The converter converts electrical energy into mechanical vibration energy for ultrasonic waves, and the voltage regulating device is responsible for transmitting the converted mechanical energy to the welding head of the ultrasonic welding machine. The welding head is an acoustic device that transmits mechanical vibration energy directly to the product to be pressed. The vibration is transmitted to the bonding surface through the welding workpiece, and the vibration and friction generate heat to melt the plastic. The vibration will stop when the molten material reaches its interface. Holding the pressure for a short time can cause the melt to generate strong molecular bonds when the bonding surface is solidified. Cycles typically complete in less than a second.