ねじ本体とねじ山の弾性変形を考慮したボールねじの剛性 : 第4報, 予圧方式, 荷重条件の影響

抄録

The axial stiffness of a preloaded double nut is examined for preloading styles, preloading methods and various states of externally applied load. The axial stiffness under constant preloading (small value of spacing disc rigidity) separates into two groups following the direction of the external load regardless of other conditions. When the external load acts towards the preload relief, the stiffness decreases rapidly and the preload is lost just after the external force arrives at the preload value. Under the fixed position of preloading (large value of spacing disc rigidity), the stiffness varies following preloading conditions and external load positions. The maximum stiffness is obtained under the conditions of tension or compression in both the screw shaft and nuts, and the external force acts on the other side nut against the screw shaft on the supporting side. When the length of the screw shaft between double nuts becomes longer, the stiffness difference due to external load combination becomes larger as the spacing disc rigidity increases. The experimental values obtained under two representative external load conditions are slightly different from the calculated values, but their magnitude and behavior against the external load show a similar tendency.