Ultrasonic and vibration welding of thermoplastics using a vibratable tool

A system for welding, staking, swaging, forming or degating of a thermoplastic workpiece, comprising:

• a vibratable horn having a face;
• a thermoplastic workpiece having an upper surface with a three-dimensional contour;
• and
• means for transferring energy from the vibratable horn to the thermoplastic workpiece without contact between the vibratable horn and the thermoplastic workpiece to induce welding, staking, swaging, forming or degating of the thermoplastic workpiece;
• wherein the means for transferring energy includes a lower surface having a three-dimensional contour that is complementary to the three-dimensional contour of the upper surface of the thermoplastic workpiece.

A method of welding, staking, swaging, forming or degating of a thermoplastic workpiece, comprising:

• positioning a vibratable tool between a vibratable horn and a thermoplastic workpiece, the vibratable horn having a face, the vibratable tool having an upper surface and a lower surface;
• moving at least one of the vibratable horn and the thermoplastic workpiece relative to the other so the lower surface of the vibratable tool contacts an upper surface of the thermoplastic workpiece while the upper surface of the vibratable tool contacts the face of the vibratable horn;
• and
• energizing the vibratable horn to transfer energy from the vibratable horn through the vibratable tool to the thermoplastic workpiece to induce welding, staking, swaging, forming or degating of the thermoplastic workpiece;
• wherein the upper surface of the thermoplastic workpiece has a three-dimensional contour;
• and
• wherein the lower surface of the vibratable tool has a three-dimensional contour that is complementary to the three-dimensional contour of the upper surface of the thermoplastic workpiece to permit substantially uniform contact between the lower surface of the vibratable tool and the upper surface of the thermoplastic workpiece during the energizing.