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. 22, 2003
Filed:
Aug. 29, 2001
Hisanori Okamura, Tokai-mura, JP;
Masahiko Sakamoto, Hitachi, JP;
Kinya Aota, Hitachi, JP;
Isao Funyu, Takahagi, JP;
Kouichi Watanabe, Hitachi, JP;
Akihiro Sato, Hitachi, JP;
Masakuni Ezumi, Kudamatsu, JP;
Yasuo Ishimaru, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
The invention intends to reduce a frequency at which defects occur in a welding region during friction stir welding, and to improve the reliability of the welding region. The invention resides in a friction stir welding apparatus wherein a distance to the surfaces of the workpieces is detected by a detector, a change of the detected distance is found by a signal processing device, and a tool is rotated by a rotation driving device in a state where a vertical driving device is controlled by a control device so as to suppress the found change, whereby a plastic fluidity of the workpieces is caused to accomplish joining of the workpieces.