JPH0741859B2 - Vehicle suspension - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention comprises a suspension arm swingably attached to a vehicle body frame, and a cushion unit disposed between the arm and the frame. The present invention relates to a suspension device suitable for a saddle type vehicle, and more particularly to downsizing of a body frame and securing of an arm length of a suspension arm.

[Conventional technology]

For example, a saddle-ride type vehicle for traveling on rough ground forms a vehicle body frame by connecting a pair of left and right cradle-type side frames with a cross pipe, and front and rear wheels with wide ultra-low pressure tires at the front and rear portions of the vehicle body frame. It is configured by mounting the rear wheels. Then, as a suspension device that suspends and supports these wheels, conventionally, a suspension arm including an upper arm and a lower arm is swingably attached to a side frame,
There is a so-called double wishbone type in which a cushion unit is arranged between the arm and the frame and a knuckle bracket is attached between the tip ends of the upper and lower arms. In this suspension device, the lower arm is generally pivotally supported on the upper surface or the lower surface of the lower side portion of the side frame via a pivot bracket in order to make the arm length as long as possible.

[Problems to be solved by the invention]

When the suspension arm is pivotally supported by the lower surface of the lower side portion of the side frame, the distance between the pivotally attached portion and the road surface, that is, the so-called load clearance, is narrowed accordingly, and the pivotally attached portion is likely to be damaged especially when traveling on rough ground. There's a problem. On the other hand, when pivotally supported on the upper surface, the load clearance increases, but the front pivot bracket is placed at the front inner corner of the side frame, and the body frame projects forward accordingly. There is a problem that the frame length becomes long, and further, when the vehicle body swings up and down during traveling, there is a problem that the tip portion of the side frame easily comes into contact with the road surface.

Furthermore, when the pivot bracket is arranged on the outer surface of the side frame, there is a problem that the arm length of the suspension arm is shortened in the same vehicle width.

The present invention has been made to solve such conventional problems, and an object of the present invention is to provide a suspension device for a vehicle, which can make the frame compact, ensure the load clearance, and increase the arm length. I am trying.

[Means for solving problems]

According to the present invention, in a vehicle suspension system, the lower side portions of the left and right side frames are composed of horizontal portions and inclined portions that incline upward from the horizontal portions, and the front and rear base portions of the suspension arms are seen in plan view. The first and second pivot brackets are arranged so as to overlap the inclined portion and the horizontal portion, and the first pivot bracket is attached to the lower surface of the inclined portion, and the second pivot bracket is attached to the horizontal portion. And the left and right side frames are connected by the first and second pivot brackets.

[Action]

In the vehicle suspension system according to the present invention, a part of the lower side portion of the side frame is formed in an inclined shape that rises upward, and the first pivot bracket is formed on the lower surface of this inclined portion. It is not necessary to project the frame forward in order to secure the bracket mounting space, and the body frame is shortened by that amount, and is made compact. In this case, the first pivot bracket is formed on the lower surface of the frame, but since it is formed on the lower surface in the middle of the inclined portion, that is, at a position higher than the horizontal portion, the position of the first pivot bracket becomes low. Therefore, the road clearance can be secured, and if the vehicle width is the same, the arm length of the suspension arm can be increased by the amount that the axial fulcrum of the suspension arm is located inward in the vehicle width direction, and the suspension stroke can be increased.

Furthermore, since the left and right side frames are connected by the first and second pivot brackets, the rigidity of the side frames can be improved.

〔Example〕

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

1 to 5 are views for explaining a vehicle suspension system according to an embodiment of the present invention, and the present embodiment is an example applied to a front wheel suspension system of a saddle riding type vehicle for running on rough terrain. In the figure, reference numeral 1 denotes a steel pipe body frame, which is formed by connecting a pair of left and right side frames 2 with a cross pipe 3 and connecting a seat rail 4 to a rear portion thereof. A front bumper 5, a front fender 19, and a headlight 20 are provided at a front portion of the vehicle body frame 1, and a rear bumper 6 and a rear fender 18 are provided at a rear portion thereof. Then, a fuel tank having a tank cover 16a and a saddle type seat 17 are mounted. An engine 8 coupled to the crankcase 7 is mounted substantially in the center of the body frame 1, and rear wheels 14 with wide ultra-low pressure tires are mounted to the rear left and right through a rear arm 13. A rear wheel suspension device 12 is arranged between the rear arm 13 and the vehicle body frame 1.

Further, front wheels 11 with wide ultra-low pressure tires are also mounted on the left and right front portions of the vehicle body frame 1 via a double wishbone type front wheel suspension device 22. This front wheel suspension
Reference numeral 22 denotes an upper arm 23 and a lower arm 24 which are suspension arms, a knuckle bracket 25, a ball joint 26 connecting them, and a cushion unit 27 arranged between the lower arm 24 and the side frame 2. The front wheel 11 is rotatably mounted on the axle 25a integrally formed with the knuckle bracket 25.

The left and right side frames 2 are of a cradle shape, and the lower side thereof is a horizontal portion 2a extending in the horizontal direction,
Following this, there is an inclined portion 2b that inclines upward toward the front, a reinforcing pipe 2c is disposed between the horizontal portion 2a and the upper side portion, and the reinforcing pipe 2c and the tip of the inclined portion 2b are They are connected by a horizontally extending support pipe 2d. An upper front pivot bracket 28a and an upper rear pivot bracket 28b are fixed to the lower surface of the support pipe 2d at a predetermined interval, and the lower surface of the inclined portion 2b and the upper surface of the horizontal portion 2a have first pivots respectively. The lower front pivot bracket 29a, which is a mounting bracket, and the lower rear pivot bracket 29b, which is a second pivot bracket, are fixed so that both brackets 29a, 29b have substantially the same height and are horizontal. It is located higher than 2a. Also,
The suspension arm shaft support portions of both brackets 29a and 29b overlap the inclined portion 2b and the horizontal portion 2a in plan view (see FIG. 4). Then, the base portion 23a of the upper arm 23 is pivotally supported by the upper pivot brackets 28a and 28b, and the base portion 2 of the lower arm 24 is supported by the lower pivot brackets 29a and 29b.
4a is pivoted and both brackets 29a, 29 are
Since the shaft support portion of b overlaps with the inclined portion 2b and the horizontal portion 2a, the base portions 24a and 24a of the suspension arm 24 also have the inclined portion 2b,
It overlaps with the horizontal portion 2a. As a result, the bases (shaft fulcrums) 24a, 24a of the suspension arm 24 are located on the inner side in the vehicle width direction, and if the vehicle width is the same, the arm becomes longer and the suspension stroke can be increased.

Also, the first and second pivot brackets 29a, 29b connect the left and right side frames 2, 2 so that the rigidity of the side frames 2, 2 is improved.

The front bumper 5 is arranged in front of the left and right side frames 2 in the vehicle width direction.
Are horizontally extended in the vehicle width direction, and the support portions 5b fixed to the left and right lower surfaces of the bumper body 5a are the lower front pivot brackets.
It extends downward so as to cover the front of 29a, is bolted and fixed to the bracket 29a, and the upper portion of the support portion 5b is fixed to the vehicle body frame 1 by a connecting member 5c.

Next, the function and effect of this embodiment will be described.

As described above, in the conventional front wheel suspension device, when the lower pivot bracket for supporting the base portion of the lower arm is formed on the upper surface of the lower side portion of the side frame 2, the side frame 2 must be projected forward. Not obtained (see the dashed line in Fig. 1), the frame length becomes long, and there is a problem that the frame easily comes into contact with the road surface when the vehicle body vertically swings, and if it is formed on the lower surface, the load clearance becomes narrower. was there. On the other hand, in the present embodiment, the front portion of the lower side portion of the side frame 2 is an inclined portion 2b that rises upward,
Since the front pivot bracket 29a is fixed to the lower surface of the inclined portion 2b, the same height as that fixed to the upper surface while being fixed to the lower surface can be obtained, and a wide load clearance can be secured. Further, in this case, the front part of the side frame 2 does not project, the frame length can be shortened to make the frame compact, and the front part of the side frame 2 may contact the road surface due to the vertical swing of the vehicle body. Absent.

Further, in the past, when a multi-piece bracket was formed on the lower surface of the frame, there was a problem that the pivotal contact portion was easily damaged by contact with the road surface, but in the present embodiment, the lower front pivotal attachment portion 29a is horizontally leveled. Part 2a
The front bumper 5 is formed on the inclined portion 2b at a higher position and
Since it is covered with the supporting portion 5b, the problem of damage can be prevented.

It should be noted that in the above-described embodiment, the suspension arms are upper and lower 2
Although the description has been given of the suspension system for the front wheels, which is a daul wishbone type consisting of two arms, the present invention can be applied not only to a suspension system having one suspension arm but also to a suspension system for the rear wheels. Any suspension device can be applied as long as it has a suspension arm pivotably attached to it.

〔The invention's effect〕

As described above, according to the vehicle suspension device of the present invention,
The lower side of the side frame is composed of a horizontal portion and an inclined portion, and the lower surface of the inclined portion and the upper surface of the horizontal portion are respectively provided with first and second portions.
Since the base of the suspension arm is pivotally supported by the pivoting bracket so as to overlap the inclined portion and the horizontal portion in plan view, there is an effect that the frame length can be shortened while ensuring the load clearance, and the body frame can be made compact. Further, when the vehicle width is the same, the suspension stroke can be increased by increasing the arm length of the suspension arm. Furthermore, since the left and right side frames are connected by the first and second pivot brackets, the frame rigidity can be improved.

[Brief description of drawings]

1 to 5 are views for explaining a front wheel suspension system of a vehicle according to an embodiment of the present invention. FIG. 1 is a side view of a vehicle body frame thereof, and FIG. 2 is a side view of a suspension arm pivotal support portion thereof. 3 and 4 are a front view of the front wheel suspension system, FIG. 4 is a plan view of a lower arm portion thereof, and FIG. 5 is a side view of a saddle-ride type vehicle to which the device of the above embodiment is applied. In the figure, 1 is a body frame, 2 is a side frame,
2a is a horizontal part, 2b is an inclined part, 3 is a cross pipe, 11 is a front wheel, 22 is a front wheel suspension device, 24 is a suspension arm, and 24 is a suspension arm.
a is a base portion, 27 is a cushion unit, 29a and 29b are front and rear pivot brackets (first and second pivot brackets).

Claims (1)

[Claims] 1. A body frame is constructed by connecting a pair of left and right side frames with a cross pipe, and left and right suspension arms are vertically swingably attached to the left and right side frames, , A cushion unit is arranged between the right suspension arm and the vehicle body frame, and the left and right suspension arms have a left end at the tip end,
In a vehicle suspension system in which right wheels are mounted, the lower side portions of the left and right side frames are configured to include a horizontal portion that extends substantially horizontally, and an inclined portion that inclines upward following the horizontal portion, The first and second front and rear bases of the suspension arm are arranged so as to overlap the inclined and horizontal portions in plan view.
The first pivot bracket is pivotally supported by the second pivot bracket, the first pivot bracket is formed on the lower surface of the inclined portion, and the second pivot bracket is formed on the upper surface of the horizontal portion.
A vehicle suspension characterized in that the left and right side frames are connected and fixed by a pivot bracket.