JPH02231205A - Frp spring used concurrently as suspension arm - Google Patents

Abstract

PURPOSE:To make construction simple and compact by rigidly fixing the fixing end of a combination arm and spring on the side of a car body, and installing, on its free end, a housing with a ball joint for swingingly supporting a hub carrier. CONSTITUTION:A cantilever type combination arm and spring 1 made of FRP is used for a suspension. In this case, the combination arm and spring 1 is extended in the direction of car width, and its fixing end 2 is rigidly secured onto a member 4 in the middle of car body with a metal bracket 3 as a fixing means. On the other hand, an end member 11 is affixed to the free end of the combination arm and spring 1. The end member 11 is fixed at a ball joint fixing part 14 of a housing 12, together with a ball joint 16, and a hub carrier 17 is swingingly supported by the ball joint 16. Furthermore, a axle shaft and a strut damper 18 are installed on the hub carrier 17.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an FRP spring that also serves as a suspension arm used in a suspension mechanism of a vehicle such as an automobile.

[Prior Art] A vehicle front suspension called a MacPherson strut has a lower arm that supports the lower end of the hub carrier so that it can swing, and an oil damper and a coil spring that supports the upper end of the hub carrier so that it can move up and down. I have to. However, since the coil spring has a spring seat with a large upward protrusion and a large outer diameter, the space ζ required to store the upper part of the coil spring becomes a cause of narrowing the interior space of the vehicle.

As shown in Patent Application Publication No. 58-501628, a structure without such a coil spring has hubs at both ends of an FRP (fiber reinforced plastic) arm extending in the vehicle width direction. A suspension has been proposed in which a ball joint for carrier support is provided, and a pair of left and right hub carriers are swingably supported via these left and right ball joints.

[Problems to be Solved by the Invention] In the above-mentioned prior art, since a long FRP arm extending between the pair of left and right wheels is used, this arm crosses under the engine room or under the vehicle body. For this reason, there are significant restrictions when designing the layout of the vehicle. In addition, the structure is such that a collar is inserted into a hole made at the end of the arm, and a ball joint is fitted inside this collar, so in order to fix a normal ball joint, a large hole of at least 40 mm in diameter is required. Must be drilled into the FRP arm. Therefore, in a composite material reinforced with fibers such as FRP, there is a high possibility that damage will occur from the periphery of the hole.

Therefore, an object of the present invention is to provide an FRP spring that can also be used as a suspension arm, which has a small amount of spring protrusion in the vertical direction, etc., has a simple and compact structure, and can widen the degree of freedom in designing the layout of a vehicle. There is a particular thing.

[Means for Solving the Problems] The FRP spring of the present invention developed to achieve the above object is provided independently on the left and right sides of the vehicle body, each extending in the width direction of the vehicle body, and extending in the vertical direction. A pair of left and right cantilever-shaped FRP springs that can be elastically bent, each fixed end is fixed to the vehicle body side by a fixing means, and a hub carrier is swingable on the free end side. It is characterized in that a housing having a ball joint for support is attached.

[Function] The FRP spring that also serves as a suspension arm with the above structure functions as a structural member for supporting the hub carrier, and also functions as a suspension spring. In other words, the load on the vehicle body is supported by the elasticity of each FRP spring, and the left and right FRP springs elastically bend independently in response to vertical inputs caused by unevenness of the road surface while driving. Shock is absorbed.

FRP springs have a lower Young's modulus than conventional steel springs, and can be deflected much more.

[Example] An example of the present invention will be described below with reference to the drawings.

FIG. 1 illustrates one of the left and right MacPherson type front suspensions of an automobile.

For these left and right suspensions, mutually independent FRP cantilever-shaped suspension arm springs 1 are used.

Similar to known FRP spring plates, this arm-combined spring l is made of matrix resin and continuous reinforcing fibers mainly along the longitudinal direction, so that it forms a slightly upwardly curved band in the free state. Molded.

The cantilever-shaped arm spring 1 extends in the vehicle width direction, and its base end, that is, the fixed end 2, is rigidly attached to a member 4 on the center side of the vehicle body by a metal bracket 3, which is an example of a fixing means. Fixed.

As shown in FIGS. 2 to 4, the flat box-shaped bracket 3 has an opening 5 at one end (the side into which the spring 1 is inserted). Moreover, this bracket 3
is formed in a tapered shape that widens at the back such that the width Wl on the opening 5 side is narrower than the width W2 on the back side when viewed from above. The flange-shaped mounting base 6 is rigidly fixed to the vehicle body member 4 using appropriate fastening parts 7 such as bolts or rivets.

Inside the bracket 3, a thermoplastic elastic layer 8 made of a thermoplastic polymer material is adhered to the entire outer periphery of the arm spring 1. Furthermore, rubber-like elastic material is applied to fill the gaps between the end surface of the arm spring 1 and the bracket 3, and between the thermoplastic elastic layer 8 and the bracket 3 located on both sides of the arm spring 1. Body 9 is loaded. The rubber-like elastic body 9 is made of a polymeric material having rubber-like elasticity, such as urethane elastomer, for example,
The end surface of the arm spring 1 and the portions in contact with the bracket 3 and the thermoplastic elastic layer 8 are all fixed with an adhesive. Therefore, the fixed end 2 side of the arm spring 1 has a certain angular range θ0 in the longitudinal direction of the vehicle body, with the artificial corner C of the opening 5 of the bracket 3 as a fulcrum, as shown by the two-dot chain line in FIG. It can oscillate.

The thermoplastic elastic layer 8 and the rubber-like elastic body 9 prevent the fixed end 2 of the arm spring 1 from being worn out, and also serve to equalize the tightening surface pressure applied to the fixed end 2. Therefore, the thermoplastic elastic body layer 8 and the rubber-like elastic body 9 serve as the arm spring 1.
It is preferable to use, for example, an elastomer reinforced with fibers so that it has a hardness of less than or equal to that of , has appropriate elasticity and flexibility, and will not be crushed even when subjected to repeated loads.

An end member 11 is attached to the other end of the arm spring 1, that is, to the free end 10 side. This end member 11 is constructed as shown in FIGS. 5 and 6.

The housing 12, which forms the main part of the end member 11, is made by bending a thick metal plate into the following shape. That is, the housing 12 includes a first support wall 13 that is bent into a substantially rectangular shape when viewed from the side (FIG. 5). The tip side of the first support wall 13 is a ball joint attachment part 14, and the joint attachment part 14 is inclined upward by an angle θ1 with respect to the arm attachment part 15. A ball joint 16 is fixed to the joint attachment portion 14, and a hub carrier 17 is swingably supported by this pole joint 16. An axle and a strut damper 18 are provided on the hub carrier 17. Therefore, the load point is located near the center of the ball joint 16.

19 is a tire.

The first support wall 13 is superimposed on one surface (lower surface side in the figure) of the arm spring 1 via a sheet-like liner 20 made of a rubber-like elastic body. Liner 20 is arm spring 1
and the first support wall 13 using an adhesive.

A pair of side walls 21 rising on both left and right sides of the first support wall l3.
22 faces the side surface of the spring 1 which also serves as an arm. A second support wall 23.24 connected to the upper end of these side walls 21.22
are bent inward to face each other. Note that the second support walls 23 and 24 may have a box shape in which they are connected to each other. The side walls 21, 22 are tapered at an angle θ2 such that the height h2 at the other end is lower than the height hl at one end (right side in the figure) when viewed from the side. Therefore, the height of the second support walls 23 and 24 also gradually decreases from the right side to the left side in the figure.

A metal seat plate 31 made of steel or the like is superimposed on the upper surface side of the arm spring 1 as shown in the figure, with a sheet-like litchi 30 made of a rubber-like elastic body interposed therebetween. Litchi 30 is arm spring 1
and the seat plate 31 with adhesive. liner 20
, 30 are useful for preventing wear of the arm spring 1 and also for equalizing the tightening surface pressure applied to the arm spring 1. Therefore, Litchi 20.30 has a hardness lower than that of the arm spring 1, and also has appropriate elasticity and flexibility, and is made of elastomer fibers, for example, so that it will not be crushed even under repeated loads. It would be best to use something that has been strengthened.

The wedge spring 32 interposed between the seat plate 31 and the second support walls 23 and 24 is made of a strong material with spring elasticity, such as hardened steel, and has a U-shaped or V-shaped shape in side view.
It is bent into a slightly open shape. wedge spring 32
The outer edges 33, 34 at both ends of the seat plate 31 and the second
It is rounded to improve the bite against the support walls 23 and 24. The width Wo of the wedge spring 32 is the width of the side wall 21.2.
It should be slightly narrower than the distance between the two. wedge spring 32
The opening angle θ3 in the free state is larger than the Taber angle θ2 of the side wall 21.22.

The wedge spring 32 is attached to the second support wall 23, . 24 and seat plate 31
It is driven from the right side in the figure between the two.

The caulking portion 41.42 used as detent means 40 for fixing the wedge spring 32 recesses a portion of the side wall 21.22 inwardly after the wedge spring 32 has been driven into said predetermined position. This caulking part 41.42
This prevents the wedge spring 32 from moving in the direction in which it comes off. As the detent means 40, the wedge spring 32 may be fixed to the housing 12 by, for example, welding or brazing instead of the caulking portions 41, 42.

Furthermore, holes 45 are provided in the vicinity of the plate end on the free end 10 side of the arm-combining spring 1, in the seat plate 31, and in the first support wall 13, each passing through in the thickness direction.

A bolt 46 is inserted into this hole 45, and a nut 47 is screwed in and tightened to connect the vicinity of the plate end of the arm spring 1, the first support wall 13, the liners 20, 30, and the seat plate 30.
etc. are restrained from each other in the thickness direction. Note that instead of using the bolt 46 and nut 47, a fastening member such as a rivet may be used.

According to the fixing structure of the end member 11 configured as described above, the arm spring 1 and the housing 12 are firmly crimped and fixed to each other by the wedge spring 32, and the litchi 20.
Since the spring 30 functions as a buffer material, the arm spring 1 and the end member 11 are prevented from relative movement such as rubbing against each other in the longitudinal direction. Therefore, problems such as the reinforcing fibers of the arm spring 1 being cut due to friction do not occur. Further, the number of holes 45 provided in the arm spring 1 can be reduced, and even if the inner diameter of the holes 45 is small, the function can be fully exhibited, so there is no problem in terms of strength even if the holes 45 are provided.

The shape of the FRP spring 1 that also serves as an arm may be such that the portion on the free end 10 side inserted into the housing 12 is inclined by an angle θ4 as shown in FIG. 7, or as shown in FIG. , the portion on the free end 10 side may be formed into a curved shape having a gentle curvature like the other portions.

Alternatively, a predetermined spring constant may be obtained with a shorter span by forming a tapered leaf shape in which the plate thickness gradually decreases from the fixed end 2 toward the free end 10.

However, even if the FRP spring 1 that also serves as an arm has the same width and thickness in the longitudinal direction, the intended purpose of the present invention can be achieved.

[Effects of the Invention] According to the present invention, the FRP spring that also serves as a suspension arm, which is provided independently for each of the left and right wheels, functions as both a suspension spring and a lower arm, and is not used in a conventional suspension mechanism. This makes it possible to eliminate the previously used suspension coil springs, making the suspension more compact and the structure simpler, and requiring fewer parts. In addition, the FRP spring that also serves as an arm of the present invention is of a cantilever type, and each extends independently in the vehicle width direction, so that the FRP spring does not cross the widthwise center of the vehicle body, engine room, etc. , which increases the degree of freedom in designing the layout of the car.

[Brief explanation of the drawing]

Fig. 1 is a front view of a suspension mechanism section equipped with an FRP spring that also serves as an arm, showing an embodiment of the present invention, and Fig. 2 is a bottom view of a spring fixing bracket in the suspension mechanism section shown in Fig. 1.
Figure 3 is a cross-sectional view taken along line 1--2 in Figure 1, Figure 4 is a cross-sectional view taken along line IV-IV in Figure 1, and Figure 5 is the suspension mechanism shown in Figure 1. FIG. 6 is a plan view of the ball joint mounting portion, and FIGS. 7 and 8 are front views showing modified examples of the FRP spring that also serves as an arm. DESCRIPTION OF SYMBOLS 1... FRP spring that also serves as an arm, 2... Fixed end of the spring, 4... Member on the vehicle body side, 10... Free end of the spring, 1
1... End member, 12... Housing, 16... Ball joint. Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Claims] A pair of left and right cantilever-shaped FRP springs that are provided independently on the left and right sides of the vehicle body, each extending in the width direction of the vehicle body, and capable of elastically bending in the vertical direction. An FRP that also serves as a suspension arm, the end of which is fixed to the vehicle body side by a fixing means, and a housing having a ball joint for swingably supporting a hub carrier is attached to the free end side.
Spring.