• Title, Summary, Keyword: Length extensional vibration mode

Search Result 13, Processing Time 0.036 seconds

Effects of Three Side Ratios of the Rectangular Substrate on the Resonant Characteristics of the Ultra-small Size Resonator Using Its Length Extensional Vibration (사각 기판의 길이진동을 이용하는 초소형 공진자에 있어서 사각 기판의 세변의 길이비가 공진특성에 미치는 영향)

  • 이개명;한성훈;김병효
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.13 no.11
    • /
    • pp.932-937
    • /
    • 2000
  • The length extensional vibration mode of a piezoelectric ceramic substrate is used in fabricating the ultra-small size resonators and filters. In general, the three side ratios of the rectangular substrate affect the resonant characteristics of the resonator using its length extensional vibration. In this paper, their relationships are studied. We know that changing the ratio of its length to its width makes possible to change the resonant frequency of the width vibration without degrading the length extensional vibration. And frequency constant for length extensional vibration becomes slightly small as the substrate thickness becomes thin, but it does not change as its length changes. Electro-mechanical coupling factor for length extensional vibration, k$\_$31/ does not change as its length changes within length/width$\geq$4, but it becomes small as its width increases.

  • PDF

Effects of three side ratios of the rectangular substrate on the resonant characteristics of the ultra-small size resonator using its length extensional vibration (사각 기판의 외형비가 길이진동을 이용하는 초소형 공진자의 공진특성에 미치는 영향)

  • 한성훈;김병효;이개명
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.877-880
    • /
    • 2000
  • The length extensional vibration mode of a piezoelectric ceramic substrate is used in fabricating the ultra-small size resonators and filters. In general, the three side ratios of the substrate effect the resonant characteristics of the resonator using its length extensional vibration. In this paper, their relationships are studied. We know that changing the ratio of its length to its width makes possible to change the resonant frequency of the width vibration without degrading the length extensional vibration.

  • PDF

A Study on Design and Analysis of Piezoelectric Transformer for Resonance Mode (공진모드의 변화에 따른 압전변압기의 특성에 관한 연구)

  • 정현호;이상기;박태곤;김명호;이원재
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.432-435
    • /
    • 2000
  • This paper present a new sort of multilayer piezoelectric ceramic transformer for the application to AC-adapters. This piezoelectric transformers operate in the second and third length extensional vibration mode. And the output performance of two types of piezoelectric transformers are compared by ANSYS, which is one of the FEM analysis program. As a result the minimum displacement was occurred at the two points in second length extensional vibration mode and three point in third length extensional vibration mode. One is the middle of input and the other is middle of output parts. And output voltage was inversely decreased by increasing number of output layers. Also The third mode type is shown higher power transition ratio than the second mode type.

  • PDF

Temperature stability for length extensional vibration of $Pb(Zr_{0.56}Ti_{0.44}O_{3}+x[wt%]Cr_{2}O_{3})$ceramics ($Pb(Zr_{0.56}Ti_{0.44}O_{3}+x[wt%]Cr_{2}O_{3})$세라믹스의 길이진동에 대한 온도안정성)

  • 현덕수;한성훈;이개명
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.881-884
    • /
    • 2000
  • Recently mobile communication fields need piezoelectric ceramic resonators and filters as possible as small. The length-extensional vibration mode of a rectangular piezoelectric cesamic plate has the advantage of the small size, but the mode has not been studied sufficiently because it was not used extensively until now. In this paper, PZT + x[wt%l $Cr_20_3$ ceramics with rhombohedra1 phase were fabricated. And temperature stability for the mode of the ceramic specimen was investigated. Contrary to our expectations, addition of the stabilizer, $Cr_20_3$ did not promote the temperature stability for the mode in the PZT ceramic specimen with rhombohedra1 phase.

  • PDF

Temperature Stability of Length-Extensional Vibration Modes in PZT Ceramics (PZT세라믹스에 있어서 길이진동모드의 온도안정성)

  • 이개명;현덕수
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.14 no.9
    • /
    • pp.726-730
    • /
    • 2001
  • Temperature stabilities of dielectric constraints and resonant frequencies of the substrates are very important in piezoelectric ceramics oscillators and filters. In this study, it was investigated temperature stability of the length-extensional vibration mode of Pb(Zr$\_$y/Ti$\_$1-y/)O$_3$+x[wt%]Cr$_2$O$_3$ ceramics. The mode can be utilized in fabricating ultra-small 455 kHz IF devices. Addition of Cr$_2$O$_3$ in morphotrophic phase PZT decreased the variations of dielectric constant, electro-mechanical coupling factor k$\_$31/ and resonant frequency by thermal shock. As additive weight of Cr$_2$O$_3$increased, the temperature coefficient of resonant frequency changed from positive number to negative one. And the composition tith temperature coefficient of resonant frequency was shifted to the one with increased Cr$_2$O$_3$ additive weigh by thermal aging.

  • PDF

A Study on Temperature Stability of PZT Piezoelectric Ceramic Resonators using Length Extensional Vibration (길이진동을 이용하는 PZT계 세라믹 공진자의 온도안정성에 관한 연구)

  • Han, Seong-Hun;Lim, Dae-Kwan;Lee, Gae-Myoung
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.885-887
    • /
    • 1999
  • The piezoelectric ceramic resonator using length extensional vibration rather than contour extensional vibration in terms of the size is suitable for personal portable communication. In this paper, $Pb(Zr_{x}Ti_{l-x})O_{3}$ + r[wt%]$Cr_{2}O_{3}$ ceramics, x=0.56, 0.53, 0.50 (ie, Zr/Ti ratios = 56 /44, 53/47, 50/50) r=0, 0.3[wt %], were fabricated. Temperature stability of length extensional vibration mode of those specimens was investigated. Both crystal structure with rhombohedral phase in the case of no addition of $Cr_{2}O_{3}$ and crystal structure with morphotrophic phase boundary in case of additions of 0.3[wt %]$Cr_{2}O_{3}$ had the vest temperature stability and improved temperature stability through thermal aging.

  • PDF

Step-Down Voltage Properties of Piezoelectric Transformer with Extensional Vibration Mode (Extensional 진동 모드를 이용한 압전 트랜스포머의 감압 특성)

  • Choi, Ji-Hyun;Bang, Kyu-Seok
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.652-655
    • /
    • 2003
  • In this paper, step-down piezoelectric transformer is studied. The piezoelectric transformer, made of lead zirconate titanate solid solution ceramic, is operated by a fundamental contour-extensional vibration mode. The transformer of 14mm length, 14mm width and 4.5mm thickness was made up two shape(Type I and II). The resonant frequency (fr) is 144kHz and 128kHz at the load resistant of $7.5{\Omega}$ that is a similar to calculating matching impedance. The gain (G) obtained 0.19 and 0.08 at each resonant frequency, when applied input voltage is 25V. The temperature difference with the variation of load resistant was increased with increasing load resistant and was the lowest at $7.5{\Omega}$ near the matching of output impedance.

  • PDF

Design and FEM Analysis of Piezoelectric Ceramic Transformer for Low-Voltage Step-Down Application (강압용 압전변압기의 설계 및 유한요소해석)

  • Jueng, Hyon-Ho;Lee, Sang-Ki;Park, Tae-Gone;Lee, Won-Jae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.70-73
    • /
    • 2000
  • This paper present a new sort of multilayer piezoelectric ceramic transformer for AC-adapter. This piezoelectric transformer operates in the second longitudinal vibration mode. The output voltage of the multilayer piezoelectric transformer was simulated using ANSYS, that is one of the FEM analysis program. As results, the minimum displacement was occurred at the two paints where one is the middle of input and the other is middle of output side in second thickness extensional vibration mode. And output voltage was inversely decreased by increasing number of output layers. 缀Ѐ㘰〻ሀ䝥湥牡氠瑥捨湯汯杹

  • PDF

Measurement of all the Elastic, Dielectric and Piezoelectric Properties of PMN-PT Single Crystals (공진법을 이용한 PMN-PT 단결정의 탄성, 유전, 압전상수 측정)

  • 이상한;이수성;노용래;이호용;한진호
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.17 no.1
    • /
    • pp.31-38
    • /
    • 2004
  • PMN-PT, a piezoelectric single crystal, has many useful applications such as sensors and actuators. In this paper, all the elastic, piezoelectric, and dielectric constants of the PMN-32%PT single crystals were measured by the resonance method. For the rhombohedral symmetry, a total of twelve independent material constants were measured such as six elastic compliance constants at constant electric field, two dielectric constants at constant stress, and four piezoelectric constants d. Seven sets of crystal samples of each different geometry were prepared for the measurement of length-thickness extensional, thickness extensional, radial, length extensional and thickness shear modes of vibration, respectively. In order to check the validity of the measurement, experimental impedance spectrum of the PMN-PT crystal was compared with numerical data spectrum calculated with the measured material constants. The good agreement between the two spectra confirmed validity of the results in this paper.

Aging of Length-Extensional Vibration Modes in PZT Ceramics (PZT 세라믹스에 있어서 길이진동모드의 경시변화)

  • 이개명;김병효;황충구;강찬호;현덕수
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.15 no.10
    • /
    • pp.858-864
    • /
    • 2002
  • Aging stabilities of the operating frequency of piezoelectric devices such as filter, oscillator and discriminator are very important. In this study it was studied aging stabilities of the length-extensional vibration mode of Pb(Zr$\^$y/O$_3$+ x[wt%]Cr$_2$Co$_3$ ceramics. PZT ceramics in morphotropic phase boundary have higher aging rates of k$\_$31/ and resonance frequency than those in tetragonal phase or rhombohedral phase. Thermal aging moves the composition with maximum aging rate to Zr-rich side in Cr$_2$O$_3$ not added PZT system. In the PZT system, aging rates of k$\_$31/ and resonance frequency for first 30 days are bigger than those for the following 90 days. Thermal aging decrease those for first 30 days. Aging rate of resonance frequency of the ceramics with x=0.1, y=0.53 and x=0.3, y=0.53 increased by thermal aging.