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:
Sep. 12, 2000
Filed:
Mar. 29, 1999
Applicant:
Inventor:
Yoshihiro Nagano, Kanagawa, JP;
Assignee:
Dengensha Manufacturing Company Limited, Kanagawa, JP;
Primary Examiner:
Int. Cl.
CPC ...
B23K / ;
U.S. Cl.
CPC ...
219110 ; 219109 ;
Abstract
In a resistance spot welder in which an operation of pressurizing an electrode is conducted by an electric servo motor, an amount of thermal expansion due to production of a weld nugget is detected every moment by reading an encoder which is incorporated in the servo motor. When the detected amount of thermal expansion reaches a preset reference value, it is judged that the weld nugget attains a predetermined strength, thereby stopping a current supply. According to this configuration, a predetermined amount of input heat is ensured, so that an excellent welding quality is surely obtained.