JPH0146354B2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a wheel suspension system.

(Prior Art) Front wheel suspension systems for vehicles, especially motorcycles, are generally divided into two types: a telescopic system with sliding inner and outer cylinders, and a link system, and each structure has its own features. Currently, the telescopic system, which has a linear trajectory of the axle and has a sufficient stroke, is the mainstream.

In some car models, leading type,
A link system with good operability, such as a trailing type, is used, but in this case the trajectory of the axle is arcuate,
The reality is that it is limited to specific car models because it does not have enough stroke.

British Patent No. 526116 discloses a parallelogram link type aircraft wheel suspension having two swing arms.

(Problems to be Solved by the Invention) However, in the parallelogram link type suspension system, the arms that support the wheels are arranged almost vertically, so when this is adopted for motorcycles and automobiles, This limits the ability to reduce the vehicle height, and it cannot be said to be the best in absorbing uneven road surfaces.

Therefore, the purpose of the present invention is to focus on a quadrilateral link type suspension system that has good operability in order to transmit force in the rotational direction basically in accordance with the mechanistic Skottstratzell theorem, and to improve the vehicle height. It is an object of the present invention to provide a wheel suspension device which contributes to reduction in the number of wheels and which also has excellent absorbency for uneven road surfaces.

(Means for Solving the Problems) In order to solve the above problems and achieve the objects, the present invention provides a wheel suspension system that includes an upper arm 31 supported by a vehicle body, and a lower arm 61 that pivotally supports a wheel 8 at one end. are connected by the two swinging arms 4 and 5, and a line segment _l3 connecting the axle 65 support point of the lower arm 61 and the support point 42 for the lower arm 61 of the swinging arm 4 that is closer to this is connected to the vehicle body. It is characterized by being arranged almost horizontally in the initial setting state where no load is applied.

More specifically, a line segment l5 connects each support point ₄₂ , 52 of the two swing arms 4, 5 to the lower arm 61 with respect to the line segment _l3 , which is arranged substantially horizontally.
Place it by bending it upward.

(Function) Especially in the initial setting state where no load is applied to the vehicle body, the line segment _l3 is arranged almost horizontally, that is, the front half 62 of the lower arm 61 is arranged almost horizontally, so that the vehicle height can be reduced. In addition, it has excellent absorbency on uneven road surfaces.

Then, the line segment _l5 is bent upward with respect to the line segment _l3 , that is, the rear half 63 of the lower arm 61
If it is formed so as to be inclined rearwardly, it is possible to prevent the lower arm rear half portion 63 from being hit by the ground.

(Example) Examples will be described below based on the accompanying drawings.

Fig. 1 is a side view of the motorcycle, and Fig. 2 is a perspective view showing the link structure of the front wheel suspension system.
A handle stem shaft (not shown) is rotatably inserted and supported in the head pipe 11, and a top bridge 35 and a bottom bridge 36 are fixed in the middle at the upper and lower ends of the handle stem shaft. A bar handle 2 is fixedly attached to the bar handle 2.

A pair of left and right upper arms 31, 31 are fixed at the upper portions of both ends of the top bridge 35 and the bottom bridge 36, so that the upper fork 3
is configured. Front and rear swinging arms 4 and 5 are respectively pivotally supported at pivot points 41 and 51 at the lower ends and middle portions of the left and right upper arms 31 forming this upper fork 3, and the lower ends of the swinging arms 4 and 5 are A lower arm 61 is pivotally supported at the intermediate portion and rear end at pivot points 42 and 52, respectively. An axle 65 is installed between the front ends of the left and right lower arms 61, and a connecting shaft 66 is installed between the rear ends, thereby forming the lower fork 6.

At the lower part of the front swing arm 4 and the middle part of the upper arm 31, there is a shock absorber 7 serving as a springing means.
That is, a spring 71 and a shock absorber 72 are mounted coaxially, and a wheel 8 serving as a front wheel is mounted on the intermediate portion of the axle 65.

The front wheel suspension system thus includes the upper fork 3, the front and rear swing arms 4 and 5, and the lower fork 6 to form a quadrilateral link in side view.

In the above, as shown in FIG. 3, the front and rear swing arms 4 and 5 are arranged so as to converge downward, that is, each pivot point 4 of the front swing arm 4 with respect to the upper arm 31 and the lower arm 61
1 and 42 and a line segment l ₂ that also connects the pivot points 51 and ₅₂ of the swinging arm 5 on the rear side intersect below. As a result, the intersection point 0 between the line segment l ₁ and the line segment l ₂ is located below the rear half portion 63 of the lower arm 61 .

Here, the front swinging arm 4 is formed shorter than the rear swinging arm 5, so the quadrilateral link has a substantially rhombic shape that is long in the vertical direction, and a shock absorber 7 is disposed in the longitudinal direction within this rhombic link. will be established.

Then, above the line segment _{l 3} connecting the axle 65 support point of the lower arm 61 and the pivot point 42 and the line segment l ₁
The bisector _l4 of the angle formed by
Further, the axle 65 is disposed within the angular range formed by the upper part of the line segment _l5 connecting the pivot points 42 and 52 and the lower part of the line segment _l1 .

In addition, when no load is applied to the vehicle body, the line segment l ₃ is arranged almost horizontally, that is, the front half 62 in front of the intermediate pivot point 42 of the lower arm 61 is arranged almost horizontally, and the initial setting is made. On the other hand,
The line segment l ₅ , that is, the rear half 6 of the lower arm 61
3 is formed by tilting upward at the rear.

Furthermore, both swing arms 4 and 5 and the lower arm 61 are arranged on the rear side of the upper arm 31, and the axis S of the steering stem shaft supported in the head pipe 11 is arranged so as to intersect with the quadrilateral link when viewed from the side. The arrangement is such that the axis S intersects the front and rear swing arms 4 and 5.

Further, the rear swing arm 5 is arranged substantially vertically.

According to the embodiment, since the front and rear swing arms 4 and 5 constituting the quadrilateral link in side view are arranged so as to converge downward, the moment of the front wheel suspension during the vertical stroke of the axle 65 as shown in FIG. center 0
This allows a sufficient stroke of the axle 65 to be obtained, and the wheel 6 can be adjusted based on the length of the swinging arms 4, 5, the angle of convergence, etc.
5 can be set arbitrarily.

Moreover, as in the embodiment, the bisector _l4 of the angle formed by the lower part of the line segment _l1 and the upper part of the line segment _l3 is arranged to be substantially perpendicular to the travel path L of the axle shaft 65, and the line If the axle 65 is placed within the angular range formed by the lower part _l1 and the upper part _l5 , a linear travel path L of the axle 65 can be obtained as shown in FIG.

In particular, in the initial setting state where no load is applied to the vehicle body, the line segment l ₃ , that is, the lower arm 61
Since the front half 62 of the vehicle is arranged substantially horizontally, the vehicle height can be reduced, and the arrangement structure is excellent in absorbing uneven road surfaces.

Furthermore, for line segment l ₃ , line segment l ₅ , that is, lower arm 6
1 by bending the rear half 63 upward,
This is also advantageous in terms of preventing ground hits on the lower arm rear half 63.

Incidentally, in the embodiment, the front wheel suspension system of a motorcycle has been described, but it goes without saying that the present invention is also applicable to automobiles and aircraft.

(Effects of the Invention) As described above, according to the present invention, it is possible to obtain a wheel suspension system that can reduce the vehicle height and also has excellent absorbency for uneven road surfaces.

[Brief explanation of drawings]

FIG. 1 is a side view of the motorcycle, FIG. 2 is a perspective view showing the link structure of the front wheel suspension, and FIG. 3 is a schematic side view showing the arrangement and operation thereof. In the drawings, 1 is a frame, 11 is a head pipe, 3 is an upper fork, 31 is an upper arm, 35, 36 are bridges, 4, 5 are swing arms, 41, 42, 51, 52 are pivot points, 6 is the lower fork, 61 is the lower arm, 65 is the axle,
66 is a connecting shaft, 7 is a shock absorber, 8 is a wheel, _l1 ... _l5 are line segments, 0 is a momentary center, L is a stroke path of the axle, and S is an axis of the handle stem shaft.

Claims (1)

[Scope of Claims] 1. An upper arm supported by the vehicle body and a lower arm with a wheel supported at one end are connected by two swing arms, and the axle support point of the lower arm and the swing arm near it are connected. A wheel suspension system characterized in that a line segment connecting a support point to a lower arm is arranged substantially horizontally in an initial setting state where no load is applied to the vehicle body. 2. The wheel suspension system according to claim 1, wherein the line segment connecting each support point of the two swing arms to the lower arm is bent upward with respect to the line segment which is arranged substantially horizontally.