Michael S Stefansen

US Patent:

20090272480, Nov 5, 2009

Filed:

May 4, 2009

Appl. No.:

12/434818

Inventors:

William P. Simon - New Milford CT, US
Michael S. Stefansen - Danbury CT, US

International Classification:

B29C 65/02
B23K 31/12
B23K 20/10

US Classification:

156 64, 1565801, 228 11, 156378, 228104

Abstract:

A system for performing an ultrasonic staking operation in order to join a first part having a post protruding therefrom and a second part having a hole through which the post is passed includes a horn having an end vibrating at a frequency in the ultrasonic range and a motion system operatively connected to the horn, the motion system being capable of selectively moving the horn toward and away from the parts. The motion system moves the horn, with the end of the horn in contact with the post, toward the parts at a first speed such that the ultrasonic vibrations of horn cause melting of the post, and once a determination is made that the end of the horn has contacted a surface of the second part, the motion system moves the horn toward the parts at a second speed, the second speed being slower than the first speed.