工具機進給系統幾何誤差量測技術之研發

Development of a Geometric Errors Measurement System about Feed Drive System in Machine Tool

吳柏震(PO-CHEN WU)

指導教授 ： 鄭志鈞

國立中正大學/工學院/機械工程學系/碩士(2016年)

摘要

本研究為研發一套量測快速且架設方便的平行度與直線度量測系統，能方便於組裝與校正線性滑軌，由於傳統上多量測使用千分錶，但其準確性不高，而光學量測其儀器價格昂貴且架設麻煩。
工具機加工過程中是依靠線性滑軌帶動上方工作平台使其線性運動，因此本研究運用相對向量的概念發展單線軌直度量測理論與相對平行度量測理論，以及應用兩點連續法取得工作平台移動偏移量，據此發展一套量測系統，分別針對工作平台組裝前後的線軌狀況進行量測。在無法利用馬達編碼器取得線軌位置訊號時，本研究發展一智能化滑塊，利用紅外線感測器偵測螺絲鎖孔判斷滑塊於線軌上的位置。本實驗使用接觸式位移感測器量測線軌狀況，其優點為量測準確度高且不容易受環境因素干擾，而使用3D印表機印製夾持位移感測器之夾具，其優點為能快速改善夾具設計，縮短製造夾具過程中加工所需耗費的時間。而本研究中的量測結果皆使用光學式量測(雷射干涉儀)以比較其準確度，使本量測系統較具可靠度。透過本量測系統量測線軌狀況，可幫助調整及組裝線軌，提升整體加工精度。

關鍵字

線性滑軌 ； 相對平行度 ； 相對直線度 ； 位移感測器

並列摘要

A novel system used to measure simultaneously the relative parallelism and the straightness of linear guideways is developed. The objective of this measurement system is to provide an efficient, user-friendly and accurate measurements. The system consists of four LVDT displacement sensors installed on the LGT carriages. The relative vector method is adopted to calculate the linear guideway straightness both in the horizontal and vertical planes. Moreover, a novel LGT carriage integrated with infrared sensors is developed, which provides the positioning information of carriage on the linear guideway. With this novel carriage, the linear guideway straightness versus position can be determined when the engineer corrects the linear guideway manually. Furthermore, the measurements of linear guideways can be conducted before and after the worktable installed on feed drive system. Therefore, the worktable influence on the linear guideways straightness can be quantified, which provide an assessment of the stress of the LGT carriages. The measurements performed on the linear guideway using the proposed system are compared with those using the laser interferometer. Results show that the differences in measuring the straightness of reference and driven guideways between the proposed LVDT system and laser interferometer are less than 1μm and 9μm, respectively. The difference in measuring the relative parallelism between the reference and driven guideways are less than 1μm and 7μm on the horizontal and vertical planes, respectively. This system also provides the straightness information of the moving worktable. The accuracy of this proposed measurement system requires more improvement; however, it provides a more efficient and reliable measurements than the traditional method of using micrometers.

並列關鍵字

linear guideway ； relative parallelism ； relative straightness ； displacement sensor

參考文獻

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