Patent ID: 8728268
Filing Date: 2014-05-20
Classification: B29C,B29K,B29L

Abstract:
1. A method for manufacturing a resin molding, the resin molding including a light-absorbing resin member having a three-dimensional weld region extending in a predetermined extending direction and a light-transmitting resin member having a corresponding three-dimensional weld region extending in the predetermined extending direction, the method comprising: arranging and pressing the three-dimensional weld region of the light-absorbing resin member and the corresponding three-dimensional weld region of the light-transmitting resin member so that they are opposed to each other and are brought into contact with each other, the three-dimensional weld region including a maximum height portion; setting a plurality of irradiation areas with at least part of a loop shape in the extending direction of the three-dimensional weld regions and arranging a plurality of laser irradiation scanning heads corresponding to the respective irradiation areas and above respective centers of the loop shapes of the irradiation areas so that the scanning heads each have a center irradiation direction inclined to face the corresponding loop shape and the maximum height portion of the weld region is disposed in between the irradiation areas of the scanning head, and that the scanning heads are configured to emit laser beams that are incident on the light-transmitting resin member, with the irradiation areas including a single irradiation area upon which a corresponding scanning head can irradiate with a laser beam and a composite irradiation area which adjacent scanning heads can irradiate with respective laser beams, each of the laser irradiation scanning heads including a laser optical system with a Galvano scanner so as to perform three-dimensional scanning for laser beam welding; activating the plurality of scanning heads to cause the plurality of laser beams to repeatedly scan the single irradiation area along a first trajectory in the extending direction of the single irradiation area and part of both the single irradiation area and the composite irradiation area along a second trajectory in the extending direction in such a manner that the respective laser beams are irradiated alternately within the composite irradiation area while the laser beams are scanned along the first trajectory and the second trajectory alternately, so that the weld regions in their entirety are repeatedly heated to stepwisely increase the temperature thereof and fused to weld the light-transmitting resin member and the light-absorbing resin member.