Control Method and Device for Cutter Shaped by Helical Spring

Disclosed are a control method and a device for a cutter shaped by a helical spring, which comprises two cutter position controlling devices (20) connected to two spring outer diameter cutters (10) respectively and comprises a cutter lifting device (30). The two cutter position controlling devices (20) are arranged in the same mounting plane (40). The cutter position-controlling device (20) controls an amount of displacement of the stretching and retracting of the two spring outer diameter cutters (10). The amount of displacement of the spring outer diameter cutters (10) and the amount of up and down movement of the mounting plane (40) are controlled simultaneously by a motor (50). By applying the concept of relative coordinates, the requirements of control can be simplified from two two-dimensional control movements to three single-axis linear movements by using the centre (P3) of a spring coil as the origin of the coordinates for the movement of the spring outer diameter cutter. In the case that the distances of linear movement on the three axes are identical or at a fixed ratio, the advantage of reducing the number of motors is achieved.