A two-way linear piezoelectric vibratory conveyor actuated by a composite sinusoidal voltage input

Abstract

Piezoelectric vibratory conveyors are widely used in many industrial fields such as factory automation. However, there is still a limitation for most cases that the vibratory conveyor can only feed in the designed direction. In today's multitasking intelligent machinery, how to sort different parts from the same feed source and convey them efficiently in different directions remains a challenge to be overcome. This study proposes an innovative design that uses a composite sinusoidal control signal to drive a linear two-stage piezoelectric vibratory feeder. By simply tuning the amplitude and phase of the input composite signal, the conveying velocity and direction can be altered easily. The dynamic characteristics of this feeder were both investigated by theoretical formulation and experimental measurement. It is found that the conveying performance of this feeder is better suited for using the composite signal with two sinusoidal components of double frequency. With the composite control signal synthesized by two sinusoidal components of 237.5 Hz and 475.0 Hz, which were close to the feeder’s first two resonance frequencies to increase the response gain of the structure, and the input voltage of 60 V, which corresponded to the trough’s displacement amplitude of 54.5 m, the measured conveying speeds were +30.8 mm/s and –33.3 mm/s for setting the phase angles 180° and 0°, respectively. The result demonstrates the feasibility of the proposed two-way vibratory feeder design.