Experiment Study And Application Of Cyclone Separating Davice Based On Off-centered Inlet Scoop

The cleaning device is an important operating part on grain combine harvester, and has a direct impact on the machine working performance such as cleaning rate, loss rate and work efficiency. As a airflow cleaning mechanism, cyclone separating system occupies large part in small-scale crop harvesters, for its remarkable advantage of simplicity and light weight. But such defects of this common mechanism in market like the fan’s high rotation speed over2600r/min, and heavy vibration are badly impairing the working performance and reducing its working stability. It is effective to reduce the fan speed through diminishing diameter of cyclone separating tube but inevitably leads to drop of cleaning quality.To improve the cleaning quality of cyclone separating device, off-centered inlet scoop as a imagine was put forward. That is the center of inlet scoop was offsetted a certain distance relative to the center of cyclone separating tube based on stay away from the feed inlet direction. Through the test, to explore the cleaning performance of cyclone separating davice based on off-centered inlet scoop,and the influence of the off-centered inlet scoop’s rotation angle in conjunction with the inlet scoop offset distance on the performance of cyclone separating device was studied, The experimental results showed that, cyclone separating device based on off-centered inlet scoop can reduce cleaning loss rate, and reduce the fan speed effectivly. Put the rice as cleaning materials, when the rotation angle of off-centered inlet scoop δ=150°, the offset distance of inlet scoop is d=35mm, cleaning effect was as well favorable, and the cleaning rate Yq≥99%and the loss rate Ys≤0.1%; put the wheat as cleaning materials, when the rotation angle of off-centered inlet scoop δ=30°, the offset distance of inlet scoop is d=35mm, cleaning effect was as well favorable, and the cleaning rate Yq≥98%and the loss rate Ys≤1%.In order to fully grasp the performance law of cyclone separating davice based on off-centered inlet scoop, to get the optimal parameter combination. Orthogonal experiment and regression test was carried out, put rotation speed of fan, rotation speed of winnower, diameter of the inlet scoop, and diameter of the grain export as test factors, the grain cleaning rate and cleaning loss rate are selected as the indicatorst.Through the rice cleaning test, the optimal parameter combination arrived as following:when rotation speed of fan Nf=1157r/min, rotation speed of winnower Ny=1065r/min, diameter of the inlet scoopΦ2=155mm, the cleaning rate is Yq=99%, and the loss rate is Ys=0.06%. Through the wheat cleaning test, the optimal parameter combination arrived as following:when rotation speed of fan Nf=1348r/min, rotation speed of winnower Ny=1012r/min, diameter of the inlet scoopΦ2=147mm, the cleaning rate is Yq=98%, and the loss rate is Ys=0.86%. The test provide evidence for cyclone separating device based on off-centered inlet scoop was collocated on micro-combine harvester of grain.