METHOD FOR DETECTING CENTER COORDINATE OF SPOT WELDING DENT, LASER WELDING METHOD, AND JOINING METHOD

• Main Authors: MATSUO RYUTA, YAMAMOTO TAKESHI, MOTOYOSHI TAKASHI
• Format: Patent
• Language: English; Japanese
• Published: 23.08.2023
• Subjects: CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; SOLDERING OR UNSOLDERING; TRANSPORTING; WELDING; WORKING BY LASER BEAM

To provide a method for detecting a center coordinate of a spot welding dent which can accurately grasp a center coordinate of a spot welding dent.SOLUTION: A method for detecting a center coordinate of a spot welding dent includes: a line laser irradiation step of continuously oscillating output in at least one direction of a direction toward outside from inside of a spot welding dent, and a direction toward the inside from the outside, emitting a laser beam, and thereby irradiating the spot welding dent with a plurality of line lasers linearly forming an irradiation dent; a waveform acquisition step of emitting the laser beam in the line laser irradiation step, and thereby acquiring a waveform of intensity of return light that is light generated from a processing point; an outer edge position coordinate derivation step of deriving position coordinates at a plurality of three or more points on the outer edge of the spot welding dent, from the peak position of the intensity of the waveform of the return light; and a center coordinate calculation step of calculating a center coordinate of the spot welding dent from the position coordinates at the plurality of three or more points on the outer edge derived by the outer edge position coordinate derivation step.SELECTED DRAWING: Figure 4 【課題】スポット溶接打痕の中心座標を正確に把握することができるポット溶接打痕の中心座標の検出方法を提供する。【解決手段】スポット溶接打痕の内側から外側に向かう方向と、外側から内側に向かう方向と、のうちの少なくとも一方向に、連続的に出力を発振してレーザー光を照射することにより、照射痕が線状をなす線レーザーをスポット溶接打痕上に複数照射する線レーザー照射工程と、線レーザー照射工程においてレーザー光を照射することによって加工点から発生する光である戻り光、の強度の波形を取得する波形取得工程と、スポット溶接打痕の外縁上の３つ以上の複数の地点における位置座標を、戻り光の波形の強度のピーク位置から導出する外縁位置座標導出工程と、外縁位置座標導出工程により導出された外縁上の３つ以上の複数の地点における位置座標から、スポット溶接打痕の中心座標を算出する中心座標算出工程と、を備える。【選択図】図４