Abstract: Traveling-wave piezoelectric motor comprising at least one stator (1), two groups of piezoelectric elements consisting of ceramic rods (5) polarized independently of one another, arranged perpendicularly to the stator and excited by an alternating current with a phase shift of .pi./2 between the groups so as to generate a deformation in the form of a traveling wave on the surface of the stator (1), and at least one rotor (2, 3) in the form of a disk. The stator is in the form of a wheel consisting of a peripheral annulus over which the piezoelectric elements are distributed, of a central hub and of linking arms intended to transmit an axial pressure exerted on the hub to the annulus.It is thus possible to compress the rods with a much greater force than that applied to the rotor. This prestress has the effect of limiting the spread in the resonant frequencies.

Abstract: Traveling-wave piezoelectric motor comprising at least one rotor (20, 21), at least one annular stator (27, 28) and two groups of piezoelectric elements (29) dispersed around the stator, in permanent contact with the stator and excited by an alternating current with a .pi./2 phase shift between the groups so as to produce, at the surface of the stator, a traveling wavelike deformation. Piezoelectric elements consist of mutually independent polarized ceramic bars (29) arranged perpendicularly to the stator and each connected to the stator by an articulation (14).