下部烟叶机械采收的最佳施力方式试验

Experiment on Harvesting Force for Mechanical Harvesting of Lower Tobacco Leaves

为了明确烟叶机械采收的损伤机理,降低烟叶破损率,以中烟100为试验材料,在万能试验机上利用自制夹具对成熟和未熟烟叶进行了采收力作用方向和作用位置的施力方式试验,并分析了烟叶成熟度、施力方式对茎叶断裂损伤的影响。结果表明：成熟烟叶茎叶分离所需要的力和断面面积呈线性关系;成熟烟叶和未熟烟叶茎叶连接界面属于各向异性界面连接,未熟烟叶各向异性界面连接更为明显;成熟烟叶比未熟烟叶界面结合强度小,强度下降约29%,属于弱界面连接,此时机械采收易于降低烟叶破损程度;最佳的施力方向为斜向施力;力的作用点位置在距离茎叶结合处50~60 mm以内时,便于烟叶从茎叶连接处断裂。

In order to investigate the causes of tobacco leaf damage in mechanical harvesting and reduce leaf breakage, an experiment on Zhongyanl00 was carried out with a universal testing machine and self-made clamps. The acting direction and acting position of harvesting force on immature and mature tobacco leaves were tested, and their relations to the crack and damage of stalk and leaf were analyzed. The results showed that for mature leaves, there was a linear relationship between the cross-sectional area and the harvesting force needed. The stalk-leaf joint was an anisotropic connection, which was more obvious in the instance of immature tobacco leaves. The connection strength between stalk and mature leaf was lower than that between stalk and immature leaf by about 29%, the joint was relatively weaker, and it was the right time for mechanical harvesting to reduce leaf breakage. Exerting an inclined force on leaf within a distance of 50 to 60 mm from the joint would be preferable to break the leaf off the stalk.