Abstract:
A suspension arm for supporting an automobile wheel is joined with a gusset by two bushing means. The gusset is fixed to an automobile body to hold the suspension arm to the automobile body. Each of the bushing means is placed coaxially with the other in the fore and aft direction of the automobile and allows the suspension arm to turn up and down. Preferably, each of the bushing means comprises a bushing and a pin inserted into the bushing.

Description:
This is a continuation of U.S. Patent application Ser. No. 331,071, filed Dec. 16, 1981, now abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates generally to a suspension arm assembly for supporting an automobile wheel, and more specifically to such a suspension arm assembly having an improved construction for mounting a suspension arm on an automobile body. 
     A suspension arm or a control arm holds an automobile wheel to a mounting portion of an automobile body, and transmits sidewise force from the wheel to the body. Accordingly, the mounting portion of the automobile body must be constructed to be sufficiently rigid. However, such a requirement brings about several disadvantages, such as an increase of the total weight of an automobile and deterioration of production efficiency. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a suspension arm assembly which is arranged to improve a mounting construction for mounting a suspension arm on an automobile body. 
     According to the present invention, a suspension arm assembly for supporting a front wheel of a front engine front wheel drive automobile mainly comprises a suspension arm for supporting the front wheel, and a gusset to be fastened to an automobile body. The suspension arm assembly of the present invention further comprises first and second bushing means disposed between the suspension arm and the gusset for swingably joining the suspension arm with the gusset. Each of the bushing means is placed coaxially with the other along the fore and aft direction of the automobile. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1A is a perspective view showing a conventional type mounting portion of an automobile body; 
     FIG. 1B is a perspective view of a portion of FIG. 1A viewed from the direction of the arrow B of FIG. 1A; 
     FIG. 2 is a plan view showing one embodiment of the present invention; 
     FIG. 3 is a front view showing the suspension arm and the gusset of FIG. 2 mounted on a vehicle body; 
     FIG. 4 is a side view showing the vehicle body, the gusset and the bushing shown in FIG. 3. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring first to FIGS. 1A and 1B, a brief reference will be made to one example of the conventional structure for mounting a suspension arm on the automobile body. A side member 1 is made of a heavy plate and fastened to the automobile body 2 by arc welding. A brace 4 is welded between the side member 1 and a dash crossmember for reinforcement against sidewise force. There are further provided a mounting portion 5 for mounting a suspension arm and a hole 6 for a steering linkage. 
     In such a conventional construction, however, the side member 1 is placed high so as not to offer obstruction to a drive shaft, and the suspension arm mounting portion 5 is disposed under the side member 1. Accordingly, in order to provide enough rigidity against sidewise force exerted on the mounting portion 5 from the wheel, it is necessary to make the side member 1 of a heavy plate and to reinforce the structure with the brace 4 by arc welding. Thus, such a conventional mounting construction has disadvantages in the production efficiency and the fuel economy of an automobile because of increases in the number of assembly processes and the total weight of the automobile. Especially, use of arc welding in automobile assembly processes is obstructive to automatization of manufacturing. Furthermore, because the suspension arm is generally mounted on the mounting portion in a full rebound state in view of working efficiency, a bushing interposed between the suspension arm and the mounting portion is always subjected to one sided torsion during car running, and this deteriorates the durability of the bushing. 
     In view of the above description, reference is now made to FIGS. 2, 3 and 4, wherein an embodiment of the present invention is shown. 
     In this embodiment, the present invention is applied to a strut type front suspension. A suspension arm or a control arm 7 has a first pin 8 which is welded thereto and has an axis extending in the fore and aft direction of the automobile. A first bushing 9 is attached to the pin 8 and fastened by a nut 10. There is provided a gusset 11, to which the bushing 9 is fixed with a mounting bracket 12 by tightening a bolt 14 to a nut 13 welded to the gusset 11. 
     The gusset 11 has a second pin 15 which is welded thereto and has an axis extending in the fore and aft direction. The pin 15 is inserted through a second bushing 16 which is forcibly inserted into a position of the suspension arm 7 and fastened by a nut 17. Thus, the pins 8 and 15, and the bushings 9 and 16 are all oriented coaxially along the fore and aft direction, and by these pins and bushings, the suspension arm 7 and the gusset 11 are connected together. The gusset 11 is fixed to a dash crossmember 18a of a vehicle body 18 with bolts and nuts 19, 20, 21, 22, 23 and 24. 
     The suspension arm 7 supports a vehicle wheel 26 through a ball joint 25. The vehicle wheel 26 is further supported by a strut assembly 27 disposed between the vehicle body 18 and the vehicle wheel 26. A drive shaft 28 connects a final gear with the wheel 26 through constant velocity universal joints 29 and 30. Reference numerals 28a and 28b denote the positions of the drive shaft 28, respectively in a full jounce state and a full rebound state. Reference numeral 6 denotes a hole through which a steering linkage is inserted. 
     The operations of this embodiment are as follows: First, the suspension arm 7 is joined with the gusset 11 in the following manner. Preliminarily, the pins 8 and 15 are welded, respectively, to the suspension arm 7 and the gusset 11. The bushing 16 is forcibly inserted in a position of the suspension arm 7, and the bushing 9 is attached to the pin 8 and fastened by the nut 10. After such a preparatory arrangement, the suspension arm 7 is joined with the gusset 11 by inserting the pin 15 of the gusset 11 into the bushing 16 and at the same time inserting the bushing 9 attached to the pin 8 of the suspension arm 7 between the gusset 11 and the mounting bracket 12. Then, the angle between the suspension arm 7 and the gusset 11 is set at the most suitable angle for the bushings 9 and 16 to work. Usually, the most suitable angle is a neutral angle between the full jounce state and the full rebound state. After the best angle is selected, the bushing 16 is fastened to the pin 15 by tightening the nut 17, and the bushing 9 is fastened to the gusset 11 by tightening the bolt 14 and the nut 13 and fastening the mounting bracket 12 to the gusset 11. In some circumstances, it is convenient to tighten the nuts 13 and 17 temporarily at this stage and fully tighten them later. 
     Secondly, the suspension arm 7 joined with the gusset 11, the strut assembly 27, and the drive shaft 28 are connected to the vehicle wheel 26, which has, at this stage, neither a road wheel 26a nor a tire 26b. Then, the gusset 11 and the top end of the strut assembly 27 are fixed, respectively, to the vehicle body 18, while the end of the drive shaft 28 is connected to the final gear. Fixing of the gusset 11 is done by the bolts and nuts 19, 20, 21, 22, 23 and 24. After that, the road wheel 26a with the tire 26b is mounted on a front hub 26c. 
     Thus, the vehicle wheel 26 is supported on the vehicle body by the suspension arm 7 and the gusset 11 on the one hand, and by the strut assembly 27 on the other hand. The suspension arm 7 and the gusset 11 give a support to the wheel in the fore and aft direction and the right and left direction, and the strut assembly 27 gives a support in the up and down direction. Torsional movement of the bushings 9 and 16 allow the suspension arm 7 to swing up and down as the vehicle wheel 26 moves up and down. Sidewise force exerted on the vehicle wheel 26 is received by the gusset 11 through the bushings 9 and 16 and the pins 8 and 15. 
     Thus, according to the present invention, the bushings 9, 16 interposed between the gusset 11 and the suspension arm 7 can be fastened while the suspension arm is held at the most advantageous angle for the durability of the bushings. Furthermore, the gusset 11 receives sidewise force from the vehicle wheel and transmits it to the vehicle body, so that sidewise force is not applied directly to the vehicle body but dispersed by the gusset. Accordingly, the suspension arm assembly of the present invention does not requires so high rigidity of the suspension arm mounting portion of the vehicle body, and eliminates the necessity of the brace which must be joined by undesirable arc welding and causes obstruction to other parts of the automobile, so that the production efficiency is improved and the mounting construction is simplified.