Used in ultrasonic welding and joining equipment, ultrasonic resonators typically work with a piezoelectric transducer (which converts an electric signal into an ultrasonic mechanical vibration) and a booster. The ultrasonic resonator engages the parts being assembled and transfers the vibratory energy to them; thus melting the thermoplastics and creating a strong weld.
However, while the energy fed into the resonator should be transmitted directly to the plastic parts, much of it is dispersed, and the efficiency of the device is compromised.
To counter this energy loss, resonators are usually built with elongated slots which extend through the block. But now, Luton based Herfurth UK, claims that by carefully selecting the shape of these slots, the efficiency of the resonator can be further improved by upto 50%.