The mechanism of screws consists of screws, nuts and frames. The main function is to change rotation to linear motion and transmit motion and energy at the same time. Depending on the friction properties of the twin screw, the screw mechanism can be divided into sliding screw mechanism and rolling screw mechanism. Type of type It can be divided into three types: power transmission spiral, conductivity spiral and adjustable spiral.The screw mechanism has the advantages of simple structure, practical production, stable transmission, no noise and easy self-locking.