Indirect spot welding method
AssigneeJfe Steel Corporation
InventorsMuneo Matsushita, Rinsei Ikeda
Life of this patent
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Abstract
An oval nugget can reliably be obtained with this indirect spot welding method. In this indirect spot welding method, an electrode end portion of a welding electrode includes a tip of the welding electrode, and as viewed from the tip, the electrode end portion has a two-step dome shape formed by a first curved surface with a curvature radius r1 (mm) located within a range of a circle of radius R (mm) centering on the tip and a second curved surface with a curvature radius r2 (mm). 2√t≤R≤6√t (1), 30≤r1 (2), and 6≤r2≤12 (3), where t is the sheet thickness (mm) of a thinner metal sheet.
Claims4
A method of indirect spot welding for welding a member composed of two overlapping metal sheets, the method comprising:
- holding a spot welding electrode against the two overlapping metal sheets while applying pressure with the spot welding electrode from one side of the member;
- attaching a feeding point to the other side of the member at a location remote from the spot welding electrode;
- and
- allowing current to indirectly flow between the spot welding electrode and the feeding point to form an oval nugget, wherein
- an electrode end portion of the welding electrode includes a tip of the welding electrode, and as viewed from the tip, the electrode end portion has a two-step dome shape formed by a first curved surface with a curvature-radius r1 (mm) located within a range of a circle of radius R (mm) centering on the tip and a second curved surface with a curvature-radius r2 (mm) located at edge of the tip and around the first curved surface, and
- 2√t≤R≤6√t (1)
- 30≤r1≤70 (2)
- 6≤r2≤10 (3)
- where t is a sheet thickness (mm) of a thinner metal sheet of the two metal sheets in the member.
Dependencies are inferred from the claim text.