| Summary: | 碩士 === 國立清華大學 === 工程與系統科學系 === 90 === In this paper, references regarding Langevin vibrators are surveyed. Related principles, their advantages and disadvantages are reviewed. Based on the above mentioned survey and innovative idea in this study, a new single direction motion ultrasonic sliding stage is designed. The novel sliding stage contains two ultrasonic vibration systems. One is actuating system, the other is sliding one. Both systems adopt thin circular nickel alloy sheet (0.1 mm) in which smaller piezoelectric thin-film ceramics (0.1mm) is concentrically adhered at its center. For actuating system, an asymmetric dividing of the nickel plate (90º-120º-150º) is used. On the other hand, for axial sliding, a symmetric dividing (120º-120º-120º) is used. The principle of the asymmetric dividing is used ultrasonic lateral vibrating to actuating stage. Another principle is used ultrasonic axial vibrating to reduced static friction coefficient between sliding system and stage.
During sliding stage designing, finite element software ANSYS is used to simulating the vibration mode in the two systems. The resonant frequencies of the piezoelectric actuators in the two systems are 72 kHz (for actuating system) and 75 kHz (for sliding system) respectively. Since generation heat in this device is quite large, in this paper the heat produced in both systems are dissipated largely from both two actuators to the stage by connecting actuators and the stage.
Under 12V operating voltage on sliding system, the static friction coefficient can reduce from 0.37 to 0.2 in this device. The motion speed of the stage at 0.75N preload applied on actuating system increases from 45 mm/s (without sliding) to 83 mm/s (with sliding).
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