JPH09267633A - Impact bar for vehicle door - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle door impact bar whose cross-sectional structure can prevent a vehicle door thickness and weight horn increasing and has high resistance against bending in an elastic deformation area and high resistance against breaking also in a plastic deformation area. SOLUTION: This impact bar is disposed inside a door which forms a vehicle side surface and constituted so as to restrain deformation of the door at the time of load input caused by collision from the side of the vehicle. A roughly cylindrical cross-section structure is constituted so that a plate 1 whose both edge parts are in an irregular teeth form is rolled and an overlapped connection part 4 fitted each other into the inner periphery side of recessed parts 3 which protruding parts 2 at both the edge parts faces each other is provided in the vicinity of a neutral axis A for load P inputting direction. The outer surface 2a of the protruding part 2 and the edge 3a of a recessed part 3 are formed so as to maintain a fixed clearance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is arranged inside a door forming a side surface of a vehicle in order to increase the strength of the door against a load input from the side surface of the vehicle when another vehicle collides from the lateral direction. The present invention relates to an improvement of an impact bar of a vehicle door that improves vehicle driver safety by suppressing deformation of the door.

[0002]

2. Description of the Related Art As a conventional impact bar of this type, for example, one shown in FIG. 8A (hereinafter referred to as type A) is known. That is, in the type A impact bar, the plate material 101 is rolled and both ends thereof are joined by the joining portions 102 to form a pipe shape.
2 in the input direction of the load P (shown by the arrow) and welded part Y
It has been subjected to.

However, since the type A has a cylindrical shape, the bending resistance value in the elastic deformation region (from the moment the load is input to the initial stage, the same hereinafter) is somewhat high, but the welded portion Y, which is weak against impact load, is applied. Since the joint portion 102 is arranged in the input direction of the load P, that is, in a portion where the maximum compressive stress is generated when the load P is input, when a considerable impact occurs in a collision with another vehicle or the like, the plastic deformation region is generated. There is a defect that the fracture resistance value is low at the stage (after the load input, when the elastic limit is exceeded, the same applies hereinafter), and buckling deformation is likely to occur.

Further, in the manufacturing process of the type A impact bar, welding work is indispensable work. However, in the welding work, a large amount of fumes causing occupational diseases such as pneumoconiosis occur and the factory environment deteriorates. Not only is there
Light from the operator's eyes due to the arc (hereinafter referred to as arc light)
In addition to the need for shielding equipment against arc light in order to protect it from the above, there is a problem that the welding operation itself requires an extremely complicated operation such as spatter removal and distortion removal.

As another type of conventional impact bar of this type, for example, one shown in FIG. 8B (hereinafter referred to as type B) is known. That is,
The impact bar of type B is one in which the plate member 103 is rolled and both ends thereof are joined by the joining portions 104 to form a pipe shape, and the joining portions 104 are arranged on the side opposite to the input direction of the load P (arrow shown in the figure). Therefore, unlike the type A, the joint 104 is not welded.

However, in the type B impact bar, in order to obtain the same strength as that of the type A, the plate material 1
It is necessary to make the thickness dimension of 03 larger than the thickness dimension of the plate material 101 of type A, the outer diameter dimension W2 of the plate material 103 to be larger than the outer diameter dimension W1 of type A, or both of them. Therefore, there is a problem that the door becomes thick and the door becomes heavy.

[0007]

SUMMARY OF THE INVENTION Therefore, the present invention has been made in view of the above-mentioned problems, and the elasticity of the vehicle door is improved while avoiding the situation where the thickness and weight of the vehicle door become large. It is an object of the present invention to provide an impact bar for a vehicle door having a cross-sectional structure having a high bending resistance value in the deformation region and a high fracture resistance value after transition to the plastic deformation region.

[0008]

That is, an impact bar of a vehicle door according to the present invention is arranged inside a door constituting a side surface of a vehicle, and is deformed when a load is input due to a collision from the vehicle side surface. In the impact bar of a vehicle door that suppresses the above, a plate member 1 having both end portions having an uneven tooth shape is rounded, and in the vicinity of the neutral axis A with respect to the load P input direction, a convex portion 2 at both end portions of a concave portion 3 facing each other. It is characterized in that it has a cross-sectional structure having a substantially cylindrical shape in which the overlapping connection portions 4 which are fitted into each other on the inner peripheral side are provided and are integrally connected.

In such a technical means, the outer surface 2a of the convex portion 2 and the end side 3a of the concave portion 3 may have a constant gap.

The impact bar of another vehicle door according to the present invention is disposed inside the door constituting the side surface of the vehicle, and suppresses deformation of the door when a load is input due to a collision from the side surface of the vehicle. In the impact bar of the door for
Both ends of the plate member 11 having both end portions having an irregular tooth shape are rounded except for the central portion 12, two mountain-shaped apex portions 13 are provided on the sides facing in the load P input direction, and in the vicinity of the center line B. It is characterized in that the convex portions 14 at both ends are fitted into the concave portions 15 facing each other so as to intersect with each other, and the central portion 12 of the plate member 11 has a cross-sectional structure in which an end side 14a of the convex portion 14 obliquely abuts. It is a thing.

In such a technical means, the outer surface 14b of the convex portion 14 and the end side 15a of the concave portion 15 may have a constant gap.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings. First Embodiment FIG. 3 shows the first embodiment when the impact bar of the vehicle door according to the present invention is applied to the left rear door of an automobile.

In the figure, the impact bar unit 2
1 is an impact bar 22 having a substantially cylindrical cross section
And a front bracket 2 arranged at the front of the left rear door
3 and a rear bracket 2 arranged at the rear of the left rear door
4, the impact bar 22 is attached to the front bracket 23 and the rear bracket 24 by welding with the both ends as welded portions Y by arc welding to be integrated.

The impact bar unit 21 having the above-described structure includes the front bracket 23 and the rear bracket 2.
4 is attached by spot welding to an inner panel (not shown) of the left rear door at an appropriate position around the periphery of the No. 4.

Further, in this embodiment, as shown in FIGS. 3 (b) and 3 (c), the impact bar 22 has a superposed connecting portion near the neutral axis A with respect to the direction of the center line B to which the load is input. 25 has a substantially cylindrical cross-sectional structure.

That is, in the impact bar 22 according to the first embodiment, as shown in FIG. 4 (a), a plate member 31 having both end portions having a concave and convex tooth shape and having a thickness t is rounded, In the vicinity of the neutral axis A with respect to the input direction of the load P, there is provided a superposed connecting portion 25 which is fitted into the inner peripheral side of the concave portion 33 where the convex portions 32 at both ends face each other, and is integrally connected to have an outer diameter dimension. It has a substantially cylindrical cross-sectional structure of W,
A constant gap 34 is provided between the outer side surface 32 a of the convex portion 32 and the end side 33 a of the concave portion 33.

Further, when manufacturing the impact bar 22 according to the first embodiment, both ends of the plate material 31 are recessed portions 33.
Since the convex and convex portions 32 and the convex portion 32 are fitted into each other in a concavo-convex tooth shape, the shear lines 35 at both ends of the plate material 31 can be commonly used as the shear lines of the adjacent plate materials 36 and 37.
As described later, since the concave portion 33 and the convex portion 32 function as the shock absorbing member, it is possible to effectively use the material.

That is, the plate member 31 of the impact bar 22
As shown in FIG. 4B, the material of a predetermined plate material is removed so as to form a concave-convex tooth profile with reference to the protruding length dimension L1 of the convex portion 32 (see FIG. 4A). By doing so, since the concavo-convex tooth-shaped shapes of the adjacent plate materials are formed at the same time, it is possible to eliminate the occurrence of waste during material removal, and it is also possible to reduce the manufacturing labor.

As the material of the plate member 31 in this embodiment, a cold rolled steel plate having a tensile strength of 980 N / mm 2 is used.

In FIG. 4B, the length dimension L2 is a length dimension determined by design from the outer diameter dimension W of the impact bar 22 shown in FIG. The length L3 is the full extension of the impact bar 22.

Next, the operation of the vehicle equipped with the impact bar 22 constructed as described above when another vehicle collides laterally will be described with reference to FIG. In this case, the impact bar 22 will change over time from the time of input of the load P as shown in FIGS. 5A to 5D, as described below.

(A) Elastic deformation region At the moment when another vehicle collides from the lateral direction, when the body member 41 of the door is crushed due to the collision, the impact bar 2 is almost at the same time.
The load P is input to the impact bar 22 from the direction along the center line B of the impact bar 22.

Then, the impact bar 22 has the plate member 31.
Due to the elasticity of the cold-rolled steel sheet, which is the material of, and the high bending resistance of the substantially cylindrical cross section, it will be slightly elastically deformed, and the cross section of the substantially cylindrical shape is slightly crushed and looks like a horizontally long ellipse. It takes on a shape.

At this time, since the cross section of the impact bar 22 is substantially cylindrical, the load P is equal to the load of the impact bar 22.
Is input in the direction of the center line B from a point on the outer periphery of the center line B. Therefore, in the cross section of the impact bar 22, both the maximum compressive stress generating position 42 and the maximum tensile stress generating position 43 are arranged such that the circumferential length from the overlap connection portion 25 is the longest, in other words, Since the overlapping connection portions 25 are arranged in the positional relationship in which the bending resistance value is the highest, elliptical deformation is difficult to occur, which means that it is difficult to shift from the elastic deformation region to the plastic deformation region.

(B) Elastic Deformation Region-Plastic Deformation Region When the load P is further input and the elastic deformation progresses, the cross-sectional force of the impact bar 22 that tries to resist its own bending increases. In this case, the magnitude of the cross-sectional force exceeds the magnitude of the connecting force due to the concave portion 33 and the convex portion 32 of the overlapping connection portion 25 being fitted to each other.

As a result, the concave portion 33 and the convex portion 32 are pushed into each other at the portion where the concave portion 33 and the convex portion 32 of the overlapping connection portion 25 are fitted to each other, and as a result, the outer surface 32a of the convex portion 32 is The gap 34 existing between the recess 33 and the end side 33a disappears, and after the gap 34 disappears, the elastic deformation region shifts to the plastic deformation region.

At this time, the bite between the concave portion 33 and the convex portion 32 plays a role of buffering the impact due to the collision, and a part of the impact is absorbed. This means that the impact bar 22 has a sectional structure. This means that it has a high impact resistance and a high fracture resistance.

(C) Plastic deformation region (first step) Next, when the elastic deformation region ends and a further load P is input, at this time point, the maximum compressive stress and the maximum tensile stress are exceeded, and therefore the plastic deformation region is exceeded. However, in this case, the elliptical shape of the cross section of the impact bar 22 is no longer maintained, and the impact bar 22 simply shifts to the crushing plastic deformation region.

(D) Plastic deformation region (second stage) When the load P is further input, plastic deformation progresses and the cross section of the impact bar 22 is crushed. Has a structure in which the plate members 31 are overlapped with each other, which makes it difficult to plastically deform. Further, since the recesses 33 and the protrusions 32 are fitted to each other, destruction progresses and the overlapping connection portion 25 is closed. Since it does not open, it is prevented that the cross-sectional shape of the impact bar 22 is significantly collapsed as the plastic deformation progresses, and the above process is secured.

Second Embodiment FIG. 6 shows a second embodiment when the impact bar of another vehicle door according to the present invention is applied to the left rear door of an automobile.

In the figure, the impact bar unit 5
Reference numeral 1 denotes an impact bar main body 52 having a cross section with two mountain-shaped apexes, an impact bar attachment front 53 disposed in the front of the left rear door, and an impact bar attachment front 53 disposed in the rear of the left rear door. The impact bar main body 52, the impact bar front part 53, and the impact bar rear part 54 are made of the same plate material and are continuously formed.

The impact bar unit 51 thus constructed is spot-welded to the inner panel (not shown) of the left rear door at appropriate places around the impact bar attachment front portion 53 and the impact bar attachment rear portion 54. It is attached. The impact bar unit 51 according to the second embodiment does not require welding work because the mounting portion for the inner panel (not shown) and the impact bar are not separately configured. It can be said that it is superior to 1.

Further, as shown in FIG. 7A, the impact bar main body 52 according to the second embodiment is rounded on both sides except for the central portion 62 of a plate member 61 having both end portions having an uneven tooth shape. Then, two mountain-shaped apexes 63 are provided on the sides facing each other in the input direction of the load P, and in the vicinity of the center line B, the convex portions 64 at both ends intersect at the intersecting portions 65 and are fitted into the opposing concave portions 66. In addition, the central portion 62 of the plate member 61 has a cross-sectional structure in which the end side 64a of the convex portion 64 obliquely abuts, and a constant distance is provided between the outer surface 64a of the convex portion 64 and the end side 66a of the concave portion 66. It has a gap 67.

Next, the operation when another vehicle laterally collides with the vehicle equipped with the impact bar main body 52 constructed as described above will be described with reference to FIG. In this case, the impact bar main body 52 changes with time from the time of inputting the load P as shown in FIGS. 7A to 7D, as described below.

(A) Elastic deformation region At the moment when another vehicle collides from the lateral direction, when the body member 71 of the door is crushed due to the collision, the vehicle comes into contact with the impact bar main body portion 52 at substantially the same time, and the center line of the impact bar main body portion 52. The load P is applied to the impact bar main body 52 from the direction along B.
Is entered.

Then, the impact bar main body 52 is slightly elastically deformed due to the elasticity of the cold-rolled steel plate as the material of the plate member 61 and the characteristics of the cross section having the mountain-shaped apex portions 63 arranged in parallel. The cross section having the two mountain-shaped apexes 63 is slightly collapsed as a whole.

At this time, since the impact bar main body 52 has a cross section in which the two mountain-shaped apexes 63 are arranged in parallel, the load P is determined by the center line B from the two mountain-shaped apexes with which the body member 71 abuts. Entered in the direction. For this reason, since the load P is received by both of the two mountain-shaped apexes 63, it becomes difficult for bending deformation to occur, which means that the cross-sectional structure of the impact bar main body 52 shifts from the elastic deformation region to the plastic deformation region. It means that it is difficult.

(B) Elastic Deformation Region-Plastic Deformation Region When the load P is further input and the elastic deformation progresses, the impact bar main body portion 5 tries to resist its own bending.
However, in this case, the magnitude of this cross-sectional force exceeds the magnitude of the connecting force due to the projections 64 fitting together at the intersection 65.

Then, in the fitting portion of the convex portion 64 of the intersecting portion 65, the concave portion 66 and the convex portion 64 are hard to fit into each other, and as a result, the outer side surface 64a of the convex portion 64 and the concave portion 66.
The gap 67 existing between the edge side 66a and the end side 66a disappears, and after the gap 67 disappears, the elastic deformation region shifts to the plastic deformation region.

At this time, the bite between the concave portion 66 and the convex portion 64 plays a role of buffering the impact due to the collision, and a part of the impact is absorbed. This means that the impact bar main body 52 has a cross section. This means that the structure has a high impact resistance and a high fracture resistance.

(C) Plastic deformation region (first stage) Next, when the elastic deformation region ends and a further load P is input, the elastic limit is exceeded at this point, so the region is shifted to the plastic deformation region. However, in this case, first, since the plastic deformation starts from the convex portion 64 in which the end side 64a is in contact with the central portion 62 of the plate material 61, the shape of the outer peripheral portion of the cross section may be suddenly collapsed. This means that the sectional structure of the impact bar main body 52 has a high fracture resistance value.

(D) Plastic Deformation Region (Second Stage) When the load P is further input after the plastic deformation of the convex portion 64 is completed, the plastic deformation progresses and the cross section of the impact bar main body portion 52 is changed. Although it will be crushed, even at this stage, the impact bar body 5 with a high fracture resistance value
Since most of the cross-sectional structure of the outer peripheral part of 2 exists,
Not only is it difficult to be plastically deformed, but there is also an internal intersection 65 of the convex portion 64.
In addition, since the plate members 31 are overlapped with each other and the plate members 31 are overlapped with each other, it is more difficult for the plastic members to be deformed. Further, since the concave portions 66 and the convex portions 64 are fitted to each other, the fracture progresses and the intersection portion 65 is formed. Since the mouth is not opened, it is possible to prevent the situation in which the cross-sectional shape of the impact bar 22 is significantly collapsed as the plastic deformation progresses, so that the above process is secured.

In the second embodiment as well, as in the first embodiment, since the concave and convex shapes are such that the concave portions and the convex portions fit into each other, the shear lines at both ends of the plate material are adjacent to each other. In addition to being able to be used in common with the shear line of the plate material, since the concave and convex portions are shock absorbing members, the material can be used more effectively.

[0044]

As described above, according to the present invention, a plate member having both end portions having concave and convex tooth shapes is rounded, and a concave portion where the convex portions at both ends face each other near the neutral axis with respect to the load input direction. Since the cross-sectional structure is a substantially cylindrical shape that is integrally connected and provided with a superposed connection portion that is inserted into each other on the inner peripheral side, it is possible to increase the bending resistance value in the elastic deformation region and to increase the plastic deformation region. It is possible to increase the breaking resistance value after the transition, and it is also possible to effectively avoid the situation where the thickness and weight of the vehicle door become large. As a result, the safety of the vehicle driver, the vehicle The door will be lighter in weight.

Further, according to another embodiment of the present invention, both sides except the central portion of the plate material having both end portions having the concave and convex tooth shape are rounded, and two mountain-shaped vertices are provided on the side facing in the load input direction. Since a section is provided in the vicinity of the center line, the projections at both ends are inserted into the opposing recesses so as to intersect with each other, and the central portion of the plate member has a cross-sectional structure in which the end sides of the projections obliquely contact each other. , It is possible to increase the bending resistance value in the elastic deformation region, it is also possible to increase the fracture resistance value after transition to the plastic deformation region, moreover, the thickness dimension of the vehicle door,
Since it is possible to effectively avoid the situation where the weight becomes large, as a result, the safety of the vehicle driver and the weight reduction of the vehicle door are achieved.

Further, in both of these inventions, since both end portions of the plate material have a concavo-convex tooth shape in which the concave portions and the convex portions are fitted to each other, the shear lines of the both end portions of the plate material are the shear line of the adjacent plate material. In addition to being commonly used, the concave and convex portions are shock absorbing members, so that the material can be used more effectively.

Furthermore, in these inventions, in particular, if the outer surface of the convex portion and the edge of the concave portion maintain a constant gap, the bending resistance value in the elastic deformation region can be increased, and The effect that the fracture resistance value after the transition to the plastic deformation region can be increased can be made more remarkable.

[Brief description of drawings]

FIG. 1 is a schematic view showing a basic structure of an impact bar of a vehicle door according to the present invention.

FIG. 2 is a schematic diagram showing a basic structure of an impact bar of another vehicle door according to the present invention.

FIG. 3 is an explanatory diagram showing an impact bar unit according to the first embodiment to which the present invention is applied.

FIG. 4 is an explanatory diagram of a basic cross section and material removal showing an impact bar according to the first embodiment to which the present invention is applied.

FIG. 5 is an operation explanatory diagram when a load is input to the impact bar according to the first embodiment to which the present invention is applied.

FIG. 6 is an explanatory diagram showing an impact bar unit according to a second embodiment of the present invention.

FIG. 7 is an operation explanatory diagram when a load is input to the impact bar main body according to the second embodiment to which the present invention is applied.

FIG. 8 is a cross-sectional structure diagram of a conventional impact bar.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Plate material 2 ... Convex part 3 ... Recessed part 4 ... Overlapping connection part 11 ... Plate material 12 ... Central part 13 ... Apex part 14 ... Convex part 15 ... Recessed part 21 ... Impact bar unit 22 ... Impact bar 23 ... Front bracket 24 ... Rear part Bracket 25 ... Overlapping connection portion 31 ... Plate material 32 ... Convex portion 33 ... Recessed portion 34 ... Gap 35 ... Shear line 36 ... Adjacent plate material 41 ... Body member 42 ... Maximum compressive stress generation position 43 ... Maximum tensile stress generation position 51 ... Impact bar Unit 52 ... Impact bar main body portion 53 ... Impact bar attachment front portion 54 ... Impact bar attachment rear portion 61 ... Plate material 62 ... Central portion 63 ... Apex portion 64 ... Convex portion 65 ... Intersection portion 66 ... Recessed portion 67 ... Gap 101 ... Plate material 102 ... Joining part 103 ... Plate material 104 ... Joining part A ... Neutral axis B ... Center line P ... Load O ... Car exterior side I ... Car interior side Y ... Weld part ... outer diameter t ... thickness dimension

Claims (4)

[Claims] 1. An impact bar of a vehicle door, which is disposed inside a door forming a side surface of a vehicle and suppresses deformation of the door when a load is input from a collision from the side surface of the vehicle. The plate material (1) to be rolled is rolled,
Near the neutral axis (A) with respect to the load (P) input direction, there is provided an overlapping connection part (4) which is fitted into the inner peripheral side of the concave part (3) where the convex parts (2) at both ends face each other. An impact bar for a vehicle door, which has a substantially cylindrical cross-sectional structure connected to the. 2. The vehicle according to claim 1, wherein a constant gap is maintained between the outer side surface (2a) of the convex portion (2) and the end side (3a) of the concave portion (3). Door impact bar. 3. An impact bar of a vehicle door, which is disposed inside a door forming a side surface of a vehicle and which suppresses deformation of the door when a load is input due to a collision from the side surface of the vehicle. The central part (1
Both sides except 2) are rounded, and two chevron-shaped apexes (13) are provided on the side facing the load (P) input direction,
In the vicinity of the center line (B), the convex portions (14) at both ends are fitted into the concave portions (15) facing each other so as to intersect, and the plate material (1
In the central part (12) of (1), the end sides (14
The impact bar of a vehicle door is characterized in that a) has a cross-sectional structure that abuts diagonally. 4. The vehicle according to claim 3, wherein a constant gap is maintained between the outer side surface (14b) of the convex portion (14) and the end side (15a) of the concave portion (15). Door impact bar.