A NEW CLASS OF WAVE-GUIDES FOR ULTRASONIC WELDING OF PLASTICS

A new class of waveguides in the form of extended rectangular plates s upporting planar vibrations with pistonlike displacements on long side s is proposed. The waveguide configuration is chosen to provide the pr edominance of the thickness resonance mode of an infinite layered wave guide with thickness equal to the plate height. These displacements ar e shown to correspond to the centers of the second series of plateaus in the resonance spectrum of symmetric vibrations of the rectangular p late. A possibility to significantly enhance the uniformity of displac ements on plate edges by attaching half-wave correcting rods to the pl ate is established by means of finite-element modeling. Plates of cons tant and variable thickness are considered.