JPH0444405Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a front suspension in a vehicle such as an automobile.

(Prior Art) As a conventional front suspension, one shown in FIG. 6, for example, is known. (“Nitsun Service Bulletin No. 440: Introduction of T11 series vehicles”)
(Published by Nissan Motor Co., Ltd. in June 1981; see pages 133 to 141) This conventional front suspension was installed between the transverse link gazette 100 (body side member) and the nutcle 101. The transverse link 102 (lower arm) and the lower ball joint (lower ball joint point) interposed in the knuckle attachment part of the transverse link 102.
LB'), a front pivot 103 (pivot point FP') and a rear pivot 1 at vehicle longitudinal positions, which are interposed in the vehicle body attachment part of the transverse link 102.
04 (pivot point RP').

In addition, in FIG. 6, W is a wheel, and 105 is a steering device.

(Problem to be solved by the invention) However, in such a conventional front suspension, the axis pl' connecting the front pivot 103 (pivot point FP') and the rear pivot 104 (pivot point RP') was parallel to the vehicle center axis CL, so when looking at the vertical movement locus of the lower ball joint point LB' during the bound stroke and rebound stroke from the side view, it shows a straight line locus as shown in Figure 3. ST
During the bound stroke (in the direction of arrow B), the amount of increase in the backward inclination angle θ of the strut is small, and during the rebound stroke (in the direction of arrow R), the amount of decrease in the backward inclination angle θ of the strut is large. Ta.

Therefore, during large braking during a bound stroke, the amount of nose dive in which the front portion of the vehicle lowers becomes large.

This is because the rearward inclination angle θ of the strut is small, so that the instantaneous center I' during a nose dive is located at the rear of the vehicle body P, as shown in Figure 4, and the moment span S' relative to the force that causes the nose dive is Depends on how long it gets.

In addition, both a bound stroke and a rebound stroke can occur due to road surface irregularities, etc., but the lifting force generated during high-speed driving causes the vehicle body to rise (high-speed lift), and during high-speed driving where the rebound stroke is the main force, the rear tilt of the strut Because the angle θ is small, as shown in Fig. The horizontal distance between the two cars had become shorter, and straight-line stability had deteriorated.

(Means for solving the problem) The present invention was made with the purpose of solving the above-mentioned problems, and in order to achieve this purpose, the present invention has a lower arm provided in the vehicle width direction between the vehicle body and the knuckle, a lower ball joint interposed in the knuckle attachment portion of the lower arm, and a lower ball joint interposed in the vehicle body attachment portion of the lower arm. In the front suspension, the front pivot is provided with a front pivot and a rear pivot at longitudinal positions of the vehicle, and the front pivot is disposed on the outer side of the vehicle than the rear pivot.

(Function) Therefore, in the front suspension of the present invention, as mentioned above, by locating the front pivot on the outer side of the vehicle than the rear pivot, the side view of the lower ball joint point during the bound stroke and rebound stroke is improved. The trajectory is an arcuate trajectory centered ahead of the lower ball joint point, and during the bound stroke, the amount of increase in the backward inclination angle of the strut can be increased, and during the rebound stroke, the amount of decrease in the backward inclination angle of the strut can be reduced. can do.

(Example) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In describing this embodiment, the front suspension of a FF vehicle (front engine, front drive vehicle) will be taken as an example.

First, the configuration of the embodiment shown in FIGS. 1 and 2 will be explained.

A shows a front suspension according to an embodiment, and its main components include a nut 1, a strut 2, a transverse link 3 (lower arm), a lower ball joint 4, a front pivot 5, and a rear pivot 6.

The above-mentioned knuckle 1 is installed via a bearing 9 on a front hub 8 that rotates together with a drive shaft 7, and this knuckle 1 includes a strut 2, a transverse link 3, and a steering tie rod (not shown). It is attached.

Note that a wheel W consisting of a wheel 10 and a tire 11 is fixed to the front hub 8.

The strut 2 is a member that is provided in the vertical direction between the vehicle body 12 and the knuckle 1 and supports the load in the vertical direction, and is a coaxially arranged shock absorber 1.
3 and a coil spring 14.

Incidentally, the side view arrangement of the strut 2 is slightly inclined backward.

The transverse link 3 is a member that is provided in the vehicle width direction between the vehicle body 12 and the nuticle 1, and supports loads in the vehicle width direction (vehicle lateral direction) and longitudinal direction, and mainly supports loads in the vehicle width direction. It is formed into a substantially L-shape by a portion that receives the load and a portion that mainly receives the load in the front-rear direction.

The lower ball joint 4 is interposed in the knuckle attachment portion of the transverse link 3.

The front pivot 5 and the rear pivot 6 are interposed in the vehicle body attachment portion of the transverse link 3, and the pivot points FP, 6 of both pivots 5, 6 are
It is rotatably mounted around the shaft pl that connects the RP.

The front pivot 5 has a cylindrical bracket part 3a formed with a rubber bush inserted on the transverse link 3 side, and is attached to the vehicle body side bracket 12a with a bolt 15 (shaft member) and a nut 16.

Further, the rear pivot 6 has a rod member 3b fixed to the transverse link 3 side, and is attached to a cylindrical bracket 12b fixed to the vehicle body 12 via a rubber bushing.

Here, the front pivot 5 in the embodiment is arranged on the outer side of the vehicle than the rear pivot 6, and the rear pivot 6 is located at a distance l from the vehicle center line CL.
, while the front pivot 5 is at a distance l
It is located at a position where distance l′ is added to .

In the example, UP is the upper mount point of the strut 2, LB is the lower ball joint point of the transverse link 3, FP is the front pivot point of the transverse link 3, and RP is the rear pivot point of the transverse link 3. Point.

Next, the operation of the embodiment will be explained.

First, looking at the side view trajectory of the lower ball joint point LB, we see that the axis pl connecting the front pivot point FP and the rear pivot point RP is not parallel to the vehicle center line CL, but expands toward the front of the vehicle. Since the axis is arranged, as shown in Fig. 3,
The side view trajectory of the lower ball joint point LB during the bound stroke (in the direction of arrow B) and during the rebound stroke (in the direction of arrow R) is an arcuate trajectory CT (more precisely, an ellipse) with the center forward of the lower ball joint point LB. part of the trajectory), and the lower ball joint point LB moves toward the front of the vehicle both during the bound stroke and during the rebound stroke.

(B) During a bound stroke During a bound stroke, when the upper mount point UP is taken as a fixed point, the lower ball joint point LB moves to the front of the vehicle, so the amount of increase in the rearward inclination angle θ of the strut 2 is smaller than before. and grow bigger.

Therefore, during braking with a large bound stroke, as shown in FIG. 4, the backward inclination angle θ of the strut 2 increases, so that the instantaneous center I of the vehicle body P changes from the instantaneous center I′ in the conventional case. Since it is located further forward and the moment span S relative to the force that causes the nose dive becomes shorter, the amount of nose dive can be reduced.

Incidentally, the instantaneous center I appears on a line perpendicular to the line K connecting the upper mount point UP and the lower ball joint point LB.

Further, the force that causes the nose dive is the reaction force received by the vehicle body via the suspension, which is the resultant force F of the braking force BF and the road reaction force RF.

(b) During the rebound stroke During the rebound stroke, when the upper mount point UP is taken as a fixed point, the lower ball joint point LB moves to the front of the vehicle, so the amount of decrease in the rearward inclination angle θ of the strut 2 is reduced compared to the conventional one. and becomes smaller.

Therefore, both a bound stroke and a rebound stroke can occur due to road surface irregularities, etc.
During high-speed driving, where the vehicle body rises due to the lifting force generated during high-speed driving (high-speed lift) and the rebound stroke is the main component, the decrease in the backward inclination angle θ of the struts 2 is small, as shown in Fig. 5. Then, the caster trail C of the predetermined distance is
This ensures better straight-line stability than before.

Although the embodiments of the present invention have been described above in detail with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention may be modified without departing from the gist of the present invention. included.

For example, the positions of the front pivot and the rear pivot in the vehicle width direction may be appropriately set in consideration of wheel alignment, desired suspension performance, and the like.

(Effects of the invention) As explained above, the front suspension of the invention has a structure that allows the lower ball joint point to move forward during the bound stroke and rebound stroke, so when braking It is possible to reduce the amount of nose dive and improve straight-line stability during high-speed driving.

[Brief explanation of drawings]

Fig. 1 is a plan view showing the front suspension of the embodiment of the present invention, Fig. 2 is a front view of the front suspension of the embodiment, and Fig. 3 is a lower side view of the front suspension of the embodiment. A diagram showing the trajectory of the ball joint point during a bound stroke and a rebound stroke. Figure 4 is an illustration of the action during braking. Figure 5 is an illustration of the action during high-speed driving. Figure 6 is a diagram of the conventional front suspension. FIG. A... Front suspension, 1... Knuckle, 2... Strut, 3... Transverse link (lower arm), 4... Lower ball joint, 5... Front pivot, 6... Rear pivot,
12...Car body.

Claims (1)

[Scope of utility model registration request] A strut provided in the vertical direction between the vehicle body and the knuckle, a lower arm provided in the vehicle width direction between the vehicle body and the knuckle, and a lower ball joint interposed in the knuckle mounting portion of the lower arm. a front pivot and a rear pivot at vehicle longitudinal positions, which are interposed in the vehicle body attachment portion of the lower arm;
What is claimed is: 1. A front suspension comprising: a front pivot disposed on the outer side of the vehicle than a rear pivot;