Abstract: Stable enough wire driving force is the key to improve the forming quality.Not only to control the size of driving force,but also to ensure the stability of the extrusion filament process,the influencing factors of friction driving force analyzed.And the calculation formula of friction driving force can be derived by theoretical analysis.Wire feeder is the key to design the spray head system.According to the analyzed influence rule of the driving force,a kind of opening remote wire feeder is designed.It can provide large enough friction driving force to ensure wire feeding smooth,and has important practical reference value.

Key words: Fused Deposition Modeling(FDM), wire feeder, structure design, driving force