Design And Experiment Of Threshing And Cleaning Device For Rice-oil Combine Harvester In Hilly Mountain Area

The hilly and mountainous areas of southern China are mostly located in the middle and lower reaches of the Yangtze River,and these areas are mostly rice-oil,ricerice-oil rotation crop production modes.Although the research of rice combine harvesters in China started early,developed rapidly,and the technology of large and medium-sized combine harvesters is relatively mature,but in hilly and mountainous areas,due to the small and scattered fields,the narrow arable roads,and the large gradient of the ground,the field operations of the machines,Transfer and transportation are more difficult than the plain,large and medium-sized combine harvester can not adapt to the harvest of rice oil in hilly mountains,so the mechanization level of rice and rape in hilly mountains is relatively low.Improving the level of agricultural mechanization of the main crops in the hilly and mountainous areas of the South can improve the productivity of farmers and is of great significance for agricultural modernization.The threshing separation device and cleaning device are the most important working parts of the combine harvester,and it is necessary to design and test it.In order to provide a design basis for the threshing and cleaning device of rice-oil combined harvester in hilly and mountainous areas,this paper firstly studies the agronomic characteristics and material characteristics of rice and rape in hilly and mountainous areas,combining the research of domestic and foreign scholars and the characteristics of rice oil in hilly and mountainous areas And the problems existing during harvesting,a threshing and separating device for rice oil in hilly and mountainous areas was designed,and then the characteristics of the threshing mixture were analyzed and studied using the designed and threshing and separating device..Finally,through the field orthogonal experiment of rice and rape,according to the collected and analyzed experimental data,the working parameter combination suitable for rice and rape in hilly and mountainous areas was obtained.The specific research content of this article includes the following aspects:(1)The agronomic traits and material characteristics of early rice in the mountainous area of Taizhou,Zhejiang Province and japonica rice in Zhenjiang area were studied.The morphological parameters,moisture content,and grain connectivity of the rice were determined.The study found that the early rice grain connection in the hilly mountain area is smaller than that of japonica rice,and the grain falling is relatively easy,which provides a basis for the design of the subsequent threshing and cleaning device.The agronomic traits and material characteristics of rapeseed in Zhejiang area were studied.From the determination of the main stem diameter,plant height,height of the first branch off the ground,the thickness and diameter of rapeseed,the rape branch was found There are many,stalks are thick and tough,and the consistency of rape maturity is poor.In view of these problems,a suitable threshing and cleaning device is designed.(2)Design of threshing and separating device of rice-oil combine harvester in hilly and mountainous areas.The types and working principles of threshing and separating devices are briefly described,and the overall structure of the threshing and separating device of rice-oil combined harvester in hilly and mountainous areas of this subject is introduced,including adjustable diversion bar angle cap,single longitudinal axial threshing and separating Drum and grid type concave plate screen,and give the relevant parameters and working principles of these parts.Aiming at the problems of different rice-oil and rice-rice-oil production modes,early rice is easy to thresh,large threshing damage and poor consistency of rape maturity,a new threshing separation device is designed to improve the harvest efficiency of rice and rape in hilly and mountainous areas.(3)Design of threshing and separating device of rice-oil combine harvester in hilly and mountainous areas.The overall structure of the threshing and separating device of rice-oil combine harvester in hilly and mountainous areas,as well as the positional relationship and assembly relationship between the parts,are mainly introduced.The format concave plate sieve and other components are introduced.At the same time,the designed open longitudinal axial flow threshing separation drum is introduced,which mainly uses threshing elements to thresh and rub the rice and rape materials.In view of the problems that the length and diameter of the traditional closed axial flow drum are large,which leads to high power consumption,and the large mass is not suitable for use in hilly and mountainous areas,the length,diameter,threshing element,threshing gap,top cover,etc.The size and structure are designed to meet the requirements of thorough threshing and separation,smooth material transportation,and low power consumption,thus adapting to the harvest of rice and rape in hilly and mountainous areas.(4)Verification of rice and rape field trials.Field trials of rice and rape were conducted on the threshing and cleaning device of rice-oil combined harvester in hilly and mountainous areas.Taking the loss rate and impurity rate of threshing and sorting as the test performance evaluation indicators,the four influencing factors of the top cover guide bar angle,the form of threshing element,the speed of the threshing drum and the opening of the scale of the vibrating screen are the research objects Carry out multi-factor orthogonal test,obtain the test data in the field by manual collection and determination,the test data conforms to the national standard.By analyzing the test data through the method of range analysis and analysis of variance,it is concluded that the impact of various factors on the loss rate during rice harvesting is: drum rotation speed> fish screen opening> diversion bar angle> threshing element form.The effect of the rate is: threshing element form> drum speed> fish scale screen opening> guide bar angle;the impact of various factors on the loss rate when harvesting rape is: drum speed> fish scale screen opening> guide bar angle> threshing Element form,the influence of various factors on the impurity rate is: diversion bar angle> threshing element form> drum speed> fish scale screen opening.The comprehensive impact of various factors on the test performance index is analyzed,and the optimal working parameter combination is finally obtained: the angle of the top cover guide bar is 72 °,and the threshing element is selected to be able to ensure the loss rate and impurity rate of the rod-nail roller,roller The rotating speed is 700 r / min,and the opening of the fish scale is 25 mm.