烟秆拔秆机刀辊参数优化与试验

Parameter Optimization and Experiment on Knife Roller of Tobacco Stalk Pulling Machine

针对烟秆拔秆机存在拔秆作业能耗高、工作不稳定、刀辊受力不均等不足,对其核心工作部件刀辊的结构参数和工作参数进行优化与试验研究。首先,对刀辊旋耕刀切土轨迹、沟底不平度、切土节距、拔秆入土深度和旋耕速比进行了理论分析,并结合刀辊拔秆工作原理和拔秆农艺要求,确定了拔秆机刀辊较优参数设计组合为:拔秆机前进速度v_m=0.3 7 m/s,切土节距S=1 0 0 mm,旋耕速比λ=8,刀辊转速n=1 1 0 r/min。其次,对影响刀辊工作质量和功率消耗较大的旋耕刀参数及排列进行了研究,包括旋耕刀侧切刃、正切刃、正切部弯折半径、工作幅宽及刀辊回转半径等,得到适合于反转拔秆的旋耕刀参数为:螺线起点的极径ρ_0=1 6 3 mm,螺线终点的极径ρ_n=2 4 0 mm,螺线终点的极角θ_n=3 1.8°,弯折半径r=3 0 mm,旋耕刀幅宽b=3 0 mm,并提出了旋耕刀在刀辊上的4n±2最优数列双螺旋线排列法。田间作业试验表明:刀辊拔秆作业质量较好,性能稳定,设计合理。

Aiming at the problem of high energy consumption,instable operation and non-uniform stress of knife roller,the structure parameters and working parameters of the knife roller which is a core component of the tobacco stalk pulling machine are optimized and experimental study. Firstly,based on the theoretical analysis on the soil cutting trajectory of rotary blade which is installed on the knife roller,hardpan roughness,cutting pitch,cutting depth,rotary cultivation speed ratio as well as the operating principle of stalk pulling of knife roller and agronomic requirements of stalk pulling,the following combination of better parameters of stalk pulling machine knife roller was determined： forward speed for vm= 0. 37 m/s,bite length for S = 100 mm,rotary cultivation speed ratio for λ = 8,revolving speed of knife roller for n =110 r/min. Secondly,after studying the parameters and arrangement of rotary blade with great impacts on the operation quality and power consumption of knife roller,including side cutting edge,sidelong edge,bending radius of tangential part,working width and turning radius of knife roller etc.,we obtained the following parameters of rotary blade suitable for reverse stalk pulling： the polar radius of spiral starting point for ρ0= 163 mm,polar radius of spiral end point for ρn=240 mm,polar angle of spiral end point for θn= 31. 8°,bending radius for r = 30 mm,breadth of rotary blade for b =30 mm. And the 4 n ± 2 optimal sequences double helical line ranking method for rotary blade on the knife rollrer was put forward. The field experiment showed that high stalk pulling quality,stable performance and reasonable design of knife roller.