• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 추계학술대회 논문집
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• pp.275-276
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• 2010

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.627-630
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• 2004

Transducer for linear ultrasonic motor with symmetric and anil anti-symmetric modes was studied. The transducer was composed of two Langevin-type vibrators that cross at right angles with each other at tip. In order to excite two vibration modes, two Langevin-type vibrators must have 90-degree phase difference with each other. As a result, tip of transducers moves in elliptical motion. Elliptical trajectoric of transducer was analyzed by employing the finite element method. From these results, the ultrasonic motor was fabricated and was measured for characteristics. In this paper compared an ANSYS analysis with an experiment results. The no-road maximum speed was 113.1[cm/s].

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.612-617
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• 2000

The vibrational characteristics of Langevin-type piezoelectric torsional transducers have been studied theoretically and experimentally in this paper. The differential equations of piezoelectric torsional motion have been derived in terms of the circumferential displacement and the electric potential. Solutions of the boundary-value problem have yielded the natural frequencies and mode shapes of the transducers. The theoretical solutions have been verified by comparing the numerical results with experimental ones.

• 전기의세계
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• 제30권1호
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• pp.47-54
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• 1981

The fabrication of Langevin type vibrators producing relatively high sonic and ultrasonic energy is described. The dependence of the acoustic output and the frequency characteristics on the thickness of the steel plates and the pressure at the ceramics are investigated. As results, the acoustic output of Langevin type vibrators are relatively high, and the resonant frequency is decreassed by thickening the steel plates and lowering the pressure at the ceramics. Using these results, sonic and ultrasonic vibrator whose resonant frequency is determined can be designed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.634-637
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• 2002

Transducer for linear ultrasonic motor with symmetric and anti-symmetric modes was studied. The transducer was composed of two Langevin-type vibrators. In order to excite two vibration modes, Two Langevin-type vibrators must have 90-degree phase difference with each other. As result, tip of transducers moves in elliptical motion. In this paper, vibration shape of transducer was simulated and The resonant frequency and maximum displacement were calculated using the FEA (Finite Element Analysis).

• 한국음향학회지
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• 제37권6호
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• pp.422-427
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• 2018

본 연구에서는 소형 물체가 음파 정상파의 압력 마디 부근에 소형 물체가 부양하는 정상파 음파 공중부양(standing wave acoustic levitation) 현상에 대해 베르누이 원리를 이용하여 부양의 원인이 되는 음향 방사힘(acoustic radiation force)의 근원과 개형을 기존에 알려진 진동자에서 떨어진 거리에 따른 음향 방사힘의 그래프와 비교함을 통해 개념적으로 설명했다. 이러한 설명을 뒷받침하는 일련의 실험들을 BLT(Bolt-clamped Langevin Type) 초음파 진동자를 이용해서 수행하여, 물체들이 공기의 압력 마디 부근에 부양하고 있음을 확인했고, 물체가 부양하고 있는 상태에서 정상파가 형성되는 조건임을 확인했다. 더불어, 정상파 음파 공중부양 현상에서 부양하는 물체들이 수직하게 일렬로 정렬하는 현상 역시 설명할 수 있었다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권3호
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• pp.123-127
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• 2004

Mode conversion type ultrasonic rotary motor using bolt tightened Langevin type vibrator was studied. Driving frequency of the motor, displacements and elliptical trajectories at tip of the coupler were simulated by finite element analysis program (ANSYS). Speed and torque of the fabricated motor were measured as functions of input voltage and load. As results, from FEA the driving frequency of 40.8[kHz] and useful elliptical trajectories were found. Fabricated motor rotated clockwise at frequency of 38.2[kHz]. Speed and torque of the motor were increased when the input voltage was increased. Maximum speed, torque and efficiency were 75[rpm], 0.14[Nm] and 6.28[％], respectively.

• Transactions on Electrical and Electronic Materials
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• 제5권2호
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• pp.61-65
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• 2004

Bolt-tightened Langevin type vibrators using longitudinal mode of bar were designed and fabricated. In order to amplify the displacement of the tip of the vibrators, stacked ceramics were used and five different shapes of the horns were designed and jointed. Resonant frequencies and vibration characteristics of vibrators and horns were analyzed by ANSYS(finite element analysis computer program), and the displacements of tips of the horns were measured. As results, when the numbers of the stacked ceramics were increased, the displacements of the tips were increased and the driving voltages were decreased. Step l horn (BLT-St1) showed maximum displacement of 36.92 $\mu\textrm{m}$ at 36.7 ㎑ with 45 V$\sub$rms/ and 0.11 A. The displacement amplification ratio was about 5.2. But, the stress of step l horn was concentrated on intersection, where two diameters meet. To lessen the stress, step3 shaped hem is recommended.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.292-295
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• 2002

Transducer for linear ultrasonic motor with symmetric and anti-symmetric modes was studied. The transducer was composed of two Langevin-type vibrators that cross at right angles with each other at tip. In order to excite two vibration modes, two Langevin-type vibrators must have 90-degree phase difference with each other. As a result, tip of transducers moves in elliptical motion. In this paper, elliptical trajectory of transducer was analyzed by employing the finite element method.

• 대한기계학회논문집A
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• 제25권8호
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• pp.1197-1205
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• 2001

The vibrational characteristics of Langevin-type piezoelectric torsional transducers, which consist of a couple of piezoelectric discs and a couple of elastic blocks, have been studied theoretically and experimentally in this paper. The differential equations of piezoelectric torsional motion have been derived in terms of the circumferential displacement and the electric potential. Solutions of the boundary-value problem have yielded the natural frequencies and mode shapes of the transducers. The theoretical solutions have been verified by comparing the numerical results with experimental ones.