DESIGN AND EXPERIMENT OF FINGER-CHAIN GRAIN LIFTER FOR RATOON RICE STUBBLE ROLLED BY MECHANICAL HARVESTING

Abstract

For rice ratooning, the lateral bud germination of the rice stubble after the first harvesting can be used to continue the next growing season, but the first harvesting machinery will crush and damage the rice stubble, resulting in the reduction of yield in the ratooning season. Lifting the rolled stubble can reduce this loss, and thus a double-chain finger grain lifter was designed in this study. Then, a kinematic model and motion trajectory curve of the grain lifter was established. The influence law of the chain speed, chain spacing and the number of fingers of the rear lifting chain was determined. Furthermore, taking into account the success rate and the rate of secondary damage of the lifting, a full-factor bench test was performed. The best operating characteristics of the grain lifter are: chain speed of 345 r/min, adjacent chain spacing of 300 mm, and the number of gears and fingers on the rear lifting chain of 3. The success rate and the secondary damage rate of the lifting is 90.05% and 1.72%, respectively. A field verification test was conducted, with an average success rate of 55%. The results of this study can provide valuable reference for the lifting technology of rolled rice stubble and promote the whole mechanized production of ratoon rice.