Compilation of drilling load spectrum based on the characteristics of drilling force

In order to overcome the problem that the existing methods of compiling load spectrum of spindle or machine tool mainly aim at the cutting force spectrum, torque spectrum and speed spectrum, respectively, which ignore the connection between each spectrum, in this paper, a method for compiling drilling load spectrum of motorized spindle in CNC machine tool based on the characteristics of drilling force is proposed. Firstly, drilling tests under different processing technologies are carried out to measure its load, and the correction coefficient in the empirical formula of drilling force is obtained through fitting the measured drilling force, which makes the calculation of the axial force and torque more reasonable. Secondly, compared with the extended factor method, the transcendental probability method is optimized to solve the ultimate load of the axial force. Then, after setting the axial force as the main load of drilling, an eight-stage load spectrum for the main load is compiled. Finally, according to the relationship between the axial force and other loads, the eight-stage loading spectrum is transformed into a multidimensional drilling load spectrum.