油菜钵苗钵体的力学特性

针对油菜钵苗移栽过程中钵体受损影响钵苗成活率的问题，研究油菜钵苗钵体在顶苗夹具作用下的运动及力学特性，探究在不同含水率下钵体顶出力、脱离位移和承压力之间的变化规律，为油菜移栽机顶苗取苗机构参数设计提供依据。结果表明:钵体顶出力随钵体含水率的提高而增大；当钵体含水率由20.44%提高至31.02%时，脱离位移的范围由3.04~4.23 mm增长至5.02~5.44 mm，钵体承压力由5.61 N增长至7.90 N；当钵体含水率由31.02%提高至40.84%时，脱离位移的范围基本不变，钵体承压力由7.90 N减少至4.83 N。即钵体承压力随含水率的提高先增大后减少，呈非线性变化，且在相同含水率下，钵体的承压力基本不变；综合得出钵体含水率在30%左右时，有利于油菜钵苗被顶出，且钵体受损较小。 

Mechanical Properties of Rape Seedling Pot

In view of problems of survival rate of rape pot seedling was affected by damage of seedling pot in the process of transplanting rape pot seedling，movement and mechanical properties of rape seedling pot under action of push-out seedling fixture were studied，change rules of ejecting force，motion displacement and pressure under different moisture content were explored，which could provide basis for parameters design of push-out seedling device and picking seedling mechanism of rape transplanter.Results showed that ejecting force of seedling pot was increased with raising of moisture content；as moisture content of seedling pot raised from 20.44% to 31.02%，range of motion displacement changed from 3.04～4.23 mm to 5.02～5.44 mm，pressure of seedling pot increased from 5.61 N to 7.90 N；as moisture content of seedling pot raised from 31.02% to 40.84%，range of motion displacement was almost invariant，pressure of seedling pot declined from 7.90 N to 4.83 N，with the raising of moisture content，pressure of seedling pot increased firstly and then decreased，the change was nonlinear，and pressure of seedling pot changed slightly under the same moisture content；in conclusion，when moisture content of seedling pot was about 30%，rape pot seedling was ejected easy and seedling pot was damaged less.