JP2001130233A - Strut type suspension - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a strut type suspension capable of realizing a light weight and a high rigidity of a damper outer cylinder and provided with the damper outer cylinder having a simple and cheap constitution. SOLUTION: The strut type suspension for vehicle is provided with a damper to which an axle support member is bonded and which supports a spring. A damper outer cylinder 1 is provided with a light weighed portion 1b supporting a spring; a high rigid portion 1a bonded to the axle support member; and a transition portion 1c which connects the light weighed portion 1b and the high rigid portion 1a and of which shape is gently varied between them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strut type suspension for a vehicle.

[0002]

2. Description of the Related Art As a conventional strut type suspension, for example, there is a strut type suspension as shown in FIG. 3. In such a strut type suspension, a lower portion of a damper outer cylinder 1 has an axle support member (here, a knuckle). The axle support member 4 is inserted into the through hole of the spindle 4 and is coupled thereto, and the axle is supported integrally with the axle. And the damper outer cylinder part 1 supports the coil spring 3 via the spring support 2 attached to the upper part.

In such a suspension, since an external force acts on the damper outer cylinder portion 1 from the wheels via the axle support member 4, the damper outer cylinder portion 1 is required to have camber rigidity and lateral rigidity. For this reason, the damper outer tube portion 1 has conventionally generally used a steel pipe material, but in recent years, for the purpose of reducing the weight, a damper outer tube portion having a uniform thickness has been used,
A damper outer cylinder using an aluminum material instead of a steel pipe material has been proposed.

[0004]

However, in the above-described damper outer cylinder portion having a uniform thickness and an aluminum damper outer cylinder portion, a conventional damper outer cylinder portion is not provided. There is a problem that rigidity is reduced.

Therefore, it is conceivable to increase the wall thickness of the aluminum damper outer cylinder to secure rigidity.
However, in order to support the axle support member 4 with high rigidity at the lower portion of the damper outer cylinder portion 1, the thickness must be increased with respect to the lower portion, so that the weight reduction is required. There is a problem that it becomes smaller and the cost effectiveness becomes worse.

[0006] In the strut suspension,
As shown in FIG. 2, there is a place where the gap between the damper outer tube portion 1 and the tire T is narrow, and at least a minimum gap is secured to prevent the contact between the damper outer tube portion 1 and the tire T. Must. In addition, if the gap can be made as large as possible, it becomes possible to mount a large-sized tire. Therefore, the effect of increasing such a gap is great. However, in the conventional damper outer cylinder portion, there is a need to secure the rigidity of the damper outer cylinder portion, so that there is a restriction in layout in order to secure a minimum gap,
Also, it was difficult to allow more room for the gap.

[0007] Therefore, in the above-described conventional damper outer cylinder portion, it is possible to reduce the weight and increase the rigidity of the damper outer cylinder portion, and to allow a clearance between the damper outer cylinder portion and the tire. It has been difficult to provide a strut suspension having a simple and inexpensive damper outer cylinder.

By the way, in the lower part of the damper outer cylinder part 1 which is a connection part with the axle support member 4, since a force is directly applied from the axle support member 4, a concentrated load is applied. However, in contrast to this, in the present invention, the load concentrated on the upper part of the damper outer cylinder part 1 supporting the coil spring 3 does not occur as much as the lower part of the damper outer cylinder part 1. Headlined.

An object of the present invention is to provide a strut type suspension which advantageously solves the above-mentioned problem in view of the above-mentioned knowledge of the present inventor.

[0010]

The strut type suspension according to the first aspect of the present invention is characterized in that:
An axle support member is coupled and supports a spring, in a vehicle strut type suspension including a damper, a damper outer cylinder portion has a lightweight portion supporting the spring, a high rigidity portion coupled to the axle support member, It is characterized by comprising a transition portion that connects the lightweight portion and the high-rigidity portion, and the shape of the transition portion changes smoothly between them.

In the strut type suspension according to the present invention, the outer cylinder portion of the damper supports the spring at the lightweight portion, is coupled to the axle support member at the high rigidity portion, and further has the lightweight portion and the high rigidity at the transition portion. The parts are connected and the shape is gently changed between them.

Therefore, according to the strut suspension of the present invention, even if the high-rigidity portion and the light-weight portion have different outer diameters and inner diameters, the transition portion is formed between the high-rigidity portion and the lighter weight portion. They can be connected by changing the shape gently. For this reason, it is assumed that sufficient strength is obtained in the high-rigidity portion, and in the light-weight portion separated from the high-rigidity portion, for example, the outer diameter of the light-weight portion is reduced and the thickness of the lightweight portion is reduced. Therefore, it is possible to easily reduce the weight of the outer cylinder portion of the damper.

Therefore, according to the strut type suspension of the present invention, even if the same steel pipe material as the conventional one is used,
It is possible to easily and inexpensively manufacture a high-rigidity damper outer cylinder that can be reduced in weight.

The strut suspension according to the second aspect of the invention is characterized in that the outer diameter of the lightweight portion is smaller than that of the higher rigidity portion. By doing so, in addition to obtaining the same effect as the above-described invention, the gap between the damper outer cylinder portion and the tire can be easily widened. For example, a tire of a larger size is mounted on the vehicle. It is also possible to do.

Further, in the strut type suspension according to the third aspect of the present invention, the light-weight portion is more than the high-rigidity portion.
It is characterized by being thin. This makes it possible to easily reduce the weight of the outer cylinder portion of the damper.

Further, in the strut suspension according to the fourth aspect of the present invention, the transition portion is gradually reduced in outer diameter from the high-rigidity portion to the light-weight portion. In this way, it is possible to easily prevent stress concentration at a portion connecting the high-rigidity portion and the light-weight portion having a small outer diameter, and to easily integrate the damper outer cylinder portion integrally. Can be processed.

According to a fifth aspect of the present invention, in the strut type suspension, the transition portion is gradually reduced in thickness from the high-rigidity portion to the light-weight portion. This makes it possible to smoothly connect the lightweight portion and the high-rigidity portion by the transition portion, and to easily reduce the weight of the transition portion.

[0018]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG.
FIG. 2 is a front view, partially in section, of a damper outer cylinder portion of the strut suspension according to one embodiment of the present invention.
FIG. 1 is a front view showing a cross section of a part of a strut suspension of this embodiment in a state where wheels are mounted. In the drawing, the same parts as those in the conventional example are denoted by the same reference numerals.

The strut type suspension of this embodiment has the same structure as the conventional suspension shown in FIG. 3, but in this embodiment, in particular, FIG. 1 and FIG.
As shown in FIG. 5, the damper outer cylinder portion 1 has a high-rigidity portion 1a at a lower portion, a light-weight portion 1b at an upper portion, and a transition portion 1c connecting them. The portion 1 is a cylinder whose outer diameter and thickness are both set to sufficiently support the external force from the axle support member 4, and the lighter portion 1b is smaller in both outer diameter and thickness than the high-rigidity portion 1a. The transition portion 1c has a truncated cone shape in which both the outer diameter and the wall thickness are smoothly changed from the high-rigidity portion 1a to the lightweight portion 1b.

As shown in FIG. 2, the damper outer cylindrical portion 1 offsets and supports the coil spring 3 via a spring support 2 attached to the lightweight portion 1b, as shown in FIG. The high-rigidity portion 1a is inserted into a through hole 4a of an axle support member (knuckle spindle in this embodiment) 4 and directly connected to the axle support member 4. The axle support member 4 And support the axle 5.

When the damper outer cylinder 1 is formed of, for example, the same steel pipe material as in the prior art, a shape corresponding to the inner peripheral surface of the damper outer cylinder 1 is formed on a base tube made of the steel pipe material. A mandrel having an outer peripheral surface of the dimensions is inserted, and while the roll dies forming a pair facing each other are rotated around their respective axis centers, the element into which the mandrel is inserted is formed between the outer peripheral forming portions of the roll dies. By inserting a tube from the end where the high rigidity portion 1a is formed and cold drawing the raw tube, the above-described high rigidity portion 1a and lightweight portion 1b are formed.
And the transition portion 1c can be integrally formed.

Therefore, according to the strut type suspension of this embodiment, it is possible to easily and inexpensively manufacture a high-rigidity damper outer cylinder which can be reduced in weight even if the same steel pipe material as the conventional one is used. .

Further, according to the damper outer cylinder portion 1 of the strut type suspension of this embodiment, the transition portion 1c forms the high rigid portion 1a and the lightweight portion 1b having different outer diameters and inner diameters from each other. Since they are gently changed and they are connected, sufficient strength can be obtained with the high-rigidity portion 1a, and the light-weight portion 1b whose outer diameter and wall thickness are both smaller than the high-rigidity portion 1a has The weight of the tubular portion 1 can be easily reduced.

According to this embodiment, the outer diameter of the light-weight portion 1b is made smaller than the outer diameter of the high-rigidity portion 1a, and as shown in FIG. Clearance C with tire T
Can be easily widened, and the gap C can have a margin. For this reason, for example, it is possible to mount a tire having a larger size on the vehicle.

Furthermore, according to this embodiment, the transition portion 1c of the frusto-conical shape gradually decreases in outer diameter from the high rigidity portion 1a to the light weight portion 1b, so that the high rigidity portion 1a In addition to this, it is possible to easily prevent stress concentration at a portion connecting the lightweight portion 1b having an outer diameter with a small diameter, and
As described above, the damper outer cylinder portion 1 can be integrally and easily processed.

In addition, according to this embodiment, the transition section 1c
However, since the thickness is gradually reduced from the high-rigidity portion 1a toward the lightweight portion 1b, the transition portion 1c smoothly connects the light-weight portion 1b and the high-rigidity portion 1a and reduces the weight of the transition portion 1c. It can be easily achieved.

Although the present invention has been described with reference to the illustrated examples, the present invention is not limited to the above-described examples. For example, in the above-described embodiment, the axle support member 4 fixedly supports the axle 5 for a driven wheel. Although the knuckle spindle is used, the invention is not limited thereto, and a knuckle spindle that rotatably supports the axle 5 for driving wheels may be used. Further, the damper outer cylinder 1 is not limited to the above-described manufacturing method, and may be manufactured by another method, for example, by extruding a base tube through a die hole or by drawing.
Further, the shape of the damper outer cylinder portion 1 is not limited to the above-mentioned one. For example, as a truncated conical shape in which the outer diameter and the inner diameter are continuously reduced from the transition portion 1c to the lightweight portion 1b, the wall thickness is also reduced. The thickness may be constant or the thickness may be constant. Then, the material of the damper outer cylinder portion 1 may be lighter, for example, an aluminum alloy material or a high-rigidity resin.
In that case, a fiber reinforced metal or a fiber reinforced resin may be used.

[Brief description of the drawings]

FIG. 1 is a front view, partially in section, of a damper outer cylinder part of a strut type suspension according to one embodiment of the present invention.

FIG. 2 is a front view showing the strut suspension of the embodiment in a partial cross section in a state where wheels are mounted.

FIG. 3 is a perspective view illustrating the whole of a conventional strut type suspension.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Damper outer cylinder part 1a High rigidity part 1b Light weight part 1c Transition part 2 Spring support 3 Coil spring 4 Axle support member 4a Through hole 5 Axle T Tire C Clearance

Claims (5)

[Claims] 1. A vehicle strut type suspension having a damper for supporting a spring coupled with an axle support member, wherein an outer cylindrical portion of the damper includes: a lightweight portion for supporting the spring; A strut-type suspension comprising: a high-rigidity portion to be joined; and a transition portion that connects the light-weight portion and the high-rigidity portion and that has a shape that changes smoothly between them. 2. The strut-type suspension according to claim 1, wherein the light-weight portion has a smaller outer diameter than the high-rigidity portion. 3. The strut type suspension according to claim 1, wherein the light weight portion is thinner than the high rigidity portion. 4. The strut suspension according to claim 2, wherein the transition portion has an outer diameter gradually reduced from the high-rigidity portion toward the light-weight portion. 5. The strut-type suspension according to claim 3, wherein the transition portion has a gradually decreasing thickness from the high-rigidity portion to the light-weight portion.