A dustproof structure designed to protect the interior with high rigidity and small volume. coupling.Product composition diversification to achieve diversification of the combined form. High precision with pre - pressure mining angular bearing, high precision. Repositioning Accuracy:±0.02mm.Ball screw adopts grinding nut and shaft to achieve high precision and low noise. The internal ball circulation mode is adopted to increase the DN value and realize high-speed operation. High quality heat treatment technology. The coupling has high distortion rigidity and precise position control. Easy to assemble with motor. Low inertia ,suitable for small motor .The two ends of the synchronous wheel and belt are composed of two synchronous wheels and belt. In order to prevent the synchronous wheel from detaching and the belt tension is loose, a belt tension adjusting device is set.