斜插式蔬菜嫁接机砧木夹持机构研制与试验

针对传统嫁接机采用整体式夹持片作为砧木夹持机构无法矫正砧木苗弯曲度而造成砧木苗夹持损伤，夹持力无法调节的缺点，该文以葫芦苗作为试验对象，在分析了葫芦苗结构参数和力学特性的基础上，设计开发了一种应用于斜插式蔬菜嫁接机并通过凸形和凹形夹持片交叉夹紧、夹持机构厚度和夹持力大小可调的砧木夹持机构，并确定了该机构的主要结构参数。试验结果表明，与普通夹持机构相比，该机构对砧木苗具有较好的导向作用，能较好地矫正砧木苗的弯曲状态，夹持成功率达到100%，提高了13.3个百分点，伤苗率仅为1.67%，比普通夹持机构减小了11.63个百分点，所设计的嫁接机砧木苗夹持机构是可行的。该研究可为蔬菜砧木苗嫁接机的设计提供参考。

Design and test of stock clamping mechanism for vegetable grafting

Abstract: Traditional stock clamping mechanisms usually install the integral clamping pieces which will injure the stock seeding because of the curvature of itself and also the clamping force can not be adjusted as needed. According to the weakness of vulnerability of stock seedling and un-adjustability of clamping force on a clamping mechanism of a traditional vegetable grafting machine, based on the analysis of the structure parameters and compression characteristics of cucurbit stock seedlings, a new clamping mechanism which was used in inclined-inserted vegetable grafting machine has been developed with convex and concave pieces cross-clamped. The thickness of the clamping mechanism can be adjusted by increasing or decreasing the number of clamping pieces, the clamping force of clamping mechanism also can be easily changed by adjusting the tension of spring which was installed on the clamping mechanism. Its main structure parameters such as the angle of clamping pieces were determined by establishing the mechanical model and analyzing the holding force of stock seedling on clamping pieces, the thickness of clamping pieces were determined by measuring the structure parameters of the stock seeding and the clamping force was determined by measuring the mechanical parameters of stock seeding. The angle of clamping pieces was designed to be 102°, the fillet diameter of clamping pieces is 3 mm and the thickness of each holding piece is designed to be 1 mm. The total thickness of the clamping mechanism can be adjusted by changing the number of the holding piece. Each side of stock clamping mechanism has 8 pieces of holding piece and the total thickness of the clamping mechanism is 16 mm. The clamping force was controlled in less than yield point pressure of 1.26 N. Experiments showed that the design of the V-shaped structure of the stock clamping mechanism had a good function in guiding the stock seeding which reduced the growing requirements of the stock seedlings. The success rate of the clamping mechanism which was new designed reached 100%, which increased 13.3% over that of an ordinary clamping mechanism. The injury rate of the new clamping mechanism was only 1.67%, which decreased 11.63% compared with ordinary clamping mechanism. Thus, it indicates that the new stock seedling clamping mechanism was feasible. It is convenient and fast for manual feeding due to the guidance of the clamping mechanism which was cross-clamped with convex and concave clamping pieces and it provides a reference for further research to improve the quality and optimize the parameter of clamping mechanism for the stock seeding of a vegetable grafting machine. At the same time, there was a space reserved for the automatically feeding of stock seeding which can be docked with an automatic seedlings mechanism.