Patent ID: 9604306
Date: 2017-03-28
CPC Classifications: B23K

Claim:
1. A friction-stir welding tool, comprising: a front side shoulder extending in an axis direction; a rear side shoulder which is provided to axially oppose the front side shoulder, and comes into contact with plate materials to interpose an abutment portion of the plate materials between the front side shoulder and the rear side shoulder; and a probe which is disposed to penetrate the plate materials between the front side shoulder and the rear side shoulder, extends in the axis direction, and connects the front side shoulder and the rear side shoulder to each other, wherein the probe includes a first screw part provided on at least one end section in the axis direction and a stirring groove which is provided to a portion of the probe in which the first screw part is not provided, wherein at least one of the front side shoulder and the rear side shoulder includes a second screw part which is provided in a hole part formed in the axis direction from an end surface of the at least one of the front side shoulder and the rear side shoulder, the second screw part is in threaded engagement with the first screw part, and a state of the threaded engagement is changed so that the front side shoulder and the rear side shoulder axially move closer to each other as the front side shoulder and the rear side shoulder rotate relative to each other, and the second screw part links at least one of the front side shoulder and the rear side shoulder with the probe due to the threaded engagement between the first screw part and the second screw part, wherein lead angles of the first screw part and the second screw part are set such that a state where a screwing force when the state of the threaded engagement is changed and the second screw part is screwed into the first screw part and a reaction force of a welding pressure of the rear side shoulder receiving from the plate material are balanced with each other becomes a state where the welding pressure of the rear side shoulder with respect to the plate material is suitable during the welding, and wherein a diameter-expanding hole part having a larger constant inner diameter than an outer diameter of the stirring groove of the probe is formed between the second screw part and the end surface in the hole part.