METHOD OF ULTRASONIC WELDING OF THERMOPLASTIC MATERIALS Russian patent published in 1998 - IPC

FIELD: welding of thermoplastic materials, applicable in ultrasonic welding of parts of thermoplastic materials for obtaining butt and T-joints. SUBSTANCE: in the method of ultrasonic butt welding of parts of thermoplastic material placement of parts to be butt-welded on an anvil is accomplished by a third thermoplastic part introduced between them by ultrasonic vibrations and welding pressure. The introduced third part is placed on the butt line. Welding pressure and ultrasonic vibrations are applied to the introduced part, and the parts contact surfaces are fused. The part is introduced between those to be welded to a specified depth. Then portion of the anvil located under the weld is removed. The part to be introduced is being introduced until a portion of it extends from the weld towards the removed portion of the anvil. Closing weld is formed from the part extended portion. Ultrasonic vibrations are switched off and welding pressure is removed. EFFECT: enhanced quality of welded joint. 6 cl, 5 dwg , 1 tbl