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最优化设计的安全销,一方面要求它能在运行中长期承受一定范围内的负荷,另一方面当负荷超过上限时它就必须及时断裂。对这种优化设计的安全销而言,在试验台上测定的静载断裂力矩和疲劳负荷力矩的差值就达到了最小值。通过在联轴节试验台上进行的试验,在销子底槽部分测量的应变和用有限元法计算的结果证实:安全销的槽口断面部分承受纯剪切应力。槽口不但一方面引起静载断裂强度的提高,而且另一方面在承受疲劳应力的情况下又使可承受的力矩大大降低。由一个大的内孔和一个薄的剩余横断面使所介绍的最优化销子的几何形状达到很小的应力集中系数。静载断裂力矩和动载疲劳断裂时的力矩之比可减小到1.9。
The optimally designed safety pin, on the one hand, requires it to withstand a long-term load in operation over a long period of time, on the other hand it must be broken in time when the load exceeds the upper limit. For such optimized design safety pins, the difference between the static load breaking moment and the fatigue load moment measured on the test stand reaches a minimum value. Through the test on the coupling test bench, the strain measured at the bottom of the dowel pin and the results calculated by the finite element method confirm that the notched section of the safety pin is partially subjected to the pure shear stress. Notch not only caused on the one hand increase the static load breaking strength, but on the other hand in the case of fatigue stress, but also make the bearing torque can be greatly reduced. The geometry of the optimized pin is achieved with a small stress concentration factor by a large bore and a thin residual cross section. The ratio of moment at break to moment at break and dynamic fatigue can be reduced to 1.9.