Abstract: The present invention pertains to a brazing method and a brazing apparatus. This brazing method comprises: a brazing material supply step for supplying a brazing material to a to-be-welded part; and a laser irradiation step for irradiating the brazing material having been supplied to the to-be-welded part with a laser beam while moving the laser beam along a brazing direction to form a welding bead. In the laser irradiation step, a gas is injected toward an area to be injected with gas, which is an area encompassing the welding bead located rearward of a laser-irradiated portion of the brazing material in the brazing direction, from above said area or from a front side of said area in the brazing direction.

Abstract: The seam welding apparatus includes a pair of rotating electrodes, an electrode supporting frame, a distance measuring means, and a controller. The electrode supporting frame supports the pair of rotating electrodes. The distance measuring means is provided on the electrode supporting frame and measures a distance to an edge of the steel plate. The controller controls the robot to adjust a running direction of the rotating electrodes so that a deviation comes into zero when a distance actually measured by the distance measuring means deviates from a predetermined distance. Thereby, it is accomplished that the seam welding apparatus is downsized as well as uninfluenced by the surface state and/or shape of workpiece (steel plate).

Abstract: This seam-welding device carries out seam welding while repeating one cycle comprising a melting period, an interruption period, and a heating period implemented either before or after the interruption period. A welding current is applied between a pair of roller electrodes so as to form a welded part between workpieces during the melting period, the application of the current between the roller electrode pair is interrupted so as to solidify the welded part during the interruption period, and a heating current smaller than the welding current is applied between the roller electrode pair so as to heat the laminated body within a solidification temperature range of the welded part during the heating period. Consequently, even when the welding speed is increased, formation of cracks and spatter is effectively suppressed such that a high-quality joined product is obtained.

Abstract: In a seam welding method, a pressing force applied to workpiece by roller electrodes is reduced and an energization to the roller electrodes is stopped when the roller electrodes pass at least a portion where metal sheets are temporarily fastened together through spot welding, and the pressing force to the workpiece by the roller electrodes and the energization to the roller electrodes are restored after the roller electrodes have passed the spot welded portion.

Abstract: Shifts of a reference point C in a robot coordinate system among three postures of a seam welding apparatus 10 are found, and calibration data is obtained (STEP 1). Correction data is found from the calibration data based on deformation of elastic units 22a due to weight of the seam welding apparatus 10 in accordance with the posture of the seam welding apparatus 10 relative to a robot 20 (STEP 5). Teaching data is corrected based on the correction data (STEP 6).

Abstract: A seam welding device sandwiches between a first roller electrode and a second roller electrode a laminate, which is formed by laminating a plurality of workpieces and disposing the thinnest workpiece, which has the smallest thickness among the workpieces, on the outside, to carry out seam welding. The second roller electrode, which is in contact with the thinnest workpiece, is disposed further along the direction of welding progress than the first roller electrode.

Abstract: Distance to the upper face of workpieces W sandwiched between electrode rollers 15 and 16 is measured by a range sensor 41 that has a predetermined positional relationship with the electrode rollers 15 and 16 (STEPs 1, 3). Correction is made based on the distance found by the range sensor 41 by moving the pair of electrode rollers 15, 16 with reference to the workpieces W so that an angle Rx between a straight line L0 connecting centers of the pair of electrode rollers 15, 16 and the surface of the plurality of workpieces W is preset angle (STEP 5).

Abstract: This seam-welding device carries out seam welding while repeating one cycle comprising a melting period, an interruption period, and a heating period implemented either before or after the interruption period. A welding current is applied between a pair of roller electrodes so as to form a welded part between workpieces during the melting period, the application of the current between the roller electrode pair is interrupted so as to solidify the welded part during the interruption period, and a heating current smaller than the welding current is applied between the roller electrode pair so as to heat the laminated body within a solidification temperature range of the welded part during the heating period. Consequently, even when the welding speed is increased, formation of cracks and spatter is effectively suppressed such that a high-quality joined product is obtained.

Abstract: A seam welding device sandwiches between a first roller electrode and a second roller electrode a laminate, which is formed by laminating a plurality of workpieces and disposing the thinnest workpiece, which has the smallest thickness among the workpieces, on the outside, to carry out seam welding. The second roller electrode, which is in contact with the thinnest workpiece, is disposed further along the direction of welding progress than the first roller electrode.

Abstract: In a seam welding method, a pressing force applied to workpiece by roller electrodes is reduced and an energization to the roller electrodes is stopped when the roller electrodes pass at least a portion where metal sheets are temporarily fastened together through spot welding, and the pressing force to the workpiece by the roller electrodes and the energization to the roller electrodes are restored after the roller electrodes have passed the spot welded portion.

Abstract: Shifts of a reference point C in a robot coordinate system among three postures of a seam welding apparatus 10 are found, and calibration data is obtained (STEP 1). Correction data is found from the calibration data based on deformation of elastic units 22a due to weight of the seam welding apparatus 10 in accordance with the posture of the seam welding apparatus 10 relative to a robot 20 (STEP 5). Teaching data is corrected based on the correction data (STEP 6).

Abstract: It is an object of the present invention to provide a seam welding warpage prevention method and apparatus capable of preventing warpage caused by cooling contraction after welding, in a case where workpieces are different from one another in material and thickness, and thus not uniform in thermal contraction. In the seam welding warpage prevention method for welding a plurality of workpieces W1 and W2 that are not uniform in thermal contraction with respect to an energizing direction, the workpieces W1 and W2 are clamped with a pair of roller electrodes 23 and 33 while applying current. The welding is performed in a state where the roller electrode 33 that abuts on the workpiece W2 having higher thermal contraction is offset in an advancing direction ahead of the roller electrode 23 that abuts on the workpiece W1 having lower thermal contraction.

Abstract: Distance to the upper face of workpieces W sandwiched between electrode rollers 15 and 16 is measured by a range sensor 41 that has a predetermined positional relationship with the electrode rollers 15 and 16 (STEPs 1, 3). Correction is made based on the distance found by the range sensor 41 by moving the pair of electrode rollers 15, 16 with reference to the workpieces W so that an angle Rx between a straight line L0 connecting centers of the pair of electrode rollers 15, 16 and the surface of the plurality of workpieces W is preset angle (STEP 5).

Abstract: The seam welding apparatus includes a pair of rotating electrodes, an electrode supporting frame, a distance measuring means, and a controller. The electrode supporting frame supports the pair of rotating electrodes. The distance measuring means is provided on the electrode supporting frame and measures a distance to an edge of the steel plate. The controller controls the robot to adjust a running direction of the rotating electrodes so that a deviation comes into zero when a distance actually measured by the distance measuring means deviates from a predetermined distance. Thereby, it is accomplished that the seam welding apparatus is downsized as well as uninfluenced by the surface state and/or shape of workpiece (steel plate).

Abstract: It is an object of the present invention to provide a seam welding warpage prevention method and apparatus capable of preventing warpage caused by cooling contraction after welding, in a case where workpieces are different from one another in material and thickness, and thus not uniform in thermal contraction. In the seam welding warpage prevention method for welding a plurality of workpieces W1 and W2 that are not uniform in thermal contraction with respect to an energizing direction, the workpieces W1 and W2 are clamped with a pair of roller electrodes 23 and 33 while applying current. The welding is performed in a state where the roller electrode 33 that abuts on the workpiece W2 having higher thermal contraction is offset in an advancing direction ahead of the roller electrode 23 that abuts on the workpiece W1 having lower thermal contraction.

Abstract: Disclosed are a bonded product, and a manufacturing method and manufacturing device therefor. To obtain a bonded product formed of a solidified material of a molten metal which has been poured into a forming mold with a workpiece, all or part of which is already held therein, or formed of a semi-solidified slurry which is contained in the forming mold together with the workpiece, the semi-solidified slurry or the molten metal is relatively made to flow on the end faces of the workpiece while friction sufficient to break the passive state existing at the surface of the molten metal or the semi-solidified slurry is generated between the workpiece and the semi-solidified slurry or the molten metal.

Abstract: A seam welding machine includes a first roller electrode and a second roller electrode that hold a layered body formed by layering a plurality of workpieces. The first roller electrode is in contact with a thinnest workpiece, which is disposed on an outermost side of the layered body. The seam welding machine has a current-branching electrode held in contact with the thinnest workpiece, and which is charged with a polarity opposite to that of the first roller electrode. Accordingly, when an electric current is applied between the first roller electrode and the second roller electrode that hold the layered body, a branch electric current is applied from the first roller electrode to the current-branching electrode, or a branch electric current is applied from the current-branching electrode to the first roller electrode.

Abstract: A resistance welding method, which resistance-welds a pair of workpieces by gripping the workpieces with a pair of electrode tips under a prescribed welding pressure, and supplies a welding current through the electrode tips to the workpieces, includes the steps of detecting a change in an amount of expansion of a nugget produced in the workpieces, along a direction in which the electrode tips grip the workpieces therebetween, determining whether the detected change is smaller than a threshold value or not, and gradually increasing the welding current flowing through the workpieces after the detected change is judged as being smaller than the threshold value.

Abstract: A method for joining dissimilar materials by superposing, one over the other, a first material and a second material having a larger intrinsic resistance than that of the first material, heating the second material and pressing the first material and the second material against each other, which comprises conducting induction heating only from the side of the first material upon heating the second material to thereby heat the second material at the portions in contact with the first material.

Abstract: The purpose of the present invention is to change hollow resonance frequency in a cabin without changing the dimensions of the cabin and not providing any partition in the cabin. The present invention provides noise proof structure of a cabin reducing furry noise so as to improve livability and comfortability for an operator. A resonator resonating at frequency of hollow resonance is provided at a position at which sound pressure is high when the hollow resonance occurs. A rotary sensor measuring rotary speed of an engine of the working machine or the like having the cabin, an actuator opening and closing a partition at the opening, and a controller controlling the partition through the actuator corresponding to the rotary speed measured by the rotary sensor are provided.