Research On Dynamic Characteristics Of Gearbox Of Boom-type Roadheader's Cutting Unit

Boom-type roadheader is a set of machines that possesses the function of excavate, chip removal, automatically move,shoring and so on,which is main used to coal mining industry.Because of complicate and bad working environment and different nature of coal, the working equipments will lead to vibrate,which caused by internal and external incentives. As the gearbox of roadheader's cutting unit, if the frequency of internal incentive or external incentive is close to or matches the nature frequency of gearbox, It would happen resonance phenomenon, which will affect the stability and safety of the gearbox, in serious situation, it will led to the gearbox's parts damaged directly.This paper takes the gearbox of roadheader's cutting unit as the research object, and makes it overall dynamics research, which can not only ensure the roadheader working device work normally, but also can provide the basis for system analysis and design of gearbox of roadheader's cutting unit.At first,this paper summarized the roadheader's situation at present and developing direction at home and abroad. On the base of understanding roadheader's structure characteristics and the working principle,this paper had a systematic overview on the studying method of roadheader at home and abroad.Furthermore, gearbox's gears are parametric modeled by model software and assembled them to get secondary planet gears model,then import model into multi-body dynamics software by interface program of the modeling software and dynamics simulation software,apply constraint, drive and load to planet gear to realize dynamic simulation, we can get periodic force curve that is produced by gears mesh by simulation,which is the basis of the function analysis of the gearbox.What's more,establish the roadheader's gearbox model,Considering the accuracy and efficiency of analysis software, the gearbox is simplified reasonably and ignored little factors for the results, then import simplified gearbox model into finite element analysis software by the interface program of modeling software and finite element analysis software. Define unit types, mesh the modal and apply constraint, carry on the modal analysis to get natural frequency and corresponding vibration modal shape of gearbox first eight orders,and then describe it. In the end, find out the large deformation tendency of gearbox.At last, do harmonic analysis for gearbox based on the finite element analysis software.Then load the periodic force which is produced by the gears meshing on the surface between gears and gearbox, according to the modal analysis results,choose seven node of large deformation tendency of gearbox and certain its frequency-displacement curve, so we can judge the rationality of gearbox design. In addition, find weaknesses of gearbox strength, and propose suggestions for the design and optimization of the gearbox.This paper have a research on the dynamic characteristics of gearbox of roadheader's cutting unit,comprehensive using the technology of parameterized modeling by modeling software,simulation by dynamics simulation software,modal analysis and harmonic analysis by finite element analysis software,which is reference for the design and structure improvement of gearbox and improving vibration capability.