable only around the front-rear axis. And a damper device.

The inventions described in claims 2 and 3 are both dependent from the invention described in claim 1 and more specifically show this.

That is, in order to bring the virtual kingpin shaft closer to an ideal one, the lower arm is composed of two front and rear link members, and one end of each link member is a wheel support member. At the lower end, the other end is connected to the vehicle body, and the link members are arranged so that their axes intersect with each other outside the vehicle body with respect to the connection point with the wheel supporting members.

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

[0017]

With the above construction, in the invention according to claim 1,
Since the lower end of the damper device is connected to the middle part of the upper arm and does not extend downward to the vicinity of the center line of rotation of the wheels, the damper device and the drive shaft do not interfere with each other even in the FF type vehicle. There is no need to adopt a special structure for avoiding interference. Further, since the damper device is connected to the intermediate portion of the upper arm,
The amount of vertical displacement at the time of bump rebound of the wheel is secured to be larger than the amount of expansion and contraction of the damper device. Furthermore, since the number of connecting points of the upper arm to the vehicle body is only one, the degree of freedom in layout is increased accordingly.

In addition, the camber change characteristic can be set to the same level as that of the double wishbone type suspension device or more than the strut type suspension device.

According to the second aspect of the present invention, when the wheel is steered, the instantaneous center of rotation on the wheel supporting member or on the upper side of the wheel is about the vertical axis of the connecting portion of the wheel supporting member and the connecting member. As the structure consisting of the damper device and the upper arm is rotated about a straight line connecting the vehicle body connecting point of the upper end of the damper device and the vehicle body connecting point of the upper arm, the structure extending from the upper and lower shafts is extended. It is an intersection with the above straight line and 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 forming the lower arm. Therefore, the virtual kingpin axis is a straight line that passes through the two instantaneous center points of rotation, but this virtual kingpin axis is closer to the center line side of the vehicle in the vehicle width direction, and is more ideal than the double wishbone suspension system. Will approach.

[0020]

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

1 to 3 show an F according to an embodiment of the present invention.
A front wheel suspension device for an F-type vehicle is shown, in which 1 is a knuckle member as a wheel supporting member for rotatably supporting a wheel (front wheel) 2, and
An insertion port 3 for inserting a drive shaft (not shown) is formed. Reference numeral 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 including a shock absorber for buffering the vertical movement of the wheel 2. ..

The lower arm 4 is composed of two front and rear link members 11 and 12, the front side link member 11 extends substantially linearly in the vehicle width direction, and one end (outer end) of the link member 11 is formed. The rubber bush 15 is connected to the lower end of the knuckle member 1 via a ball joint 13, and the other end (inner end) of the link member 11 has an axis extending in the vehicle body front-rear direction with respect to the cross member 14 which is a vehicle body strength member. It is connected via an arrow so that it can swing up and down. The link member 12 on the rear side is formed in a curved shape, and one end (outer end) of the link member 12 has a connecting point of the link member 11 at the lower end of the knuckle member 1 (center of the ball joint 13). The other end (inner end) of the link member 12 is connected to a position close to the rear side via a ball joint 16, and the other end (inner end) of the link member 12 is far away from the link member 11 with respect to the cross member 14. It is connected via an arrow so that it can swing up and down. Therefore, the axes of the two link members 11 and 12 are different from each other in their knuckle member 1
It intersects at a point O1 on the outer side of the vehicle body from the connection point (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 thereof, and the tie rod 20 of the steering device is provided at the tip of the arm portion 1a.
Are connected. A connecting member 21 is attached to the upper end of the knuckle member 1, and the connecting member 21
The outer end of the upper arm 5 is connected to.

The upper end of the knuckle member 1 and the connecting member 21.
4, a vertical shaft 23 extending in the vertical direction 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 that is continuous with the upper end of the cylindrical surface 24a and gradually increases in diameter toward the upper side, and is continuous with the lower end of the cylindrical surface 24a and is lower than the lower surface. A lower conical surface 24c is formed which gradually expands in diameter toward the side, and the first boss portion 21a of the connecting member 21 is rotatably fitted to this outer peripheral surface via a resin bush 25. ing. The inner peripheral surface of the first boss portion 21a has a cylindrical surface 21b, an upper conical surface 21c, and an upper conical surface that 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. The surface 21d is formed. Therefore, the connecting member 21 is provided so as to be rotatable only around the vertical axis 23 with respect to the upper end of the knuckle member 1, and the sleeve member 24 is provided with respect to the rotational force around the axis orthogonal to the vertical axis 23. The outer peripheral surface and the inner peripheral surface of the first boss portion 21a are brought into surface contact to resist.

On the other hand, the inner end of the upper arm 5 is connected to a bracket 31 mounted on the cross member 14 so as to be vertically swingable at one point via a rubber bush 32 whose axis extends in the vehicle front-rear direction. There is. Further, the upper arm 5 has a pair of bifurcated portions 5a, 5a that are bifurcated from the middle portion thereof to the outer end side (that is, the joint end side with the joint member 21), and between the both branched portions 5a, 5a. The damper device 6 is connected to the lower end of the damper device 6 while sandwiching the damper device 6, and is also connected to the connecting member 21 at the tips of the two branch portions 5a and 5a.

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

At the connecting portion between the connecting member 21 and the outer end of the upper arm 5 (specifically, the tip of each branching portion 5a), the second boss portion 21e of the connecting member 21 is provided as shown in FIG. A front-rear shaft 39 penetrating in the vehicle front-rear direction is provided, and ends of the front-rear shaft 39 are connected to the ends of the branch portions 5a of the upper arm 5 via rubber bushes 33, respectively. A sleeve member 40 is fitted on the outer periphery of the front-rear shaft 39 in a state of being sandwiched between both branch portions 5a of the upper arm 5. The sleeve member 4
On the outer peripheral surface of 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 at the rear side. A rear conical surface 40c that gradually expands in diameter as it faces is formed, and the second boss portion 21e of the connecting member 21 is rotatably fitted to this outer peripheral surface via a bush 41 made of resin. There is. The inner peripheral surface of the second boss portion 21e has a cylindrical surface 40a of the sleeve member 40 and a front conical surface 40.
b, the front conical surface 21g, and the rear conical surface 2 which face the rear conical surface 40c and the rear conical surface 40c at a predetermined distance.
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 to some extent by elastic deformation of the rubber bush 33. ing.

At the connecting portion between the lower end portion of the damper device 6 and the intermediate portion of the upper arm 5 (base end side of each branch portion 5a), the lower end portion of the damper device 6 is also shown in detail in FIG. On the bracket 38 attached to the upper portion, seat portions 38a, 38a having screw holes are formed so as to face the inner surfaces of the respective branch portions 5a of the upper arm 5, and the rotary bearings are provided at the respective branch portions 5a of the upper arm 5. 42 are provided. Then, from the side of each branch portion 5a of the upper arm 5, a fastening bolt 43 as a front and rear shaft is provided.
Through the rotary bearing 42 and the seat portion 38a.
The damper device 6 and the upper arm 5 are rotatably connected to each other around the axis of the fastening bolt 43 by being screwed and fastened to the screw hole.

The rubber bush 33 at the tip of the branched portion 5a of the upper arm 5 is, as shown in FIG.
The outer cylinder 33a fixed to the tip of the a, the inner cylinder 33b arranged concentrically with the outer cylinder 33a and having the front-rear shaft 39 inserted therein, and the outer cylinder 33a and the inner cylinder 33b. And an intermediate cylinder 33c arranged concentrically with the rubber 3 filled between the three cylinders 33a to 33c.
It consists of 3d and 33d. Although not shown, the rubber bushes 15, 17, 32 other than the rubber bush 33 are basically the same as the rubber bush 33, but some of them have an intermediate cylinder and some do not.

Next, the operation and effect of the above embodiment will be described. When the wheel 2 receives the steering force from the tie rod 20 via the knuckle member 1 and is steered to the left or right, the lower end side of the knuckle member 1 will be described. That is, the instantaneous rotation center point on the side of the lower arm 4 is the two link members 1 forming the lower arm 4.
It is the intersection O1 between the axes of 1 and 12. Further, the instantaneous rotation center point on the upper end side of the knuckle member 1 is
Rotates about an up-and-down shaft 23 that is a connecting shaft with the connecting member 21, and a structure composed of the damper device 6 and the upper arm 5 is connected to the vehicle body connecting point (center point of the rubber mount 36) of the upper end of the damper device 6 and the upper arm. Since it is rotationally displaced about a straight line L1 connecting the vehicle body connection point 5 (the center point of the rubber bush 32), the axis extension line L of the vertical shaft 23 is
This is the intersection O2 of 2 and the straight line L1. Therefore, the virtual kingpin axis is the straight line L3 passing through the two intersections O1 and O2.
However, the virtual kingpin axis L3 comes closer to the widthwise centerline L4 side of the wheel 2 and rises substantially vertically, and on the rotation centerline L5 of the wheel 2 than the widthwise centerline L4 of the wheel 2. The suspension performance slightly approaches the inner side of the vehicle body and approaches the ideal vehicle passing slightly outside the vehicle body from the widthwise center line L4 of the wheel 2 so that the grounding surface of the wheel 2 has a slight negative kingpin offset (-Δ). Can be improved.

Further, at the time of bump rebound of the wheel 2, the lower arm 4 and the upper arm 5 are respectively connected to the vehicle body (center points of the rubber bushes 15, 17, 32).
And swings up and down around the center point, and the wheel support member 1 or the wheel 2 performs a bump rebound operation up and down. At this time, the camber change characteristic of the wheel 2 is such that 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, so that the suspension device is more than the strut suspension device and the double wishbone suspension device. Can be set to the same level as. Further, since the damper device 6 is connected to the intermediate portion of the upper arm 5, it is necessary to secure a large vertical displacement amount (so-called suspension stroke) at the time of bump rebound of the wheel 2 in comparison with the expansion and contraction amount of the damper device 6. You can also

Moreover, since the lower end of the damper device 6 is connected to the intermediate portion of the upper arm 5 and does not extend downward near the rotation center line L5 of the wheel 2, the damper device 6 and the drive shaft interfere with each other. There is no such thing. Therefore, it is not necessary to adopt a special structure for avoiding this interference, and it is possible to simplify the structure, reduce the size and weight of the device, and the like.

Furthermore, since the number of connecting points of the upper arm 5 to the vehicle body is only one, the degree of freedom in layout can be increased accordingly.

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

In the above embodiment, the connecting portion between the lower end portion of the damper device 6 and the intermediate portion of the upper arm 5 is
The bracket 38 attached to the lower end of the damper device 6
The seat portions 38a, 38a having screw holes, and the rotary bearings 42 are provided on the respective branch portions 5a of the upper arm 5, and the fastening bolts 43 are attached from the side of the respective branch portions 5a of the upper arm 5 to the rotary bearings. Although it is configured such that the bracket 38 is penetrated through and screwed into the screw hole of the seat portion 38a, the present invention replaces the connecting structure with the bracket 38 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 relatively rotatably around the front-rear axis by a front-rear axis that penetrates through and extends to the other branch portion 5a of the upper arm 5.

Further, in the above embodiment, the present invention is applied to FF
Although the case where the invention is applied to the suspension device for the front wheels of the model vehicle has been described, the invention is not limited to this and can be applied to the suspension device of various vehicles.

[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 employ a special structure for avoiding the interference. The size and weight of can be reduced. Moreover, since the number of connecting points of the upper arm to the vehicle body is only one, the degree of freedom in layout can be increased accordingly. Further, since the camber change characteristics can be set to the same level as the double wishbone type with the strut type or higher, the suspension performance can be improved.

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

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

[Brief description of drawings]

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

FIG. 2 is a partially cutaway front view of the same as seen from the front of the vehicle body.

FIG. 3 is a plan view of the same.

FIG. 4 is a cross-sectional view showing a connecting structure of a knuckle member and a connecting member.

FIG. 5 is a cross-sectional view showing a connecting structure of an upper arm, a connecting member, and a damper device.

FIG. 6 is a cross-sectional view showing a modified example of the connecting structure of the knuckle member and the connecting member.

[Explanation of symbols]

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

Claims (3)

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