JPH0740058A - Manufacture of eye joint - Google Patents

Abstract

PURPOSE:To prevent generation of spatter in the eye part and tube part, and prevent the defective welding by forming the bead on a base part on the insertion side to the eye part of a tube, and executing the projection welding while press-fitting the bead and the circumferential edge of the entrance of a tube connecting hole in a linear contact manner. CONSTITUTION:A bead 7 is formed on the base part on the insertion side to an eye part 1 of a tube 5. The bead 7 is formed by the bulge working or the bead placement, and the insertion side to a tube connecting hole 3 of the bead 7 is tapered. The tip of the metallic tube 5 is partially inserted into the tube connecting hole 3 formed on the circumferential surface of the eye part 1, and the tube 5 is held by a cylindrical or two-split cylindrical lower electrode 11 while the bead 7 and the circumferential edge of the entrance of the tube connecting hole 3 are pressed, and the eye part 1 is held by an arch-shaped upper electrode to charge the space between the tube 5 and the eye part 1 while being pressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal eye portion and a pipe connecting hole formed in the peripheral surface of the eye portion, and the tip of the metal pipe portion is partially inserted and welded on the insertion base side. The present invention relates to a method for manufacturing an eye joint to be joined. This type of eye joint is used for connecting a device body and a flexible hose, for example, in a fuel pipe of an automobile.

[0002]

2. Description of the Related Art Eye joints have been manufactured from solid metal materials by cutting, etc.
No.), the following manufacturing methods are becoming mainstream from the viewpoint of material and man-hour reduction.

For example, when manufacturing the eye joint 1 as shown in FIG. 1, as shown in FIG.
And the tip of the metal pipe part 5 is partially inserted into the pipe connection hole 3 formed in the peripheral surface of the eye part 1 to the insertion source side,
It was manufactured by welding and brazing in a furnace. Note that FIG.
H, which can be placed at, is a rubber hose.

[0004]

However, in the case of joining by brazing in a furnace, the brazing filler metal is set at the insertion source of the pipe and carried into the brazing furnace, and further, the eye joint after brazing. You need a person to take out. In addition, the time required to complete the brazing (in-furnace transportation time) is about 1 hour.

In view of the above, it is an object of the present invention to provide a method for manufacturing an eye joint which can reduce manpower and can shorten the production time.

[0006]

In order to solve the above-mentioned problems, the inventors of the present invention have made efforts in earnest development, and conventionally, resistance welding involves spattering on a pipe or an inner peripheral surface of an eye portion. It becomes a factor that obstructs the flow path), and melting does not proceed sufficiently and welding defects (joint strength, insufficient seal, etc.) are likely to occur, so it is not paid much attention as being unsuitable for manufacturing eye joints. Focusing on resistance welding, the inventors have come up with a method for manufacturing an eye joint having the following configuration.

A method for producing an eye joint made of metal and an eye joint in which the tip of the metal pipe portion is partially inserted into a pipe connection hole formed in the peripheral surface of the eye portion and welded at the insertion source side. In, the bead is formed at the base of the insertion side of the pipe part to the eye part, and the insertion side of the bead into the pipe connection hole is tapered, and / or the inlet side peripheral edge of the pipe connection hole is tapered. It is characterized in that a lip is formed and the front bead and the peripheral edge of the inlet of the pipe connection hole are line-contact pressure-welded while resistance welding is performed to join the eye portion and the pipe portion.

[0008]

EXAMPLES The present invention will now be described in detail based on examples. The same parts as those in the above-described example are designated by the same reference numerals, and the description thereof will be omitted in whole or in part.

(1) The metal eye portion 1 and the pipe connecting hole 3 formed in the peripheral surface of the eye portion 1 are partially inserted at the tip of the metal pipe portion 5 and welded together at the insertion base side. The manufacturing method of the eye joint is assumed.

Here, the metal material for forming the eye portion and the pipe portion is not particularly limited as long as it can be resistance welded, such as steel, brass, aluminum, etc. Normally, the same kind of material that can be resistance welded to each other is used. .

The eye portion is usually prepared by cutting or forging from a solid round bar. However, the pipe connecting hole on the peripheral surface of the eye portion is formed by cutting. Also, the pipe part is
Prepare by cutting ordinary pipe material.

(2) Then, as shown in FIG. 3, a bead 7 is formed at the base portion of the pipe portion 5 on the side where the pipe portion 5 is inserted into the eye portion 1. The beads 7 are formed by bulging or beading. At this time, the formation position of the bead 7, that is,
For example, the tip insertion length of the pipe part is 8 mmφ
In the case of × 1 mmt, it is set to 1 to 5 mm (hereinafter, all set numerical values assume this case). In addition, the fitting state of the pipe connection hole 3 and the pipe portion 5 is set to be a clearance fit.
The gap is usually in the range of 0.1 to 0.3 mm. This is because if the pipe portion 5 and the inner peripheral surface of the pipe connection hole 3 come into contact with each other during resistance welding, the initial welding resistance decreases, which is not desirable.

At this time, the insertion side of the bead 7 into the pipe connection hole 3 is tapered. This taper angle α
Is 30 ° to 75 °. If the angle is less than 30 ° or more than 70 °, it is difficult to obtain the required electric resistance for melting the required metal at the initial stage of welding.

If the bead 7 is not tapered,
Alternatively, as shown in FIG. 5, a tapered lip (projection) 9 may be formed at the inlet side peripheral edge of the pipe connection hole 3 in addition to the taper shape. The inclination angle β of the tapered lip at this time is 30 ° to 75 ° as in the case of the bead. If it is less than 30 °, it is difficult to obtain the electric resistance value required for the required metal melting at the initial stage of welding, and if it exceeds 70 °, the tip is too thin and buckles and deforms with a weak pressing force.
It is difficult to obtain the electric resistance value required for melting the required metal.

(3) Then, the tip of the metal pipe part 5 is partially inserted into the pipe connection hole 3 formed on the peripheral surface of the eye part 1 to press the bead 7 and the inlet peripheral edge of the pipe connection hole 3. While the pipe portion 5 is held by the lower electrode 11 having a tubular shape or a split tubular shape, which is arranged as shown in FIG. 7, and the eye portion 1 is held and pressed by the upper electrode 13 having an arch shape, the pipe portion 5 5 and the eye part 1 are energized. The lower electrode 11 and the upper electrode 13 are assembled in a resistance welding machine (not shown). In this way, the eye portion 1 and the pipe portion 5 are welded and joined by resistance welding to manufacture an eye joint.

At this time, the applied pressure is 200 to 400 kg.
f, and the current is 15 to 20 kA.

In this case, at the beginning of welding, the bead 7
Since the line and the inlet periphery of the pipe connection hole 3 are in a line contact pressure contact state, the initial contact resistance increases, and the pipe connection hole 3
The temperature of the joint between the bead 7 and the peripheral edge of the inlet rapidly rises, and the contact portion softens uniformly over the entire circumference. Then, the contact portion is deformed by the applied pressure and the contact resistance is reduced, but heat generation is assisted by the increase in the resistance of the base metal itself accompanying the temperature rise,
The joint reaches a molten state. At that time, due to the pressing force applied to the joint, it deforms in a close contact state as shown in FIG. 4 or FIG.

[0018]

The method of manufacturing the eye joint of the present invention has the following functions and effects due to the above-mentioned constitution.

At the initial stage of welding, the bead and the inlet peripheral edge of the pipe connection hole are in a line contact pressure contact state, so that uniform resistance welding can be performed over the entire circumference of the joint, and spatter is generated on the inner peripheral surface of the eye or pipe. In addition, there is no risk that the welding will not occur sufficiently and the welding will not proceed sufficiently (welding strength, insufficient sealing, etc.).

Further, as compared with the case of manufacturing by conventional brazing in a furnace, manpower required for welding can be reduced, and moreover,
Welding time is also in seconds, and production time is short. Furthermore, automation is easier than brazing in a furnace.

[Brief description of drawings]

FIG. 1 is an overall perspective view of an eye joint to which the present invention is applied.

FIG. 2 is a cross-sectional view of the usage state of the eye joint.

FIG. 3 is a partial cross-sectional view at the start of resistance welding in an example of the manufacturing method of the present invention.

FIG. 4 is a partial sectional view of the same after completion of resistance welding.

FIG. 5 is a partial cross-sectional view at the start of resistance welding in another example of the manufacturing method of the present invention.

FIG. 6 is a partial sectional view of the same after resistance welding is completed.

FIG. 7 is an electrode layout diagram of resistance welding in the manufacturing method of the present invention.

[Explanation of symbols]

 1 Eye Part 3 Pipe Connection Hole 5 Pipe Part 7 Bead 9 Tapered Lip (Projection) 11 Lower Electrode 13 Upper Electrode

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area F16L 41/02

Claims (1)

[Claims] 1. An eye joint of a metal eye portion and a pipe joint hole formed in a peripheral surface of the eye portion, wherein a tip of the metal pipe portion is partially inserted and welded and joined at an insertion source side. In the manufacturing method, a bead is formed on the insertion side base of the pipe part into the eye part, and the insertion side of the bead into the pipe connection hole is tapered, and / or the pipe connection hole. A tapered lip is formed on the inlet side peripheral edge of the pipe, and resistance welding is performed while linearly contacting the bead and the inlet peripheral edge of the pipe connecting hole to join the eye portion and the pipe portion. Manufacturing method of eye joint.