Research Of Self-propelled Dwarf And Close Planting Jujube Harvester Pickup Device

With Xinjiang agricultural industry structure adjustment and fruit industry strategic economic policy support, jujube industry has become the Xinjiang characteristic fruit industry and one of the agriculture pillar industries, having significant economic and ecological value. As of 2014, Xinjiang jujube planting area has reached 7.25 million acres. Jujube need to pick up due to the biological characteristics of easy to drop in the harvest period. But the jujube pickup mainly rely on human beings now, existing labor-intensive, low efficiency, high harvesting costs and other problems, becoming an important factor restricting the development of the jujube industry. Domestic and foreign existing pneumatic type and mechanical type fruit picking up mechanical have injury, Omissions and other issues, cannot meet the requirements of jujube pickup job. The dwarfing close planting jujube harvester has been developed currently, but it lacks of pickup device caused the jujube can’t be achieved from land, impacting the working performance of harvester directly. Therefore, it is urgent to research a pickup device that matching with the jujube harvester, to improve the productivity of the harvester and promote the healthy and rapid development of jujube harvester.The standard dwarf close planting jujube orchard soil basic physical parameters, surface flatness distribution, jujube lowest branch height distribution law and jujube falls distribution range was obtained, by measuring the harvester working environment, based on the research of Xinjiang jujube dwarf close planting mode, the application of crank-rocker mechanism in the material throwing, analyzed the research status of the pickup machine in domestic and foreign and field research. The single grain weight, three axis geometric size, water content and other basic parameters was gained by measuring the basic physical parameters,. The limit speed of the jujube damage was obtained through jujube mechanical damage characteristics experiment.The technical requirements of dwarf close jujube harvester pickup device were proposed, and the overall structure of the pickup device was determined based on the measurement of jujube harvester working environment and material experiment. Pickup mechanism kinematics characteristics were studied and the structural parameters of the key parts were determined. The mathematical relationship among the linear velocity of eccentric, traveling speedλ, and the rotation speed of pickup lever and transport lever was obtained by studying the kinematics characteristics of jujube and pickup lever in the pickup process. The motion of the pickup mechanism was analyzed using ADAMS simulation software, and the change rule of trajectory and speed of picking up lever were studied.Regression models about picking rate, damage rate, and the pickup lever rotation speed, transportation lever rotation speed, traveling speed were established and test its reliability, using Central Composite experiment design method. For multiple regressions equation was carried out significant analysis, and the impact rules of various factors on the response indicators were researched. At last, the optimal working parameters of the pickup device was determined: pick up rotation speed lever 133.10 r / min, transportation rotation speed lever 161.43 r / min, the traveling speed of 0.24 m / s, picking up a net rate of 97.24%, damage rate 6.10%.