METHOD AND ROLLER SEAM TYPE RESISTANCE WELDER FOR ROLLER SEAM WELDING OF SEAM OF OVERLAPPING THIN PLATES

摘要

PURPOSE: To reduce electrical resistance variation of sheets to the extent of generating no problem and to reduce mechanical vibrations thereof, too, by decreasing welding force at the time of starting welding. CONSTITUTION: In a welding force control device which is disposed on the roller seam welder for a can body 1, each can body 1 is sent to welding rollers along a guide 2. The lower welding roller 3 is disposed on an arm 6 and the upper welding roller 4 is disposed on the arm or a movable rocking body 7. The welding is executed by using an electrode wire 5. The welding force is controlled by a welding force spring 8 fixed in a machine frame 10. The welding force spring 8 exerts the rocking body 7 via a rod 11, further, exerts the upper welding roller 4. By changing preload of the welding force spring 8 with the spring control device 9, the welding force is adjusted to a prescribed position.