Patent ID: 9486955
Filing Date: 2016-11-08
CPC Classification: B23K,B29C

Claim Text:
1. An ultrasonic welding system comprising: a movable ultrasonic welding stack to move and to apply vibrational energy to at least one workpiece responsive to control inputs; an electrically powered linear actuator including a servo motor and a movable element coupled to the ultrasonic welding stack, the electrically powered linear actuator causing, responsive to control inputs, the movable element and the ultrasonic welding stack to move with a controlled force, speed, or force and speed; a controller to provide control inputs to the electrically powered linear actuator to control an output of the electrically powered linear actuator; and at least two sensors to sense control variables and to output signal outputs corresponding to the control variables to the controller, wherein one of the control variables is a function of force or pressure applied by the servo motor or to the at least one workpiece; wherein the controller causes the ultrasonic welding stack to apply a predetermined positive initial force to the at least one workpiece prior to the initiation of the welding operation and to initiate subsequent movement of the ultrasonic welding stack, following the initiation of the welding operation, only after the signal outputs from the at least two sensors indicate that a combination of the control variables satisfies a predetermined condition.