In this work a piezoelectric actuator is described whose stator is composed of two cylindrical steel axes fitted at the surface of a thin piezoelectric membrane. The slider is a beam pressed in contact with two rotors. Each rotor consists of a cylindrical permanent magnet, pressed in contact with the top surface of each axis, by means of magnetic forces. A travelling wave, at the natural flexural vibration frequency of the thin piezoelectric membrane, is excited via piezoelectric effect. The flexural displacement of the membrane is geometrically amplified by the axes, obtaining a wide precessional motion of the axes. The transmission mechanism of the proposed actuator is based on this motion. The actuator is able to give large displacements with a relatively high linear speed (1.21 m/s) and force (0.51 N) by using a commercial piezoelectric membrane (diameter 32 mm, thickness 0.2 mm), driven at relatively low voltage (±18 V). The very small thickness of the overall structure makes this actuator suitable for microsystem applications. A simple analytical approach of the transmission mechanism is reported and experimental measurements are discussed.
A New Linear Piezoelectric Actuator for Low Voltage and Large Displacement Applications
IULA, Antonio;
1999-01-01
Abstract
In this work a piezoelectric actuator is described whose stator is composed of two cylindrical steel axes fitted at the surface of a thin piezoelectric membrane. The slider is a beam pressed in contact with two rotors. Each rotor consists of a cylindrical permanent magnet, pressed in contact with the top surface of each axis, by means of magnetic forces. A travelling wave, at the natural flexural vibration frequency of the thin piezoelectric membrane, is excited via piezoelectric effect. The flexural displacement of the membrane is geometrically amplified by the axes, obtaining a wide precessional motion of the axes. The transmission mechanism of the proposed actuator is based on this motion. The actuator is able to give large displacements with a relatively high linear speed (1.21 m/s) and force (0.51 N) by using a commercial piezoelectric membrane (diameter 32 mm, thickness 0.2 mm), driven at relatively low voltage (±18 V). The very small thickness of the overall structure makes this actuator suitable for microsystem applications. A simple analytical approach of the transmission mechanism is reported and experimental measurements are discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
