The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 21, 1998
Filed:
Aug. 11, 1997
Hatsuhiko Oikawa, Futtsu, JP;
Yasuo Takahashi, Futtsu, JP;
Tohru Saito, Futtsu, JP;
Yutaka Okuda, Nagoya, JP;
Kazuo Narita, Nagoya, JP;
Fuminori Matsuda, Toyota, JP;
Katsutoshi Ueno, Toyota, JP;
Goro Watanabe, Aichi-gun, JP;
Nippon Steel Corporation, Tokyo, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
The present invention relates to a resistance welding method suitable for use in spot welding between a steel-base metal sheet, which has been plated for rust prevention purposes, and an aluminum-base metal sheet and aims to permit a current to flow at a high density across the plated steel sheet and the aluminum-clad steel sheet, thereby realizing high-quality welding. An aluminum-clad steel sheet comprised of a steel layer having projections and an aluminum layer is interposed between the plated steel sheet and the aluminum-base metal sheet to be welded to each other. An electrode is energized by a predetermined weld current from an alternating power supply. The current path is limited to the area of the projections, and metallic melt formed by melting of the plating is accommodated between the projections, preventing the current-carrying area from being increased. Consequently, the temperature of the interface of the plated steel sheet and the aluminum-clad steel sheet can be efficiently raised, resulting in the formation of a proper nugget on both sides of the aluminum-clad steel sheet.