Piezoelectric quasi-resonance linear motors based on acoustic standing waves with combined resonator

A system comprising a piezoelectric motor, said piezoelectric motor comprising:

• a piezoresonator body having opposing upper and lower surfaces and opposing front and back surfaces, said front and said back surfaces being parallel to a first and second longitudinal axes of said piezoresonator body, said first and said second longitudinal axes being perpendicular to each other, and said upper and said lower surfaces being parallel to said first longitudinal axis and perpendicular to said second longitudinal axis;
• at least one common electrode disposed on said back surface;
• a plurality of electrodes disposed on said front surface along said first longitudinal axis, said plurality of electrodes comprising one or more pairs of excitation electrodes;
• and
• a plurality of contact elements disposed on said upper and said lower surfaces at contact locations along said first longitudinal axis, each of said plurality contact elements associated with one of said pairs of excitation electrodes;
• wherein said piezoelectric body has a even order natural resonance frequency (ν2) for a standing longitudinal wave in a direction of said first longitudinal axis, a first order natural resonance frequency (νi) for a standing longitudinal wave in a direction of said second longitudinal axis, and wherein:
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A piezoelectric device comprising:

• a piezoresonator body having opposing first and second surfaces and opposing third and fourth surfaces, said first and said second surfaces being substantially parallel to first and second longitudinal axes of said piezoresonator body, said third and said fourth surfaces being substantially parallel to said first longitudinal axis and substantially perpendicular to said second longitudinal axis, and said first and said second longitudinal axes being substantially perpendicular to each other;
• at least one common electrode disposed on said back surface of the piezoresonator;
• a plurality of electrodes disposed on said first surface, said plurality of electrodes comprising one or more pairs of excitation electrodes, each of said pairs of excitation electrodes comprising a first electrode and a second electrode positioned along a first direction along said first longitudinal axis;
• and
• one or more contact elements disposed on at least one of said third and said fourth surfaces at one or more contact locations, each of said contact locations at least partially aligned between said first and said second electrodes of one of said pairs of excitation electrodes;
• at least one driven element in friction contact with said plurality of contact elements;
• and
• an excitation source connected to the one common electrode and to said pairs of excitation electrodes;
• wherein said piezoelectric body has a first order natural resonance frequency (νi) for a first standing longitudinal wave in a direction of said second longitudinal axis and a even order natural resonance frequency (ν2) for a second standing longitudinal wave in a direction of said first longitudinal axis, wherein:
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• wherein said excitation source is configured for applying an alternating voltage to said common electrode and one of said first and said second electrodes of each of said pairs of excitation electrodes to simultaneously generate said first standing longitudinal wave and said second standing longitudinal wave in said piezoelectric body.