• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2005.07a
• /
• pp.62-63
• /
• 2005

Recently, a tiny piezoelectric linear motor using a vibration made of the transducer has been invented. The motor consists of a shaft, mobile element, and piezoelectric transducer using a piezoelectric radial mode bimorph disk. The fringe of the bimorph disk is fixed firmly which means this area has no degree of freedom. Therefore, the radial mode of the tranducer transfers to the flexurd mode. The mobile elements move along the shaft by the impact force generated by the flexurd mode of the piezoelectric transducer. The piezoelectric ceramic disks have thickness of 0.1 mm and diameter of 3.5 mm. The elastic disk is introduced between two disks of the ceramic, which has thickness of 0.1 mm and diameter of 3.8 mm. The fringe of the elastic disk is fixed by a brass cylinder which height is 1.2 mm. The Pyrex shaft is used which has diameter of 1 mm and height of 10 mm. The motors are operated at their resonant frequencies. The dynamic properties of the motor have been intensively measured and analyzed according to the applied voltage wave forms at the resonant frequencies. As the sawtooth and rectangular voltage waves are applied, the velocity, the thrust force, and the velocity dependence of the mobile position are measured. The dynamic characteristics are also analyzed within a period of each wave using laser vibrometer. The velocity of the mobile is moderately constant along the shaft. The better dynamic characteristics are obtained in the case of applying the rectangular wave.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2000.05b
• /
• pp.61-64
• /
• 2000

An ultrasonic linear motor was composed of a slider and a stator vibrator including piezoelectric material and elastic material. The ultrasonic linear motors mainly consist of an ultrasonic oscillator which generates elliptical oscillations. Elliptical oscillations are generated by synthesizing two degenerated modes. The design of a stator for an ultrasonic linear motor was optimized with respect to vibration mode and direction of vibratory displacement by employing the finite element method. Applying multilayer piezoelectric ceramics. we found larger elliptical oscillations. The motors were designed by varying the width of stator vibrator and the thickness. the length and the position of multilayer piezoelectric ceramics.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.06a
• /
• pp.143-144
• /
• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2007.06a
• /
• pp.109-110
• /
• 2007

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.11a
• /
• pp.233-233
• /
• 2008

A piezoelectric ultrasonic linear motor shaped with 'Butterfly' wings has been developed for thin electronics such as cellular phone and PDA. The butterfly piezoelectric transducer is simply composed of an elastic plate, which includes a tip for energy transfer and two protrusions to fix it, and two piezoelectric ceramics. Contact materials, such as a brass, and steel and alumina can make it possible to improve dynamic properties of the motors over a wide range of tribological conditions. The dynamic properties of the motor have been intensively measured and analyzed according to the applied voltage wave forms at the various frequencies. The results of numerical study and experimental investigation will be used for the future optimization of the actuator and the realization of the advanced ultrasonic motor.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.11a
• /
• pp.192-192
• /
• 2008

This paper represents a piezoelectric ultrasonic linear motor by traveling wave. The motor which is composed of two piezo ceramics, elastic body, and connecting tip is driven by the frictional force between the connecting tip and the linear motion guide. longitudinal and flexural vibrations are made by traveling wave which is generated when the ultrasonic electrical signals with 90 degree phase difference are applied to two ceramics. These vibrations contribute to elliptical motion by mixed mode between longitudinal and transverse mode. A linear movement can be easily obtained by using the elliptical motion. In this paper, the piezoelectric actuator has been intensively simulated by using ATILA to achieve an optimized elliptical motion of it. We could get the elliptical motion from actual experiment through the simulated result.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.11a
• /
• pp.85-88
• /
• 2004

The piezoelectric ceramic is attached between 'L' type guide and 'L' type stator, This motor has rotary motion which is operated by longitudinal and bending mode. The basic structure of the two kinds of type motor that called one stator motor, two stator motor is same but we suggested a few parameters for considering their stator design and characteristics. As a result, the two stator type motor is much more useful than one stator type motor for hi-direction rotation.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• v.3B no.4
• /
• pp.159-164
• /
• 2003

In this paper, a three-dimensional finite element method and construction of equivalent-circuit for a linear ultrasonic motor are presented. The validity of three-dimensional finite element routine in this paper is experimentally confirmed by analyzing impedance of a piezoelectric transducer. Using this confirmed finite element routine, impedance and vibration mode of a linear ultrasonic motor are calculated. Elliptical motion of contact point between vibrator and rail of the linear ultrasonic motor is shown for determination of contact points. By using the finite element method and analytic equations, characteristics of the linear ultrasonic motor, such as thrust force, speed, losses, powers and efficiency, are calculated. The results are confirmed by experiment. Finally, equivalent circuit parameters of the linear ultrasonic motor are obtained using the three-dimensional finite element method and analytic equations.

• Proceedings of the KIEE Conference
• /
• 1999.07d
• /
• pp.1720-1722
• /
• 1999

In this paper, we studied the properties of small-size disk-type ultrasonic motor using travelling wave for the application to the precise control robotic joint motor and fabricated it. The diameter of the ultrasonic motor fabricated was 13mm. Also, the piezoelectric vibrator was constructed by piezoelectric ceramic and elastic material. The piezoelectric ceramic was composed to PZ-PT-PMN which was shown the high electromechanical stability under high vibration level and stainless steel was used as the elastic material in which configuration was disk-type. To conform the capability of application to robotic motor, we measured the change of rotational speed according to applied voltage and applied frequency. As the results, the small-size disk-type ultrasonic motor was able to fabricate, and the revolution speed was 350 [rpm] when input voltage was 55 [Vrms] and applied frequency 160.4 [kHz] under pre-load.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.11a
• /
• pp.379-382
• /
• 2004

In this paper, it is investigated in advance about the PZT-based composition for piezoelectric vibration device. The specimens of piezoelectric ceramics are made of Columbite method. The piezoelectric vibration device by this composition is designed by ATILA(Magsoft) program used FEM(Finite Element Method). The vibration device used for mobile phone must be driven in the frequency of $130{\sim}200Hz$, so the resonant frequency of piezoelectricity must adjust driven frequency bandwidth. The result of analysis by ATILA is appeared dependant property of length, width, thickness and dummy weight about resonant frequency of the piezoelectric vibration device. The size of manufactured actuator is $28{\times}12{\times}0.3mm^3(length {\times}width{\times}thickness)$ and this is bimorph type. The test of manufactured piezoelectric vibration device measure displacement, acceleration and power dissipation. The piezoelectric vibration device has the advantage more than electro-magnetic motor, however the size of manufactured device is larger than electro-magnetic motor.