The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 28, 1998
Filed:
Apr. 29, 1993
Gordon W Culp, Van Nuys, CA (US);
Rockwell International Corporation, Costa Mesa, CA (US);
Abstract
This invention relates to a multiresonant actuator that moves an object with a minimum of rubbing contact thereby reducing to near zero the heat generated by rubbing contact and cutting the energy loss by this effect to near zero. The invention consists of a traveling wave actuator comprising a vibrator (4) having attached transducers (6a-c) fixed to a base. Traveling wave crests (44) are maintained in contact with a positionable object such as rotor (16) by a predetermined normal force. Traveling wave crests (54) passing along the vibrator (4) forcefully move the positionable object (16) by traction (52). Transducers are electrically segmented into groups. The components of each group are connected in electrical parallel but mechanical series. Groups of a transducer are connected in mechanical series. Each group is electromechanically sinusoidally resonated at a unique frequency, phase, and amplitude by a drive signal from a control means. The vibrator thereby propagates traveling waves that have a nonsinusoidal form. A predetermined wave form produces the least rubbing at the traction contact. The predetermined wave form is used in combination with the Fourier Theorem to prescribe the frequency, phase and amplitude of each transducer group. The vibrator nonsinusoidal wave form is the mechanical sum of sinusoidal constituents. The absence of rubbing proffered by nonsinusoidal traveling waves provides high mechanical efficiency. The use of resonance provides a high electrical efficiency, thereby providing a high actuator system efficiency. Embodiments of the device operate essentially cold, in vacuum without welding, and reliably, as there are few and benign modes of degradation therein.