薄膜式節流器參數分析與設計

Analysis on Parameters and Design of Membrane-type Restrictors

張庭瑜(Chang, Ting Yu)

指導教授 ： 林士傑

國立清華大學/工學院/動力機械工程學系/碩士(2015年)

摘要

為了因應超精密機械產業與高承載的需要，許多工具機台採用液靜壓軸承做為設計，其中系統需要節流器做為壓力補償元件。節流器的形式會影響軸承表現，而主動式節流器會比固定式節流器有更佳的剛性表現，又以薄膜式節流器在製造上的穩定性較高。故本文將分析薄膜式節流器的設計，取代一般常見的毛細管與孔口節流器。
有關薄膜式節流器性能的模擬，過去許多研究將薄膜變形簡化，與實際節流器流阻仍有不少差異。因此本研究將針對薄膜式節流器進行分析，藉由電腦程式的數值模擬，加入薄膜變形計算，來幫助了解薄膜式節流器相關參數的影響，包含薄膜材料、組裝間隙、尺寸幾何對節流器流阻的影響。並且以理論公式與模擬程式為根據，配合不同的單向墊軸承評估最佳的薄膜式節流器參數，藉以建立單向墊軸承選配薄膜式節流器時的流程與指標。
本研究亦在設計上加入考慮薄膜的疲勞破壞與節流器加工情形，利用彈簧預壓對膜片的變形量進行調節，並模擬其性能表現。最後進行實驗量測，與模擬結果進行比對，來驗證所建立的理論模型。

關鍵字

液靜壓軸承 ； 薄膜式節流器 ； 流阻

並列摘要

In order to achieve high precision machining, hydrostatic bearing are frequently adopted in many machine tools design. Restrictor which can compensate pressure plays an important role in the hydrostatic bearing system. The performance of the hydrostatic bearing is highly dependent on the design of restrictors. The design of membrane-type restrictor, one of the self-compensation restrictors which can provide higher bearing stiffness than passive restrictors is studied.
In this study, it is of interest to study effects of parameters on the performance of the bearing system. And such that a proper way to design restrictors for associated bearing system can be identified. The parameters studied include materials of the membrane, restrictor clearance and the geometry of the restrictor.
Based on the theory and simulation program, the effects of parameters on bearing performance can be studied and then the optimal parameters of the membrane-type restrictor can be identified for a desired single pad bearing.
Concerning about the endurance failure of the membrane and the manufacturing imperfect of the restrictor, a spring is adopted to adjust the deformation of the membrane by preloading. The performance of the spring-membrane-type restrictor is also be simulated.
A test bench of membrane-type restrictor is designed to verify the simulation result. These results provide a formulation for the design of membrane-type restrictor.

並列關鍵字

hydrostatic bearing ； membrane-type restrictor ； flow resistance

參考文獻

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