JPH10181630A - Pipe structure for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide pipe structure for a vehicle facilitating assembly and reducing cost by pressing a pipe member axially to form flanges, projecting radially outward, at the pipe member. SOLUTION: A pipe member 20 constituting a cross member of a vehicle frame is provided with flanges 22 of U-shape cross section formed by applying press working to both ends, and assembled to a side member 1 and a reinforcing side member 2. In this case, after inserting the pipe member 20 into holes 25, 26 of the side member 1 and reinforcing side member 2, the periphery of the tip of the pipe member 20 is welded to the side member 1, and the peripheries of the flanges 22 are welded to the periphery of the reinforcing side member 2 to fit the pipe member 20. The diameter of the flange 22 is to be 1.3-1.4 times as large as the outer diameter (d) of the pipe member 20. Press working can therefore be applied without hindrance, and weld length of the flange 22 can be made large so as to lower stress of a weld part, thereby improving rigidity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle pipe structure such as a cross member of a vehicle frame.

[0002]

2. Description of the Related Art Conventionally, a cross member is attached to a side member of a vehicle frame, and a reinforcing side member 2 is attached to a side member 1 having a U-shaped cross section as shown in FIGS. 7 (a) and 7 (b). Welding 3 and inserting a cross member 6 made of a pipe into holes 4 and 5 formed in the side member 1 and the reinforcing side member 2, and attaching the cross member 6 to the side members 1 and 2, Is going.

[0003]

By the way, in order to facilitate the assembling of the cross member 6 at the time of mounting, the diameter D of the holes 4 and 5 of the side members 1 and 2 should be adjusted to the outer diameter d of the cross member 6. , Ie, D = d + 2
The hole diameter is set so that

[0004] However, if the hole diameter is set in this manner, a gap is generated at a welded portion with the cross member 6, and a welding defect is easily generated. Further, the cross member 6 assembled to the holes 4 and 5 has a problem that positioning cannot be performed because the cross member 6 is movable in the axial direction.

In order to cover this weak point, a reinforcing patch 9 is attached to the cross member 6 by welding 10 in advance.
The reinforcing patch 9 is welded to the reinforcing side member 2 11
The reinforcing patch 9
However, the number of parts and the number of welding points increase, and the weight and cost increase.

An object of the present invention is to solve the above-mentioned problems and to provide a pipe structure for a vehicle which can be easily assembled and can reduce the cost.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, a pipe material is press-formed in an axial direction to form a flange projecting radially outward on the pipe material. This is a vehicle pipe structure.

According to a second aspect of the present invention, the flange is formed near both ends of the pipe member constituting the cross member.
It is a pipe structure for vehicles described.

According to a third aspect of the present invention, there is provided the pipe structure for a vehicle according to the first or second aspect, wherein the outer diameter of the formed flange is 1.3 to 1.4d, which is the outer diameter d of the pipe material.

According to a fourth aspect of the present invention, there is provided the pipe structure for a vehicle according to any one of the first to third aspects, wherein the flange is formed to be bent in a U-shaped cross section.

According to a fifth aspect of the present invention, there is provided the pipe structure for a vehicle according to any one of the first to third aspects, wherein the flange is formed so as to have a flared cross section.

According to a sixth aspect of the present invention, there is provided the vehicle pipe structure according to any one of the first to third aspects, wherein the flange is formed to have a bulge-like diameter.

The invention according to claim 7 is the vehicle pipe structure according to any one of claims 2 to 6, wherein a pipe member is inserted into a hole of the cross member, and a flange thereof is welded to the cross member around the hole.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

In FIG. 1 (a), reference numeral 20 denotes a pipe member constituting a cross member. Both ends (or ends) of the pipe member are subjected to press working to form a flange having a U-shaped cross section as shown in FIG. 1 (b). 22 is formed.

The pipe member 20 on which the flange 22 is formed
As shown in FIG. 2, after inserting into the holes 25 and 26 of the side member 1 and the reinforcing side member 2, the periphery of the tip of the pipe member 20 is welded 23 to the side member 1 and the periphery of the flange 22 is reinforced. It is attached around the side member 2 by welding 24.

In this case, the holes 26 of the reinforcing side members 2
Should be a hole diameter that does not allow the flange 22 to pass through.
Also, since the hole 25 of the side member 1 has no problem even if the hole diameter is such that the pipe member 20 can be fitted tightly, the assembly can be performed accurately and the outer periphery of the flange 22 can be welded by welding 24.
Therefore, the centering at the time of welding can be accurately performed.

The flange 22 has a diameter of 1.3 to 1.4 with respect to the outer diameter d of the pipe member 20, so that the press working is not hindered and the welding length when the flange 22 is welded. Can be increased, so that the stress at the welded portion can be reduced. In addition, by the flange processing, the welded joint becomes an arc shape, the stress concentration is reduced, and the welded joint can be separated from the maximum stressed portion. Further, the surface rigidity of the mounting portion can be improved by approaching the bending radius of the side member 1.

FIG. 3 shows details of the press working of the flange 22 of the pipe member 20. In the figure, 3
0 is an upper mold, 31 is a lower mold, and upper and lower molds 30 and 31 are used to remove the pipe material 20 of the pipe material 20 except for the flanged portion 21.
When the outer and inner peripheries (not shown) are constrained and a compressive load is applied to the pipe member 20 by a press machine, the unconstrained flange processing portion 21 buckles to form the flange 22. The edges 34, 35 of the restraining holes 32, 33 for restraining the pipe material 20 of the upper mold 30 and the lower mold 31 are formed in a radius of several millimeters (specifically, 2 to 5 mm).
At the time of press molding of No. 1, buckling stress was not concentrated on this portion.

In this flange processing, STKM13
A pipe material 20 equivalent to A (φ50.8 mm outer diameter, wall thickness t = 2.6 mm), and the maximum flange outer diameter is φ = 70.1 mm
When the outer diameter of the flange is 1.4 times or more, not only the axial symmetry of the flange deteriorates, but also the flange diameter hardly increases and the shape deteriorates, which is not preferable. When the outer diameter is 1.3 or less, the length of the flanged portion 21 is short, so that the flanged portion becomes difficult and stress cracking occurs, which is not preferable. Therefore, the outer diameter of the flange is 1.3 to 1.4 of the outer diameter d of the pipe member 20.
It turned out that double was good. Further, the wall thickness of the pipe (t = 2.
6 mm), the above condition changes, but it was found that the above condition was satisfied if d / t was substantially constant.

4 to 6 show another embodiment of the present invention.

FIG. 4A shows a pipe member 20 having a flange 22a formed at an end thereof.

FIG. 4B shows a structure in which a flange 22 is formed near the pipe member 20 and a member 40 is caulked and supported between the flanges. For example, the member 40 is used as a brake pedal, Rotating fulcrum is pipe material 20
It is configured to be supported by.

FIGS. 5A and 5B show the flange 42.
5A shows an example in which the shape is formed in a flare shape. FIG. 5A shows an example in which the shape is formed at an end of the pipe material 20, and FIG. This flare processing can be performed by forming a flare-shaped receiving groove in the mold.

FIGS. 6A and 6B show the structure of the flange 44.
FIG. 6 (a) shows an example in which the shape of is formed in a bulge shape.
FIG. 6B shows an example in which the curvature of the bent portion 45 is small and the flange 44 is formed in a mountain-shaped cross section, and FIG. is there.

In the embodiment shown in FIGS.
0 is used as the cross member, the flanges 42, 4
4 is located inside the reinforcing side member 2 and its hole 26
When the pipe material 20 is centered when
Can be guided, the centering at the time of assembling becomes easy, the concentration of local stress can be prevented, and the weldability can be improved.

[0027]

According to the present invention, the following effects can be obtained.

(1) By forming the flange directly on the pipe material, the conventional reinforcing patch can be eliminated, the number of welding points can be reduced, and the weight and cost can be reduced.

(2) Since the hole diameter of the reinforcing cross member can be increased, the workability of inserting the cross member can be improved.

(3) Since the gap between the welds can be reduced, the strength and workability of the weld can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a use state of the present invention.

FIG. 3 is an explanatory view for performing flange processing in the present invention.

FIG. 4 is a diagram showing another embodiment of the present invention.

FIG. 5 is a diagram showing still another embodiment of the present invention.

FIG. 6 is a diagram showing still another embodiment of the present invention.

FIG. 7 is a diagram showing a conventional example.

FIG. 8 is a diagram showing another conventional example.

[Explanation of symbols]

 20 Pipe material 22 Flange

Claims (7)

[Claims] 1. A pipe structure for a vehicle, wherein a pipe material is press-formed in an axial direction, and a flange projecting radially outward is formed on the pipe material. 2. The pipe structure for a vehicle according to claim 1, wherein the flange is formed near both ends of the pipe member forming the cross member. 3. The pipe structure for a vehicle according to claim 1, wherein the outer diameter of the formed flange is 1.3 to 1.4d, which is the outer diameter d of the pipe material. 4. The vehicle pipe structure according to claim 1, wherein the flange is formed to be bent in a U-shaped cross section. 5. The vehicle pipe structure according to claim 1, wherein the flange is formed so as to have a flared cross section. 6. The vehicle pipe structure according to claim 1, wherein the flange is formed to have a bulge-like diameter. 7. A pipe member is inserted into a hole of the cross member,
The vehicle pipe structure according to any one of claims 2 to 6, wherein the flange is welded to a cross member around the hole.