Elimination of tool adhesion in an ultrasonic welding process

US9573221B2 · kind B2 · utility

Assignee

• GM GLOBAL TECHNOLOGY OPERATIONS LLC · US

Inventors

• Michael P. Balogh · Novi, US
• Wayne W. Cai · Troy, US
• Teresa J. Rinker · Royal Oak, US
• Thomas J. Chapaton · Sterling Heights, US
• Peng Lu · Sunnyvale, US
• Eric G. Hartnagle · Rochester Hills, US

Key dates

• Filing date: Jun 15, 2015
• Grant date: Feb 21, 2017
• Expiry date: Jun 15, 2035

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2224/7801
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

A welding assembly includes a sonotrode, cleaning station, and controller. The controller periodically commands clamping of the sonotrode onto the cleaning block, and a transmission of ultrasonic energy into the cleaning block for a calibrated duration sufficient for removing residual amounts of metal from welding pads of the sonotrode. The cleaning block may include an aluminum bar coated with a polymeric material, e.g., porous polyethylene silica or alumina composite. A thin sacrificial layer of an anti-adhesion material, e.g., colloidal silica, may be periodically applied to the welding pads, particularly after a transition from welding a first metal to welding a second metal. The sacrificial layer may be applied via a sponge, a saturated surface, or spraying.