DESIGN AND EXPERIMENT OF KEY COMPONENTS OF PADDY FIELD WEEDING DEVICE

ABSTRACT A type of weeding device was designed to solve the problems of weeders in paddy fields, such as high rice seedling damage and low weeding rate. The structure of the weeding machine and the working principle are illustrated. The seedling avoiding and weeding mechanism of the weeding device were analyzed. The parts of the weeder that contacted the soil were designed. The contact process between the spring tine and soil in paddy was simulated using the discrete element method to study the change in mechanical behavior during the working process. To verify the performance of the weeding machine, the forward speed and hoeing depth were taken as experimental factors, and weeding rate and rice seedling damage rate were selected as test indices. Field experiments were conducted to study the effects of each factor on weeding operations. The results of the experiment were evaluated by multi-index comprehensive weighting. The test results showed that, when the forward speed was 0.30 m/s and hoeing depth was 40 mm, rice seedling damage rate was 3.4%, weeding rate was 85%. The weeding machine satisfies the requirements of weeding in paddy. This research can provide a reference for the design of intra-row weeding devices in paddy.