A new approach to generating trochoidal tool paths for effective corner machining

In conventional corner machining, the cutter machines the workpiece in a large engagement angle which could even be π. More cutting edges are engaged at each cutting moment; thus, the cutting force is great, and the un-cutting time of each cutting edge is less for the cutter releasing heat; thus, the cutting temperature is high. It is common that the cutter in corner machining often wears out quickly and the tooling cost is high. Recently, the trochoidal tool path has been recognized in industry; however, due to no well-established trochoidal tool path generation method, this path is not widely used yet. In this paper, a new approach to generating trochoidal tool path is proposed. First, the trochoidal tool path is represented with two parameters. The material removal rate and the cutting force in trochoidal machining are formulated. Then, an optimization model of the tool path that is established to achieve the machining time is the shortest while the cutting force is expected. Relationships of the trochoidal tool path with the material removal rate and cutting force are analyzed, and a method of choosing the optimal trochoidal parameters is proposed. Finally, a practical example is rendered and the results demonstrate validity of this proposed method.