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:
Jun. 07, 2005
Filed:
Aug. 25, 2003
Pei-chung Wang, Troy, MI (US);
Robert T. Thornton, Auburn Hill, MI (US);
Kenneth R. Schmidt, Macomb, MI (US);
Samuel Paul Marin, Oakland Township, MI (US);
Pei-Chung Wang, Troy, MI (US);
Robert T. Thornton, Auburn Hill, MI (US);
Kenneth R. Schmidt, Macomb, MI (US);
Samuel Paul Marin, Oakland Township, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
This invention provides a method of producing a series of substantially uniform spot welds between two metal parts using a servomotor driven movable electrode and an axially opposing fixed electrode. Target values for electrode displacement in producing a weld indentation and electrode squeeze force are determined for the electrodes and workpieces. During welding operations electrode displacement and electrode force measurements are continually taken and compared with the displacement and force target values. While the measured values are within a tolerance range of the target values, welding is continued using the preset parameters. When either or both of the measured electrode displacement or force value falls outside the target range the total welding current is adjusted in small increments to correct the displacement and/or force values and, thereafter, welding is continued using the new total welding current.