Analytical and experimental study of an ultrasonic horn with a bend angle

An ultrasonic horn is a key component in power ultrasonic longitudinal vibration systems, and the most common horns are designed to allow vibration to travel along a single straight axis. However, change of the propagation direction is required in such applications as ultrasonic cleaning of the inner surface of a bent pipe, ultrasonic-assisted turning for a deep concave workpiece, and ultrasonic bone cutting devices. To address this requirement, this work proposes an angled horn comprising two uniform rods of finite length, which can be excited to resonate in longitudinal mode to change the propagation direction of a longitudinal vibration. Experimental comparison of the working frequencies of the designed and fabricated angled horns validated the effectiveness of the proposed design method. Experimental tests also showed that longitudinal vibration excited by a transducer along the axial direction was successfully transferred from the input end to the output end via the angled horn. Furthermore, the linear vibration characteristics of nine prototype vibration systems (composed of one transducer and nine angled horns) were obtained by measuring the vibration amplitudes induced by various excited voltages applied to the transducer.