奈米潤滑脂應用於氣壓缸之動態磨擦特性量測

Dynamic friction behaviors of the grease with nano-particles as additives in pneumatic cylinders

藍冑偉(Chou-Wei Lan)

指導教授 ： 張合

國立臺北科技大學/機電學院/機電科技研究所/博士(2012年)

摘要

本研究為準確測量並分析氣壓缸的摩擦力及運動特性，建立了一個新型的氣壓缸摩擦力量測系統，利用此量測系統同時探討奈米顆粒添加入潤滑脂中對氣壓缸磨擦特性產生之影響及不同重量百分比之奈米潤滑脂對於氣壓缸之stick-slip motion是否有明顯之改善效果。氣壓缸的運動動態特性主要是受到氣壓缸內部油封、潤滑脂及氣缸內部表面及磨擦特性所影響。實驗中，氣壓缸將在不同的潤滑及操作條件下，進行摩擦力量測，了解氣壓缸在無潤滑、一般潤滑脂及奈米潤滑脂條件下，其運動動態特性有何差異性，並藉此探討影響氣壓缸運動動態特性之因素。本研究之氣壓磨擦力量測平台是利用一具氣壓缸提供穩定之力量輸出驅動待測氣壓缸，並安裝一具S型荷重元量測待測氣壓缸內部油封與氣壓缸壁之間相互運動所產生磨擦力。此量測系統並使用兩組氣壓壓力感測器監控氣壓缸在作動期間，驅動缸體內的氣壓壓力變化以確保驅動力穩定輸出。速度控制係由一具拉線式編碼器進行速度的量測，並透過LabView程式進行監控，此系統所有量測數據皆利用LabView程式進行資料收集及壓力速度控制。
此篇論文同時探討油封及潤滑脂對於氣壓缸摩擦特性所產生的影響，利用TiO2及CuO奈米顆粒進行潤滑脂之性質改良，將奈米顆粒作為潤滑脂之添加劑，分析奈米顆粒對於潤滑脂之改質效應，並分析奈米潤滑脂對於氣壓缸摩擦特性之影響，分析應用不同重量百分比之奈米潤滑脂進行氣壓缸磨潤時，氣壓缸運動動態特性分析。同時，兩組不同之油封進行磨擦特性量測，挑選表現較佳之選項進行奈米潤滑脂之磨擦特性分析。結果顯示，奈米顆粒添加入潤滑脂可顯著降低磨擦物體之磨耗及所產生之摩擦力。對於氣壓缸運動動態特性而言，奈米潤滑脂可改善氣壓缸運動之Stick-slip motion，其中以CuO奈米顆粒之改善效果較佳。本論文為改善氣壓缸之運動動態特性並分析奈米潤滑脂應用於氣壓缸之磨潤的磨潤特性，設計製作了兩套量測平台。此兩組測試平台將可提供氣壓系統及潤滑工程之研發工程師一套完整且妥善之測試系統，可加速並準確提供設計時所需之數據。

關鍵字

氣壓缸 ； 摩擦特性 ； 奈米顆粒 ； 潤滑脂

並列摘要

This study aims to build new friction force test equipment to measure and analyze the frictional force between seal and cylinder bore and dynamic friction characteristic of pneumatic cylinder with nano-lubricant. The dynamic characteristics of pneumatic cylinder are affected by guide seal, piston seal, grease and surface of cylinder bore. In seeking to improve the friction force characteristics of pneumatic cylinders and to clarify the friction phenomenon of the pneumatic cylinders, this study describes friction force measurement tests to measure the friction force of pneumatic cylinder, under both dry and lubricated conditions. Experimental equipments are designed to assess the effect of seals and lubrications in pneumatic cylinder, where the velocity and pressure of the driving cylinder are controlled. Measurements of friction force are shown for velocities of up to 200 mm/s.
In this research, the first step, TiO2 and CuO nano-particles were chose to synthesize the nano-lubricants. Secord, a ball on flat test equipment was employed to measure the lubrication properties of Nano-lubricants. And the friction force measurement of pneumatic cylinder was used to measure the friction force of pneumatic cylinder with different seals in dry and lubricating condition. In these experiments, the best nano-lubricant and seal were chosen into analyze the friction characteristics of the grease with nano-particles as additives in pneumatic cylinder.
The results appear that the friction force measurement system can effectively and precisely measure the friction force between seal and cylinder bore. And, in low velocity operate condition; the ball effect of the nano-particles can avoid the stick-slip motion of the piston. In the high velocity operate condition; the nano-particle can reduce the damp of the lubricant so that the friction force is not getting to increase. This study develops two equipments to measure and analyze the lubrication properties of the nano-lubricant and the dynamic characteristic of pneumatic cylinder with nano-lubricant. These equipments can help the researchers, engineers and designers to study any kind of lubricant and different setup of seals in the pneumatic cylinder.

並列關鍵字

Pneumatic cylinder ； Friction characteristic ； Nano-particle ； Grease

參考文獻

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