METHOD OF ULTRASONIC WELDING OF THERMOPLASTICS Russian patent published in 2004 - IPC

FIELD: plastics welding. SUBSTANCE: the invention presents a method of plastic welding, in particular the method of welding of thermoplastic polymeric materials, that may be used in aircraft industry at manufacturing belts, halyards, shroud lines, etc. out of capron straps and cords, at manufacturing mats and brushes out of synthetic monofilaments, in production of plastic household goods and consumer goods. The method of ultrasonic welding of thermoplastics provides, that before squeezing of welded pieces they switch on and start to measure a counter movement of a waveguide and a support with respect to each other. The measurement is going on in a period of the pieces squeezing between the waveguide and the support by an increasing pressure of squeezing. At reaching by the counter movement of the given value this movement is fixed and the pressure of squeezing is removed. Then the ultrasonic oscillations and welding pressure are switched on and the welding cycle is ended in the given mode. The invention ensures an increase of quality of welded joints at the expense of provision of permanence of the beginning of the process of welding with stationary from a cycle to a cycle parameters by a strict differentiation of a material squeezing process and process of a welding, and also differentiation of parameters of squeezing and a welding. EFFECT: the invention ensures an increase of quality of the welded joints. 1 dwg