Abstract： Longitude-bend elliptical vibration assisted drilling has significant advantages in reducing the cutting force and cutting heat of deep cavity machining and reducing the friction between the tool and the hole wall compared to other vibration forms. At present, in the design of the longitude-bend elliptical vibration assisted drilling device, due to the installation of the appurtenances such as the drilling tools, etc, the actual frequency and the design frequency of the longitude-bend elliptical vibration assisted drilling device are greatly different. At the same time, the longitudinal vibration and the bending vibration cannot obtain the same frequency resonance mode. For this reason, this paper studies the design and optimization methods of the longitude-bend elliptical vibration assisted drilling device. Firstly, according to the elliptical trajectory output requirements, the overall structural design of the longitude-bend device is carried out. Analytical method is used to design ultrasonic transducer and horn, and the initial three-dimensional model of longitude-bend elliptical vibration assisted drilling device is established. Establishing the kinematics modeling of longitude-bend elliptical vibration on the basis of the established three-dimensional model; Secondly, based on the principle that the longitude-bend resonant frequency is close to the target frequency, the influence of the tool and ER collet nut on the resonant frequency is reduced by equal mass method and simplified method, and the finite element analysis software ANSYS Workbench is used to control the variable. The method optimizes the longitude-bend elliptical vibration assisted drilling device; Finally, the structure size is determined according to the finite element optimization results, and the dynamic characteristics are analyzed. It is verified that the design and optimization method of the longitude-bend elliptical vibration assisted drilling device proposed in this paper can reduce the influence on the frequency of appurtenances such as the drilling tools, etc, the same resonant frequency of the longitude-bend elliptical vibration assisted drilling device is achieved
2020, 
