一般對於木材雕刻機較重視加工出來的工件外觀,較不要求精確的工件尺寸。而本研究主要是設計一台動柱式龍門雕刻機,所設計的主軸頭放置於橫樑中間,減少一般龍門型工具機C型結構所造成的彎矩問題,故設計時將注重於如何提高機台剛性避免主軸頭座自重下垂造成位移。此外,底座亦與一般市售工具機及雕刻機略顯不同,為天車式及動柱式工具機的改良型式。 雕刻機建模使用Solidworks 3D繪圖軟體繪製,並使用靜態分析以利隨時檢驗所設計的機台結構強度。為證明機械結構設計開發的可行性,以一台既有的雕刻機作為對照組,確認其可以完整雕刻出產品,以此結構進行自然頻率分析,並與本研究之機台互相比對自然頻率,從中判斷機台之結構剛性,由比對結果顯示所設計的雕刻機其自然頻率平均高於對照組34%以上,這意味著在相同加工條件下本研究的機台剛性更優於原有的雕刻機。
Generally speaking, a wood carving machine puts more emphasis on the appearance of machining workpieces, and the accurate dimensions of workpieces are not required. This study is mainly to design a double column carving machine, whose spindle head is placed in the middle of the beam to reduce the bending problem caused by the C-type structure of general machine tools. Therefore, it stresses on enhancing the rigidity of the machine to avoid displacement caused by the weight of the spindle head. In addition, the base of this machine is different from the general machine tools and carving machines. It is an improved form of the moving-bridge and moving-column type machine tool. This thesis designs the model of the carving machine by Solidworks graphics software, and also uses static analysis simultaneously to test the strength of the structure at any time while the designing stage. In order to prove the developed feasibility of the mechanical structure design, the study utilizes an existing carving machine as a control group which can completely carve out products. We can determine the rigidity of the machine structure through comparing the natural frequency analysis between the control group and the designed machine. The result shows that the average natural frequency analysis of the designed machine is 34% or higher than that of the control group, which means that the rigidity of the designed machine is better than that of the control group under the same processed conditions.