- 學位論文
使用田口式品質方法於光碟機噪音減低最佳化
OPTIMUM NOISE REDUCTION DESIGN OF CD-ROMS BY USING TAGUCHI’S METHODS
摘要
隨著資訊科技的發展，電腦所用之光碟機為了提高讀取的速度，已朝高轉速的方向發展。但是，伴隨而來即是較大的振動及噪音，尤其是噪音與使用者最有直接的關係，也是最為人所詬病的地方。因此，了解光碟機產生噪音之機制，進而降低光碟機的噪音實為一重要之工程課題。 光碟機的發展起始是CD-ROMs，再來是DVD-ROMs，以及現在最新的藍光DVD。而新技術的產生，目的在於增加儲存容量和存寫速度。而存寫速度的提升，除了有賴軟體及新技術的發展外，還有另外一個重要的機械零件，那就是主軸馬達，現在光碟機主軸馬達的轉速最高可以到達10,000 RPM左右，雖然說轉速可以更快，但是因為受到物理上的限制，可能會因為光碟片材質不良或是不平衡(例如貼標籤)的關係而使得光碟片在高速旋轉時會產生振動，因此可能會造成光碟片損毀。 光碟機高速運轉產生的噪音，有兩種。一個是因為主軸馬達帶動光碟片高速運轉，使得週遭的氣流跟著流動，光碟片受到週遭氣流而造成擺動的現象，而產生噪音，稱為空氣動力噪音。另一個是主軸馬達在高速轉動時，與光碟機產生的振動所引發的噪音，稱為結構振動噪音。本論文主要針對光碟機高速運轉時所產生之氣流與光碟機承載基座和上方機殼以及托盤之間的碰撞所引起的噪音來做改善。改善方法為使用不同種類的吸音棉，以及各種不同的黏貼位置再加上控制光碟片和拖盤之間的間隙，使得光碟機在高速運轉時其噪音值能夠有效的降低。 最後再使用田口式品質工程法搭配交互作用和商用軟體MINITAB的使用來求出其最佳化的解，將所算出的最佳化光碟機噪音減低數據和實際量測的實驗數據來做比較。
並列摘要
With development of information technology, high speed of CD-ROMs is manufactured. However, the issue of vibration and noise is focused with increase of the rotational speed. Therefore, to investigate the noise mechanism of CD-ROMs and to reduce the noise of CD-ROMs are important engineering issues. The optical storage device is changed dramatically: from CD-ROMs to DVD-ROMs and the latest blue DVDs with development of information industry. The new technology increases the storage capacity and read/write speed. The improvement of read/write speed not only depends on the new technologies and software, but also depends on the spindle motor, which is a key mechanical component. The rotation speed of spindle motor is limited to the maximum speed of 10,000RPM because high rotation speed may causes damage of CDs. There are two sources of the noises resulting from the CD-ROMs spinning at a high speed. The first source is the aerodynamic noise of the vibration of the disc due to the airflows of the high-speed spinning disc. The second source is the structural noise of the axle motor of the CD-ROMs vibrating with the joint base. In order to reduce noise, the choice and location of absorption materials, and the gap between CDs and plates are considered in this research. Besides, Taghchi methods and MINITAB are used to identify the optimal designs, and the comparison between calculations and experiments is mentioned in this research.