雙層壓電式超音波馬達之研究

Abstract

隨著科技的發展，各種消費性電子產品普遍為人類所使用，如何讓這些產品體積更小、重量更輕成為產品成功與否的關鍵之一。在各類產品之中，微小化機械產品的需求也逐漸增加。如各種相機產品，其對焦、變焦系統更是仰賴各類如線圈馬達等致動器做為鏡片移動的重要原件。但是傳統馬達的各種缺點成為相機小型化的一大障礙。因此，利用超音波馬達高速、設計多變的優點利用在相機對焦、變焦系統中成為超音波馬達的一個新的應用。本研究的研究目標便是研發一種體積小、重量輕、製造與設備成本低的新超音波馬達。 本研究利用雙層壓電振動片作為雙層壓電式超音波馬達的主要結構，配合氧化鋁的耐磨特性作為雙層壓電式超音波馬達的接觸點與被驅動表面的摩擦材質。並利用ANSYS作有限元素法模態來模擬與驗證其操作模態。在一系列量測其最大驅動速度、可承受的最大負載與能量轉換效率的研究後，完成了體積小、重量輕、設計簡單、生產與設備簡單的高效能超音波馬達。其外型最大尺寸僅為9 mm * 3 mm * 2.3 mm，最大速度高達255 mm/s，最大可承受負載高達20.5 g。其各項效能對體積標準化後與文獻中的各種超音波達作比較，可以發現雙層壓電式超音波馬達擁有十分優異的效能。未來應用層面廣泛。

With the advance of technology, many kinds of consuming electronic products are broadly used in lives. How to make these products smaller and lighter is crucial to the success of these products. The demand of miniaturized mechanisms is gradually increasing. In all kinds of cameras, the focusing and zooming systems rely heavily on coil motors that move the lenses. However, the insufficiencies of coil motors have been an obstacle in the miniaturization of cameras. Therefore, it is a new application to use ultrasonic motors in focusing and zooming systems. The purpose of this research is to design a small-sized, light-weighted and mass-producible ultrasonic motor with low-cost operating equipments. This research uses bimorph as the main structure of Bimorph Ultrasonic Motor (BUSM) with alumina as contact point material and driven surface material which take advantage of the wear-resistant ability. The operating modes are simulated and verified with ANSYS. After measuring of the maximum velocity, the maximum mechanical load which can be endured by BUSM and the energy transducing efficiency, BUSM has proved it is a small-sized, light-weighted, simply-designed and mass-producible ultrasonic motor with simple operating equipments. The maximum size of the shape is only 9 mm * 3 mm * 2.3 mm, and the maximum driving velocity and output force is 255 mm/s and 20.8 g. The volume-standardized performances of BUSM are outstanding in comparison with other ultrasonic motors. In the future, we are confident that the application of BUSM will be broad.