本論文之目的為研究押出機減速機箱體系列化發展模式，用以簡化產品開發流程、節省設計時間。根據此一模式，將可在不變更基本設計的條件下，使每一型箱體的強度或剛性保持相同的水準，以承受隨尺寸變化而增加的押出機推力。 在本研究中將押出機減速機分為小型及大型兩類，分別設計基本箱體以及建立3D模型，並定義箱體各尺寸參數名稱。而後依據相似性理論，以基本箱體為基礎發展系列箱體，經由有限元素分析之結果，確認系列箱體之發展是否符合相似性理論。 箱體分別根據應力相等或變形量相等的條件發展系列化尺寸。有限元素分析結果顯示，在等應力發展模式下，系列之各型箱體最大應力值極為接近；而在等變形發展模式下，系列之各型箱體最大變形量亦極為接近，此結果可證明相似性理論在系列化發展上的實用性。 The aim of the thesis is to study the appropriate approach for developing the size ranges of the housing of the single-screw extruder drives, whereby two conditions are considered: the strength and the stiffness of the developed housings will remain the same correspondingly, namely “strength invariant” and “stiffness invariant” condition. By applying this approach the development of the gearbox housings can be simplified and the development time can be also reduced. In the research the extruder drives are divided into two basic types: the small series and the large series. The basic design of the housing series is at first constructed as a parameterized 3D-CAD model for each type. The size ranges of the each housing types are developed with aid of the similarity laws under the condition “strength invariant” and “stiffness invariant” respectively. Finally the stress and the deflection of the developed housings, according to the corresponding condition, are analyzed through the FEM. The FEA results show that the maximum principal stresses of the developed housings according to the “strength invariant” condition remain very close. The similar results are also found in the housing developed according to the “stiffness invariant” condition. From the results we can conclude that the similarity law is suitable for developing size ranges of the products.