JPS6322715A - Double-link type suspension device - Google Patents

Abstract

PURPOSE:To improve the degree of freedom for designing and make a device compact by pivotally supporting a shock absorber with a knuckle pivotally supported by a vehicle body via a lower arm and connecting one end of an extension member connected to the shock absorber at the other end to an upper arm. CONSTITUTION:The upper section 3a of a knuckle 3 supporting a wheel 1 is pivotally supported by the lower end of a tube 4a of a shock absorber 4 via a bracket 7 and upper and lower ball joints 8, 9, and the upper end of the shock absorber 4 is supported by a vehicle body 5. One end of a lower arm 11 connected to the vehicle body 5 at the other end is connected to the lower section 3b of the knuckle 3 via a ball joint 12. A king pin axis 13 is formed by passing the ball joints 8, 9, 12. In addition, one end of an upper arm 14a connected to the vehicle body 5 at the other end is connected to the tip of an extension member 14b, and the base end of the extension member 14b is fixed to the upper section of the tube 4a with a bolt 14c.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a double link suspension device.

[Conventional technology]

As a conventional double link type suspension device, there is one described, for example, in Japanese Patent Laid-Open No. 59-96007. That is, the suspension device described in the publication extends the upper part of the knuckle to above the wheel, and interposes an upper arm between the upper end and the vehicle body.
A lower arm is interposed between the lower part of the knuckle and the car body,
Furthermore, the lower end of the shock absorber is supported by the lower arm via a bifurcated fork member while avoiding interference with the drive shaft.

[Problem that the invention seeks to solve]

By the way, the upper arm of the double link suspension, as well as the lower arm, cannot be made too short and must be kept at a predetermined length in order to suitably set the suspension geometry.

Therefore, when considering the above-mentioned conventional technology, since the inner end of the upper arm is supported by the vehicle body and the upper end of the knuckle is connected to the outer end, the upper arm cannot be shortened for the above reason. Correspondingly, the wheel house has expanded towards the engine room side. Further, the shock absorber is arranged inside the knuckle so that the upper part of the knuckle extends above the wheel and is parallel to this.

For these two reasons, the conventional technology has a problem in that the width of the wheel house becomes large, and as a result, the width of the engine room is forced to become small. In particular, in the above-mentioned conventional technology, the upper part of the knuckle and the shock absorber are arranged parallel to each other, but since one knuckle turns together with the wheel during steering, care must be taken not to interfere with the shock absorber during this turning. A sufficient gap is required between the two.

Therefore, in the conventional technology, the width of the wheel house is increased in this sense as well. Furthermore, in the case of the conventional example, the upward extension of the knuckle also rotates with the wheel during steering, so the knuckle and upper arm are connected by a ball joint with a large height. However, there is also the problem that the height of the wheel house must be increased accordingly. Additionally, as the upper arm becomes longer, the connection between the outer end and the knuckle moves outward, which reduces the inclination of the kingpin axis and makes the scrub more positive, reducing steering stability when braking the vehicle. On the other hand, if the upper arm is shortened in an attempt to reduce the width of the wheel house, the amount of change in the camber angle due to the vertical movement of the wheel increases, resulting in a reduction in steering stability.

Furthermore, in the conventional technology, since the lower end of the shock absorber is supported by the lower arm, the lower arm needs to have high rigidity against downward bending input, which increases the weight of the lower arm and reduces the shock absorber. Another problem is that the rigidity of the rubber pushers at the connecting portions of the absorbers and the like must also be increased.

This invention was made by focusing on the problems of the prior art, and by separating the elements of setting the kingpin axis and setting the camber angle, etc., it is possible to freely set the outer end position of the upper arm. By increasing the speed and setting the wheel alignment appropriately, and also being able to independently set the kingpin axis, the width of the wheel house is made as narrow as possible and the width of the engine room etc. inside it is expanded. At the same time, the weight of the lower arm is reduced by preventing bending force from being applied to the middle of the lower arm.
The aim is to further reduce costs and increase flexibility in brake piping, etc.

[Means for solving problems]

In this invention, the lower part of the knuckle that supports the wheel and the vehicle body side are swingably connected by a lower arm, and the lower end of the shock absorber is connected to the upper part of the knuckle, passing through the connecting part between the knuckle and the lower arm. The joint between the knuckle and the shock absorber, which is rotatably connected around the wire as the center of rotation.

A kingpin shaft is constructed that passes through both joints between the knuckle and the lower arm, and one end of the extension member is attached to the tube of the shock absorber, and the other end of the extension member is swingable to the upper arm. It becomes connected.

[Effect]

Since the upwardly extending portion of the upper part of the knuckle is also used as a shock absorber, the only members that extend in the vertical direction inside the wheel are the upper part of the knuckle and the shock absorber that is continuous therewith.

The kingpin axis is a line that passes through both the joints between the knuckle and the shock absorber and the joint between the knuckle and the lower arm, and the kingpin shaft is unrelated to the upper arm, so the upper arm and the shock absorber tube are connected to each other. The space between the two parts could be swingably connected by an extension member. For this reason, it is possible to reduce the required width of the tire house while ensuring that the upper arm has sufficient length to suitably set the suspension geometry, and the king pin axis can also be suitably set regardless of the upper arm. can.

〔Example〕

FIG. 1 shows a first embodiment of the present invention.

This embodiment is a Wishbone type front suspension device, in which 1 is a wheel, 2 is a brake disc, and 3 is a knuckle. The knuckle 3 rotatably supports the axle 1, and its upper part 3a is rotatably connected to the lower end of a shock absorber 4 forming a suspension strut, and the upper end of the shock absorber 4 is supported on the vehicle body 5 via a mount rubber 6. be done.

The lower end of the tube 4a of the shock absorber 4 is connected to the upper part 3a of the knuckle 3 via the bracket 7 and upper and lower ball joints 8.9, and one end is connected to the lower part 3b of the knuckle 3 via a rubber bush 10. The other end of the lower arm 1) connected to the vehicle body 5 is connected to the ball joint 1.
2, ball joints 8, 9.12
A king pin shaft 13 is formed through it. A sufficient gap is ensured between the ball joint 12 and the brake disc 2.

An upper arm 14a is installed above the wheel 1 from the vehicle body 5. The upper arm 14a has a rubber bush 1 attached to the vehicle body 5.
5, and the other end is connected to the rubber bush 1.
6 to the tip of an extension bracket (extension member) 14b so as to be swingable in the vertical direction. The base end of the extension bracket 14b is fixed to the upper part of the tube 4a of the shock absorber 4 with a bolt 14c, so that the tube 4a is supported by the vehicle body 5 via the extension bracket 14b and the upper arm 14a. In this embodiment, the coil spring 4b is wound across the extension bracket 14b, and at the position where the extension bracket 14b passes, the pitch of the coil spring 4b is increased to prevent the upper arm 14a from moving up and down due to the up and down movement of the wheel 1. This is to prevent the coil spring 4b and the extension bracket 14b from interfering with each other even during swinging and expansion and contraction of the coil spring 4b. Note that the upper arm 14a
Also when there is a risk of interference between the coil spring 4b and the coil spring 4b,
Of course, similar to the above, means for avoiding interference may be employed.

In the figure, 17 is an axle, 18 is a drive shaft, 19 is a constant velocity joint between them, and 20 is a tie rod of a steering linkage.

In this embodiment, the widthwise centerline 21 of the wheel 1 and the kingpin shaft 13 intersect above the ground contact surface 30 of the wheel l, and the intersection of the ground contact surface 30 and the kingpin shaft 13 is the intersection point of the wheel 1. The setting of the king pin axis 13 is determined by the positional relationship of the ball joints 8, 9, and 12, and the scrub is set to zero by aligning it with the center line 21 in the width direction of the ball joint. or as for setting it to zero as above,
There is no relation to the upper arm 14a and the extension bracket 14b. Therefore, the rubber bush 16 connecting the tip of the upper arm 14a and the extension bracket 14b can be arranged without being restricted by the kingpin shaft 13, so in this embodiment, it is arranged directly above the wheel 1 and moved toward the outside of the vehicle, so that it can be moved across the vehicle width. By overlapping in the direction, the connection point of the upper arm 14a on the vehicle body side is positioned close to the outside in the width direction of the vehicle while ensuring a length of the upper arm 14a that allows optimum wheel alignment. This is one of the reasons why it is possible to narrow the width of the tire wheel house and expand the width of the engine room and the like inside it. Since the rubber bush 16 is located directly above the wheel 1, the upper arm 14a
and the tube 4a of the shock absorber 4 are connected by an extension bracket 14b, and this upper arm 14
a and another lower arm 1) support inputs from the front, rear, left and right sides of the vehicle.

In addition, by disposing the shock absorber 4 between the upper part 3a of the knuckle 3 and the vehicle body 5, the tube 4a
Since the upper extension part of the knuckle 3 is now also used, the only members that extend vertically inside the wheel 1 in the wheel house are the shock absorber 4 and the coil spring 4b on its outer periphery. This also
Coupled with the position of the upper arm 14a, this is the reason why the width of the wheel house can be narrowed and the width of the engine room etc. inside thereof can be further widened.

The wheel 1 is steered together with the knuckle 3 by moving back and forth the tie rod 20 of the steering linkage, and at this time, the steering rotation of the knuckle 3 and the wheel 1 is performed around the king pin shaft 13, but even when the wheel 1 moves up and down, Since the kingpin shaft 13 includes ball joints 8, 9, and 12, rotation other than around the kingpin shaft 13 does not occur.

In addition, the tube 4a and extension bracket 14b of the shock absorber 4 behave as one with the unsprung portion, and the upper arm 14a and lower arm 1) allow for changes in camber and toe, similar to conventional wishbone suspensions. is determined.

At this time, the mount rubber 6 at the upper end of the shock absorber 4 receives a horizontal input from the shock absorber 4 due to the movement of the upper arm 14a and lower arm 1), but this input is designed to shear the mount rubber 6. In addition, since the internal stress and friction of the mount rubber 6 are kept low, the mount rubber 6
has low rigidity against horizontal input. Furthermore, since the shock absorber 4 and the coil spring 4b act on inputs in the vertical direction, the mount rubber 6 has high rigidity due to compression against inputs in the vertical direction. In this way, the vertical input is performed by the shock absorber 4 and the coil spring 4b.
Since the shock absorber 4 is supported by the upper part 3a of the knuckle 3, the lower arm 1) does not need to support input in the vertical direction. Therefore, a bifurcated fork member as in the conventional example is not connected to the lower arm 1). Therefore, since the space around the bracket 7 can be made wider, there is also the effect that the degree of freedom of the brake piping (not shown) is increased.

When the wheel 1 bounces and the knuckle 3 rises, the coil spring 4b is compressed and the tube 4a of the shock absorber 4 rises, moving the extension bracket 14b upward, and the upper arm 14a swings with the twisting of the rubber bush 16. Then, it rises as shown by the chain line in FIG. In this way, as the wheel 1 moves up and down, the upper arm 1
4a behaves similarly, so wheel 1 and upper arm 1
4a and the extension bracket) 14b will not interfere with each other.

FIG. 2 shows an example in which the bracket 7 supporting the shock absorber 4 and the upper part 3a of the knuckle 3 are connected via rolling bearings 8a, 9a instead of the ball joints 8, 9 in FIG. be. That is, the bracket 7 and the upper part 3a are pivotally connected by a shaft 7b, and a bearing 3a is provided between the bracket 7 and the upper part 3a.

9a, the center line of the shaft 7a and the bearings 8a, 9a is set as the kingpin shaft 13.

FIG. 3 is an explanatory plan view showing the positional relationship of the upper arm 14a and the extension bracket 14b with respect to the wheel 1, and an example where these are arranged as shown in FIG. 1 is shown by a solid line A. Further, an example in which the tip of the upper arm 14a is simply connected directly to the tube 4a of the shock absorber 4 is shown by chain lines B and C. This figure shows that if the entire tire house is bent by the upper arm 14a and extension bracket 14b as in this embodiment, the width of the tire house can be narrowed, and as shown by chain lines B and C, only the upper arm can be bent. A frame is passed between the car body 5 and the tube 4a,
It can be understood that the width of the tire house is smaller than when the upper arm is only the required length.

FIG. 4 shows a second embodiment of the present invention, in which a coil spring 4b is arranged outside the shock absorber 4.
As a means for fixing the extension bracket 14b to the tube 4a of the shock absorber 4, the proximal end of the extension bracket l-14b was made into a cylindrical shape, and this was fitted onto the tube 4a. Also, the upper part 3a of the knuckle 3 and the side
As a connection means for connecting the 7-quapsorber 4, the bracket 7 is rotatably connected to the upper part 3a by using a sliding bearing using a resin bush 8b.

In addition, the coil spring 4b through which the extension bracket 14b passes
As in the first embodiment, the pinch is increased in the portion shown in FIG. 1 to prevent interference between the two. The other configurations and operations are the same as those of the previous embodiment, so their explanation will be omitted.

〔Effect of the invention〕

As explained above, according to the present invention, the components of the kingpin shaft are not related to the upper arm and the shock absorber is installed at the upper part of the knuckle, so that the arrangement of the upper arm is not restricted to the kingpin shaft, and moreover, it is inside the wheel. The only members that extend vertically in the suspension system are a series of shock absorbers and knuckles, so compared to conventional double-link suspension systems, the width of the wheel house can be significantly narrowed while allowing freedom in wheel alignment. This made it possible to expand the width of the engine room, etc. inside.

Further, according to the present invention, since the shock absorber does not rotate during steering, the joint between the upper arm and the extension bracket can be made of a rubber bushing, and the height of this joint can be made smaller than when using a ball joint. Therefore, by lowering the height of the wheel house, it is also possible to lower the hood of the engine compartment. This increases the flexibility of piping and wiring of various hoses, 5 tubes, and harnesses, and since these movements are not large, interference with other parts is minimized, and the space required is small. There is also the effect that it is sufficient.

In addition, the tube of the shock absorber becomes a strength member and can be made lighter.

Furthermore, since the shock absorber is connected to the upper part of the knuckle, there is no need to make the upper part of the knuckle long, and since the lower part of the shock absorber is not supported by the lower arm, there is no need for a bifurcated fork. Also, since no vertical load is applied to the middle of the lower arm,
There is no longer a need to enlarge the cross section of the lower arm. For this reason, it is possible to simplify the structure and reduce the weight of each part inside the wheel, and it is also possible to reduce the rigidity of the bushing that supports the lower arm on the vehicle body.

Further, according to the present invention, the relative movement force in the longitudinal direction that occurs between the vehicle body and the wheels when the vehicle starts or brakes is input onto the extension line of the king pin shaft in the upper arm, so this input is applied to the upper arm. The position is closer to the vehicle body than if it were at the tip, and therefore the load on the vehicle body mounting portion of the upper arm due to the input is reduced. Therefore, it is possible to reduce the weight of the vehicle body attachment part and to make the joint smaller and softer. Being able to soften the joint has the effect of suppressing vibration transmission to the vehicle body and reducing muffled noise caused by this.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway front view showing a first embodiment of the present invention;
FIG. 2 is an explanatory view showing another example of the suspension strut attachment part, FIG. 3 is an explanatory plan view comparing the arrangement of the upper arm, and FIG. 4 is a partially cutaway front view of the second embodiment. ■...wheel, 3...knuckle, 3a...upper part, 3
b...Lower, 4...Shock absorber, 4a...
・Tube, 4b...Coil spring, 5...Car body, 6
...Mount rubber, 7...Bracket, 8,9.
... Ball joint, 8a, 9a... Bearing, 8b.
...Resin bushing, 10...Rubber bushing, 1)...
・Lower arm, 12...Ball joint, 13...
・King pin shaft, 14a... Upper arm, 14b・
...Extension bracket, 15.16...Rubber bushing. Patent Applicant Nissan Motor Co., Ltd. Agent Patent Attorney Tetsuya Mori Patent Attorney Yoshiaki Naito Agent Patent Attorney Tadashi Shimizu Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] (1) The lower part of the knuckle supporting the wheel and the vehicle body side are swingably connected by a lower arm, and the lower end of the shock absorber is attached to the upper part of the knuckle along a line passing through the joint between the knuckle and the lower arm. are connected to each other so as to be rotatable about the rotation center to form a king pin shaft that passes through both the joints between the knuckle and the shock absorber and the joint between the knuckle and the lower arm, and furthermore, an extension member is attached to the tube of the shock absorber. A double link type suspension device, characterized in that one end of the extension member is attached, and the other end of the extension member is swingably connected to an upper arm.