Design and Experiment of Comb-Type Header for Plot Breeding Wheat Harvester Based on EDEM

This paper designed a comb-type header for plot wheat harvester. Based on the loss suppression mechanism during wheat harvesting, the key components of the comb-type header were designed. For the the problem of some wheat ears being unable to be combed during harvesting process, multi-stage comb tooth was designed. For the problem of seed to retention on the screw conveyor, the telescopic tooth at the feeding port of the screw conveyor was replaced with a scraper type . In order to clarify the optimal combing time, the analysis of wheat plant posture change under the action of the straw pressing nose (hereinafter referred to as nose) was carried out by theoretical analysis, simulation and bench test, and it is determined that the optimal combing moment is the stage when the plants began to rebound to the maximum reverse bending. On this basis, a numerical simulation model of the header combing system was constructed using the discrete element method, and the header loss rate as the evaluation index to explore the influence of the height of the nose, the forward speed of the machine and the rotation speed of the combing drum on the working performance. A regression model of header loss was constructed by the Box-Behnken analysis method, and the optimal working parameters of the header were determined as follows: the height of the nose was 554 mm, the forward speed was 0.65 m·s-1, the rotation speed of the combing drum was 667 r·min-1, and the loss rate was 8.59%.