Abstract:Considering the problems that the soil surface is uneven, large area, and broad width in the process of the sowing operation, which leads to the poor uniformity and stability of sowing depth in each line of the planter, a prototype of profiling chisel sowing opener was developed based on elastic deformation of profiling roller. The working principle of the profiling chisel sowing opener was elaborated. The curvilinear equation of the chisel blade edge was determined, the mechanical model of interaction between opener and soil was established, and the relationship between the elastic deformation of the profiling mechanism, the profiling resistance and the profiling quantity was clarified. The influence of chisel surface blade edge width, profiling roller diameter, entrance angle, and sowing depth on the sowing depth stability was tested with quaternary primary regression orthogonal combination test method and high speed digital soil slot platform. The experiment results indicated that when the blade edge width was 12mm, the profiling roller diameter was 24mm, and the entrance angle was 22°, the sowing depth stability was better. The field comparative experiment results showed that under the optimum combination of parameters the depth variation coefficient of the profiling chisel opener was less than 9%, the surface smoothness was lower than 18.5mm, and the profiling chisel opener had non-tangled grass, piled-up earth. The ditching performance of the profiling chisel opener was superior to that of wing spade opener. The field seeding emergence test results indicated that as the rapeseed and wheat planting by the broad width precision no-tillage planter for rapeseed and wheat with 4.8m working breadth and sowing 24 rows, the variation coefficient of single row seedling number and variation coefficient of each row seedling number were both less than 10%, the average seedlings number of each row of the wheat, the spring rapeseed, and the winter spring was 35, 26 and 20 within a meter, respectively. The seedlings number of each row of the wheat and rapeseed could satisfy the requirement of precision seeding and seedling rate, which can provide reference for the design of planting ditch opener for rapeseed and wheat.
