Abstract: To provide a seam welding apparatus and a seam welding method that may operate at a low pressure to obtain a suitable overlapped alignment amount. In the seam welding apparatus, a trailing plate clamp moving means is provided with link mechanisms for overlapping and aligning a leading end of a trailing plate with a trailing end of a leading plate and a link drive source for operating the link mechanisms under an extended condition. The link mechanisms are arranged in parallel along both side edges of the trailing plate. The pair of link mechanisms are connected to a link drive source to form a parallel link mechanism assembled through a coupling link. Also, a movable portion of the leading plate clamp means has a tilt pivot. This tilt pivot is adapted to be movable so that the overlapped alignment amount may be adjusted.

Abstract: To provide a seam welding apparatus and a seam welding method that may operate at a low pressure to obtain a suitable overlapped alignment amount. In the seam welding apparatus, a trailing plate clamp moving means is provided with link mechanisms for overlapping and aligning a leading end of a trailing plate with a trailing end of a leading plate and a link drive source for operating the link mechanisms under an extended condition. The link mechanisms are arranged in parallel along both side edges of the trailing plate. The pair of link mechanisms are connected to a link drive source to form a parallel link mechanism assembled through a coupling link. Also, a movable portion of the leading plate clamp means has a tilt pivot. This tilt pivot is adapted to be movable so that the overlapped alignment amount may be adjusted.

Abstract: To provide a cutting apparatus for a welding machine, which is less costly, at least one of each of upper blade portion ascending/descending guide units, a lower blade portion ascending/descending guide unit and an ascending/descending guide unit for holding a clearance between the upper and lower blade portions is used in common as a co-use ascending/descending unit out of the plurality of ascending/descending guide units. Also, there is provided a hydraulic drive unit normally depending upon the operation of the upper blade portion ascending/descending link unit and working as a drive source for the upper blade portion ascending/descending link unit when necessary, in conjunction with the upper blade portion or the upper blade portion ascending/descending link unit.

Abstract: An object of the present invention is to provide plate width center alignment method and apparatus for a welding machine, which can dispense with a detection driving device, which is simple in construction but can perform the detection from a position closest to a cutting-welding position, and which is high in plate width center alignment accuracy. Plate side edge detectors which are included in a plate width center alignment means for detecting plate widths of two cut plates and aligning plate width centers with each other, and which detect widthwise plate side edges of the two cut plates, are disposed on a movable frame provided with a cutting means and a welding means, elongated in the width direction of a web and movable in that direction.

Abstract: A metal strip connecting method for welding the tail end of a preceding metal strip and the forward end of a succeeding metal strip. The tail and forward end portions of the two strips which are clamped by respective clampers are cut to required sizes by cutting means which are respectively mounted on frames secured to tables provided with the clampers and which are movable along a passage extending in the lateral direction of the strips. The cut end faces are butted against each other and welded selectively by flash welding or laser beam welding in accordance with the material of the strips. The flash welding is effected by supplying a flash current between the clampers, and the laser beam welding is effected by means of a laser beam machining head which is mounted on the frame secured to either one of the tables and which is movable along said passage.