JP3395712B2 - Shield gas supply nozzle for welding - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a welding shield gas supply nozzle used in a laser welding apparatus.

[0002]

2. Description of the Related Art FIG. 4 shows an example of a conventional welding shield gas supply nozzle. In FIG. 4, a conventional welding shield gas supply nozzle 21 is provided with a cylindrical nozzle hole 22 having a flat opening shape, and the shield gas sprayed from the flat cylindrical nozzle hole 22 is applied to the welding portion W. On the other hand, it was supplied from one direction.

When a method of injecting the shield gas into the welding portion from only one direction using such a flat cylindrical shield gas supply nozzle, since the shield gas is injected from one direction, a uniform welding surface can be obtained. There is a problem that you cannot do it.

However, if a large number of shield gas supply nozzles are used and a plurality of nozzles are arranged so as to surround the welded portion, it is possible to evenly supply the shield gas to the entire circumference of the welded portion. In most cases, it is usually difficult to secure a space for arranging a plurality of nozzles near the welded portion.

Such a problem can be solved by using a ring-shaped shield gas nozzle. Japanese Patent Laid-Open No. 4-
As disclosed in Japanese Patent No. 333388 (Prior Art 1), as shown in FIG.
There is described a laser welding processing head in which a center gas nozzle 31 that ejects an assist gas coaxially with a laser beam 30 has a circular opening shape and a ring-shaped shield gas nozzle 32 is integrally provided around the opening shape.

Further, Japanese Patent Laid-Open No. 9-70682 (Prior Art 2) shows an example in which a shield gas nozzle is used in combination with a laser welding apparatus, as shown in FIGS. 6 (a) and 6 (b). , An example in which the shape of the gas outlet of the nozzle is a continuous circumferential slit 41, and an example in which small holes 42 are circumferentially arranged are described.

By using such a continuous circumferential slit and a ring-shaped shield gas supply nozzle in which small holes are circumferentially arranged, the welded portion by the laser light is uniformly shielded from the periphery thereof. Can blow gas.

[0008]

However, since the shield gas nozzle 32 of the prior art example 1 is integrated with the center gas nozzle 31 as a laser welding processing head, the structure is complicated and the main body of the laser welding apparatus. Apart from, the relative position of the shield gas nozzle with respect to the beam weld W cannot be adjusted.

In this respect, the prior art 2 uses the laser welding apparatus in combination with the shield gas nozzle, and therefore the structure is simplified as compared with the prior art 1.

Still, in the annular shield gas nozzle used in the second prior art, for example, as shown in FIG. 7, an opening 45 having an inner peripheral surface along the converging shape of the laser beam 44 is provided at the center of the nozzle body 43. , Around it, the opening 45
Nozzle hole 4 that is coaxial with
Since a structure having 6 is used, the structure of the nozzle is quite complicated.

In these prior art examples, an annular nozzle is used as the shield gas nozzle, and the shield gas is sprayed downward from the slits or small holes of the nozzle toward the welded portion. When the shield gas is blown downward, an accompanying flow of air is generated in the central passage of the nozzle, welding defects such as holes are generated, and surrounding air may be entrained, resulting in insufficient shielding. Pointing out the problem.

[0012] Certainly, the shielding of the welded portion does not necessarily need to spray the shield gas onto the welded portion, but by supplying the shield gas to the welded portion, an atmosphere for shielding the welded portion from the atmosphere is formed around. Must be.

It is an object of the present invention to provide a welding shield gas supply nozzle capable of sufficiently shielding a welded portion with a simple structure using only one pipe.

[0014]

In order to achieve the above object, in a welding shield gas supply nozzle according to the present invention, there is provided a welding shield gas supply nozzle having a pipe section and a nozzle section. The nozzle section is formed by partitioning into a single pipe whose one end is closed,
The pipe part is a part of the pipe that supplies the shield gas sent from the outside to the nozzle part, and the nozzle part injects the supplied shield gas to form a shield atmosphere of the outside air in the welded part of the workpiece. Part of the pipe, and the pipe that follows the pipe part has a double or more multiple spiral shape.
It is bent into a cylinder and has a gas outlet on its inner peripheral surface.
There is .

[0015]

Further, the pipe unit is bracket mounted to the body of the laser welding apparatus is mounted on a portion thereof, it adjusts the relationship position of the nozzle unit with respect to the laser beam by a portion of the bending deformation of at least the pipe section is there

Further , the nozzle portion has multiple spirals.
By changing the diameter of the arc part of each stage of the laser
This is in line with the beam converging shape.

Further , the gas outlet is provided in each of spirals.
The size, opening position, and opening shape of the spout differ for each step.
Control the flow rate and direction of the shield gas to
It is designed to do more proper

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, a welding shield gas supply nozzle 1 according to the present invention has a pipe portion 2 and a nozzle portion 3, and the pipe portion 2 and the nozzle portion 3 are made of a single metal whose one end is closed. The pipe 4 is formed by partitioning.

The pipe portion 2 is a pipe portion for supplying the shield gas blown from the outside to the nozzle portion 3, and a bracket 5 attached to the machine body of the laser welding apparatus is attached to a part of the pipe portion 2. .

The nozzle portion 3 is a portion of the pipe that injects the supplied shield gas to form a shield atmosphere of the outside air in the welded portion of the work, and has an arc shape in a certain range of the tip portion of the pipe that follows the pipe portion 2. A shield gas ejection port 6 is opened on the inner peripheral surface of a pipe which is bent and deformed into a circular arc.

When forming the nozzle part 3, as shown in FIG. 1, the end of the pipe part 2 is bent at an angle close to a right angle, leaving a certain range of the tip part of the pipe 4 whose end part is blocked, Further, a certain range of the tip portion is bent and deformed in an arc shape, and a shield gas ejection port 6 is opened on the inner peripheral surface of the pipe bent in an arc shape.

In this embodiment, a slit is opened as the gas ejection port 6, but not limited to the slit, it is possible to open a large number of small holes.

FIG. 2 shows an example of the laser welding apparatus 7 equipped with the shield gas supply nozzle 1 according to the present invention. In the figure, the bracket 5 of the pipe portion 2 is attached to a part of the machine body of the laser welding device 7, and the pipe portion 2 is appropriately bent and deformed to place the nozzle portion 3 at a position near the work on which the laser light 8 is focused. The laser beam 8 is received inside the arc-shaped pipe, and the nozzle 3 is installed in a predetermined posture.

In FIG. 2, the laser light transmitted by the optical fiber 9 is incident on the laser welding emission part 10 of the laser welding device 7, and the laser light 8 emitted from the laser welding emission part 10 is emitted from the nozzle part 3. Passing through the arc of the pipe,
The laser light 8 is focused and irradiated on the welded portion of the work 11.

On the other hand, a shield gas such as argon or nitrogen is introduced into the pipe portion 2 of the welding shield gas supply nozzle 1, and the shield gas is supplied from the gas ejection port 6 of the nozzle portion 3 in the inner circumferential direction of the arc of the pipe. Is injected into the air, and a certain range including the welded portion W is shut off from the outside air, and the work is welded under the shutoff atmosphere of the outside air.

In this example, the first work 11 and the second work 12 superposed on the back surface of the work 11 are welded. In the present invention, it is desirable that the arc shape of the pipe 4 of the nozzle portion 3 formed by bending the pipe be as close to a perfect circular shape as possible, but the nozzle portion 3 is processed into a single arc shape. However, if necessary, the pipe 4 may be bent into a double or multiple spiral shape and a gas ejection port 6 may be opened on the inner peripheral surface thereof, as shown in FIG. .

Since the nozzle portion 3 is formed by bending the pipe, the diameter of the arc can be freely set. When bending the pipe 4 into the multiple spirals of the nozzle part 3, FIG.
As shown in FIG. 5, the diameter of the arc portion of each step of the multiple spirals can be made different so that the overall shape of the laser beam 8 can be adjusted.

In this example, the size, opening position, and opening shape of the spout are made different for each spiral of each stage to control the flow rate and direction of the shield gas to more appropriately shield the welded part and to perform welding. Roughness and discoloration due to oxidation of the surface of the part can be prevented.

[0030]

As described above, according to the present invention, a shield gas supply nozzle is obtained by bending a pipe into an arc shape and opening a gas ejection port by a slit or a hole on the inner peripheral surface side. , As in the past, even if the shield gas is not necessarily blown to the welded portion, by setting the diameter of the arc and the opening position and the opening direction of the ejection port formed on the arc surface of the pipe, the outside air is not entrained. An optimum shield atmosphere of the outside air can be formed around the weld.

Further, according to the present invention, by processing the pipe into a multiple spiral shape, it is possible to more effectively form the shield atmosphere of the outside air by aligning the nozzle portion with the converging shape of the laser beam. According to the present invention, a shield gas supply nozzle including a pipe portion and a nozzle portion can be easily obtained only by bending and drilling a pipe.

The present invention uses only one pipe,
The structure is simple, and even when it is assembled to the body of the beam welding device, the relative position of the nozzle part with respect to the laser beam can be changed by bending at least a part of the piping part or by performing bending work in advance. It can be adjusted appropriately.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, in which (a) is
The front view of the welding shield gas supply nozzle, (b),
(A) is a BB line arrow view, (c) is a CC sectional view taken on the line (b).

FIG. 2 is a diagram showing a main part of a beam welding apparatus equipped with a welding shield gas supply nozzle according to the present invention;

FIG. 3 is a view showing another embodiment of the welding shield gas supply nozzle according to the present invention.

FIG. 4A is a diagram showing an example of a conventional welding shield gas supply nozzle, and FIG. 4B is a diagram showing the shape of a nozzle hole.

FIG. 5 is a diagram showing a laser welding processing head described in Prior Art 1;

6 (a) and 6 (b) are diagrams showing the outlet of the shield gas shown in the second prior art.

FIG. 7 is a configuration diagram of a shield gas supply unit of the laser welding apparatus shown in the second prior art.

[Explanation of symbols]

1 Shield gas supply nozzle 2 piping section 3 Nozzle part 4 pipes 5 bracket 6 spouts 7 Laser welding equipment 8 laser light 9 optical fiber 10 Laser welding emitting part 11 First work 12 Second work

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B23K 26/00-26/073

Claims (4)

(57) [Claims] 1. A shield gas supply nozzle for welding having a pipe part and a nozzle part, wherein the pipe part and the nozzle part are partitioned and formed in a single pipe with one end blocked. Yes, the pipe part is the part of the pipe that supplies the shield gas sent from the outside to the nozzle part.The nozzle part injects the supplied shield gas to form the shield atmosphere of the outside air in the welded part of the workpiece. The part of the pipe to be connected, and the pipe that follows the piping part is doubled or more
Bending into multiple spirals, and gas on its inner peripheral surface
A welding seam characterized by having an ejection port
Liquid gas supply nozzle. Wherein said pipe section is a bracket to be mounted on the machine body of the laser welding apparatus is mounted on a portion thereof, it adjusts the relationship position of the nozzle unit with respect to the laser beam by a portion of the bending deformation of at least the pipe section The shield gas supply nozzle for welding according to claim 1, wherein the shield gas supply nozzle is for welding. 3. The contracting device according to claim 1, wherein the nozzle portion is formed so that the diameter of the arc portion of each step of the multiple spirals is made different and the shape of the laser beam is conformed as a whole.
The shield gas supply nozzle for welding according to claim 1 . 4. The gas outlet is provided for each stage of the spiral.
The size, opening position and opening shape of the spout
Weld zone sealing by controlling the flow rate and direction of the field gas
Claim is characterized in that it is adapted to perform more appropriate
The shield gas supply nozzle for welding according to 1.