Dong Sihui, Li Shiqun, Fu Shenghui, Wang Kang
School of Traffic and Transportation Engineering, Dalian Jiaotong University, Dalian, 116028, China.
School of Mechanical and Electronic Engineering, Shandong Agricultural University, Tai'an, 271000, China.
Sci Rep. 2022 Oct 17;12(1):17386. doi: 10.1038/s41598-022-22342-6.
As the main component of the tractor gearbox, the box has the functions of shifting operation and carrying the cab, it also carries part of the framework function. If the strength, stiffness, or vibration characteristics of the box do not meet the allowable requirements, large vibration and noise may occur, and even there is the possibility of fracture in some limiting conditions. To solve this problem, according to the structural parameters of a gearbox, the three-dimensional model of the box was established by using the three-dimensional modeling software Creo. According to the dangerous degree of the transmission load when the tractor is working normally, three vehicle working conditions are selected: a round of suspension conditions, farm tool lifting conditions, and emergency turning conditions. In addition, according to the transmission ratio of each gear meshing inside the gearbox, two gear conditions are selected: gear condition one and reverse gear condition one. The forces of the box under these extreme conditions are analyzed. The static analysis and modal analysis of the tractor gearbox are carried out by using the Static Structural module of ANSYS Workbanch. The deformation, equivalent stress distribution, and modal vibration frequency of the gearbox are tested. The topology optimization method is used to improve structural defects and reduce box quality. The results show that the weight of the optimized box reduces by 8.44%, the deformation decreased by 15.89%, and the equivalent stress decreased by 18.34%. The strength and stiffness of the box are improved, the quality is lightweight, the waste of resources is reduced, and the heat dissipation performance and fracture resistance of the box are enhanced.
作为拖拉机变速箱的主要部件，箱体具有换挡操作和承载驾驶室的功能，还承担部分框架功能。如果箱体的强度、刚度或振动特性不符合允许要求，可能会出现较大振动和噪声，甚至在某些极限情况下存在断裂的可能性。为解决此问题，根据某变速箱的结构参数，利用三维建模软件Creo建立了箱体的三维模型。根据拖拉机正常工作时传动载荷的危险程度，选取了三种车辆工况：一轮悬挂工况、农具提升工况和紧急转向工况。此外，根据变速箱内部各齿轮啮合的传动比，选取了两种齿轮工况：一档工况和倒一档工况。分析了箱体在这些极端工况下的受力情况。利用ANSYS Workbench的Static Structural模块对拖拉机变速箱进行了静力分析和模态分析。测试了变速箱的变形、等效应力分布和模态振动频率。采用拓扑优化方法改善结构缺陷并减轻箱体质量。结果表明，优化后箱体重量减轻了8.44%，变形量减小了15.89%，等效应力减小了18.34%。箱体的强度和刚度得到提高，质量轻量化，减少了资源浪费，增强了箱体的散热性能和抗断裂能力。
