JPH11245639A - Impact energy absorbing structure by torsion bar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a suspension mechanism part with an impact energy absorbing function in addition to a spring function primarily given by a torsion bar by devicing the disposition of the torsion bar emplyed by an independent type suspension mechanism part. SOLUTION: A stationary arm 2 is fixed to a cross member 7 at the front side of a vehicle frame 5, the tip end of a torsion bar 1 is fitted to the stationary arm 2, and the rear end of the torsion bar 1 is fitted to a lower arm 2 supported by a suspension cross member 10. By this constitution, the torsion bar 1 is roughly laid along a side frame 6 so as to be disposed in such a way as to be lightly inclined. External force applied to a vehicle is transmitted to the torsion bar 1 by way of the vehicle frame 5 to deform the torsion bar 1 thereby allowing it to maintain impact force and to absorb impact energy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention functions as a spring member of a suspension mechanism of an independent suspension type and absorbs impact energy due to external force at the time of a collision to reduce impact force applied to a vehicle and improve safety. To an impact energy absorbing structure using a torsion bar.

[0002]

2. Description of the Related Art Rigid suspensions using leaf springs and independent suspensions are often used as suspension systems. Among them, in the case of an independent suspension type suspension mechanism, a knuckle pin supported by an upper arm or a lower arm is provided at a portion of a high-rigidity suspension cross member which is bridged between left and right side frames of the frame. Concatenate. In addition, a coil spring, a torsion bar, or a shock absorber that engages with the lower arm or the like is generally used to elastically support the wheels. In the prior art, for example, even when the torsion bar is used, the torsion bar is mostly disposed rearward of the vehicle in consideration of the ground height and the like.

[0003]

When the torsion bar is arranged at the rear of the vehicle, the torsion bar does not function at least as a reinforcing member when an impact force is applied from the front of the vehicle. Therefore, the reinforcement of the vehicle at the time of the action of the impact force requires the provision of a reinforcing member around the frame and the cab.

The present invention has been made in view of the above circumstances, and a torsion bar used in an independent suspension type suspension mechanism also functions as an impact force holding member and an energy absorbing member when an external force is applied. At the same time, the purpose of the present invention is to provide a shock energy absorbing structure using a torsion bar that does not increase the cost or weight while reducing the deformation of the vehicle when an external force is applied without using any special parts, thereby improving the safety. And

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an independent suspension type suspension mechanism and a torsion bar which is arranged to absorb impact energy due to external force. An energy absorbing structure, wherein the torsion bar is disposed substantially along the side frame on the front side of the vehicle frame, the front end of which is fixed near the front end of the frame, and the rear end of which is connected to the lower arm. It constitutes an impact energy absorbing structure. The torsion bar is
It is characterized in that it is arranged to be slightly inclined outwardly from the front end toward the rear end side and slightly inclined downward.

The torsion bar of the present invention is provided at the front end of the frame of the vehicle in the longitudinal direction (front-back direction) of the left and right side frames.
, It functions as a torsion bar and also as a resistor against external force. Further, since it has an appropriate bending rigidity, it also functions as an impact energy absorbing member. Furthermore, since the torsion bar of the present invention is arranged to be inclined with respect to the direction in which the external force acts, the bending direction is stable and can function as an appropriate impact energy absorbing member.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of an impact energy absorbing structure using a torsion bar according to the present invention. As shown in FIGS. 1 and 2, the cab 4 is supported by a frame 5. The cab 4 shown is a cab-over type cab. The frame 5 is composed of side frames 6 and 6, which are juxtaposed at appropriate intervals, and cross members 7, 8, 9 and the like which are interposed therebetween. In particular, when the frame has an independent suspension type suspension mechanism, ,
The frame 5 has a high-rigidity suspension cross member 1
0 is suspended between the side frames 6 and 6. The cross member 7 among the cross members 7, 8, 9 is fixed to the front ends of the side frames 6, 6.

The base end of the upper arm 11 is pivotally supported by the side frame 6, and the base of the lower arm 3 (FIGS. 1 and 3) is pivotally supported by the suspension cross member 10. A knuckle 13 is connected to the free ends of the upper arm 11 and the lower arm 3 via a pole joint 12 or the like. The knuckle 13 has wheels 1
4 is supported. The upper arm 11 and the lower arm 3 are arranged so as to engage with a cushion portion such as a spring or a shock absorber (not shown). Also, as shown in FIGS. 1 and 2, an engine 15 is elastically mounted on the side frames 6, 6 or the suspension cross member 10 in the vicinity of the suspension cross member 10.

The torsion bar 1 of the present invention comprises a fixed arm 2
And an elongate rod member erected between the lower arm 3 and the lower arm 3. As shown in FIG.
Are arranged in such a manner as to extend in the left-right direction from the front end toward the rear end, and are disposed substantially along the longitudinal direction of the side frame 6 as shown. As shown in FIG. 2, the torsion bar 1 is disposed so as to be inclined downward from the front end toward the rear end. Note that, as shown in FIGS. 1 and 2, the inclination angle of the torsion bar 1 has a small value.

As shown in FIG. 3, the fixed arm 2 has a mounting hole 16 at one end and a fitting hole 1 at the other end.
7 comprising an arm-shaped member. The mounting hole 16 is fixed to the cross member 7 at the end of the frame 5 by a seat plate 18 and bolts 19. One end of the torsion bar 1 is fitted into the fitting hole 17.

As shown in FIG. 3, the lower arm 3 is composed of an elongated arm body 20, and the arm body 20 is pivotally connected to a fitting hole 21 at the rear end of the torsion bar 1 and the suspension cross member 10. Support hole 22 to be supported
Mounting seat 2 for fixing the stopper rubber 23
4 and the like, and a mounting portion 25 of the pole joint 12 is formed at the tip. Also, the knuckle 13
As described above, the lower arm 3 and the upper arm 11 are connected via the pole joint 12 and the unillustrated upper-side pole joint. Also, the shaft 26 of the nut 13
Is a support shaft for the wheels 14. As described above, the torsion bar 1 of the present embodiment has the fitting holes 17 of the fixed arm 2 and the lower arm 3.
And 21 are fitted along the front and rear directions of the vehicle with the front and rear ends fitted.

FIGS. 4 and 5 schematically show the arrangement of the torsion bar 1 of this embodiment. As shown in FIG. 4, the torsion bar 1 is arranged so as to open outward from the front end to the rear end, and is arranged so as to slope downward from the front end to the rear end as shown in FIG. .

The function of the torsion bar 1 arranged as described above as a spring member and a function as an impact energy absorbing member will now be described. First, the function as a spring member will be briefly described. Since the fixed arm 2 does not move, the front end of the torsion bar 1 is fixed. On the other hand, the rear end of the torsion bar 1 connected to the lower arm 3 moves on a predetermined arc as the wheels 14 move up and down. Therefore, the torsion bar 1 is subjected to torsion and bending. Since the torsion bar 1 is set to have a resistance to the torsion and bending, it functions as a spring member.

Next, the impact energy absorbing function of the torsion bar 1 will be described. As shown in FIGS. 1 and 2, when an external force F acts on the front surface of the cab 4 at the time of a collision or the like, a part of the external force F is applied to the frame 5. This force is distributed and applied to the side frames 6 and 6 of the frame 5 and the two torsion bars 1 and 1. As a result, as shown by the two-dot chain line in FIGS. 4 and 5, the torsion bars 1 and 1 are bent and deformed, and can retain the impact force and absorb the impact energy.

FIG. 6 shows an example of a load-displacement curve in which displacement is plotted on the horizontal axis and load is plotted on the vertical axis. The solid line is a curve (shown by A) when the torsion bar 1 according to the present invention is mounted, and the dotted line is a curve (shown by B) when the torsion bar 1 is not installed. In this diagram, A
The area enclosed by the curve and the B curve corresponds to the impact energy absorption. Therefore, it is clearly understood that the mounting of the torsion bar 1 by the amount indicated by the hatching in the figure has a larger impact energy absorption amount. Thus, the torsion bar 1
By devising the arrangement of the torsion bar 1, the torsion bar 1 can function as an impact energy absorbing member without impairing the original spring function. Needless to say, in the case of this example, no special separate member is required, so that problems such as cost increase and weight increase do not occur.

[0016]

According to the impact energy absorbing structure using the torsion bar according to the first aspect of the present invention, the torsion bar used for the independent suspension type suspension mechanism is arranged substantially along the side frame from the front end of the frame. By disposing them so as to function as a member that resists an external force applied to the vehicle, an impact energy absorbing function can be used in addition to the original spring function as a torsion bar. In the case of the present invention, a special additional member is not used unlike the prior art, so that cost increase and weight increase do not occur. 2) According to the impact energy absorbing structure using the torsion bar according to the second aspect of the present invention, the torsion bar is arranged at a relatively gentle inclination angle, the bending direction is stable, and the appropriate function of absorbing the impact energy is achieved. Can be.

[Brief description of the drawings]

FIG. 1 is a plan view showing an arrangement state of a torsion bar of the present invention.

FIG. 2 is a side view of FIG. 1;

FIG. 3 is a perspective view showing details of a connection structure of front and rear ends of the torsion bar of the present invention.

FIG. 4 is a schematic view for explaining an inclined state and an acting force of the torsion bar of the present invention.

FIG. 5 is a schematic diagram for explaining an inclined state and an acting force of the torsion bar of the present invention.

FIG. 6 is a load-displacement diagram for comparing the amount of impact energy absorbed when the torsion bar of the present invention is mounted and not mounted.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Torsion bar 2 Fixed arm 3 Lower arm 4 Cab 5 Frame 6 Side frame 7 Cross member 8 Cross member 9 Cross member 10 Suspension cross member 11 Upper arm 12 Pole joint 13 Knuckle 14 Wheels 15 Engines 16 Mounting hole 17 Fitting hole 18 Seat plate Reference Signs List 19 bolt 20 arm body 21 fitting hole 22 support hole 23 stopper rubber 24 mounting seat 25 mounting part 26 shaft (support shaft)

Claims (2)

[Claims] 1. An impact energy absorbing structure comprising a torsion bar, which is a component of an independent suspension type suspension mechanism and is arranged to absorb impact energy due to an external force, wherein the torsion bar is located on a front side of a vehicle frame. A shock-absorbing structure using a torsion bar, wherein the shock-absorbing structure is disposed substantially along the side frame, the front end of which is fixed near the front end of the frame, and the rear end of which is connected to the lower arm. 2. The impact energy absorbing structure using a torsion bar according to claim 1, wherein the torsion bar is arranged to be slightly inclined outwardly from a front end toward a rear side and slightly inclined downward. .