JP2000081069A - Impact absorbing member for vehicle and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To apply a single die set to many specifications without causing any bending in extension of the full length by constituting an impact absorbing member into a hollow and approximately truncated cone shape with the diameter set continuously large from the front edge to the rear edge by a plate member. SOLUTION: A member 10 is so formed that semi-truncated cone members 11, 12 of semicircular cross section, which is continuously set large from the front edge (a) to the rear edge (b) by a plate member, are mated with its inside being hollow and the mated faces 13 are welded to each other. Though a tapered angle α is decided by an experiment lastly, it is basically reduced without bent by a prescribed impact compression load while applying an appropriate resistance to the whole length. The manufacturing method is that a pair of dies having the minimum and the maximum values of the dimension of the semicircular section from the front edge to the rear edge of the member and the maximum value of the full length in the axial direction are prepared and a necessary-dimension and board thickness material is formed at an appropriate position of the die. This single pair of dies can cause no bending by the impact compression load in extension of the full length, can be reduced, and applied to many specifications.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle impact absorbing member and a method of manufacturing the same.

[0002]

2. Description of the Related Art A conventional shock absorbing member for a vehicle has a shape as shown in FIGS. 9 and 10, that is, a combination of U-shaped members 2, 3 having a bead 1 formed on a side wall. In addition, one having a uniform rectangular cross-section in which the cross-sectional area only changes at regular intervals in the longitudinal direction (FIG. 9), or a circular cross-section in which the reduced diameter portion 5 having the same diameter is formed at predetermined intervals of the circular tube 4 is used. It is known to have a circular cross-section (not shown) with a helical diameter, which is connected at one end by a suitable connecting member or directly to a vehicle, for example a truck. Frame (not shown) was used by being fixed to the front end.

In this case, the shock absorbing member as described above absorbs a shock by receiving a compressive load in the axial direction and contracting while resisting the shock, thereby reducing the damage to the frame, the body and the like. Is the impact compressive load P received by the shock absorbing member and the shrinkage (shrinkage) of the shock absorbing member.
The relationship of the quantity L is desirably as shown by the solid line in FIG.
That is, according to the characteristics of the vehicle to which the shock absorbing member is attached, it is preferable that the hatched area be rectangular so that the load P is kept within a certain limit and the energy absorption indicated by the hatched area is as large as possible. It has been.

However, in the conventional shock absorbing member as shown in FIGS. 9 and 10, if the total length of the member is increased in order to increase the amount of energy absorption, the shock absorbing member becomes longer than a certain length. It may be bent (falled) before being crushed and contracted, and consequently the energy absorption may be significantly reduced as shown by the broken line in FIG. Further, in the conventional shock absorbing member as described above, when the cross-sectional dimensions, plate thickness, material, and overall length are determined according to the type of vehicle to be mounted and various required specifications for the shock absorbing member, correspondingly. Individual molds were required, which contributed to the cost increase.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a vehicle for a vehicle that does not bend (fall) before contraction (reduction) due to a compressive load even when the overall length of the shock absorbing member is increased. An object of the present invention is to provide a shock absorbing member and a method of manufacturing a vehicle shock absorbing member capable of responding to many specifications with one set of molds.

[0006]

According to the present invention, there is provided a shock absorbing member for a vehicle, wherein the diameter is continuously increased from a front end to a rear end by a plate member to form a hollow substantially frusto-conical shape. The first invention, characterized in that it is formed into two half-sectioned members having a semicircular cross-section and having a continuously increasing cross-sectional area from the front end to the rear end by a plate member, the inside of which is hollow. The second invention, characterized in that they are formed by welding and the mating surfaces are welded, and a plate member,
A third feature in which two half-section members having a semicircular cross section whose radius is gradually increased from the front end to the rear end are formed so as to form a hollow inside, and the mating surfaces are welded. The method for manufacturing a vehicle shock absorbing member according to the present invention comprises a semi-circular cross section from the front end to the rear end of the shock absorbing member necessary for all vehicles to which the vehicle shock absorbing member is applied. A mold having the minimum value and maximum value of the height and the maximum value of the total length in the axial direction is prepared, and a material having the size and plate thickness required for the target vehicle is formed by the appropriate position of the mold. It is characterized by doing.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to FIGS.
As shown in FIGS. 1 to 5, the diameter is continuously increased from the front end to the rear end, and FIGS.
As shown in FIG. 2, the diameter is gradually increased from the front end to the rear end. The shock absorbing member 10 shown in FIG. 1 has two half-cut members 11 and 12 having a semi-circular cross-section, whose cross-sectional areas are continuously increased from a front end a to a rear end b, by a plate member. They are formed so as to be formed, and the mating surfaces 13 are welded.

In this case (although it is not limited to the one shown in FIG. 1), the taper angle α is finally determined by an experiment. It is important to reduce while giving resistance. Further, in the example of FIG. 1, the pipes are formed by welding half-sectioned pieces in the radial direction to face each other, but if there is a circular pipe having an appropriate material and diameter, the pipe is expanded in a tapered shape from one end to the other end. Alternatively, it may be formed.

The shock absorbing member 15 shown in FIG. 2 is formed by a plate member. The circumferential direction of two half-cut members 16 and 17 having a semicircular cross-section is continuously increased from a front end a to a rear end b. Flat strip-shaped flanges 1 extending in the axial direction at both ends
8 and 19, and the half members 16 and 17 are arranged so as to form a hollow inside, and the flanges 18 and 19 are provided.
These are welded to each other, and the amount of energy absorption can be increased by the flanges 18 and 19.

The shock absorbing member 20 shown in FIGS.
Flat band-shaped flange 1 of shock absorbing member 15 shown in FIG.
Corrugated flange 2 extending in the axial direction instead of 8, 19
2, the half members 23 and 24 are aligned so as to form a hollow inside, and the flanges 21 and 22 are welded to each other. When the shock compression load is applied while increasing the absorption amount, the corrugated flange 2
Due to the shapes of 1 and 22, the entire length can be reliably and smoothly reduced (reduced).

The shock absorbing member 25 shown in FIG. 6 is formed by a plate member. The two circumferentially opposite end portions of two half cut members 26 and 27 having a semicircular cross section whose radius gradually increases from the front end a to the rear end b. And corrugated flanges 28, 29 extending in the axial direction.
The half members 26 and 27 are joined so as to form a hollow inside, and the flanges 28 and 29 are welded to each other.

The shock absorbing member 30 shown in FIG. 7 is formed by plate members, each of two half-cut members 31 and 32 having a semi-circular cross section whose radius gradually increases from the front end a to the rear end b. A small-diameter portion 33 is integrally formed therebetween, and corrugated flanges 34 and 35 extending in the axial direction are provided at both circumferential ends of the half members 31 and 32, respectively. And the flanges 34 and 35 are welded together.

The shock absorbing members 25 and 30 shown in FIGS.
Are flanges 28, 29 and 34, 35 as described above.
The energy absorption amount is increased, and the shape of the corrugated flanges 28, 29 and 34, 35 and the radius thereof are increased stepwise from the front end a to the rear end b when the impact compression load is applied, or The contraction (reduction) of the entire length is more reliably and smoothly performed by the small diameter portion 33. The "semicircular cross section" in the shock absorbing members 10, 15, 20, 25 and 30 of the present invention shown in FIGS.
Include a so-called Hat shape.

In the present invention, the shock absorbing member 1
When manufacturing 0, 15, 20, 25 and 30, the shock absorbing members 10, 15, 20, 25 and 30 are required as molds in all vehicles to which the shock absorbing members are applied. 3 and the maximum value of the total length in the axial direction (for example, S1 + S2 in the shock absorbing member 15 shown in FIG. 2, and FIG. 3).
5 to S3 + S4 + S5 in the shock absorbing member 20 shown in FIG.
Is prepared, and a material (plate member) having a size and a plate thickness required for the target vehicle is placed in the appropriate position of the die (for example, in the shock absorbing member 15, S1 in FIG. S2
(The position of S3 in FIGS. 3 and 5 for the shock absorbing member 20). By this method, 1
A set of molds can accommodate many specifications for the shock absorbing member.

[0015]

The impact absorbing member for a vehicle according to the present invention is characterized in that the diameter thereof is continuously increased from the front end to the rear end by a plate member so as to form a hollow substantially frusto-conical shape. According to the invention of 1 and the plate member, two half-sectioned members having a semicircular cross-section which continuously increase in cross section from the front end to the rear end are formed so as to form a hollow inside, and the mating surfaces are welded. A second invention characterized by the fact that:
The plate member is characterized in that two half-section members having a semi-circular cross section whose radius is gradually increased from the front end to the rear end are formed so as to form a hollow inside, and the mating surfaces are welded. Therefore, in the first invention, by being formed into a substantially frusto-conical shape, even when the overall length is lengthened, it does not bend due to an impact compressive load and reduces while giving appropriate resistance. And the amount of energy absorption can be increased.

According to the second aspect of the present invention, the cross-sectional area is continuously increased from the front end to the rear end.
It can be reduced while giving an appropriate resistance, the amount of energy absorption can be increased, and the fabrication is facilitated by welding the two half members together. In the third aspect, the radius is increased stepwise from the front end to the rear end, so that even when the overall length is increased, it is possible to reduce the size without giving an appropriate resistance without bending by an impact compressive load. , While increasing the amount of energy absorption,
Shrinking (reducing) of the entire length is more reliably and smoothly performed, and furthermore, manufacturing is facilitated by welding the two half members together.

Further, according to the method of manufacturing a vehicle shock absorbing member according to the present invention, the size of the semicircular cross section from the front end to the rear end of the shock absorbing member required for all vehicles to which the vehicle shock absorbing member is applied is provided. A mold having the minimum value and maximum value of the height and the maximum value of the total length in the axial direction is prepared, and a material having the size and plate thickness required for the target vehicle is formed by the appropriate position of the mold. It is not only possible to mold materials of various sizes by using one set of molds properly, but also to have no vertical wall part as in the past,
Materials having different thicknesses can be molded by one set of molds, and eventually, one set of molds can cope with many specifications of the shock absorbing member.

In the above embodiment, a flat strip-shaped flange extending in the axial direction is provided at both circumferential end portions of the two half members, and the two half members are welded through the flange. There is an effect that the amount of energy absorption can be increased.

In the other embodiment, corrugated flanges extending in the axial direction are provided at both ends in the circumferential direction of the two half members, and the two half members are welded through the flanges. In addition to increasing the amount of energy absorption, the shape of the corrugated flange has the effect of reliably and smoothly reducing (reducing) the entire length when subjected to an impact compression load.

Further, in the above-mentioned other embodiment, a small diameter portion is integrally formed between each step of two half-section members having a semi-circular cross section whose radius is gradually increased, so that shock absorption is particularly achieved. Combined with the stepwise increase of the radius from the front end to the rear end of the member, the small diameter portion has the effect of more reliably and smoothly reducing (reducing) the entire length.

[Brief description of the drawings]

FIG. 1 is a front view showing a first embodiment of a shock absorbing member of the present invention, and showing an upper half thereof in cross section.

FIG. 2 is a front view showing an upper half of the shock absorbing member according to a second embodiment of the present invention in cross section.

FIG. 3 is a front view showing a third embodiment of the shock absorbing member of the present invention, and showing an upper half thereof in cross section.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

FIG. 5 is a perspective view showing a method for manufacturing a shock absorbing member according to a third embodiment of the present invention.

FIG. 6 is a front view showing a fourth embodiment of the shock absorbing member of the present invention.

FIG. 7 is a front view showing a fifth embodiment of the shock absorbing member of the present invention.

FIG. 8 is a diagram showing the relationship between the load of the shock absorbing member and the amount of contraction (reduction).

FIG. 9 is a perspective view showing an example of a conventional shock absorbing member.

FIG. 10 is a perspective view showing another example of a conventional shock absorbing member.

[Explanation of symbols]

10, 15, 20, 25, 30 Impact absorbing member of the present invention 11, 12, 16, 17, 23, 24, 26, 27, 3
1, 32 half cut member 13 mating surface 18, 19 flat band plate flange 21, 22, 28, 29, 34, 35 corrugated flange 33 small diameter part a front end of shock absorbing member b rear end of shock absorbing member
α Taper angle.

Claims (7)

[Claims] An impact absorbing member for a vehicle, wherein the diameter is continuously increased from a front end to a rear end by a plate member to form a hollow substantially frustoconical shape. 2. A plate member is used to join two half-sectioned members having a semicircular cross-section that continuously increase in cross section from the front end to the rear end so as to form a hollow inside, and weld the mating surfaces. An impact absorbing member for a vehicle, comprising: 3. A plate member is used to join two half-section members having a semicircular cross section whose radius is gradually increased from the front end to the rear end so as to form a hollow inside, and welding the mating surfaces. An impact absorbing member for a vehicle, comprising: 4. A flat strip-shaped flange extending in the axial direction is provided at both circumferential ends of the two cut members, and the two cut members are welded through the flanges. The vehicle impact absorbing member according to claim 3. 5. A wavy flange extending in the axial direction is provided at both circumferential ends of the two cut members, and the two cut members are welded via the flanges.
Or the shock absorbing member for vehicles according to claim 3. 6. A method according to claim 3, wherein a small-diameter portion is integrally formed between each step of the two half-section members having a semicircular cross section having a stepwise increasing radius. Shock absorbing member for vehicles. 7. A minimum value and a maximum value of a size of a semicircular cross section from a front end to a rear end of a shock absorbing member required for all vehicles to which the vehicle shock absorbing member is applied, and an axial center direction. A method of manufacturing a shock absorbing member for a vehicle, comprising preparing a mold having a maximum value of the entire length, and molding a material having a size and a plate thickness required for a target vehicle at the appropriate position of the mold. Method.