JPS63176709A - Rear suspension device - Google Patents

Abstract

PURPOSE:To promote the elimination of interference with a fuel tank and the improvement of driving stability, by specifically arranging a lower arm, having three connection end parts, and an assist link having two connection end parts, in the case of an independent type rear suspension device. CONSTITUTION:A lower arm 5 connects its rubber bush 8 with the front part of a wheel supporting knuckle 2 and rubber bushes 9, 10 with a car body 3. Here the rubber bushes 9, 10 are positioned in the rear of the car body from a center line 12 of a wheel 1, further the front side bush 9 is positioned in the vicinity of the center line 12 in accordance with the shape of a fuel tank 13. While the bush 8 is longitudinally soft set so as to perform the soft displacement to the longitudinally relative displacement of predetermined dimension between the knuckle 2 and the lower arm 5. By this constitution, interference with the fuel tank is eliminated, further driving stability improves by placing the wheel, when it inputs lateral force and longitudinal force by a brake, in a toe-in condition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an independent rear suspension device.

[Prior Art] As a conventional independent rear suspension device, there is one described, for example, in Japanese Utility Model Application Publication No. 57-163404. This rear suspension device includes: a first link to which the axle is fixed and which extends in the longitudinal direction; and a second link that connects the front end of the first link and the vehicle body side in the vehicle width direction.
A third link that connects the rear end of the first link and the vehicle body side in the vehicle width direction is connected to the vehicle body side by a quadrilateral link, and the middle of the first link and the vehicle body side are connected by a restraint link. This prevents the quadrilateral link from deforming.

[Problem that the invention seeks to solve]

However, according to such conventional technology, since the second link on the front side is connected to the vehicle body side in front of the wheel center line, the position of the gasoline tank, which is normally placed in front of the wheel center line, is different from the position of the gasoline tank. Due to interference, it is not possible to provide enough space for the gasoline tank.

In addition, when toe-in the wheels due to lateral force input when the vehicle turns, etc., the connecting portions at both ends of the second link on the front side (rubber bushings are usually used)
It is necessary to soften the connection part to effectively shorten the second link, but if the connection part is made soft in this way, sufficient toe rigidity during normal driving cannot be ensured, so there is a risk that steering stability will decrease. There is.

Furthermore, since this conventional technology uses quadrilateral links that are easily deformed, if the rubber at the end connecting portions of the restraining links to prevent deformation deteriorates, the restraining force of the restraining links decreases. As a result, the easily deformable quadrilateral link is excessively deformed by longitudinal force when the vehicle starts or brakes. In addition, in order to prevent the bounding from being obstructed by the action of the restraint link when the wheel bounces, the line connecting the vehicle body side connecting portion of each link and the line connecting the wheel support member side connecting portion need to be parallel. However, making them parallel like this reduces the degree of freedom for controlling the behavior of the wheels when bouncing.

This invention was made by focusing on the above-mentioned problems of the prior art. Normally, toe rigidity is maintained high, and depending on the lateral force, the wheels are directed toward toe-in, and the front link is used to direct the wheels toward toe-in. The purpose is to prevent space limitations.

[Means for solving problems]

The rear suspension device of the present invention has three connecting ends, and one end is connected to the wheel support member side and the other two ends are connected to the vehicle body side so that they can both swing vertically in the vehicle width direction. An extending lower arm, one end of which is vertically swingably connected to the wheel support member side behind the wheel support member side connection end of the lower arm, and the other end is connected to the lower arm behind the wheel support member side connection position. Equipped with an assist link,
The front joint end of the two vehicle body side joint ends of the lower arm is arranged near the wheel center line and the rear joint end is arranged behind the front joint end, and the wheel support member of the lower arm is provided. The side joint ends are set to be soft in the front and rear until a predetermined longitudinal relative displacement between the wheel support member side and the lower arm occurs.

[Operation] Front-rear and left-right directions (vehicle width direction) between the wheels and the vehicle body
The force is supported by the lower link and assist link. The force in the vertical direction is supported by springs or the like, which are outside the constituent elements of the present invention.

In addition, the front side of the lower arm's connecting end on the vehicle body side is located near the wheel center line, and the rear side is located further rearward than that. Since there is no interference with the fuel tank, the capacity of the fuel tank can be made sufficiently large.Secondly, due to the above-mentioned arrangement, the wheels become toe-in when a lateral force is input, resulting in excellent steering stability when the vehicle turns.

Furthermore, the joint end of the lower arm on the wheel support member side is set to be soft, and since the assist link rotates in the front and rear direction due to the front and back force between the wheel support member side and the vehicle body side, it is soft and stiff in the front and rear. Excellent blocking performance. Also, during braking, the wheel support member side of the lower arm as a whole tilts rearward and faces in the toe-out direction, but since the joint end of the lower arm on the wheel support member side is soft, the wheel moves rearward with respect to the lower arm, thereby providing assistance. When the wheel support member side joint end of the link also moves rearward, the assist link rotates rearward about the lower arm side joint end. When the assist link rotates in this way, the assist link is tilted so that the vehicle body side is toward the rear, and the connected end on the wheel support member side protrudes outward in the vehicle width direction, so the wheel is forced to move. Turn to toe-in.

As a result, the wheels become toe-in not only due to the lateral force as described above but also due to longitudinal force.

〔Example〕

Fig. 1.2 shows an embodiment of the present invention, and FR indicates the front of the vehicle body. Reference numeral 1 denotes a rear wheel, which is rotatably supported by a knuckle 2 serving as a wheel support member. A lower arm 5 is installed between the knuckle 2 and the vehicle body 3,
An assist link 4 is installed between the knuckle 2 and the lower arm 5.

The lower arm 5 includes three rubber bushes 8, 9, and 10 and is supported at three points. The front part of the knuckle 2 and the lower arm 5 are connected to each other via the rubber bushes 8 so as to be able to swing up and down. The lower arm 5 and the vehicle body 3 are supported so as to be able to swing up and down via two rubber bushes 9 and 10. The rubber bushing 8 is set to be soft in the front and rear, so that the wheel 1 and the lower arm 5 are easily displaced in the front and back. However, once this displacement reaches a predetermined value, a stopper (not shown) prevents further displacement. It has become. That is, it is set to be soft for longitudinal displacement within a predetermined value and hard for displacement beyond this value.

Reference numeral 3a shown in FIG. 2 is a bracket forming a part of the vehicle body 3, and both rubber bushes 9 and 10 on the vehicle body side are pivotally connected to this bracket. Reference numeral 11 denotes a line connecting both rubber bushes 9 and 10, and this line 11 is set at the rear so as to be inclined outward in the vehicle width direction in plan view and downward in side view.

The assist link 4 is provided with one rubber bush 6.7 at each end, and the rear part of the knuckle 2 and the assist link 4 are connected via the rubber bush 6.
The assist link 4 and the midway portion of the lower arm 5 are coupled to each other via. The shaft of the rubber bush 6.7 is oriented in the vertical direction, and the rubber bush 7 is positioned rearward of the rubber bush 6, so that the assist link 4 is inclined so that the inner side in the vehicle width direction is at the rear when viewed from above. .

Further, both rubber bushes 9 and 10 on the vehicle body side are located behind the center line 12 of the wheel 1 and do not interfere with the fuel tank 13 located in front of the center line 12. Furthermore, since the VAll connecting the rubber bushes 9 and 10 is slanted toward the rear, it does not interfere with the spare tire house 14 located behind the center line 12. Note that depending on conditions such as the shape and dimensions of the fuel knob 13, the rubber bush 9 on the front side of the vehicle body may be positioned on the center line 12 or slightly in front of the center line 12 without interfering with the fuel tank 13. do not have. Therefore, the rubber bushing 9 does not necessarily need to be located on the rear side of the center line 12, but can also be placed somewhat on the front side of the center line 12. This is the meaning of the present invention in which the rubber bush 9 is positioned near the center line 12 or later.

A strut 15 shown in FIG. 2 is installed between the knuckle 2 and the vehicle body 3 to support the force in the vertical direction. It can also be a bone type. Note that 16 is an exhaust pipe, 17 is a muffler for the exhaust pipe 16, and 18 is a side member forming a part of the vehicle body 3.

Thus, the force between the vehicle body 3 and the wheels 1 in the longitudinal direction and the vehicle width direction is directly supported by the lower arm 5 and also supported by the lower arm 5 via the assist link 4. Also, the vertical force is supported by the strut 15, but the strut 1
When an upper arm and a spring are used instead of 5, the support is provided by the spring. In this case, the forces in the longitudinal and vehicle width directions are also supported by the upper arm.

Here, since the rubber bushes 9 and 10 on the vehicle body side are both located behind the center line 12 of the vehicle width 1, when a lateral force acts on the vehicle width 1 when the vehicle turns, etc., the rubber bushes 6 to 10 on the vehicle body side
With the deformation of 10, the lower arm 5 tilts slightly forward of the vehicle body, so the wheels 1 become toe-in, improving steering stability. Further, since the rubber bushes 9 and 10 on the vehicle body side are arranged behind the center line 12 as described above, they do not interfere with the fuel tank 13. For this reason, fuel tank 1
It is also possible to secure a sufficient capacity of 3.

Note that even if the rubber bushing 9 is on the center line 12 or slightly forward of this, the vehicle body 3 due to both rubber bushings 9,1°
If the center position of the human force is on the rear side of the center line 12, toe-in occurs as described above.

Furthermore, with respect to the longitudinal force between the vehicle body 3 and the wheels 1, the rubber bush 8 is a soft comb up to a predetermined movement in the longitudinal direction, reducing harshness, and during braking, the lower arm 5 as a whole The wheel 3 side tilts rearward and faces in the toe-out direction, but since the rubber bushing 8 is soft, the wheel 3 moves rearward with respect to the lower arm 5, and as a result, the wheel side joint end of the assist link 4 (position of the rubber bushing 6) When the assist link 4 moves rearward, the assist link 4 rotates rearward around the rubber bush 7.

When the assist link 4 rotates in this way, the assist link 4 is tilted so that the rubber bushing 7 is on the rear side of the rubber bushing 6, so the position of the rubber bushing 6 at the wheel side joint end is outward in the vehicle width direction. Since it will stick out, force axle 3 toward toe-in. Thus, the wheels 3 become toe-in not only due to the lateral force as described above but also due to longitudinal force.

Furthermore, since the line 11 passing through the rubber bushings 9.10 is downward-sloping as described above, the rubber bushings 9.1
Since 0 is located below the spare tire house 14, this spare tire house 14 can also take up sufficient space.

Further, according to this embodiment, the rubber bushing 9 on the vehicle body side.
The plane angle of the line 11 connecting the wheels 10 and the plane angle of the line 19 connecting the rubber bushes 6.8 on the wheel side can be set individually, and the vertical inclination and length of the assist link 4 can be changed. Therefore, there is a large degree of freedom in setting the toe characteristics.

〔Effect of the invention〕

As explained above, according to the present invention, since the lower arm having three connecting ends and the assist link having two connecting ends are arranged as described above,
Firstly, there is no interference between the fuel tank located in front of the axle and the lower arm, so the capacity of the fuel tank can be made sufficiently large.Secondly, due to the above arrangement, lateral forces and braking The wheels are toe-in when the vehicle is under human power, resulting in excellent handling stability during vehicle turns and braking. Thirdly, the lower arm's wheel support member side joint is softened back and forth to a predetermined relative position, reducing harshness. It also has the effect of being highly effective in preventing the transmission of.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing an embodiment of the invention, and Fig. 2 is a plan view showing an embodiment of the invention.
FIG. 1...Wheel, 2...Knuckle, 3...Car body, 4...
...Assist link, 5...Lower arm, 6-10.
・Rubber bush (joint part), ll...Line connecting the rubber bushes on the vehicle body side, 12...Wheel center line, 13...Fuel tank, 14...Spare tire house

Claims (1)

[Claims] A lower arm which extends in the vehicle width direction and has three connecting ends, one end being connected to the wheel support member side and the other two ends being connected to the vehicle body side so as to be able to swing vertically; an assist link that is vertically swingably coupled to the wheel support member side behind the wheel support member side coupling end and whose other end is coupled to the lower arm on the rear side of the wheel support member side coupling position; The front joint end of the two vehicle body side joint ends of the lower arm is arranged near the wheel center line and the rear joint end is arranged behind the front joint end, and the wheel support member of the lower arm is provided. A rear suspension device characterized in that a side joint end is set to be soft in the front and rear until a predetermined length of front-to-back relative displacement between the wheel support member side and the lower arm.