Patent · US Expired

Sheet-to-tube resistance spot welding using servo gun

US7060929B2 · kind B2 · utility

4Cited by
9References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 24, 2004
Grant dateJun 13, 2006
Priority date
Expiry dateJul 10, 2024

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB23K11/115
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A method of spot welding a sheet overlapped to a tube with a servomotor-driven electrode applying a clamping force to the sheet. Over a first clamping time interval, the clamping force is increased to a first force level, at which point a welding current is applied to weld the sheet and tube together for a welding time interval. The first force level is maintained for a second clamping time interval, after which the clamping force is reduced to a second force level over a third clamping time interval and is maintained for a fourth clamping time interval. The welding current is removed upon expiration of the welding time interval and the clamping force is simultaneously reduced over a fifth clamping time interval, after which the electrode is disengaged from the sheet. The reduction in clamping force during the welding cycle reduces cracking of the spot weld.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.