Integrated system of digital coiling for spring

An integrated CAD/CAPP/CAM system of spring coiling is presented in this paper. In the CAD subsystem, four kinds of elementary shape feature are extracted based on feature and different spring shapes are described using these features. Then, the discretization method of spring solid surface is studied and a 3D modeling of spring is created. In the CAPP subsystem, an automatic generation method for CNC spring coiler setup is proposed using case- based reasoning (CBR). Through retrieving and modifying the past successful coiling case, the setup of the coiler for the new spring can be generate. In the CAM subsystem, the CNC instruction suited for spring coiler is designed and the NC program can be produced automatically according to the shape of the spring. At last, an example was given to illustrate the procedure of digital manufacturing for spring.