Until now. Sanki Co. (Nagoya, Japan) has developed vibratory feeders that are driven by piezoelectric resonators rather than electromagnetic coils. A piezoelectric resonator is a fine ceramic of lead titanate and lead zirconate. The resonator warps one way in response to an electric current in one direction, and it warps the other way in response to current in the opposite direction. Each resonator is paired with a leaf spring. Piezoelectric in-line feeders have two resonator-spring pairs. Piezoelectric bowls have three or four.
Distributed in North America by Mirai Inter-Technologies Systems Ltd. (Richmond Hill, Ontario, Canada), Sanki’s piezoelectric vibratory feeders have several advantages over electromagnetic feeders. Piezoelectric feeders consume 70 percent less energy than comparable electromagnetic feeders. They are unaffected by ambient conditions, and they do not generate heat.