Mechanical chuck is to provide a quick, accurate, simple, safe and effective connection device for the continuous action of the reel (inflatable shaft), to avoid the loosening or tightening of the reel in the process of operation, and to effectively improve the work efficiency and product quality. According to the installation method, the safety chuck can be divided into: shaft seat type and flange type. Widely used in: printing, packaging, plastics, paper, glass fiber, pharmaceutical, electronic batteries, textile and other machinery industries.