Using the tooth ratchet mechanism using in all kinds of machine as an example

a mathematical model for parametric design about ratchet mechanism is established.The parametric design is realized by using second developing technology for AutoCAD in VB.When the design parameter in the system is selected

the relating parameter can be calculated and the design results can be checked automatically

the ratchet mechanism engineering drawing can be given out automatically

label dimension and technology terms can be marked

the efficiency is improved.A theoretical basis of digital design and manufacture for ratchet mechanism is provided.