本文以B-Spline曲線建立螺旋形彈簧模型，利用其具有局部控制及微分連續性等性質，即可有效地建立所需之彈簧並進行應力分析。本文以酒桶形彈簧為例子，使用ANSYS有限元素分析軟體模擬彈簧靜態壓縮情形，並進一步探討力-位移曲線、等效應力及剪應力分佈等結果。
酒桶形彈簧受到壓縮時，可以觀察到內側之等效應力大於外側的現象，且因兩端直徑變化不同造成上下端之等效應力也有所差異，而剪應力之分佈也是這種情形。接著本文利用控制點變更彈簧之幾何形狀，以觀察各參數變化下對力-位移曲線造成的影響。線徑越粗，會使彈簧常數K值越大。而改變底徑需考慮與下一圈接觸之情形，底徑越大，滑動量相對較少，反作用力隨之增加。改變中間部分之節距則是影響接近壓實的接觸狀態。

By using the B-Spline curve, the spring models have been built in this thesis. Since the B-Spline curve has the properties of local control and differential continuity, it is used to create the finite element model in stress analysis. The ANSYS program was used to simulate the barrel-shaped spring due to static load. The force-displacement curve, equivalent stresses and shear stress distribution are shown in the result.
In the compression process of barrel-shaped spring, the inner equivalent stress is greater than outer, and the equivalent stresses of the top end and bottom end varied with different spring diameters. Distribution of shear stress is similar to the distribution of equivalent stress. By using the control points to change the geometry of spring, the performance of spring in force-displacement curve with varied parameters can be observed. The results show that the bigger the coil diameter, the greater the spring constant. The condition of contact between circuits should be considered in varied base diameters. The bigger base diameter, the less sliding distance, and the reaction force increased. Changing the spring pitch in the middle part will affect the contact condition that the spring is mostly compressed.

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