Abstract: A rolled steel plate 1 wound in a roll shape is unrolled and is cut in given dimensions to form a blank 2. In this case, a cut surface 2a is caused to incline at 1 to 3 degrees relative to the thickness direction of the blank 2, wherein the inclination direction of the cut surfaces 2a, 2a on each side is reversed. The blank 2 cut in this manner is roll-formed to cause the cut surfaces 2a, 2a to confront each other. Since the cut surfaces 2a, 2a on each side incline at 1 to 3 degrees in the opposite direction as described above, the cut surfaces 2a, 2a are caused to be parallel. Then, the confronting sections are laser-welded to form a cylindrical body 3.

Abstract: A rolled steel plate 1 wound in a roll shape is unrolled and is cut in given dimensions to form a blank 2. In this case, a cut surface 2a is caused to incline at 1 to 3 degrees relative to the thickness direction of the blank 2, wherein the inclination direction of the cut surfaces 2a, 2a on each side is reversed. The blank 2 cut in this manner is roll-formed to cause the cut surfaces 2a, 2a to confront each other. Since the cut surfaces 2a, 2a on each side incline at 1 to 3 degrees in the opposite direction as described above, the cut surfaces 2a, 2a are caused to be parallel. Then, the confronting sections are laser-welded to form a cylindrical body 3.

Abstract: The invention relates to a laser beam welding method for carbon steels applied to laser beam welding of carbon steels of different carbon content, and in order to improve uniformity of fused metal in the welded region, a laser beam is applied obliquely to the joint region between the carbon steels from the side of the carbon steel having the lower carbon content. When manufacturing a vehicle wheel 1 by this method, the laser beam is applied obliquely from the side of the hub 3 of rolled steel plate which contains about 0.1% of carbon to the joint region with the boss 2 of carbon steel for machine structural use which contains about 2% of carbon so as to fuse the end of the hub 3 and cause it to penetrate into the welded region.

Abstract: Upper and lower shell members of aluminum-plated steel panels have respective flanges overlapping each other and welded to each other by a laser beam, thereby forming a fuel tank. One of the flanges has a stepped region spaced from the other of the flanges, thereby defining a gap between the stepped region and the other flange. The laser beam is applied to the flanges closely to the gap for discharging unwanted components such as aluminum from a welded area of the flanges into the gap. Therefore, the amount of aluminum contained in the welded area is reduced to increase the bonding strength of the welded area.

Abstract: An exhaust muffler comprising an outer cylindrical body, front and rear end plates mounted on each end of the outer cylindrical body, porous plates fitted on the insides of the outer cylindrical body and each of the end plates, and partition plates for dividing the internal space of the outer cylindrical body into several chambers, wherein when joining the component parts with each other, three or four component parts are superposed via their joint portions each on the other and integrally joined by laser beam welding so as to obtain a reduction of welding steps and minimize the thermal influence in the manufacturing process while ensuring an air-tight condition of the partitioned chambers. When an exhaust pipe and tail pipe are connected to the end plates, respectively, they are laser beam welded to the end plates in a superposed fashion.

Abstract: Upper and lower shell members of aluminum-plated steel panels have respective flanges overlapping each other and welded to each other by a laser beam, forming a fuel tank. One of the flanges has a stepped region spaced from the other of the flanges, defining a gap between the stepped region and the other flange. The laser beam is applied to the flanges closely to the gap for discharging unwanted components such as aluminum from a welded area of the flanges into the gap. Therefore, the amount of aluminum contained in the welded area is reduced to increase the bonding strength of the welded area.

Abstract: A supply line for supplying a sealant from a sealant supply source to a sealing robot has pressure sensors and is coupled to relief valves through branch lines. If the pressure in the supply line excessively rises or drops, then the relief valves are opened to release the pressure from the supply line and the supply pump is inactivated. The pipes, devices, and pump on the supply line are therefore protected from damage. The sealing robot has an sealant applicator gun movable with respect to an article to which the sealant is to be applied by the sealing robot. A pump driving device is controlled to vary the rate at which the sealant is discharged from the pump as a function of the speed of relative movement of the sealant applicator gun with respect to the article.