Development of a form milling method for line gear: principle, CNC machine, cutter, and testing

Milling, as one of the most versatile machining methods, which is simple and flexible, is suitable for small and medium batch production of gears. Relevant method of form milling for line gear, a new type of gear, was studied in this paper. Firstly, the principle of a form milling for line gear was presented, that is capable of machining line gears with circular helix, conic helix, or planar helix as their contact curve, and of external or internal line gears. Secondly, the corresponding design methods of form milling cutters were proposed on basis of the structural characteristics of external and internal line gears, separately. Then, on the basis of the milling characteristics of line gear, a special CNC machine tool was developed, which is much cheaper than a five-axis machine tool. Finally, through the relative experiments on line gears and line gear reducers, the feasibility of the processing method proposed and the practicability of the special machine tool developed were verified.