JPH11115807A - Vehicle body front part structure for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the grounding of a steering gear case at the time of travel on a bad road, etc., even without providing an under cover, and also obtain a low cost, light weight, compactness, and moreover an adequate (small) toe angle change also a smooth steering feeling. SOLUTION: This vehicle body front part structure is constituted so as to fit a suspension arm (lower control arm 16), and a steering gear case 11 (pinion case 11a) to a suspension frame 3, and also arrange at least part of the steering case 11 (e.g. the pinion case 11a) in the lower part than the suspension frame 3. In this case, a lower part protruded part 21, being protruded directed to a lower part side and having a tilted surface 21a having a shape obliquely descending with directing the vehicle body rear part, is provided on the bottom surface part 20 of the suspension frame 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a front structure of a vehicle body of an automobile, and more particularly to a suspension frame structure of a strut type suspension provided at a front portion of the body of an automobile.

[0002]

2. Description of the Related Art When the type of a suspension provided at the front of a vehicle body of an automobile is a double wishbone type, the steering gear case is attached to a cross member or a suspension frame of the vehicle body, which is a mounting portion of the steering gear case. Even if the tire is disposed at a higher position, it is possible to obtain an appropriate change in the toe angle of the tire. For example,
As shown in FIG. 6, a steering gear case (pinion case) 33 is mounted on an upper surface of a suspension frame 30 fixed to a vehicle body frame via a mounting bracket 31 and a mounting bracket 32, so that the steering gear case 33 is positioned higher than the suspension frame 30. , It is possible to obtain a suitable change in the toe angle of the tire.

On the other hand, when the type of the suspension is a strut type, an appropriate tire is required unless the height of the arrangement of the steering gear case is reduced as much as possible and the length of the tie rod with respect to the lower control arm is increased. Cannot be obtained. For this reason,
In a car with strut suspension, FIG.
As shown in FIG. 7, a steering gear case 33 is mounted on the rear surface of the suspension frame 30 via a mounting member 34, and a lower portion of the steering gear case 33 is arranged below the suspension frame 30. However, if the steering gear case 33 is arranged at a lower position in the case of a layout in which the steering gear case 33 is arranged ahead of the front wheels, there is a possibility that problems such as the steering gear case 33 contacting the road surface when traveling on a rough road may occur. For this reason, in the prior art, as shown in FIG.
The under guard 36 is arranged between the vehicle and the cross member 35 of the vehicle body frame.

[0004]

However, in the above-described conventional vehicle body front structure, a separate member, the under cover 36, is provided to protect the steering gear case 33.
Therefore, there is a problem that the number of parts and the number of assembling steps are increased, and the weight of the vehicle body is increased. In order to make the tie rod as long as possible, it is necessary to move the steering pinion 37 (see FIGS. 6 and 7) to a position inside the vehicle body (center side of the vehicle body). There is a problem that the joint angle increases, the steering force fluctuates greatly, and the steering feeling deteriorates.

On the other hand, in order to protect the steering gear case 33, it is conceivable to move the steering rack shaft upward to arrange the steering gear case at a high position. In this case, however, it is necessary to appropriately change the toe angle. Need to increase the length of the tie rod
Accordingly, the steering rack shaft (not shown) becomes relatively short, and a required steering angle cannot be obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a steering gear case which can be mounted on a rough road even when the steering gear case is disposed at a low position without an under cover. Front structure of a vehicle equipped with a steering system capable of preventing a vehicle from coming into contact with a road surface, and having a low-cost, lightweight, compact, and appropriate (small) toe angle change and a smooth steering feeling. Is to do.

[0007]

In order to achieve the above object, according to the present invention, a suspension arm and a steering gear case are mounted on a suspension frame, and at least a part of the steering gear case is disposed below the suspension frame. In the vehicle body front structure described above, a lower protruding portion is provided on the bottom surface of the suspension frame, the lower protruding portion having an inclined surface that protrudes downward and is inclined downward toward the rear of the vehicle body. In the present invention, the lowermost end of the downward projecting portion is located at a position lower than the lowermost end of the steering gear case. In the present invention, a plurality of the lower protruding portions may be formed on the bottom surface of the suspension frame, and at least one of the plurality of lower protruding portions may be disposed on the vehicle body front side with respect to the steering gear case. I have to.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

FIGS. 1 and 2 show a vehicle body front structure of a four-wheeled vehicle 1 having a strut type front suspension. In these figures, reference numeral 2 denotes a cross member constituting a vehicle body frame, and reference numeral 3 denotes a cross member. A suspension frame 4 fixed to the vehicle body frame at a position in front of the member 2 and substantially parallel to the member 2 transmits steering operation force of the steering handle 5 to the front wheel 6 to steer the front wheel 6. Mechanism.

As shown in FIG. 2, the steering mechanism 4 includes a steering shaft 7 connected to a steering handle 5, a connecting shaft 9 connected to the steering shaft 7 via a universal joint 8a, Steering pinion 10 connected to connecting shaft 9 via universal joint 8b
A steering rack shaft (not shown) in a steering gear case 11 meshed with the steering pinion 10, a tie rod 12 connected to the steering rack shaft (steering gear), and a knuckle 13 attached to the front wheel 6. , And the turning operation force of the steering handle 5 is transmitted to the front wheel 6 via these members in order. Note that the steering gear case 11 is located in front of the cross member 2 and behind the suspension frame 3.
The suspension frame 3 is arranged substantially in parallel with the suspension frame 3. A bush 15 is attached to the lower surface of both ends of the suspension frame 3 via a bracket 14 (see FIG. 3), and a lower control arm 16 is rotatably installed between the bush 15 and the knuckle 13. (See FIGS. 1 to 4).

The suspension frame 3 in the present embodiment comprises, for example, an upper half 3a and a lower half 3b which are press-formed into two parts, as shown in FIG. 3a and lower half 3b in FIG.
The suspension frame 3 having a closed cross-sectional shape is configured by combining the suspension frames with each other as shown in FIG. Then, a steering pinion case 11a, which is a part of the steering gear case 11, is fastened and fixed to the rear surface portion 19 of the suspension frame 3 by mounting brackets 17 and bolts 18 as shown in FIG. 3, and the steering pinion case 11a is installed at a low position. To this end, the lower portion S is disposed so as to project below the bottom surface portion 20 of the suspension frame 3.

On the other hand, on the bottom surface of the lower half 3b of the suspension frame 3, that is, on the bottom surface 20 of the suspension frame 3, a plurality of portions (for example, hatched lines α in FIG. (Two places shown)
A lower protruding portion 21 having an inclined surface 21a that protrudes downward and is inclined downward toward the rear of the vehicle body is provided by integral molding (bending molding). Is the suspension frame 3
The lowermost end 22 is formed.

Thus, the downwardly projecting portion 21 of the suspension frame 3 shown conceptually by oblique lines γ in FIGS.
Are disposed in front of a steering pinion case 11a, which is a part of the steering gear case 11, and a pair of attachment points M, N (see FIG. 2) of the steering pinion case 11a to the suspension frame 3, respectively. The lowermost end 22 of the lower protruding portion 21 is arranged to be lower than the lowermost ends of the steering pinion case 11a and the mounting points M and N.
As a result, the lower protruding portion 21 has a function as an underguard against a stepping stone or the like to the steering pinion case 11a and the mounting points M and N, and also functions as a skid plate for preventing the road surface from contacting them. It is configured to fulfill.

According to the vehicle body front structure having such a configuration, the lower portion 3b of the lower frame 3b of the suspension frame 3 supporting the steering gear case 11 and the lower control arm 16 protrudes downward. In addition, since the lower protruding portion 21 having the inclined surface 21a having a shape that is inclined downward toward the rear of the vehicle body is integrally formed to function as a skid plate, the presence of the lower protruding portion 21 enables steering even on a rough road. It is possible to reliably prevent a problem that the gear case 11 comes into contact with the road surface. In addition, since the lower protruding portion 21 is formed integrally with the suspension frame 3 by bending, the under guard conventionally provided separately can be omitted. Therefore, the number of parts and the number of assembling steps are reduced. And the cost can be reduced. Further, the lower protruding portion 21 is not provided in the entire region of the suspension frame 3 in the left-right direction of the vehicle body, but is arranged corresponding to only a necessary portion, that is, a pinion case 11a which is the lowermost end of the steering gear case 11 and a mounting portion thereof. Therefore, also in that respect, it is possible to reduce the weight, size and cost.

On the other hand, the provision of the above-mentioned downward protruding portion 21 on the suspension frame 3 makes it possible to arrange the steering gear case 11 and thus the steering gear at a low position, thereby providing an appropriate (small) toe angle. The change can be obtained, and the joint angle of the steering column can be reduced, so that a smooth steering feeling can be obtained.

Although one embodiment of the present invention has been described, the present invention is not limited to this embodiment, and various modifications and changes can be made based on the technical idea of the present invention. For example, the number of the lower protruding portions 21 provided on the bottom surface portion 20 of the suspension frame 3 is not limited to two, but may be three or more as necessary. Further, all of the lower protruding portions 21 may not be arranged on the vehicle body front side than the steering gear case 11, and a part thereof may be arranged on the vehicle body rear side with respect to the steering gear case 11.

[0017]

According to the first aspect of the present invention, an inclined surface is formed on a bottom surface of a suspension frame for supporting a suspension arm and a steering gear case, the inclined surface having a shape projecting downward and obliquely falling toward the rear of the vehicle body. According to the present invention, the lower protruding portion can be provided with a function as an underguard, and the underguard conventionally provided separately is provided according to the present invention. It can be omitted. Therefore, it is possible to reduce the number of parts and the number of assembling steps, and also to reduce the cost. In addition, the above-mentioned downward protruding portion can be easily formed integrally by bending the suspension frame, so that it is possible to construct a low cost, light weight and compact structure.

According to the second aspect of the present invention, the lowermost end of the downward projecting portion provided on the bottom surface of the suspension frame is disposed at a position lower than the lowermost end of the steering gear case. According to this, even when traveling on a rough road or the like, the lowermost end of the lower protruding portion of the suspension frame comes into contact with the road surface before the road surface tries to touch the ground with the steering gear case. Functions as a skid plate. Therefore, it is possible to reliably prevent the occurrence of a problem that the steering gear case is grounded.

According to a third aspect of the present invention, a plurality of the downward projecting portions are formed on the bottom surface of the suspension frame, and at least one of the plurality of downward projecting portions is formed by the steering gear case. Also, according to the present invention, the lower protruding portion can have a function as a skid plate as described above. The stepping stones can be prevented from hitting the steering gear case portion, and important portions such as a pinion case can be protected.

Further, according to the present invention as described above, it is possible to dispose the steering gear case and, consequently, the steering gear at a lower position on the vehicle body frame in accordance with the provision of the downward projecting portion on the suspension frame. Therefore, by adopting a configuration in which the steering gear case is arranged at a lower position on the body frame, it is possible to obtain an appropriate (small) change in toe angle, and also to reduce the joint angle of the steering column to obtain a smooth steering feeling. Can be.

[Brief description of the drawings]

FIG. 1 is a side view showing a vehicle body front structure of a four-wheeled vehicle according to an embodiment of the present invention.

FIG. 2 is a plan view of the vehicle body front structure described above.

FIG. 3 is a side view showing a state in which a steering gear case (pinion case) is attached to a suspension frame.

FIG. 4 is a front view as seen from the direction of arrow X in FIG.

5 (A) is a sectional view showing an upper half body and a lower half body which constitute the suspension frame, respectively, and FIG. 5 (B) is a view for explaining the structure of the suspension frame. () Is a side view showing a suspension frame formed by combining the upper half and the lower half with each other.

FIG. 6 is a side view for explaining a vehicle body front structure of a conventional four-wheeled vehicle, showing a state in which a steering gear case (pinion case) is attached to a suspension frame.

FIG. 7 is a side view for explaining a vehicle body front structure of another conventional four-wheeled vehicle and showing a state in which an underguard is provided below a steering gear case (pinion case).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Four-wheel vehicle 2 Cross member 3 Suspension frame 3a Upper half 3b Lower half 4 Steering mechanism 6 Front wheel 7 Steering shaft 10 Steering pinion 11 Steering gear case 11a Pinion case 12 Tie rod 13 Knuckle 16 Lower control arm 17 Mounting bracket 20 Bottom part 21 downward projection 21a inclined surface 22 bottom end

Claims (3)

[Claims] 1. A vehicle body front structure in which a suspension arm and a steering gear case are mounted on a suspension frame and at least a part of the steering gear case is disposed below the suspension frame. A vehicle body front structure provided with a downward protruding portion having an inclined surface projecting downward and obliquely falling toward the rear of the vehicle body. 2. The vehicle body front structure according to claim 1, wherein a lowermost end of the downward projecting portion is disposed at a position lower than a lowermost end of the steering gear case. 3. A plurality of the lower protruding portions are formed on a bottom surface of the suspension frame, and at least one of the plurality of lower protruding portions is disposed on the vehicle body front side with respect to the steering gear case. The vehicle body front structure according to claim 1 or 2, wherein: