JPH09273519A - Connecting structure of pipe member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase brazing strength by expanding the vicinity of the end part of an inserting pipe in an outer peripheral direction, expanding a projection nearly along to a relative penetrating line formed by the end part and a receiving hole, and to reduce external force acting on a brazing metal by bearing the external force by the projection self so as to obtain high connecting strength. SOLUTION: In the case where the cross sectional part of a connecting structure is compared with a prior art, a part to be brazed is brazed between the side surface of a projection 22 and the outer surface of a hole receiving pipe 11 other than between the inner surface of a prior receiving hole 12 and a guide part 21, and a surface to be brazed is increased sharply. In such above connecting structure, when bending force acts on an inserting pipe 20 as external force, the force does not act at once unlike the prior art on a brazing metal 15 in which the inner surface of the receiving hole 12 is filled. Since firstly the force is transferred from the side surface of the projection 22 to the outer surface of the receiving hole pipe 11, in is possible to avoid concentration of stress which is easily generated on the brazing metal 15 formed on the root of the inserting pipe 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a pipe member suitable as a connecting structure of a tip end portion of a pipe material forming a body of a bicycle or a motorcycle and a steering shaft pipe (steering head pipe) connected thereto. It relates to the bond structure of.

[0002]

2. Description of the Related Art Generally, a pipe material forming a vehicle body and a steering shaft tube are brazed by using a metal brazing in a manner shown in the lower half of FIG. That is, a receiving hole B is formed in the side surface of the receiving hole pipe A forming the steering shaft pipe, and the tip of the insertion pipe C forming the vehicle body frame is inserted therein, and the inner surface of the receiving hole B and the insertion pipe C are inserted. A metal braze E is filled between the outer surface and the outer surface to bond them.

[0003]

However, the receiving hole B and the pipe material C inserted into the receiving hole B only face each other with a narrow surface only on the inner peripheral surface of the receiving hole B, and the area thereof is too small. There is a defect. Further, as shown in FIG. 2, when the axis of the receiving hole B and the axis of the pipe material C intersect, the thickness of the layer of the metal brazing material E becomes uneven, and as a result, the two pipes are joined together. The strength decreased. Further, when a bending force is applied between the two pipes, stress concentrates on the fitted edges of the two pipes, and similarly there is a problem that the joint strength is reduced.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned inconvenience by means of a simple means. A receiving tube having a receiving hole on a side surface and a brazing inserted through the receiving hole. And an insertion pipe to be inserted, and the vicinity of the end portion of the insertion pipe is bulged in the outer peripheral direction to bulge a ridge roughly along the line of penetration formed by the receiving hole and the insertion pipe. The outer surface of the receiving hole tube is brazed and connected. Specifically, the ridges bulged along the substantially cross line are formed to be inclined in the axial direction of the insertion tube, or the shape of the outer surface along the axial direction of the tube has a substantially semicircular shape. While being formed, the inner side surface of the curved portion is formed into a circular surface along the inner surface of the receiving hole pipe. Further, the insertion tube solves the problem by forming a guide portion which is inserted into the receiving hole tube on one side of the substantially continuous linear projection.

[0005]

The projecting bulge formed on the outer surface of the insertion tube is formed so that the outer surface bulges out along the line of penetration formed by the insertion tube and the receiving hole tube in a semicircular shape. Since the side surface of the strip extends along the outer surface of the receiving pipe, the opposite surface thereof becomes the surface to be brazed. In addition, in the connecting portion where the bending stress due to external force tends to concentrate, the side surface of the ridge faces the receiving tube and bears the load, and the inserting tube twists in the receiving hole. No force is applied. When setting the relative position of both pipes prior to brazing work, inserting the guide part into the receiving hole in advance will facilitate the rotation of the insertion pipe, and the relative position such as the phase and depth around the axis will be positioned. It Further, if the ridges are tilted toward the receiving hole tube side and swelled, the distance between the side surface of the ridges and the outer surface of the receiving hole tube becomes closer, and the thickness of the layer for filling the brazing material becomes thinner.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. In FIG. 1, 10 is a bonding structure according to the present invention,
This is a connection structure of the receiving tube 11 and the insertion tube 20. Here
Concretely, the receiving hole pipe 11 is a steel steering shaft pipe which forms the front part of the vehicle body of the motorcycle, and the insertion pipe 20 is inserted into the receiving shaft pipe 11 as the steering shaft pipe and brazed there. The front member of the steel body frame is similar to the receiving pipe 11. That is, as shown in FIG. 2, a receiving hole 12 is formed in the side surface of the receiving hole tube 11, and the insertion tube 20 is inserted therein and fixed by brazing.

Here, as shown in FIG. 2 and subsequent figures, a protrusion 22 is formed at the end of the portion of the insertion tube 20 inserted into the receiving hole 12. That is, the insertion tube 20 bulges in the outer peripheral direction by upset (upset) processing or bulge processing in the vicinity of the end of a circular pipe material made of steel,
The ridge 22 is formed over the entire circumference, and a short circular pipe portion forming the guide portion 21 is left on the end side of the ridge 22.

The shape of the ridge 22 is such that the insertion tube 20 is the receiving hole tube 11
Of the two pipes 11, 20 formed when inserted into the
It is in line with. As a result, when the insertion tube 20 is inserted into the receiving hole 12, the side surface of the ridge 22 is approximately in the receiving hole 12.
It will be parallel to the edge of. That is, the two are the intersection line Z
Since the long lines along the line face each other, brazing between the two is possible. The shape of the protrusions 22 is, as shown in FIG. 2, a case where the insertion tube 20 intersects with the axis of the receiving hole tube 11 at an angle, and a case where the projection tube 22 intersects from an orthogonal direction as shown in FIG. It goes without saying that the shapes of the penetration line Z and the shape of the penetration line Z are different.

As shown in the upper half of FIG. 4, the cross-sectional shape of the ridge 22 is generally a semi-circular outer surface in the axial cross section. It is not an essential requirement that the cross-sectional shape is semicircular, and the shape may be changed to a different shape depending on the application and function. That is, the ridge 2
In order to increase the size of the surface of the No. 2 contacting the hole receiving pipe 11 and to make the thickness of the space filled with the metal brazing uniform, the protrusion 22 is drawn from the position shown by the broken line as shown in FIG. It may be pressed to the 11 side and crushed to form a wide cylindrical surface 22 a along the outer surface of the receiving hole tube 11. At this time, as a reaction, the surface on the opposite side of the receiving hole tube 11, that is, the surface on the pressed side is crushed into a circular shape, and the appearance is made beautiful as a cylindrical surface 22b along the outer surface of the receiving hole tube 11. Things are done.

Next, a method for connecting the receiving tube 11 and the insertion tube 20 in this embodiment will be described. First, prior to brazing, a receiving hole 12 is formed in the receiving hole tube 11, and the insertion tube 2
A ridge 22 is formed at the end of 0. And the insertion tube 2
The guide portion 21 formed at the end portion of 0 is inserted into the receiving hole 12 and is pushed as a guide until the protrusion 22 comes into contact with the edge of the receiving hole 12, and is rotated in the circumferential direction to protrude the protrusion 2.
2 is roughly matched with the crossing line Z. With this, the receiving tube 1
1 and the insertion tube 20, not only the inner peripheral surface of the receiving hole 12,
The side surface of the ridge 22 and the surface of the receiving hole tube 11 facing the outer surface are in contact with each other. Next, a paste-like metal brazing material 15 is attached to the vicinity of the joint surface, or the end portion of the insertion tube 20 is plated with the metal brazing material 15 in advance, and when this is heated, the metal brazing material 15 immediately flows and is When a narrow gap between the peripheral surface and the facing surface is filled and a predetermined temperature is reached, the wax molecules diffuse to the surfaces of the tubes 11 and 20 and adhere to both surfaces.

FIG. 4 shows a cross section of the coupling structure 10 thus obtained in comparison with the conventional one. That is, in this embodiment, the parts to be brazed are not only between the inner surface of the conventional receiving hole 12 shown in the lower half and the guide portion 21, but also on the side surface of the projection 22 and the outer surface of the receiving hole pipe 11. It is understood that there is a significant increase in brazed and brazed surface between. Bonding structure 1 thus obtained
0 is when a bending force acts on the insertion tube 20 as an external force,
The force does not immediately act on the metal brazing filler 15 filling the inner surface of the receiving hole 12 as in the prior art, but is first transmitted from the side surface of the ridge 22 to the outer surface of the receiving hole tube 11, so that it is applied to the base of the insertion tube 20. It is possible to avoid concentration of stress that is likely to occur in a certain metal braze 15. Therefore, a strong coupling strength can be obtained between the two pipes 11 and 20, and particularly when the axis of the receiving hole 12 and the insertion pipe 20 are set at an inclined angle, the receiving hole 12 and the outer surface of the insertion pipe 20 are not connected to each other. If the gaps in are not uniform, the effect is remarkable.

[0012]

As described above, according to the present invention, although the receiving hole tube 11 and the insertion tube 20 are joined by brazing, the brazing strength is provided by providing the protrusions 22. In addition, since the ridge itself bears the external force, the external force acting on the metal brazing is reduced and a high bonding strength can be obtained. Further, it has an effect that only a simple process of forming a ridge corresponding to a continuous line is added to the tube on the inserting side.

[Brief description of drawings]

FIG. 1 is a side view showing a connecting structure of pipe members according to an embodiment of the present invention, specifically, a steering shaft pipe of a motorcycle.

FIG. 2 is a longitudinal sectional view thereof.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 shows a cross-section of a joint, where the upper half is the structure of the present invention and the lower half is the conventional structure.

FIG. 5 is a longitudinal sectional view corresponding to FIG. 2 showing another embodiment.

6 is a view showing the insertion tube in FIG. 5 taken out,
(A) is an external view and (b) is a longitudinal cross-sectional view thereof.

[Explanation of symbols]

10 ... Connection structure of pipe members 11 ... Receiving hole pipe (steering shaft pipe) 12 ... Receiving hole 15 ... Metal braze 20 ... Insertion pipe 21 ... Guide portion 22 ... ・ Ridge 22a ・ ・ ・ Cylindrical surface 22b ・ ・ ・ Cylinder surface along outer surface A ・ ・ ・ ・ Receiving hole tube B ・ ・ ・ ・ Receiving hole C ・ ・ ・ ・ Insertion tube E ··· Metal brazing Z ···

Claims (4)

[Claims] 1. A receiving hole tube having a receiving hole on a side surface thereof, and an insertion tube inserted into the receiving hole and brazed, and a portion near the end of the insertion tube is bulged in an outer peripheral direction to receive the same. A connecting structure for pipe members, in which a ridge substantially bulging along a penetration line formed by a hole and an insertion tube is bulged and the ridge and the outer surface of the receiving hole pipe are brazed and connected. 2. The connecting structure for pipe members according to claim 1, wherein the ridges bulging along the substantially intersecting line are formed to be inclined in the axial direction of the insertion pipe. 3. The projection according to claim 1, wherein the bulge bulged along the substantially penetrating line has a substantially semicircular outer surface along the axial direction of the pipe, and has a curved inner portion. The side surface is a connection structure of pipe members formed in a circular surface along the inner surface of the receiving pipe. 4. The connecting structure for pipe members according to claim 1, wherein said insertion pipe is formed with a guide portion which is inserted into the receiving hole pipe on one side of a substantially continuous linear projection.