Research on digital design method of worm helicoidal surface

With the requirement of high quality, precision and reliability of worm driving device, it is difficult to fulfil these demands by traditional design method based on formula derivation. Digital technology is a viable means to resolve this problem. In this paper digital expression means of helicoidal surface is presented. Based on research the method to obtain digital helicoidal surface by each kind of generating curve, a new way using straight line as generating curve to design three ordinary helicoidal surface named Archimedes´ helicoidal surface, straight sided normal helicoidal surface and involute screw surface is put forward.