Study On Contact Analysis And Modification Of Gearbox Gearbox

In nowadays, the logistic is highly development. Because of its maneuverability, Forklifts have been widely used. Currently in the forklift, the gearboxes are mainly used. It has the characteristics of reliable operation and high transmission efficiency, but there are some questions that need to be improved. The first important problems are the vibration of transmission and noise. Moreover, when the manufacturing tolerance and assembly are not ideal, the gearbox has noise and the local tooth surface is failure too early. So in this paper, the contact analysis and modification of gears in the gearbox are researched to solve the problems above.In this article, the research object is a pair of cylindrical helical gears on a 3T forklift. At first, theprecision model is established and simplified using the involute equation in the SolidWorks software. Then we obtain the contact stresses contours and the displacement of the tooth top nodes through the static contact analysis by importing the model into the ANSYS software.This displacement is considered as the basis of the amount that need to be modified of the tooth profile. Then we analyze the principle of the gear modification, determine the calculation method of modification parameters and write the software to calculate the amount of modification on the VC++ platform according to the calculation formula. Finally, we model the shafts, gears and bearings of the gearbox in the RomaxDesigner and assemble them together. Then we apply the load according to the actual situation, make the simulation and analyze the effect of the modification. The results show that: through making the modification to the tooth profile, the transmission error is greatly reduced. And different conditions need different modification quantity. The long modification is better than the short modification.The parabolic modification is better than the straight line. For the tooth width direction modification, the partial load phenomenon is reduced. The drum center at the middle of the tooth width is not the best way, so we optimize the center of drum. We try to use the comprehensive modification method, the results are that the transmission error and tooth surface load distribution were both good.