JPH0639570A - Method for welding metal honeycomb carrier - Google Patents

Abstract

PURPOSE:To provide a method for welding a metal honeycomb carrier where the welding of a corrugated plate and a flat plate can rapidly and surely executed. CONSTITUTION:In a method for welding a metal honeycomb carrier where a metallic corrugated plate 33 and a metallic flat plate 35 are laminated, the end surface 37 of a core part 31 which is formed by executing multiple coiling around the corrugated plate and the flat plate is irradiated with the laser beam 43, and the abutting part between the corrugated plate 33 and the flat plate 35 is welde to each other, the laser beam 43 is moved while being vibrated at a constant amplitude in the vertical direction relative to the welding direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for welding a metal honeycomb carrier for welding a metal honeycomb carrier used in a catalytic converter.

[0002]

2. Description of the Related Art Generally, in order to purify exhaust gas, an automobile exhaust system is provided with a metal honeycomb carrier as disclosed in, for example, Japanese Patent Laid-Open No. 54-13462.

FIG. 3 shows the details of this type of metal honeycomb carrier. In this metal honeycomb carrier, metal corrugated plates 11 and flat plates 13 are alternately stacked, and these are centered around a core material. The core portion 17 is formed by multiple winding in a circular shape.

In such a core portion 17, if the corrugated plate 11 and the flat plate 13 are left wound, the core portion 1
After the core portion 17 is formed, a so-called film-out phenomenon occurs in which the corrugated plate 11 and the flat plate 13 located in the central portion of the core portion 17 project in the axial direction of the core portion 17 due to the flow of the exhaust gas into the inside of the core portion 17. The corrugated plate 11 and the flat plate 13 are welded to each other.

FIG. 4 shows an example of a conventional method for welding a metal honeycomb carrier. In this method, the welding head is arranged above the end face 19 with the end face 19 of the core portion 17 facing upward. 21 from the laser beam 23 to the end face 19
And the welding head 21 is moved in the radial direction of the core portion 17, so that the corrugated plate 11 and the flat plate 13 in the portion irradiated with the laser beam 23 are welded at the end face 19.

[0006]

However, in the conventional method for welding a metal honeycomb carrier as described above, when the laser beam 23 is focused on the end surface 19 of the core portion 17 and the welding is performed, the welding is performed at the end surface 19 position. Since the diameter of the laser beam 23 is as small as about 0.2 mm, for example, in order to weld with a width of 2 mm, the welding head 21 needs to be reciprocated 5 times, and it takes a lot of time for welding. There's a problem.

Therefore, the end surface 19 of the core portion 17 is positioned on the welding head 21 side from the focal position of the laser beam 23,
It is conceivable to weld at a position where the diameter of the laser beam 23 is relatively large.
Since there is a large difference in power density between the central portion and the peripheral portion, it is difficult to perform welding at a uniform level.

The present invention has been made to solve the above problems, and it is an object of the present invention to provide a welding method for a metal honeycomb carrier, which enables rapid and reliable mutual welding of a corrugated plate and a flat plate. To aim.

[0009]

According to a first aspect of the present invention, a corrugated plate made of a metal and a flat plate are overlapped with each other, and an end face of a core portion formed by multiple winding of these plates is irradiated with a laser beam, and the corrugated plate is formed. In a method for welding a metal honeycomb carrier, in which a contact portion between a flat plate and a flat plate is welded to each other, the laser beam is moved while vibrating at a constant amplitude in a direction perpendicular to the welding direction.

In the second aspect, the amplitude is 10 mm to 50 mm. Claim 3 has a frequency of 5 Hz to 60 Hz.

[0011]

In the present invention, the laser beam moves while being vibrated with a constant amplitude in the direction perpendicular to the welding direction,
The corrugated plate and the flat plate can be welded to each other.

[0012]

The details of the method of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a welding apparatus for a metal honeycomb carrier for carrying out an embodiment of the method of the present invention. In the figure, reference numeral 31 is a corrugated plate 33 made of metal.
And a flat plate 35 are overlapped with each other, and a core portion formed by multiple winding of these is shown.

The core portion 31 is arranged with the end surface 37 facing upward, and a total reflection mirror (oscillating mirror) 39 is arranged above the end surface 37. A laser beam 43 from a laser oscillator 41 is guided to the total reflection mirror 39 via a condenser lens 45.

Total reflection mirror 39 and condenser lens 45
Is housed in a welding head 47, and inside this welding head 47, a vibrator 49 for oscillating the total reflection mirror 39 in the direction of arrow A in the drawing is arranged.

In the apparatus for welding a metal honeycomb carrier constructed as described above, the laser beam 43 oscillated from the laser oscillator 41 is condensed by the condenser lens 45, guided to the total reflection mirror 39, and then totally reflected. The light is reflected by the reflection mirror 39 and is irradiated on the end surface 37 of the core portion 31.

Further, the welding head 47 has a laser beam 43.
Is oscillated, it is moved at a constant speed in the direction of arrow B in the figure. In this device, however, since the total reflection mirror 39 is vibrated by the vibration exciter 49, the locus of the laser beam 43 irradiated on the end surface 37 of the core portion 31 has a meandering shape as shown in FIG. It becomes a curved line 51.

In this way, the locus of the laser beam 43 is
When the meandering curve 51 is formed, the amplitude end 5 is larger than that in the central portion C.
3, the energy supply amount per unit time becomes extremely large, and the corrugated plate 33 at the portion located at the amplitude end 53
Alternatively, so-called burn-through occurs on the flat plate 35.

When the corrugated plate 33 or the flat plate 35 is thus burned down, the metal honeycomb carrier is clogged and the exhaust resistance of the metal honeycomb carrier is increased.

Therefore, in the present embodiment, the amplitude end 53 of the laser beam 43 on the end face 37 of the core portion 31 and its vicinity are masked by the shielding material 55 which reflects the laser beam 43.

This masking is applied to the end surface 37 of the core portion 31.
Is performed by arranging a pair of shielding materials 55 at a predetermined interval C. When the method of the present invention is carried out, the amplitude D of the laser beam 43 in FIG.
When it is mm to 50 mm, the vibration frequency by the vibration exciter 49 is preferably 5 to 60 Hz, and masking is preferably performed at a distance E of 0.3 mm or more inward from the amplitude end 53.

Therefore, in this embodiment, the laser beam 4
3 is made to move while vibrating at a constant amplitude D in the direction perpendicular to the welding direction.
The diameter of the laser beam 43 in 7 is, for example, 0.2
Even if the diameter is as small as mm, welding can be substantially performed with a width corresponding to the amplitude D of the laser beam 43, and the corrugated plate 33 and the flat plate 35 can be reliably welded.

Further, in this embodiment, the end surface 3 of the core portion 31 is
7, the amplitude end 53 of the laser beam 43 and its vicinity, that is, the portion where the amount of energy supplied per unit time becomes extremely large is masked by the shielding material 55. Therefore, the corrugated plate 33 located at the amplitude end 53 or It is possible to reliably prevent the flat plate 35 from burning through. In the embodiment described above, an example in which the condenser lens 45 is arranged between the laser oscillator 41 and the total reflection mirror 39 has been described, but the direction of the present invention is not limited to this embodiment. It goes without saying that the condenser lens 45 may be arranged between the total reflection mirror 39 and the core portion 31.

Further, in the above-mentioned embodiment, an example in which the condenser lens 45 and the total reflection mirror 39 are separately arranged in the welding head 47 has been described, but the method of the present invention is limited to such embodiment. Instead of this, for example, a so-called R lens in which a condenser lens and a total reflection mirror are integrated may be used and the R lens may be vibrated.

Further, in the above-mentioned embodiments, the case where the masking is performed has been described, but the masking is optional, and it is preferable that the masking can prevent the generation of an overwelded portion and that the welding width be uniform.

[0025]

As described above, according to the present invention, since the laser beam is moved while vibrating in a direction perpendicular to the welding direction with a constant amplitude, unlike the case where the diameter of the laser beam is expanded, the laser beam is expanded. The difference in the power density between the central portion and the peripheral portion of the is reduced, and the welding can be performed at a uniform level as much as possible. As a result, there is an advantage that the corrugated plate and the flat plate can be welded to each other quickly and reliably.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a welding apparatus for a metal honeycomb carrier for carrying out the method of the present invention.

FIG. 2 is an explanatory diagram showing a trajectory of a laser beam.

FIG. 3 is a perspective view showing a state in which a corrugated plate and a flat plate are wound.

FIG. 4 is a perspective view showing a conventional method for welding a metal honeycomb carrier.

[Explanation of symbols]

 31 core part 33 corrugated plate 35 flat plate 37 end face 39 total reflection mirror 43 laser beam

Claims (3)

[Claims] 1. A core part (3) formed by stacking a corrugated plate (33) and a flat plate (35) made of metal and winding them in multiple turns.
Irradiate the laser beam (43) on the end face (37) of 1),
In a method of welding a metal honeycomb carrier, wherein the abutting portions of the corrugated plate (33) and the flat plate (35) are welded to each other, the laser beam (43) is vibrated at a constant amplitude in a direction perpendicular to the welding direction. A method for welding a metal honeycomb carrier, which comprises moving while moving. 2. The method for welding a metal honeycomb carrier according to claim 1, wherein the amplitude is 10 mm to 50 mm. 3. The method for welding a metal honeycomb carrier according to claim 1, wherein the frequency is 5 Hz to 60 Hz.