Patent ID: 9517529
Filing Date: 2016-12-13
CPC Classification: B23K

Claim Text:
1. A friction stir welding system for welding at least two parts to be assembled, the friction stir welding system comprising: a welding unit which includes a welding device which includes at least one welding head provided with a rotating pin; a counter-bearing unit which offers a support surface designed to support the parts to be assembled against a pressure exerted by each of the at least one welding head; wherein: the at least one welding head is moved relative to the support surface of the counter-bearing unit, in a first direction parallel to an axis of rotation of the rotating pin of each of the at least one welding head; each of the at least one welding head is moved in a second direction which is orthogonal to the axis of rotation of the rotating pin of the at least one welding head; the counter-bearing unit is configured for moving the support surface along the second direction; wherein the counter-bearing unit includes two clamp rollers set apart from each other and which have a common axis of revolution which is substantially orthogonal to the first direction and orthogonal to the second direction, where each of the clamp rollers has a main circumferential track which forms at least one part of the support surface; and wherein the counter-bearing unit is configured for moving the clamp rollers towards each other so that two respective side-walls of each of the clamp rollers are configured to contact and sandwich a portion of a first part of the at least two parts between the two respective side-walls, and the side-wall of each clamp roller is connected to the corresponding main circumferential track by a curved circumferential part.