Abstract: A first resin member including a first contact surface and formed of laser beam-transmissive resin and a second resin member including a second contact surface, which contacts the first contact surface, and formed of laser beam-absorbing resin are arranged one upon the other. A laser welding apparatus includes a clamping unit abutting the second resin member and applying clamping force to the second resin member, a laser emitter emitting laser beam, a laser controller controlling output of the laser beam, a displacement sensor measuring displacement of the second contact surface in stacking direction of the resin members, and a control unit controlling the clamping unit to adjust the clamping force corresponding to displacement amount of the second contact surface continuously or intermittently obtained from the displacement sensor.

Abstract: A first resin member including a first contact surface and formed of laser beam-transmissive resin and a second resin member including a second contact surface, which contacts the first contact surface, and formed of laser beam-absorbing resin are arranged one upon the other. A laser welding apparatus includes a clamping unit abutting the second resin member and applying clamping force to the second resin member, a laser emitter emitting laser beam, a laser controller controlling output of the laser beam, a displacement sensor measuring displacement of the second contact surface in stacking direction of the resin members, and a control unit controlling the clamping unit to adjust the clamping force corresponding to displacement amount of the second contact surface continuously or intermittently obtained from the displacement sensor.