JP3053000B2 - Safety device for cab-over type vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cab-over type vehicle that absorbs the impact of a collision to improve the safety of occupants.

[0002]

2. Description of the Related Art A conventional cab-over type vehicle is an actual vehicle.
As exemplified in Japanese Patent No. 29996, a guard member is arranged on the back surface of the front panel of the cab, and the guard member and the frame are connected by a hydraulic cylinder, so that the cab can be deformed by the guard member at the time of collision of the vehicle. The hydraulic cylinder absorbs the impact and protects the occupants by reducing the impact.However, since the guard member is arranged, the cab itself becomes large and the cab weight increases. There is a problem that the hydraulic cylinder connecting the shaft and the frame is inclined with respect to the front surface of the cab, so that the shock absorbing function of the hydraulic cylinder at the time of a vehicle collision does not always function smoothly.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cab-over type vehicle which has a simple structure and effectively absorbs the impact at the time of a vehicle collision to improve the safety of occupants.

[0004]

For this reason, a safety device for a cab-over type vehicle according to the present invention has a first and a second pair of left and right chassis frames extending substantially in the front-rear direction of the vehicle and extending in the vehicle width direction. A cross member, a second cross member having both ends connected to the pair of chassis frames and extending in the vehicle width direction and located above the first cross member, and a pair of left and right portions extending substantially in the front-rear direction of the vehicle below the cab And a third cross member extending in the vehicle width direction and connected to the first cross member, the second cross member, and the third cross member. Having a passed flexible member,
The third cross member, the first cross member, and the second cross member are set so that the breaking strength decreases in this order.

That is, a first cross member having both ends connected to a pair of left and right chassis frames and extending in the vehicle width direction, and a second cross member having both ends connected to the pair of chassis frames and extending in the vehicle width direction. A flexible member is hung on a third cross member having both ends connected to the pair of left and right cab reinforcing members and extending in the vehicle width direction, and a third cross member, a first cross member,
Since the breaking strength is set to be smaller in the order of the second cross members, the impact energy received by the cab due to the collision of the vehicle is first absorbed by the second cross member having the smallest breaking strength being deformed and destroyed. Next, the first cross member having the highest breaking strength is absorbed by deformation and destruction, and a large amount of energy is absorbed by these stepwise and continuous deformation and destruction. As a result, the impact on the cab is greatly reduced. Can be.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; 1 to 3, a cab-over type vehicle 1
A pair of main sills 3 extending substantially in the front-rear direction of the vehicle are provided on the lower left and right sides of the cab 2, respectively. Both ends of a cross pipe 4 extending in the vehicle width direction are fixed to the front ends of the main sills 3, respectively. The cab 2 is reinforced by 3 and a cross pipe 4, and an upper cab hinge bracket 5 is bolted to a tip of each main sill 3.

On the other hand, lower cab hinge brackets 7 are bolted to the ends of a pair of left and right chassis frames 6, respectively, and a torsion bar extending in the vehicle width direction through a through hole 8 of one of the lower cab hinge brackets 7 shown in the drawing. 9 is rotatably inserted, and the other end of the torsion bar 9 is inserted into the through hole of the other lower cab hinge bracket 7 (not shown) while the other end of the torsion bar 9 is prevented from rotating by serration engagement. Is configured.

In the lower cab hinge bracket 7 on one side shown in the drawing, a through hole 10 formed on the front side of the vehicle with respect to the cross pipe 4 and the through hole 8 is provided at one end of a torsion bar 11 extending in the vehicle width direction. Is prevented from rotating by serration engagement and is inserted therethrough, and the other end of the torsion bar 11 is rotatably inserted through a through hole of the other lower cab hinge bracket 7 (not shown) to form a second cross member. I have.

Further, upper cab hinge brackets 5 are rotatably mounted on both ends of the torsion bar 11 via rubber bushes 12, respectively, so that the cab 2 is rotatable about the torsion bar 11. Supported, the torsion bar 11 also constitutes a so-called cavitation shaft.

In this case, the breaking strength of the mounting portion of the lower cab hinge bracket 7 to which the torsion bar 11 is attached against the impact load acting on the cab 2 from the front of the vehicle is determined by the mounting portion of the lower cab hinge bracket 7 to which the torsion bar 9 is mounted. Of the lower cab hinge bracket 7 with respect to the chassis frame 6, and the torsion bar 9 of the lower cab hinge bracket 7.
The breaking strength of the mounting portion of the lower cab hinge bracket 7 or the breaking strength of the mounting bolt portion of the lower cab hinge bracket 7 is set smaller than the breaking strength of the fixing portion of the cross pipe 4 in the main sill 3.

Further, an annular flexible belt 13 having a large tensile strength is attached to the cross pipe 4 and the torsion bar 9.
, The side surface of the belt 13 abuts on the peripheral surface of the torsion bar 11 on the vehicle front side, and the belt 13 is connected to the cross pipe 4, the torsion bar 9, and the torsion bar 11
Has been substantially hung. In addition, 14 is an engine and 15 is an occupant.

Accordingly, when a collision occurs with the running vehicle 1 and a rearward impact is exerted on the front of the cab 2, in particular, above the chassis frame 6, the cab 2 firstly comes into contact with the upper cab hinge bracket 5 and the cab hinge shaft 11.
And a front cab hinge formed by a lower cab hinge bracket 7 and supported by a chassis frame 6 which is a main strength member of the vehicle 1.

However, if the impact is large, the cross pipe 4 and the torsion bar 9 are hung on the cross pipe 4 and the torsion bar 9 and the belt 13 whose side surface is in contact with the peripheral surface of the torsion bar 11 on the vehicle front side. Torsion bar 1 located on the front side of the vehicle with respect to bar 9
As a result, the torsion bar 11 is deformed, and the mounting portion of the lower cab hinge bracket 7 having a relatively small breaking strength is deformed and fractured. Even if the kinetic energy is absorbed and the mounting portion of the torsion bar 11 in the lower cab hinge bracket 7 is broken at this time, since the cross pipe 4 is connected to the torsion bar 9 by the belt 13, the cab 2
Is restrained from being largely displaced rearward of the vehicle.

Thereafter, the load on the cross pipe 4 also acts intensively on the torsion bar 9 by the belt 13, so that the torsion bar 9 is deformed and the torsion in the lower cab hinge bracket 7 having the next highest breaking strength. The mounting portion of the bar 9 or the mounting bolt portion of the lower cab hinge bracket 7 with respect to the chassis frame 6 is deformed and broken, whereby the kinetic energy of the impact is further absorbed.

As a result, as shown in FIG. 4, the relationship between the load F acting on the front surface of the cab 2 and the displacement x of the front surface of the cab 2 toward the rear of the vehicle is as follows: Is broken, and the first cross member breaks at point b, resulting in a broken line A. Compared with the broken line B in the case of the conventional vehicle, the amount of energy absorption corresponding to the hatched portion is smaller than that of the conventional vehicle. Is also increasing.

That is, the impact acting on the cab 2 at the time of the collision of the vehicle 1 is greatly absorbed as a result of the stepwise and continuous deformation and rupture of each part, so that the deformation of the cab 2 can be effectively suppressed, The impact on the occupant 15 can also be reduced, so that the occupant 15 can be protected from the collision of the vehicle 1 and the safety of the occupant 15 can be improved.

Further, in the above-described apparatus, the side of the belt 13 hung on the cross pipe 4 and the torsion bar 9 is provided on the vehicle front side of the torsion bar 11 disposed on the front side of the vehicle with respect to the cross pipe 4 and the torsion bar 9. Since it is in contact with the side peripheral surface, the impact acting on the cross pipe 4 and the torsion bar 9 when the vehicle 1 collides is
, The mounting portion of the lower cab hinge bracket 7 having a relatively small breaking strength is quickly deformed and ruptured, thereby effectively absorbing the collision energy. There are advantages that can be made.

Further, the structure of the belt 13 to be hung on the cross pipe 4 and the torsion bar 9 is extremely simple, inexpensive, lightweight, and can be easily applied to a conventional vehicle without major changes. The above-mentioned device is particularly excellent in practical effects.

Even if the belt 13 is hung on the cross pipe 4 and the torsion bar 9, the torsion bar 1
The tilt operation for rotating the cab 2 around the center 1 does not cause any trouble, and the handling thereof is no different from the conventional one.

Although the belt 13 is hung on the cross pipe 4 and the lower torsion bar 9 in the above embodiment, as shown in FIG. The belt 13 is wrapped around the cross pipe 4 and the torsion bars 9 and 11 by wrapping the belt 13 around the cross pipe 4 and the torsion bars 9 and 11 with the fastener 20 and winding the belt 13 around the cross pipe 4 and the upper and lower torsion bars 11 and 9. It goes without saying that the same operation and effect as those of the above-described embodiment can be achieved even if passed.

[0021]

In the safety device for a cab-over type vehicle according to the present invention, the first cross member, the second cross member, and the third cross member are each provided with a flexible member.
The breaking strength is set to decrease in the order of the third cross member, the first cross member, and the second cross member, and the impact energy received by the cab due to the collision of the vehicle is gradually and stepwise from the cross member having the lowest breaking strength. As a result of being absorbed by continuous deformation and destruction, a large amount of kinetic energy is reliably absorbed, and the impact received by the cab can be significantly reduced. Safety can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic side view of an embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of the embodiment.

FIG. 3 is a vertical sectional view taken along the line III-III in FIG. 2;

FIG. 4 is a diagram illustrating the operation of the embodiment.

FIG. 5 is a side view of a main part according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vehicle 2 Cab 3 Main sill 4 Cross pipe 5 Upper cab hinge bracket 6 Chassis frame 7 Lower cab hinge bracket 9, 11 Torsion bar 13 Belt 14 Engine 15 Passenger

Continued on the front page (56) References JP-A-10-45042 (JP, A) JP-A-3-40176 (JP, U) JP-A-6-42544 (JP, U) JP-A-6-59193 (JP) , U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B62D 33/06 B62D 25/20

Claims (4)

(57) [Claims] 1. A first cross member having both ends connected to a pair of left and right chassis frames extending substantially in the front-rear direction of a vehicle and extending in the vehicle width direction, and both ends connected to the pair of chassis frames, respectively, in the vehicle width direction. A second cross member extending above the first cross member and a pair of left and right reinforcing members extending substantially in the front-rear direction of the vehicle below the cab, both ends of which are connected to each other and extending in the vehicle width direction. A third cross member positioned above the member, and a flexible member hung on the first cross member, the second cross member, and the third cross member;
A safety device for a cab-over type vehicle, wherein the first cross member and the second cross member are set so that the breaking strength decreases in this order. 2. The cab-over type vehicle safety device according to claim 1, wherein the first cross member and the third cross member are arranged on the vehicle rear side of the second cross member. 3. The cab-over type vehicle safety device according to claim 1, wherein the second cross member is a cab tilt shaft and a mounting bracket thereof. 4. The second cross member according to claim 1, wherein the first cross member comprises a torsion bar for cab tilt, a mounting bracket thereof, and a connecting portion of the mounting bracket to the chassis frame. Is a safety device for a cab-over type vehicle, which is a torsion bar for cab tilt and its mounting bracket.