Resonant-Type Smooth Impact Drive Mechanism Actuator with Two Langevin Transducers
A smooth impact drive mechanism (SIDM) is a unique piezoelectric actuator that is widely used as a camera focusing mechanism, cell phone lens movement mechanism, etc. This principle enables a compact driving mechanism; however, it cannot generate high-speed movement because a soft-type multilayered piezoelectric transducer (PZT) is utilized at off-resonant movement. This paper proposes a resonant-type SIDM actuator driven with hard-type PZTs to realize high-speed and powerful operation. The fundamental principle is also based on the conventional SIDM; therefore, a saw-shaped movement is required. To generate a high-power ultrasonic output, two Langevin transducers are adopted instead of a soft-type multilayered PZT. One Langevin transducer was a stator and the other was slider whose tip was adhered to a carbon fiber reinforced plastic (CFRP) rod. The CFRP rod was connected to the stator transducer with the frictional force. To obtain quasi-saw-shaped vibration, the longitudinal vibration for each Langevin...