相較於直傘齒輪，螺旋傘齒輪在嚙合過程中因有較高的接觸率以及較長的接觸斑，所以齒面所受負荷較小，承載能力較佳。傳統的螺旋傘齒輪製造，多以專用加工機或多軸CNC加工機加工，除加工成本較高外，齒輪齒面設計也複雜，而粉末冶金製造之螺旋傘齒輪，則可以大量生產而降低成本。 因此本論文針對粉末冶金螺旋傘齒輪，建立適當之齒面修整，並以有限元素法進行接觸分析以及建立測試設備完成驗證測試，以驗證前人所發展之修整型螺旋傘齒輪對受載齒面接觸分析模型之正確性。本研究所使用之螺旋傘齒輪齒面係以球面漸開線齒廓沿齒輪軸線以等角度旋轉方式產生，以利脫模。而為降低誤差對傳動造成之敏感性，論文中提出對數曲線之齒線修整與拋物線之齒形修整的雙隆起修整齒面。並以此齒面以所發展之受載齒面接觸數值分析程式與有限元素分析軟體，分析齒輪對在理想組裝與具有組裝誤差下之齒對嚙合及受載齒面接觸應力。以驗證齒面修整設計與誤差對於齒對嚙合情形之影響。 由數值分析結果可得知齒面修整設計可避免齒對嚙合時常見在齒面邊緣發生應力集中的問題。而各種組裝誤差對接觸點路徑與傳動誤差影響不大。而有限元素分析結果顯示，齒輪對在理想與具組裝誤差情形下所得到各接觸斑位置、形狀及大小與所發展的受載齒面接觸數值分析程式分析結果相近，可驗證數值分析程式之可信度。 在本研究中，亦完成對應之模具設計，並製作出粉末冶金齒輪成品，並透過所設計、製作之相關驗證測試治具，驗證數值分析結果正確性及本研究設計之齒輪對可用性。 ;Compared with the straight bevel gears, helical bevel gears perform a greater load capacity due to higher contact ratio and longer contact patterns during gear meshing. The traditional manufacturing of helical bevel gears are mostly processed on gear cutting machines and multi-axis CNC machines. In addition to higher production costs, designing gear tooth surface is also complicated. However, the helical bevel gears manufactured by powder metallurgy methods can be mass produced and the cost reduced accordingly. Therefore, the aim of this thesis is to construct appropriate tooth surface modification for powder metallurgy helical bevel gears, and to carry out the contact analysis by using the finite element method and to establish the test equipment to complete the validation test so that the correctness of the developed LTCA model for modified helical bevel gears can be verified. In order to smoothly demold, the helical bevel gear tooth surface used in this study is generated by the spherical involute tooth profile with a constant rotational angle along the axis of the gear. In order to reduce the sensitivity of the errors to the transmission, a double-crowning is proposed in the thesis. Furthermore, the tooth contact stress of the gear pairs with and without assembly errors are analyzed by the developed loaded tooth contact numerical analysis program and the finite element analysis software, so as to validate the effect of the flank modification and the assembly errors on the contact characteristics. The results from numerical analysis show that the flank modification on the helical bevel gears avoids the concentrated contact stress on the edge of the tooth surface. The various assembly errors have little effect on the contact point paths and the transmission errors. On the other hand, the results from the finite element analysis show that the position, shape, and size of each contact patterns of the gear pair with and without assembly errors are similar to the results of the numerical analysis. This can verify the feasibility of the developed numerical analysis program. In this study, powder metallurgy helical bevel gears are manufactured by the molds that are also designed in the study. The tests of these gears on the designed and produced test fixtures validate the correctness of the numerical analysis results and the feasibility of the modified helical bevel gear pair which is designed in this study.
