Improved Design Of Row-Follow No-till Wheat Planter

A new-concept of no-till wheat planter, named 2BMD-12 no-till row-follow wheat planter, had been developed by China Agricultural University to solve an extremely important problem which is zero tillage planting of wheat in narrow row spacing (150-200mm) between rows of very high-levels full length, standing maize stubble in one pass in the double cropping situation of North China. A powered rotary strip-chopping unit was placed forward of each single row of planter tines to ensure that the above-ground section of the planter tine is kept free from residue blockage. Field performance test of the machine demonstrated that it could be a good choice to work effectively for much of the time under more difficult residue conditions than that most other planters could tolerate especially when it follows well between the standing maize stubble rows.But there are still some problems existing for the rotary strip-chopping unit, planting unit and ground wheels etc. The thesis focused on improving the design of the machine to solve these problems.The strip-chopping axis was redesigned to reduce vibration and power consumption by adjusting the arrangement of the knives and on the basis of analyzing the forces on the axis. The improved machine can adapt to maize row spacing from 550mm to 700mm.More improvements were done on the planning unit focusing on the blockage and depth control issues. A new anti-blockage mechanism, which combines the powered chopping and disc opener, was designed and tested. Fertilizer was applied using the narrow tine opener with chopping unit in front of each tine; while a double disc opener, which is proved to have high residue handling capacity, was installed right behind each tine to seed into the fertilizer furrow. This new design reduced the blockage between planting units. Meanwhile seeding depth of each row can be controlled separately by the ground feeling mechanism on each double-disc opener.On the basis of force analysis of the whole machine, the ground wheels were moved to the front of the chopping unit. And some improvements or optimization on other structures of the machine were done as well.Field test showed that the machine works well for planting wheat into standing maize stubble with reduced variations for seed and fertilizer depth and improved residue handling capacity. This machine can be a good solution to no-till wheat planting in double cropping areas.