Study on jamming mechanism of the planetary roller screw mechanism

This paper explores if there exists jamming phenomena in the planetary roller screw mechanism. Three kinds of jamming phenomena, such as mechanical jamming, dead point jamming, and self-locking jamming, are elaborated by using static analysis of the planetary roller screw mechanism. The results show that mechanical jamming and dead point jamming won't happen in the planetary roller screw mechanism under the condition of high strength materials, high post-treatment hardness and without regard to error. And when the nut bears unbalanced loads or when the nut and the roller may self-lock in small pitch, the variation of input torque and output velocity is analysed by dynamics simulations. The fact that the planetary roller screw mechanism will not be self-locking jamming is verified.