Abstract:Aiming at the problems of large seed amount, large variation coefficient of sowing amount and uneven sowing, a spoon-tongue precise point planter for flax was designed based on the physical characteristics of flax seeds and the requirements of planting agronomy. By analyzing the working principle of the burrow planter, the composition of the burrow planter, the range of structural parameters and the number of installations were determined. The mechanical analysis of the process of spooning seed and clearing seed was carried out to determine the rotational speed range of the burrow planter. According to the EDEM simulation process, the pattern inner wall chute can not only improve the simulation efficiency, but also increase the seed fluidity, which was convenient for the scoop filling. With the rotation speed of the burrow planter, the radius of the transition angle at the top of the scoop and the height of the isolation plate of the seed chamber as the test factors, and the qualification rate of seed exclusion, the leakage rate and the replay rate of the burrow planter as the test indicators, the quadratic rotation orthogonal combination test was carried out by using EDEM discrete element simulation software. The results showed that the optimal parameter combination was as follows: the rotating speed of the burrow planter was 2.9rad/s, the tip of the scoop was 2.5mm, and the height of the isolation plate was 6.8mm. The seed discharge performance of the spoon was verified by 3D printing. The average pass rate, miss rate and repeat rate of the spoon were 87.00%, 6.33% and 6.67%, respectively. Field experiments showed that the qualified rate of the spooning spoon was 88.33%, the missed rate was 6.67%, and the replay rate was 5.00%. The average planting density of flax was 50 plants/m2, the results of bench test and field test were basically consistent, and the performance met the agronomic requirements of fine sowing flax.