Noncontact ultrasonic transportation of small objects in a circular trajectory in air by flexural vibrations of a circular disc

High-speed noncontact ultrasonic transport of small objects using acoustic traveling wave field

“…Kozuka et al reported noncontact manipulation of particles in air by controlling the phase difference between two transducers [5]. We have also reported noncontact transport of small objects in air over long distances using a bending vibrator and a reflector [6] and transport in a circular trajectory [7]. Small objects can be trapped along the horizontal nodal line of an acoustic standing wave generated between a flexural vibrating plate and a reflector.…”

Nonlinear characterization of a single-axis acoustic levitator

“…To overcome this limitation, new levitation techniques have been proposed to manipulate and to transport small samples of solids and liquids. [23][24][25][26][27][28] These new techniques offer many possibilities in the areas of biology, 29 chemistry, 30 pharmacy, 6,31 and in the handling of microelectronic components. 32,33 A possible application is to replace the conveyor belts of modern industries for new types of transportation systems that can transport micro components and substances without contact.…”

“…With this approach, geometric parameters can be optimized before the levitator is built, reducing the number of prototypes during the levitator development. This approach and its variations have been applied in the design of single-axis acoustic levitators 15,16,35,36 and noncontact manipulation systems in air [24][25][26][27][28]37 and in liquids. 38,39 Despite its simplicity and success in designing acoustic levitators, a high intensity sound field is produced in the air gap between the transducer and the reflector, which causes nonlinear effects, such as acoustic streaming 40 and harmonic generation.…”

Ejection of small objects in a noncontact ultrasonic transporter

“…Small objects can be trapped noncontactly by excitation of an acoustic standing-wave field between a vibrating disk and reflector. By shifting the driving condition of the divided electrodes of a PZT ring attached to the disk along the circumferential direction, the nodal lines of the vibrating plate was rotated, and the trapped particle in air could be manipulated with a circular trajectory [3]. In order to apply these techniques in production facilities, the function to transfer the trapped objects to subsequent transportation tracks and switch the transportation direction is required (C in Fig.…”

“…(a) Concept of the noncontact ultrasonic transporter of small objects and (b) configuration of a circular vibrating plate[3].DRIVING CONDITIONS AND MEASUREMENT OF VIBRATION DISTRIBUTIONSThe vibration distribution of each mode measured with a laser Doppler vibrometer (LDV) is shown inFig. 2.…”