To provide a drive unit capable of driving a conveyor near a resonance mode and eliminating the change of a mechanical system by applying the constitution that the drive unit is treated for the fluctuation of inductance due to a mechanical vibration to determine at least a monetary time for the feed of drive pulses.

A conveyor element shown as a conveyor plate 2 held on a spring 3 is excited to vibrate in the direction of an arrow 4 for the transfer of an object 1. Also, the spring 3 is mounted on a base plate 5 to carry a more flexible ion yoke 6. This yoke 6 forms an air gap with an armature 7 mounted on the conveyor plate 2. Furthermore, a coil 8 is laid on the yoke 6, and driven with drive pulses, so as to excite the mechanical vibration of a system formed out of the spring 3, the plate 2 and the object 1. In this case, the repetitive frequency of the drive pulses is kept at a value approximately equal to the natural frequency of a vibratable mechanical system. An available conveyor natural frequency is generally within the range of approximately 30Hz to 150Hz.