Abstract:For the traditional no-tillage planter, the straw and stubble could be cut or removed in the operation, so there was still high quality of performance requirements for cutting components, large power consumption, dust pollution and twining of straw and other issues. A kind of hill-mechanisms of no-tillage seeding was studied, which could penetrate the obstacles and then the hole was formed without any special treatment to the covering of surface. The key mechanism consisted of a duckbill type of roller seeding device and a passive roller driven by its own duckbill, both of which were in internal tangential relationship. The straw was rolled into a thin layer by the rotating drum, and then the duckbill reached and passed through the thin layer of straw to form a hole and accomplish seeding. Based on the kinematics analysis, the mathematical model among the drive angle (φ) of the duckbill, the power angle (α) of the duckbill, the angular velocity (ω0) of duckbill type of roller seeding device and the angular velocity (ω1) of the drum was established. According to the seeding condition that the spacing must be integral multiple of 100mm, the Matlab (matrix laboratory) image processing module was used to analyze the equation of the models, and the structure and work requirements were chosen as the constraints, the speed fluctuation of rotating drum was selected as the main measure index and the compact condition of structure as the auxiliary measure index, thus optimized to obtain the optimal combination of the parameters: the radius of the duckbill wheel seeding device was 200mm, the radius of the rotating roller was 400mm, the power angle of the duckbill (α) was 23°, and the initial driving angle (φ) was 31°, then the number of driving holes of the rotating drum was calculated as 23, the size of which was 84mm×32mm by the method of further geometric analysis. Using CATIA to do digital prototype motion simulation, the practical situation and the change rule of angular velocity when the rotating drum under the action of the duckbill were analyzed, therefore the theoretical analysis was verified. The prototype test showed that the passive roller type of no-till planter hill-mechanism could meet the design requirements, it was simple and reliable in working process and it was also an effective technical choice for no-tillage seeding.
