Modeling And Optimization For Impact Performance Of An Electrically Driven Impact Pneumatic Hammer

Electric hammer is a kind of power tool which is widely used,and it also belongs to impact machines.Currently,R&D engineers in domestic electric hammer manufacturer lack of understanding for design theory in the process of R&D,which lead to low efficiency.Therefore,the simulation model is established according to the mathematical model,and the analysis and optimization is conducted by means of combination test and optimization design,which provide guidance for the process of R&D of electric hammer.And there are five chapters in this paper:In the first chapter,the domestic and foreign development situation is summarized,and the necessity of this study is analysed.Then the researching theories and methods are determined by referring to the methodology proposed by former researchers.In the second chapter,the simulation model of the driving mechanism is implemented according to the gas polytropic equation.After that,the influence on the performance of the electric hammer is analysed for the following parameters:diameter of the cylinder,frequency,initial position and mass of the impact piston,length of the crank,diameter and position of the gas compensating hole.Lastly,a combination experiment is conducted in order to verify the correction of the simulation model.In the third chapter,the simulation model of the impact mechanism is implemented according to the stress wave propagation methodology.Then the structure parameter of the anvil is analysed by means of combination test.In the end,the FEM is used to simulate the process of percussive drilling and breaking in order to validate the reliability of the simulation model.In the fourth chapter,the simulation code of the whole impact system is written by combining the two models established in the second and third chapter.Based on the simulation code,the system is optimized by optimizing the configuration of the structure parameters in order to maximize the penetration depth during a single process of impact.And different work conditions is also well considered.The fifth chapter is the summary and prospect of this study,which gives some suggestions on further research.