JPH09226333A - Suspension structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve rigidity of a caster. SOLUTION: An auxiliary bar 11 is suspended between trailing arm members 3 with a specified interval from an axle 2 and a central part of this auxiliary bar 11 is connected to a central part of the axle 2 in a suspension structure connecting each one end part of a pair of the trailing arm members 3 to the axle 2 and axially supporting the other end parts of these trailing arms 3 on a car body frame free to oscillate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension structure capable of improving caster rigidity.

[0002]

2. Description of the Related Art Among four-wheeled vehicle rear suspensions, there is a type called a three-link type suspension (also called an isolated trailing link type).

This three-link rear suspension is
As shown in FIGS. 11 and 12, the trailing arm 100 and the lateral rod 101 support the axle shaft 102 on the vehicle body frame 103, and the coil spring 104 and the shock absorber 105 suspend the axle shaft 102.

As the trailing arm 100 used in this three-link type rear suspension, for example, one shown in FIG. 13 is used. In this trailing arm 100, bushes 107 with outer cylinders are attached to both ends of the link body 106 (two at one end and one at the other end). The bush 107 with an outer cylinder is configured by pressing a rubber bush into the pipe 108. In the trailing arm 100, one end of the trailing arm 100 is pivotally supported by the bracket 111 of the axle shaft 102 by inserting the bolt 109 into the center hole of the bush 107 with an outer cylinder and screwing the nut 110 therein. The other end of the frame 103 is pivotally supported. Reference numeral 112 is a wheel supported by the axle shaft 102.

In such a three-link type rear suspension, generally, if the layout is the same, the roll rigidity and the caster rigidity are both proportional to the spring constant in the direction perpendicular to the axis of the rubber bush. Usually, when only the roll rigidity is desired to be increased, a stabilizer is added, but conventionally, there has been no method to increase only the caster rigidity. As described above, in the 3-link rear suspension, the caster rigidity depends on the hardness of the rubber bush.
For this reason, the hardness of the rubber bush is an important factor in the characteristics such as riding comfort and roll rigidity, and it cannot be unnecessarily hard to increase the caster rigidity, and as a result, the caster rigidity tends to be insufficient. As described above, when the caster rigidity is low, uncomfortable shocks are generated in the acceleration and deceleration of the drive wheels, and vibrations in the caster rotation direction occur. Further, if the caster rigidity is low, there are problems that the joint portion of the propeller shaft is angled, torque fluctuations occur, and the brake feeling deteriorates.

Therefore, in order to improve the rigidity of the casters, as shown in FIG. 14, a load arm 115 is provided between the shock absorber 113 and the trailing arm 114, and the rubber bush 1 is connected to both ends of the load arm 115.
There is known a prior art in which the input of the braking moment is also distributed to the axle beam 118 and the load arm 115 via 16, 117.
908 publication).

[0007]

However, according to such a prior art, since the shock absorber 113 receives the braking moment, the shock absorber 1 is not affected.
13 and all of the upper and lower mounts need high rigidity and high strength, and the overall suspension structure is large.
At the same time, there is a problem that it becomes heavy and expensive.

An object of the present invention is to solve the above problems and to provide a suspension structure capable of improving caster rigidity.

[0009]

In order to solve the above problems, the present invention connects one end of each of a pair of trailing arm members to an axle, and connects the other end of these trailing arm members to a vehicle body frame. In a suspension structure swingably supported, an auxiliary bar is laid between the trailing arm members at a predetermined distance from the axle, and the central portion of the auxiliary bar is swingable to the central portion of the axle. I have been connected.

The present invention also provides a suspension structure in which one end of each of a pair of trailing arm members is connected to an axle, and the other end of each of these trailing arm members is pivotally supported by a vehicle body frame. , An auxiliary bar is laid between the trailing arm members at a predetermined distance from the axle, and the other end of the auxiliary arm whose one end is connected to the center of the axle can be swung to the center of the auxiliary bar. It is connected to.

Further, according to the present invention, one end of each of the pair of trailing arm members is connected to the axle via a bush,
In addition, in a suspension structure in which the other ends of these trailing arm members are swingably supported by a vehicle body frame, an auxiliary bar is provided between the intermediate portions of the trailing arm members at a predetermined distance from the axle. , A bush is interposed between the auxiliary bar and the support portion of the trailing arm member, and the other end of the auxiliary arm, one end of which is connected to the central portion of the axle, is swingable to the central portion of the auxiliary bar. I have been connected.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

1 and 2 show a three-link type suspension according to the present invention, in which 1 is a body frame,
Reference numeral 2 is an axle shaft (axle), 3 is a trailing arm (trailing arm member), and the axle shaft 2 is swingably supported on the vehicle body frame 1.
4 is a suspension device for suspending the axle shaft 2, and a spring 5
And a shock absorber 6. 7 is 3
It is a lateral rod that constitutes one of the links and is laid between the axle shaft 2 and the body frame 1.

One end of the trailing arm 3 is connected to the axle shaft 2 via two rubber bushes 8b with an outer cylinder.
Is rotatably supported by a bracket 9 provided on the vehicle body frame 1 at the other end via a rubber bush 8a with an outer cylinder.
It is pivotally supported by the bracket 10 attached to the.

Reference numeral 11 denotes an auxiliary bar which is stretched between the substantially intermediate portions of the trailing arm 3, and both ends of the auxiliary bar 11 are supported by the trailing arm 3 via bushes 12, respectively. . Reference numeral 13 denotes an auxiliary arm having one end connected to the central portion of the axle shaft 2, and the other end of the auxiliary arm 13 is swingably connected to the central portion of the auxiliary bar 11.

A rubber bush 14 with an outer cylinder is rotatably attached to the other end of the auxiliary arm 13 as shown in FIGS. 3 and 4, and the outer cylinder 15 of the rubber bush 14 with the outer cylinder is attached. The outer peripheral surface is welded to the auxiliary bar 11. The rubber bush 14 with an outer cylinder has a cylindrical rubber bush 16 inside the outer cylinder 15.
The shaft portion 17 of the auxiliary arm 13 is rotatably inserted into the inside of the. A screw portion 17a is provided at the end of the shaft portion 17, and the rubber bush 14 with an outer cylinder is attached to the screw portion 17a.
, And the nut 18 is screwed onto the end of the threaded portion 17a to attach the rubber bush 14 with the outer cylinder. As shown in FIG. 4, the rubber bush 16 is provided with hollow portions 19 on both sides of the central axis to reduce the rigidity of the auxiliary bar 11 in the axial direction (X direction), and to reduce the rigidity in the vertical direction orthogonal to the auxiliary bar 11 ( The rigidity in the Z direction) is obtained. The rubber bush 16 is slidably attached to the shaft portion 17 of the auxiliary arm 13 and is freely movable in the Y direction shown in the drawing (see FIG. 3).

On the other hand, as shown in FIGS. 5 and 6, the auxiliary bar 11 is rotatably supported by being inserted into a cylindrical bush 12 mounted on the trailing arm 3, and is axially (X Direction) and vertically (Z
Direction) is supported.

FIG. 7 shows the operation of the embodiment with the above configuration.
The description will be given with reference to (a), (b) to FIGS. 9 (a), (b). 7 (a) and 7 (b) show the state during acceleration. At the time of acceleration, a clockwise torque reaction force f _{1 in} the direction of the arrow in the figure is generated on the axle shaft 2. This torque reaction force f
_1, the support bar 11, by moving as shown by the two-dot chain line in FIG. 7 (b), as indicated by the arrow f _2, say the left and right trailing arms 3, the axle shaft 2 trailing arm It works so as not to rotate with respect to 3. When braking, the operation is in the opposite direction. Next, as shown in FIG.
(B) shows when both wheels are in the same direction stroke.
When the two wheels stroke in the same direction, no force acts on the auxiliary bar 11, and the auxiliary bar 11 rotates entirely around the bush 8a. FIG. 8 (a)
The arrow indicates the axle shaft 2 when both wheels stroke in the same direction.
It is a description of the movement of. The arrow in FIG. 8B indicates the left and right trailing arms 3, the rubber bush 14 with an outer cylinder,
This shows that the auxiliary bars 11 all move in the same direction by the same amount. 9 (a) and 9 (b) show the time of rolling. During rolling, the auxiliary bar 11 rotates around the rubber bush 14 with the outer cylinder, for example, in the direction of the arrow in FIG. 9B, and the trailing arm 3 moves in the left and right directions. At this time, since the auxiliary bar 11 slides in the bush 12 of the trailing arm 3 in the axial direction, no reaction force is generated,
It does not resist the roll.

FIG. 10 shows an embodiment in which the present invention is applied to the axle shaft 2 of the drive wheel. In this case, the rubber bush 14 with an outer cylinder is attached to the differential gear box 21 directly connected to the propeller shaft 20 via the bracket 22.
The auxiliary bar 11 is inserted through the center hole of No. 4. In this way, the auxiliary arm 13 can be omitted.

[0020]

As described above, according to the suspension structure of the present invention, the following effects can be obtained. The suspension structure according to claim 1, wherein one end of each of the pair of trailing arm members is connected to an axle, and the other end of each of the trailing arm members is pivotally supported by a vehicle body frame. Auxiliary bar is laid between the arm members at a predetermined distance from the axle, and the central part of this auxiliary bar is swingably connected to the central part of the axle, so an auxiliary bar is added to the conventional suspension structure. By doing so, only the rigidity of the caster can be improved. In addition, since the bush provided between the trailing arm member and the axle, etc. does not need to be hardened in order to increase the rigidity of the caster,
By making this bush soft, it is possible to improve riding comfort and steering stability. Furthermore, since the caster rigidity can be improved, it is possible to reduce the interference with other parts due to the rotation of the axle. Since the torque reaction force generated during acceleration and deceleration is not received by the bush or the like, the durability of the bush or the like is improved. The suspension structure according to claim 2, wherein one end of each of the pair of trailing arm members is connected to an axle, and the other end of each of the trailing arm members is pivotally supported by a vehicle body frame. Since the auxiliary bar is bridged between the arm members at a predetermined distance from the axle, and the other end of the auxiliary arm whose one end is connected to the center of the axle is swingably connected to the center of the auxiliary bar. By adding an auxiliary bar and an auxiliary arm to the conventional suspension structure, only the caster rigidity can be improved. Also, since it is not necessary to make the bush provided between the trailing arm member and the axle hard to increase the rigidity of the caster, the bush is softened to improve riding comfort and steering stability. Can be planned. Furthermore, since the caster rigidity can be improved, it is possible to reduce the interference with other parts due to the rotation of the axle. Since the torque reaction force generated during acceleration and deceleration is not received by the bush or the like, the durability of the bush or the like is improved. In Claim 3, each one end of a pair of trailing arm members is connected with an axle via a bush,
In addition, in a suspension structure in which the other ends of these trailing arm members are swingably supported by a vehicle body frame, an auxiliary bar is provided between the intermediate portions of the trailing arm members at a predetermined distance from the axle. , A bush is interposed between the auxiliary bar and the support portion of the trailing arm member, and the other end of the auxiliary arm, one end of which is connected to the central portion of the axle, is swingable to the central portion of the auxiliary bar. Since they are connected, only the caster rigidity can be improved by adding an auxiliary bar and an auxiliary arm to the conventional suspension structure. In addition, the bush provided between the trailing arm member and the axle,
Since it is not necessary to harden the caster to increase its rigidity, the bush can be softened to improve riding comfort and steering stability. Furthermore, since the caster rigidity can be improved, it is possible to reduce the interference with other parts due to the rotation of the axle. Since the bush does not receive the torque reaction force generated during acceleration and deceleration, the durability of the bush is improved.

[Brief description of drawings]

1 is a partially cutaway side view showing a suspension structure according to the present invention.

FIG. 2 is a perspective view showing a suspension structure according to the present invention.

3 is a sectional view taken along line BB of FIG. 4 showing an auxiliary arm.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

5 is a cross-sectional view taken along line DD of FIG. 6 showing an auxiliary bar.

FIG. 6 is a sectional view taken along line CC of FIG. 5;

7A and 7B show an operation of the auxiliary arm at the time of acceleration, FIG. 7A is a side view, and FIG. 7B is a view in the X direction of FIG.

FIG. 8 shows the operation of the auxiliary arm during a two-wheel stroke,
(A) is a side view, (b) is a X direction arrow view of (a).

9A and 9B show the operation of the auxiliary arm during rolling, FIG. 9A is a side view, and FIG. 9B is a view in the X direction of FIG.

FIG. 10 is a conceptual diagram showing an embodiment in which an auxiliary arm is omitted.

FIG. 11 is a rear view showing a conventional suspension structure.

FIG. 12 is a side view showing a conventional suspension structure.

FIG. 13 is a perspective view showing a trailing arm member of a conventional suspension structure.

FIG. 14 is a conceptual diagram showing a conventional suspension structure.

[Explanation of symbols]

 1 Body Frame 2 Axle Shaft 3 Trailing Arm 4 Suspension Device 5 Spring 6 Shock Absorber 7 Lateral Rod 8a, 8b Rubber Bushing with Outer Cylinder 9 Bracket 10 Bracket 11 Auxiliary Bar 12 Bush 13 Auxiliary Arm 14 Rubber Bush with Outer Cylinder 15 Outer Cylinder 16 Rubber bush 17 Shaft part 18 Nut 19 Hollow part

Claims (3)

[Claims] 1. A suspension structure in which one end of each of a pair of trailing arm members is connected to an axle, and the other end of these trailing arm members is pivotally supported by a vehicle body frame. A suspension structure characterized in that an auxiliary bar is bridged between the arm members at a predetermined distance from the axle, and the central portion of the auxiliary bar is swingably connected to the central portion of the axle. 2. A suspension structure in which one end of each of a pair of trailing arm members is connected to an axle, and the other end of each of the trailing arm members is pivotally supported by a vehicle body frame. An auxiliary bar is laid between the arm members at a predetermined distance from the axle, and one end of the auxiliary arm is connected to the center of the axle, and the other end of the auxiliary arm is swingably connected to the center of the auxiliary bar. Suspension structure characterized by. 3. A suspension structure in which each one end of a pair of trailing arm members is connected to an axle via a bush, and the other ends of these trailing arm members are pivotally supported by a vehicle body frame. , An auxiliary bar is laid between the intermediate portions of the trailing arm member at a predetermined distance from the axle, and a bush is interposed between the auxiliary bar and the support portion of the trailing arm member, A suspension structure characterized in that the other end of an auxiliary arm having one end connected to the central part is swingably connected to the central part of the auxiliary bar.