"Mechanical Design" is a professional basic course for mechanical majors, which mainly describes the basic theory of mechanical design and the design methods of common mechanical parts. This book is divided into * * * chapters 15. The main contents are: introduction to mechanical design, screw connection and screw transmission, belt transmission, chain transmission, gear transmission, shafting parts and spring design, etc. 15 is an example analysis of mechanical design, with three cases as comprehensive reference. This book can be used as a teaching book for mechanical and near-mechanical majors of general application-oriented undergraduate students, and can also be used as a reference for engineers and technicians of related majors.