Noncontact Ultrasonic Motor with Two Flexural Standing Wave Vibration Disks

Abstract

Apparatus is described for obtaining the curves relating area with time in photographic between-lens shutters. A set of separated and illuminated apertures fitted with neutral glass filters passing certain standard fractions of the light is imaged by a lens on film wrapped round a revolving drum, the shutter acting as a diaphragm for the lens. The film is thus exposed in bands along its length. An exposure is made, with the shutter set fully open, for one revolution of the drum. The above apertures are then replaced by a second set without neutral filters, each of these apertures fitting exactly between the spaces previously occupied by two apertures of the previous set. An instantaneous exposure of the shutter is then made during another revolution of the drum, During the whole of this exposure a time scale is impressed on the film by subsidiary apparatus. After development the points at which adjacent bands have the same density are found. These give the times at which the area of opening of the shutter was equal to the standard fractions of its full aperture. Various features of the apparatus are discussed, and particulars are given of the method of calibrating the neutral filters and of tests carried out on shutters for which curves relating area with time could be calculated.

Improvement of Characteristics of Noncontact Ultrasonic Motor Using Acoustically Coupled Two Air Gaps

“…19) If the viscous torque induced by the acoustic streaming adds to not only the lower but also the upper surface of the rotor like the standingwave-type motor, the rotational characteristics of the traveling-wave-type motor will surely improve. We experimentally tried to improve revolution speed by attaching the acoustic reflector over the rotor of the noncontact ultrasonic motor that uses the traveling wave vibration disk.…”

Development of multi-degree-of-freedom noncontact transportation using holding force in near-filed acoustic levitation and consideration of factors of unstable operation

“…1,2) Because NFAL acts on a levitated object in non-contact, this has been studied for applications such as non-contact transportation technology for glass liquid crystal substrates and silicon wafers, or noncontact ultrasonic motor. [3][4][5][6][7][8][9] When the stator is densely arranged in a plane, a tabular object, which is larger than the width of the vibration board, is transported to the vibrator having a larger vibration amplitude and transported in a stepped. 10) That is, a noncontact-stepping ultrasonic motor (NCS-USM) is realized.…”

Numerical Analysis on Chaotic Vibration of Drive System for a Movable Tooth Piezoelectric Motor

“…In 2009, a noncontact piezoelectric motor with two flexural standing wave vibration disks was proposed by Yamayoshi et al, and the rotating speed of which is up to 2000 rpm at a very low driving voltage of 3 V [12]. In 2012, a noncontact piezoelectric actuator with spherical rotors was designed by Chen et al, and a maximum rotational speed of 521 r/min was obtained under excitation voltage of 300 V [13].…”