JPH0316819A - Vehicle suspension structure - Google Patents

Abstract

PURPOSE: To simplify the constitution and the manufacture and vary stiffness according to the wheel motion by providing a wheel support knucle with a support means for receiving vertical load, disposing a transversely extending leaf spring adjacent to the knuckle, and connecting the support means and the end of the leaf spring to each other by an elastic means. CONSTITUTION: An axle 18 is supported like a cantilever on a wheel support knuckle 16, a cantilever-like support plate 26 is integrated with the knuckle, and an upward lip 28 is formed on the end of the support plate 26. A leaf spring 22 extending over the whole lateral width of the vehicle is disposed adjacent to the wheel support knuckle 16, and the tip of the spring end 24 is positioned on this side of the support knuckle 16. The spring end 24 and the support plate 26 are connected to each other in such a manner as to be enclosed with a box-shaped member 30 formed of flexible elastomer reinforced by a continuous filamentary reinforcement material. By this arrangement, the constitution is simplified, and stiffness is varied according to the travel of the wheel.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to suspensions for vehicles such as passenger cars.

More specifically, the present invention is directed to a suspension suitable for the rear wheels of a passenger car, but it is of course applicable to other vehicles as well.

Automotive suspension systems that utilize one or more lateral leaf springs are well known; such systems include:
Individual vehicles connected to it can be moved independently. In the case of front-wheel drive vehicles, it is advantageous to have each rear wheel move independently. In the most widely used automotive suspension systems, resilience is typically provided by a coil spring, and the spring operates between the arm and the vehicle structure at a location remote from the arm pivot axis. In such devices utilizing coil springs, the vehicle structure adjacent to the wheel must be designed to provide space to accommodate the coil spring, and the connection of the spring to the vehicle structure must be designed to provide space for the coil spring. They have to be designed to support the loads that occur, and these have become a problem. The present invention employs a single plate spring device and avoids the deficiencies encountered with conventional coil spring suspension systems.

[Conventional technology]

In the prior art, there are various suspension systems used depending on the type of vehicle. Generally, most prior art devices provide a rigid mounting structure between the wheel and its spring biasing system.

The present invention is disclosed in U.S. Pat. No. 4,281,851 (title: Spring Suspension, publication date:
August 4, 1981 Inventor: Vernon Br
This is an improved technology for the vehicle spring suspension system described in andt). The aforementioned patents show spring suspension systems for attaching spring members to an axle assembly and a vehicle body. Specifically, each rear wheel of the vehicle is supported by a single leaf spring arranged in seven longitudinal directions relative to the vehicle chassis. The kingpin and attached shark pension part are placed in the center of the leaf spring to attach the rear wheel. U.S. Patent No. 4,281.
As shown in FIG. 1 of No. 851, the front end 5 of the leaf spring 3 is cantilevered in a vertical direction perpendicular to the longitudinal direction of the leaf spring 3. The vertically arranged end 5 is
It acts on the front bracket bolted to the vehicle chassis, thereby properly transmitting the loads of the front and rear wheels to the vehicle. The front end of the leaf spring 3 is seated on a bolt in a transverse position which is supported by the front bracket.

The rear end of the plate spring 3 is supported by a bolt in a lateral position supported by a rear bracket. The rear bracket and its associated bolt in a laterally oriented position therefore support only the vertical loads exerted on it by the rear end of the leaf spring 3.

The present invention differs from the above-described structure in that it incorporates pivotable connections at the front and rear of each spring to facilitate spring removal and maintenance. The present invention relates to techniques to relieve stiffness and allow vehicles to operate better.

U.S. Patent No. 4,619,466 (Title of invention: Wheel Suspensions Publication date: 19
October 28, 1986, Inventor: Waiter Sch
Able et al.) describe an automobile wheel suspension employing a leaf spring in a lateral orientation. Leaf springs are manufactured from composite fiber materials and are particularly suitable for front wheel suspension systems. The leaf spring is arranged between two transverse arms attached to the wheel support mechanism.

The tip of the leaf spring is fastened to the wheel support mechanism by a clamp whose surface is covered with elastomer. Bending the end of the spring causes the spring to move laterally through its clamp support mechanism. However, the clamp causes vertical as well as rotational movement as the spring end follows it. Therefore, a torque is exerted on the tip of the spring. The springs described in U.S. Pat. No. 4,619,466 are not only required to support sprung masses, but also to resist longitudinal bending loads coupled with torque movements from the wheel side.

The present invention is an improved technique for the suspension system described above, in which almost no torque is transmitted to the tips of the springs. The attachment structure on the spring end allows the spring to support the sprung mass while providing the desired flexibility in the desired plane.

Yet another spring support concept is described in U.S. Pat. No. 4,614,3.
No. 59 (Name of invention: Vehicle Wheel
with HeightAdjustment %Publication date: September 30, 1986, Inventor: Donald
G. Lundin et al.).

A transverse leaf spring is located at the rear of the vehicle between the sprung and unsprung masses of the vehicle. The leaf spring is made of a composite material such as glass fiber reinforced resin and is positioned between a pair of lateral control arms. The control arm is pivotally connected to the vehicle chassis and the wheel support knuckle. Wheel stability is also ensured by a trailing link, which is attached at one end to the chassis and at the other end to the wheel support knuckle.

The end of the leaf spring is located near the support knuckle,
There it is seated on a bolt attached to a support knuckle. The bolt shank is adjustable, thereby allowing the end of the leaf spring to be raised and lowered relative to the knuckle. By raising or lowering the sprung mass of the vehicle using the adjustment bolt, the relative height, posture, and height of the vehicle can be appropriately set. Because the support bolt contacts the underside of the leaf spring, the cantilevered end of the leaf spring does not support any load except vertical loads, and some Torque is generated in the plate spring.

Compared to the above-described spring support systems, the spring support concept of the present invention is such that the end of the spring supports the sprung mass of the vehicle, and the (rattling) rocking of the wheel has little effect on the spring; They differ in that bending is induced when the mass moves relative to the sprung mass.

[Summary of the invention]

The present invention provides a suspension for a pair of wheels of a vehicle having two arms, one on each side of the vehicle. Each arm is connected to the vehicle at one end and allows free vertical movement at the tip. The tip of the arm is connected to the wheel support structure by elastic means.

The plate spring of the present invention is preferably made of a fiber-reinforced composite plastic material. Leaf springs produced in this way have the advantage of being lightweight, as is well known for composite material leaf springs.

Such a selection of materials allows the leaf spring to be designed to suit all specific vehicle suspension requirements, especially those that vary the thickness or width of the leaf spring in its longitudinal direction. Can be designed. Using a leaf spring made of fiber-reinforced plastic material reduces the overall weight of the spring.

By means of a flexible box-shaped member, preferably formed in the form of a loop,
Each end of the leaf spring is connected to an adjacent wheel support structure. The box member provides an essentially vertical suspension between the leaf spring and the wheel support structure. Arranged to form a pension. The box member does not twist the spring, yet provides the desired flexibility in the required plane, and is provided as a lightweight, low-maintenance connection. simple height adjustment,
The ability to tolerate slight twists or tilts in the steering direction is also provided by the present invention.

The main object of the invention is to provide a vehicle wheel suspension system that has the desired elasticity and is simple and inexpensive to manufacture.

Still another object of the present invention is to provide a connection structure between a spring and a wheel suspension whose softness changes depending on the direction of movement and amount of movement of the wheel.

Yet another object of the present invention is to enable the relative height of the vehicle to be adjusted by means of a coupling structure between the spring and the wheel suspension assembly.

Yet another object of the present invention is to provide a composite spring with a mounting structure that minimizes the amount of torsion in the spring.

Yet another object of the present invention is to simplify the structure and reduce the number of components utilized in a vehicle suspension system.

Yet another object of the invention is to provide a spring-supported box-shaped member with a high degree of inelasticity in one direction, yet with an initial stiffness of approximately O in the other direction.

Yet another object of the invention is to provide a composite spring with a mounting structure that increases the life of the spring.

Still another object of the present invention is to enable the relative height of the vehicle to be adjusted longitudinally without disassembling the connection between the spring and the wheel support structure.

Other objects and effects of the present invention will be apparent from the claims and the following description based on the drawings attached to this specification. It should be noted that like parts are designated by like reference numerals in the various figures.

The present invention is not limited to the detailed structures and devices shown in the accompanying drawings; the present invention is capable of other embodiments and may be implemented in various ways according to the scope of the claims. Is possible. Furthermore, the terms and terminology used here are for explanation purposes only and are not for limitation purposes.

〔Example〕

In Figure 1 of the drawings, the left rear wheel assembly of a vehicle is shown in a perspective view from the rear of the vehicle.

The entire wheel assembly is designated at 10. The vertical axis 12 is
It extends in the longitudinal direction of the vehicle attached to the wheel assembly 10. As is common in most vehicles, the transverse axis 14 extends at right angles to the longitudinal axis 12. As shown, horizontal axis 1
4 corresponds to the axis of rotation of the wheel. Wheel support knuckle 1
6, an axle 18 extends outward in a cantilevered manner>,2,
Axle 18 is adapted to support a wheel indicated at 20.

Axle 18 is perpendicular to longitudinal axis 12 of the vehicle.

Although not shown, MacPherson (MacPher)
aon) It is common practice to attach a shock strut to the support knuckle 16 and the other end to the vehicle chassis to strengthen the overall suspension.

Furthermore, the support knuckle 16 is also pivotally mounted to the vehicle chassis so that its greatest degree of movement occurs in the vertical direction. The shock struts are not used as vehicle weight support devices, but are used to dampen the rocking motion caused by the wheels 20 while driving on the road. The main mass of a vehicle, sometimes referred to as the sprung mass, is supported by a spring system that typically consists of one or more springs located at each wheel of the vehicle. FIG. 1 shows the leaf spring 22 in a position parallel to the transverse axis 14 of the entire wheel assembly 1o.

In the present invention, the plate spring 22 can be made of steel;
It can also be made from a composite fiber-reinforced plastic material such as polyester or epoxy resin with unidirectional glass fibers embedded in it. Generally, the leaf spring 22 is formed to have a length that spans the entire width of the vehicle. The plate spring 22 is given a slight warp during initial assembly and molding.

This counter serves to deflect the sprung mass. For ease of explanation, the cross-sectional area of the leaf spring 22 shown in FIG. 1 is constant over its entire length, but springs with varying widths and thicknesses may also be used. Although not shown, the leaf spring 22 is fixed to the chassis of the vehicle near its longitudinal centerline. Both ends 2 of plate spring 22
4 projects like a cantilever toward the wheel 2o.

As is clear from FIG. 1, the tip of the spring end 24 is located in front of the support knuckle 16. Support knuckle 16
The wheel 2o is typically connected to the wheel by one or more struts, which maintain the wheel 2o along the longitudinal axis 12. The support knuckle 16 also has a cantilevered support plate 26 attached as an integral part thereto. Although the support plate 26 has a generally planar top surface, a cylindrical curved surface would work equally well in the present invention. An upwardly directed lip or flange 28 is formed at the end of the support plate 26.

The overall arrangement of the support knuckle 16 and the end 24 of the leaf spring 22 is such that the end 24 is spaced apart from and below the support plate 26. The end 24 of the leaf spring 22 is spaced laterally from the support knuckle 16, so there is no risk of interference.

A box-shaped member 30 is arranged to surround the spring end 24 and the support plate 26. The box-shaped member 3o is latched onto the top surface of the support plate 26 and the bottom surface of the spring end 24.

The box member is made of a flexible elastomeric material with continuous filament reinforcement arranged in an annular and banded manner. The elastomer used for the box-shaped member 3o can be rubber, polyurethane, or other flexible materials that are generally not permeable to solvents that may adhere in the vehicle environment. The filament reinforcing material can be polyamide such as nylon, Kepler, or glass fiber.

In plan view from above, the leaf spring 22 is relatively stiff, thus providing undesirable stiffness to the compliance of the suspension connection structure in the longitudinal direction. The leaf spring 22 is capable of vertical flexing motion and must not otherwise exert stiffness effects on the overall wheel assembly 10. The flexible box member 30 provides reasonable vertical stiffness and strength, but little initial stiffness in other directions. When a movement occurs between the support plate 26 and the spring end 24 along the longitudinal axis 12, the stiffness of the box-shaped member in the longitudinal plane increases progressively with increasing amount of movement.

Since the box-shaped member 30 has flexible properties, the support plate 2
6 and the spring end 24 is allowed.

The box-shaped member 30 is arranged in such a relationship that its vertical sides are essentially identical to each other. As a result, when a relative movement occurs between the support plate 26 and the spring end 24, the box-shaped member 30 assumes the shape of a parallelogram, such that the planar surface of the spring end 24 is always aligned with the support plate 24. parallel to the longitudinal part of the plate spring 22, thereby avoiding torsional loads being exerted on the leaf spring 22. The overall flexibility of the box member 30 allows it to act as a universal joint and support knuckle 16.
It is designed so that it can be tilted at a small steering angle.

FIG. 2 is a partially cutaway perspective view showing the interconnection structure between the wheel lower control arm 32 and the leaf spring 22, which shows yet another application of the flexible box suspension concept. An example is shown. The control arm 32 is a leaf spring 22
The box member 30 is positioned directly above the control arm 32 and the spring end 24 so that it surrounds both the control arm 32 and the spring end 24 .

To prevent the box member 30 from shifting from its initial installed position, the top surface 34 of the control arm 32 is provided with a protrusion, indicated generally at 36. The protrusion 36 is a box-shaped member 30
The box-shaped member 30 is disposed on both sides of the box-shaped member 30, and thus provides resistance to lateral displacement of the box-shaped member 30. In typical applications, the control arm 32 is pivotally attached to the support knuckle 16 of the wheel assembly 10.

FIG. 3 is an end sectional view of the box-shaped member 30 used in the present invention. The box-shaped member 30 can be formed by first forming a continuous tubular piece and then cutting it to the desired length. The reinforcing member is best placed in such a manner that it extends in the circumferential direction κ of the box-shaped member 30. Cutting the individual box-shaped members 30 from a long tubular stock has minimal impact on the reinforcement material κ disposed in the circumferential direction κ. Instead of forming a continuous tubular material, the individual box-shaped members 30 can be molded into the desired shape, including rounded corners as shown. In order to provide different degrees of adjustability, box-shaped member 30 can be formed with different dimensions, as shown by dashed line 3B.

FIG. 4 is a schematic cut-away side view of box member 30 and lower control arm 32 in the activated position.

The control arm 32 is most commonly formed of metal, such as a steel forging, and thus the protrusion 36 can be formed as an integral part thereof. In theory, a vehicle such as a car is symmetrical about a longitudinal axis, but in reality, due to manufacturing and assembly tolerances in parts, dimensions may vary from one side of the car to the other. There are some things that are different.

As a result, it is often necessary to place shims at the assembly site. In FIG. 4, the shim 40 is connected to the control arm 3.
2 and the top inner surface 42 of the box-shaped member 30. The shim 40 has an inclined flange 4 corresponding to both projections 36 of the control arm 32.
It has 4.

The slanted flange 44 of the shim 40 has an angle of 9 with respect to its body portion.
Since it is inclined at an angle smaller than 0 degrees, it is possible to stack a plurality of shims 40 and use two or more shims 40 at the same position. When the shim 4D is installed, a downward force is applied to the sprung mass of the vehicle on the plate spring 22,
Shim 40 is fixed in place.

FIG. 5 is a cross-sectional view of an embodiment of the invention. Support plate ゛26
is shown at the top of FIG. 5, and the plate 22 is shown at the bottom thereof. A strap 46 is positioned and fixed to the vertical edge 4B of the support plate 26. Similarly, the strap 46 is also attached to the vertical edge 50 of the leaf spring 22.

The strut 46 may be formed into a tubular structure and flattened during installation. The strap 46 does not necessarily have to be made of a tubular material; a single-piece strap 46 will work equally well in the present invention. Strap 4
6, a rigid mounting plate 52 is positioned between each two end layers of the flattened strap 46. The strut 46 and the mounting plate 5 included therein
2, the support plate 26 and the leaf spring 2 are connected by a plurality of bolts 54.
24l'il: Fixed. The strap assembly described above is very flexible in the sense that it can be installed and repaired without any disassembly of the entire wheel assembly 10. The paired strap assembly can be finely adjusted using adjustment means κ, which will be described below.

FIG. 6 is a cross-sectional view of another embodiment of the invention.

Support plate 26 and leaf spring 22 are shown spaced apart from each other. A slinder 56 is attached to one vertical edge 48 of support plate 28 by one or more bolts 54. A slit 56 passes around the bottom of the leaf spring 22 and is secured to the other vertical edge 48 of the support plate 26 with bolts 54 . In this way, there is no need to use bolts for the leaf spring 22. This is particularly important when the leaf spring 22 is made of a composite non-metallic material.

Attachment plates 52 are utilized on both top edges of the sling 560 as in the previous case. Sling 56 may also be adjusted as described in connection with FIG.

FIG. 7 is a cross-sectional view of a telescoping box structure with adjustment means provided on each free standing leg of the box structure. The outer box member 5B is combined with a telescoping inner box member 60. The circumferential length of the inner and outer box members 58,60 extends over their common surfaces.
．． 60 is adjusted so that they touch each other. The subassembly formed by the inner and outer box members 58,60 is placed in the mounting position as shown for the single box member 36 in FIG.

Box-shaped member 58. In order to adjust the mating condition of 60 for changes in the spacing between leaf spring 22 and support plate 26, insert 6 is preferably made of elastomeric composite-r.
2 is disposed between the inner and outer box-shaped members 5860. The insert 62 is located in the middle of the vertical portion of the box-shaped member 58, 60 extending between the support plate 26 and the leaf spring 22.

The thickness of the insert 62 can be varied to compensate for any parallelism deviation that may exist between the support plate 26 and the plate spring 22. Inserts 62 may also be utilized in the method of adjusting the sling 56 shown in FIG. 6 and the strannop 46 shown in FIG. The force of the leaf spring 22 in the direction F urges the strap 46 and sling 56, the vertical legs of the two-box member 5860, together, thereby securing the insert. As an additional measure against improper lateral movement of the insert, adhesives may be used, and securing members such as rivets (not shown) may be used.

ACTUATING AND ASSEMBLY In the installation of the plate 22 as shown in FIG.
The box member 30 is slid over the 7L portions overlapping each spring end 24 to secure the leaf spring 22 to the vehicle chassis. When the support knuckle 16 is installed, the spring end 24 can be moved towards the support plate 26 by means of a clamp or jack. Next, the box-shaped member 30 is moved to a suitable position 1, and the clamping force between the spring end 24 and the support plate 26 is gently released.

The present invention provides a novel Z wheel suspension in vehicle related operation. Particularly in vehicles powered by front-mounted engines, independent rear wheel suspension systems can be employed. Box-shaped member 30
and straps 46, slings 56, and telescoping inner and outer box members 5B, 60, respectively, permit lateral movement of the leaf 22 without adversely affecting the suspension characteristics as the wheel is raised or lowered. can. Furthermore, even if the rear wheel falls into a pothole, the box-shaped member 30 can still move without exerting excessive bending or torque moments on the leaf spring 22.

Although the present invention has been described above in connection with non-steered wheels of a vehicle, it can also be applied to steered wheels. The present invention can also be applied to non-motorized vehicles, such as trailers and semi-trailers, in the same way as to motorized vehicles.

Of course, the present invention is not limited to the embodiments described above, and various changes and modifications can be made without departing from the scope of the claims.

[Brief explanation of drawings]

Figure 1 is a perspective view of the left rear wheel of the vehicle showing the connection structure between the leaf spring and the wheel support assembly, and Figure 2 is a partially cutaway view of the connection structure between the lower control arm and the leaf spring. 3 is a cross-sectional view of a flexible link or box member utilized in the present invention; FIG. 4 is a schematic cutaway side view of the lower control arm, box member, and adjustment clip; and FIG. 5 is a plate. a cross-sectional view showing a variation of the flexible link connection structure between the spring and the adjusting wheel support structure;
FIG. 6 is a cross-sectional view of another variant of the box connection between the leaf spring and the wheel support structure; FIG. FIG. 10...●・Entire wheel assembly, shaft, 14●・◆・horizontal shaft, 16●● Tsukuru, 18-●●● axle, 20 22...●・plate spring, 24-●● 26●●●● Support plate, 30@●● ・●●● Control arm. 2...●Vertical/wheel supporter...●Wheel, leaf spring end, box-shaped member, 32

Claims (3)

[Claims] (1) A vehicle suspension structure for controlling the movement of a wheel support assembly of a vehicle having a plurality of wheels and a chassis, wherein: at least one wheel support knuckle is pivotally mounted to a portion of the vehicle chassis. an axle is provided integrally with the at least one wheel support knuckle, the axle is disposed generally horizontally and transversely to the vehicle chassis, and one of the plurality of wheels is attached to the axle; supporting a portion of the mass of the vehicle; supporting means connected to and extending from said at least one wheel support knuckle for acting on a load exerted in a generally vertical direction; a leaf spring is disposed adjacent to the wheel support knuckle and extends laterally of the vehicle; the support means and the end of the leaf spring are interconnected by elastic means, thereby reducing the sprung mass of the vehicle; A vehicle suspension structure characterized in that a portion of the suspension is elastically transmitted to the one of the wheels. (2) A vehicle suspension structure for controlling the motion of a wheel support assembly of a vehicle having a plurality of wheels and a chassis, wherein at least one wheel support knuckle is pivotally mounted to a portion of the vehicle chassis. an axle is provided integrally with the at least one wheel support knuckle, the axle is disposed generally horizontally and transversely to the vehicle chassis, and one of the plurality of wheels is rotatably mounted on the axle; a support means is attached to support a portion of the mass of the vehicle; a support means is connected to and extends from the at least one wheel support knuckle in a generally horizontal direction to act on loads exerted in a generally vertical direction; a leaf spring is disposed adjacent to said at least one wheel support knuckle and extends laterally of said vehicle; said support means and an end of said leaf spring are connected by resilient means having a plurality of load bearing members; a portion of the vehicle sprung mass elastically interconnects the vehicle sprung mass with
A vehicle suspension structure characterized in that the vehicle suspension structure is configured to transmit the following information. (3) A vehicle suspension structure for controlling the movement of a wheel support assembly of a vehicle having a plurality of wheels and a chassis, wherein at least one wheel support knuckle is pivotally mounted to a portion of the vehicle chassis. an axle is provided integrally with the at least one wheel support knuckle, the axle is disposed generally horizontally and transversely to the vehicle chassis, and one of the plurality of wheels is rotatably mounted on the axle; a support means connected to the at least one wheel support knuckle and extending therefrom in a generally horizontal direction and laterally toward the center of the vehicle; a leaf spring disposed adjacent to the at least one wheel support knuckle and attached to the vehicle chassis so as to extend in a lateral direction of the vehicle; a plurality of load bearing members; resilient means having a substantially vertical position, the resilient means interconnecting the support means and the end of the leaf spring such that a portion of the vehicle sprung mass resiliently A vehicle suspension structure characterized in that the transmission is transmitted to one body.