JP2635067B2 - Vehicle suspension - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a vehicle suspension device used for a suspension mechanism of an automobile, an attendant vehicle, or the like.

[Conventional technology]

A strut-type suspension device represented by a McPherson type uses a shock absorber as a part of a suspension link, and is frequently used for a front wheel, that is, a steering wheel. A rear-wheel MacPherson type called a Chapman type is also known.

A well-known MacPherson-type suspension device is a columnar oil damper or strut, a steel coil spring provided on an outer peripheral portion of the strut, and a lower portion provided below the strut and rotated vertically in conjunction with the strut. It consists of a lower arm. When the strut expands and contracts due to input from the road surface, oil flows into the damping force generating mechanism inside the strut, and the coil spring bends in accordance with the expansion and contraction of the strut. Relative motion is absorbed.

[Problems to be solved by the invention]

The above-mentioned coil springs are used in conventional strut type suspension devices, but it is difficult for the coil springs used in such applications to sufficiently reduce the contact height due to wire diameter and winding. is there. For this reason, as long as a traditional coil spring is used, it is difficult to make the vehicle height lower than before.

Although it is not a McPherson type,
A specially shaped FRP spring as disclosed in Japanese Patent No. 847 has also been proposed. The spring disclosed in the prior art is composed of a plate-like end of a horizontally elongated elliptical ring-shaped integral leaf a as shown in FIG. 8 and a vertically symmetrical leaf b and c as shown in FIG. The part e is fastened by a bolt f.

However, of the above-mentioned prior art, the integral leaf a shown in FIG. 8 has considerably higher stress than the central part of the leaf because both ends g, g are bent beams. In addition, the camber h is determined by the curvature of both ends g, g, and there is a limit in reducing the curvature of both ends g, g due to stress. Therefore, it is not possible to apply a load until the leaf a comes into close contact with the top and bottom. It is possible. Also, as shown in FIG. 9, when the plate end e is fastened by bolts f, the adhesion height can be reduced, but the stress at the plate end e increases as in the case of FIG. Moreover, the leaves b and c rub against each other at the plate edge e,
Since fine foreign matter is likely to enter the gap i between the leaves b and c, the wear of the leaves b and c may significantly progress.
There is a problem with durability.

Accordingly, an object of the present invention is to provide a vehicle suspension device that can reduce the contact height of a strut type and has excellent durability.

[Means for solving the problem]

In order to achieve the above object, a spring assembly used in the suspension device of the present invention includes an upper spring plate made of FRP molded into an upwardly convex curved shape, and a spring plate disposed below and below the spring plate. It comprises a lower spring plate made of FRP molded into a convex curved shape.The upper spring plate and the lower spring plate are rotatable in the up and down directions at both ends by pivot means such as hinges. It is characterized by being connected to.

[Action]

In the vehicle suspension having the above configuration, when the strut expands and contracts according to the magnitude of the load applied in the vertical direction, the upper spring plate and the lower spring plate bend in the vertical direction. At this time, the upper spring plate and the lower spring plate are freely rotated via pivotal means such as a hinge provided at the end of the plate. In addition, problems such as rubbing and entry of foreign matter between the spring plates are avoided. Further, even if the two spring plates bend until they come into close contact with each other, no excessive stress is generated at the plate end. The contact height of these spring plates is sufficiently lower than the contact height of the coil spring.

〔Example〕

Hereinafter, the first embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to the drawings. The strut 2 of the suspension device 1 shown in FIG. 1 has a cylindrical first portion 3 like a conventional oil damper, and a rod-like portion which can reciprocate in the axial direction with respect to the first portion 3. A second part 4. A damping force generating mechanism having an orifice is provided inside the strut 2, and a damping force is generated by the flow of oil generated when the strut 2 expands and contracts.

The first part 3 is provided with a hub carrier 6.
The hub (not shown) of the wheel 7 is fixed to the hub carrier 6. The lower end of the hub carrier 6 is rotatably supported by a lower arm 9 via a joint 8. A base end of the lower arm 9 is supported by a shaft 11 on a subframe 12 of the vehicle body so as to be rotatable in a vertical direction. The upper end of the second part 4 is supported by the frame 14 by the upper mount 13. 15 is a stopper rubber.

A bracket 18 is fixed to the first portion 3. An upper seat 19 is provided on the upper mount 13 located on the second part 4 side. Then, between the bracket 18 and the upper seat 19, a spring assembly 21 is provided.
Is provided. The spring assembly 21 is arranged at a position shifted toward the hub carrier 6 with respect to the axis of the strut 2 in order to prevent bending stress from acting on the strut 2.

As shown in FIG. 2, the spring assembly 21 includes an upper spring plate 22 made of FRP and an FRP disposed below the spring plate 22.
And a lower spring plate 23 made of aluminum. Note that at least one of the upper spring plate 22 and the lower spring plate 23 may be a laminated leaf spring in which a plurality of spring plates are stacked in the thickness direction.

The upper spring plate 22 is formed in an upwardly convex curved shape, and the lower spring plate 23 is formed in a downwardly convex curved shape. That is, the two spring plates 22 and 23 are substantially vertically symmetrical.
These FRP spring plates 22 and 23 are made by reinforcing a well-known matrix resin mainly with unidirectional continuous reinforcing fibers along the longitudinal direction of the spring plates 22 and 23. Moreover, each spring plate 22, 23 is
It is formed in a tapered shape such that the plate thickness gradually decreases from the center toward both ends. That is, it is a tapered leaf. In this case, it is preferable that the spring plates 22 and 23 have a tapered shape such that the stress in each of the longitudinal portions is equalized.

The upper spring plate 22 and the lower spring plate 23 are connected to each other at both ends by metal hinges 25 and 26 as an example of pivot means so as to be rotatable in the vertical direction. Each hinge 25, 26, as shown on behalf of one in FIG.
A pair of movable pieces 25a, 25b rotatable relative to each other about a shaft 28.
, Seat plates 29, 30 and tightening bolts 31 and nuts 32
Etc.

In the present embodiment, by attaching the movable pieces 25a, 25b such that the end faces 22a, 23a of the spring plates 22, 23 are located immediately above the hinge shaft 28, almost the linear portions of the movable pieces 25a, 25b are formed. The entire length 1 is brought into close contact with the spring plates 22 and 23. This prevents local bending stress from being generated in the movable pieces 25a and 25b, and improves the durability of the hinge 25. The other hinge 26 has the same configuration.

Elastic bodies 3 made of a material having rubber-like elasticity, such as an elastomer, are provided on the longitudinal center portions of the spring plates 22 and 23, respectively.
5,36 have been installed. Each of the spring plates 22, 23 is made of an elastic body 35, 36.
Through the bracket 18 and the upper sheet 19. As a means for fixing the hinges 25, 26 to the spring plates 22, 23, an adhesive may be used instead of a bolt, or a combination of fastening and bonding with a bolt may be used.

The design example of the spring assembly 21 is shown in Table 1 below. While the total plate thickness of the FRP spring assembly 21 of the present embodiment at the time of close contact is about 24 mm, the close contact height of the conventional steel coil spring is 77 mm.
Therefore, the contact height can be reduced to about one third of the conventional height.

In the suspension device 1 having the above configuration, when the hub carrier 6 moves up and down according to the magnitude of the input from the road surface, the first portion 3 and the second portion 4 of the strut 2 reciprocate up and down in conjunction with the movement. Move. Further, the lower arm 9 pivots in the vertical direction, and the upper spring plate 22 and the lower spring plate 23 bend in a direction in which they come into contact with and separate from each other. The vertical vibration of the hub carrier 6 is attenuated by the bending of the spring plates 22 and 23 and the damping action of the struts 2 in this manner.

When the upper spring plate 22 and the lower spring plate 23 bend in the vertical direction, the ends of the two plates freely rotate via the hinges 25 and 26, so that even if the spring plates 22 and 23 are repeatedly bent, There is no problem such that the members are rubbed against each other and worn, and foreign matter enters between the spring plates 22 and 23. The spring plates 22 and 23 made of FRP can be more flexed than the steel spring plates, and the plate ends are pivotally attached by hinges 25 and 26 so that the spring plates 22 and 23 can be freely rotated. , 23 can be flexed until they come into close contact with each other, so that no excessive stress is generated at the end of the plate, so the camber can be freely determined so that the spring plates 22, 23 come into close contact with each other. The degree of freedom of design is extremely large.

Moreover, in this embodiment, since the tapered leaves are used for the spring plates 22 and 23, when the spring plates 22 and 23 bend in the direction in which they are in close contact with each other, the spring plates 22 and 23 bend more flatly than when the equal-width, equal-thickness spring plate bends. Because of the close contact, the contact height can be further reduced as compared with a spring plate having the same width and the same thickness.

Incidentally, as shown in FIG. 4, a stopper rubber 38 may be attached to one of the spring plates 23 (or 22).
In this case, the stopper rubber 15 described in the above embodiment can be omitted.

The second embodiment of the present invention shown in FIGS. 5 to 7 is a suspension device 1 used for steering wheels such as front wheels. In this embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals as in the first embodiment, and the description is omitted.

Since the direction of the hub carrier 6 changes with the steering operation, the strut 2
Rotates around its axis. In this case, the spring assembly 21
If the spring rotates together with the strut 2, the space occupied by the spring assembly 21 becomes extremely large. For this reason,
It is necessary to take measures to prevent the spring assembly 21 from rotating even when the strut 2 rotates. For this reason, in this embodiment, the strut 2 and the spring assembly 21 are provided so as to be relatively rotatable. That is, as shown in FIG. 6, the upper part of the strut 2 is rotatably supported by the upper mount 13 via the bearing 40. As shown in FIG. 7, a ring-shaped bracket 41 extending along the circumferential direction is provided at an intermediate portion of the strut 2 in the vertical direction, and the bracket 41 is provided with a bearing 42 for supporting an axial load. A receiving seat 43 is provided. The receiving seat 43 is rotatable around the axis of the strut 2. A support for receiving the elastic body 36 is provided on the receiving seat 43
44 are provided.

According to the second embodiment having the above configuration, even when the strut 2 rotates around the axis during steering, the spring assembly 21 does not rotate because it is integrated with the upper mount 13. Therefore, the space occupied by the spring assembly 21 can be minimized.

〔The invention's effect〕

ADVANTAGE OF THE INVENTION According to this invention, since the contact height of a spring can be made small compared with the conventional strut type suspension using a coil spring, it is effective in reducing the size of the suspension mechanism part in the up-down direction. is there. In addition, even if FRP spring plates, which are relatively weak against wear, are used, they do not rub against each other or cause foreign matter to enter between the spring plates and cause wear, and have excellent durability. A suspension system is obtained.

[Brief description of the drawings]

1 to 3 show a first embodiment of the present invention.
FIG. 2 is a front view of the suspension device, FIG. 2 is a perspective view of the spring assembly, FIG. 3 is a side view showing a mounting portion of the hinge, FIG. 4 is a perspective view showing an example of mounting a stopper rubber, and FIGS. 7 shows a second embodiment of the present invention, FIG. 5 is a front view of a suspension, FIG. 6 is a cross-sectional view of the upper part of a strut, FIG. 7 is a cross-sectional view showing a bearing portion, and FIG. FIG. 9 is a perspective view of an FRP spring plate, and FIG. 9 is a perspective view of a part of the FRP spring plate showing still another conventional example. DESCRIPTION OF SYMBOLS 1 ... Suspension device, 2 ... Strut, 3 ... First part, 4 ... Second part, 9 ... Arm, 21 ... Spring assembly, 22 ... Upper spring plate, 23 ... Lower spring Board, 25,26 ……
Hinge (pivot means).

Claims (4)

(57) [Claims] 1. A strut having a first portion and a second portion that are relatively reciprocally movable in an axial direction, and an arm located below the strut and reciprocally movable up and down in conjunction with the strut. A suspension comprising a spring assembly provided between a first portion and a second portion of the strut, wherein the spring assembly comprises a top spring plate made of FRP formed into an upwardly convex curved shape. And an FRP lower spring plate which is disposed below the spring plate and is formed into a downwardly convex curved shape, and the upper spring plate and the lower spring plate are respectively provided at both ends. A suspension system for a vehicle, wherein the suspension system is pivotally connected to each other by a pivot means. 2. The vehicle suspension according to claim 1, wherein said spring plate is made by reinforcing a matrix resin with one-way continuous reinforcing fibers along a longitudinal direction of the spring plate. 3. The vehicle suspension according to claim 1, wherein said spring plate is formed in a tapered shape such that a plate thickness gradually decreases from a center side to both end sides of said spring plate. 4. The strut according to claim 1, wherein said strut is provided with a receiving seat which is rotatable relative to the axis of said strut, and said spring assembly is supported via said receiving seat. Suspension system for vehicles.