Considering that longitudinal vibrator is made of t he whole pieces of piezoelectric wafer a nd it can be easily designed,so the desi gn of piezoelectric vibrator is mainly a bout the torsional vibrator.
Based on the working principle of the micro-pump actuated by the piezoelectric wafer,this paper introduces a piezoelectric micropump with the new structure based on the lamination,which adopts the cantilever check valve. In the laboratory the prototype pump has been designed and manufactured,the systematic experiment research has also been done,and the optimization scheme has been put forward,which adopted the muti-chamber series connection structure to improve the performance of the micro-pump.
The difficult problems for making complex piezoelectric vibrator,such as the selection for the piezoelectric discs and sticking materials, making technique, the affection and control of sticking layer thickness, etc. are studied and solved.
The acoustic internal friction of iron vibrating transversely in a steady magnetic held was measured by means of Rochelle salt (NaKC_4H_4O_6 ·4H_2O) crystal plates, the frequency of vibration used was 1633 cycles/sec.
Experiments and Performance Analysis of Piezoelectric-ActuatorBased on the understanding and mastering of the basic piezoelectric theory and the performance of piezoelectric materials, various piezoelectric actuators are studied.
Described is the development of high-impedance backing composites (up to 25.1×106 kg·m-2·s-1) by using a kind of simple compressor. Working in cooperation with PZT-5 or PZT-6, it gives a pulse width of 1.5 cycles.
GHz high performance SAW voltage control oscillator using STW filter on LiNbO 3 substrate as the frequency control element is described in this paper. The voltage control bandwidth of the oscillator is larger than 25 MHz,phase noise less than -80 dBc/Hz@1 kHz and harmonic suppress 37 dB with the size of smaller than 50 mm×25 mm×10 mm.
The feasibility of wave parameter optimization by using various materials of the layers and piezoelectric substrate is demonstrated with particular examples.
The electrode current is obtained via the rigorous calculation of the SAW-related charge in the piezoelectric substrate and of the charge induced by the former charge in the transducer electrodes.
The space charge coupled interaction of surface acoustic waves (SAW) propagating on a piezoelectric substrate with a semiconductor surface placed in proximity gives rise to SAW attenuation.
A method is proposed for calculating an electric field in a thin piezoelectric wafer taking into account the injection of electrons from a metal electrode into an insulator.
These peculiarities are discussed and illustrated by numerical results for quartz and PZT 4 piezoelectric discs radiating into water, air and liquid hydrogen.
It was also found that the use of Chladni figures on the piezoelectric discs as an indication of the smoke detector sounding was not an accurate predictor.