有限要素法によるテーパーコイルばねの剛性設計

抄録

A tapered coil spring is the one whose wire diameter isn't constant and continuously changes. The spring possesses the non-linear stiffness which increases with increasing the load applied. Although its application is the axle spring for railway car because of passively changing the stiffness under the applied load that relates the number of passengers, making formula is difficult due to the gradually diameter change of tapered wires. Finite element method has often been applied to the analysis of mechanics for the springs and it should be found the appropriate end turn shape of the springs for real deformation of the coil and we found the optimized end turn for constant deformation. The stiffness of the spring follows the approximate formula on each region in different diameter before contact between wires and the formula on the region of thick wire after contact. The stiffness of the spring actually could be determined for varying the pitch and predicted using finite element method.