JP5050261B2 - Laser welding method - Google Patents

Description

  The present invention relates to a laser welding method and a railway vehicle structure.

Conventionally, a method described in Patent Document 1 is known as a method of laser welding plate members together. In the method described in Patent Document 1, one main surface of the first plate member and one main surface of the second plate member are overlapped, and laser light is irradiated from the other main surface side of the second plate member. Thus, the first and second plate materials are heated and melted and joined.
Japanese Patent Laid-Open No. 2001-164031

  However, in the conventional method, a welded portion formed by laser light irradiation may penetrate the first plate material. In this case, since the welded portion is exposed on the other main surface of the first plate member, there has been a problem that the welding marks are conspicuous. On the other hand, even if the welded portion is non-penetrating with respect to the first plate material, the first plate material is deformed by the thermal contraction of the welded portion, and this deformation causes distortion on the other main surface of the first plate material. There was a case. Since the distortion appears at a position corresponding to the welded portion, there has been a problem that the welding mark is conspicuous on the other main surface of the first plate member even though the welded portion does not penetrate.

  Therefore, an object of the present invention is to provide a laser welding method and a railway vehicle structure capable of making a welding mark inconspicuous on a surface not irradiated with laser light.

  In the laser welding method of the present invention, the second member is disposed on one main surface of the plate-shaped first member, and the first member is irradiated with laser light from the one main surface side of the first member. A laser welding method for welding a second member, comprising a roughening step of roughening the other main surface of the first member, wherein the other main surface of the roughened first member is It is characterized by not being painted.

  In the laser welding method of the present invention, the other main surface of the first member is roughened. Due to the roughening, random irregularities are formed on the other main surface of the first member. Since this random unevenness | corrugation scatters light, even when a welding trace has adhered to the other main surface of the 1st member, the visibility of a welding trace can be reduced. In addition, since the other main surface of the roughened first member is not coated, the unevenness difference is not filled by the coating and the other main surface of the first member is not flattened. Therefore, it is possible to maintain the effect of reducing the visibility of the weld mark due to the unevenness. Therefore, if the laser welding method of the present invention is used, welding marks can be made inconspicuous on the other main surface of the first member, that is, the surface not irradiated with laser light.

  In the laser welding method of the present invention, the second member is disposed on one main surface of the plate-shaped first member, and the first member is irradiated with laser light from the one main surface side of the first member. A laser welding method for welding a second member to a roughening step of roughening the other main surface of the first member, and after the roughening step, to the other main surface of the first member And a coating process for coating, wherein the coating process forms a coating film that follows the irregularities formed on the other main surface of the first member by the roughening process.

  In the laser welding method of the present invention, the other main surface of the first member is roughened. Since the random unevenness caused by the roughening scatters light, the visibility of the welding trace can be reduced even when a welding trace is generated on the other main surface of the first member. The laser welding method of the present invention has a painting process, but in this painting process, a coating film that follows random irregularities is formed, so that the other main surface of the first member is flattened by painting. There is nothing. Therefore, light can be scattered by unevenness even after painting. Therefore, if the laser welding method of the present invention is used, welding marks can be made inconspicuous on the other main surface of the first member, that is, the surface not irradiated with laser light.

  In the present invention, it is preferable that the first member and the second member are spot-welded at a plurality of locations by laser light irradiation. In the case of spot welding, unlike the case of continuous welding, welds are scattered. Therefore, welding marks are also scattered on the other main surface of the first member. As a result, the welding marks can be made less noticeable.

  In the laser welding method of this invention, it is preferable that the welding part formed in the 1st member and the 2nd member by irradiation of the laser beam is non-penetrating with respect to the 1st member. In this case, the welded portion is not exposed on the other main surface of the first member, and only distortion appears. Therefore, compared with the case where the welding part is exposed, a welding trace becomes inconspicuous.

  In the laser welding method of the present invention, it is preferable that the roughening step is performed after welding the first member and the second member. In this case, since the roughening is performed after the weld mark is formed, random irregularities can be formed on the weld mark. Therefore, it is possible to make the welding marks less noticeable.

  In the laser welding method of the present invention, it is preferable that the other main surface of the first member is a matte surface in the roughening step. By making the other main surface of the first member a satin surface, it is possible to scatter light moderately, and to make it more difficult to make a shadow on the portion of the welding trace.

In the laser welding method of the present invention, in the roughening step, it is preferable that the other main surface of the first member is roughened by performing shot blasting. By performing shot blasting, random irregularities can be reliably formed on the other main surface of the first member. Further, by performing the shot blasting process, the other main surface of the first member is cured and a high residual compressive stress is applied. Therefore, the strength of the first member can be improved.

  In the laser welding method of the present invention, the first member is preferably made of stainless steel. Since stainless steel is more easily peeled off than iron or aluminum, it is difficult to use the technique of making the welding marks inconspicuous by applying a thick paint. The laser welding method of the present invention makes the trace of welding inconspicuous by roughening, so it is very useful for members made of stainless steel.

  The railway vehicle structure of the present invention is a railway vehicle structure provided with a skin panel, and the skin panel includes one main surface located inside the vehicle and the other principal surface located outside the vehicle. It has an outer plate and a reinforcing member laser welded to one main surface of the outer plate, and the other main surface of the outer plate is a rough surface.

  In the railway vehicle structure of the present invention, the other main surface of the outer plate is a rough surface, and random irregularities are formed. Since the random unevenness scatters light, the visibility of the weld mark is lowered. Therefore, according to the railway vehicle structure of the present invention, welding marks can be made inconspicuous on the outside of the vehicle.

  In the railway vehicle structure of the present invention, the outer plate and the reinforcing member are preferably spot welded at a plurality of locations. In the case of spot welding, unlike the case of continuous welding, the welded portions and the welding marks are scattered. Therefore, the welding mark can be made less noticeable.

  In the railway vehicle structure of the present invention, the welded portion formed on the outer plate and the reinforcing member by laser welding is preferably non-penetrating with respect to the outer plate. In this case, only the distortion appears on the other main surface of the outer plate without exposing the welded portion. Therefore, it becomes easy to make the welding mark inconspicuous as compared with the case where the welded portion is exposed.

  In the railway vehicle structure of the present invention, it is preferable that the other main surface of the outer plate is a pear ground. By making the other main surface of the outer plate a satin surface, it is possible to scatter light moderately and to make it more difficult to make a shadow on the portion of the welding mark.

  In the railway vehicle structure of the present invention, the outer plate is preferably made of stainless steel. The outer plate made of stainless steel is more easily peeled off than the one made of iron or aluminum. Therefore, it is difficult to use the technique of making the welding mark inconspicuous by applying a thick coating. In the railway vehicle structure according to the present invention, the other main surface of the outer plate is roughened, thereby reducing the visibility of the weld mark. Therefore, welding marks can be made inconspicuous even if the paint is not applied thickly.

  ADVANTAGE OF THE INVENTION According to this invention, the laser welding method and railroad vehicle structure which can make a welding trace inconspicuous in the surface which is not irradiating a laser beam can be provided.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description, the same reference numerals are used for the same elements or elements having the same function, and redundant description is omitted.

  FIG. 1 is a perspective view showing a railway vehicle structure according to the present embodiment. FIG. 2 is a side view of a waist panel provided in the railway vehicle structure according to the present embodiment, and FIGS. 3 and 4 are views showing a manufacturing process of the waist panel.

  As shown in FIG. 1, the railway vehicle structure 1 constitutes a floor structure 2 constituting a floor part, a roof structure 3 constituting a roof part, a side structure 4 constituting a side part, and a front part and a rear part. The wife structure 5 is joined to each other.

  The side structure 4 is located above the four door units 9 and the upper edge of the door unit 9, the door upper panel 10 joined to the roof structure 3, between the door units 9 and 9, and at the front and rear ends. It has five side structure blocks 11 to be arranged. The side structure block 11 includes a curtain panel 12, a window unit 13, a pair of blowing panels 14, and a waist panel (outer panel) 16.

  The curtain panel 12 is a panel that is positioned above the upper edge of the window unit 13 and is joined to the roof structure 3. The blowing panel 14 is a panel located between the door unit 9 and the window unit 13 and between the wife structure 5 and the window unit 13. The waist panel 16 is a panel positioned below the lower edge of the window unit 13 and joined to the floor structure 2.

  The waist panel 16 will be described. As shown in FIG. 2, the waist panel 16 has an outer plate (first member) 18, four corrugated plates (second member, reinforcing members) 20, and is located on both sides and the center and extends in the vertical direction. The support post 22, the cross beam member 24 extending horizontally at the upper end, and the joining member 26 extending horizontally at the lower end.

  As shown in FIG. 3, the outer plate 18 has a substantially flat plate shape and is made of stainless steel. One main surface 18a of the outer plate 18 is a surface located inside the vehicle, and the other main surface 18b of the outer plate 18 is a surface located outside the vehicle. As shown in FIG. 2A, the other main surface 18 b of the outer plate 18 has a satin-like unevenness.

  The corrugated plate 20 is a corrugated plate formed so that the inner top portion 28 located inside the vehicle and the outer top portion 30 located outside the vehicle appear alternately and continuously. The corrugated plate 20 is made of stainless steel.

  When the waist panel 16 is manufactured, the outer plate 18 and the corrugated plate 20 are first welded. Next, the support 22 is welded to the welded outer plate 18 and corrugated plate 20. And the cross beam member 24 and the joining member 26 are welded to what welded the support | pillar 22, the outer plate | board 18, and the corrugated plate 20. FIG. The waist panel 16 is manufactured through the above steps.

  Here, a welding method of the outer plate 18 and the corrugated plate 20 will be described. First, the outer plate 18 and the corrugated plate 20 are prepared. The outer plate 18 is prepared so that the other main surface 18b is not pear ground. As shown in FIG. 3A, the prepared corrugated plate 20 is disposed on one main surface 18 a of the outer plate 18, and the corrugated plate 20 and the outer plate 18 are overlapped. At this time, the outer top 30 of the corrugated plate 20 is made to face one main surface 18 a of the outer plate 18.

  After superposing the outer plate 18 and the corrugated plate 20, as shown in FIG. 3 (b), using the laser welding device 32 that emits the laser light L, the outer plate is started from one main surface 18 a side of the outer plate 18. 18 and corrugated plate 20 are irradiated with laser light L. The laser light L is emitted from the top of the corrugated plate 20 toward the outer apex 30 of the corrugated plate 20. Further, the laser beam L is irradiated intermittently along the direction in which the outer apex 30 extends. Thereby, the corrugated plate 20 and the outer plate 18 are spot-welded at a plurality of locations. The welded portion LP formed by the irradiation with the laser beam L is non-penetrating with respect to the outer plate 18.

  When the other main surface 18b of the outer plate 18 is viewed after spot welding, a plurality of distortions SP are generated as shown in FIG. The distortion SP is due to thermal contraction of the welded portion, and is generated at a position corresponding to the welded portion. The other main surface 18b of the outer plate 18 in which such strain SP is generated is roughened (roughening step). More specifically, the other main surface 18b of the outer plate 18 is subjected to shot blasting for hitting the granular material. As a result, as shown in FIG. 4B, random irregularities are formed on the other main surface 18 b of the outer plate 18. By forming random irregularities, the other main surface 18b of the outer plate 18 has a matte shape. It should be noted that the other main surface 18b of the outer plate 18 having a satin finish is not coated.

  As described above, in the waist panel 16, the other main surface 18b of the outer plate 18 is roughened, thereby forming random irregularities on the surface 18b. Since the formed random unevenness scatters light, the visibility of the strain SP decreases. Since the other main surface 18b that has been roughened is not coated, the unevenness difference is not filled with the coating and the surface is not flat. Therefore, in the waist panel 16 in which the other main surface 18b is a surface located outside the vehicle, light is scattered by the unevenness, and the distortion SP is difficult to distinguish. Therefore, the distortion SP, that is, the welding mark can be made inconspicuous on the outside of the vehicle.

  In the waist panel 16, the outer plate 18 and the corrugated plate 20 are spot-welded at a plurality of locations. In the case of spot welding, unlike the case of continuous welding, welds are scattered. Therefore, the strain SP is also scattered on the other main surface 18 b of the outer plate 18. As a result, the distortion SP can be made less noticeable.

  In the waist panel 16, the welded portion LP formed by the irradiation with the laser beam L is non-penetrating with respect to the outer plate 18. In this case, the welded portion LP is not exposed on the other main surface 18b of the outer plate 18, and only the distortion SP appears. Therefore, compared with the case where welding part LP is exposed, a welding trace becomes inconspicuous.

  In the waist panel 16, after welding the outer plate 18 and the corrugated plate 20, the other main surface 18b of the outer plate 18 is roughened. In this case, since roughening is performed after the distortion SP occurs, random irregularities can be formed on the distortion SP. Therefore, the distortion SP can be made less noticeable.

  In the waist panel 16, the other main surface 18b of the outer plate 18 is roughened by performing shot blasting. By performing shot blasting, random unevenness can be reliably formed on the other main surface 18b of the outer plate 18. Further, by performing the shot blasting process, the other main surface 18b of the outer plate 18 is cured and a high residual compressive stress is applied. Therefore, the strength of the outer panel 18 and the waist panel 16 can be improved.

  In the waist panel 16, the other main surface 18b of the outer plate 18 is a pear ground. By making the other main surface 18b of the outer plate 18 a satin surface, it is possible to scatter light moderately and to make it more difficult to make a shadow on the portion of the distortion SP.

  In the waist panel 16, the outer plate 18 is made of stainless steel. Stainless steel is more easily peeled off than iron or aluminum, and it is difficult to use a technique that makes welding marks inconspicuous by applying a thick coating. Therefore, in the outer plate 18 made of stainless steel, the above-described method for making the welding marks inconspicuous through a roughening step is very useful.

  The present invention is not limited to the above-described embodiment, and various modifications can be made.

  In the present embodiment, the method of welding the outer plate 18 and the corrugated plate 20 at the time of manufacturing the waist panel 16 has been described, but the door upper panel 10, the curtain panel 12, and the blowing panel 14 shown in FIG. In the case where the outer plate and the corrugated plate are included in the same manner as described above, the above-described welding method can be applied to the manufacture of these panels 10, 12, and 14.

  In the present embodiment, the outer plate 18 and the corrugated plate 20 are spot welded at a plurality of locations, but the outer plate 18 and the corrugated plate 20 may be continuously welded. In addition, although the welded portion LP is not penetrating the outer plate 18, the welded portion LP may penetrate the outer plate 18. In addition, after the outer plate 18 and the corrugated plate 20 are welded, the other main surface 18b of the outer plate 18 is roughened. However, the outer plate 18 is roughened in advance, and the roughened outer surface 18b. The plate 18 and the corrugated plate 20 may be welded. However, from the viewpoint of making the welding marks less conspicuous, it is preferable to use this embodiment.

  In the present embodiment, the other main surface 18b of the outer plate 18 is roughened by performing shot blasting. However, the method of roughening is not limited to shot blasting. In the present embodiment, the outer plate 18 is made of stainless steel, but the material constituting the outer plate 18 is not limited to this.

  In the present embodiment, the other main surface 18b of the roughened outer plate 18 is not coated, but may be painted. However, the coating film formed by painting must follow the unevenness formed on the other main surface 18b of the outer plate 18 by roughening. In this case, it is possible to avoid that the unevenness difference is filled by painting and the other main surface 18b is flattened, so that the visibility of the welding trace is reduced by the scattered light generated by the unevenness even after painting. The effect can be kept.

It is a perspective view which shows the railway vehicle structure which concerns on this embodiment. It is a side view of the waist panel with which the railroad vehicle structure concerning this embodiment is provided. It is a figure which shows the manufacturing process of the waist panel with which the rail vehicle structure which concerns on this embodiment is provided. It is a figure which shows the manufacturing process of the waist panel with which the rail vehicle structure which concerns on this embodiment is provided.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Railway vehicle structure, 16 ... Waist panel (outer panel), 18 ... Outer plate (first member), 18a ... One main surface, 18b ... Other main surface, 20 ... Corrugated plate (second member, reinforcement) Members), 28 ... inner apex, 30 ... outer apex, 32 ... laser welding apparatus, L ... laser beam, LP ... weld, SP ... distortion.

Claims (5)

The second member is disposed on one main surface of the first member having a plate shape, and the first member and the second member are irradiated by irradiating laser light from the one main surface side of the first member. A laser welding method for welding,
The first member and the second member are spot welded at a plurality of locations by irradiation with the laser beam,
After welding the first member and the second member, the other main surface of the first member is roughened to form random irregularities on the main surface, and the other main surface of the first member is a roughening step of the satin finished surface, the laser welding method characterized by not subjected to paint on the other main surface of the first member and the roughened. The second member is disposed on one main surface of the first member having a plate shape, and the first member and the second member are irradiated by irradiating laser light from the one main surface side of the first member. A laser welding method for welding,
The first member and the second member are spot welded at a plurality of locations by irradiation with the laser beam,
After welding the first member and the second member, the other main surface of the first member is roughened to form random irregularities on the main surface, and the other main surface of the first member is A roughening process with pear ground ;
After the roughening step, a coating step of coating the other main surface of the first member,
Wherein in the coating step, the laser welding method characterized by forming a coating film to follow the said unevenness formed on the other main surface of the first member by roughening process. 3. The laser welding method according to claim 1, wherein a weld portion formed on the first member and the second member by irradiation of the laser light is non-penetrating with respect to the first member. Wherein the roughening step, the laser welding method of any one of claims 1-3, characterized in that roughening the other main surface of the first member by performing shot blast treatment. The laser welding method according to any one of claims 1 to 4 , wherein the first member is made of stainless steel.

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