| 摘要 |
PURPOSE:To produce a scroll in a high precision and a low cost by fitting several convex parts provided on the bottom of a lap into penetrated holes on a mirror board and welding them from the other side of the penetrated holes. CONSTITUTION:A lap 10b is combined with a mirror board 10a by inserting a projection 11 of the lap 10b into a penetrated hole 12. Then, from under the penetrated hole 12 on the mirror board 10a, a frictional welding rod machine 13 in rotation is inserted for giving frictional welding to the projection 11 and a part of the penetrated hole 12. In this construction, the projection 11 of the lap 10b is welded including a part of the mirror board 10b for producing a scroll in a high precision and a low cost. |
