JPS63287613A - Frp made suspension arm structure for vehicle - Google Patents

Abstract

PURPOSE:To easily form an arm structure and to promote the improvement of its durability, by forming an arm main unit, which arranges fibers in the lengthwise direction further forms both ends at a right angle with the lengthwise direction, by fiber reinforced plastic (FRP) while providing boss members to butt in both end faces and forming layers, impregnated with resin, in the periphery of both the boss members and the arm main unit in their lengthwise direction. CONSTITUTION:An arm main unit 10 is molded in a shape of almost squared pillar by fiber reinforced plastic (FRP) drawing fibers to be arranged in the lengthwise direction, forming both end parts 11, 11 into a face vertical with the lengthwise direction. While a boss 2 is formed by a squared pillar, having a side face 21 of the same shape to the end face 11 of the arm main unit 10, and a semi-circular part, and it provides a mounting hole 22 being surrounded by a shock absorbing member 24. And after the arm main unit 10 and the boss 2 are adhesively attached by an adhesive agent in their end faces 11, 21, a peripheral layer 3, arranging fibers in the lengthwise direction, is formed by filament winding forming method being fixed to upper and bottom surfaces of the arm main unit in its lengthwise direction. By this constitution, the improvement of durability can be promoted by easily performing forming and processing work.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an FRP suspension arm structure in which a suspension arm in a vehicle suspension system is made of FRP.

(Prior Art and Its Problems) Conventionally, attempts have been made to form structural parts of vehicles (particularly passenger cars) from plastic in order to reduce weight.

Regarding suspensions, it has been considered to form structural parts such as suspension arms from FRP.

FRP has stronger mechanical strength per unit weight than metal materials, and if a suspension arm is constructed from such a material.

The unsprung weight can be reduced, and suspension characteristics can be improved.

However, FRP has a so-called anisotropy in which the strength differs in the direction of stress, and when tensile and compressive stress is repeatedly applied to the suspension 7-me, fixing boss parts must be formed at both ends. Therefore, it was impossible to mold it into a medium-pure material and replace it with a metal material.

Therefore, as disclosed in Japanese Patent Application Laid-open No. 101415/1983 (
6), the arm body 10 is formed of FRP with the fiber direction as the longitudinal direction, and cylindrical boss members 2, 2 are attached to both ends, and the arm body 10 and the boss members 2, 2 are made of resin-impregnated fibers. 2 is wound in the longitudinal direction to form an outer peripheral layer 3 and integrated, and the suspension and arm l
There is something that consists of

With this configuration, the arm main body 10 will be able to withstand compressive stress.
The outer peripheral layer 3 resists tensile stress, and an effective suspension arm structure that can be replaced with a metal material can be obtained.

However, in the L structure, the arm body 10 and the boss member 2
The contact portion (i.e., the end face 1 of the arm body 10) is formed into an arc shape corresponding to the outer peripheral shape of the boss member 2, since it is necessary to distribute and equalize the applied pressure and prevent stress concentration. There must be.

Such arc-shaped forming is generally done by cutting with a plain cutter formed to a predetermined outer diameter (same diameter as the boss member) (even if the shape is approximated when forming the arm body) , cutting is necessary to obtain the specified accuracy).

In this case, the cutter lO is the fiber 1 of FRP as shown in Fig. 7.
This process is performed by cutting in a direction parallel to the direction of 0A, but in this type of processing (i.e., cutting with a cutter and forming it into the same shape as the cutter), the fiber fiL
The OA processing conditions differ depending on the position of the cutting edge of the cutter 10. ＃Tch, Sen,! There is a so-called upper cut portion where the cut is made at an acute angle to the direction of the fiber IA (towards the fiber direction), and a so-called down cut portion where the cut is made at an obtuse angle to the direction of the fiber IA (following the fiber direction).

As is well known, the fiber M (glass fiber or carbon fiber) of FRP has poor workability, and this causes the problem that the fiber becomes fluffy in the upper cut area, resulting in poor surface accuracy and frequent processing defects. be.

Further, the cutting edge diameter of the cutter IO changes due to wear, and the machining shape changes, and the relationship between the cutter feed rate and the depth of cut (1SIf) changes, resulting in poor machining accuracy.

Furthermore, if compressive force is applied during use.

As shown in FIG. 8, the direction of the pressure F applied from the boss member 2 to the arm body 10 is perpendicular to the end surface of the arm body lO. Since it has a circular arc shape, it acts to spread out the end of the arm body 10 near its side end, that is, the boss member 2
acts like a wedge), as a result, m of the arm body 10
There are also problems in that cracks occur in the direction parallel to the fiber direction (strength is poor in this direction) and durability is poor.

(Object of the Invention) In view of the above circumstances, an object of the present invention is to provide an FRP suspension arm structure for a vehicle that is easy to mold and process and has high durability.

(Structure of the Invention) Therefore, in the FRP suspension arm structure for a vehicle according to the present invention, the fiber direction of the FRP is aligned in the longitudinal direction, and both end faces in the longitudinal direction are set as planes perpendicular to the longitudinal direction of the arm body. At the same time, a boss member having a flat surface that comes into contact with the end face of the arm body is formed, and the boss member is brought into contact with both end faces of the arm body, and fibers impregnated with resin are applied to the arm body and the bushing members at both ends. It is constructed by forming an outer peripheral layer around the circumference in the longitudinal direction.

(Example of the invention) Next, an embodiment will be described based on one drawing.

FIG. 1 is a perspective view of an embodiment of the suspension arm structure of the present invention, and FIG. 2 is an exploded perspective view showing its configuration.

Figure 5 shows an example of the rear wheel suspension structure (strut type) of a front-wheel drive vehicle.

The suspension arm l constructed according to the present invention includes, for example, a link arm 52 that connects the cross member 50 and the knuckle 51, and a link arm 52 that connects the knuckle 51 and the chassis (
It can be used for the tension rod 53 etc. that connects the body).

The suspension arm 1 has bosses 2, 2 integrally formed on the outer peripheral layer 3 at both longitudinal ends of the arm body 10, and mounting holes 22 formed in the bosses 2, 2 at both ends.
It is configured to be attached at a predetermined position by @22.

The arm main body 10 is a hollow substantially rectangular prism shaped with a predetermined cross-sectional shape and a predetermined length, and is formed of FRP with the fiber direction aligned with the longitudinal direction. Further, both end portions 11ψ11 in the longitudinal direction are formed perpendicularly to the longitudinal direction with a predetermined planar accuracy.

The boss 2 is a so-called semicircular prism having a side surface having the same shape as the end 11 of the arm body 10, and the side surface opposite to the side surface is formed into a semicircular shape with the height as the diameter. A side surface having the same shape as the end 11 of lO is used as an abutment surface 21 for arm main body lO.

Further, a mounting hole 22 of a predetermined diameter is formed at the center of the semicircle on the side opposite to the contact surface 21, passing through it from side to side.

The outer circumferential surface (including the contact surface 21) excluding the left and right side surfaces 23 and 23 and the mounting hole 22 are formed of a reinforcing member formed to a predetermined thickness from a material having a predetermined strength, and other parts The buffer portion 24 is made of a material having a predetermined elasticity such as rubber.

Then, the abutting surfaces 21 of the boss 2 are fixed to both end surfaces 11, 11 of the arm body 10 with adhesive to form an integral body, and furthermore, fibers impregnated with resin by filament winding molding are applied to the upper surface F in the longitudinal direction. The outer circumferential layer 3 is formed by continuously winding the outer layer 3.

With the above configuration, when compressive force is applied to the suspension arm L, the boss 2
The direction of the pressure F applied to the arm body IO is parallel to the edge line direction 10A, which has high strength, and no force is generated in the direction of tearing the fabric edge.

Note that the distance from the center of the mounting hole 22 to the end surface 11 of the arm body 10 is not uniform depending on the angle from the center of the mounting hole 22. Although the stress generated is different, such problems can be solved by forming slits in suitable locations in the cushioning material 1 to adjust the stress.

(Effect of the invention) According to the above-mentioned FRP suspension/arm structure in the city related to Unexploded 1!1, one contact surface between the arm body and the post member is 6. By making the plane straight, the compressive force is applied only in the direction of the fibers, which have strong mechanical strength, and the generation of cracks in the direction parallel to 1 am can be prevented.

Further, special equipment for processing the end face into an arc shape is not required, and addition becomes easy. As a result, processing time can be shortened and surface accuracy can be improved.

Furthermore, when the arm body 10 is formed by drawing and forming the arm body 10, the processing cost is reduced and the material yield is improved.

In addition, the shape of the boss member in the longitudinal direction of the suspension and arm is asymmetrical, and the direction of attachment to the arm body 10 is limited, making it easy to specify the direction when manufacturing one part and to assemble it once. .

In other words, * F of a vehicle that is easy to shape and process and has high durability.
It is possible to obtain a suspension arm made of RP.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing one embodiment of the present invention, Fig. 2 is an exploded perspective view thereof, Fig. 3 is a detailed view of the end portion, Fig. 4 is a view showing the compressive stress thereof, and Fig. 5 is a vehicle 6 is a perspective view of a conventional example, FIG. 7 is a partial view showing its processed state, and FIG. 8 is a diagram showing its compressive stress. 1...Suspension arm 2...Boss (boss member) 21...''!!1 Contact surface (plane that meets the end surface of the arm body) 3...Outer peripheral layer lO...Arm body 11. ...End face (longitudinal end face) Fig. 3 Fig. 7 Fig. 8 0A

Claims (1)

[Claims] An arm body is formed of FRP with its fiber direction aligned in the longitudinal direction, and both end faces in the longitudinal direction are planes perpendicular to the longitudinal direction, and a plane that comes into contact with the end face of the arm body is formed. forming a boss member having the arm body, and abutting the boss member on both end surfaces of the arm body, and wrapping resin-impregnated fibers around the arm body and the bush members at both ends in the longitudinal direction to form an outer peripheral layer. An FRR suspension arm structure for a vehicle, which is characterized by: