Autoresonant vibro-impact system with electromagnetic excitation

Vibration is often used to improve the performance of material handling, processing or separation machinery. Linear suspension and sinusoidal motion of moving parts are usually employed in the design of these machines. A typical example would be vibrating screens used to grade gravel in sand and gravel extracting systems. A dramatic improvement in performance can be achieved if nonlinear suspension, with limiters to provide a vibro-impact motion, can be established. Unfortunately, effective vibro-impact resonant behaviour cannot be sustained in practice with traditional forced excitation due to the system sensitivity to small changes in load. Effective vibro-impact regimes, however, can now be achieved using the concept of autoresonant systems. An electromagnetic drive actuator is a simple and reliable means of vibration excitation. Importantly, this drive allows for an expansion of the autoresonant approach towards high-power applications. This paper introduces a novel autoresonant machine design, which has been developed for this type of actuator. Autoresonant operation is demonstrated using an experimental rig of vibro-impact shale shaker with electromagnetic actuator.