An ultrasonic welding system includes a motion control system that is coupled to and that causes controlled movement of an ultrasonic welding stack, in accordance with control inputs that are based on one or more control signals that are received from one or more sensors. The motion control system initiates a welding operation, subsequent to which an initial motion delay occurs until a predetermined condition is satisfied. Subsequently, in response to the predetermined condition being satisfied, the ultrasonic welding stack is caused to move in accordance with a weld profile. Subsequently, in response to an occurrence of a predetermined delay initiating condition, the ultrasonic welding stack is caused to stop motion and to maintain a stationary position. Subsequently, in response to an occurrence of a predetermined delay terminating condition, motion of the ultrasonic welding stack is resumed in accordance with the weld profile.

An ultrasonic welding system includes a motion control system that is coupled to and that causes controlled movement of an ultrasonic welding stack, in accordance with control inputs that are based on one or more control signals that are received from one or more sensors. The motion control system initiates a welding operation, subsequent to which an initial motion delay occurs until a predetermined condition is satisfied. Subsequently, in response to the predetermined condition being satisfied, the ultrasonic welding stack is caused to move in accordance with a weld profile. Subsequently, in response to an occurrence of a predetermined delay initiating condition, the ultrasonic welding stack is caused to stop motion and to maintain a stationary position. Subsequently, in response to an occurrence of a predetermined delay terminating condition, motion of the ultrasonic welding stack is resumed in accordance with the weld profile.

An ultrasonic welding system, for welding together two workpieces wherein at least one of the workpieces includes a polymeric composite, comprising an energy applicator positioned along an action axis so that, in operation, ultrasonic vibrations transmitted from the energy applicator during a welding routine, are transmitted to the workpieces generally at and/or adjacent the axis. The system also includes a primary, course-control, actuator positioned along action axis so that a first load, output by the primary actuator, acts along the system action axis. The system further comprises a secondary, fine-control, actuator positioned along the system action axis so that a second load output, by the secondary actuator, acts along the axis. And the system comprises a controller for providing first command signals and second command signals to the primary actuator and second actuator to control them to effect loads on the workpieces, during the welding routine and along the axis.

A method and a connecting element for joining two components, at least one of which is made of a fiber-reinforced composite, are proposed.