Design And Experiment Of Single-row Type Weeding Machine Applied To Film Mulching And Transplanting For Paddy Field

In recent years,as the organic rice planting area increased every year,a new type of planting pattern has emerged on the basis of common transplanting rice seedlings,which called Paddy rice transplanting technology.The technology is an innovative technique for rice cultivation,It is characterized by spreading a degradable plastic film(paper film,biomass film,etc.)on the surface of a paddy field,puncturing the film and inserting seedlings.Compared with the traditional organic rice planting,rice transplanting cultivation techniques reduce water evaporation and inhibit the weed growth,increase soil fertility,improve work efficiency.Through the mulching of the plastic film,the paddy field can create an environment which conducive to the growth of rice seedlings and suppress the growth of weeds in the early stage.In the process of organic rice planting,most of the field weeds cannot germinate because of the plastic film mulching,however,the weeds between the rows of rice plants were not covered with plastic film,which seriously reduced the quality and yield of organic rice.Traditional manual weeding also has the disadvantages of large labor intensity,low operating efficiency,and high cost,which is not suitable for organic rice weeding operations.The application of mechanical weeding has become an inevitable trend.In recent years,mechanical weeding has become a key measure for the production of organic rice.At present,the weeding machines are mainly designed for the requirements of equal spacing agronomical requirements,and the weeding components are mostly in the form of active or follow-up caries,the structure is single and the weeding efficiency is relatively low.In order to solve the problem of difficulty in weeding between paddy film and paddy fields and improve the efficiency of weed machine,we designed a single line weeding machine between membranes by means of theoretical analysis,computer software technology and experiments.Tested to verify its performance.The main contents of the study are as follows:(1)In order to meet the agronomic requirements for weeding between the membranes,we determined the form of the weed cutter as a portable single row weed cutter for the basic conditions of the plots planted with transplanted rice.Combining different methods of weeding,the weeding component was determined to be a compound structure of a weed cutter head and a walking wheel,and the weeding principle of the weeding component was analyzed.A theoretical analysis was made on the width of the weed cutter head,the number of teeth of the weed cutter head,and the bending angle of the weed cutter head.The three-dimensional modeling software Pro/E was used to model the weeding parts and the finite element analysis software was used.ANSYS performed finite element analysis on the weeding cutter head and the weeding wheel respectively,which provided a theoretical basis for the design of the single row weed cutter machine.(2)The structure of the whole machine is designed,and the mechanical transmission plan of the whole machine is determined.Using techniques of parametric design,the three-dimensional modeling of the whole machine is performed using Pro/E software based on feature modeling.The single-cylinder double-stroke air-cooled mixed oil engine with the maximum output power of 2.2 kW was selected.The main gearbox used the worm gear reducer with the transmission ratio of 1:30,The compact structure and reasonable layout make it suitable for inter-membrane weeding operations.(3)The kinematics of the key components of the whole machine was studied,the kinematics model of the key components was established,the kinematics simulation software ADAMS was used to carry out the motion simulation analysis of the key components;and the statics of the weeders under static operation was studied to establish the weeding components,racks and The mechanical equations of the three key parts of the float were simulated,and then the mechanical model of the whole machine was established.The maximum theoretical driving torque required for the complete machine was derived.(4)Field weeding tests were conducted.The weeding rate was selected as the test index.The speed of the machine and the depth of weeding were used as single factors and multi-factor tests in the field.Data processing software Design-expert8.0.6 was used to process the analytical test data,and the influence order of various factors on the herbicide rate was determined.Field experiments show that the single row weeding machine has reasonable structure,stable performance,light weight and low consumption,and good weed control effect.,and the weeding rate is above 75%.When the machine advance speed is 0.37 m/s and the weeding depth is 101 mm,the weed rate reaches the maximum and the weed rate is 79.97%.It is necessary to meet the agronomic requirements for weeding in planted paddy fields.