Study On The Rotary Drilling Mechanism With Ultrosonic And Low Frequency Vibration

In the anti-hijacking rescue and national defense security,in order to carry out real-time monitoring of criminals,a kind of equipment which can drill holes on the wall secretly with high efficiency and low noise is urgently needed.The high noise of the drilling equipment,such as the electric drill,also seriously affects the normal life of the residents during the decoration.Therefore,with the aid of special funds,we developed a high and low frequency compound vibration drilling equipment and conducted preliminary research.The main contents of paper are as follows:1.Based on the mechanism of vibration drilling,the high and low frequency compound vibration drilling equipment was designed by adding a low-frequency vibration along the drilling direction on the existing rotary ultrasonic drilling equipment,which laid a foundation for the dynamic analysis and experimental study.2.To explore the main performance parameters of equipment,we had vibration tests of the equipment.By simplifying the model of the equipment,we studied the dynamic characteristics of the system.The dynamic analysis and simulation analysis of ADAMS were carried out,which provide a theoretical support for the construction and experimental research of the experimental platform.3.The drilling experiments were carried out with clay bricks as experimental materials under different conditions.Firstly,we studied the effect of various excited frequency,tool speed and static-pressure on the drilling efficiency,which showed that the drilling efficiency is increased with the excited frequency and speed of the drilling tool,and the best static pressure value is existing.Secondly,through the collection and analysis of noise under different conditions,we explored the levels and sources.Finally,through analysing the particle size distribution of cuttings and the vibration signal of tool side and workpiece side,we drawn the working mechanism of the compound vibration drilling.Ultrasonic vibration is mainly responsible for the hammer effect of brittle material,which is broken into particles;and the low frequency vibration is mainly responsible for the speedy transportation of broken particles.It is proved that the principle of the high and low frequency compound vibration drilling is applicable for the low noise drilling through the above experiments.