Research on Meshing Curve of Double-circular-arc and Non-circular Gear Motor of Roof Bolter for Small-face TBM Support.

When the TBM with a small face and a small turnin gradius works in rock fragmentation geology, it requires support by the bolt to ensure the safety of operation. The hydraulic motors used in the existing roof bolters are piston or planetary rotor cycloid motors, which have the shortcomings of large structural dimensions and weights, while non-circular gear motors, with the characteristics of compact structure, high power-to-weight ratio and strong pollution resistance, have obvious advantages in the construction of small-face tunnel boring. The working principle and composition of a 4-6 non-circular gear motor with variable center distance are introduced, and in view of the difficulty in designing the high-order elliptic pitch curve and tooth profile of the non-circular gear motor, it is proposed to adopt the double-circular-arc pitch curve, use nonlinear objective programming method to establish the nonlinear constraint equation, and then solve the optimal value through Matlab to determine the parameters of the sun gear and inner ring pitch curves of the double-circular-arc and noncircular gear motor and to further design the sun gear and inner ring tooth profiles. This method simplifies the design of noncircular gear motors, which can provide a design reference for the development of roof bolters for small-face TBM support. [ABSTRACT FROM AUTHOR]