A METHOD TO DETERMINE GRINDING WHEEL PROFILES FOR MANUFACTURING THREADS IN PLANETARY ROLLER SCREW MECHANISM

In this paper, a method to determine the axial profiles of the grinding wheels for machining the screw, roller and nut in planetary roller screw mechanism is proposed. Firstly, the thread fillets of the screw, roller and nut are defined and there is a continuous first-order derivative at any point of the fillets. The equations of thread surfaces are derived. Secondly, the position relationship between grinding wheel and workpiece is described by using a coordinate transformation matrix. Thirdly, according to the theory of gear engagement, the equations of meshing for the grinding of the screw, roller and nut threads are developed. A parameterized program is designed by the meshing equations and the axial profiles of the grinding wheels are calculated: Finally, a specific example is provided and the influence of center distance and axis angle on the grinding wheel profiles is analyzed. The results show that the center distance has little influence of the grinding wheel profile.