JPH11334332A - Front suspension - Google Patents

Abstract

(57) [Summary] Even when a suspension arm is connected to a sub-frame via a plurality of connecting parts, it is not necessary to provide a large number of brackets dedicated to the sub-frame, and the suspension has a simple structure. Ensure that the arm can be properly connected to the subframe. A sub-frame (2) mounted on a body frame (1) of a vehicle, and a suspension arm (3) for supporting a front wheel, the base end of which is connected to the sub-frame (2) via a plurality of connecting portions (5A, 5B). And at least one of the plurality of connecting portions 5A and 5B is fastened together with the sub-frame 2 to the body frame 1 together with the sub-frame 2 by means of bolts 9. The structure is made.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a front suspension for an automobile, and more particularly, to a front suspension having a structure using a subframe.

[0002]

2. Description of the Related Art Conventionally, as an example of this type of front suspension, there is one disclosed in, for example, Japanese Utility Model Laid-Open No. 6-201110. The one described in the publication has a structure in which a suspension arm for supporting a front wheel is assembled to a subframe as a suspension member attached to a body frame. The suspension arm is generally called an L-shaped lower arm,
The bifurcated base end is rotatably connected to the subframe via two connecting portions.

In the front suspension having the above structure,
Unlike the structure in which the suspension arm is directly mounted on the body frame of the automobile, the engine or other devices can be mounted on the subframe, and the devices can be mounted with high accuracy. Also, if the sub-frame is attached to the body frame via a rubber bush or the like, vibrations from the road surface or the engine can be hardly transmitted to the body. Furthermore, since the suspension arm is connected to the subframe via the two connection portions, the suspension arm is compared with a suspension using a suspension arm having only one connection portion called a so-called I-type lower arm. It is also possible to reduce the compliance of the entire suspension and stabilize the direction of the front wheels without increasing the manufacturing cost.

[0004]

However, the conventional front suspension has the following disadvantages.

That is, conventionally, the attachment of the sub-frame to the body frame and the connection of the suspension arm to the sub-frame are performed by completely different means. In addition, two bracket portions are provided on the subframe for connecting the two portions at the base end of the suspension arm. For this reason, conventionally, the number of brackets provided on the sub-frame has increased, and the structure of the sub-frame has been complicated by that much, and its manufacture has been complicated.

Further, it is necessary to manufacture the two bracket portions so as to have an appropriate strength by being formed to a certain size. However, there are cases where various parts and devices other than the suspension arm are mounted on the subframe, and there is a certain limit to increasing the size of the subframe from the viewpoint of reducing the weight of the vehicle, In some cases, it was difficult to secure a space for providing the two brackets in the subframe. In particular, in this type of front suspension, a suspension arm is generally connected to a portion of the subframe near the rear of the vehicle. In such a case, the rear portion of the subframe and the body frame are attached. The bracket portion for supporting the suspension arm is considerably close to the mounting portion for the vehicle, making it more difficult to properly provide the bracket portion on the subframe.

The present invention has been devised under such circumstances, and even when the suspension arm is connected to the subframe via a plurality of connecting portions, the suspension frame is dedicated to the subframe. It is an object of the present invention to eliminate the necessity of providing a large number of bracket portions and to enable the suspension arm to be appropriately connected to the subframe with a simple structure.

[0008]

DISCLOSURE OF THE INVENTION In order to solve the above problems, the present invention employs the following technical means.

The present invention includes a subframe mounted on a body frame of a vehicle, and a front wheel supporting suspension arm having a base end connected to the subframe via a plurality of connecting portions. Wherein at least one of the plurality of connecting portions has a structure in which a base end of the suspension arm is jointly fastened to the body frame together with the subframe with a bolt. It is characterized by.

According to the present invention, the following effects can be obtained.

First, according to the present invention, in the connection portion where the suspension arm and the subframe are jointly fastened to the body frame with bolts, the attachment of the subframe to the body frame and the connection of the suspension arm to the subframe are collectively performed. Can be done. Therefore, in the present invention, the structure can be made quite rational as compared with the conventional one in which the attachment of the sub-frame to the body frame and the connection of the suspension arm to the sub-frame are performed completely separately, and Can be simplified. Further, the number of parts can be reduced by sharing the bolts.
As a result, manufacturing costs can be reduced.

Secondly, in the present invention, it is not necessary to provide a suspension arm supporting bracket on the sub-frame for the joint where the suspension arm and the sub-frame are jointly fastened to the body frame by bolts. Therefore, in the present invention, the number of the brackets for supporting the suspension arms, which must be provided on the subframe, is reduced as compared with the conventional case, and the structure of the subframe is simplified by that much, so that the manufacturing cost can be further reduced. I can do it. Further, the weight can be reduced. In addition, it is possible to solve the conventional inconvenience that it is difficult to secure a space for providing the bracket portion on the subframe.

Third, in the present invention, since the base end of the suspension arm can be supported by the rigid body frame, the base end of the suspension arm can be provided without increasing the rigidity of the sub-frame so much. Also, the effect that the supporting strength can be secured can be obtained.

Other features and advantages of the present invention will become more apparent from the following description of embodiments of the present invention.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be specifically described below with reference to the drawings.

FIG. 1 is an explanatory view showing a schematic side view schematic structure of a front suspension according to the present invention and an enlarged sectional structure of a main part thereof. FIG. 2 is a schematic plan view of a main part of the front suspension shown in FIG. In each of the drawings after FIG. 1, an arrow Fr indicates the front of the vehicle, an arrow Up indicates an upper side in the vehicle height direction, and an arrow Ou indicates an outer side in the vehicle width direction.

Referring to FIG. 1, a front suspension A includes a subframe 2 attached to a lower surface of a front side member 1 of an automobile, and a suspension arm 3 connected to the subframe 2. I have. The front side member 1 and a protrusion 1a provided on the lower surface of the front side member 1.
Is a member corresponding to an example of the body frame in the present invention. The front side member 1 is disposed on a vehicle width direction side of a front portion of the vehicle and extends in the vehicle front-rear direction.

The sub-frame 2 is formed in a hollow frame shape in plan view by, for example, appropriately welding a member formed by pressing a metal plate. The cross-sectional shape of each part is also hollow to reduce the weight. It is formed in a shape. At the front and rear sides of a side portion 2a extending in the vehicle front-rear direction located on the vehicle width direction side of the sub-frame 2, mounting portions 4a and 4b for mounting the sub-frame 2 to the front side member 1 are provided. Is provided.

The mounting portion 4a has a hole 20a provided in the front portion of the sub-frame 2 and a rubber bush 7A, as shown in an enlarged sectional view of a portion B in FIG. Part of the sub-frame 2 is inserted, and the rubber sandwiches the front part of the sub-frame 2 from the upper and lower sides. The rubber bush 7A is attached to the lower surface of the front side member 1 by tightening a bolt 41 inserted into the inner cylinder and a nut 42 screwed thereto. On the other hand, the mounting portion 4b has a structure in which the rear portion of the sub-frame 2 is fastened together with the suspension arm 3 to the protruding portion 1a of the front side member 1 by bolts 9. The front suspension A of the present embodiment has the greatest feature in this point, and this structure will be described later. The sub-frame 2 is used not only as a component of the front suspension A but also appropriately for supporting a power plant such as an engine and a steering gear box. For this reason, brackets (not shown) for supporting these devices and components are provided at appropriate places on the subframe 2. However, the subframe referred to in the present invention is
It is not always necessary to be used also for supporting the engine and other devices, and a type that can be attached to the body frame only to support the suspension arm may be used.

The suspension arm 3 is an arm extending outward from the side portion 2a of the subframe 2 in the vehicle width direction, as shown in FIG. Can be A stabilizer or the like (not shown) is connected to a position near the tip of the suspension arm 3. The base end of the suspension arm 3 has a bifurcated form, so that a first base end 32a and a second base end 32b are provided at an interval in the vehicle longitudinal direction. Have been. The first base end 32a and the second base end 32b are rotatably connected to the sub-frame 2 via the first connection 5A and the second connection 5B.

The first connecting portion 5A has a rubber bush 6 attached to a first base end 32a of the suspension arm 3 disposed between a pair of bracket pieces 22 provided on the sub-frame 2. This is a portion in which the rubber bush 6 is supported by the pair of bracket pieces 22, 22 by bolts 23 inserted through the inner cylinder. The bolt 23 has a posture in which its axis extends in a substantially horizontal direction. Therefore, the suspension arm 3 is connected to the first connecting portion 5.
It can swing in the vehicle height direction with the A bolt 23 as one fulcrum.

The second connecting portion 5B has a structure in which the second connecting portion 5B is integrated with the mounting portion 4b at the rear of the sub-frame 2. More specifically, as clearly shown in the enlarged cross-sectional view of the portion C in FIG. 1, the mounting portion 4b is formed with a hole provided in the sub-frame 2 similarly to the front mounting portion 4a described above. The inner cylinder of the rubber bush 7B and a part of the rubber are inserted into the portion 20b, and the rubber sandwiches the sub-frame 2 from above and below. The rubber bush 7B is attached to the protruding portion 1a of the front side member 1 by tightening a bolt 9 inserted into the inner cylinder of the rubber bush 7B and a nut 9a screwed thereto. .

On the other hand, the second connecting portion 5B has a structure in which a rubber bush 8 fixed and attached to the second base end 32b of the suspension arm 3 is disposed below the rubber bush 7B. However, the bolt 9 is inserted through the inner cylinder of the rubber bush 8.
The rubber bush 8 is fastened together with the rubber bush 7B of the sub-frame 2 to the projecting portion 1a of the front side member 1 by tightening the nut 9a and the nut 9a. Although the axis of the rubber bush 8 extends in a substantially vertical direction, the outer cylinder of the rubber bush 8 can move relative to the inner cylinder in various directions within a certain range. Can swing in the vehicle height direction using the second connecting portion 5B as another fulcrum.

In the front suspension A, the second connecting portion 5B and the mounting portion 4b are substantially integrated, so that the rubber bush 7B of the sub-frame 2 can be mounted on the projection 1a of the front side member 1. And the connection of the rubber bush 8 of the suspension arm 3 to the rear part of the sub-frame 2 is a set of bolts and nuts 9,9.
This is done collectively by tightening a. Therefore, the entire structure including the structure for attaching the rear portion of the subframe 2 to the protrusion 1a of the front side member 1 and the structure for connecting the base end of the suspension arm 3 to the subframe 2 is significantly simplified. Is done. In addition, the space required for mounting and connecting them can be reduced, and it is easy to secure the space required for mounting and connecting these components.

In particular, the rubber bush 8 of the suspension arm 3 has a structure in which the rubber bush 8 is bolted in a state of being overlapped below the rubber bush 7B of the sub-frame 2, and a special structure for supporting the rubber bush 8 is provided. There is no need to provide a special bracket portion on the subframe 2. Therefore, the structure and weight of the subframe 2 can be simplified. Further, since the bolts and nuts 9 and 9a are shared, the number of parts required for mounting and connecting the above components is reduced, and the structure is further simplified and the weight is reduced.

Further, in the front suspension A, the second base end 32b of the suspension arm 3 is substantially supported by the protruding portion 1a of the front side member 1 having high rigidity. Therefore, it is preferable to increase the supporting strength of the second base end 32b of the suspension arm 3.

FIGS. 3 and 4 are cross-sectional views of main parts showing other examples of the front suspension according to the present invention. In these drawings, the same parts as those in the previous embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

In the structure shown in FIG. 3, the second base end portion 32b of the suspension arm 3 and the rear portion of the subframe 2
While one rubber bush 8A is attached,
The rubber bush 8A is attached to the protrusion 1a of the front side member 1 by a bolt 9. The rubber bush 8A is the same as the rubber bush 7 described in FIG.
It has a structure similar to that in which B and the rubber bush 8 are integrated. According to such a configuration, the number of rubber bushes can be reduced, and the number of parts can be further reduced.

In the structure shown in FIG. 4, the rear portion of the sub-frame 2 is attached to the protrusion 1a of the front side member 1 without the interposition of a rubber bush, and an auxiliary member made entirely of a hard material is interposed between them. 8B is provided interposed. Below the auxiliary member 8B, a rubber bush 8 attached to the second base end 32b of the suspension arm 3 is arranged in an overlapping manner, and the rubber bush 8 and the auxiliary member 8B are shared by bolts 9. Has been tightened. According to such a configuration, since the subframe 2 can be rigidly connected to the front side member 1, it is suitable for reducing the compliance of the entire front suspension and improving the running stability of a so-called high-power vehicle. Becomes On the other hand, according to the structure in which the rubber bush 7B is interposed between the sub-frame 2 and the protrusion 1a of the front side member 1 in the embodiment shown in FIG. 1, the rubber bush 7B serves as an insulator for suppressing vibration. This is suitable for improving the riding comfort of the vehicle during middle / low speed running.

Needless to say, the specific configuration of each part of the front suspension according to the present invention is not limited to the above-described embodiment, and various design changes can be made.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a schematic side view structure of a front suspension according to the present invention and an enlarged sectional structure of a main part thereof.

FIG. 2 is a schematic plan view of a main part of the front suspension shown in FIG.

FIG. 3 is a sectional view of a main part showing another example of the front suspension according to the present invention.

FIG. 4 is a sectional view of a main part showing another example of the front suspension according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Front side member (body frame) 1a Projection part (body frame) 2 Subframe 3 Suspension arm 5A First connection part 5B Second connection part 9 Bolt 32a First base end 32b Second base end A Front suspension W Front wheel

Claims (1)

[Claims] 1. A sub-frame mounted on a body frame of a vehicle, and a front-wheel supporting suspension arm having a base end connected to the sub-frame via a plurality of connecting portions. A front suspension, wherein at least one of the plurality of connecting portions has a structure in which a base end of the suspension arm is jointly fastened to the body frame together with the subframe with a bolt. And the front suspension.