JP2004243831A - Front underrun protector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a front underrun protector reduced in weight and cost and having a bent material miniaturized and commonalized in the right and left sides. <P>SOLUTION: In the front underrun protector 1 attached with a hollow FUP main body 2 formed in a vehicle width direction in front of a car frame, the FUP main body 2 is divided into three portions of a left portion 2c, a center portion 2a and a right portion 2b in the vehicle width direction. The thickness of the center portion 2a is set to be thinner than those of the left portion 2c and the right portion 2b and three portions are connected. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a front underrun protector provided at the front of a vehicle in order to prevent one vehicle from entering under the other vehicle at the time of a collision between vehicles.
[0002]
[Prior art]
The front underrun protector is installed at the front of heavy vehicles such as trucks. When a collision with a medium or light weight vehicle such as a passenger car occurs (a rear-end collision, frontal collision, etc.) It prevents you from diving down and avoids major accidents. That is, the front underrun protector can be said to be a vehicle dive prevention device at the time of a collision (see Patent Document 1).
[0003]
As shown in FIG. 9, the front underrun protector 1 has a FUP main body 2 that extends in the vehicle width direction at the front of the vehicle. The FUP main body 2 is often formed into a closed cross-sectional shape, and has a bent portion 3 that is bent backward as viewed from above due to restrictions on vehicle layout. The FUP main body 2 is attached to a vehicle body frame (not shown) via a bracket 4 and a support 5, and supports a collision load to prevent the vehicle from getting into the vehicle.
[0004]
As shown in FIG. 9, the front underrun protector 1 under development by the present inventor has a bracket 4 welded to the back surface of the FUP body 2 and is L-shaped when viewed from above on the back surface of the bracket 4. The bent support 5 is fixed with bolts and nuts or the like, and the support 5 is attached to the vehicle body frame.
[0005]
[Patent Document 1]
JP 2001-515432 A [0006]
[Problems to be solved by the invention]
Incidentally, the front underrun protector 1 needs a predetermined rigidity in order to support a load at the time of collision.
[0007]
Therefore, as shown in FIG. 9, as one form of simulation at the time of a vehicle collision, a test in which a predetermined load (such as 50% of the vehicle weight) F1 is applied inside a predetermined length (such as 200 mm) from the outermost side of the vehicle, bracket 4 A test for applying a predetermined load (such as 100% of the vehicle weight) F2 to the position and a test for applying a predetermined load (such as 50% of the vehicle weight) F3 to the center are performed. The above load conditions are in accordance with European regulations.
[0008]
Here, in the FUP main body 2, the central portion 2 a between the left and right brackets 4, 4 can be structurally imitated as a both-end support beam, and both end portions 2 b, 2 c on the outer side in the vehicle width direction of each bracket 4, 4 are one piece. Can be imitated with a beam. For this reason, the center part 2a used as a cantilever beam needs less rigid strength than the both ends 2b and 2c used as a cantilever beam.
[0009]
However, the conventional FUP main body 2 is generally manufactured by bending a steel pipe or by welding parts that are divided in the middle in the vertical or front / rear direction. 2b and 2c are constant, and the plate thickness is set in accordance with the required rigidity strength of both end portions 2b and 2c. For this reason, the thickness of the central portion 2a is excessively thicker than necessary. This causes an increase in vehicle weight and cost.
[0010]
In addition, when the central portion 2a and the two end portions 2b and 2c are integrated in the vehicle width direction, the FUP main body 2 has a longer work length when bending the bent portion 3, so The handling is very bad. In addition, in order to form the left and right bent portions 3 and 3 for one FUP main body 2, it is necessary to perform two bending processes separately on the left and right sides.
[0011]
On the other hand, in the welded portion between the FUP body 2 and the bracket 4, the plate thickness changes in a step shape, so that the rigidity changes suddenly, and when the loads F1 to F3 are applied, the portion is broken, and the expected performance There is a problem of not exhibiting. Therefore, as shown in FIG. 10 and FIG. 11, a measure is considered in which the bracket 4 is provided with reinforcing plates 4x and 4y having a shape that alleviates a sudden change in rigidity when being superimposed on the FUP main body 2.
[0012]
However, since the brackets 4 with the reinforcing plates 4x and 4y are integrally formed in consideration of strength balance and assemblability, it is actually difficult to obtain an optimum and minimum shape in terms of strength and rigidity. For this reason, the weight also increases in the portion of the reinforcing plate 4.
[0013]
The object of the present invention, which was created in view of the above circumstances, is to provide a front underrun protector that achieves weight reduction and cost reduction, as well as miniaturization and common use of left and right bending materials. is there.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a front underrun protector in which a hollow FUP body molded in the vehicle width direction is attached to the front portion of a vehicle body frame, and the FUP body is disposed in the vehicle width direction. The left part, the central part, and the right part are divided into three parts, the thickness of the central part is set thinner than the left part and the right part, and they are connected.
[0015]
Moreover, you may provide the attachment bracket to a vehicle body frame in the said left side part and right side part. In addition, a reinforcing member that is formed so as to extend in the front-rear direction inside the left side portion and the right side portion may be accommodated so as to match the position of the mounting bracket.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to the accompanying drawings.
[0017]
As shown in FIG. 1, a front underrun protector 1 according to this embodiment has a hollow FUP body 2 molded in the vehicle width direction. In the illustrated example, the FUP main body 2 is formed into a rectangular cross section from an upper surface portion, a front surface portion, a lower surface portion, and a back surface portion, but may be formed into a circular cross section or an elliptical cross section.
[0018]
The FUP main body 2 is divided into a left side portion 2c, a central portion 2a, and a right side portion 2b in the vehicle width direction. The left side portion 2c and the right side portion 2b are formed with a bent portion 3 bent rearward as viewed from above due to restrictions on the vehicle layout. The left side portion 2c and the right side portion 2b are formed in a symmetrical shape, and can be used in common on the left and right sides by turning over.
[0019]
The central portion 2a is formed in a substantially straight shape. And as shown in FIG. 2, the plate | board thickness of the center part 2a is set thinner than the plate | board thickness of the left side part 2c and the right side part 2b. In the illustrated example, the central portion 2a is thinned so that the outer surface is flush with the outer surfaces of the left side portion 2c and the right side portion 2b, and the inner surface is stepped from the inner surfaces of the left side portion 2c and the right side portion 2b. And the center part 2a, the left side part 2c, and the right side part 2b are line-welded 6 along those abutting parts. However, as shown in FIG. 5, the central portion 2a may be thinner than the left side portion 2c and the right side portion 2b so that the inner surface is flush and the outer surface has a step.
[0020]
A mounting bracket 4 to the vehicle body frame is attached to the back surface of the left side portion 2c and the right side portion 2b by welding or the like. The mounting bracket 4 is formed by integrally forming flanges 4b at both ends of a substantially U-shaped cross-section material 4a, and the flanges 4b are fixed to the back surface of the left side 2c and the right side 2b by welding or the like. Then, as shown in FIG. 9, the support 5 is attached to the substantially U-shaped cross-section material 4a with bolts and nuts or the like. Further, the other end of the support 5 is attached to the vehicle body frame with bolts and nuts or the like.
[0021]
As shown in FIG. 3 and FIG. 4, a reinforcing member 7 that is stretched in the front-rear direction is accommodated in the left side portion 2 c and the right side portion 2 b so as to match the position of the mounting bracket 4. . In the illustrated example, the reinforcing member 7 is formed by bending both ends of a substantially rectangular plate material 90 degrees, and has a bent portion 7a at both ends and a central body portion 7b.
[0022]
The reinforcing member 7 is inserted into the inside from the openings 8 of the left side portion 2c and the right side portion 2b. Since this insertion portion has a substantially straight shape in the vehicle width direction, the insertion is easy. The reinforcing member 7 may be a box material instead of a plate material as long as the inside of the left side portion 2c and the right side portion 2b is extended in the front-rear direction.
[0023]
The reinforcing member 7 is matched with the position of the mounting bracket 4, its bent portions 7 a and 7 a are in contact with the front and rear inner surfaces of the left side portion 2 c (right side portion 2 b), and the main body portion 7 b is left side portion 2 c (right side portion). The interior of 2b) is spanned up and down substantially equally. The bent portion 7a is fixed to the inner surface by wire welding 11 (laser welding or the like).
[0024]
Thereafter, as shown in FIGS. 1 and 2, the center portion 2 a is welded to the left side portion 2 c and the right side portion 2 b to which the reinforcing member 7 is attached.
[0025]
The operation of the present embodiment having the above configuration will be described.
[0026]
As shown in FIG. 9, the above-described loads F1, F2, and F3 are applied to the front underrun protector 1 as one form of simulation at the time of a vehicle collision.
[0027]
At this time, the FUP main body 2 shown in FIG. 1 has the thickness of the center portion 2a imitated as a cantilever beam thinner than the thickness of the left side portion 2c and right side portion 2b imitated as a cantilever beam. As a result, the thickness can be reduced according to the required rigidity of each part, and weight reduction and cost reduction can be achieved without deteriorating the performance (rigidity) required as a whole.
[0028]
That is, the left side 2c and the right side 2b are cantilever beams that are thicker than the central portion 2a because the bracket 4 that is the support portion of the cantilever is attached to the inner part in the vehicle width direction. It exhibits rigidity as a cantilever corresponding to the thick plate thickness. On the other hand, since both ends of the center portion 2a are welded and fixed to the left side portion 2c and the right side portion 2b, rigidity as a doubly supported beam corresponding to the thin plate thickness is exhibited.
[0029]
In this way, the plate thickness of the central portion 2a (both ends of the beam), which requires a small required rigidity strength, is reduced, and the plate thickness of the left side portion 2c and the right side portion 2b (cantilever beam), which have a large required stiffness strength, is increased. The FUP main body 2 as a whole can achieve weight reduction and cost reduction while exhibiting a balanced rigidity as required.
[0030]
Further, the reinforcing member 7 not only improves the rigidity of the FUP main body 2 with respect to the loads F1, F2, and F3, but particularly improves the buckling resistance of the FUP main body 2 with respect to the load F2. That is, since the reinforcing member 7 is disposed at the position of the bracket 4, the load F <b> 2 can be received within the surface, and the received force is transmitted to the flange 4 b of the bracket 4. For this reason, the reinforcing member 7 becomes a tension member, and the hollow FUP main body 2 is not easily crushed.
[0031]
Moreover, since the left side part 2c and the right side part 2b are shape | molded in the left-right symmetric shape and can be used in common by right and left by turning upside down, it can manufacture with a common metal mold | die. Therefore, the cost is low. Further, when the bent portion 3 is formed by bending the left side portion 2c and the right side portion 2b, the length of the work (left side portion 2c, right side portion 2b) is shorter than the integrated type shown in FIG. The handling for the bending process is good and the bending process is easy.
[0032]
Another embodiment is shown in FIG.
[0033]
As shown in the figure, in this embodiment, the reinforcing member 7 is attached so as to partially protrude from the opening 8 of the left side 2c (right side 2b), and only the point that the protruding portion is covered with the central portion 2a is the previous embodiment. Is different. As shown in FIG. 2, the central portion 2a is set to be thinner than the thickness of the left side portion 2c and the right side portion 2b by matching the outer surface, and along the abutting portion between the left side portion 2c and the right side portion 2b. Wire welding 6 is performed. In this embodiment, at the time of wire welding, the central portion 2a is positioned to some extent by covering the protruding portion protruding from the opening portion 8 of the left side portion 2c (right side portion 2b). It becomes easy.
[0034]
Another embodiment is shown in FIG.
[0035]
As shown in the figure, in this embodiment, the central portion 2a of the embodiment shown in FIG. 6 is shaped as shown in FIG. That is, the central portion 2a is set to have a plate thickness that is adjusted to the inner surface as shown in FIG. Line welding is performed along the part. In this embodiment, at the time of wire welding, the central portion 2a is covered with the protruding portion protruding from the opening 8 of the left side portion 2c (right side portion 2b) without looseness, and is positioned more firmly than the embodiment of FIG. Therefore, welding work becomes easier. Further, the rigidity of the seam between the center portion 2a and the left side portion 2c (right side portion 2b) is improved.
[0036]
Another embodiment is shown in FIG.
[0037]
As shown in the drawing, in this embodiment, a plate-like reinforcing member 9 is accommodated in the bent portion 3 inside the left side portion 2c (right side portion 2b). The reinforcing member 9 has substantially the same configuration as the above-described reinforcing member 7 shown in FIG. 4, and is bent to a single radius. On the other hand, the bent portion 3 is also formed with a single radius. And the reinforcement member 9 is inserted along the radius from the opening part 10 of the edge part of the width direction of the left side part 2c (right side part 2b), and is welded 11 and fixed to the part which receives the load F1. The reinforcing member 9 becomes a tension member with respect to the load F1 in FIG. 9 and contributes to improvement in rigidity.
[0038]
【The invention's effect】
As described above, according to the front underrun protector according to the present invention, it is possible to reduce the weight and cost, and to reduce the size of the bending material and to make the right and left common.
[Brief description of the drawings]
FIG. 1 is a perspective view of a front underrun protector according to the present embodiment.
2 is a cross-sectional view taken along line II-II in FIG.
FIG. 3 is a partial plan view of FIG. 1;
4 is a cross-sectional view taken along the line IV-IV in FIG. 3;
FIG. 5 is a plan sectional view showing a modification of the central part of the FUP main body.
FIG. 6 is a plan view showing a modification of the reinforcing member.
FIG. 7 is a cross-sectional view showing a modification of a reinforcing member.
FIG. 8 is a plan view showing a modified example of the bent portion.
FIG. 9 is a perspective view of a front underrun protector under development by the inventors.
FIG. 10 is a perspective view of a bracket under development by the inventors.
FIG. 11 is a perspective view of a bracket under development by the inventors.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Front underrun protector 2 FUP main body 2a Center part 2b Right side part 2c Left side part 4 Mounting bracket 7 Reinforcement member

Claims (3)

A front underrun protector in which a hollow FUP main body molded in the vehicle width direction is attached to the front portion of the vehicle body frame, and the FUP main body is divided into a left side portion, a central portion, and a right side portion in the vehicle width direction. A front underrun protector, which is formed by dividing and setting the thickness of the central portion to be thinner than the left and right sides and connecting them. The front underrun protector according to claim 1, wherein a mounting bracket for a vehicle body frame is provided on the left side and the right side. The front underrun protector according to claim 2, wherein a reinforcing member molded in a front-rear direction is accommodated inside the left side portion and the right side portion so as to match the position of the mounting bracket.

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