JPH0354010A - Suspension of automobile - Google Patents

Abstract

PURPOSE:To make compatible the compliance in the front and rear direction and caster rigidity upon braking operation by mutually connecting ends of radias rods of which rear ends are connected to the intermediate parts of upper and lower control arms respectively, and supporting them resiliently at a vehicle body. CONSTITUTION:Fore ends of upper and lower control arms 7, 8 are connected to the upper and support arms 4, 5 of a knuckle supporting a wheel 1 via boll joints 10, 11, respectively. The basic ends of the control arms 7, 8 are pivotally mounted on a vehicle body B through pivotal shafts 16, 17 and resilient bushes 19, 20. The rear ends of upper and lower radial rods 24, 25 are connected at the intermediate part between the arms 7, 8 so as to swing freely via upper and lower resilient connection means 26, 27 outside a rim. The front ends of the rods 24, 25 are fixed to a support board 28, and this board 28 is pivoted to the body B via a shaft 29 and a resilient bush 30.

Description

[Detailed Description of the Invention] A. OBJECTIVE OF THE INVENTION ()) Industrial Field of Application The present invention relates to a suspension system for an automobile, and more particularly, to a suspension system for an automobile, in particular, a suspension system for an automobile, in which the base ends of a pair of upper and lower upper and lower control arms connected to a knuckle supporting a wheel are attached to a vehicle body. This invention relates to the improvement of a device that is pivoted so as to be able to swing up and down.

(2) Prior Art Such a suspension system is widely known as a double wishbone type (see, for example, Japanese Patent Publication No. 44-28123). (3) Problems to be Solved by the Invention In such a conventional suspension system, the base ends of the upper control arm and the lower control arm are pivoted to a horizontal shaft fixed to the vehicle body through respective elastic support members. Therefore, the longitudinal conformance and the caster rigidity during braking are influenced by the spring constants of these elastic members.

First, in order to minimize the transmission of shock to the car body when the wheels go over a protrusion on the road surface, it is necessary to increase the longitudinal compliance of the traverse system, and also to increase the straightness of the wheels during braking. In order to ensure this, it is necessary to increase the caster rigidity of the carriage system.

However, in the conventional suspension system, if the spring constant of the elastic support member is set small in order to obtain a large longitudinal conformance, the caster rigidity decreases and the straightness of the wheel is impaired, and the caster rigidity during braking decreases. If the spring constant of the elastic support member is set to a large value in order to obtain a large value of Have difficulty. Therefore, even if the elastic support member is given nonlinear spring characteristics,
It is not possible to ensure longitudinal compliance during braking.

The present invention has been made in view of the above circumstances, and provides a simple and effective suspension system that can satisfy both longitudinal compliance and caster rigidity during braking, and also improve ride comfort even during braking. The purpose is to provide.

B. Structure of the Invention (1) Means for Solving the Problems In order to achieve the above object, the present invention connects the tips of an upper control arm and a lower control arm to a knuckle within the rim of a wheel, and The rear ends of the upper radius rod and the lower radius rod are connected to the intermediate parts of the upper control arm and the lower control arm on the outside, and the front ends of both radius rods are connected to each other, and the vertical swing is applied to the vehicle body via an elastic support member. It is characterized by being pivoted for free movement.

(2) Effect According to the above structure, when braking, the moment acting on the wheel from the road surface causes a compressive force to act on one of the radius ronds and a tensile force on the other, so the resultant force is the compressive force and tensile force mentioned above. smaller than Therefore, the amount of deformation of the elastic support member that supports the front ends of both radius rods due to the above-mentioned resultant force is relatively small, thereby ensuring caster rigidity of the suspension system. Also, if a load is applied to the center of the wheel in the longitudinal direction,
Since only tensile force or only compressive force acts on both radius rods, the resultant force is larger than each of the above-mentioned tensile forces or compressive forces. Therefore, the amount of deformation of the elastic support member due to the resultant force is relatively large, and as a result, it is possible to obtain a large longitudinal conformance of the suspension system.

Moreover, since the ends of the upper and lower control arms are connected to the knuckles within the wheel rim, these connection points can be placed close to the wheel rotation center plane, and as a result, the wheels receive loads from the road surface. It is possible to minimize the load burden on each control arm when The rear ends of the upper and lower radius rods are connected to the intermediate parts of the lower control arm and the lower control arm outside the wheel, so each radius rod can be shaped into a straight line or a shape close to that without being interfered with by the wheel. can increase its thrust or hold function.

(3) Example An example of the present invention will be described below with reference to the drawings. Figure 1 shows a left rear suspension system S for an automobile to which the present invention is applied.
2 is a plan view thereof, and FIG. 3 is a side view thereof. In these figures, a knuckle 2 for supporting the wheel l is connected to a spindle 3 that supports the wheel l via a bearing 23 (Fig. 2), and to three directions upward, forward, and rearward from the base end of the spindle 3. It has an upper support arm 4, a lower support arm 5, and a rear support arm 6 that respectively project to the upper and lower support arms 4, 5, and the tips of the upper and lower control arms 7, 8 are connected to the rim of the wheel l, respectively. The tip of the auxiliary control arm 9 is connected to the rear support arm 6 via a ball joint 10.11 within the rim l.
a connecting shaft l2 and an elastic pusher 1 surrounding them;
5.

The above control arms 7, 8.9 are respectively! They are shaped like molds and arranged in the vehicle width direction, and their base ends are pivotally connected to the vehicle body B via pivots 16, 17, 18 in the longitudinal direction of the vehicle and elastic pushers 19, 20, 21 that surround them. . Therefore, these control arms 7, 8.9 can freely swing upwards around the pivot shafts 16, 17, 18, and can also swing slightly in the front-back direction due to the deformation of the elastic pushers 19.2'0.21. be.

A damper D with a suspension spring is interposed between the knuckle 2 and the vehicle body B.

The upper and lower control arms 7.8 are
The rear ends of the upper and lower radius rods 24.25 are swingably connected to each other via upper and lower elastic connection means 26.27, respectively, at an intermediate portion close to the inner surface of the Iial.

Further, the front ends of both radius rods 24 and 25 are connected to a common support plate 28 by bolts, welding, etc. so as to be fixed to each other. The support plate 28 supports the pivot shaft 2 in the vehicle width direction.
9 and an elastic pusher 30 made of rubber that is an elastic support member surrounding the pusher.

The elastic pusher 30 is provided with a pair of hollowed out portions 45 and 45 that are lined up front and back with the pivot 29 in between. By doing so, the spring constant of the elastic pusher 30 is set to be large in the vertical direction and small in the longitudinal direction. Furthermore, the elastic pusher 30 is provided with an elastic stopper 46 for restricting the forward displacement of the pivot shaft 29 by more than a certain amount. In the illustrated example, both radius rods 24, 25 are given appropriate bending elasticity, but either one of the radius rods 25, 25 may be provided with bending elasticity. Here, as shown in FIG. 3, a straight line l1 connecting the centers of the frame shaft 29 and the upper elastic connecting means 26 and a straight line l2 connecting the centers of the pivot 29 and the lower elastic connecting step 27 are formed. The included angle θ is set to an acute angle. In this case, the lower radius throat 25 is shaped like a straight line and is arranged on the straight line 12.

On the other hand, the upper radius slot 24 has its rear half disposed on the straight line 11, and its front half bent downward so as to be below the straight line 11. In order to effectively utilize the space above the front half of the upper radius rod 24 for the vehicle interior, a floor plate Ba of the vehicle body is arranged along the upper radius rod 24, and a seat 31 is mounted on the floor plate Ba on the front half of the upper radius rod 24. installed close to the

Next, the upper and lower elastic connecting means 26, 27 will be explained with reference to FIGS. 4 and 5.

First, the upper elastic connecting means 26 will be explained with reference to FIG. 4. The upper radius rond 24 is integrally provided with a pole 24a at the rear end that passes through the post 7a formed in the middle part of the upper control arm 7. This bolt 24a has a pair of outer supports Fi. 33 and 33 are fixed with nuts 34.

Each outer support plate 33 is provided with a tapered portion 33a that approaches the boss 7a as it goes radially outward, and an annular tapered portion 33a that fits into the opposite end of the boss 7a. A rubber annular elastic body 36 is joined between the inner support plate 35 and the inner support plate 35 . An annular shape-retaining plate 37 is embedded in the axially intermediate portion of this elastic body 36, and this shape-retaining plate 37
The outer support plate 33 is also provided with a tapered portion 37a similar to the outer support plate 33. The inner support plate 35, elastic body 36 and shape retaining plate 37 are
Both are arranged so as to surround the distance collar 32 with a gap in between.

Next, the lower elastic connecting means 27 will be explained with reference to FIG. 5. The lower radius rod 25 is integrally provided with a bolt 25a at the rear end that passes through a boss 8a formed in the middle part of the lower control arm 8. A distance collar 39 and a pair of outer support plates 40, 40 facing each other with the boss 8a in between are fixed to the bolt 25a with nuts 41. Each outer support plate 40 is provided with a tapered portion 40a that approaches the boss 8a as it goes outward in the radial direction, and an annular portion that fits into the tapered portion 40a and the opposite end of the boss 8a. Between the inner support temporary 42,
An annular elastic body 43 made of rubber is joined. The inner support plate 42 and the elastic body 43 are both arranged so as to surround the disk scalar 39 with a gap therebetween.

Taper portions 33a, 40a of each of the outer support temporary 33.40
, the perpendicular to the inner surface of each elastic connecting means 26,27
It is shaped like it passes through the center of.

Next, the operation of this embodiment will be explained. First, in Figure 6, while the car is running, play? Assume that the brake is applied to the wheel 1 by the operation of the device.

When the wheel l is braked, the frictional braking force P acting on the wheel l from the road surface G causes a moment m in the counterclockwise direction in the figure to act on the knuckle 2, and accordingly, both radius rods 24.
25, the straight line f. A compressive force P1 along the line l2 and a tensile force P1 along the straight line l2. act, and their resultant force P
, is applied to the elastic push 30 as a downward load.

Therefore, the two straight lines e. , i■ is set to an acute angle, so the resultant force P. is compressive force P1 or tensile force P
Less than 2. Moreover, since the spring constant of the elastic push 30 is determined to be large in the direction of the resultant force PA,
The amount of deformation of the elastic bundling 30 due to the resultant force PA is small, and as a result, the caster change of the wheel l is small, and the straightness of the wheel l can be ensured.

Further, in this case, even though the front half of the upper radius rod 24 is bent downward in order to make the vehicle interior as large as possible as described above, the rear half of the upper radius rod 24 is arranged on the straight line l1, The compressive force P, applied to the upper radius rod 24 from
In contrast, the component that causes bending load is extremely small.

Moreover, since the lower radius rod 25 is arranged on the straight line l2, the tensile force P2 applied from the knuckle 2 to the lower radius rod 25 becomes a simple tensile load.

As a result of the above, the lower radius rond 25 receives only a slight bending load, so it can be made using relatively thin nine rods, which can contribute to weight reduction.

Said compressive force P and tensile force l)t are also caused by the elastic body 36.43 between the outer and inner support plates 33.40:35, 42 approaching each other in the corresponding elastic coupling device 26.27.
acts as a simple compressive force on the elastic body 36.43
are prevented from protruding outward in the radial direction by the tapered portions 33a, 40a of the outer support plates 33, 40, so the amount of deformation of each elastic body 36, 43 is small, and therefore the caster of the wheel 1 due to the deformation changes. are extremely rare.

Next, in FIG. 7, it is assumed that the wheel l rides over a protrusion 44 such as a pebble on the road surface G while the vehicle is running. When the wheel l climbs the protrusion 44, the load Q applied to the rear of the vehicle from the protrusion 44 to the center of the wheel l is applied to both radius rods 24 and 25 via the knuckle 2 and to the two straight lines 1+ and lx. The tensile force along Q. ,Q. The resultant force Q. is applied to the elastic push 30 as a backward load. Therefore, the two straight lines I! ．． ,,ffi
．． Since the included angle θ between them is an acute angle, the resultant force QA is the tensile force Q,
and Q2. Moreover, since the spring constant of the elastic push 30 is set small in the direction of the resultant force QA, the amount of deformation of the elastic push 30 due to the resultant force QA is large. As a result, the suspension system S is given a large longitudinal conformance, and the impact force from the protrusion 44 can be effectively alleviated and prevented from being transmitted to the vehicle body B.

Furthermore, the resultant force PA. Since the acting directions of Qa are different from each other, sufficient longitudinal compliance can be ensured even during braking, and ride comfort during braking can also be improved. When the wheel l is raised or lowered or when braking, the above-mentioned included angle θ changes from the upper and lower control arms 7 and 8 to the upper and lower radius rods 24 and 25 due to the deformation of the elastic bodies 36 and 43.
Although a load is applied in a direction that increases or decreases more or less, the upper radius rod 24, the lower radius rod 25, or both 24.25 bend appropriately to allow the deformation of the elastic body 36.43. From this, both radius rods 24.
25 can be fixed to each other, and the structure can be simplified.

Particularly when the wheel 1 is raised or lowered, the upper and lower control arms 7, 8 and the upper and lower radius ronds 24.
25, a three-dimensional rotational displacement occurs between the outer support plates 33, 40 and the inner support plates 35.42 in each elastic coupling device 26.27, but the support plates 33.4
The joint portions with the elastic bodies 36, 43 of 0 are the tapered portions 33a, 4.
0a, the elastic body 36.43 receives shearing force from any rotational displacement and deforms relatively easily, allowing the wheel l to move up and down smoothly, and at the same time, a large torsional torque is applied to each radius slot 24.25. It is possible to prevent this from occurring.

In such a suspension system S, the ends of the upper and lower control arms 7.8 are connected to the knuckle 2 within the rim la of the wheel l, so that the proximity of these connection points to the wheel rotation center plane O is As a result, the wheel l
Each control arm 7 when receiving a load from the road surface
, 8 can be minimized.

In addition, the rear ends of the upper and lower radius rods 24.25 are connected to the intermediate portions of the upper and lower control arms 7, 8 outside the vehicle 1, so each radius rod 24.2
5 can be shaped into a straight line or a shape close to it without being interfered with by the wheels 1, so that its bracing or treading function can be enhanced.

Incidentally, the present invention can also be applied to a front suspension system of an automobile. In that case, it goes without saying that instead of the auxiliary control arm 9, a tie rod connected to the steering mechanism is connected to the rear support arm 6 of the knuckle 2 via a pole joint.

C. Effects of the Invention As described above, according to the present invention, when a braking force is applied to the wheel while driving, and when a longitudinal load is applied to the center of the wheel, the above. By varying the degree of force applied to the elastic support member that supports the front end portions of both lower radius rods, it is possible to obtain large longitudinal compliance while ensuring caster rigidity of the suspension system. Therefore, it is possible to satisfy both the straight-line performance during braking and the shock absorption performance when running on an uneven road surface, and also to improve the riding comfort during the il1 movement.

Additionally, since the ends of the upper and lower control arms are connected to the knuckles within the wheel rim, these connection points can be placed close to the wheel's center of rotation, allowing the wheels to receive loads from the road surface. In this case, the load on each control arm can be minimized, contributing to improved durability.

In addition, since the rear ends of the upper and lower radius rods are connected to the intermediate parts of the upper and lower control arms outside the wheels, each radius rod can be formed into a straight line or a shape close to it without being interfered with by the wheels. , enhances its thrusting or treading function, thereby making it possible to always maintain the proper posture of the wheel.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a perspective view of the left rear suspension system of an automobile, FIG. 2 is a plan view of the same, and FIG.
The figure is a sectional view taken along the line ■-■ in Fig. 2, Fig. 4 is an enlarged longitudinal sectional view of the upper elastic coupling means in Fig. 3, and Fig. 5 is an enlarged longitudinal sectional view of the lower elastic coupling means in Fig. 3. FIG. 6 is a side view illustrating the action during braking, and FIG. 7 is a side view illustrating the action when the wheel goes over a protrusion. B...Vehicle body, S...Suspension system, l...Wheel, la...Rim, 2...Nakuru,
3... Spindle, 7... Upper control arm, 8... Lower control arm, 24... Upper radius rod, 25... Lower radius rod, 29
...Axis, 30...Elastic push as an elastic support member Patent applicant Honda Motor Co., Ltd. Representative Patent attorney Kendojin Ochiai Kiichi Akira Figure 4 Figure 5

Claims (1)

[Claims] In an automobile suspension system, the base ends of a pair of upper and lower control arms are pivoted to the vehicle body so as to be able to swing vertically, the ends of which are connected to the knuckles that support the wheels. The ends of the upper control arm and the lower control arm are connected, and the rear ends of the upper radius rod and the lower radius rod are connected to the intermediate parts of the upper control arm and the lower control arm outside the rim, and the front ends of both radius rods are connected to each other. A suspension system for an automobile, characterized in that the suspension system is interconnected and pivotally connected to a vehicle body via an elastic support member so as to be able to swing vertically.