Experimental Investigation of a Piezoelectrically Actuated Rotating Parts Feeder

1997 ◽  
Author(s):  
S. H. Chang ◽  
T. W. Yang
Keyword(s):  
Mechanical System ◽  
Electromechanical Coupling ◽  
Laser Interferometer ◽  
Vertical Vibration ◽  
Electromechanical Coupling Coefficient ◽  
Automated Manufacturing ◽  
Electrical System ◽  
Resonance Frequencies ◽  
Displacement Sensitivity ◽  
Small Parts

Abstract The parts feeder provides both horizontal and vertical forces to transfer the small parts between stations in automated manufacturing processes. In this paper, the dynamic characteristics of a piezoelectrically actuated rotating parts feeder was evaluated. The model of the piezoelectric bimorph, the key component of the parts feeder, is formulated under DC and AC excitation. Experiments using laser interferometer, impedance analyzer and spectrum analyzer were conducted to measure displacement sensitivity, resonance frequencies and antiresonance frequencies of the electrical/mechanical system. Relations between driving frequencies and vibration amplitudes under various driving voltages were reported. From experimental results, the resonance frequencies of the mechanical system were identified at 176.6 Hz and 535 Hz. The first resonance and anti-resonance frequencies of the electrical system were found at 176.0 Hz and 177.5 Hz. The electromechanical coupling coefficient for piezoelectric actuator using Mason formula is 13%. Operating at the first resonance frequency, the parts feeder feeds at 17.66 mm/sec with a vertical vibration amplitude of 14.2 μ m.

scholarly journals Analysis on the Radial Vibration of Longitudinally Polarized Radial Composite Tubular Transducer

Sensors ◽  
2020 ◽  
Vol 20 (17) ◽  
pp. 4785
Author(s):  
Xiaoyu Wang ◽  
Shuyu Lin
Keyword(s):  
High Power ◽  
Coupling Coefficient ◽  
Piezoelectric Ceramic ◽  
Electromechanical Coupling ◽  
Electromechanical Coupling Coefficient ◽  
Radial Vibration ◽  
Resonance Frequencies ◽  
Second Mode ◽  
Radial Resonance ◽  
Effective Electromechanical Coupling Coefficient

The radial vibration of a radial composite tubular transducer with a large radiation range and power capacity is studied. The transducer is composed of a longitudinally polarized piezoelectric ceramic tube and a coaxial outer metal tube. Assuming that the longitudinal length is much larger than the radius, the electromechanical equivalent circuits of the radial vibration of a piezoelectric ceramic long tube and a metal long tube are derived and obtained for the first time following the plane strain theory. As per the condition of the continuous forces and displacements of two contact surfaces, the electromechanical equivalent circuit of the tubular transducer is obtained. The radial resonance/anti-resonance frequency equation and the expression of the effective electromechanical coupling coefficient are obtained. Then, the effects of the radial geometry dimension of the transducer on the vibration characteristics are analyzed. The theoretical resonance frequencies, anti-resonance frequencies, and the effective electromechanical coupling coefficients at the fundamental mode and the second mode are in good agreement with the finite element analysis (FEA) results. The study shows that when the overall size of the transducer is unchanged, as the proportion of piezoelectric ceramic increases, the radial resonance/anti-resonance frequency and the effective electromechanical coupling coefficient of the transducer at the fundamental mode and the second mode have certain characteristics. The radial composite tubular transducer is expected to be used in high-power ultrasonic wastewater treatment, ultrasonic degradation, and underwater acoustics, as well as other high-power ultrasonic fields.

Finite Element Analysis and Experimental Studies on the Thickness Resonance of Piezocomposite Transducers

1996 ◽  
Vol 18 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Wenkang Qi ◽  
Wenwu Cao
Keyword(s):  
Finite Element ◽  
Resonance Frequency ◽  
Electromechanical Coupling ◽  
Effective Medium Theory ◽  
Experimental Studies ◽  
Effective Medium ◽  
Electromechanical Coupling Coefficient ◽  
Element Analysis ◽  
Medium Theory ◽  
Resonance Frequencies

Finite element method (FEA) has been used to calculate the thickness resonance frequency and electromechanical coupling coefficient kt for 2–2 piezocomposite transducers. The results are compared with that of the effective medium theory and also verified by experiments. It is shown that the predicted resonance frequencies from the effective medium theory and the unit cell modeling using FEA deviate from the experimental observations for composite systems with a ceramic aspect ratio (width/length) more than 0.4. For such systems, full size FEA modeling is required which can provide accurate predictions of the resonance frequency and thickness coupling constant kt.

Variation of Material Properties of Piezoelectric Ceramics due to Electric Loading Evaluated by Resonance Frequency

2007 ◽  
Vol 345-346 ◽  
pp. 1521-1524 ◽  
Author(s):  
Mamoru Mizuno ◽  
Nozomi Odagiri ◽  
Mitsuhiro Okayasu
Keyword(s):  
Electric Field ◽  
Resonance Frequency ◽  
Lead Zirconate Titanate ◽  
Material Properties ◽  
Electromechanical Coupling ◽  
Domain Switching ◽  
Piezoelectric Ceramics ◽  
Lead Zirconate ◽  
Electromechanical Coupling Coefficient ◽  
Resonance Frequencies

In the present paper, lead zirconate titanate (PZT) and lead titanate (PT) piezoelectric ceramics were subjected to both high electric field (which is higher than the coercive electric field) with low frequency and low electric field with high frequency (which is the resonance frequency). After applying certain electric field systematically, resonance and anti-resonance frequencies and an electrostatic capacity were measured by means of an impedance analyzer, and an electromechanical coupling coefficient, a dielectric constant, an elastic coefficient and a piezoelectric constant were evaluated from the frequencies and capacity measured. Then variation of the material properties in process of time was investigated experimentally, and the dependence of the variation of the properties due to mainly domain switching on conditions of applied electric field was elucidated.

scholarly journals Analysis of a Cascaded Piezoelectric Ultrasonic Transducer with Three Sets of Piezoelectric Ceramic Stacks

Sensors ◽  
2019 ◽  
Vol 19 (3) ◽  
pp. 580 ◽  
Author(s):  
Xiangdi Meng ◽  
Shuyu Lin
Keyword(s):  
Piezoelectric Ceramic ◽  
Electromechanical Coupling ◽  
Ultrasonic Transducer ◽  
Longitudinal Direction ◽  
Electromechanical Coupling Coefficient ◽  
Power Ultrasound ◽  
High Power Ultrasound ◽  
Resonance Frequencies ◽  
Effective Electromechanical Coupling Coefficient ◽  
Good Agreement

To increase the ultrasonic intensity and power of a piezoelectric transducer, a cascaded piezoelectric ultrasonic transducer with the three sets of piezoelectric ceramic stacks is analyzed. The cascaded piezoelectric ultrasonic transducer consists of four metal cylinders and three sets of piezoelectric ceramic stacks in the longitudinal direction. In analysis, the electromechanical equivalent circuit of the cascaded piezoelectric ultrasonic transducer is obtained, as well as the resonance/anti-resonance frequencies equations. By means of an analytical method, when the position of piezoelectric ceramic stacks PZT-2/PZT-3 changes, the resonance/anti-resonance frequencies and the effective electromechanical coupling coefficient of the cascaded piezoelectric ultrasonic transducer have certain characteristics. Several prototypes of the cascaded piezoelectric ultrasonic transducer are manufactured. The experimentally measured resonance frequencies are in good agreement with the theoretical and simulated results. The cascaded piezoelectric ultrasonic transducer with three sets of piezoelectric ceramic stacks presented in this paper is expected to be used in the field of high power ultrasound.

Numerical Modelling of Vibration Characteristics of a Partially Metallized Micro Electromechanical System Resonator Disc

2019 ◽  
Vol 105 (6) ◽  
pp. 1164-1172
Author(s):  
I. Naciri ◽  
A. Rguiti ◽  
L. Elmaimouni ◽  
J. E. Lefebvre ◽  
F. E. Ratolojanahary ◽  
...  
Keyword(s):  
Electromechanical Coupling ◽  
Equations Of Motion ◽  
Electrical Potential ◽  
Electromechanical Coupling Coefficient ◽  
Input Admittance ◽  
Mechanical Displacement ◽  
Resonance Frequencies ◽  
Piezoelectric Structure ◽  
Piezoelectric Disc ◽  
Micro Electromechanical System

In this paper, we report an extension of a polynomial and numerical vibrational characterization of an annular piezoelectric disc resonator partially covered with electrodes. The three governing partial differential equations of motion are solved to provide the frequency response of the piezoelectric disc using a polynomial approach. This method makes use of Legendre polynomials series to express the mechanical displacement components and the electrical potential which are introduced into the equations of motion of the piezoelectric structure. The principal advantage of this method consists of incorporating the electrical source, the boundary and continuity conditions directly into the governing equations by the use of position-dependent physical constants and by a wise choice of the polynomial expansions for the independent variables, the mechanical displacement components and the electrical potential. Both harmonic and modal analyses were studied and are presented. Numerical calculations based on the foregoing method were performed to present resonance and anti-resonance frequencies, electromechanical coupling coefficient, field profiles and electrical input admittance for PIC151 and PZT5A disc resonators with various metallization rates. The high accuracy and reliability of our approach is confirmed via a comparison of our results with their counterparts reported in literature.

Tapered Two-Layer Broadband Vibration Energy Harvesters

2015 ◽  
Vol 137 (3) ◽  
Author(s):  
Xingyu Xiong ◽  
S. Olutunde Oyadiji
Keyword(s):  
Power Density ◽  
Power Output ◽  
Electromechanical Coupling ◽  
Design Strategy ◽  
Dominant Mode ◽  
Vibration Energy ◽  
Electromechanical Coupling Coefficient ◽  
Mass Ratio ◽  
Energy Harvesters ◽  
Resonance Frequencies

Two-layer piezoelectric vibration energy harvesters using convergent and divergent tapered structures have been developed for broadband power output. The harvesters consist of a base cantilevered beam, which is attached to an upper beam by a spacer to develop a two-layer configuration. Two masses are attached to each layer to tune the resonance frequencies of each harvester and one of these masses also serves as the spacer. By varying the positions of the masses, the convergent and divergent tapered harvesters can generate close resonance frequencies and considerable power output in the first two modes. A broadband harvester design strategy is introduced based on a modal approach, which determines the modal performance using mass ratio and modal electromechanical coupling coefficient (EMCC). The required modal parameters are derived using the finite element method. Mass ratio represents the influence of the modal mechanical behavior on the power density directly. Since the dominant mode causes the remaining modes to have smaller mass ratios, smaller EMCC, and poor performance, the design strategy involves the selection of the harvester configurations with close resonances and favorable values of mass ratio initially, and deriving the EMCC and power density of those selected configurations.

scholarly journals Parametric Study of Bolt Clamping Effect on Resonance Characteristics of Langevin Transducers with Lumped Circuit Models

Sensors ◽  
2020 ◽  
Vol 20 (7) ◽  
pp. 1952 ◽  
Author(s):  
Jinhyuk Kim ◽  
Jungwoo Lee
Keyword(s):  
Parametric Study ◽  
Electromechanical Coupling ◽  
Electromechanical Coupling Coefficient ◽  
Model Parameters ◽  
Test Results ◽  
Coupling Coefficients ◽  
Resonance Modes ◽  
At Resonance ◽  
Resonance Frequencies ◽  
Effective Electromechanical Coupling Coefficient

We recently proposed a numerical model using equivalent circuit models to analyze the resonance characteristics of Langevin transducers and design them in a systematic manner. However, no pre-load torque biased by a metal bolt was considered in the model. Here, a parametric study is, therefore, carried out to reveal how model parameters are adapted to incorporate the pre-compression effect into our existing model. Analytical results are compared with corresponding experimental data, particularly regarding the input electrical impedance and effective electromechanical coupling coefficient for the transducer at resonance modes. The frequency response of input impedance is presented as a function of torque, both theoretically and experimentally. For 10.0 N·m bias, for instance, both resonance and anti-resonance frequencies are calculated as 38.64 kHz and 39.78 kHz, while these are measured as 38.62 kHz and 39.77 kHz by the impedance analyzer. The impedance difference between these cases is 14 Ω at resonance and 9 kΩ at anti-resonance, while the coupling coefficients in both cases become 0.238 and 0.239, respectively. Hence, these test results are closely matched with their theoretical values. Consequently, this study provides a quantitative guideline that specifies the pre-loading condition of bolt clamps with proper parameter settings to predict the intended resonance characteristics of Langevin transducers.

scholarly journals Effects of Thermal Annealing on the Characteristics of High Frequency FBAR Devices

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 397
Author(s):  
Yu-Chen Chang ◽  
Ying-Chung Chen ◽  
Bing-Rui Li ◽  
Wei-Che Shih ◽  
Jyun-Min Lin ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Thermal Annealing ◽  
Electromechanical Coupling ◽  
Zno Thin Films ◽  
Electromechanical Coupling Coefficient ◽  
Back Side ◽  
Zno Thin Film ◽  
Frequency Responses ◽  
Sputtering System

In this study, piezoelectric zinc oxide (ZnO) thin film was deposited on the Pt/Ti/SiNx/Si substrate to construct the FBAR device. The Pt/Ti multilayers were deposited on SiNx/Si as the bottom electrode and the Al thin film was deposited on the ZnO piezoelectric layer as the top electrode by a DC sputtering system. The ZnO thin film was deposited onto the Pt thin film by a radio frequency (RF) magnetron sputtering system. The cavity on back side for acoustic reflection of the FBAR device was achieved by KOH solution and reactive ion etching (RIE) processes. The crystalline structures and surface morphologies of the films were analyzed by X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM). The optimized as-deposited ZnO thin films with preferred (002)-orientation were obtained under the sputtering power of 80 W and sputtering pressure of 20 mTorr. The crystalline characteristics of ZnO thin films and the frequency responses of the FBAR devices can be improved by using the rapid thermal annealing (RTA) process. The optimized annealing temperature and annealing time are 400 °C and 10 min, respectively. Finally, the FBAR devices with structure of Al/ZnO/Pt/Ti/SiNx/Si were fabricated. The frequency responses showed that the return loss of the FBAR device with RTA annealing was improved from −24.07 to −34.66 dB, and the electromechanical coupling coefficient (kt2) was improved from 1.73% to 3.02% with the resonance frequency of around 3.4 GHz.

Sb5+ Modified Phase Transition in (Li, Na, K)(Nb1-xSbx)O3 Piezoelectric Ceramics

2016 ◽  
Vol 848 ◽  
pp. 339-343
Author(s):  
Xiao Kun Zhao ◽  
Bo Ping Zhang ◽  
Lei Zhao ◽  
Li Feng Zhu
Keyword(s):  
Phase Transition ◽  
Phase Boundary ◽  
Coupling Coefficient ◽  
Electromechanical Coupling ◽  
Piezoelectric Coefficient ◽  
Electromechanical Coupling Coefficient ◽  
Second Phase ◽  
Phase Transition Temperatures ◽  
Two Peaks ◽  
Planar Mode

The modified behavior of the phase transition temperatures (TO-T and/or TC) between orthorhombic (O), tetragonal (T) and cubic (C) that caused by doping Sb5+ in (Li0.052Na0.493K0.455)(Nb1-xSbx)O3 (LNKNSx) ceramics was reported in the present investigation. The results show that differing from the insensitive TO-T to the Sb5+ content, TC splits into two peaks TCI and TCII when doping Sb5+. The decreased TCI by raising x may be ascribed to the Sb-rich grains and the settled TCII round 480 °C resulting from the Sb-lack ones. The enhanced piezoelectric coefficient d33 value of 263 pC/N and planar mode electromechanical coupling coefficient kp value of 42.5% at x=0.052 can be attributed to the polymorphic phase boundary (PPB) behavior with an appropriate ratio between T and O phases without any second phase.

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