Study On Dynamic And Statics Characteristic & Its Experiment Of Hob Spindle System On Direct-drive Gear Hobbing Machine

Zero-transmission chain namely the direct drive which makes the length of main drive zero, reduces the number of crucial elements like high-precision gears and eliminates gears transmission error. It not only can increase the machine tool's machining precision and speed in a large scale, completely solves the attrition problem which exists in the mechanical transmission chain and maintains the tool's precision for a long time, but also can simplifies the tool's mechanical structure immensely and enhance its static and dynamic stiffness, this is in favor of realizing the designing and producing of reconfigurable manufacturing machine tools.The indies of direct-drive gear hobbing machine adopt electrical direct drive moment machine and hob indies adopt electrical indies structure, their rotate speed rates are controlled by electrical gears box, this increase its machining precision and speed. Based on researching the structure of direct-drive gear hobbing machine, this paper made research on hob indies yet electric indies' static and dynamic characteristics.The main content of this paper can be summarized as follows,①Introduced the research development of direct-drive gear hobbing machine, summarized the current situation of domestic and foreign research on the indies' static and dynamic characteristic, studied all the methods used in researching those characteristics and elaborated the meaning of studying this project and the main content of this paper. These provided a foundation to studying the two characteristics.②Discussed the main content of indies' static and dynamic characteristics and proposed requirements of analyzing the two characteristics according to the character of the indies structure.③Summarized FEM theory and its representative software PATRAN/NASTRAN and studied the two characteristics with the use of PATRAN/NASTRAN from designing angel. Those characteristics are closely related to the structural design parameter.④Studied the two characteristics from experimental angel. Static stiffness is the distortion under the cutting force of indies, this directly influences the machining precision. Dynamic stiffness is the indies' variation and natural frequency.⑤Studied the static and dynamic characteristics of the indies system, indicated both the static and dynamic processing characteristics are affected by the working and hob indies at the same time and proposed the method to enhance the two characteristics of the system.