Patent ID: 7598656

Claim:
A piezoelectric ultrasound motor comprising: an oscillator in the form of a piezoelectric plate of length L, height H and width B, said piezoelectric plate having a major surface; and a friction element arranged at the oscillator and elastically pressed against a friction surface of an element to be moved, wherein said friction element is arranged on a long end face of said piezoelectric plate, said piezoelectric plate is divided into two identical parts by a dividing plane that extends perpendicular to said major surface, one of said identical parts including a first asymmetrical generator of an asymmetrical acoustic standing wave, said first asymmetrical generator, when activated, generating an asymmetrical two-dimensional standing wave having a resonant frequency f 0 that deforms said oscillator such that said friction element effects a first movement at a first non-zero angle relative to said long end face, a first driving force impulse being transferred, on account of said first movement, to said element to be moved, and a product of said length L and resonant frequency f 0 is a constant value for a constant ratio of length L to height H and for a constant ratio of length L to width B.