基于强度比较的微耕机刀轴的优化设计

摘要

Rotary tiller is an approved product with long-term performance and reasonable design.Taking the rotary tiller blade of ISG9-50 as the intensity benchmark,the design of the original blade has been improved,based on the stress analysis and comparison of the benchmark and original tiller blades.The study can provide a new method for rationally using material,cutting product cost and optimizing machinery structure.The tiller blade has been improved from the original Φ19-diameter solid shaft to the 20 mm × 8 mm × 6 mm(external diameter × inner diameter × thickness) hollow shaft,with material consumption reducing 7％ and maximum equivalent stress of 55.808 MPa lowering 8.3 ％,less than the 56.818 MPa of the rotary tiller.The improved blade has the maximum deformation of 0.020 2 mm,less than the original 0.020 6 mm and the benchmark 0.029 34 mm.This result indicates that the newly-designed components and the benchmark products have the same intensity reliability if they have the same stress and strain.The improved tiller blade would have more scientific stress,structure and size.%选择型号为ISG9-50的旋耕机刀轴作为强度基准,在对基准刀轴和原设计的微耕机刀轴进行应力分析和比较的基础上,对原微耕机刀轴进行了改进设计,该研究为合理利用材料,降低产品成本,尤其为机械结构的优化设计提供了一种新方法.改进的微耕机刀轴,由原来直径为Φ19的实心轴,变为尺寸20 mm×8 mm×6mm(外径×内径×壁厚)的空心轴,耗材减少了7％,最大等效应力为55.808 MPa,减小了8.3％,且小于旋耕机刀轴的最大等效应力56.818 MPa.改进后刀轴最大变形0.0202mm,小于原设计的0.020 6 mm,也小于基准刀轴的0.029 34一.结果表明若新设计零件与基准产品具有相同的应力和应变,则两者的强度可靠性相同.改进后的微耕机刀轴,具有更合理的受力、结构和尺寸.